Browsing by Subject "Biodiversität"

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Agricultural diversification of biogas crop cultivation
(2018) von Cossel, Moritz; Lewandowski, Iris
For all types of agricultural land-use, more diverse cropping systems are required, with respect to the maintenance of ecosystem values such as biodiversity conservation and climate change adaptation. This need for greater agricultural diversity is clearly illustrated by biogas crop cultivation. In Germany, maize currently dominates biogas crop cultivation due to its outstanding methane yield performance. However, the ecosystem value of maize cultivation decreases if good agricultural practices are ignored. Additionally, the poor aesthetical value of maize has led to biogas production gaining a negative reputation in society. To increase the diversity of biogas crop cultivation, alternative biogas crops such as amaranth and wild plant mixtures need to be investigated with respect to both yield performance and biogas substrate quality. The research objective of this study was the development of strategies for agricultural diversification of biogas crop cultivation. For this purpose, the following research questions were formulated: 1. How does amaranth perform as a biogas crop compared to maize and what are the major opportunities for and obstacles to the large-scale implementation of amaranth cultivation? 2. How does the spatial diversification ‘legume intercropping’ perform in amaranth compared to maize and what are the major opportunities for and obstacles to its practical implementation? 3. How do perennial wild plant mixtures perform in biomass production with respect to yield, quality and species diversity in the long term and what are the relevant agronomic factors? 4. How do available models perform in the prediction of specific methane yield of different crops based on their lignocellulosic biomass composition and how could they be improved? To address research questions 1 and 2, field trials with amaranth and maize were conducted in southwest Germany in the years 2014 and 2015. Amaranth established well in both years. Its dark red inflorescences attracted many insects such as honeybees, wild bees and bumble bees. Therefore, a systematic implementation of amaranth into biogas crop rotations could significantly improve their socio-ecological value in terms of biodiversity conservation and landscape beauty. However, amaranth showed significantly lower dry matter yields (DMY) and specific methane yields (SMY), together resulting in lower methane yields than maize in both years. Therefore, breeding and an optimization of agricultural practices such as sowing density, planting geometry and fertilization management are required to make amaranth more competitive in comparison to maize. To address research question 2, the amaranth field trials mentioned above also included treatments of legume intercropping with runner bean (RB, Phaseolus vulgaris L.) and white clover (WC, Trifolium repens, L.). The RB and WC developed equally well in amaranth and maize each year. For both amaranth and maize, the RB share of total DMY was low (5-10%) and did not significantly affect the total DMY. By contrast, WC had a significant negative effect on the DMY. Overall, the spatial diversification ‘legume intercropping’ could considerably improve the socio-ecological value of amaranth cultivation in terms of biodiversity conservation, greenhouse gas (GHG) mitigation and soil protection. For research question 3, two different wild plant mixtures (WPM) were cultivated on three sites in southwest Germany from the years 2011 to 2015. At each location, the WPM showed great potential for both biodiversity conservation and ecosystem resilience. Numerous insect species were observed in the WPM stands each year, indicating WPM as a relevant cropping system for habitat networking. Furthermore, the aesthetic appearance of the WPM stands over the years demonstrated the potential positive effect WPM cultivation could have on the public perception of biogas production. The DMY of the WPM varied strongly depending on (i) the initial composition of species sown, (ii) the establishment procedure, (iii) the environmental conditions, (iv) the pre-crop, and (v) the number of predominant species. WPM were found to have low demands for fertilization and crop protection. Thus, WPM appear a promising low-input cropping system for the promotion of biodiversity conservation, habitat networking, soil and water protection, GHG mitigation and climate change adaptation. However, high DMY gaps remain a challenge for the practical inclusion of WPM in existing biogas cropping systems. With respect to research question 4, a meta-analysis revealed that available models proved to be much less precise than expected. Although outperforming all available models, the correlation of the new models was still low (up to r = 0.66). It was also found that non-linear terms are of less importance than crop-specific regressors including the intercept. This indicates that across-crop models including crop-specific configurations could help to improve the identification of alternative crops and cropping systems for a more diverse biogas crop cultivation in the future.
Agrobiodiversity and its use in Naban River Watershed National Nature Reserve : implications for bio-cultural diversity conservation
(2012) Ghorbani Dahaneh, Abdolbaset; Sauerborn, Joachim
This study was conducted in the Naban River Watershed National Nature Reserve (NRWNNR), Xishuangbanna Dai Prefecture, SW China and aimed at identifying the diversity of medicinal and food plants used by local people living in NRWNNR and documenting their applications. NRWNNR is diverse biologically and culturally and people living in its territories get benefits from their diverse natural environment. However the extension of cash crops such as rubber (Hevea brasilliens (Willd. ex A. Juss.) Müll. Arg.) plantations and fragmentation of natural habitats including forests resulted in decreasing biological diversity which could be used by the local people. This also put more pressure on the remaining forests and plant resources. In order to find sustainable alternatives to conserve biodiversity and at the same time helping the development of the area it is necessary to know the available resources in the area. Among important plant resources in the area are non-timber forest products with economic and cultural importance including medicinal and food plants. Therefore, using ethnobotanical methods this study intended to document wild medicinal and food plant resources used by ethnic groups and their use details including their collection practices, preparation methods and habitat preferences. Data on useful plant resources was used to identify the main land use sources of useful plants for local people. The study also intended to understand the role of these plants in local people?s livelihood by identifying economically important medicinal and food plants traded in the area. Vulnerability of plant species to resource exploitation and harvest sustainability for selected species were assessed. To achieve above mentioned objectives, an ethnobotanical inventory of useful wild plant resources was conducted in the area to collect data on wild plant resources and uses. Semi-structured, freelisting, and household interviews were conducted from January 2008 to January 2010. Informants from Dai, Hani, Lahu and Mountain Han ethnic groups were selected randomly for freelisting and semi-structured interviews and key informants by the snowball method. Household interviews were conducted in six villages. Interviews were also conducted with harvesters and traders. All interviews were supplemented with plant sample collection for botanical identification. Plant specimens were prepared, dried, and identified with the help of local botanists. To address the vulnerability and sustainability of plant harvest, strip-transects were used to estimate the density and distribution of selected species in natural populations. Results showed that 480 plant species (25% of recorded flora) from 117 families and 334 genera are used by the local population. From these, 378 species (19%) belonging to 102 families and 277 genera are used as medicine and 161 species (8%) representing 68 families and 116 genera are used as food plants. Concerning livelihood contribution, most of these plants are used at the subsistence level and not for income generation. However some households can get from 1.1% up to 25.4% of their total annual income from sale of few medicinal species. Among food plants only bamboo shoots and mushrooms contribute to the cash income of households with the highest share in BenGang Hani village (1.1%). Knowledge of medicinal plant use and folk medicine still exists in the area and there are local healers and practitioners who are active in some villages. However this knowledge shows some differences among ethnic groups. Number of medicinal plants used by Lahu and Hani is different and some species are solely known and used by only one ethnic group. Since these ethnic groups live in neighboring villages, it was expected that a large proportion of their medicinal plant knowledge is shared. However, the diversity of medicinal species utilized by the two ethnic groups show 30% overlap. Medicinal plants are grouped into different categories based on frequency of use. 1- Frequently used medicinal plants which are few in number. 2- A large number of medicinal species are only known and collected by traditional healers or some knowledgeable elderly people. 3- A few numbers of medicinal plants are frequently and in high amounts harvested by locale people for commercial purposes and not for self consumption. Examples of these species include Asparagus subscandens F.T. Wang & S.C. Chen, Asparagus filicinus Buch.-Ham. ex D. Don, Stemona tuberosa Lour. and Paris polyphylla var. yunnanensis (Franch) Hand -Mazz. Although use of these medicinal plants is known to traditional healers, majority of the villagers which are involved in harvesting of these species are not knowledgeable about their medicinal applications. In fact harvest is driven by market demand which is brought to the area by middlemen and retailers visiting the villages. Wild food plants are also grouped based on harvest and use frequency into different categories. The first group includes species with high frequency of use which have a very common distribution range in the area. Second group includes bamboo shoots and mushrooms which are traded to some extent. The last group includes a large number of species which are not used frequently but are potential food plants used only by a small proportion of the local population or during famine or crop failure periods. Based on vulnerability assessment of marketed species in the area, most of the important plants are in danger of overexploitation. However frequently used food plants are not threatened with overharvesting since they are very common in the area. Among the wild food resources bamboo shoots and mushrooms are exploited without sustainability measures. Collection of high economically valuable medicinal plants is also not sustainable as subterranean parts are harvested and collection is fatal for the plant. Sustainable harvest and management strategies should be implemented to prevent overexploitation of these species. Findings also highlight plant species which can be proper candidates for cultivation especially in agroforestry systems. There is already a good potential on the improvement of economic gains from some forest products such as mushrooms with value adding by improving drying methods and establishment of village based enterprises. Cultivation of economically important medicinal plants in herbal gardens or agroforestry systems are recommended since it can reduce pressure on natural population and at the same time diversify and secure the economic gain of villagers.
Analysis of the impact, costs and acceptance of lapwing plots as a protection measure for farmland birds in Germany
(2023) Buschmann, Christoph; Lippert, Christian
Biodiversity in the agricultural landscape is declining in the European Union (EU) including Germany. This trend is also observed for farmland bird populations that are used as an important indicator of overall species diversity. Among farmland birds, the Northern lapwing (Vanellus vanellus) is an indicator species whose population has been particularly affected. Populations suffer inter alia from frequent cultivation measures and degraded habitat quality on agriculturally used land. To improve the status of farmland bird populations, appropriate measures are called for both in the EU and on German national level in different strategy papers. The European Commission has set the concrete target to increase farmland bird populations by 30 % until 2050. Despite the high demand to plan the implementation of biodiversity strategies, literature provides little guidance for farmland birds, i. e. ex-ante modelling of how many protection measures and how much compensation are needed to achieve certain time-bound conservation targets. The thesis addresses this research gap by analysing the impact of the conservation measure ‘lapwing plot’. Lapwing plots are fallow sections within arable fields that can be used as feeding areas and - during the breeding season - provide cover for the chicks from predators. In detail, the thesis pursues three objectives: First, to project how much lapwing plot provision is required to meet specific time-bound conservation targets on a national level by using a spatially explicit population viability analysis (PVA). Second, to calculate the corresponding costs based on implementation and opportunity costs (i. e. gross margins forgone) for compensating farmers who participate in a lapwing plot agri-environmental scheme (AES). For this, the PVA is combined with an economic analysis. Third, to analyse the acceptance of a lapwing plot AES by surveying farmers with a discrete choice experiment (DCE). PVA results show that the lapwing population in Germany could decline from 70.000 breeding pairs in 2006 to 12.000 or 23.000 pairs (depending on model assumptions) in 2055 if no further conservation measures were taken and land use remained stable. To achieve the ’30 % plus conservation target’ of the EU Commission for the lapwing, 30 % or 65 % of the breeding pairs need to be protected by a lapwing plot in arable land or a comparably effective measure in grassland. The corresponding costs for protection on arable land range from on average 1.1 to 5.6 million € per year depending on model assumptions. Costs may, however, be reduced by up to 52 % with a regionally focused economic optimisation. Since AES participation is voluntary, acceptance is of crucial importance. The DCE conducted to analyse acceptance considers different design options if the lapwing plot were introduced as an AES and identifies possible drivers and inhibitors of farmers’ participation. Remarkably, those design options which ensure that the AES can be co-financed by the European Agricultural Fund for Rural Development (EAFRD), i. e., a participation period of five years and the nature of the relevant sanctions regime, are a particular acceptance barrier. However, so far EAFRD - as part of the EU Common Agricultural Policy (CAP) - has been the most important funding instrument for AESs. Therefore, the thesis outlines how the lack of EAFRD acceptance could be addressed in the new CAP period 2023-2027 and points out alternative funding instruments. In conclusion, the lapwing plot is - according to the PVA results - a suitable measure to meet conservation objectives, such as the ’30 % plus conservation target’ of the EU Commission, if it is implemented to a sufficient extent. However, it is questionable whether a sufficient extent of implementation can be achieved if the lapwing plot is put into practice relying on voluntary AES with the available funding instruments and limited budgets. This would require a high level of acceptance among farmers in the affected regions. Therefore, the lapwing plot needs to be combined with other conservation approaches including the expansion of protected areas and in-field measures, such as the reduced use of fertilisers and pesticides. For policy makers, it is recommended to develop combined solutions in overall strategies and perform corresponding ex-ante modelling. For such strategies the thesis provides an important basis and with the PVA a suitable expandable model.
Community Structure and Activity of Nitrate-Reducing Microorganisms in Soils under Global Climate Change
(2006) Deiglmayr, Kathrin; Kandeler, Ellen
Since the beginning of the Industrial Revolution, atmospheric carbon dioxide concentrations have been steadily increasing and, thus, contributed to a warming of the climate and altered biogeochemical cycles. To study the response of soil microorganisms to altered environmental conditions under global climate change, the nitrate-reducing community was regarded as a model community in the present thesis. This functional group, which performs the first step in the denitrification pathway, was selected because it is phylogenetically very diverse. In particular rising levels of atmospheric carbon dioxide as the most important catalyst of temperature rise and the retreat of glaciers in the Alps as one of the most evident consequences of climate change were investigated. The behaviour of nitrate reducers was investigated in a biphasic approach: (i) at the level of its enzyme activity of the nitrate reductase and (ii) at the level of community structure, which was characterised by RFLP (Restriction Fragment Length Polymorphism)-fingerprints using the functional gene narG. The effect of elevated atmospheric carbon dioxide concentrations on nitrate-reducing micro-organisms was studied in the Swiss FACE (Free Air Carbon dioxide Enrichment) experiment including the rhizosphere of two functional plant types (Lolium perenne and Trifolium repens), two N fertilisation levels and two sampling dates (June and October 2002). Whereas in June no significant treatment effect was observed, the nitrate reductase activity proved to be significantly reduced under elevated atmospheric carbon dioxide at the autumn sampling date. Simultaneously, elevated enzyme activities were recorded under Trifolium repens and high N fertilisation pointing to a control of nitrate reductase activity by nitrate availability at the time of sampling. The community structure of nitrate reducers, however, showed a different response pattern with sampling date and the strongly varying pH of the different experimental plots constituting the main driving factors. With respect to the three experimental factors atmospheric carbon dioxide, plant type and N fertilisation the composition of the nitrate reducers revealed a high stability. The microbial succession of nitrate-reducing microorganisms was studied in the rhizosphere of Poa alpina across the glacier foreland of the Rotmoosferner/Oetz valley. Sampling was performed in August and at the end of the short period of vegetation in September. The nitrate reductase activity increased significantly with progressing successional age, whereas organic carbon together with nitrate concentrations in the soils explained the major part of this effect. The microbial community of nitrate reducers revealed a significant shift across the glacier foreland, with pH and organic carbon representing the most important environmental factors inducing this shift. A detailed analysis of the clone libraries that were constructed for the youngest and the oldest site in the glacier foreland pointed to the tendency of lower diversity in the late succession compared to the young succession. Possibly an increasing selective pressure due to higher densities of microorganisms and, hence, a higher competition for limited resources contributed to the decline in diversity. In conclusion, the functional group of nitrate reducers responded to changing environmental conditions under global climate change particularly through altered enzyme activities. The amount and the direction of this response depended strongly on the nitrate availability and the organic carbon content in soils. The community structure of nitrate-reducing microorganisms, however, proved to be resilient towards short-term substrate fluctuations. This indicates that the genetic pool of this group of soil microorganisms possesses a high functional stability characterized by a relatively persistent composition and an independent modulation of enzyme activity.
Conflicts of human land-use and conservation areas : the case of Asian elephants in rubber-dominated landscapes of Southeast Asia
(2017) Harich, Franziska K.; Treydte, Anna C.
Over the last decades, expanding rubber plantations in Southeast Asia have continuously diminished natural habitat, thereby increasing conflicts between human land-uses and nature conservation. The consequences are manifold, with short-term economic benefits for smallholder farmers and long-term costs for species diversity and ecosystem services (ESS). Sustainable wildlife populations are critical for ecosystem functioning but the ongoing habitat degradation and conflicts with people threaten the survival of larger mammal populations. This trend is particularly problematic if the respective species in decline are keystone species such as the Asian elephant (Elephas maximus), which holds important ecological functions in maintaining tree diversity. Continuous land-use transformations increase the importance of conservation efforts for biodiversity within the agricultural matrix. The major aim of this thesis’ work was to analyze the potential of rubber-dominated landscapes in sustaining wild mammal populations while considering the risk of conflicts due to wildlife damage as well as the ecological importance of mammals. As a first step, the literature on wild mammals in rubber and oil palm plantations was analyzed to provide an overview on species diversity found in these systems. Our review showed that species richness was highly reduced in the plantations compared to the forest and that most species in the farms were rather visitors than residents. For a detailed assessment of species richness and presence in rubber plantations, transect and camera trap surveys were conducted in the farm-forest transition zone of the Tai Rom Yen National Park in southern Thailand. Furthermore, farmers were interviewed on the kind and extent of wildlife damage. With 35 recorded wildlife species, the forest was found to hold the highest diversity while more than 70% of these mammals were still found at the forest edge. However, a strong decline of species diversity and presence was observed in the farmland. Crop damage by wildlife affected 40% of all interviewed farmers. In 85% of all rubber damage incidents, young trees were affected, which had not yet been tapped. Elephants were most frequently named as damage causing species. Nevertheless, damage to rubber occurred only in half of the elephant visits, indicating that this crop species was not particularly attractive to wildlife. To account not only for the costs inflicted through elephant damage but also for the ecological benefits elephants provide, the potential of these megaherbivores for seed dispersal was assessed as a crucial ecological function in forest ecosystems. Feeding experiments with elephants were conducted and germination success of ingested and fresh control seeds of a tree species with characteristic mega-faunal syndrome fruits (Dillenia indica L.) was monitored. Seeds ingested by elephants showed a significantly higher and earlier likelihood for germination compared to control seeds. The exemplary tree species in our experiments did not solely depend on but benefited from elephant consumption for germination. This highlights the risks of long-term negative implications for certain tree species and entire ecosystems if elephant and other large mammal populations further decline. Biodiversity is an integral component of ecosystem functioning and the provisioning of services. However, a challenge in the evaluation of ESS is the allowance for the many facets of biodiversity assessments. We therefore developed a methodology for including multiple levels of species diversity into an ESS evaluation model. Diversity data of animal groups and plants derived from our data collections and from literature were normalized using the most diverse habitat as benchmark. Through this approach we obtained a comparable habitat suitability matrix for different land-use systems, which was then applied to different land-use scenarios. The outcomes confirmed that a conservation focused scenario scored higher habitat suitability for all species as well as for threatened ones compared to two other scenarios with no or limited conservation measures. Increasing conflicts between human land-use and nature conservation as a result of shrinking resources pose imminent risks for the diversity and resilience of ecosystems. This thesis provides an assessment of the current state of and conflicts with wildlife diversity in rubber-dominated landscapes surrounding protected areas. The results of this thesis can serve as a basis for the development of measures to consolidate farming and conservation interests. Although intensively managed plantations cannot substitute for natural forests, efforts are required to conserve multiple levels of biodiversity within the farming landscape. High species diversity will maintain ecosystem functions and services sustainably, which both human and wildlife communities rely on for their long-term persistence.
Costs and benefits of ammonia and particulate matter emission abatement and interactions with greenhouse gas emissions in German agriculture
(2017) Wagner, Susanne; Zeddies, Jürgen
In the past decades, agricultural and particularly livestock production have increased with population growth and increasing demand for food, especially for livestock products, at global level. This trend is expected to continue in the coming decades and may even be fortified by an increasing demand for non-food biomass in an economy based on renewable biological resources. Agriculture influences also the state of the environment. Agriculture has been associated with expansion into natural ecosystems, adversely affecting biodiversity and has a large share in the global emissions of greenhouse gases and ammonia (NH3) and in the release and formation of primary and secondary fine particulate matter (PM2.5). NH3 emissions can lead to a loss of biodiversity in nitrogen-limited terrestrial ecosystems and can form secondary PM2.5 in the atmosphere. PM2.5 emissions may affect human health by causing respiratory and cardiovascular diseases and a reduction in life expectancy. As NH3 and PM emissions partly originate from the same production activities as greenhouse gases, interactions between NH3 and PM emission abatement and greenhouse gas emissions may exist. Emissions can be reduced by technical measures or by shifts towards a diet low in animal-based food products, because plant-based food products cause fewer emissions than animal-based food products. In Germany, agriculture contributes about 95% of the total NH3 emissions and 5% to primary PM2.5 and 8% to greenhouse gas emissions. Because of the environmental impacts and subsequent governmental regulations, there is a need to reduce emissions of NH3, PM2.5 and of greenhouse gas emissions significantly. The main objective of this thesis research was to increase the understanding of the full effects of NH3 and PM emission abatement in agriculture. Particularly, it aimed to quantify and compare farmers’ costs and society’s benefits of reducing NH3 and PM emissions in agriculture in Germany while considering interactions with greenhouse gas emissions and to identify cost-efficient NH3 and PM emission abatement measures. Both technical NH3 and PM emission abatement measures and a diet shift were examined with respect to the abatement costs and the benefits in terms of avoided damage costs of impacts on human health, terrestrial biodiversity and the climate. The analysis combined agricultural emission modelling and integrated environmental impact assessment, applying the impact-pathway approach, complemented by literature analysis. The abatement potentials ranged from 2 to 45% for NH3 emissions, from 0 to 38% for PM2.5 emissions and from 0to 49% for greenhouse gas emissions. The abatement potentials of a diet shift exceeded those of technical abatement measures. All air pollutant abatement measures affected greenhouse gases, in most cases synergistically. The average abatement costs ranged from 2.7 to 25.6 EUR per kilogramme NH3 reduced, from 7.5 to 31.2 EUR per kilogramme PM2.5 reduced and 0.01 to 0.03 EUR per kilogramme greenhouse gas emissions reduced. The average benefits were 24.5 EUR per kilogramme NH3 reduced and 68.3 EUR per kilogramme PM2.5 reduced. The benefits of reduced health damage costs were higher than those of reduced biodiversity loss, resulting in higher benefits of PM2.5 reduction. The benefits of the reduction of greenhouse gas emissions were 0.09 EUR per kilogramme. In conclusion, synergies with greenhouse gas mitigation reduced the abatement costs per unit of emission type, increased the benefits and improved the cost-efficiency of air pollutant abatement measures. This finding indicates that air pollutant abatement and greenhouse gas mitigation should be analysed together and that environmental policy design should consider interactions. The abatement potentials of technical measures were limited and should be complemented by changes in food consumption patterns to meet politically agreed emission reduction targets. Besides emission reductions, diets with low consumption of animal-based food provided land for alternative uses such as food production, lignocellulosic biomass production or biodiversity conservation that have the potential to reduce pressure on land from increasing demand for food by a globally growing population or for lignocellulosic biomass in an economy based on renewable biological resources.
Developing a biodiversity evaluation tool and scenario design methods for the Greater Mekong Subregion
(2011) Cotter, Marc; Sauerborn, Joachim
The Xishuangbanna Prefecture in Yunnan Province (PR China) is facing increasing conflicts between rural development and nature conservation because of an ongoing expansion and commercialization of farming. The rapid development of large-scale farming and the improvement of infrastructure throughout the region are posing serious threats to the conservation of endemic species of flora and fauna, while also offering possibilities for enhancing the livelihood of rural populations to an extend never seen before. The expansion of rubber (Hevea brasiliensis Willd Ex A. Juss) has caused a reduction and fragmentation of natural and secondary forest cover, thereby decreasing structural and species diversity as well as the loss of valuable ecosystem services. The establishment of intensified agriculture, especially plantations on sloping terrain, often leads to an increased erosion risk, nutrient run-off and sedimentation in water courses. Thus, large scale deforestation is not just a problem for nature conservation but also one for the rural economies. Rural development and simultaneous environment conservation often face trade-offs, especially in regions that host an exceptionally high biodiversity, such as many tropical areas. In order to adequately consider and evaluate these interactions, tools and methods have to be developed that allow decision makers to assess the impacts of different management and infrastructure options on the environment. The aim of the work presented in this thesis was to analyze and evaluate the effect of large-scale rubber cultivation on local and regional biodiversity by developing methods to integrate field studies from various disciplines into a comprehensive assessment model. This model was then used to highlight key aspects of anthropogenic influence on the plant species composition within the research area and to identify possible impacts of alternative land use decisions. Furthermore, the development of an interdisciplinary approach to scientific scenario design methods has been supplemented with a study on the acceptance of 3D-visualization as communication tool for land use planning in the background of nature conservation sciences. In order to achieve this, an overview of the agronomical and ecological aspects of rubber cultivation was provided. Literature sources referring to the impact of different cultivation systems on natural biodiversity were discussed and an introduction to the effect of rubber cultivation on Ecosystem Services was given. A method for projection of regionally adapted carbon capture properties of rubber cultivation under suboptimal growth conditions was presented and a comparative assessment of greenhouse gas emissions during the establishment of rubber plantations in regard to the preexisting vegetation was made. A biodiversity evaluation tool based on the combination of approaches from landscape ecology and empirical data within a Geographic Information System was developed. Detailed data on plant species diversity and distribution were combined with quality criteria like endemism or invasiveness to form spatially explicit biodiversity indices for different land use types in various elevation classes. Up-scaling in accordance to the land use distribution observed allowed the estimation of overall plant diversity and the evaluation of the effect of possible future land use scenarios. Habitat characteristics and spatial distribution were included into the analysis of the land use map derived from remote sensing information to allow for the assessment of fragmentation and landscape matrix structure. The methodology was tested with an array of possible present and future land use maps. It was possible not only to evaluate the different land use classes within and their distribution throughout the research area, but we were also able to compare distinct sub-regions based on topography or administrative status. The challenges stakeholders and nature conservation face in the different elevation zones of Nabanhe were highlighted and related to the findings of our partner workgroups from economy and social sciences. The feasibility of this approach to administration staff with limited experience in ecological modeling was one of the main goals in designing the methods. Given a reasonable data set on species diversity and distribution within any given tropical research area, this approach will enable planners and nature park administration to quickly project possible consequences on species diversity indices deriving from land use change within their respective research area. Using this approach, the importance of natural tropical forests for the maintenance of species diversity in tropical cultivated landscapes was highlighted. With the information gained from constructing this evaluation tool, the design and development process for a land use scenario based on the integration of multidisciplinary assessments and iterative scenario refinement with repeated stakeholder inclusion was promoted. By combining stricter conservation rules with alternative sources of income for the rural population in order to offer an alternative to monoculture rubber farming, the economic models and the land use allocation model predicted a stop in rubber and agriculture related deforestation, and the establishment of a considerable amount of reforested area. This was achieved by introducing an innovative land use type that is closely related to traditional local home garden agroforestry systems. By coupling reforestation efforts with the economic gain derived from intercropping Traditional Chinese Medicinal plants into degraded secondary forests, this scenario was, at least theoretically, able to remove deforestation pressure from the natural forest types and to offer an economic alternative to rubber cultivation. The methods used for this assignment can serve as guideline for future projects that want to implement scenario design procedures based on the combination of social sciences, economics, ecology and landscape planning. The acceptance and comprehensibility of computer based 3D visualization models for the communication of possible future land use scenarios was also tested. Two alternative scenarios were visualized and compared to the status quo, with questionnaires and guided interviews covering the acceptability and adaptability of such techniques for professionals from various fields of nature conservation. This thesis presents an overview over agronomic, economic and ecological aspects of rubber cultivation and highlights its implications on biodiversity and nature conservation. The methods discussed here can serve as a guideline for the integration of ecological indicators in land use planning and decision making processes. Although the concepts and topics introduced herein are closely interlinked within the framework of the Living Landscapes China (LILAC) research project, the methods and approaches can easily be applied to other areas in the Greater Mekong Subregion and beyond, be it the expansion of oil palm plantations in the Malayan Archipelago or the fragmentation of forests due to increased population pressure in Central Africa. Nature conservation is facing similar problems all over the developing world, and adaptable approaches such as the ones presented here are needed to support decision making processes in order to secure the preservation and long-term survival of the worlds? diversity in species and natural habitats.
Elucidating the megadiversity of Chalcidoidea (Hymenoptera) with a multi-taxonomic approach
(2022) Haas, Michael; Krogmann, Lars
With over 22,500 described and up to 500,000 estimated species, the jewel wasps (Chalcidoidea: Hymenoptera) are among the most species-rich insect lineages. Their evolutionary success is tightly linked to their parasitoid biology, having evolved to utilize a wide array of different arthropod hosts. Additionally, secondary phytophagy evolved several times within this superfamily. Although new approaches are employed in integrative taxonomic research, progress to decipher the megadiversity of this taxon, including their evolution, is still limited. With this work, the diversity of the superfamily is studied at two evolutionary key points in time. The evolutionary origin of Chalcidoidea is investigated in the Cretaceous and the resulting diversity since then is examined in the present. Different systematic levels will be elucidated with the help of integrative taxonomic methods. In the first chapter, the fossil origins of jewel wasps are addressed, around the middle of the Cretaceous period 110 million years ago. The morphology of a putative early chalcidoid specimen is studied, as it is highly informative for chalcidoid evolution due to its age. Based on those results, its phylogenetic placement is critically examined. The specimen is assumed to be one of the oldest described chalcidoid fossils, Parviformosus wohlrabeae Barling et al., 2013. It is a key fossil because of its age and putative assignment to the polyphyletic family Pteromalidae and could therefore be a valuable voucher for dating modern phylogenies. A precise redescription of the fossil was conducted and its morphology and phylogenetic position was discussed. No synapomorphic characters could be identified, warranting an inclusion in an already established chalcidoid family. In fact, none of the autapomorphies for Chalcidoidea could be recognized, necessitating a revised systematic placement in the Proctotrupomorpha. In the second chapter, several fossils in amber are described that grant insights in the early evolution of Chalcidoidea and the morphological diversity of Cretaceous lineages. Morphological characters are studied to answer the question of plesiomorphic character states in Chalcidoidea, aiding to understand their early evolution. The phylogenetic placement of these fossils is discussed, to provide hypotheses on the diversification of the superfamily, which so far has only few fossil representatives described from this time. Four fossils are made scientifically available that were found in 99 million year old Burmese amber. Those specimens are described in a new, extinct family, the Diversinitidae. This family exhibits a unique combination of plesiomorphic characters, not present in any other chalcidoid taxon, but lacks apomorphic characters. In total, three new genera and three new species are delimited and described. Phylogenetically relevant characters like the fully developed funicular segments, possessing multiporous plate sensilla, or the peg like cerci that improve our understanding of the early evolution of Chalcidoidea, are discussed based on the newly established family. A phylogenetic analysis based on morphological characters was performed. This analysis supported the monophyly of Diversinitidae, but left its exact systematic position within Chalcidoidea open. In the third chapter the focus shifts from the early evolution of Chalcidoidea towards the extant fauna, representing the diversity evolved since the Cretaceous. Exemplary, in the speciose family Pteromalidae the unknown diversity is examined to better understand the undiscovered species richness of parasitoid wasps. DNA barcoding is used to record and help identify previously unknown genera and species in Germany. Compared to the already known pteromalid fauna, 17 genera and 41 species are added as new records for Germany and the males of two species are described anew. The identified DNA barcodes were made available to enable the genetic identification of those species that have a high potential as indicators for nature conservation efforts due to their high host specificity. In the fourth chapter, the pertinent problem of cryptic diversity in Chalcidoidea is investigated. Via an extensive integrative taxonomic approach, the morphological species hypothesis is tested for one of the most abundant pteromalid species in Europe, Spintherus dubius. In this example, the benefit of combining different methods for species discovery and delimitation is highlighted. Genetic analyses of S. dubius reveal discrepancies between the morphological species concept and molecular data, indicating two potential species instead of one. The usage of an advanced morphological method, the multivariate ratio analysis, results in a confirmation of the molecular results, also exposing distinctive morphological characters per taxonomic unit. The examination of the host spectrum through rearing experiments further substantiates these findings, by revealing different host parasitoid affiliations. Altogether, this thesis showed that it is necessary to combine methods and examine different evolutionary points in time, to better understand the diversity of parasitoid lineages. Fossil taxa are important study subjects to examine the character evolution of any taxon, laying the base for phylogenetic research. The study of Diversinitidae highlights the plasticity of character states in Chalcidoidea, also providing evidence for plesiomorphic states. Their encompassing description and the redescription of P. wohlrabeae allow their incorporation into phylogenetic studies, to serve as solid anchor points in dating lineages and morphological evolution on the way towards extant diversity. Examining the extant fauna of Pteromalidae revealed the amount of diversity of species, for which the biology is often unknown. It is shown that molecular methods aid in the discovery of this diversity, opening possibilities for further research. It is affirmed that hidden diversity is even pertinent in abundant, well known species, with S. dubius being an example of cryptic diversity unveiled by integrative taxonomy.
Evaluating different management strategies to increase the effectiveness of winter cover crops as an integrated weed management measure
(2020) Schappert, Alexandra; Gerhards, Roland
Weed control in agricultural production systems is indispensable to achieve stable crop yields. Integrated cropping systems are demanding for preventive and ecologically harmless weed control measures in order to protect soil and water resources and to retard the selection of herbicide-resistant weeds. Well-established winter cover crops provide nutrient retention and soil protection and may effectively suppress weeds. This contributes to reduce chemical and mechanical fall- and spring-applied weed control practices. However, producers are cautious towards integrating cover crops in crop rotations, as their performance is related to environmental conditions and varies, therefore, significantly from season to season. To increase their integration into cropping systems, reliability on weed control by cover crops needs to improve. In the current study, management strategies such as i) the cover crop sowing method, ii) the selection of water deficit tolerating cover crop species, iii) cover crop species combinations, iv) the adjustment of the mulching date and v) tillage practices after cover crop cultivation were considered as possibilities to improve the effectiveness of cover crops to control weeds during cultivation and in the subsequent cash crop. Within the first and the second publication, the general weed and A. myosuroides control ability of a cover crops mixture during and after cultivation were compared in the field with various fall-applied tillage methods and glyphosate treatments. Due to the development of highly competitive cover crop stands, weeds were suppressed by 98% and A. myosuroides by 100% during cultivation. Therefore, cover crops were more efficient compared to glyphosate application(s), non-inversion and inversion tillage and revealed a great potential to reduce or even replace chemical and mechanical fall-applied weed control measures. The efficient A. myosuroides control during the cover crop cultivation remained until spring barley harvest. This quantifies cover crops to complement herbicide resistance management strategies. In contrast, due to the weak cover crop performance during fall-to-winter within another two experiments included in the second article, weed suppressive effects of cover crops disappeared after the cultivation of cover crops. This might have been the reason why reduced tillage and adjusted mulching dates in spring failed in contributing to expand weed suppressive effects of cover crops in these experiments. Cover crop mixtures are attributed to show a greater resilience against unfavorable conditions than pure cover crop stands which is expected to result in an increased weed suppression ability. Within article three, the weed control efficacy of pure cover crop stands was compared with species mixtures. Pure stands of Avena strigosa Schreb. and Raphanus sativus var. oleiformis Pers. provided the most efficient weed control with 83% and 72%, respectively. Cover crop species mixtures showed a weaker weed suppression ability than the most efficient pure stand. In order to improve the weed control ability of cover crop mixtures, it was evaluated that the species selection is more relevant than the species diversity. Thereby, environmental requirements, such as water and temperature demand, and weed suppression mechanisms should be considered. Weed suppression of mixtures was improved by increasing the proportions of A. strigosa and R. sativus var. oleiformis, as they were showing a susceptibility for dry conditions and combine a strong competition for resources and allelopathic interference with weeds. Within the fourth article, it was explored whether a low susceptibility of single cover crop species to water-limitations accompanies an improved weed suppression ability. A. strigosa and Sinapis alba L. showed differing suitabilities to cope with water-deficit in the greenhouse. A relation between weed suppression and water demand of cover crops at the field was not identified. Although the weed control ability of cover crops is generally narrowed under water-limited conditions, the weed suppression potential of individual species seems to be independent of their water supply. The adjustment of the cover crop sowing method, the consideration of species-specific requirements and the mixing strategies, were evaluated as being important to improve the resilience of cover crops against severe environmental conditions and their weed control ability. Investigations of cover crop mixtures with respect to single component species, their mixing ratios and seed densities, might further increase the absolute and average effectiveness of cover crops as an integrated weed management practice.
Fernerkundungsgestützte Analyse und Bewertung ökologischer Auswirkungen des Anbaus von Bioenergiepflanzen auf die Agro-Biodiversität anhand der Modellierung der Habitatansprüche der Feldlerche (Alauda arvensis)
(2017) Schlager, Patric; Schmieder, Klaus
For the first time in 2002, the transformation of the conventional energy system into a system based on renewable energies was politically and legally decided in Germany. On the regional level numerous communities and municipalities followed this decision by voicing their own political resolutions, addressing the coverage of energy consumption with renewable energies. Their implementation is accompanied by a spatial expansion of bioenergy crops which lead to a controversial discussion about food safety, biodiversity and landscape change. Framed by the above mentioned discussion, this study assesses potential changes of skylark (Alauda arvensis) occurrence caused by a spatial expansion of bioenergy crops in the municipality of Schwäbisch Hall, Germany. The skylark was selected due to the comprehensive state of research about skylarks, their endangerment (“Red list of German breeding birds”), and the status as umbrella species for open agricultural landscapes (skylarks typically avoid vertical structures like hedges or edges of forests). The latter emphasizes their role as representatives for other species which are potentially affected by an expansion of bioenergy crops. This study is based on a stratified bird monitoring scheme of Baden-Württemberg, which was developed during a project that aimed to set up an indicator for species richness and was financed by the Bundesministerium für Ernährung, Landwirtschaft und Verbraucherschutz (BMELV). From the bird monitoring scheme, the stratum, which covers the municipality of Schwäbisch Hall, was extracted and served as a base for the development of a Generalized Linear Habitat Model of the skylark. In order to assess potential habitat changes caused by an expansion of bioenergy crops, Schwäbisch Hall was mapped with an airborne remote sensing technology in 2011. The resulting aerial images were transformed into orthophotos and later classified (focusing on agricultural areas) with an object oriented image analysis approach. Based on the outcomes of the habitat association model and the land use classification, skylark territories were predicted for 1 km² plots covering Schwäbisch Hall. For an in-depth understanding of ecological impacts from expanded bioenergy cropping, a bioenergy scenario was developed considering § 17 BBodSchG (national soil protection act) and regional food security. Based on the scenario, skylark territories were predicted for 1 km² plots covering Schwäbisch Hall. The most reasonable habitat association model resulted in a negative binomial Generalized Linear Model with the predictors winter sown crops and mean patch size per plot. Model performance was assessed by Wald z-statistics with p-values, ANOVA, explained variance, theta, residuals, AIC, and independent field data. Field data was only available for one plot. Therefore, the field data only indicate model performance. The comparison of the model predictions with the field data resulted in an accuracy of 92.21%. The land use classification resulted in the following five classes: 1. winter sown crops (33985.78 ha), 2. maize (9621.36 ha), rapeseed (2952.36 ha), unidentified crops (7244.18 ha), and grassland (30720.88 ha). Grasslands were not mapped by remote sensing techniques, but taken from a digital landscape model. Accuracy assessment showed an overall accuracy of 89.16 % and 0.78 kappa statistics. Prediction of skylark territories based on the land use classification of 2011 resulted in 46269 territories, or a mean density of 8.4 territories per 10 ha on agricultural areas and 5.4 territories per 10 ha on agricultural and grassland combined areas. The scenario assumed a three partite crop rotation (maize, rapeseed, winter sown crops) and a mean value of 0.17 ha per inhabitant for food security. Areas for fodder production were considered in course of the calculation of food security because Schwäbisch Hall is characterized by many livestock farms, which made it necessary to avoid conflicts between potential bioenergy sites and areas for fodder production. Considering the above mentioned assumptions, Schwäbisch Hall has a bioenergy potential of 5955 ha for maize and 15033 ha for rapeseed cropping. The results of the bioenergy scenario were randomly distributed to the land use polygons which resulted from the remote sensing analysis. With that, prediction of skylark territories based on the bioenergy scenario was feasible. Skylark territories for the bioenergy scenario resulted in 36472 territories, or a mean value of 6.8 territories per 10 ha on agricultural areas and 4.3 territories per 10 ha on agricultural and grassland combined areas. Considering both land use options, skylark territories declined by 8797 in total numbers or by 19.43 % in relative numbers. In addition to the land use options described above, landscape structure and territory distribution were analyzed based on six landscape units (Naturräumliche Haupteinheiten) covering the municipality of Schwäbisch Hall. The analysis revealed an agriculturally dominated northwestern part, with high numbers and mean values of skylark territories, and a grassland/forest dominated southeastern part, with lower numbers and mean values of skylark territories. The relative decline of these territories between the two land use options within the landscape units resulted approximately in 22 % in the northwestern and approximately 11-15 % in the southeastern part. The results indicate that an expansion of bioenergy crops will have negative effects on breeding birds in open agricultural landscapes which already suffer from degraded habitat conditions. Based on the assumptions of this study, skylark territories will decline by approximately 20 % in comparison to 2011. Yet, considering the results of the indicator report of the German National Strategy on Biodiversity (BMU 2010) and the European Bird Census Council the baseline of 2011 already represents a degraded situation in terms of habitat quality for agricultural breeding birds.
Functional larval-parasitoid biodiversity in apple orchards as benchmark for management intensity and potential instrument for ecological amelioration of Iranian apple production
(2019) Lashkari-Bod, Abdullah; Zebitz, Claus P. W.
Although a consensus through the concept of sustainable agricultural production and its indicators to assess its functionality varies, it is expected to be long-term and reliable. The sustainability would change temporarily and spatially. It is influenced by political, social and economical is-sues, which reveals its interdisciplinary essence in concert with farming strategies and practices to produce human food. The management of plant protection is capable to impose unsustainability into farming system. The frequency and intensity of unsustainable practices would result into devastating effects on diversity and abundance of beneficial arthropods. The communities of natural enemy may promote sustainable management, but the anthropogenic interventions such as broad-spectrum pesticide applications would distort the essence of self-monitoring of natural invertebrates as regulators. The conventional agricultural management makes the habitats to be simplified through food webs and ecological complexities, which lead to species loss (extinction or emigration) and consequently to species interactions (connectance). The ecologically based management such as integrated pest management (IPM) would focus to maintain species and increase diversity in natural communities, which contributes to sustainable approach as alternative versus conventional agriculture. The negative effects of chemical pesticides would dramatically decline the ecosystem process and affect the energy flow among different trophic levels, which is manifested as functional rates in local or regional scale of ecosystem. The human-manipulated areas create negative consequences on the ecosystem functionality through vanishing the key natural resources (i.e. shelter, food provision, and alternative host prey), which affect maintaining natural enemy communities. The complementarity effects of antagonist communities can lead a synergetic impact on pest control, when biodiversity is conserved through vegetation, rational bio-pesticide application, and ecological infrastructure, the functional traits (richness and evenness) among interacting species will be improved. Furthermore, the intensified agriculture would arise pest outbreaks or convert a secondary and unimportant pest into a serious one. The antagonistic communities may represent as bio-indicators. The presence or absence of higher trophic levels and their complexes would reflect biotic or abiotic changes in the environment, which would eventually be expressed as parasitism or consumption rate. The scope of current research is limited to indicators of sustainability through pest management and does not comply a holistic approach on ecological, political, social, and economical managements. The preliminary results focus on the status quo of plant protection in Iran and biodiversity indices in Germany used to compare the different farm systems to show how the management can affect the community components and their interactions. The environmental and anthropogenic impacts on biodiversity of beneficial arthropods in different orchard management conducted in Germany, where the accessibility of abandoned apple orchards is more prevalent than Iran. To evaluate the impact of conventional intensive management vs. ecologically based sustainable practices on invertebrate beneficial community, a comparative study was conducted to assess food web pattern of larval-parasitoid communities, biodiversity indices, and parasitism rate in response to apple orchard by four different managements. Field samplings were occurred during 2011-2015 in Baden-Württemberg, Germany. The orchard managements were distinguished based on the frequency and intensity of pesticide applications into the farming system. The categories of orchard management were managed (organic and integrated), and Streuobst (semi-abandoned orchard), which were situated in Denzlingen, Emmendingen, Goldener Grund, Hohenheim research center, Ilsfeld, Lake Constance, Neuhausen, Plieningen, Rommelshausen, and Scharnhausen. The sampling was conducted by installation of corrugated cardboard and random observation to collect larval caterpillars (Tortricidae and Gelechiidae). The collected samples were transferred to lab to rear adult parasitoids and further studies on taxonomic affiliation. Out of 7,923 healthy host larvae collected, totally 324 parasitoid individuals from three sub-families of Braconidae, Ichneumonidae, and Perilampidae were found. Four parasitoid species were found positive host-density dependent, the rest of the parasitoid species showed no densi-ty-dependency or were found in too small numbers. The highest richness, abundance, and evenness of larval-parasitoids were found in Streuobst orchards (i.g. Plieningen), which received no to minimal pesticide inputs. The interaction diversity of food webs (connectance) in Streuobst showed the highest number of trophic links in response to other orchard managements where the commercial (conventional) orchards harbor no to the least biodiversity indices of beneficial arthropods. Percentage similarity also assessed to depict the similarity of larval-parasitoid community structures in different managements. It was revealed the orchards with the same management contain similar parasitoid compositions. To describe and analyze the information on apple growing management, circumstances of plant protection, pest status, and major obstacles to initialize sustainable production in Iran, a questionnaire was designed to survey 39 apple growers from East-Azerbaijan, Fars, Isfahan, Tehran, and W. Azerbaijan in July 2014. It was found that management of the orchards mostly is under the supervision of the apple growers. Farmers in Isfahan suffer a road infrastructure to have an access to the nearest market to sell their product indicating an economic monopoly. The distance to experts affects the intensity of pesticide application by farmers. The conventional agriculture is prevailing in all provinces and access to bio-pesticides highly limited to Tehran. Totally 29 pesticides were used against different fruit pests in Iran. The most damage intensities occurred by pests in province scale and weeds in regional scale. The outbreak of secondary pest Tetranychus urticae as key one indicates human perturbations in Iran’s farming system. Tehran province enjoyed diverse apple cultivars contrary to other provinces, which are poor in diversification. The predominant outlook to choose a cultivar among apple growers was marketing.
Genetische Diversität von Echinococcus granulosus sensu stricto
(2017) Ebi, Dennis; Mackenstedt, Ute
The dog tapeworm Echinococcus granulosus sensu stricto, distributed worldwide, is the most important agent of human Cystic Echinococcosis, a zoonotic disease which is considered as one of the priority ‘neglected zoonotic diseases’ by the World Health Organisation. The parasite is known from a large number of host species and is conventionally subdivided into several genotypes. The epidemiological consequences of the variation, however, are still unknown. In the last years several studies on the intraspecific variation of this parasite were published. Most of these studies were based on small numbers of isolates from geographically restricted regions, so that the relevance of that diversity concerning pathogenicity, host specificity, transmission cycles and biogeography is still little understood. To achieve a comprehensive estimate of its genetic diversity, 1085 isolates of E. granulosus s.s. from humans and animal hosts originating from widely different regions of the world were analyzed for the sequence polymorphism of a 1609 bp fragment of the mitochondrial cox1 gene. For analysis haplotype networks, diversity and neutrality indices of subpopulations of different geographic origin were compared. To improve the analytical efficiency of the sequence-data, a LabVIEW application was written. It could be shown that most diverse sub-population is found in the Middle Eastern region and that the genetic diversity is lower in the other analyzed regions, which confirms a previous tentative hypothesis on the origin of the domestic cycle of E. granulosus s.s. in that region. Records of identical haplotypes in different regions, inclusion of published data, calculation of parameters of population genetics and haplotype network analysis led to hypotheses explaining the distribution history of E. granulosus s.s.. This in line with fossil and molecular data on domestic sheep as the principal final host. A set of new and easily calculable genetic diversity indices were developed and their added value was explained. Additionally, a statistical resampling experiment was programmed which showed that at least 40 well distributed samples are necessary to provide a reliable estimate of the genetic diversity of the parasite in a region. Using an extension for that software, it was shown that the newly developed diversity indices do not strongly depend on the number of analyzed samples, and provide appropriate tools to assess the genetic diversity of parasite populations.
Integrative taxonomy of platygastrine wasps of Germany
(2023) Awad, Jessica; Krogmann, Lars
In the context of the sixth mass extinction, our understanding of insect decline is severely limited by a lack of information on biodiversity. Many highly abundant and diverse insect groups remain unidentifiable to species or even to genus. The parasitoid wasp superfamily Platygastroidea is one such “dark taxon”. The taxonomic impediment is especially severe in the Palearctic Platygastrinae due to the proliferation of names with vague concepts. Platygastrine wasps parasitize the hyper-diverse Cecidomyiidae (Diptera), suggesting that their species richness may be correspondingly high. Revisionary work is needed to identify named species and to discover new ones. This work applies integrative taxonomic methods to address the most pressing problems within the subfamily. The research presented in this dissertation focuses on Europe, particularly Germany, which is the current center of insect decline research as well as a historical center of platygastrine taxonomy. As part of this work, historical descriptions and their associated type material were examined and clarified so that further revisionary work can occur. The dissertation is structured in five chapters, of which two are published and three are unpublished. The first chapter reviews 18 genera of Platygastridae described by Arnold Förster (1856), most of which represent distinct and recognizable lineages. The study provides their taxonomic history, diagnostic remarks, English translations, and illustrations of important specimens from the Förster collection in the Natural History Museum Vienna. The collection also includes original exemplar specimens of European species whose types have been lost. Potential neotypes and lectotypes from this material are noted, with the aim of improving nomenclatural stability in the group. Potential neotypes were found for Amblyaspis forticornis (Nees, 1834), Isocybus grandis (Nees, 1834), Platygaster striolata Nees, 1834, and Trichacis tristis (Nees, 1834). Lectotypes will be designated for Platygaster spinigera Nees, 1834, which will be transferred to Leptacis, and for Platygaster corvina Förster, 1861, with Platygaster henkvlugi Buhl, 1996 treated as a junior synonym. Synopeas mutica (Nees, 1834) should be transferred back to Platygaster. The second chapter addresses generic concepts within Platygastrinae sensu Ashmead. Part of Platygastrinae (former Inostemmatinae sensu Ashmead) was reviewed and keyed by Masner & Huggert (1989). However, more than half of the genera in the subfamily, including the vast majority of species, have not been revised. A working key to 14 major world genera, the first of its kind, is provided. An additional six genera and three subgenera of uncertain placement are discussed. The third chapter focuses on nomenclatural problems in the genus Platygaster Latreille, which is the type genus for its subfamily, family, and superfamily. It is also the largest genus in Platygastroidea with nearly 700 species, and recent evidence indicates that it is not monophyletic. It is necessary to establish the identity of the type specimen, as well as the identities of the 13 generic junior synonyms and four subgenera, in order to proceed with taxonomic divisions. The type specimen Scelio ruficornis Latreille, 1805, lost to science for 192 years, was rediscovered. However, it does not belong to the prevailing concept of Platygaster, but to Isocybus Förster, which has extreme taxonomic ramifications. The proposed solution would replace the type species of each genus in order to retain prevailing usage and prevent widespread confusion. A petition is presented to designate Epimeces ensifer Westwood as the type of Platygaster and Scelio ruficornis as the type of Isocybus. In the fourth chapter, the genus Trichacis Förster is revised for Europe. Examination of historical and modern collections combined with DNA barcoding revealed the presence of only a single species in Europe, Trichacis tristis (Nees, 1834), redescribed here. The results suggest that T. tristis has 14 junior synonyms: T. abdominalis (Thomson, 1859); T. bidentiscutum Szabó, 1981; T. didas (Walker, 1835); T. fusciala Szabó, 1981; T. hajduica Szabó, 1981; T. illusor Kieffer, 1916; T. nosferatus Buhl, 1997; T. pisis (Walker, 1835); T. persicus Asadi & Buhl, 2021; T. pulchricornis Szelényi, 1953; T. quadriclava Szabó, 1981; T. remulus (Walker, 1835); T. vitreus Buhl, 1997; and T. weiperti Buhl, 2019. Four species should be transferred to Amblyaspis Förster: T. afurcata Szabó, 1977, T. hungarica Szabó, 1977, T. pannonica Szabó, 1977, and T. tatika Szabó, 1977. Intraspecific variation, biological associations, and taxonomic history are discussed. DNA barcodes are provided and analyzed in the context of worldwide Trichacis and its sister genus Isocybus Förster. The fifth chapter examines platygastrid diversity in Germany in the context of insect decline. DNA barcodes indicate the presence of 178 observed species, with an estimated total of 290. GBOL sampling captured an estimated 93.7% of total species richness, but only 45.8% of rare species. A case study from Isocybus compares historical specimens, DNA barcode vouchers, and ecological data to illustrate the possible decline of a wetland parasitoid species. Altogether, the research demonstrates the importance of historical material, especially type specimens, in understanding biodiversity through time, and provides an essential taxonomic foundation for much-needed modern identification resources for Platygastrinae in the western Palearctic and beyond.
Integrative taxonomy, systematics and biogeography of geometrid moths in a Middle Eastern biodiversity hotspot
(2023) Wanke, Dominic; Krogmann, Lars
Iran is an important biodiversity hotspot in the world. Recent studies have shown that two of the 36 global biodiversity hotspots are located in Iran: The Irano-Anatolian and the Caucasian hotspots. These two hotspots include parts of the two mountain ranges in Iran, the Alborz Mountains and the Zagros Mountains, which are crucial for the biodiversity, hosting a large number of endemic species. However, climate change and anthropogenic activities threaten its diversity. This study uses geometrid moths as a model group to better understand general patterns of biodiversity and zoogeography in Iran. Geometridae are suitable for such studies and scientifically interesting for several reasons: The family is species-rich with nearly 24,000 known species worldwide (539 known species in Iran), the species have short life-cycles and thus react quickly to environmental changes, and they occupy specialized ecological niches. Knowledge of Palearctic geometrid moths is rather advanced compared to other regions. The Western Palearctic, in particular, has been the target of considerable research. However, this is not the case for regions in the Middle East and Central Asia, where much is still unknown and further research is crucial. To fill this gap for geometrid moths in this region, data on their species richness and distribution patterns were collected to reveal regions with special faunal elements. Therefore, this dissertation consists of three parts, each of which contributes an essential element to achieve these goals. The first part deals with the taxonomic problems of partially species-rich and morphologically very difficult genera within the three subfamilies Sterrhinae (Problepsis, Scopula, Cinglis, Pseudocinglis, Scopuloides, Glossotrophia, Zygophyxia); Geometrinae (Xenochlorodes); and Ennominae (Nychiodes, Synopsia, Synopsidia, Eumera). Type specimens and original descriptions were used for critical revisions to understand the diagnostic characters of the species. Additionally, large series of specimens from many different museums and private collections were examined to highlight morphological variations. Using an integrative taxonomic approach that includes morphological and molecular data, a total of one new genus and four new species were described and 37 taxonomic changes (e.g., new synonyms, new combinations) were made. The second part addresses genera with uncertain tribal affiliation or questionable taxonomic status, which were also partially targets of the taxonomic revisions. A multi-gene phylogenetic analysis was performed using one mitochondrial gene and up to nine nuclear genes, sequences generated as part of this work and sequences from published phylogenetic studies were taken to run the analyses. As a result, the genus Eumera was determined to belong to the tribe Prosopolophini, the genera Cinglis and Scopuloides were removed from synonymy with Scopula, two genera were synonymized (Glossotrophia, Pseudocinglis), and two species were transferred to a different genus (Problepsis wiltshirei, Aphilopota tyttha). In the third part, distribution data of Iranian Geometridae was used to identify biodiversity hotspots and regions of high endemism. In addition, a network-based method was used to divide the country into unique bioregions and highlight areas with specific faunal elements. As a result, an exceptional species richness was found along the two main mountain ranges, Zagros in the west and south and Alborz in the north. Considering only the endemic species, the southern mountain areas were identified as the most species-rich regions. The bioregionalization analysis also identified six main bioregions. Most of these bioregions reflect specific faunal structures and are in accordance with previous studies. This highlights the complex species composition in Iran and demonstrates the exceptional biodiversity of the country. In addition, our results indicated two transition zones between zoogeographical realms. Of the six zoogeographical realms defined by Wallace, three occur in Iran meeting in the south of the country: The Palearctic and Saharo-Arabian along the foothills of the Zagros Mountains and the Palearctic and Oriental in southeastern Iran. At these transition zones, Iran has very specific faunal elements of the Geometridae, which makes these zones important for conservation. Overall, this work contributes to a better understanding of the biodiversity of geometrids in Iran and neighboring countries. It serves as a resource for the identification of species, their distribution and habitats, which are of great interest for conservation efforts in Iran and neighboring countries.
Interactions of farming and plant biodiversity in weed control related ecosystem service provision and weed conservation
(2020) Schumacher, Matthias; Gerhards, Roland
There is evidence that diverse plant communities in terrestrial ecosystems are either more stable or more productive in terms of food web support and ecosystem service provision. In agro-ecosystems, characterized by high disturbance and external inputs, plant diversity and their services can only be provided by weeds. In the first study, vegetation recordings and farmer surveys were conducted in on-farm experiments in two regions of Southwestern Germany. The aim was to examine the effects of agricultural management on weed community composition, weed biodiversity and occurrence of rare arable weed species in cereal fields. Weed biodiversity was influenced mainly by crop species, herbicide use and farming system as well as nitrogen and light availability. Weed communities were quite similar in both study regions and dominated by Alopecurus myosuroides, Galium aparine, Viola arvensis, Polygonum convolvulus and Veronica persica. A redundancy analysis revealed that the weed community was mainly shaped by crop species, tillage, location in the field and timing of herbicide application. The results highlight the erosion of weed communities due to intensive agricultural practices and emphasize the conservation of weed biodiversity per se and rare arable weed species in particular. The next aim was to examine if this biodiversity is able to support weed control related ecosystem services, like the predation of weed seeds. The objectives of this study were to investigate the connection between weed biodiversity, Carabid beetle diversity and weed seed predation as well to evaluate the role of farming intensity in this sequence. For this purpose, on-farm experiments were performed on the Eastern Swabian Alb. A positive correlation between weed biodiversity and Carabid beetle diversity was identified as well as a pattern of medium Carabid beetle diversity providing the highest weed seed predation. There was no consistent influence of farming intensity on weed seed predation. The revealed connection between weed diversity, Carabid beetle diversity and weed seed predation highlights the role of plants in food web support and subsequent ecosystem service provision. The utilization of these services depends on the promotion of biodiversity by designing appropriate management strategies. In the next step, the general principles underlying ecosystem service provision by biodiversity, were conveyed to a cover cropping system. The aim was to test single sown cover crops and species mixtures in terms of weed suppression efficacy and reliability. For this purpose, cover crop species were sown singly and as mixtures in a field experiment. Lower weed dry matter and weed densities were found predominantly in treatments with favorable establishment and above-average biomass production. Mixtures performed much more homogeneous in regard to the measured parameters compared to single sown cover crops. The results suggest that, although particular single sown cover crops are more effective to control weeds than mixtures, mixtures are more reliable under changing conditions. Altering the species composition of cover crop mixtures according to more complementary traits might further improve their weed control efficacy. The results of this dissertation demonstrate the importance of plant biodiversity in the provision and reliability of weed control related ecosystem services, either by weeds themselves or by specifically designed cover crop mixtures. Furthermore, management factors influencing weed biodiversity were determined, which can aid in the creation of more sustainable management strategies for a diverse agroecosystem and the conservation of rare arable weed species.
Nachhaltigkeitsexzellenz in der Landwirtschaft: Mehr Sichtbarkeit für die versteckten Leuchttürme der Alltagspraxis
(2024-09) Gebhardt, Beate; Hellstern, Laura
Im Projekt NEAL wurde die Bedeutung von exzellenter Mikro-Nachhaltigkeit und die Rolle von Nachhaltigkeitsawards sowie weiterer unterstützender Instrumente einer nachhaltigen Transformation in der Landwirtschaft untersucht. Die Erkenntnisse des Projektes sollen landwirtschaftlichen Unternehmen, Verbänden sowie weiteren relevanten Akteuren der land¬wirtschaftlichen Wertschöpfungsketten eine Orientierung geben in den Fragen: • Welche Nachhaltigkeitsthemen benötigen in Zukunft ein größeres Augenmerk? • Wie können Landwirt*innen in ihrer Nachhaltigkeitstransformation gefördert werden? • Welche Rolle spielen Nachhaltigkeitsawards in der Nachhaltigkeitstransformation? Für das Forschungsprojekt NEAL wurden dazu (a) 310 Landwirt*innen und 59 landwirtschaftsnahe Verbände in einem bundesweiten Nachhaltigkeits-Crowd-Screening im Frühjahr 2022 online befragt und hierbei insgesamt 236 herausragende, awardwürdige Nachhaltigkeitsaktivitäten identifiziert, die in der Landwirtschaft bereits umgesetzt oder geplant werden. Mittels Awards-Matching und Clustering wurde (b) der webbasierte, interaktive CSR-Award Finder mit über 150 Wettbewerben erstellt und Ende 2022 online gestellt. Der CSR-Award Finder macht die Welt der Awards für Unternehmen übersichtlicher und einfacher zugänglich, insbesondere erleichtert dies den Zugang kleiner Unternehmen und landwirtschaftliche Betriebe. Zentrale Aussagen der Studie lauten: 1. Nachhaltigkeit ist für Landwirt*innen ein relevantes Thema und viele „versteckte“ nachhaltige Tätigkeiten werden auf den befragten Betrieben bereits umgesetzt. 2. Bio-Betriebe zeigen sich als Vorreiter von Nachhaltigkeitsexzellenz in der Landwirtschaft. 3. Bodennutzung, Biodiversität, regionale Wertschöpfung und Tierwohl sind wichtige Bereiche, in denen viele nachhaltigkeitsbezogene Maßnahmen von Landwirt*innen umgesetzt und als besonders hervorgehoben werden. 4. „Blinde Flecken“ in Nachhaltigkeitsansätzen korrespondieren mit Bewertungen der Landwirtschaft.. 5. Leuchttürme der Mikro-Ebene kommen auf der Makro-Ebene kaum an. 6. Eine heterogene und multifunktionale Landwirtschaft benötigt vielfältige, multiple Instrumente zur Förderung von Nachhaltigkeit auf Betriebsebene. 7. Nachhaltigkeitstransformation in der Landwirtschaft benötigt mehr gemeinsame An-strengungen. 8. Nachhaltigkeitsexzellenz in der Landwirtschaft benötigt mehr Mut und Sichtbarkeit. Die Ergebnisse im Projekt NEAL unterstreichen: Ein Ansatz alleine ist nicht ausreichend. Aufgrund der Heterogenität der landwirtschaftlichen Betriebe gilt dies gerade auch für die Landwirtschaft. Sustainable Finance und Awards sind dabei zwei verschiedene Ansätze bzw. Instrumente, die beide als wichtig und unterstützend gelten, um die Nachhaltigkeitstransformation landwirtschaftlicher Systeme und Betriebe voranzubringen. Beiden Ansätzen wird bescheinigt, ein wichtiges Instrument unter vielen zu sein, aber singulär einen eher geringen Hebel zu haben, da nicht alle landwirtschaftlichen Betriebe damit eingebunden werden können oder sich dadurch angesprochen fühlen. Die Ergebnisse im Projekt NEAL zeigen außerdem, Awards sind in die Toolbox der bekannten Instrumente und Anreize zur Stärkung der Nachhaltigkeitstransformation einzubinden. Sie stehen damit neben ökonomischen Anreizen im Markt oder regulativen Anreize, die vom Staat gesetzt werden. Awards setzen am Positiven und an der Sichtbarmachung des Vorbildhaften und Innovativen in der Landwirtschaft an. Sie können damit das verborgene Besondere, die nachhaltigen Aktivitäten und die versteckten Leuchttürme in der Landwirtschaft, nach außen tragen und zum Leuchten bringen, und damit die Nachhaltigkeits-Motivation der Landwirt*innen erheblich steigern.
Peru Botanische Exkursion 2008
(2010) Dinter, Ina; Zimmermann, Reiner
The botanical excursion to Peru, a global hotspot of biodiversity, provides an overview of the climatic, regional and plant ecological situation of the equatorial neotropics. The areas visited cover the hyper arid coastal deserts, the dry and cold andine Puna, the Amazon lowland rainforests and the seasonal dry forests of North Peru. The excursion report presented was compiled from presentations and protocols of the participants and contains the list of plants found at each site visited.
Reconciling indigenous and scientific ecosystem and soil fertility indicators in swidden systems of Northern Thailand
(2021) Tongkoom, Krittiya; Cadisch, Georg
Crop rotations in today’s swidden systems of Northern Thailand typically include five to ten years of fallow. Regarding ecosystem functions, these systems are relatively close to secondary forests when compared to modern agricultural systems; but they are under pressure for intensification, i.e. shortened fallow periods. In general, criteria are needed to decide whether fallow duration can be reduced, safeguarding ecosystem restoration and provision of food and income for farmers. Acknowledging that a comprehensive assessment would cover multiple aspects, our study focuses on the role of fallow duration on tree community succession and use abundances of tree species considered as soil fertility indicators. We studied recovery indicators of tree communities at two potential broad-leaved forest climax sites that differ in soils, forest type and agricultural intensification: An intensive system of one-year upland rice, then one- to two-year maize cultivation with synthetic inputs followed by six years fallow; and an extensive system with one-year upland rice cultivation without agrochemicals and ten years fallow. In a case study village of extensive site, we investigated in how far abundance of indicator tree species corresponded to measured soil fertility parameters and whether an extended list of indicator species could improve prediction of these soil properties. Contrasting systems were chosen to test the applicability of our indicators, not to compare their management practices. From 2010 to 2011, eight variables related to stand structure and tree diversity and four soil properties were either monitored or surveyed in chronosequence plots representing different fallow ages. For each variable, means per fallow year were compared by least squares means (LS-means), and quadratic regressions from mixed models were fitted. Significant differences between LS-means and optima of regressions served to distinguish fallow stages and served as indicators of recovery and system stability. Stepwise multiple regressions confirmed fallow age as main determinant for most variables. Tree species indicator also identify by the component of multiple linear regressions function of each interested soil properties. Numbers of tree species and diversity index recovered to levels of the previous rotation within the respective fallow time, but in both systems were far from climax communities, probably due to seed-bank depletion and shift toward resprouting species. While species dominance changed over time in the extensive system, the intensive system was dominated by a single species. In the extensive system only tree density passed a peak during the fallow period, while biomass-related variables approached plateaus. In combination with the replacement of early fallow species, this points to the onset of competition and transition between successional stages. For the intensive system, no structural variable passed a maximum. With only one of eight indicators on the extensive site fulfilling the statistical criterion of passing a peak during the prevailing fallow time, reducing fallow periods is not recommended for our cases. Generally, combining LS-means and quadratic regression allowed assessing fallow duration based on distinct successional stages at different sites. The approach should include various relevant site-specific indicators, in our case representing biomass and carbon storage, species and structural diversity, considered crucial for both sites. From interview on the extensive site, farmers listed 11 tree species that relate to certain soil quality related properties. They named indicators of good soils for cropping, inappropriate soils for upland rice cropping and hard soils. Botanical tree inventories on 135 plots of one to ten years fallow age were conducted. Abundances of farmers’ indicator on one hand as well as inventory species on the other were introduced into different regression models to predict soil fertility parameters measured on the same plots. Both models were then compared regarding predictive power. Measured fertility parameters such as soil organic matter (SOM), pH, plant available phosphorus (Pav) - related to farmers’ criteria ‘good soil’ or inappropriate for rice cropping’ - as well as bulk density (BD, for ‘hard soil’), changed significantly during the fallow period, initially towards temporary pessima in years 6 to 7 followed by recovery towards year ten. Most indicator species, like Macaranga denticulata for Pav or Dalbergia cultrata for SOM, were clearly related to the soil quality characteristics attributed to them by farmers. Only in one case a species used as farmer indicator for hard soils was selected by multiple regression as predictor for high Pav. Including all tree species found during inventories into multiple regressions significantly improved predictions of measured soil parameters by AIC > |2|. Ten additional species from the survey model had potential to improve the farmer indicator model. Relative density, i.e. abundance of indicator tree species over abundance of all species, did not always match soil properties dynamics, so that the use of the regressions appears more informative for cropping decisions. Our approach to relate indicator species and measured soil parameters is not site-specific, but parameters are. Applicability of the approach could be extended if further farmer criteria such as weed suppression, represented by tree structure parameters as predictors of adequate fallow age, would complement soil fertility indicators. Based on the development of the multiple indicators of recovery of ecosystem services and soil fertility, it is not recommended to reduce fallow age at the two investigated study sites.
Simulating the impact of land use change and climate change on the supply of ecosystem services in a rubber-dominated watershed in Southwestern China
(2020) Thellmann, Kevin; Asch, Folkard
This cumulative PhD thesis investigates the expansion of rubber (Hevea brasiliensis Müll. Arg.) plantations and the ensuing multiple impacts on biodiversity and the supply of ecosystem services (ESS) in a mountainous watershed in Xishuangbanna Prefecture, Southwestern China. In recent decades, the study area, the Nabanhe Reserve, saw the expansion of rubber plantations and the loss of extensive forest areas, which led to a substantial decline in ESS. Workshops with regional stakeholders resulted in the development of three future land use scenarios for Nabanhe Reserve (2015 – 2040), varying in their degree of rubber expansions, management options and reforestations efforts. In the first study, the InVEST (Integrated Valuation of Ecosystem Services and Trade-offs) modeling framework was used to analyze the impact of these rubber expansion scenarios on selected ESS: sediment retention, water yield, habitat quality, and carbon sequestration. In addition, a model for assessing potential rubber yields was developed and implemented in ArcGIS. The analysis also included different statistical weighting methods to include rankings for the preference of ESS from three contrasting stakeholder groups (prefecture administration, tourists, off-site citizens). The study concludes that the integrated ESS indices would be overestimated without the inclusion of the stakeholder groups. The second study introduced a new method to identify potential tipping points in the supply of ESS. Here, time-series data derived from InVEST have been combined with a sequential, data-driven algorithm (R-method) to identify potential tipping points in the supply of ESS within two contrasting scenarios of rubber expansion in Nabanhe Reserve. The tipping point analysis included hydrological, agronomical, and climate-regulation ESS, as well as multiple facets of biodiversity. The model results showed regime shifts indicating potential tipping points, which were linked to abrupt changes in rubber yields, in both scenarios and at varying spatial scales. The study concludes that sophisticated land use planning may provide benefits in the supply of ESS at watershed scale, but that potential trade-offs at sub-watershed scales should not be neglected. The third study focused on modeling hydrological ESS (water yield and sediment export) in Nabanhe Reserve under multiple scenarios of land use and climate change in order to assess how both drivers influence the supply of these ESS. Three rubber expansion scenarios were analyzed in combination with multiple climate change scenarios using the InVEST modeling framework. Simulation results showed that the effect of land use and land management decisions on water yield in Nabanhe Reserve are relatively minor (4% difference in water yield between land use scenarios), when compared to the effects that future climate change will exert on water yield (up to 15% increase or 13% decrease in water yield compared to the baseline climate). Changes in sediment export were more sensitive to land use change (15% increase or 64% decrease) in comparison to the effects of climate change (up to 10% increase). The study concludes that in the future, particularly dry years may have a more pronounced effect on the water balance in Nabanhe Reserve as the higher potential evapotranspiration increases the probability for periods of water scarcity, especially in the dry season. In conclusion, the studies showed detrimental consequences induced by rubber expansions for all assessed ESS, with the exception of rubber yields. Further continuing the trend of rubber expansions in the study area is not the best option in terms of integrated ESS supply on a landscape scale. Land use planning alternatives, such as rubber expansions restricted to suitable areas only, in combination with reforestation efforts at less suitable locations, may be used to keep crucial environmental functions intact. Policy regulations at the local level, if properly assessed with spatial models and integrated stakeholder feedback, have the potential to buffer the typical trade-off between agricultural intensification and environmental protection. The implementation of these regulations might still pose a considerable challenge. The methods introduced in this Dissertation can easily be transferred to regions facing comparable land use situations, as InVEST and a large amount of the utilized spatial datasets are freely available.
Status Quo und Potentiale des ökologischen Heil-, Kosmetik- und Gewürzpflanzenanbaus in Baden-Württemberg : Studienbericht & Supplement
(2022) Gebhardt, Beate
At first glance, changing social demands, such as the desire for more biodiversity and a more sustainable use of agricultural land, offer new opportunities for the organic cultivation of medicinal, cosmetic and spice plants. The increased health awareness and interest of consumers in organic food, natural cosmetics and alternative healing methods such as phytotherapy, lead to expectations of new product developments and market growth, both in the production of raw materials and in their processing and access to new markets and value chains. However, it is difficult to assess to what extent such potentials can actually be used by farmers and firms in Baden-Württemberg. On the one hand, only few data and studies on the status quo of medicinal and aromatic plant cultivation in Baden-Württemberg have been published. On the other hand, it is unclear which constraints exist for the further development of the organic medicinal and aromatic plant sector. This is the background for a recent status review in this report, which was carried out by the Department of Agricultural Markets at the University of Hohenheim from June 2021 to February 2022 funded by the Ministry of Rural Areas and Consumer Protection (MLR) Baden-Württemberg. The cooperation partners are the Centre for Organic Agriculture, University of Hohenheim, and the Netzwerk Kräuter Baden-Württemberg e.V. (Herb Network Baden-Württemberg).