Institut für Kulturpflanzenwissenschaften

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Assessing the efficiency and heritability of blocked tree breeding trials
(2024) Piepho, Hans-Peter; Williams, Emlyn; Prus, Maryna
Progeny trials in tree breeding are often laid out using blocked experimental designs, in which families are randomly assigned to plots and several trees are planted per plot. Such designs are optimized for the assessment of family effects. However, tree breeders are primarily interested in assessing breeding values of individual trees. This paper considers the assessment of heritability at both the family and tree levels. We assess heritability based on pairwise comparisons among individual trees. The approach shows that there is considerable heterogeneity in pairwise heritabilities, primarily due to the differences in both genetic as well as error variances among within- and between-family comparisons. Our results further show that efficient blocking positively affects all types of comparison except those among trees within the same plot.
Assessment of different methods to determine NH₃ emissions from small field plots after fertilization
(2025) Götze, Hannah; Brokötter, Julian; Frößl, Jonas; Kelsch, Alexander; Kukowski, Sina; Pacholski, Andreas Siegfried; Anderson, William A.
Ammonia (NH₃) emissions affect the environment, climate and human health and originate mainly from agricultural sources like synthetic nitrogen fertilizers. Accurate and replicable measurements of NH₃ emissions are crucial for research, inventories and evaluation of mitigation measures. There exist specific application limitations of NH₃ emission measurement techniques and a high variability in method performance between studies, in particular from small plots. Therefore, the aim of this study was the assessment of measurement methods for ammonia emissions from replicated small plots. Methods were evaluated in 18 trials on six sites in Germany (2021–2022). Urea was applied to winter wheat as an emission source. Two small-plot methods were employed: inverse dispersion modelling (IDM) with atmospheric concentrations obtained from Alpha samplers and the dynamic chamber Dräger tube method (DTM). Cumulative NH₃ losses assessed by each method were compared to the results of the integrated horizontal flux (IHF) method using Alpha samplers (Alpha IHF) as a micrometeorological reference method applied in parallel large-plot trials. For validation, Alpha IHF was also compared to IHF/ZINST with Leuning passive samplers. Cumulative NH₃ emissions assessed using Alpha IHF and DTM showed good agreement, with a relative root mean square error (rRMSE) of 11%. Cumulative emissions assessed by Leuning IHF/ZINST deviated from Alpha IHF, with an rRMSE of 21%. For low-wind-speed and high-temperature conditions, NH3 losses detected with Alpha IDM had to be corrected to give acceptable agreement (rRMSE 20%, MBE +2 kg N ha−1). The study shows that quantification of NH₃ emissions from small plots is feasible. Since DTM is constrained to specific conditions, we recommend Alpha IDM, but the approach needs further development.
Bird species richness and diversity responses to land use change in the Lake Victoria Basin, Kenya
(2024) Mugatha, Simon M.; Ogutu, Joseph O.; Piepho, Hans-Peter; Maitima, Joseph M.
The increasing demand for cultivated lands driven by human population growth, escalating consumption and activities, combined with the vast area of uncultivated land, highlight the pressing need to better understand the biodiversity conservation implications of land use change in Sub-Saharan Africa. Land use change alters natural wildlife habitats with fundamental consequences for biodiversity. Consequently, species richness and diversity typically decline as land use changes from natural to disturbed. We assess how richness and diversity of avian species, grouped into feeding guilds, responded to land use changes, primarily expansion of settlements and cultivation at three sites in the Lake Victoria Basin in western Kenya, following tsetse control interventions. Each site consisted of a matched pair of spatially adjacent natural/semi-natural and settled/cultivated landscapes. Significant changes occurred in bird species richness and diversity in the disturbed relative to the natural landscape. Disturbed areas had fewer guilds and all guilds in disturbed areas also occurred in natural areas. Guilds had significantly more species in natural than in disturbed areas. The insectivore/granivore and insectivore/wax feeder guilds occurred only in natural areas. Whilst species diversity was far lower, a few species of estrildid finches were more common in the disturbed landscapes and were often observed on the scrubby edges of modified habitats. In contrast, the natural and less disturbed wooded areas had relatively fewer estrildid species and were completely devoid of several other species. In aggregate, land use changes significantly reduced bird species richness and diversity on the disturbed landscapes regardless of their breeding range size or foraging style (migratory or non-migratory) and posed greater risks to non-migratory species. Accordingly, land use planning should integrate conservation principles that preserve salient habitat qualities required by different bird species, such as adequate patch size and habitat connectivity, conserve viable bird populations and restore degraded habitats to alleviate adverse impacts of land use change on avian species richness and diversity.
Breeding progress of nitrogen use efficiency of cereal crops, winter oilseed rape and peas in long-term variety trials
(2024) Laidig, Friedrich; Feike, T.; Lichthardt, C.; Schierholt, A.; Piepho, Hans-Peter
Breeding and registration of improved varieties with high yield, processing quality, disease resistance and nitrogen use efficiency (NUE) are of utmost importance for sustainable crop production to minimize adverse environmental impact and contribute to food security. Based on long-term variety trials of cereals, winter oilseed rape and grain peas tested across a wide range of environmental conditions in Germany, we quantified long-term breeding progress for NUE and related traits. We estimated the genotypic, environmental and genotype-by-environment interaction variation and correlation between traits and derived heritability coefficients. Nitrogen fertilizer application was considerably reduced between 1995 and 2021 in the range of 5.4% for winter wheat and 28.9% for spring wheat while for spring barley it was increased by 20.9%. Despite the apparent nitrogen reduction for most crops, grain yield (GYLD) and nitrogen accumulation in grain (NYLD) was increased or did not significantly decrease. NUE for GYLD increased significantly for all crops between 12.8% and 35.2% and for NYLD between 8% and 20.7%. We further showed that the genotypic rank of varieties for GYLD and NYLD was about equivalent to the genotypic rank of the corresponding traits of NUE, if all varieties in a trial were treated with the same nitrogen rate. Heritability of nitrogen yield was about the same as that of grain yield, suggesting that nitrogen yield should be considered as an additional criterion for variety testing to increase NUE and reduce negative environmental impact.
Comparative ungulate diversity and biomass change with human use and drought: implications for community stability and protected area prioritization in African savannas
(2025) Bartzke, Gundula S.; Ogutu, Joseph O.; Piepho, Hans‐Peter; Bedelian, Claire; Rainy, Michael E.; Kruska, Russel L.; Worden, Jeffrey S.; Kimani, Kamau; McCartney, Michael J.; Ng'ang'a, Leah; Kinoti, Jeniffer; Njuguna, Evanson C.; Wilson, Cathleen J.; Lamprey, Richard; Hobbs, Nicholas Thompson; Reid, Robin S.
Drought and human use may alter ungulate diversity and biomass in contrasting ways. In African savannas, resource‐dependent grazers such as wildebeest (Connochaetes taurinus) and zebra (Equus quagga) may decline or disperse as resources decline, opening space for more drought‐tolerant species such as gazelles (Eudorcas and Nanger) and impala (Aepyceros melampus). This shift can increase species richness, evenness, and overall ungulate diversity. Although higher diversity may stabilize ungulate communities, it may be associated with lower biomass (the total body mass of all individuals in a community), which in turn affects vegetation structure and composition, nutrient cycling, energy flows, and other organisms in savannas. While ungulate biomass often declines during drought or in areas of intense human use, the effects on diversity changes under low‐to‐moderate human use remain less clear. Our fine‐scale censuses in the Maasai Mara National Reserve and adjacent pastoral lands in Kenya showed that ungulate biomass declined more than diversity in the 1999 drought year. In the normal rainfall year of 2002, diversity peaked along the reserve boundary, but species richness leveled off in the drought year. Biomass peaked in the reserve in both census years, and migratory ungulates moved further into the reserve in the drought year, where diversity declined. These findings suggest that core protected areas are crucial for maintaining ungulate biomass, while transition zones from protected and pastoral lands support higher diversity unless drought reduces species richness.
Description and prediction of copper contents in soils using different modeling approaches - results of long‐term monitoring of soils of northern Germany
(2022) Ludwig, Bernard; Klüver, Karen; Filipinski, Marek; Greenberg, Isabel; Piepho, Hans‐Peter; Cordsen, Eckhard
Background: Different regression approaches may be useful to predict dynamics of copper (Cu), an essential element for plants and microorganisms that becomes toxic at increased contents, in soils. Aim: Our objective was to explore the usefulness of mixed-effects modeling and rule-based models for a description and prediction of Cu contents in aqua regia (CuAR) in surface soils using site, pH, soil organic carbon (SOC), and the cation exchange capacity (CEC) as predictors. Methods: Three sites in northern Germany were intensively monitored with respect to CuAR and SOC contents, pH, and CEC. Data analysis consisted of calibrations using the entire data set and of calibration/validation approaches with and without spiking. Results: There was no consistent temporal trend, so data could be combined for the subsequent regressions. Calibration using the entire data set and calibration/validation after random splitting (i.e., pseudo-independent validation) were successful for mixed-effects and cubist models, with Spearman's rank correlation coefficients rs ranging from 0.83 to 0.91 and low root mean squared errors (RMSEs). Both algorithms included SOC, CEC, and pH as essential predictors, whereas site was important only in the mixed-effects models. Three-fold partitioning of the data according to site to create independent validations was again successful for the respective calibrations, but validation results were variable, with rs ranging from 0.04 to 0.76 and generally high RMSEs. Spiking the calibration samples resulted in generally marked improvements of the validations, with rs ranging from 0.45 to 0.67 and lower RMSEs. Conclusions: Overall, the information provided by SOC, pH, and CEC is beneficial for predicting CuAR contents in a closed population of sites using either mixed-effects or cubist models. However, for a prediction of CuAR dynamics at new sites in the region, spiking is required.
Impact of different growing substrates on growth, yield and cannabinoid content of two Cannabis sativa L. genotypes in a pot culture
(2020) Burgel, Lisa; Hartung, Jens; Graeff-Hönninger, Simone
The impacts of different growing substrate compositions, consisting of peat (PM), peat substituted with 30% green fibre (G30) and coco coir fibre (CC) growth media, were investigated in regard to the plant height, biomass and floral yield, biomass nitrogen (N) content, root growth, and cannabidiol content (CBD/A) of two phytocannabinoid-rich cannabis genotypes in an indoor pot cultivation system. Genotypes and substrate treatment combinations were randomly allocated to 36 plants according to a Latin square design. The results showed a higher total plant height for PM (39.96 cm), followed by G30 (35.28 cm), and the lowest in CC (31.54 cm). The N content of leaves indicated the highest values for plants grown in G30 (52.24 g kg DW−1), followed by PM (46.75 g kg DW−1) and a significantly lower content for CC (37.00 g kg DW−1). Root length density (RLD) increased by 40% (PM) and 50% (G30), compared to CC treatments, with no significant differences in root dry weight. Both genotypes, Kanada (KAN) and 0.2x, reacted in a genotype-specific manner. KAN indicated a reduced floral yield of plants grown in G30 (4.94 g plant−1) and CC (3.84 g plant−1) compared to PM (8.56 g plant−1). 0.2x indicated stable high floral yields of 9.19 g plant−1 (G30) to 7.90 g plant−1 (CC). Leaf DW increased in PM (5.78 g plant−1) and G30 (5.66 g plant−1) compared to CC (3.30 g plant−1), while CBD/A content remained constant. Due to a higher biomass yield, the CBD/A yield of flowers (549.66 mg plant−1) and leaves (224.16 mg plant−1) revealed 0.2x as an interesting genotype for indoor pot cultivation in a peat-based substrate substituted with 30% green fibres. Overall, the demand for organic green fibres to partly replace fractionated peat showed a genotype-specific option for a homogeneous plant development, with comparable high biomass yields and stable cannabinoid contents compared to a peat containing standard substrate.
Impact of soil improvers on soil health: A data mining approach to support sustainable agriculture across the EU
(2025) Nolfi, Lorenzo; Bindo, Arianna; Di Gregorio, Luciana; Costanzo, Manuela; Caldara, Marina; Tabacchioni, Silvia; Visca, Andrea; Salo, Tapio; Bauerle, Andrea; Hansen, Veronika; Bernini, Roberta; Varese, Giovanna Cristina; Manikas, Ioannis; Marmiroli, Nelson; Palojärvi, Ansa; Bevivino, Annamaria
Soil health is crucial for the sustainability of agricultural practices and ecosystem resilience. Using a data mining approach, this study aims to explore emerging themes related to the impact of soil improvers on soil health by analyzing results from various EU-funded agricultural projects, with the final goal of identifying the key factors driving the effectiveness of soil amendments. By integrating data mining and text analysis, the study extracts, aggregates, and visualizes insights, providing a comprehensive overview of innovative strategies to enhance soil fertility and promote ecological balance. This integrated analytical framework offers a nuanced understanding of the conceptual landscape surrounding soil health in EU projects, highlighting the multifaceted roles of organic amendments and microbial solutions. Our findings underscore the critical link between organic amendments and soil health, highlighting their potential as strategic tools for achieving more sustainable agricultural systems. These findings provide a basis for refining soil management strategies in agriculture and support the development of evidence-based policies aimed at improving soil health and fostering ecological balance across Europe.
Improving cover crop mixtures to increase soil carbon inputs and weed suppression as a tool to promote yield potential
(2024) Groß, Jonas; Müller, Torsten
Arable cropping systems are facing challenges imposed by climate change and are, at the same time, a tool to mitigate climate change. Soils are essential in securing yield potential and acting as a carbon sink. Recognizing small-scale site-specific differences in crop management and integrating cover crops, which provide ecosystem services such as carbon sequestration and weed suppression, are two approaches to climate-smart agriculture. To investigate site-specific soil heterogeneity, soil properties were analyzed in a field trial, measuring at three soil depths in 42 plots to determine their influence on yield measures. Soil organic carbon, silt, and clay contents in both topsoil and subsoil explained 45-46% of the variability in grain yield. Additionally, a positive correlation was found between increasing clay content in the topsoil and grain yield and tiller density. A higher clay content in the subsoil resulted in a decrease in grain yield. Soil organic carbon was identified as a soil property that positively influences yield and yield formation at any soil depth through multiple regressions and cluster analysis. Soil organic carbon is a critical soil measure that can significantly improve yield potential and can be manipulated by crop management practices like cover cropping. In a second field experiment, the impacts of increasing plant diversity of cover crop mixtures on rhizosphere carbon input and microbial utilization were investigated. A comparison was made between Mustard (Sinapis alba L.) planted as a sole crop and diversified cover crop mixtures of four (Mix4) or twelve (Mix12) species. A 13C-pulse labeling field experiment traced C transfer from shoots to roots to the soil microbial community. Mix 4 doubled the net CO2-C removal from the atmosphere, while Mix 12 more than tripled it, indicating that plant diversity positively impacts carbon cycling. This is reflected in higher atmospheric C uptake, higher transport rates to the rhizosphere, higher microbial incorporation, and longer residence time in the soil environment, improving the efficiency of C cycling in cropping systems. Root C-transfer could be identified as a fast pathway for C to reach soil C-compartments, but a substantial share of atmospheric C-catch comes from shoot biomass. In a third field experiment, the influence of species combination on shoot biomass formation was systematically assessed by investigating species interactions in dual cover crop mixtures and their competitiveness to suppress weeds before winter under different growing conditions. The shoot biomass share of a cover crop species in a dual-species mixture was found to be directly linked to its shoot biomass in a pure stand. Mustard and phacelia had similar effects on the shoot biomass production of the second species added to the mixture. Cruciferous species were more competitive against weeds than other cover crop species and could suppress weeds even when mixed with a less competitive partner. Weed suppression in mixtures with phacelia depended on the second component. Our results indicate that dual mixtures containing one competitive species reduce weed shoot biomass before winter, comparable to competitive pure stands. The research in this thesis shows that C content in the soil plays a crucial role in yield formation in arable cropping systems in Germany. Finally, the study has demonstrated that implementing cover crop mixtures can enhance soil C input and represent a valuable method for preserving yield potential. It was also shown that an intelligent combination of cover crop species can determine successful development and weed suppression.
The role of digital technologies to support sustainability management in agriculture
(2025) Weber, Rolf; Lewandowski, Iris
Agriculture causes many environmental problems in the production of food. In addition to the emissions that the agricultural sector emits in the upstream and downstream value chains, the use of plant protection products to increase yields also contributes to the decline in biodiversity. Consumer demands for more sustainable food production are increasing and stricter regulations are also being implemented politically to increase sustainability in European and German agriculture. To achieve this goal, many different assessment tools have been developed to measure and evaluate sustainability in agriculture. In addition to its role in the respective tools, digitization is also becoming increasingly important in food production. The possibilities of digital technologies in agriculture are multifaceted and can help to support farmers in managing their farms. Furthermore, digitization will also have an important impact on sustainability management. Digitization can help to increase the output:input ratio of farm inputs. Improving the efficiency of resource use has an impact on sustainability. However, tools for assessing sustainability in agriculture cannot show whether the use of digital technologies creates synergies or trade-offs. The sustainability tools also have limitations when it comes to assessing biodiversity, as the assessment takes place retrospectively on the one hand and across farms on the other. An algorithm that supports farmers in the field-specific biodiversity assessment before the cultivation season is still missing. Whether farmers are willing to accept the use of digital technologies to support decision-making has not yet been researched. Without the willingness of farmers to invest in digital technologies, the associated efficiency gains will remain unused and thus slow down the development towards a more sustainable agriculture. The aim of this work is to show how sustainability management in agriculture can be improved in food production with the support of digital technologies. In the study, field trials on site-specific fertilization were carried out over a period of four years on three different farms in a case study. Using the example of site-specific fertilization as a digital technology, the on-farm-research trials show which trade-offs and synergies occur between ecological and economic sustainability indicators in the digitization of agriculture in arable farming. Site-specific fertilization has led to an increase in yields, regardless of the size of the farm. This results in lower emissions per unit of product produced. In terms of economic benefits, the results show that farm size is crucial for the profitability of site-specific fertilization. The smaller the size of the farm, the higher the costs per unit associated with the technology. Whether synergies or trade-offs occur between ecological and economic sustainability indicators in site-specific fertilization has to be calculated manually so far, as the sustainability assessment tools do not provide this information. In the second study, an algorithm was developed that assesses the biodiversity potential in an indicator-based and prospective manner. To this end, agricultural management parameters (on-crop) and landscape parameters (off-crop) were first derived from the literature and then discussed in expert interviews. In these interviews, points were awarded for the on-crop and off-crop parameters and parameters influencing biodiversity in particular were weighted twice. The algorithm developed enables the biodiversity potential to be assessed on a field-specific basis. This allows farmers to determine which biodiversity potential is achieved at the cultivation planning stage. In addition, the algorithm can show farmers scenarios on how to optimize biodiversity performance. The third study addresses the social acceptance of digital technologies among farmers. The first and second study showed how the use of digital technologies can support farmers in their management. Therefore, the third research question investigated whether farmers use them at all. A qualitative Delphi study with experts was conducted to find out whether farmers accept and use digital technologies and how they affect the social dimension of sustainability. In most questions, the experts were unsure about farmers' acceptance of digital technologies and the general impact of digitization on farm life. The experts were concerned about data security, dependence on individual providers and the risk of smaller farmers not digitizing and thus being left behind in the digitization process because the costs of the technology are too high. Digital technologies can support the farmer's management on the one hand and contribute to a standardized sustainability assessment by automatically evaluating existing data on the other. However, this requires better interoperability of different software programs so that all data generated on the farm can be collected and evaluated centrally. This can enable the automation of the sustainability assessment and the transparency of sustainability performance for the downstream value chain. However, dealing with trade-offs within the sustainability dimensions when using digital technologies on the one hand, and the risk that farmers will not digitize due to a lack of economic viability on the other, hinder the digitization process.
Root foraging strategy improves the adaptability of tea plants (Camellia sinensis L.) to soil potassium heterogeneity
(2022) Ruan, Li; Cheng, Hao; Ludewig, Uwe; Li, Jianwu; Chang, Scott X.
Root foraging enables plants to obtain more soil nutrients in a constantly changing nutrient environment. Little is known about the adaptation mechanism of adventitious roots of plants dominated by asexual reproduction (such as tea plants) to soil potassium heterogeneity. We investigated root foraging strategies for K by two tea plants (low-K tolerant genotype “1511” and low-K intolerant genotype “1601”) using a multi-layer split-root system. Root exudates, root architecture and transcriptional responses to K heterogeneity were analyzed by HPLC, WinRHIZO and RNA-seq. With the higher leaf K concentrations and K biological utilization indexes, “1511” acclimated to K heterogeneity better than “1601”. For “1511”, maximum total root length and fine root length proportion appeared on the K-enriched side; the solubilization of soil K reached the maximum on the low-K side, which was consistent with the amount of organic acids released through root exudation. The cellulose decomposition genes that were abundant on the K-enriched side may have promoted root proliferation for “1511”. This did not happen in “1601”. The low-K tolerant tea genotype “1511” was better at acclimating to K heterogeneity, which was due to a smart root foraging strategy: more roots (especially fine roots) were developed in the K-enriched side; more organic acids were secreted in the low-K side to activate soil K and the root proliferation in the K-enriched side might be due to cellulose decomposition. The present research provides a practical basis for a better understanding of the adaptation strategies of clonal woody plants to soil nutrient availability.
Spotlight on agroecological cropping practices to improve the resilience of farming systems: a qualitative review of meta-analytic studies
(2025) von Cossel, Moritz; Scordia, Danilo; Altieri, Miguel; Gresta, Fabio
The capacity of agriculture to withstand or recover from increasing stresses (i.e., resilience) will be continuously challenged by extreme climate change events in the coming decades, altering the growing conditions for crop species. By prioritizing natural processes, agroecology seeks to foster climate change adaptation, boost resilience, and contribute to a low-emission agricultural system. Nineteen different agroecological practices using resilience-related terms and “meta-analysis”, within the subject areas ‘Agriculture and Biological Science’ and ‘Environmental Science’ were addressed, and 34 meta-analyses were reviewed to summarize the state-of-the-art agroecological adaptative strategies applied globally, and the current knowledge gaps on the role of agroecological practices in improving farming system resilience. Two main agroecological strategies stand out: i) crop diversification and ii) ecological soil management. The most frequent diversification practices included agroforestry, intercropping, cover cropping, crop rotation, mixed cropping, mixed farming, and the use of local varieties. Soil management practices included green manure, no-till farming, mulching, and the addition of organic matter. The analyzed studies highlight the complex interplay among soil, plant, climate, management, and socio-economic contexts within the selected agroecological practices. The results varied—positive, null, or negative—depending largely on site-specific factors. Developing and understanding more complex systems in a holistic approach, that integrates plants and animals across multiple trophic levels (feeding relationships, nutrient cycling, and aligning with the principles of a circular economy) is essential. More research is, therefore, needed to understand the interactions between crop diversity and soil management, their impacts on resilience, and how to translate research into practical strategies that farmers can implement effectively.
Status quo of fertilization strategies and nutrient farm gate budgets on stockless organic vegetable farms in Germany
(2024) Stein, Sophie; Hartung, Jens; Zikeli, Sabine; Möller, Kurt; Reents, Hans Jürgen
Fertilizer management in stockless organic vegetable production is strongly affected by external nutrient purchases due to the high nitrogen (N) and potassium (K) requirements of vegetables. However, the database on nutrient flows and budgets in organic vegetable farming in Europe is very limited. Therefore, a survey based on semi-structured interviews was carried out comprising 12 organic horticultural farms in Germany. The results show that three different main fertilizer categories are used as inputs in different ratios by the inventoried farms: (1) base fertilizers (e.g., composts, solid farmyard manures), (2) commercial organic N fertilizers (e.g., keratins or plant products from food production or fermentation processes), and (3) commercial mineral fertilizers (e.g., potassium sulfate), all of which are approved for organic production. Ninety percent of the total nutrient inputs to the farms came from these fertilizers and biological N2 fixation, with the remaining 10% coming from other inputs, such as seeds or growing media. The estimated yearly average total farm budgets were nearly balanced across all farms with moderate surpluses (67.5 kg N ha−1, 2.06 kg P ha−1, and 0.26 kg K ha−1). However, large imbalances were found for most of the individual farms. These imbalances indicate the risk of nutrient accumulation or nutrient depletion in the soil, depending on the fertilization strategy and productivity of the farm. More specifically, increasing N share from base fertilizers led to increased P and K budgets, while strategies based on the use of large amounts of keratins led to the opposite—K and P depletion. We concluded that balanced nutrient management in organic vegetable production systems requires a thorough calculation and should combine the use of base fertilizers, commercial fertilizers with low P content, and increased N supply via BNF.
Testing agronomic treatments to improve the establishment of novel miscanthus hybrids on marginal land
(2025) Lewin, Eva; Clifton‐Brown, John; Jensen, Elaine; Lewandowski, Iris; Krzyżak, Jacek; Pogrzeba, Marta; Hartung, Jens; Wolfmüller, Cedric; Kiesel, Andreas; Fujii, Yoshiharu
Miscanthus is considered a promising candidate for the cultivation of marginal land. This land poses unique challenges, and experiments have shown that the “establishment phase” is of paramount importance to the long-term yield performance of miscanthus. This experiment analyzes novel miscanthus hybrids and how their establishment on marginal land can be improved through agronomic interventions. Experiments took place at two sites in Germany: at Ihinger Hof, with a very shallow soil profile and high stone content, and at Reichwalde, where the soil was repurposed river sediment with low organic matter, high stone content, and a compacted lower horizon. These marginal conditions functioned as test cases for the improvement of miscanthus establishment agronomy. Four hybrids ( Miscanthus x giganteus , Gnt10, Gnt43, and Syn55) and agronomic treatments such as plastic mulch film, miscanthus mulch, inoculation with mycorrhizal fungi, and fertilization were tested in two years at both sites in 2021 and 2022. Specific weather conditions and the timing of planting were strong determinants of establishment success and no single treatment combination was found that consistently increased the establishment success. Plastic mulch films were found to hinder rather than help establishment in both these locations. Chipped miscanthus mulch caused nitrogen immobilization and stunted plant growth. At Ihinger Hof the novel seed-based miscanthus hybrid Gnt43 produced twice the biomass of other hybrids (7 t ha −1 ) in the first growing season. Gnt10 yielded well in 2021 and showed impressive tolerance to water stress in the summer of 2022. No treatment combination was found that consistently increased the establishment success of miscanthus hybrids across sites and years. Novel genotypes consistently outperformed the standard commercial miscanthus hybrid Miscanthus x giganteus . Gnt10 may be a promising candidate for the cultivation of water-stress-prone marginal lands, due to its isohydric behavior and high yield potential.
To move or not to move—factors influencing small-scale herder and livestock movements in the Dzungarian Gobi, Mongolia
(2023) Michler, Lena M.; Kaczensky, Petra; Oyunsaikhan, Ganbaatar; Bartzke, Gundula S.; Devineau, Olivier; Treydte, Anna C.
In Mongolia, where nomadic pastoralism is still practiced by around one-third of the population, increasing livestock numbers, socio-economic constraints and climate change raise concerns over rangeland health. Little empirical evidence explains what triggers camp moves of pastoralists in the Dzungarian Gobi in Mongolia, which factors influence grazing mobility around camps, and how altitudinal migration benefits small livestock. We combined GPS tracking data of 19 small livestock herds monitored from September 2018 to April 2020 with remotely sensed climate and environmental data. We used general linear-mixed models to analyse variables influencing camp use duration and daily mobility patterns. To understand the importance of the altitudinal migration, we compared climatic conditions along the elevation gradient and looked at seasonal body weight changes of small livestock. We found that available plant biomass and season best explained camp use duration. Daily walking distance and maximum distance from camp increased with camp use duration. Pasture time increased with increasing biomass and rising temperatures. We conclude that herders in the Dzungarian Gobi have optimized pasture use by reacting to changes in biomass availability at landscape and local scale, and by embracing altitudinal migration. Flexibility in grazing mobility seems to have enabled local herder communities to practise sustainable pasture use. Maintaining this mobility will most likely be the best strategy to deal with environmental change under the current climate change scenarios.
Yield stability and weed dry matter in response to field-scale soil variability in pea-oat intercropping
(2025) Munz, Sebastian; Zachmann, Julian; Chongtham, Iman Raj; Dhamala, Nawa Raj; Hartung, Jens; Jensen, Erik Steen; Carlsson, Georg
Background and aims: Intercropping of grain legumes and cereals in European agriculture can provide benefits, such as an increase in yields, yield stability and weed suppression. Interactions between crops in intercropping may depend on spatial heterogeneity in soil conditions, which are present on farmers’ fields. Understanding the effect of within-field variation in soil conditions on interspecific interactions might increase the benefits of intercropping by within-field adjustment of the agronomic management. Methods: Crop performance and weed dry matter were assessed together with several soil properties in grids within three large field experiments at two sites (Germany and Sweden) and during two years. Each experiment was comprised of several strips sown either with the two sole crops oat ( Avena sativa L.) and field pea ( Pisum sativum L.) or an oat-pea intercrop. Results: The response of crop performance to within-field variability in soil conditions was mostly species-specific. Yield stability of intercropping was consistently higher compared with pea, but not compared to oat. The highest land equivalent ratio was found for an additive intercropping design under a higher water availability. In this experiment, yield stability of both intercropped pea and oat were lower, which might be expected as a result of within-field variation in interspecific interactions. Intercropping reduced weed dry matter compared to pea, for which one experiment indicated an increase in weed dry matter with nutrient availability. Conclusion: The experimental design and the developed statistical analysis can contribute to further research about spatial variations in interspecific interactions in intercropping, which will improve the understanding of plant-plant and plant-soil interactions.

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