Browsing by Subject "Diversifikation"

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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.
Außerlandwirtschaftliche Diversifikation im Transformationsprozess. Diversifikationsentscheidungen und -strategien ländlicher Haushalte in Slowenien und Mazedonien
(2005) Möllers, Judith; Heidhues, Franz
Non-farm rural diversification is gaining prominence in the debate on rural development since the end of the 1990s. The expansion of non-farm employment and the diversification of incomes are important policy objectives because they offer a solution to the employment and structural problems of a shrinking agricultural sector. Development policies focusing on the rural non-farm sector aim at offering employment options and reducing urban migration. They can contribute to poverty reduction, economic growth and a more equal income distribution. This research is based on a household survey including 240 randomly selected rural households in Slovenia and Macedonia. Since empirically based insights on diversification dynamics in transition countries are hardly available, the objective of this research is to contribute to filling this gap. The analysis focuses on diversification strategies and determinants of the decision-making process of rural people in regard to non-farm employment. The methodology combines an inductive and deductive approach with qualitative and quantitative components. For the statistical analysis primarily logistic regression models are applied. The results show that rural households in the research area are highly dependent of non-farm incomes. As expected the poverty risk between the two countries differs: Rural household incomes in Macedonia are less equally distributed. Decomposed Gini-coefficients based on non-farm incomes point at their positive effect on the income distribution. The analysis of diversification strategies indicates that coping strategies as well as risk-minimising strategies prevail. Accumulation strategies, which point at demand-pull dynamics and entrepreneurship, are less common. Attitudes towards agriculture seem to influence diversification decisions in particular. While attitudes towards non-farm activities are predominantly positive, they vary towards agriculture. Negative attitudes towards agriculture are wide-spread among the younger generation. In the age group from 16 to 25 years the proportion of negative attitudes is high in both countries, but the share in Macedonia with 50% is twice as high as in Slovenia. Important constraints of diversification in Macedonia are the non-farm labour market, low wages, insecurity and late wage payments. In both countries capital and credit availability are named as the most important reasons for not starting a business in the non-farm sector. The pressure to adapt income strategies is lower in Slovenia in general. When looking at individual employment strategies it becomes apparent that in both countries there is a declining trend of agricultural and combined employment while non-farm employment alone is increasing. In Slovenia the high level of diversification at the household level is stabilising while the structural problems in the agricultural sector persist. In contrast, the level of diversification in Macedonia is expected to further increase even though the willingness to give up agricultural activities altogether is significantly higher than in Slovenia. A promotion of the rural non-farm sector is an important policy objective as non-farm employment has a positive impact on rural incomes, particularly in poorer households. The effect of non-farm incomes on the income distribution is positive. This underlines the importance of the non-farm sector as an essential component of a poverty-oriented rural development policy. In the long term rural development policies should aim at overcoming the unfavourable small-scale agricultural structure which is the main cause of distress-pushed diversification ? particularly if full-time employment in the non-farm sector is not available. For this it is essential to support education and knowledge-building, and to offer expert advice. The intention should be to enhance entrepreneurship, creativity and the willingness and ability to take economic risks. Furthermore, the success of any effort to improve rural development policies depends on locally developed strategies, since the heterogeneity of the non-farm sector calls for decentralised political concepts. With these prerequisites the non-farm sector will be able to absorb labour released from agriculture, and the necessary structural adjustment of the agricultural sector can take place.
Comparative advantage of Vietnam's rice sector under different liberalisation scenarios: a policy analysis matrix (PAM) study
(2004) Nguyen, Manh Hai; Heidhues, Franz
The rapidly changing global economic environment and domestic economic reforms in Viet-nam have brought the issue of comparative advantage of the rice sector to the forefront. In recent years, Vietnam has had to compete in an increasingly competitive rice export market. This paper examines the fluctuations in the comparative advantage of Vietnamese rice production based on different scenarios of trade liberalisation and economic reform in Viet-nam. To do this, a Policy Analysis Matrix (PAM) was used in conjunction with an econo-metric model. The study involved simulation of a large number of scenarios of trade liberalisation and macroeconomic reform, using variations in a single factor and in a group of factors such as product price and input costs, i.e., the price of imported fertilisers, land, water and labour costs, etc. The empirical results show that in 1998 (the baseline scenario), the comparative advantage in rice was relatively high and that the use of domestic resources ? i.e., land, labour and water ? was efficient in economic terms. The estimated DRC elasticities in respect of the world rice price and the shadow exchange rate in 1998 showed a considerably improved com-parative advantage. The estimated DRC elasticities for land rent, the social costs of labour, the import price of fertilisers and irrigation water charges were small in absolute values indi-cating small and negative impacts on comparative advantage with a rise in these prices. The results of sensitivity analyses revealed that the comparative advantage of rice is very sensitive to changes in its export price. In addition, the exchange rate and land rent are also important determinants of the rice sector?s comparative advantage in Vietnam. Other empirical results show that Vietnam is still likely to retain its comparative advantage in rice production in the next decade; however, its comparative advantage might be seriously affected or even dis-appear entirely if Vietnam is exposed to a number of unfavourable economic conditions simultaneously. The major recommendation of this paper is that production should be diversified, with appropriate agricultural policy support, within a broader framework of macroeconomic transformation and trade liberalisation.