Arnim Kuhn

Biomass-Based Value Webs: A Novel Perspective for Emerging Bioeconomies in Sub-Saharan Africa

Growing demand for increasingly diverse biomass-based products will transform African agriculture from a food-supplying to a biomass-supplying sector, including non-food agricultural produce, like feed, energy and industrial raw materials. As a result, agriculture will become the core part of a biomass-based economy, which has the potential not only to produce renewable biological resources but to convert this biomass into products for various uses. The emerging bioeconomy will intensify the interlinkages between biomass production, processing and trading. To depict these increasingly complex systems, adapted analytic approaches are needed. With the perspective of the “biomass-based value web” approach, a multi-dimensional methodology can be used to understand the interrelation between several value chains as a flexible, efficient and sustainable production, processing, trading and consumption system.

Considering salinity effects on crop yields in hydro-economic modelling - the case of a semi arid river basin in Morocco.

Agricultural production, especially date palm cultivation, is the major food and income source for people in the Drâa basin in Southern Morocco. However, the semi-arid river basin faces very low rainfalls and has suffered from a continuing drought over the last years. River water, as the principal source for irrigation, has been increasingly substituted by groundwater mining. This has led to an unsustainable downing of the groundwater table, increased salinisation problems, and has posed further constrains on the agricultural production potential. Without targeted water resources management, water available for irrigation will soon be depleted or too saline to be used for most crops. Consequently, farmers will not be able to maintain their production levels, and subsequently lose an important source of family income. The relationship between water use and agricultural production is represented using an integrated hydro-agro-economic simulation model with a spatial water distribution network of inand outflows, balances and constraints. The model results are driven by profit-maximising water use by agricultural producers which are primarily constrained by both water availability and quality. Crop yields are influenced by quantitative irrigation water application deficits and by the salinity of irrigation water. Results show considerable differences depending on whether salinity is incorporated or not. When salinity is considered, yields tend to be much lower despite increased irrigation water needs to enable a reduction of soil salinity through leaching.

Regional (dis-)integration of Russia's agro-food markets.

This paper examines the extent of interregional integration of Russian food markets from different perspectives. Though food price levels in Russia are converging after the period of hyperinflation, remote regions like the Far East seem to be on a different price path. With regard to the interregional commodity flows, it could be shown that interregional transportation of grain is unlikely to have decreased significantly, if the figures are corrected for imports and feed use. But a cross-sectional regression analysis using differences between regional production and consumption revealed that regional surpluses as well as deficits for all products tend to dimmish, which means that the Russian regions increasingly rely on their regional production and not on interregional trade.

Technology Adoption Under Variable Weather Conditions: The Case of Rain Water Harvesting in Lake Naivasha Basin, Kenya

This paper applies a parametric econometric duration model (log–logistic) to analyze the duration of adoption of rain water harvesting techniques (RWHTs) among smallholder farmers in the Lake Naivasha basin, Kenya. The study utilizes survey data from 307 farm-households who are dependent on rain-fed agriculture in a region where rainfall has historically been relatively variable. In such circumstances, RWHT helps to stabilize water supply and help farmers manage weather-related risks. The current study seeks to identify constraints to the spread of RWHTs by exploring how rainfall variability influences the timing of decisions to adopt RWHTs alongside other farm-household and spatial characteristics. Empirical results indicate that although rainfall variability is a significant determinant of time to adoption of RWHTs, farmers’ sensitivity to rainfall variability have declined over time. Instead, access to informal sources of information has gained importance in adoption of RWHT implying that adoption has become more of an endogenous process of social exchange within communities, and less driven by external natural pressure and persuasion by state agents. Other important factors were: age and education level of household head, domestic water demand, ground water abstraction and the number of previous and expected adopters in the village.