Sustainable intensification & agricultural involution in Southern Africa : farming system analysis and bio-economic modelling of smallholder agriculture in the Okavango basin
This study sets out to identify optimal strategies of farm households in three study sites within the Okavango River Basin (ORB). Specifically, it assesses the role which conservation agriculture may play for the sustainable intensification of smallholder agriculture in the ORB; a main focus lies on whether or not households have sufficient resources to adopt this improved practice.By conducting an in-depth farming system analysis, this study confirms that the assumptions of the Boserup-Ruthenberg framework for the analysis of agrarian societies hold true for the research area. This means that local farming systems can be understood as belonging to a continuum of tropical smallholder farming systems which are linked by land scarcity as a main driver of change. Furthermore, the study sites in the mid- and low-river areas are affected by increasingly binding constraints to farming, mainly in regards to a pronounced seasonality in labour-demand, scarcity of arable land and erratic rainfalls. Currently, the farming systems in all three study sites are affected by degradation dynamics and likely to follow a pathway of agricultural involution (while Boserupian, or endogenous, intensification appears less likely). However, this process may create just those conditions that favour the likelihood of success of externally induced efforts towards the sustainable intensification of smallholder agriculture.Building on the farming system analysis, a bio-economic farm household model is developed. Its goal is to assess which specific combinations of farming practices (traditional practices and/or conservation agriculture) allow for the sustainable intensification of smallholder agriculture in the study sites. To achieve this goal, the model simulates i) seasonality in demand for labour and field inputs and ii) the dynamic feedback between farm-management and empirically assessed levels of soil fertility. The model regards family labour as a household s central resource, which is needed to activate the other productive resources land (via the time constrained task of land preparation) and capital (by engaging in casual labour or selling crop surpluses). Scenario analysis is applied to assess the effect of i) increasing land scarcity (a main impact of population growth on households farming strategies), ii) subsidies on input prices and iii) favourable rainfall conditions on optimal farming strategies and likelihood of endogenous intensification.Model results indicate that optimal household strategies in the study sites are determined by the degree to which households cope with seasonal peaks in labour demand and land scarcity. The more binding these constraints are for production, the more likely it is that conservation agriculture plays an important role in optimal household strategies. The less binding they are, the less willing are smallholders to adopt conservation agriculture. Furthermore, results indicate that all households have a sufficiently large labour pool to adopt conservation agriculture; however, the poorer households may be too cash-constrained to do so.Considering that increasing land scarcity and climate change will continue to drive agricultural involution and degradation dynamics in the ORB, this study argues that externally induced sustainable intensification is needed. Conservation agriculture, as currently practiced in the ORB, is one of the best available options to achieve this goal; it should be promoted via adequate pro-smallholder policies.
Verknüpfung zu Publikationen oder weiteren Datensätzen
