Wasser und Entwicklung

Drought as a slow-onset phenomenon inflicts important losses to agriculture where the degree of vulnerabilitydepends not only on physical variables such as precipitation and temperature, but also on societal preparedness.While the scopes of physical and social vulnerability are very different in nature, studies distinguishing these twoaspects have been lacking. In this study we address the physical and social aspects of drought vulnerability ofmaize (CDVI_phy and CDVI_soc) in Sub-Saharan Africa (SSA). To quantify vulnerability, we applied a probabilisticframework combining a Drought Exposure Index (DEI) with a physical or social Crop Failure Index, CFI_phy orCFI_soc, respectively. DEI was derived from the exceedance probability of precipitation. Maize yields, simulatedusing the Environmental Policy Integrated Climate (EPIC) model, were used to build CFI_phy, whereas the residualof simulated and FAO recorded yields were used to construct CFI_soc. The results showed that southern andpartially central Africa are more vulnerable to physical drought as compared to other regions. Central andwestern Africa, however, are socially highly vulnerable. Comparison of CDVI_phy and CDVI_soc revealed that societalfactors cause more vulnerability than physical variables in almost all SSA countries except Nigeria andSouth Africa. We conclude that quantification of both drought vulnerabilities help a better characterization ofdroughts and identify regions where more investments in drought preparedness are required.

The need for taking a comprehensive perspective when selecting sanitation technologies in developing contextshas been increasingly discussed. Process guides, which are planning documents describing steps decision-makersneed to take, represent one possible contribution to attain comprehensive decisions. An interview study with sanitationexperts was carried out to understand the importance and real use of such planning documents for theselection of urban sanitation technologies in developing countries, as well as to understand the relevance andactual consideration of decision elements and to identify recommendations for taking them into account. Althoughprocess guides appear to be helpful to guide planning processes, their use does not seem to be common practice. Itis actually doubtful that the sector is currently able to make better use of those documents in the form that theyexist today. Furthermore, the importance of a comprehensive approach is generally recognised, but relevantdecision elements were said to be often neglected. Finally, results from the interview analysis also emphasisedthe need for a conducive policy environment, namely by developing appropriate institutional and legal frameworks,and by incentivising planners and decision-makers to further adapt to comprehensive decision-makingpractices that effectively improve the sanitation situation in developing countries.