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2015): Pathways to transformational change in the face of climate impacts: an analytical framework, Climate and Development,Unprecedented impacts of climate change and climate variability in the twenty-first century are likely to require transformational social, organizational and human responses. Yet, little existing empirical work examines how decisionmakers can facilitate such responses. This paper suggests that in order to assess whether responses to climate risks and threats are transformational, it is necessary to move away from a focus only on outcomes and scale and towards the multiple dimensions of social responses and the processes through which transformational changes are realized. In so doing, the paper seeks to move the discussion on transformational change towards the processes and sustainability of adaptation interventions, and the changes they trigger. Drawing on the literature on transformational change in organizational theory and social-ecological systems, the paper first develops a framework with which to examine and assess development and adaptation interventions. The framework is then applied to eight interventions made between 2005 and 2011 in diverse socioecological settings across Africa. All interventions were underpinned by participatory action research methodologies. Our analysis shows how a focus on change agents, generalizability of field-scale adaptation mechanisms and pathways, and sustainability of outcomes, combined with attention to the scale and scope of change processes, provides information that can inform policy on the kinds of intervention that are likely to support longterm and sustainable responses to climate impacts. Although several of the cases mainly illustrate incremental adaptations, use of the analytical framework pointed towards the wider processes of systems change that might lead to transformative trajectories.

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Irrigated rice is less prone generally to phosphorus (P) deficiency than rainfed rice because redox reactions release P upon soil flooding. It is not known whether that is also true in highly weathered soils of Madagascar where the combination of high soil Fe and low P input may impede significant release of P. Soils and flag leaf samples were collected in 2010 in 38 irrigated rice and 46 rainfed rice fields belonging to private farmers. A critical flag leaf P content was derived from a P‐dosed pot trial study with three soils, and the results suggested 2.4 g P/kg as the critical value. Average flag leaf P was significantly larger in irrigated than in rainfed rice (2.2 compared with 1.7 g P/kg), and flag leaf P was below the critical value in 76% of irrigated rice fields while this fraction was 100% in rainfed rice. Nitrogen and K deficiencies were less prevalent. Flag leaf P increased with increasing soil pH and soil pH explained partially differences in leaf P between irrigated and rainfed rice. Flag leaf P was unrelated to soil organic matter, but increased with oxalate‐extractable soil P (Po). Multiple regression analysis revealed greater leaf P at equal soil Po and equal pH in irrigated compared with rainfed rice. Grain yield estimates (1‐m2 squares) increased with flag leaf P but not with leaf N and K. In a regression model, about 42 % of the yield variance was explained with soil Po and a rice‐growing system. The survey suggests that P is the main limiting nutrient for rice, and that soil P bioavailability is larger for irrigated than for rainfed rice in weathered soils of Madagascar.

A vast upland area in Madagascar remains uncultivated because of erratic rainfall and because of the low fertility of the soils that are highly weathered and depleted in available phosphorus (P). This study was set up to identify to what extent farmyard manure (FYM) can overcome P deficiency and increase the use efficiency of mineral P (TSP). Rainfed rice was grown with soybean in rotation (two fields) in three subsequent seasons with factorial supplies of FYM and TSP (both applied in planting hole) with blanket N&K doses. The low and unresponsive rice grain yields (<2 Mg ha -1 ) in the initial year were contrasted with large treatment responses cumulating in a grain yield of 5.8 Mg ha -1 in year 3 at highest rates, 3.6-fold above the no P and no FYM control with N&K and 11-fold above the absolute control. The above ground P uptake responded to total P application (TSP and FYM derived) and its slope significantly increased with FYM application. The fertilizer (TSP) P use efficiency in the above ground biomass, was 14% for the zero FYM dose increasing to 22% for the highest FYM dose of 10 Mg ha -1 at year 3 of study. The FYM benefits were likely unrelated to nutritional factors as revealed from tissue analyses and it is speculated that FYM alleviates moisture stress or Al toxicity. Dosing FYM only with no TSP did not alleviate P deficiency. This study illustrates the agronomic potential of the uncultivated area provided that the soil nutrients are capitalized.