Linking innovations adoption with farm sustainability: Empirical evidence from rainwater harvesting and fertilizer micro-dosing in Tanzania
研究了坦桑尼亚半干旱和半湿润地区采用雨水收集和肥料微量施用对家庭环境、社会和经济可持续性的影响，发现湿润地区能提高粮食安全，而干旱地区经济可持续性反而下降。
• We evaluate rainwater harvesting (RH) and fertilizer micro-dosing (FMD) impacts. • We assess combined RH-FMD on many dimensions of sustainability in Tanzania. • Food security can increase with combined RH-FMD in households in humid regions. • No effect found on food security in dry regions but a decrease in the economic pillar. • RH-FMD should be promoted in humid rather than dry regions of East Africa. Food insecurity and poverty are of major concern for farmers and rural households in Tanzania. Innovations to increase the sustainability of households must be carefully investigated by integrating, in the analysis, the effect on crop yields with a holistic view on the overall sustainability and its components. Rainwater harvesting and fertilizer micro-dosing can increase food security, particularly in water-limited contexts, but they can also significantly increase labor requirements and the availability and use of water resources in villages and watersheds. The purpose of this study was to quantify the impacts of rainwater harvesting and fertilizer micro-dosing on environmental, social and economic sustainability of households in two regions in Tanzania – semi-arid Dodoma and semi-humid Morogoro. We selected and calculated 40 sustainability indicators for 892 households in 2013 and 2016, and we applied Difference-in-Difference Propensity Score Matching to identify relative changes in household sustainability. We show that in the dry region of Dodoma, economic sustainability increased less for adopters of the innovations in comparison to non-adopters between the years 2013 and 2016, with 6 percentage points and 11 percentage points respectively. In contrast, in the humid region, the adoption of innovations increased food security by 14 percentage points compared to 6 percentage points in the case of non-adoption. These results highlight that innovations must fit the context and should not be scaled without prior analysis of multiple impact dimensions as they may trigger significant trade-offs. By moving the focus from field to farm scale, this study contributes to providing a more rigorous assessment of the spillover effects that in-field innovations can have on the overall sustainability of households, which is a prerequisite for the advancement of sustainable intensification of agricultural production in the region.