Human land use threatens global biodiversity and compromises multiple ecosystem functions critical to food production. Whether crop yield–related ecosystem services can be maintained by a few dominant species or rely on high richness remains unclear. Using a global database from 89 studies (with 1475 locations), we partition the relative importance of species richness, abundance, and dominance for pollination; biological pest control; and final yields in the context of ongoing land-use change. Pollinator and enemy richness directly supported ecosystem services in addition to and independent of abundance and dominance. Up to 50% of the negative effects of landscape simplification on ecosystem services was due to richness losses of service-providing organisms, with negative consequences for crop yields. Maintaining the biodiversity of ecosystem service providers is therefore vital to sustain the flow of key agroecosystem benefits to society.
To estimate the effects of weather conditions on welfare globally, cross-country comparisons need to rely on international poverty lines and comparable data sources at the micro-level. To this end, nationally representative household surveys can offer a useful instrument, also at the sub-national level. This study seeks to expand the existing knowledge on the determinants of poverty in Africa south of the Sahara (SSA), examining how long-term climatic conditions and year-specific weather shocks affect expenditure per capita. We take advantage of a novel and unique dataset combining consumption-based household surveys for 24 SSA countries -representative of more than half of the African population and two thirds of SSA- and geospatial information on agro-climatic conditions, market access and other spatial covariates of poverty. To our knowledge, it is the first time that a welfare-based, multidisciplinary, micro-level dataset with such wide spatial coverage has been assembled and examined. Our analysis relies on a linear and spatial model at the household- and district-level, respectively, both controlling for socio-economic, demographic, and geographic confounding factors. Results are consistent across econometric approaches, showing that living in more humid areas is positively associated with welfare, while the opposite occurs living in hotter areas, as existing literature shows. Flood shocks -defined as annual rainfall higher than one standard deviation from the 50-year average- are associated to a 35% decrease in total and food per-capita consumption and 17 percentage point increase in extreme poverty. On the other hand, extreme shortages of rain and heat shocks show an uncertain effect, even when estimates control for spatial correlation between welfare and weather conditions using the spatial error correction model. Given the heterogeneous effects of climatic events across SSA macro-regions, local-specific adaptation and mitigation strategies are suggested to help bringing households on a sustainable path.
[学术文献] Does foreign capital really matter for the host country agricultural production? Evidence from developing countries 进入全文
Review of World Economics
Despite the high flow of foreign assistance and foreign direct investment (FDI) to developing countries, the potential of agricultural production remains low and stagnant. Accordingly, it is interesting to know how each type of foreign capital (FDI and foreign aid) affects the agricultural output? And what are the most effective forms of aid that increase agricultural production? The main objective of this study is to give answers to these equations using data for 50 developing countries over the 1995–2015 period. Our results indicate, first, that the effect of FDI only (without foreign aid) has a positive and significant effect on agricultural production. Second, we found that the four forms of foreign aids [notably social-infrastructure-aid (SIA), investment aid, non-investment-aid, agriculture–forestry–fishing-aid (AFFA)] have positive and significant effects on agricultural production. Finally, when we introduced both variables in the model, we found that FDI and two types of foreign aids (SIA and AFFA) have positive and significant effects on agricultural production. In conclusion, the synergies inherent between FDI, SIA, AFFA, increase twice the agricultural production.