Types of Research
In many countries in Sub-Saharan Africa and South Asia smallholder farmers are among the most vulnerable to climatic changes, and the observed shocks and stresses associated with these changes impact agricultural systems in many ways. This research brief offers findings on observed or measured changes in precipitation, temperature or both, on five biophysical pathways and systems including variable or changing growing seasons, extreme events, biotic stressors, plant species density, richness and range, impacts to streamflow, and impacts on crop yield. These findings are the result of a review of relevant documents cited in Kilroy (2015), references included in the IPCC draft Special Report on Food Security, and targeted searches from 2015 - present for South Asia and Sub-Saharan Africa.
Water is a critical input for significantly enhancing smallholder farmer productivity in Sub-Saharan Africa (SSA) where less than 5% of farm land is irrigated, and in India where 42% of farm land is irrigated. For many years, donors have invested in human-powered treadle pump technologies as a point of entry for smallholder farmers unable to afford motorized pumps. In spite of some successes in treadle pump promotion, however, there is a widespread perception that as soon as smallholder farmers can afford to they quickly transition to motorized diesel- powered pumps. While diesel pumps substantially ease farmers’ workload, they pollute excessively (both in terms of local air quality and greenhouse gas emissions), pump excessive amounts of water, and put farmers at the mercy of cyclical spikes in fuel prices. This brief provides an overview of state-of-the-art alternative energy pumps, including technologies available and implementation lessons learned from China, India, Africa, South America and other regions. Through a literature review, written surveys and phone interviews with water pump producers and non-governmental organizations (NGOs) we evaluate the availability, affordability, and adoption rates of alternative energy technologies in developing countries. Our findings suggest that no single alternative energy water pumping system is a “silver bullet” for rural smallholder irrigation needs. Biofuels may prove a successful short- to intermediate-term solution for farmers who already have access to diesel pumps, but other problems associated with diesel engines, including high maintenance costs and excessive water use remain even when biofuels are used. Solar systems eliminate pollution almost entirely, reduce water consumption, and eliminate the need to purchase fuels. However solar systems are typically prohibitively expensive for smallholder farmers. Wind powered pumping solutions have not proven successful to date, with high costs and irregular wind patterns (either too little or too much wind) proving substantial barriers to widespread adoption.