Contribution of Agroforestry to Natural Resources Management, Food Security and Climate Change Mitigation: Experiences from Tabora Region, Western Tanzania

Food insecurity, natural resources degradation and climate change are among the most critical challenges facing Tanzania and indeed, the developing world today. There is decreasing agricultural productivity as a result of increasing land degradation, reduced ability of forest resources to provide goods and services due to deforestation and forest degradation. There is also growing evidence that climate change is impacting on forests and forest ecosystems and therefore livelihoods of forest dependent communities as well as national economic activities that depend on forest products and services. Agroforestry which is a land-use system where woody perennials are grown in association with crops, pastures or livestock can support growth of more food and biomass for fuel while sustainably managing agricultural landscapes for the critical ecosystem services they provide. Agroforestry can serve as a means of curbing greenhouse gas emissions by slowing forest conversion to farmland and sequestering more carbon in trees on farms. Different agroforestry technologies have been tested by agricultural Research Institutes and Universities in Tanzania in collaboration with International Research Organizations including the World Agroforestry Centre. These technologies include; use of nitrogen fixing trees to contribute to increased crop yields, food security and rural incomes, Agroforestry based rotational woodlots to supply fuelwood, charcoal and livestock fodder requirements and to generate substantial income and Agroforestry based farming systems to contribute to use of restoration of degraded lands, increase carbon sequestration and thus contribute to climate mitigation. Research has for example, shown that Sesbania sesban and Gliricidia sepium can increase maize yield by 1.5t/ha and 1.0t/ha respectively when compared to no fertilizer treatment. Studies on thornless Australian acacia trees showed that Acacia crassicarpa grown on acid sandy soils produced as much as 24 to 77 tons of woodper hectare within four to five years. A maize crop grown after cutting down this tree fallow yielded as much as 29 to 113 per cent more maize than that grown on a nearby natural fallow. This paper discusses the contributions of these agro-forestry technologies towards increasing food production, improving farmers’ livelihoods as well as mitigation of climate change in Tanzania and suggests strategies for scaling up.