Soil moisture stress and infertility are major biophysical constraints which limit crop production and food security in marginalized areas. Marginal areas are mainly associated with low rainfall which is insufficient to support crops until maturity is reached. The use of insitu rainwater harvesting methods such as planting pits, tied ridges, mulching, Zai pits and half-moon can be a solution to reduce moisture stress. This alone cannot improve crop yields hence the need to use integrated nutrient management (INM) of animal manure, biofertilisers, mineral fertiliser and composts to improve soil fertility, structure and increase water retention ability. Combining rainwater harvesting with INM has the potential to mitigate effects of climate change, improve crop yields and meet food demand in marginal areas. Various nutrient sources used as INM can restore soil health, increase microbial population, nutrient mineralisation and improve soil quality. Use of biofertilisers in agriculture reduces soil toxicity, improve nutrient availability and create a conducive environment for crop growth and development. Integration of tied ridges with cattle manure and mineral fertiliser has the potential of increasing infiltration rates, reducing surface runoff and increase crop yields with 50-150% regardless of soil type. This chapter sought to come up review the effects of rainwater harvesting methods and INM on soil fertility, moisture stress and crop yields in marginalized areas.
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