Interactions of water, nutrient, and mulch on sorghum water use in a Sahelian agroecosystem.

摘要

In the Sahel region of Africa, grain sorghum (Sorghum bicolor (L.) Moench) is a major human food source. Due to scarce water resources and soil infertility efficient crop water use is a key challenge for sustainable crop production. The objectives of this study were to use supplemental irrigation, nutrient, and mulch to manipulate the system energy and soil water balance in order to improve crop water use efficiency and to integrate the soil-plant-atmosphere continuum water relationships into a mechanistic model capable of predicting soil evaporation and crop transpiration. The experiment site was located in Maradi, Niger. Soil physical, chemical, and hydrological properties were characterized, and water balance components (rainfall, soil evaporation, deep drainage, and changes of soil water storage), crop growth parameters (height, leaf area index, biomass production and root distribution), and relevant climatic parameters (temperatures, humidity, wind speed, and solar radiation) measured. Mulch reduced sensible flux between soil and air 3 to 5 times and soil long wave radiation emission 100 to 200 W m