According to world population ...

According to world population statistics, approximately one billion people live in semiarid regions worldwide and yet the number of people living and deriving their livelihoods from the productivity of these marginal lands is growing by the day. Semiarid areas have at least one entirely rainless month/year and the amount of rainfall ranges from 500 to1000 mm per annum in most areas. This means that conditions of water deficit, water stress, or drought are common. Agricultural researchers, policy makers and other key stakeholders that are actively involved in promoting or increasing agricultural productivity in semiarid areas all seem to agree that the solution to this challenge lies in sustainable agricultural production. This concept of sustainable agricultural production entails improved management of the available and limited resources and use of improved crop production technologies that can enhance sustainable production in semiarid areas. Improved use of the limited resources can be achieved by managing the natural resources sustainably; for example, use soil and water conservation measures to prevent land degradation (mainly through soil erosion and run off), and conserve soil fertility and improved use of the water resources through rainfall harvesting.