Intensive soil tillage and mismanagement of irrigation water and fertilizers under current agricultural practices have accelerated the pace of degradation of irrigated drylands in Central Asia. Increasing water scarcity and concerns of irrigation water quality have further raised serious doubts about the sustainability of current conventional agricultural systems. In the face of these environmental and economic challenges, there is a need to introduce new agricultural systems which improve the productivity of natural resources as well as of external inputs and help prevent soil degradation. Conservation agriculture (CA) practices such as reduced tillage, residue retention and proper crop rotations offer such solutions but research on CA in Central Asia is still in its infancy. This paper reviews various studies from the irrigated zones of Central Asia wherein efficiency of various CA practices under different cropping systems have been evaluated. These studies have shown that cultivating crops on relatively permanent raised beds with residue retention, potentially saves 12-23% irrigation water in wheat and maize. Compared with conventional agriculture practices, raised bed systems saved up to 70% of irrigation water in rice. Similarly, permanent raised beds and N management based on crop demand have improved nitrogen use efficiency in irrigated drylands of Central Asia.
Topic: conservation,agriculture,farming,water,fertilizers,efficiency,soil fertility,tillage
Geographic: Central Asia
Publication Year: 2015
Source: Drechsel, P., Heffer, P., Magen, H., Mikkelsen, R., Wichelns, D. (Eds.) Managing water and fertilizer for sustainable agricultural intensification. 242-257