The trials for dry-land spring wheat cultivation under film marginalized covering, film-marginalized covering with chopped stalks and just chopped stalks covering were conducted in Xiji county in Ningxia in 2002. The results showed that all the covering techniques had significant water-saving effects, especially for film marginalized covering with chopped stalks. The covering techniques not only improve soil physical and chemical characters, alleviate the ground temperature change and increase the utility of rainfall, but also enhance the growth vigor of individual plants and the dynamic development of plant colong, inhibit the growth of weeds, increase the content of soil organic matter, and ensure the sustainable development of soil fertility maintaining. |