盐碱化(国外英文资料).docVIP

盐碱化(国外英文资料) The area of Chinas salt alkali land is 36.3 million hm2, and the land salinization is one of the major problems of the degradation of agricultural ecological environment. Land salinization treatment and prevention of China arid, semi-arid and semi-humid region agricultural ecosystem degradation, agricultural ecological environment protection and the future of food security has very important practical significance. Currently, the proportion of bio-fertilizer use in many countries in Europe is between 45 and 60 percent, while the United States USES 60 percent to 70 percent. But in our country, organic bio-fertilizer and the future are widely used, and the large number of farmers who use it are still fertilisers, which are seriously misaligned. The use of chemical fertilizers makes the soil more and more barren, and soil fertility falls into the potential threat of agriculture. To stop this trend, our country agricultural sector since 1995 the implementation of the plan, fertile soil requires farmland fertilizer input amounts not less than 2000 kg per acre per year, by the end of the century the existing farmland productivity yields by one level. Land salinization were due to improper human activity, cause the water soluble salts in the soil and groundwater in the body with the capillary water upward movement, under the condition of strong evaporation in the soil accumulation, so that the soil salinization, the crops can grow or affected the growth crops and cause land degradation. Soil salinization-alkalization, affects the crops on the absorption of water and nutrients, and even make plants produce physiological toxicity, especially after alkaline soil structure becomes bad, reduced the validity of the soil nutrient, make the land degradation of soil fertility, cause a harm to the sustainable development of agriculture. Saline alkali soil in China are mainly distributed in north China, northwest and northeast area in arid areas, among them the majority