What are the characteristics of the main climate in the northwest region, the main use of what irrigation water conservancy projects

The main type of climate in Northwest China is the temperate continental climate, in Qinghai, Xinjiang, Gansu and other areas belonging to or near the Tibetan Plateau climate belongs to the plateau climate

The **** with the characteristics of the climate is arid and precipitation is scarce, cold winter and summer heat and the annual temperature difference and the daily temperature difference is very large

According to the Northwest China's natural characteristics and the development of water-saving agriculture for many years of practice, the water saving measures are usually adopted Measures are:

a. Reduce water loss, irrigation canal system renovation. The main approach is to promote channel lining and low-pressure pipeline water transfer technology, channel seepage control project is one of the main water conservation measures in many farmland irrigation water conservation measures economically reasonable and technically feasible, but also the current farmland irrigation water conservation project transformation in the key link. Shaanxi, Gansu and other places test data show that: channel seepage control can make the canal water utilization rate increased by 20% to 40%, reduce channel leakage loss 50% to 90%. It is estimated that the effective utilization coefficient of the drainage system in Northwest China is generally below 0.4, the highest is only 0.54, such as the effective utilization coefficient of the drainage system can be increased to 0.6, water consumption down to 6000m3 / h ㎡ the following, Gansu Province alone can save about 1.5 billion m3. Shaanxi Guanzhong five irrigation channels all lined, the annual water savings of about 280 million m3, equivalent to the construction of a 6.7 million h ㎡ of irrigation, water savings benefits are very substantial. Water saving benefit is very considerable.　Pipeline irrigation technology is considered to be the most economical investment, the most effective water saving, the most convenient management of a water transfer irrigation technology, in the northern region of China has been widely popularized and applied. In view of the sparsely populated northwestern region, economic lag, farmers' culture is relatively backward and other characteristics, should vigorously promote the water-saving technology.

b. Improve the efficiency of field water use, the implementation of advanced ground water-saving irrigation technology. Northwest China's current agricultural water use, on the one hand, the shortage of water resources, on the other hand, the waste of water is serious, farmland irrigation water quota, except for Shaanxi, are higher than the national average. The region's average water use index for farmland irrigation is 2.4 times that of North China, 1.6 times that of the whole country, of which Ningxia is 3.3 times that of the whole country, ranking first in the country, and the grain output per m3 of water is only 0.5kg, only 1/2 of the national average, and there is a great potential for water conservation. Irrigation in Northwest China is mainly based on surface irrigation, and the water-saving irrigation methods used in surface irrigation include: small-border irrigation in Shaanxi Luohui canal irrigation area, which saves 25% to 28.5% of water compared with the original surface irrigation method; and long-border sectional irrigation in Shaanxi Baoji Gorge and Fengjiashan irrigation area, which saves 40% to 60% of water compared with the traditional long-border irrigation. Xinjiang's membrane irrigation and small-border furrow irrigation, membrane irrigation water consumption from 4500m3 / h ㎡ reduced to 3375m3 / h ㎡, water savings of 25%; small-border furrow irrigation average net irrigation quota of 3900m3 / h ㎡, water savings of 13%. As of 1998, the irrigated area using these two irrigation methods has accounted for 65% of the effective irrigated area in the whole territory. At present, these advanced ground irrigation technology has been popularized and applied in Northwest China, especially the membrane irrigation technology created in Xinjiang, which has been widely adopted in the northern part of China due to its remarkable effect of water saving and yield increase.

c. Full storage and rational use of local water resources, the development of local irrigation. Northwest precipitation is scarce, but precipitation time is more concentrated, in order not to produce a large amount of soil erosion, make full use of rainfall runoff resources, the development of the Loess Plateau agricultural production, in recent years the implementation of the Gansu "121" rainfall irrigation project, Ningxia's kiln cellar irrigated agriculture, as well as Shaanxi's "South (Southern Shaanxi) ponds, northern (Northern Shaanxi) cellar, Guanzhong wells" water-saving irrigation projects, to solve the shortage of agricultural water resources in Northwest China, make full use of precipitation resources, the rational use of groundwater resources, additional water sources, the development of local irrigation, as well as to solve the problem of drinking water for the masses of the arid areas of Northwest China, plays an important role.

d. Vigorously promote water-saving irrigation test results. Northwest Water Conservancy Research Institute and Shaanxi Provincial Water Conservancy Department and other units, through systematic experimental research, analyze the relationship between crop yield and water demand and high-yield water conditions, put forward the research results of high-yield water-saving irrigation of the main crops in Shaanxi Guanzhong Irrigation District [3]. The study established a theoretical basis for high-yield water-saving irrigation system from the aspects of crop water demand, irrigation water-saving pathways and water-saving indexes. According to the formulation of water-saving and high-yield irrigation system program, compared with the current irrigation system to save water 1500m3 / h ㎡. The results of the Guanzhong Irrigation District by the development of high-yield piece of research on the application of seven pilot, grain yield of 1.5 million kg / h ㎡, cotton yield of up to 1500 kg / h ㎡ or more, with a significant role in saving water and increasing yields.

e. Implementation of integrated agricultural technical measures to improve water use efficiency, the development of irrigated agriculture in the northwest, not only to take water-saving irrigation methods, more need to apply certain agronomic water conservation measures, this point is more important than any region of our country is significantly important, it is to improve a water-scarce areas of limited water resources of the overall utilization of agriculture to maintain the stable development of an important significance. Northwest region in the implementation of various water-saving irrigation technology, but also on the integrated agronomic water-saving technology has carried out a lot of research. According to the natural and economic characteristics of different types of areas, the farming techniques of reasonable fertilization, water regulation by fertilizer, water storage and moisture conservation; moisture conservation by ground film and straw mulching, chemical control, reasonable adjustment and optimization of crop planting structure; selection of drought-resistant crops and water-saving varieties; in order to make full use of the irrigation water, natural precipitation, soil water and groundwater, to improve the efficiency of water use, and to achieve water-saving and high-yield, high-quality and low-consumption. The Institute of Soil and Water Conservation of the Chinese Academy of Sciences adopts calcium chloride - erythromycin combination treatment seed drought-resistant and water-saving technology, which is demonstrated in Guyuan County of Ningxia, and increases the average yield of spring wheat by 23.2%. Xinjiang used FA drought dragon drought agent, in the crop growth period applied 2 to 3 times, yield increase of 15% to 25%. Gansu, Ningxia trial planting of mulch wheat, mulch corn, yield over 6000kg / h ㎡ and 1.2 million kg / h ㎡, than the conventional cultivation of wheat and corn production were 2 to 5 times higher.