Study On The Effect Of The Wind And The Light To The Soil Moisture Evaporation And Moist-locking Measures

Northwest less rainfall and drought, water, loess barren, keep the water is very poor .vegetation growth difficulty, weak ecological environment. How to improve the ability of loess keep moisture arid, for the rational utilization of water resources, ensure plant growth has important fundamental significance. Based on the loess mixing, keep the water, and the particularity of the test, is devoted to the exploration can effectively enhance the soil, reasonable economy arid soil improvement of new methods.According to the characteristics of soil moisture evaporation, the use of indoor and outdoor tests and the method of combining theoretical analysis of loess properties and improved water conservation methods are more in-depth study. Mainly carried out the study of the impact of wind speed with the wall and the net, the field experiments about the impact of the soil moisture evaporation with the wall and the net, he field experiments about the impact of the soil moisture evaporation with the sand and straw mulch tests and pilot plant. Experiments show that: the wall can effectively reduce soil moisture evaporation, sand and straw mulch can greatly reduce soil moisture evaporation, for the local wind and strong solar radiation, combining the two can reduce evaporation of soil moisture. Field planting show that: using cover to reduce soil moisture evaporation, the green is completely feasible.The main contents of the thesis:Chapter 1, expounds the background and significance of the research, the research of waterborne arid loess necessity and research and development at home and abroad, summarizes and analyzes the general goal of study and solve the key problem, this paper summarizes the main research contents.Chapter 2, of Gansu province, Jing Tai county hydrological and meteorological data, the water on the investigation and analysis, soil fertility and soil conditions on Jing Tai county for large-scale soil improvement methods of the basic information and data.Chapter 3, under the impact of the main factors of soil water evaporation --speed, expand the theoretical analysis and field testing of wind speed on soil moisture evaporation .In theory, using wind speeds which measured in field combined with field simulation to check up the impact of the wall on the feasibility analysis to wind speed, field experiments used the construction of the wall and the net reduces wind speed, while using weighing method measure the soil moisture evaporation and wind range which reduced wind speed by the wall and the net. Both of them shows: reduce wind speed can significantly reduce soil moisture evaporation. field experiment also showed that: wind speed evaporation of soil moisture with a linear relationship, the higher the wind wall, the greater their sphere of influence, wind net effect is much less than the break wall.Chapter 4, according to the soil surface covered by sand and straw to reduce direct contact of air ,and to reduce influence of soil moisture evaporation with wind speed on this theory, the Combination of integrated field planting and weighing method to test the impact of covering to soil moisture evaporation impact. Experiments show: Using mulch can significantly reduce soil moisture evaporation; Farming show: using cover, even in the dry fruits and dry the desert plants can still grow normally and to bear full fruit.