Study On The Environmental Field Of Farmland Windbreak Network

Two windbreak networks were selected for field study in Kerqin sandy land, one is in Ganqika County, Inner Mongolia, and the other one is in Changtu county, Liaoning province. Wind speed, soil moisture, and soil temperature of shelter area were investigated both in April and August. Data were made into counter maps and 3D wirefare maps by applying Kriging interplotation in Software surfer, and analyzed using classical statistics and Geostatistic method. The spatial characters of windbreak environmental field in these two places were discussed in this study.Results from the classical statistics show that: wind speed in spring is much higher than that in summer in both two fields; the difference is that the variation of wind speed in spring is larger than that in summer, but the trend is opposite in Changtu; vertically, wind speed increases with the increase of height; variation of wind speed decreases with the increase of height in Ganqika, and in the summer of Changtu, but in spring is another way around.The seasonal variance of soil temperature is significant; the difference between summer and spring is 11.8℃in Ganqika, and 17.7℃in Changtu.The spatial characters of soil moisture in shelter area: soil water content in summer is 3.41 higher than that in spring in Ganqika, and in Changtu the difference is 14.8. The variation of soil moisture in Ganqika is summer>spring, in Changtu is opposite.Results of comparison among different layers show that the distribution characters of soil moisture in the depth of 0-15cm, 15-30cm, 30-45cm, 45-60cm are similar: the water content is lower and gradient is larger near the shelterbelts than in the middle part of the windbreak network.Results of geostatistic analysis show: all windspeed investigated in Ganqika fit spherical model except that at the height of 2m in spring; all wind speeds in Changtu fit exponential model except that at 2m high in summer. The range of spatial autocorrelation from big to small is: 1m, summer> 1m, spring> 2m, summer> 2m, spring in Ganqika, and 1m, spring>1m, summer> 2m, spring> 2m, summer in Changtu. The rate of...