Effects Of Different Grayel Mulching On Soil Evaporation

Gravel cover can effectively reduce the soil evaporation and keep soil moisture. In this article, we probed into the relationship of soil moisture evaporation from desert region in Zhongwei Xiangshan with the change of time through field sampling and indoor simulation experiment with point of view as different thickness, particle size, color and types of gravel of gravel. We analyze the influence between cumulative evaporation, evaporation process and different thickness, particle size, color and types of gravel. The main research contents and conclusions are as follows.(1) No matter how gravel thickness, particle size, type and color changes, the average daily soil evaporation gravel were lower than that of no mulch. Meanwhile, no mulch soil evaporation distribution kurtosis and skewness coefficient is higher than that of gravel mulch treatment.(2) With the increase of cover thickness and the decrease of particle sizes, the daily soil evaporation capacity reduce gradually and the water content increased gradually. The daily soil evaporation for dark covering gravel is higher than light-colored gravel and the irregular gravel covers’ daily soil evaporation is higher than that of pebble and flake stone. The variable coefficients of daily soil evaporation are greater than0.1under different gravel covering treatment, which show moderate variability.(3) The cumulative evaporation increases with gravel mulch size, the maximum cumulative evaporation in grain diameter of4.0-5.0cm, while0.7-1.0cm is the smallest; the maximum cumulative evaporation is for purple gravel, the white gravel lesser and blue gravel with lessest maximum cumulative evaporation. The cumulative evaporation for irregular gravel is the maximum, while the difference of cumulative evaporation for pebbles and flaky are smaller.(4) The cumulative evaporation of gravel coverage for different thickness and different particle size is a quadratic power function with the increase of evaporation time, and the correlation coefficient can reach over0.94.In a word, gravel can prevent water loss and promote the sustainable development of dryland agriculture through the study of soil moisture evaporation process with different thickness, size, types and colors of gravel.