北京地区夏季高温常常影响农作物的生长发育,降低产量,研究在高温干旱季节降低土壤温度,对提高作物产量很有意义。农作物的热量来源主要来自太阳能以及土壤、作物等表层温度的变化,取决于吸收太阳辐射能的多少。物体表面颜色的差异对太阳能吸收的强弱不同,黑体反光弱,吸光强,升温高, The summer high temperature in Beijing often affects the crop growth and development, reduces the yield, and studies the reduction of soil temperature during the high temperature and the dry season are of great significance for increasing the crop yield. The main source of heat for crops comes from the solar energy and the changes in the surface temperature of crops and so on, depending on how much solar radiation is absorbed. The difference of the color of the surface of the object is different to the strength that the solar energy absorbs, the black body reflects the light weakly, the light absorption is strong, the temperature rises is high,