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棉花苗期中耕能否提高地温?1983年我们做了试验,中耕后5月21日—6月1日,每天7、12、19时定时观察5厘米地温变化情况,发现中耕并不能提高棉苗根区地温.中耕后表土层温度中午12时比不中耕的高1.1—1.4℃,但5厘米土温却低0.7—1.5℃(表).中耕后棉苗根区地温为什么不高?我们认为有三个原因:①表土层水分蒸发快,带走的热量多,向下传导的热量少;②中耕有保墒作用,水热容量大,使地温上升慢;③耕层内土壤结构疏松,空气增多.棉花生理活性最强的根系多分布在5厘米以下土层内,所以在无草、不板结的情况下,应少中耕或不中耕,减少人力、物力消
Cotton seedling cultivating can increase ground temperature? In 1983 we have done a test, after cultivating May 21-June 1, 7,12,19 every day to observe the changes in temperature of 5 centimeters and found that cultivation does not improve cotton seedlings Root area of soil temperature. After topsoil surface temperature at 12 o’clock no-tillage high 1.1-1.4 ℃, but 5 cm soil temperature is 0.7-1.5 ℃ lower table (Table) after the tillage cotton seedling root zone temperature is not high? We think There are three reasons: ① topsoil evaporation quickly, take away more calories, downward heat conduction less; ② tillage has the role of soil moisture, water and heat capacity, so that the temperature rise slow; ③ tillage within the soil structure loose, air increased The most physiological root activity of cotton is distributed in the soil below 5 cm, so no grass or no knot, should be less cultivated or not tillage, reduce manpower, material consumption