民勤绿洲枣树、杨树林带胁地规律对比研究

通过对枣树和杨树两种林带根系空间分布、林带下土壤含水率动态变化、近林带区作物产量因子空间变化的调查研究认为 :枣树林带相对杨树林带根系发育弱 ,分布范围小 ,且近林带区农田土壤含水率相对较高 ,对作物生长及产量的影响范围较小、程度低。枣树的胁地范围是 2 4 m,胁地范围内平均减产 9.1— 1 7.3%。杨树的胁地范围是 30 m,胁地范围内平均减产 1 0 .0— 2 3.1 %。

Study on Soil-Coerced Regulation of Forest Belts about Populus and Ziziphns in Minqin Oasis

Based on the researches of the root distribution, soil moisture trends and crop yields in the shelter belts of populus and ziziphns and their adjacent places ,the result shows that roots of ziziphns forest belts are weaker than that of populus root and the distribution rang is also smaller, the moisture contents of crop field near shelter belt are relatively higher than populus's, the impacts on crop growth, yields and soil coerced area are smaller too. The soil coerced range of ziziphns is 24m, average reducing yields in it is 9.1-17.3%. The soil coerced range of populus is 30m, average reducing yield in it is 10.0-23.13%.