农林复合模式蒸散耗水的研究

Study on Evapo-transpiration on Agroforestry

应用土壤分层水量平衡模型，对林带与冬小麦的根系吸水量、林带和农田的蒸散耗水量、林带影响农田土壤水分范围与程度进行了研究，结果表明：（１）冬小麦拔节至乳熟期间，林带根系吸水以消耗农田土壤水分为主，主要表现在０．０～１．５Ｈ（Ｈ为树高）范围内。（２）林带可降低１２．３％的农田蒸散量。（３）由于林带的影响，在农田中，０．０～０．５Ｈ为土壤水分降低区，０．５～５．０Ｈ为土壤水分提高区。总体平均，０～２００ｃｍ农田土壤贮水量可提高１１．２％。

This dissertation,applying the model of soil layered water balance of agro-forestry,calculates the water uptake by the roots of wheat and shelterbelt,the evapo-transpiration, and the extent that the effects of shelterbelt exerted on the field soil water,then tostudy the evapo-transpiration of agroforestry.The results show that:(1) Water uptake byroots of the shelterbelt mostly come from the field at the jointing-filling stage of winterwheat,which is obviously indicated in 0.0H～1.5H.(2)If the field is protected by the shel-terbelt,the average evapo-transpiration is 12.3% lower than that of the open wide field.(3)The field soil water content reduces in 0. 0H～0. 5H and raises in 0.5H～5.0H because ofthe shelterbelt effect.In general,the soil water capacity at the field soil depth of 0～200 cmcan be raised by 11.2%.