风沙区不同配置农田防护林防护效应及其对农田土壤水分的影响

[目的] 明确风沙区不同配置农田防护林产生的防护效果差异以及影响田间土壤含水率的作用因子，为该地区水分管理和土地利用提供理论依据。 [方法] 选择南疆阿拉尔市十团3种典型配置的农田防护林，研究不同配置防护林内土壤含水率、风速、光照强度、空气温湿度等因素，综合分析土壤含水率变异性决定因子。 [结果] 疏透度为41%的5行新疆杨对田间小气候改善作用在0～1 H范围最显著，疏透度为47%的1行胡杨+2行新疆杨的林内有效防护距离最长，且田间土壤含水率显著大于5行新疆杨且大于4行新疆杨。5行新疆杨林内土壤含水率主要受空气温度、湿度、光照强度的影响，4行新疆杨和1行胡杨+2行新疆杨土壤含水率与防护林距离和土层深度有关。总体来看，林带疏透度对土壤含水率有直接负向作用，同时土壤容重随土层深度变化间接对含水率产生负向影响。 [结论] 合理调整农田防护林配置结构，能够提高防护林防护效益，为风沙区作物生长提供有利条件，同时促进当地水资源合理利用和可持续发展。

Protective Effects of Different Configurations of Farmland Shelterbelts in Wind-sand Areas and Their Impacts on Soil Moisture in Farmland

[Objective] The differences in protective effects generated by different configurations of farmland shelterbelts were detemined in wind and sand areas, as well as the influencing factors on soil moisture content in fields, in order to provide a theoretical basis for water management and land use in this region. [Methods] Three typical configurations of farmland shelterbelts in the Tenth Regiment of Alar City, Xinjiang Wei Autonomous Region, were studied by measuring soil moisture content, wind speed, light intensity, and air temperature and humidity within different configurations of shelterbelts. [Results] The most significant improvement in field microclimate within the range of 0~1 tree hight was observed with a shelterbelt porosity of 41% in the case of five rows of Populus alba var. pyramidalis. The longest effective protection distance within the shelterbelt with a porosity of 47% was achieved with one row of Populus euphratica and two rows of P. alba var. pyramidalis. Moreover, the soil moisture content in the field was significantly higher for the configuration of one row of P. euphratica and two rows of P. alba var. pyramidalis compared with five rows of P. alba var. pyramidalis and four rows of P. alba var. pyramidalis. The soil moisture content within the shelterbelt of five rows of Xinjiang poplar was primarily influenced by air temperature, humidity, and light intensity. On the other hand, the soil moisture content in the case of four rows of P. alba var. pyramidalis and one row of P. euphratica and two rows of P. alba var. pyramidalis was related to the distance of the shelterbelt and soil depth. Overall, the porosity of the shelterbelt had a direct negative effect on soil moisture content, while soil bulk density indirectly affected the moisture content through soil depth. [Conclusion] By adjusting the configuration and structure of farmland shelterbelts, it is possible to increase the protective efficiency of the shelterbelts and to provide favorable conditions for crop growth in sandy areas. This adjustment can also serve as a theoretical basis for regulating local water resources.