不同类型防护林对沙漠土壤理化性质的影响

Effects of Different Types of Protection Forests on Physical and Chemical Properties of Desert Soil

为全面了解不同类型防护林对沙漠土壤理化性质的影响。对库布齐沙漠七星湖景区内种植年限相近的沙枣林、杨树林、旱柳林、杨树-大白柠条混合林4种类型防护林的土壤理化性质进行了测定和分析。结果表明,其中对水分影响最大的是杨树林和旱柳林;对土壤容重影响最大的是杨树-大白柠条混合林,与裸沙地相比,平均降低了0.042g/cm3;在改良土壤pH值方面,沙枣林效果最好,与裸沙地相比,平均降低了0.75;对沙漠土壤养分的影响以杨树林最大,与裸沙地相比,有机质含量增加了0.41g/kg,碱解氮含量增加了8.91mg/kg,速效钾含量增加了86.52mg/kg,但速效磷减少1.09mg/kg。试验结果还表明,各类型防护林都不同程度增加了土壤有机质、碱解氮、速效钾的含量,降低了速效磷的含量。

To fully understand the effects of different types of protection forests on soil physical and chemical properties of the desert,the soil properties of elaeagnus forest,poplar forest,salix forest and poplar-white caragana mixed forest planted for similar years in Qixing Lake of Kubuqi Desert were studied.Results indicated that the salix and poplar forests had the greatest impact on water;the poplar-white caragana mixed forest had the greatest impact on soil bulk density,averagely reduced by 0.042 g/cm3 compared to the bare sand;in improvement of soil pH value,the best was the elaeagnus forest,which averagely reduced it by 0.75 compared to the bare sand;the poplar forest had the greatest impact on desert soil nutrients,with organic matter,available N and available K contents increased by 0.41 g/kg,8.91 mg/kg,and 86.52 mg/kg,respectively,but available P content was decreased by 1.09 mg/kg,compared to the bare sand.The results provided theoretical basis for improving desert soil by the vegetation measure.