柯柯牙地区不同林龄新疆杨防护林土壤养分变化

Variation of Soil Nutrient with Populus bolleana Shelterbelt Forest at Different Ages

为研究新疆阿克苏柯柯牙地区不同林龄新疆杨防护林土壤养分变化状况,评价新疆杨防护林土壤改良效果,以1987、2008、2017年营造的林地和裸露沙地(对照)为研究对象,采取野外实地采样和室内化验分析法研究了土壤含水量、pH值以及全盐、速效磷、速效钾、有机质、钠离子等含量的变化。结果表明:与裸露沙土相比,新疆杨防护林土壤速效磷、速效钾和土壤有机质含量均显著增加,且含量随着林龄增大而显著增加,土壤养分含量明显提高。与对照相比,防护林土壤钠离子、土壤全盐含量和土壤pH值随林龄增大呈现先降后增趋势,直至趋于相对稳定,表明新疆杨人工林在一定时间内可以显著降低土壤盐碱性,提高沙地土壤养分含量,改善土壤养分状况。土壤速效磷、土壤速效钾、土壤有机质含量及土壤含水量相互之间呈显著性正相关,表明土壤含水量影响土壤养分的含量,植物在缺水环境中吸收土壤养分,在灌溉过程中吸收水分,反而促进了土壤养分的积聚。

The study was to find out the variation of soil nutrient status in different age of Populus bolleana shelterbelt, and to evaluate the effect of poplar shelterbelt on soil improvement. The soil with poplar forest in Xinjiang which was established in 1987, 2008 and 2017, respctively, was applied as the research object, and bare sandy land was used as the control(CK). The research method was combined with field investigation and laboratory test analysis. The results showed that compared with the bare sandy soil, the contents of soil available phosphorus, available potassium and soil organic matter in the poplar shelterbelt were significantly increased, and their contents increased significantly with the increase of stand age, and the soil nutrients increased significantly. Compared with the control, the concentrations of soil sodium ions, soil total salt and soil pH decreased first and then increased with the increase of stand age, until they tended to be in dynamic equilibrium, which should be adapted to the growth characteristics of poplar in Xinjiang and local arid climate factors. Correlation analysis showed that soil available phosphorus, soil available potassium, soil organic matter and soil water content were significantly and positively correlated, indicating that they influenced each other and jointly promoted the concentration of soil nutrients.