科尔沁沙地小叶锦鸡儿人工林防风固沙及改良土壤效应研究

Study on the Effects of Protection against Wind, Sand-fixation and Soil Improvement of Caragana microphylla Plantations in Horqin Sand Land

为探讨小叶锦鸡儿防风固沙、改良土壤养分状况和生物活性的能力，选取6年和11年生小叶锦鸡儿人工固沙林为对象，以流动沙丘为对照，研究不同年龄固沙林降低风速和风沙流结构特征、土壤有机质和N，P含量、土壤酶的活性以及微生物生物量C，N，P含量的变化特征。结果表明：在小叶锦鸡儿灌木林内，各个高度风速和输沙量均显著低于流动沙丘，防风固沙效果明显。随着小叶锦鸡儿固沙群落发育时间的增长，其综合防风性能提高，土壤有机质、N，P，K含量和生物活性逐渐得到改善。0～30cm土层中磷酸单酯酶、蛋白酶、脲酶、蔗糖酶、硝酸还原酶、多酚氧化酶、脱氢酶的活性和土壤微生物生物量C，N和P含量均大幅度提高，其中0～10cm土层增幅最大。土壤酶巾蔗糖酶的活性增加最为迅速，6年和11年生固沙林0～10cm土层分别是流动沙丘的28．58倍和55．2I倍。小叶锦鸡儿不仅具有较好的防风固沙性能，而且表现出强大的改善土壤养分和生物活性的能力，可作为优良的同沙植物材料在科尔沁沙地大面积推广应用。

In order to approach the effects of Caragana microphylla plantations in protection against wind, sandfixation and improvement of soil nutrient conditions and biological activity, in this study the 6- and I 1-year C. microphylla plantations are selected to research the characteristics of the plantations in wind velocity reduction, sandfixation and sand-driving wind and the change characteristics of edaphons, enzyme activity and contents of soil organic matter, N, P and K at soil depths of 0 - 10, 10 - 20 and 20 - 30 cm. The results show that the effects of protection against wind and sand-fixation of C. microphylla plantations are obvious, such effects and the contents of soil organic matter, N, P and K are gradually increased with the growth of C. microphylla plantations. Moreover, the activities of phosphomonoesterase, saccharase, protease, urease, dehydrogenase, polyphenol oxidase and ni- trate reductase and the contents of edaphon C, N and P aresignificantly increased at soil depth of 0 - 30 cm, especially at soil depth of 0 - 10 cm. In the enzyme activities, the increase of saccharase activity is the most significant, and the soil content at depth of 0 - 10 cm under the 6-and 11-year C. microphylla plantations are 28.58 and 55.21 times of those on mobile dunes. Therefore, C. microphylla can be regarded as a fine plant species to plant for protection against wind and sand-fixation in the Horqin Sandy Land.