贵州无籽刺梨基地土壤及树体特征对种植年限的响应

Response of Soil and Tree Body Characteristics to Planting Ages of Rosa sterilis S.D.Shi in the Planting Bases of Guizhou Province

基于贵州喀斯特山区典型无籽刺梨种植基地的根系土壤的化学指标、物理指标和生物学指标和树体特征，采用空间替换时间的方法，对喀斯特山区无籽刺梨种植基地的土壤质量现状进行全面分析与评价，研究不同种植年限的基地的土壤质量及其树体特征对植被恢复的响应与机制。结果显示：不同林龄的无籽刺梨种植基地的土壤化学、物理和生物学指标差异明显，兴仁县（1—2a）土壤的整体变异程度大于乌当区（3～4a）和西秀区（8—9a），并随着种植年限的增加，土壤质量有所提高；无籽刺梨的冠幅、树高、叶绿素和地径呈现逐渐增加趋势，而分枝数则呈现先增加后下降趋势；兴仁县的pH（0．25）、乌当区的有机质（0．4J4）和西秀区的全磷（0．46）的隶属度均值最小，分别为三地土壤质量限制性因子；而有效磷（0．19）、有效钾（0．17）和容重（0．25）分别为三地的最大权重系数，是提高各自土壤质量的最重要因子；土壤质量综合指数分别为1．17、1．40和1．90，分别较兴仁县增加了19．69％和61．69％，增加趋势明显。研究表明，无籽刺梨的种植有利于贵州喀斯特山区土壤质量的改善，可作为中度、轻度和潜在石漠化地区生态重建的经济树种。

The typical planting bases of Rosa sterilis S.D.Shi with different ages were investigated to study the root-soil quality （chemical, physical and biological items） and these tree body characteristics in the Karst mountainous regions of Guizhou Province. This paper analyzed and evaluated soil qualities in these regions based on the methods of replacing space with time and studied the response vegetation restoration. The results showed that there biological items of soil quality. The variation degrees mechanism of soil qualities and were obvious differences among tree body characteristics to the chemical, physical and of soil samples were generally higher in Xingren County in comparison with that in Wudang and Xixiu Districts, and soil quality was improved with the planting age. Canopy, height, chlorophyll and ground diameter of fruit trees showed the gradually increasing trend, however, the divarication was first in an upward trend and then in a downward mode. Moreover, the mean memberships of pH value （0.25） in Xinren County, organic matter （0.44） in Wudang District and total phosphorus （0.46） in Xixiu District were the lowest and these three factors were the principal limited factors correspondingly in the three different areas. The important factors to improve soil quality were available phosphorus （0.19） and potassium （0.17） and bulk density （0.25） with the biggest weight coefficients in these three areas. The integrated indexes of soil quality significantly increased by 19.69% and 61.69%, respectively, in Wudang District and in Xixiu District than in Xinren County with a value of 1.17. The plantation of these fruit trees were beneficial for the improvement of soil quality in Karst mountainous regions, which could be used as economic trees for ecological restoration of slight or latent rocky desertification areas in Guizhou Province.