蜀南竹海毛竹林土壤化学肥力质量及其评价

Soil Chemical Fertility Quality and Its Evaluation in A Moso Bamboo Forest of Shunan Bamboo-sea, Southwest China

以四川宜宾蜀南竹海核心景区毛竹林土壤为研究对象，按照公里网格法布点，采集0～40cm土层土样34个，测定速效钾、有机质、有效磷、pH、全氮、碱解氮、电导率7项土壤化学指标，应用地统计分析方法研究了土壤化学肥力质量。采用因子分析法对土壤化学肥力质量进行了评价。结果表明：研究区土壤速效钾和有效磷含量较低，尤其是有效磷极度缺乏；从变异系数上看，除pH为弱变异外，其余指标均为中等变异；除pH为中等空间相关外，其余指标均具有强烈的空间相关性；土壤化学肥力质量指标的空间变异范围为1062．32～1952．56m；在划分的5个化学肥力等级中，Ⅰ、Ⅱ等占总面积的38％，Ⅳ、Ⅴ等所占面积较Ⅰ、Ⅱ等小，占总面积的31．94％；Ⅲ等以上占总面积的68．06％，土壤化学肥力质量总体处于中上水平。应科学开发和规划减少人为干扰，合理施用磷钾肥。

Using kilometer grid method and global position system, in total 34 samples from the 0--40 cm soil layer were collected in September of 2014 from the moso bamboo forest of the core scenic area of Shunan Bamboo-sea, Yibin, southwest China. The contents of 7 chemical indexes of the soil samples were measured, i.e., rapidly available potassium （K）, soil organic matter, available phosphorus （P）, pH, total nitrogen （N）, alkali-hydrolyzale N and conductivity, and soil chemical fertility quality was evaluated by using factor analysis on the basis of geostatistical analysis. The contents of soil rapidly available K and available P were low, especially rapidly available K. From the view of variable coefficient, all the tested indexes had medium variation except for pH, which had a weak variation. The variation range of tested indexes was 1 062.32-1 952.56 m. All other indexes had significant spatial correlations except for pH, which only had a medium spatial correlation. Among the designated five soil fertility levels, level Ⅰ and Ⅱ combined accounted for 38% of the total investigated area, and level Ⅳ and Ⅴ for 31.94%. Levels above level Ⅲ accounted for 68.96% indicating that the soil chemical fertility quality was at a medium high level as a whole. These results suggested that the soil chemical fertility quality in the study area was at a medium level as a whole, but 31.94% of the area was at a low level which indicated the soil fertility in the moso bamboo forest needs to be improved. The above results are useful for the protection of the ecological environment and further tourism development and management of Shunan Bamboo-sea.