高速公路路域边坡人工植被下土壤质量的变化

Changes of Soil Quality on Expressway Side Slope as Impacted by Artificial Vegetation

在呼集高速公路卓资段路堑边坡,从2003和2004年开始建立人工植被。2005年在2个不同种植年龄和同种植被类型的样地内采集土样,分析了土壤的物理性状变化、养分变化和生物活性。人工植被建立对土壤理化性状改良和成土发育产生了深刻的影响,并随着植被建立时间的延长而逐渐增大。同时由于受到不同植被类型和人为措施的影响,使得相同种植时间的不同样地,土壤性质的变化有差异。综合考虑了土壤物理、化学和生物因子,建立了土壤质量综合评价指标体系,并利用多元统计方法,对人工植被建立过程中土壤质量的变化进行了综合评价。研究结果表明,有人工植被边坡土壤质量明显高于自然恢复边坡和新挖裸露边坡,土壤质量增长显著。由于边坡植被尚未形成稳定群落,以及人工管护的力度差异,土壤质量变化随时间有所起伏,表现为种草2 a的边坡土壤质量明显优于种草3 a的边坡。

Artificial vegetation was set up on the slope in the Zhuozi County section of Hohhot-Jining expressway in 2003 and 2004. By contrast to bare slope, soil properties have changed remarkably and have increased with plantation time. A comprehensive evaluation index system for soil quality based on soil physical, chemical, and biological properties is established. Based on the system method and multivariate statistics, the changes of soil quality during soil formation on expressway slope are evaluated. The work is expected to reveal the changes of soil quality and the coupling relationship between vegetation and soil. Using SPSS analysis software, the membership function value, component capacity, and weights of soil quality factors by PCA are calculated and then the SQI （soil quality index） values for all plots are calculated. Results show that soil quality has increased since artificial vegetation was set up. The SQI values indicate that soil quality does not change with the time of artificial vegetation extending. Because management measures are different annually and artificial vegetation does not form a steady community, the SQI value for 2-year plantation plot is higher than that for 3-year plot. Among all plots, the highest SQI value is 0. 649, which is distinctly higher than other plots.