西宁周边山地青海云杉人工林地位级划分

Site classing of Picea crassifolia Kom.plantations on the mountain around Xining areas

为了给西宁周边山地及相似生态区提供青海云杉人工林立地质量评价标准和营造林技术指导,在西宁周边山地选择有代表性的27块样地,进行系统的优势木生长状况和立地因子调查。通过调查,分析主要立地因子对立地质量的影响,编制优势木高生长动态导向拟合方程。结果表明:指数回归方程y=-0.022x^3+1.410 7x^2-7.870 5x-64.97是树高地位级最适合的导向拟合曲线。以20 a为青海云杉基准林龄,确定按4个地位级评价立地质量。立地因子对立地质量的具体影响为低坡优于高坡,缓坡优于陡坡;阴坡优于半阴坡,半阴坡优于半阳坡,半阳坡优于阳坡,半阳坡和阳坡为贫瘠立地。

In order to provide quality appraising standard and afforestation technical guidance for site quality evaluation of Picea crassifolia Kom artificial forest on the mountain around Xining areas and similar ecological regions,27 representative sample plots on the mountains around Xining areas were selected.The growing status of dominant tree and site factors were investigated.The effects of main site factors to site quality were analyzed,dominant tree height growth curve and simulative equation were obtained.The results showed that the polynomial regression equation y =-0.022x^3＋1.4107x^2-7.8705x-64.97 was the most suitable height growth fitting curve.Based on this result,a 20 a Picea crassifolia Kom was used as the benchmark,four level status for site quality evaluation were determined.The influence of site factors to quality as following shows： The trees in lower part of the mountain is taller than the upper part of the mountain,in gentle slope than steep slope; in shady slope than semi-shady,in semi-shady slope than semi-sunny slope,in semi-sunny slope than sunny slope.Semi-sunny slope and sunny slope site are barren sites.