纸浆材桉树人工林地位指数表的编制

Establishment of a Site Index Table for Eucalyptus Pulpwood Plantation

纸浆材桉树人工林是国营雷州林业局主要森林类型。依据2015年1月调查的190块临时标准地数据,剔除优势木平均高3倍标准差范围之外的样地,符合要求的标准地有164块,等概率抽样选16块标准地作为检验数据。用哑变量的导向曲线法拟合比较了9种模型,结果表明:Logistic曲线拟合效果最好,在α=0.01时差异不显著。纸浆材桉树人工林的基准年龄为2a,龄级距为4,指数级个数为8个。选用相对优势高法导算地位指数表,落点检验表明有160块标准地优势木平均高落在地位指数表内,占比为97.6%。说明地位指数表可以很好地反映国营雷州林业局纸浆材桉树人工林立地质量。

Eucalyptus pulpwood plantation is the main forest type in Leizhou State Forestry Bureau. In this paper, based on the data collected 190 temporary sample plots which were investigated in January 2015 and getting rid of the sample plots with average height of superior trees having three times standard devia- tion,there are 164 standard sample plots which meet the requirements. Using sampling with equal probability to select 16 standard sample plots as testing data. The 9 models were compared by dummy variable guiding curve fitting method. The results show that the Logistic curve fitting effect is the best, and the difference between the observed value and the regression value is not significant in OL = 0. 01. The stand- ard age of Eucalyptus pulpwood Plantation is 2 years old, the distance of age-class is 4, index number is 8. The relatively advantage high method was used to calculate status index and impact testing showed that there were 160 standard sample plots in the site index table, accounted for 97.6%. Status index table can be a very good response to the site quality of eucalyptus pulpwood plantation in Leizhou State Forestry Bu- reau.