抚育间伐强度对落叶松天然次生林林分结构及健康的影响

Effects of Different Tending Intensities on Stand Structure and Health of Larix gmelini Natural Secondary Forest

为了研究不同抚育间伐强度对落叶松天然次生林林分结构的影响,并对森林健康状况做出准确合理的评价,以大兴安岭新林林区的落叶松天然次生林14块典型样地为研究对象,综合分析林分水平结构、垂直结构、空间结构的各项指标,利用主成分分析法对落叶松天然次生林样地进行健康评价。结果表明:50%的落叶松天然次生林样地处于一般健康状态,42.86%的样地处于亚健康状态,7.14%的样地处于健康状态;综合评分结果由大到小的顺序为7号样地(19%)、8号样地(20.86%)、6号样地(16.75%)、1号样地(对照)、4号样地(12.52%)、2号样地(3.42%)、12号样地(47.87%)、10号样地(34.38%)、11号样地(40.01%)、14号样地(47.87%)、9号样地(27.85%)、13号样地(51.48%)、5号样地(13.74%)、3号样地(6.23%)。从而得出,新林林区落叶松天然次生林林分健康水平普遍偏低,在抚育强度为19%时林分综合健康水平达到最佳,为提高林区整体生态效益,改善次生林健康状况,还应制定相应的补植改造、生态疏伐措施。

The experiment was conducted to study the effect of different tending intensities on the structure of Larix gmelini natural secondary forests,and to make an accurate and reasonable assessment of its health status,with 14 typical sample plots of L.gmelini natural secondary forests in Daxing’an Mountains.The indicators of horizontal structure,vertical structure and spatial structure of forests stand were analyzed.The main component analysis method was used to evaluate the health of the L.gmelini natural secondary forests.The 50%plots were in general health status,42.86%of the plots were in sub-healthy state,and 7.14%of the plots were in a healthy state.The comprehensive scoring result in descending order was Sample plots No.7(19%),Sample plots No.8(20.86%),Sample plots No.6(16.75%),Sample plots(control plots),Sample plots No.4(12.52%),Sample plots No.2(3.42%),Sample plots No.12(47.87%),Sample plot No.10(34.38%),Sample plot No.11(40.01%),Sample plot No.14(47.87%),Sample plot No.9(27.85%),Sample plot No.13(51.48%),Sample plots No.5(13.74%),and Sample plots No.3(6.23%).Therefore,the health level of the natural secondary forests in the Xinlin region is generally low.When the tending intensity reaches 19%,the comprehensive health level of the stand is the best.In order to improve the overall ecological efficiency of the forest area and improve the health status of the natural secondary forests,appropriate replanting and ecological evacuation measures should be drawn up.