带状皆伐后更新密度对植物多样性的影响

摘要

Aiming at the problem of loss biodiversity of Larix Olgensis plantation,five species of Quercus mongolica Fischer ex Ledebour,Quercus mongolica Fischer ex Ledebour,Juglans mandshurica Maxim,Picea koraiensis Nakai and Fraxinus mandschurica Rupr trees were artificially regenerated by two kinds of densities of 2 000 plants/hm2 and 3 300 plants/hm2 after band clear cutting of Larix olgensis henry in Meng Jiagang forest,Heilongjiang province.Two years later,the plant diversities of regenerated stand and without regeneration stand were investigated and analyzed respectively.The results showed that herb and shrub plant species of regenerated stand increased.The density,coverage and the average height were lower than without regeneration stand because the soil surface was destroyed due to the site preparation after clear cutting.After band clear-cutting of Larix olgensis henry forest,it was recommended to construct a mixed forest of needle and broad species with 2 000 plants/hm2 for its the better community diversity and more uniform individual species distribution%针对长白落叶松人工纯林带来的生物多样性减退问题,在落叶松皆伐迹地采用5个树种(柞树、红松、胡桃楸、云杉和水曲柳)按照2 000株/hm2和3 300株/hm2两种更新密度进行人工更新,2 a后,对更新与未更新林分的植物多样性进行调查分析.结果显示:采伐后更新的林分,由于整地破坏了土壤表层,草本和灌木植物的种类增加,密度、盖度和平均高均较未更新的林分低;更新密度2 000株/hm2的林分,群落多样性较好,物种个体分配比较均匀,建议在长白落叶松带状皆伐后采用2 000株/hm2的更新密营造针阔混交林为宜.