【摘要】 以"空间序列"代替"时间序列"的研究方法对川西灌木高山松林不同年龄火烧迹地进行了调查研究。结果表明:灌木高山松林火烧迹地恢复早期,物种多样性波动较大,火烧后4a～5a是群落发生剧变的时期,8a～20a、20a～27a是群落结构组成连续变化的时期。生物多样性并非绝对随群落演替的顺向发展而增加,火烧后恢复2a物种数量急剧增加,但均匀度极低,随演替发展,种间激烈竞争,排斥和替代,物种数比恢复2a时有所减少,物种均匀度增加,多样性在恢复6a时达到一高峰。随演替进行,优势度的增加,物种减少,多样性逐渐变小,恢复8a～20a时期是一低谷。随演替的进一步进行,高山松幼苗幼树逐步生长形成乔木层,林地由开敞变为郁闭,物种增加,群落变得复杂,多样性又随演替发展而增加,群落中物种多样性最大值出现在恢复27a时耐荫物种和不耐荫物种同时出现的阶段。更多还原

【Abstract】 Species diversity and vegetation change in the arbor layer,the shrub layer,and the herb layer of Pinuns densata forests were studied in the burn blanks at different ages by using "the sequence of space for replacing the sequence of time" method.The results showed that the range of species diversity indexes’fluctuations was wide at the younger stage.The structure of the community changed rapidly between the 4th year and the 5th year after fire.But it altered slowly in the 8th～the 20th year and the 20th～the 27th year.Species diversity indexes didn’t always increase with the progressional community succession.In the 1th～the 2nd year there had been a sharp rise on the number of species,but the evenness indexes decreased observably.In the following stages the number of species was little than that in the 2th year but the evenness indexes were higher.The trend of species diversity indexes was a peak value in the 6th year.With the burn blank’succession the dominance increased but species diversity and the number of species decreased.The trend of species diversity indexes was a concave line in the 8th～the 20th year.With Pinuns densata seedlings growing and the arbor layer coming into being,the community became more and more complex and species diversity rose.Species diversity indexes were the highest during both shade-tolerant plants and non-shade-tolerant plants occurring at the same time.更多还原