川南几种竹种退耕还林植被恢复研究

本文用空间代时间的方法研究了长宁县竹林退耕还林在时间序列上的植被恢复特点。除毛竹外,和一般树种相比,竹类恢复为森林的时间较短,3 a~5 a即可成林。但竹种类型间成林速度存在差异,丛生竹成林最快,散生竹较慢。梁山慈竹和硬头黄竹退耕后可以一次成林,毛竹退耕可先进行农林复合经营直到群落郁闭。随着竹林的恢复,草本层生物量逐渐减少,地被物层生物量增加,各竹种新生个体的生态位逐渐扩大。人工栽植5 a的毛竹扩散规律研究结果表明,随着毛竹栽植时间的延伸,毛竹产生的新竹数目增多,个体变大,距离变远(170 cm),也存在大小年变化。人工促进竹林植被恢复速度明显较快。

Researches on the Vegetation Recovery of Some Bamboo Species for Conversion of Land to Forest in Southern Sichuan

The vegetation recovery of bamboo forest for conversion of land to forest were investigated by using the "space for time"method in this paper.The results showed that bamboo forest recovered more quickly from land to forest more than other forests,and would form forest after 3 to 5 years.But different bamboo species exhibited different forest formation velocities,for example,the forest formation of monopodial bamboo was faster than that of sympodial bamboo.After conversion of land to forest,forests were directly formed as for Bambusa rigida and Dendrocalamus farinosus,and the agro-forestry was firstly conducted as for Phyllostaehys heterocycla var.pubescens until forming perfect community.With the recovering of bamboo forest,the biomass of grass layers gradually decreased,that of litter layers increased,and niche of all kinds of bamboo species expanded as well.There were more numbers of newborn bamboo,bigger individuals,further distance(170 cm),and conversion of big and small year as well.Summarily,it is obviously quicker to promote the vegetation recovery of bamboo forest artificially.