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以竹-阔、竹-杉、竹-荒界面为研究对象,采用样带调查的方法对毛竹(Phyllostachys edulis)扩展过程中主要群落结构指标进行了研究,结果表明:随着毛竹向阔叶林扩展,毛竹胸径、生物量、叶面积指数、凋落叶现存量、C、N、P含量及C∶P、N∶P降低;毛竹向杉木林扩展,扩展前沿的毛竹胸径和生物量较低,扩展中段毛竹的胸径和生物量较高,叶面积指数、凋落叶现存量和C、N含量随着毛竹比例的增加而降低,凋落物P含量和凋落物C∶P和N∶P随着毛竹比例的增加而增加;毛竹向撂荒地扩展,胸径、生物量、叶面积指数和凋落物量随着毛竹立竹度的增加而增加,凋落物C、N、P含量降低,C∶P、N∶P增加。综上所述,毛竹在向阔叶林、杉木林和荒地扩展时,胸径和生物量、叶面积指数和凋落物数量和质量都发生了适应性改变。其中,毛竹向阔叶林扩展时,通过增大个体胸径和叶面积指数来适应竞争环境,扩展前沿较多的凋落物量和较高的C、N、P含量,增加了养分归还潜力,会进一步促进毛竹的生长;毛竹向杉木林扩展时,通过增加叶面积指数来适应竞争环境,随着毛竹林的扩展毛竹胸径增加、凋落物C∶P、N∶P增加,毛竹生长受到P的制约减弱;毛竹向撂荒地扩展,通过减小个体大小、降低叶面积指数来适应撂荒地相对极端的环境条件,随着毛竹的扩展个体胸径增加,凋落物量增多,P含量和N∶P增加。
Taking the bamboo-broad, bamboo-fir and bamboo-wasteland as the research objects, the investigation of the main community structure of Phyllostachys edulis during the extension process was carried out by means of transect survey. The results showed that with the development of bamboo to broad-leaved forest The bamboo diameter, biomass, LAI, C, N and P contents and C: P and N:P decreased. The bamboo expanded to Cunninghamia lanceolata, The diameter and biomass of bamboo in the middle stretch of expanded bamboo were higher. The leaf area index, leaf litter content and C, N content decreased with the increase of the proportion of Phyllostachys pubescens. The content of litter P and litter C: P and N: The proportion of bamboo increased to the abandoned land. The DBH, biomass, leaf area index and litter amount increased with the increase of Phyllostachys pubescens Phyllostachys pubescens C, P, N and P in litter, C: P, N : P increase. To sum up, when bamboo leaves expand to broad-leaved forest, Chinese fir plantation and wasteland, the DBH and biomass, leaf area index and quantity and quality of litter have all changed adaptively. Among them, bamboo expanded to broad-leaved forest by increasing individual DBH and leaf area index to adapt to the competitive environment, expanding the forefront of litter and higher C, N, P content, increasing the potential for nutrient return will be further And the growth of Phyllostachys pubescens was promoted. When Phyllostachys pubescens forest was expanded, the leaf area index was increased to adapt to the competitive environment. As the DBH of Phyllostachys pubescens increased, C: P and N: P of litter increased and the growth of Phyllostachys pubescens reduced by P ; Phyllostachys pubescens extension to wasteland, by reducing the size of individuals, reduce the leaf area index to adapt to the relatively extreme environmental conditions abandoned land, as bamboo expanded individuals increased DBH, litter increased, P content and N: P increased.