土壤线虫群落对闽北森林植被恢复的响应

为了考察地上植物群落的演替与土壤线虫群落的相互关系, 作者对闽北退化常绿阔叶林不同恢复阶段的土壤线虫群落进行了为期一年的定位研究。研究表明, 线虫群落对植被不同恢复阶段有不同的响应, 各恢复阶段线虫数量差异显著(P<0.01), 从大到小依次为: 荒地(Wj)、天然阔叶林(Cc)、针阔混交林(Clc )、针叶林(Pm); 土壤线虫数量的季节波动明显, 属数与个体密度均体现为春季＞冬季＞秋季＞夏季, 而夏季极显著少于其他季节(P<0.01); 土壤线虫群落DG指数与丰富度指数从大到小依次为天然阔叶林、荒地、针阔混交林和针叶林。而多样性顺序却表现为: 荒地>天然阔叶林>针阔混交林>针叶林; 不同恢复阶段土壤根系生物量、土壤理化特征存在明显的空间变异, 并且线虫数量与根系生物量、土壤含水率、土壤孔隙度、土壤有机质、全氮以及速效磷具有显著正相关关系。因此, 植被恢复过程中土壤线虫群落结构分异及其动态是一个重要的生态响应过程, 能为进一步研究土壤生物在植被演替中的地位和作用以及土壤生物多样性保护提供基础数据。

Soil nematode community response to vegetation restoration in northern Fujian

To understand the response of soil nematode communities to vegetation restoration, we surveyed soil nema-todes in a wasteland (Wj), a natural broad-leaved forest (Cc), a conifer-broadleaved mixed forest (Clc), and a coniferous forest (Pm) in northern Fujian from September 2003 to August 2004. A total of 142,005 nematode individuals were collected, belonging to two classes, four orders, 10 families and 24 genera. The results indicated that the number of soil nematode varied significantly (P<0.01) in response to different restoration stages of vegetation, ranking Wj > Cc > Clc > Pm. Nematode numbers also fluctuated with season. Both genera number and individual density ranked spring > winter > autumn > summer. Richness and DG indices ranked Cc >Wj > Clc > Pm, while Shannon-Wiener index Wj >Cc > Clc > Pm. Root biomass and soil physical and chemical characters were different at the four restoration stages. Nematode numbers were positively correlated with root biomass, soil water, soil porosity, organic matter, total N, and available P. We conclude that the dynamics of nematodes are an important biological indicator for vegetation restoration.