潮棕壤线虫群落对土地利用方式的响应

作者对潮棕壤不同土地利用方式(旱田、撂荒地和林地)下土壤线虫群落时空分布特征进行了研究, 结果表明, 不同土地利用方式能够影响线虫群落及其优势属的时空分布。线虫优势属对不同土地利用方式的响应不同, 撂荒地和林地处理中板唇属(Chiloplacus)线虫主要分布在5–30 cm土层, 而其他线虫优势属则主要分布在0–20 cm土层; 在旱田处理中, 短体属(Pratylenchus)线虫均匀分布在各个土层。由于土地利用方式的改变而引起的土壤环境因素的变化能够对土壤线虫产生影响, 研究发现土壤孔隙度、土壤有机碳、全氮和碳氮比与土壤线虫优势属的数量具有显著的正相关关系。线虫区系分析结果表明, 撂荒地和林地处理中土壤环境相对稳定, 土壤食物网向较成熟的阶段演替。线虫区系分析方法可用来揭示不同土地利用方式下土壤食物网的变化, 为进一步研究土壤生态过程对土地利用方式的响应提供了有效的工具。

Responses of nematode communities to land use in an aquic brown soil

The seasonal and vertical distribution of soil nematode communities under three contrasting land uses, i.e., cropland, abandoned cropland and woodland, was conducted in an aquic brown soil. The results showed that land-use types affected the spatio-temporal distribution of soil nematodes and their dominant genera, and different dominant genera showed different responses to land uses. In the abandoned cropland and woodland, most dominant genera were present in the 0-20 cm layers and Chiloplacus was mainly dis- tributed in the 5-30 cm layers, while in the cropland Pratylenchus exhibited an even distribution from the 0-5 to the 40-50 cm depths. Soil environmental parameters under different land uses could influence soil nematodes; soil porosity, total organic C, total N and the C/N ratio were found to positively influence the abundance of some dominant genera in the present study. The faunal profiles revealed that the environmental stability and the homeostasis of the abandoned cropland and woodland lead to higher levels of community structure and the soil food web tend to succeed to maturity. Nematode faunal analyses were found to be a useful method for interpreting the stress or/and nutrient conditions under different land uses.