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了解四川盆地退耕造林对土壤线虫群落结构的影响,可为协调该区域退耕还林后土壤生态系统健康发展提供科学依据。本研究于2013年4月对四川成都周边山区造林11年的麻竹(Dendrocalamus latiflorus)人工林(DL)、巨桉(Eucalyptus grandis)人工林(EG)和邻近坡耕地(CK)3种样地土壤进行分层(0~10 cm、10~20 cm和20~40 cm)取样调查。共捕获线虫10103条,分别隶属于2纲6目22科37属,优势属为滑刃属和绕线属,常见属为丽突属、鹿角唇属、小杆属等16个属,其余为稀有属。结果显示,不同样地间土壤线虫数量差异明显,但在垂直分布上具有明显的表聚现象。土壤线虫多样性指数(H’、SR、J’)表现为DL>CK>EG,而优势度指数λ则相反;功能类群指数MI表现为DL>EG>CK,PPI和PPI/MI指数为CK>DL>EG。土壤线虫区系划分显示DL受干扰程度较小,食物网结构相对成熟,EG次之,而CK处于退化状态。以上表明,麻竹造林可丰富土壤线虫群落的种类组成和维持较高的多样性,使土壤生态系统结构和功能处于相对稳定的状态。
Understanding the impact of the conversion of cropland to afforestation on soil nematode community structure in the Sichuan Basin may provide a scientific basis for coordinating the healthy development of soil ecosystem after the conversion of cropland to forest in the area. In this study, we conducted a field survey on three plots of Dendrocalamus latiflorus plantations (DL), Eucalyptus grandis plantations (EG) and adjacent sloping farmland (CK) plots in April 2013 in the mountains around Chengdu, Soil stratification (0 ~ 10 cm, 10 ~ 20 cm and 20 ~ 40 cm) sampling survey. A total of 10103 nematodes were captured, belonging to 2 orders, 6 orders, 22 families and 37 genera, respectively. The dominant genera were Pleurotus spp. And coil spp. The common genera were 16 genera including Laminaria, Antler lip and Scirpus, and the rest were Rare genus. The results showed that the number of soil nematodes differed significantly among different plots, but there was obvious surface aggregation in the vertical distribution. The index of soil nematode diversity (H ’, SR, J’) was DL> CK> EG, but the dominance index λ was opposite. The functional group index MI was DL> EG> CK, PPI and PPI / MI were CK > DL> EG. Soil nematode fauna showed that DL was less disturbed, food web structure was relatively mature, EG was second, and CK was in a degraded state. The above shows that afforestation of bamboo can enrich the species composition of soil nematode community and maintain high diversity, so that the structure and function of soil ecosystem are in a relatively stable state.