中文摘要：

【目的】针对土壤连作障碍问题,以土壤线虫群落结构和多样性为研究重点,分析不同种植年限土壤生态系统间的差异,进而探讨不同种植年限温室土壤的健康状况。【方法】采集8年、10年、13年和16年温室黄瓜土壤,以1年露地土壤为对照,采用线虫形态学鉴定方法,分析不同种植年限土壤线虫群落结构及多样性的变化规律。【结果】不同种植年限共观测到土壤线虫属21个,全部为优势属和常见属;线虫总数和植物寄生线虫数量在不同种植年限的分布依次为10年〉16年〉13年〉8年〉1年,线虫总数种植年限之间差异显著,范围为每100 g干土61~437条;线虫群落生态指数对种植年限有不同的响应,土壤线虫群落多样性指数H′在不同种植年限土壤中的分布为16年〉13年〉1年〉8年〉10年,均匀度指数J为13年〉16年〉1年〉8年〉10年,而优势度指数λ的分布则为10年〉16年〉13年〉8年〉1年,5种不同种植年限土壤的NCR指数在0.6~9.8之间,WI分布为1年〉8年〉13年〉16年〉10年;线虫成熟指数MI在种植16年的温室土壤中最小,相反PPI/MI值则在种植16年的土壤中最大;丰富度指数SR随种植年限呈先升高后降低,10年的最低;线虫区系分布结果显示,除种植10年黄瓜土壤的样点落在第Ⅳ象限外,其余种植年限黄瓜土壤的样点均落在第Ⅰ象限。【结论】综合分析得出,连续种植会使土壤变得贫瘠,健康状况变差,受干扰程度变大,种植10年土壤线虫多样性、稳定性最差,土壤环境已受胁迫。

英文摘要：

[ Objectives ] Aiming at the problem of soil continuous cropping obstacle, this study investigated the soil health status in greenhouses with different cultivation years, based on the community structure and diversity of soil nematode and the difference of soil ecosystems in different cultivation years. [ Methods ] Soil samples were collected in greenhouses which were continuous used for cultivation of cucumber for 8, 10, 13 and 16 years, and a control soil sample was collected in an open field nearby, in which only one season of cucumber was produced. The community structure and diversity of soil nematode were analyzed using the morphological identification method. [ Results ] There were 21 nematode genera detected in all the samples. Both the total nematode and plant-parasite nematode numbers per 100 g of dry soil were in order of 10 a 〉 16 a 〉 13 a 〉 8 and 1 a, and the total nematode number were significantly different among cultivation years, ranging from 61 to 437 per 100 g dry soil. The nematode ecological indices responded differently to cultivation years. The Shannon index （H＇） was in order of 16 a 〉 13 a 〉 1 a 〉 8 a 〉 10 a, while the evenness index （J） was in order of 13a〉16a〉la〉8a〉10a. The dominance index （k） wasintheorderofl0a〉16a〉13a〉8a〉l a. However, the Wasilewska index （WI） was in a reverse trend. For all soils the nematode channel ratio （NCR） was higher than 0.5, ranging from 0.6 to 9.8. The lowest nematode maturity index was found in the 16 year-soil, resulting in the highest PPI/MI ratio. The richness index （SR） increased firstly, then decreased gradually and finally bottomed at the lowest value in the 10-year soil. The nematode in the 10-year soil distributed in the IV quadrant, while the others distributed in the I quadrant. [ Conclusions ] The soil in the 1-year open field is low in nematode number, showing a stable soil ecosystem. Continuous cropping leads to accumulation of nematode in number but decrease in nematode genera, the soil m