Abstract:

In order to further understand the evolution of soil arthropod diversity in desert area farm land, under similar farming system and fertilizing and irrigation management measures, 4 types farmland was closed as sample fields at Horqin sandy area, including no tillage, cultivated for 3 a, 10 a and 20 a. Soil arthropods from different types of farmlands were collected to find out effects of longterm farming in desert area farmland on soil arthropod diversity. The results indicated that soil water content, pH, organic carbon and total nitrogen contents in farmland cultivated for 20 a were higher. Soil properties of no tillage farmland, cultivated for 3 a and 10 a were similar. In desert area, the length of cultivation had profound influence on soil environment. All together 216 soil arthropods were collected. They belonged to 3 classes and 10 items. Among them, Acarus and Collembora were superior genus; Corrodentia, Araneida, Coleoptera, and Hymenoptera were common genus. The density of soil arthropods in no tillage farmland was the highest, followed by farmlands cultivated for 10 a and 20 a. The number of individual soil arthropods in faunal cultivated for 3 a was the least. Correlation analysis indicated that soil pH at different tillage time might be the important factor for diversity distribution of soil arthropods. Initial study also showed that in desert area farmland no tillage was favorable for individual soil arthropod to survive. Short period cultivation (<10 a) was not favorable for soil arthropod to settle down, but longterm cultivation (>20 a) was propitious to improve and maintain soil arthropod diversity, thus facilitating the protection of soil diversity in desert area farmland and management of farmland ecosystem in Horqin sandy land.

Key words: desert area farmland, cultivation, soil arthropod, community diversity, Horqin sandy area

摘要：

为了深入认识沙区农田土壤节肢动物多样性演变规律，在相近种植制度与施肥灌溉管理措施条件下，选择科尔沁沙地免耕翻、耕作3 a、耕作10 a和耕作20 a 4种类型农田为研究样地，采集了不同类型农田生境中土壤节肢动物，研究了沙区农田长期耕作对土壤节肢动物多样性的影响。结果表明：耕作20 a农田土壤含水量、pH、有机碳和全氮含量较高，免耕农田与耕作3 a和10 a农田土壤性质相近，沙区农田耕作时间对土壤环境产生了深刻影响。4种农田共采集216只土壤节肢动物，隶属3纲10目，其中蜱螨目和弹尾目为优势类群，啮虫目、蜘蛛目、鞘翅目和膜翅目为常见类群。免耕农田土壤节肢动物密度最高，其次是耕作10 a和20 a农田，耕作3 a农田土壤节肢动物个体数最少。耕作20 a农田土壤节肢动物类群数和多样性较高，其次是耕作10 a和免耕农田，耕作3 a农田土壤节肢动物类群数和多样性最低。相关分析表明，不同耕作年限土壤pH可能是影响不同耕作农田土壤节肢动物群落多样性分布的重要因素。初步研究表明，沙区农田免耕有利于土壤节肢动物个体存活，短期耕作活动（<10 a）不利于土壤节肢动物定居，但长期耕作（>20 a）有利于提高和维持土壤节肢动物多样性，从而有利于沙区农田土壤生物多样性保育和农田生态系统管理。

关键词: 沙区农田;耕作;土壤节肢动物;群落多样性;科尔沁沙地