腾格里沙漠人工植被区掘穴蚁(Formica cunicularia)的生态功能

掘穴蚁（Formica cunieularia）营筑丘活动，并通过营巢活动影响土壤的物理化学特性，是中国干旱和半干旱地区营巢的优势蚁类。在沙坡头人工固沙植被区调查了掘穴蚁对不同固沙年代和不同地形人工固沙区土壤的影响；研究了掘穴蚁的营巢活动对土壤水分、理化性质和种子库的影响。 研究结果表明：随着固沙年代的延长，掘穴蚁的筑丘活动加强；掘穴蚁筑丘活动对地形的选择顺序依次分别为：丘间低地〉迎风坡〉丘顶〉背风坡；与邻近土壤相比，蚁丘的土壤含水量升高，土壤容重（0～10cm深）、有机质、电导率、全氮、全磷、全钾、可溶性氮、可溶性磷和可溶性钾在蚁丘富集；土壤容重（10～20cm深）和pH值下降；蚁丘对土壤种子库有明显影响（p〈0．01），种子密度和多样性指数在不同取样点间的大小顺序为：苔藓结皮上的蚁丘〉苔藓结皮〉地衣结皮上的蚁丘〉地衣结皮。 在沙坡头人工固沙植被区，由于生态环境的改善，特别是土壤环境的提高，导致掘穴蚁大量定居，它的筑巢对土壤具有反馈作用，这种反馈作用导致土壤异质性增强，改善了土壤环境的状况，加速了土壤和植被的演变。

Study on the eco-functions of Formica cunicularia (Hymenoptera: Formicidae)in a revegetated area on the southeast fringe of Tengger Desert, North China

Formica cunicularia(FC) is one of the dominant mound-building ant species in arid and semi-arid regions in China.It can modify the soil parameter to a considerable extent through nest building activities.The effects of FC on soil properties,moisture,and seed bank in the Shapotou region were investigated in this paper.The results show that the longer sand is consolidated,the more active FCs are,the more effects they produce on sand.The activities of FC vary with topographic locations and more nests in hollows and windward slopes while less in dune tops and leeward slopes.The organic matter,total and available N,P and K are enriched in the soil of nests.Comparing with the adjacent soil,the bulk density of soil of ant nest is lower in depth of 10-20 cm and higher in depth of 0-10 cm, and soil electric conductivity and water content are higher.And also,both seedling density and diversity in anthill are higher than those in adjacent soil.The establishment of planted sand-binding in the Shapotou region improves the environment and provides a favorable living condition for ants.On the contrary nesting activities of ant also affected soil properties.Thanks to the ant bioturbation,soil moisture,texture,properties and seed bank had been modified,which leads to the increasing of the soil heterogeneity and improvement of soil condition,and quickens evolution of soil and vegetation.