鄂尔多斯高原盐沼湿地底栖动物多样性特征与遗鸥繁殖期觅食的相关性研究

The Relationship Between the Zoobenthos and Larus relictus′ Foraging Behavior in Saline-Alkaline Wetland of Ordos Plateau

遗鸥是蒙古高原荒漠-半荒漠生态条件下的特有鸟种，是国际公认的濒危鸟种，具4个相对独立的繁殖种群，遗鸥鄂尔多斯种群的春、夏季主要栖息、繁殖地是鄂尔多斯高原盐沼湿地，2006年遗鸥的繁殖地在湿地的红碱淖尔湖，所以4月-10月对鄂尔多斯高原盐沼湿地的红碱淖尔底栖动物的组成和分布及月动态变化进行调查，并且对水生昆虫的成虫和幼虫的蜕皮壳数量进行调查，以及对遗鸥在春、夏季繁殖期的觅食特点进行调查。结果表明：红碱淖尔的底栖动物种类少，只有9种，且都是水生昆虫，豆娘和摇蚊是优势种，占底栖动物总生物量的90％以上。遗鸥食物种类少，繁殖地生态环境脆弱，典型相关和多元线形回归分析显示，豆娘幼虫是遗鸥繁殖期间的主要食物，5—7月高峰期的摇蚊幼虫是遗鸥重要的食物补充来源。遗鸥与豆娘幼虫、遗鸥与摇蚊幼虫是捕食与被捕食关系，种群数量存在着消长关系。

Larus relictus are the special birds at desert ecological condition. They are in severe danger. Ordos populations of Larus relictus were found at the latest. They inhabit and breed in the salt marsh wetland of Ordos Plateau in spring and summer. Their breeding site changed from Aobai Nur and Aoken Nur to Tao - a Haizi to Hongjian Nur because their breeding condition is instability of the weather, the species composition and distribution and annual dynamic of zoobenthos in Tao - a Haizi and Hongjian Nur were investigated. Study was carried out from April to October in 2006. The relationship between the benthonic animals and the Larus relictus in saline - alkaline wetland of the Ordos Plateau was established. The results showed ： the species of the zoobenthos in HongJian Nur is less. It is only 9 kinds. Chironomidae and lschnura are the dominant species. Their biomass proportion reached 90% to the benthonic animals＇total biomass. The Canonical Correlation Analysis between benthonic animals and Larus relictus showed： lschnura is the main food for Larus relictus. The quantity Chironomidae is much more from May to July. Chironomidae is the important complement food of Larus relictus. If the ecological condition is continually deteriorated, the Larus relictus food chain would be broken. The Larus relictus would lost their inhabited site.