陕北林地啮齿动物群落结构研究

Study on the Rodent Community Structure in Shaanxi Northern Forest Land

草兔和鼢鼠的优势度从北向南依次降低,而松鼠和黄鼠依次增加,其余种类表现为中间小,两边大。退耕群落中草兔、鼢鼠、跳鼠、田鼠、沙鼠和鼠兔的优势度高于荒坡群落,而松鼠和黄鼠的优势度退耕群落低于荒坡群落。在吴旗群落中危害刺槐的关键种是中华鼢鼠,对油松和侧柏幼林造成严重危害的是草兔。在退耕群落中对林木造成危害的主要是鼢鼠和草兔。鼢鼠、松鼠、黄鼠和鼠兔的生态位宽度以吴旗风沙区群落→退耕群落→黄土丘陵灌木疏林群落依次缩小。鼢鼠在桥山群落中与各种啮齿动物均有很高的相似性,而在桥北群落中,与其它种类的相似性比例较小。在灌木疏林群落中,鼢鼠与其它种类的相似性大于退耕群落。从主成分群落排序分析,鼢鼠在吴旗风沙区群落中与其它种类的相似性较大,而在退耕群落中的最小。

The advantage degree of Myospalax spp. and Lepus capensis gradually weakens from the north to the south, but that of Eutamias spp. and Citellus dauricus gradually increases, wheras other species show the center weakness, the both sides greatness. The advantage degree which Lepus capensis, Myospalax spp., Dipus sagitta, Allactaga sibirica, Microtus spp., Meriones spp. and Ochotna daurica communifies in the forests converted from farmland performs higher than that in the wasteland community, but the advantage degree of Eutamias spp. and Citellus dauricus in the forests community converted from farmland is lower than that in the wasteland community. In Wuqi, the key species harming Robinia pseudoacacia is Myospalax fontanieri, and that harming Pinus tabulaeformis and Platycladus orientalis is Lepus capensis. In the forests community converted from farmland, the key species harming forest are Myospalax spp. and Lepus capensis. From the Wuqi sand blown area to the returning woodland to the wasteland, the niche breadth of Myospalax spp., Eutamias spp., Citellus dauricus and Ochotna daurica decreases in order. In Qiaoshan community,Myospalax spp. and other rodents all contain very high proportional similarity, wheras low proportional similarity in the Qiaobei community, the proportional similarity of Myospalax spp.in the wasteland community, and other rodents is greater than that in the forest community converred. According to the principal components analysis, the proportional similarity of Myospalax spp. and rodents in the Wuqi sand blown community is biggest smallest, but in the forests community returned from farmland.