东祁连山高寒草甸鼢鼠鼠丘土壤种子库特征

通过野外植被调查和种子萌发法分析了新鼠丘、 旧鼠丘和天然草地土壤种子库密度、 物种组成。结果表明,新鼠丘土壤种子库中种子密度为176.93±135.51 seeds/m²,旧鼠丘种子密度为1 486.15±900.78 seeds/m²,对照的天然草地种子密度为2 937.01±2 471.60 seeds/m²。新鼠丘土壤种子库中主要有3种植物,分别是萼果香薷(Elsholpzia bensa var.calycocarpa)、 波伐早熟禾(Poa poophagorum)和灰绿藜(Chenopodium glaucum);旧鼠丘土壤种子库中主要有3种植物,分别是灰绿藜、 节裂角茴香(Hypecoum leptocarpum)和波伐早熟禾;天然草地土壤种子库中主要有6种植物,分别是异针茅(Stipa aliena)、 二裂委陵菜(Potentilla bifurca)、 高原毛茛(Ranunculus tanguticus)、 黄花棘豆(Oxytropis ochrocephala)、 独行菜(Lepidium apetalum)和蓝翠雀花(Delphinium caeruleum)等。 新、 旧鼠丘土壤种子库密度差异较大,但差异不显著(P>0.05),物种构成差异较小;鼠丘与天然草地间在土壤种子库密度间差异较大,物种构成也较大。鼠丘土壤种子库中多为一年生植物种子,表明鼠丘上植物群落为高寒草甸演替的初期阶段。

Characteristics of Soil Seed Bank of Soil Pile Made by Zokor in Alpine Meadow Area in Eastern Qilian Mountains

The seed density and species of seed bank in soil pile made by zokor in alpine meadow in the eastern Qilian Mountains were studied and compared with that of the natural alpine meadow through field investigation and germination test.The result indicated that the seed density in new pile,old pile and natural meadow was 176.93±135.51 seeds/m2,1486.15±900.78 seeds/m2 and 2937.01±2471.60 seeds/m2 respectively.Elsholpzia bensa var.calycocarpa,Chenopodium glaucum and Poa poophagorum were main species in new pile seed bank.Chenopodium glaucum,Hypecoum leptocarpum and Poa poophagorum were main species in old pile seed bank.Lepidium apetalum,Delphinium caeruleum,Stipa aliena,Potentilla bifurca,Ranunculus tanguticus and Oxytropis ochrocephala were main species in natural meadow seed bank.The difference of seed density was greater but not for the species composition between old and new piles.The difference of both seed density and composition was great between soil piles and natural meadow.Most seeds in soil seed bank of soil piles were annual species and this suggested that the succession of vegetation was in early phase.