基于物种性状的两种高寒草甸优势禾草对施肥的响应  

Responses of two dominant grasses to fertilization based on species traits in an alpine meadow

作　　者：胡文祥[1] 李伟[1] 杜国祯[1] 

机构地区：[1]兰州大学干旱与草地生态教育部重点实验室,兰州730000

出　　处：《兰州大学学报（自然科学版）》2011年第6期68-74,共7页Journal of Lanzhou University(Natural Sciences)

基　　金：国家自然科学基金重点项目(40930533)

摘　　要：以青藏高原东部高寒草甸优势牧草垂穗披碱草和线叶嵩草为研究对象,在野外条件下,研究了垂穗披碱草和线叶嵩草的高度、分蘖数、叶片数、比叶面积、叶氮质量分数等五个植物性状以及它们在群落中相对多度对四种不同施肥处理的响应.结果表明:随着施肥量的增加,垂穗披碱草的高度、分蘖数、叶片数、比叶面积、叶氮质量分数和相对多度显著增加.线叶嵩草的高度、叶氮质量分数随着施肥量的增加显著增加,但增加幅度小于垂穗披碱草的;施肥对线叶嵩草的分蘖数、叶片数和比叶面积没有显著影响;随着施肥量的增加,线叶嵩草的相对多度显著下降,这与垂穗披碱草相反.两种优势牧草的物种性状以及它们在群落中的相对多度的显著差异反映出两种牧草对施肥有不同的可塑性,垂穗披碱草比线叶嵩草更能适应高施氮条件.Using dominant grass Elymus nutans and Kobresia capillfolia in the eastern Qinghai-Tibetan plateau as target plants, the responses of height, number of tillers, number of leavers, specific leaf area, leaf N content and species relative abundance of the plants to different fertilization treatments were studied in the field condition. The results showed that Elymus nutans possessed a high plasticity in all five traits and SRA and they increased significantly with each additional fertilization rate. The height and leaf N content of Kobresia capillfolia also increased significantly, but the increase rate was less than Elymus nutans; fertilization had no significant effect on the number of tillers, number of leaves and of Kobresia capillfolia; species relative abundance （SRA） of Kobresia capillfolia significantly declined with fertilization, which was inverse with Elymus nutans. Differences in the morphological plasticity and species relative abundance between Kobresia capiUfolia and Elymus nutans indicated that they had different plasticity; to fertilization. Elymus nutan was more adaptive to high fertilization than Kobresia capillfolia.

关 键 词：施肥 性状 垂穗披碱草 线叶嵩草 青藏高原 

分 类 号：Q145[生物学—生态学]