围封对退化温性荒漠草原植被和土壤的影响

发布时间：2018-12-08 07:03

【摘要】：本文以内蒙古鄂尔多斯市鄂托克旗不同围封年限的退化温性荒漠草原为研究对象,测定不同处理下草原植物的高度、盖度、密度、地上现存量、地下生物量(分层)和凋落物量,计算α多样性指数；同时,对各处理分层取土,测定其理化性质和微生物数量。通过以上指标的监测,探讨围封年限对退化温性荒漠草原植被和土壤的影响,并应用主成分分析,对包括植被特征和土壤理化性质的共16项指标的综合评分进行比较。结果表明：(1)围封可增加草原植物群落的Margalef丰富度指数、Shannon-Wiener指数和Pielou均匀度指数,降低草地的Simpson优势度指数。围封10年的草原Margalef丰富度指数下降。(2)围封可增加草原地上现存量,地下生物量和凋落物量。凋落物量随着围封年限的增加而增加。但围封10年的草原地上现存量和0～10cm层地下生物量有所下降。(3)围封可以增加土壤有机质、全氮、全磷、全钾含量。但围封10年,会使土壤全磷和全钾的含量下降。(4)对16个植被和土壤指标进行主成分分析,各处理的综合得分大小依次为3年围封区10年围封区自由放牧区。
[Abstract]:In this paper, the degenerative temperate desert steppe in Ertok Banner of Erdos City, Inner Mongolia, was used as the research object. The plant height, coverage, density and standing stock on the ground were measured under different treatments. Underground biomass (stratification) and litter amount were used to calculate 伪 diversity index. At the same time, the physicochemical properties and microbial quantity of each treatment were determined. Through the monitoring of the above indexes, the influence of the enclosed years on the vegetation and soil of degraded temperate desert steppe was discussed, and the comprehensive scores of 16 indexes, including vegetation characteristics and soil physical and chemical properties, were compared by principal component analysis (PCA). The results showed that: (1) Enclosure could increase the Margalef richness index, Shannon-Wiener index and Pielou evenness index, and decrease the Simpson dominance index of grassland plant community. The Margalef richness index of the steppe was decreased after 10 years of enclosure. (2) Enclosure could increase the aboveground standing biomass, underground biomass and litter amount of steppe. The amount of litter increased with the increase of enclosing years. However, the aboveground standing stock and underground biomass of 0~10cm layer decreased after 10 years of enclosure. (3) Enclosure could increase the contents of soil organic matter, total nitrogen, total phosphorus and total potassium. But the contents of total phosphorus and potassium decreased after 10 years of enclosure. (4) 16 vegetation and soil indexes were analyzed by principal component analysis. The comprehensive scores of each treatment were 3 years, 10 years, and 10 years, respectively.
【学位授予单位】：内蒙古农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S812

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