生态环境学报2024，Vol.33Issue(7)：1063-1071,9.DOI:10.16258/j.cnki.1674-5906.2024.07.007
长江源区北麓河流域退化高寒草甸植物群落特征和土壤特性
Plant Community Characteristics and Soil Characteristics of Degraded Alpine Meadows in the Beilu River Basin of the Yangtze River Source Area
摘要
Abstract
Ecosystem degradation poses a serious threat to the global ecological and environmental security.A complete understanding of the degradation process and its mechanisms is crucial for restoring the degraded ecosystems.Most previous studies on alpine meadow degradation lack long-term observational data,making it difficult to reasonably analyze the formation process and mechanism of degradation.This study focused on non-degraded,moderately degraded,and severely degraded alpine meadows in the Beilu River Basin of the Yangtze River source area.Based on the actual situation in the research area,the vegetation community and soil physicochemical characteristics of alpine meadows in permafrost areas,as well as their response to grassland degradation,were explored to provide a basis for understanding the degradation process and restoration of degraded alpine meadows in permafrost areas.The results showed that:1)with the intensification of degradation in alpine meadows,both aboveground and belowground biomass significantly decreased,the dominant species of vegetation communities shifted from grasses and sedges to forbs,and deep-rooted plants increased.2)The species richness and Shannon-Wiener diversity indices both showed a trend of first increasing and then decreasing with increasing degrees of degradation.3)As the degree of degradation intensified,the soil bulk density,pH,and total phosphorus increased,whereas the total nitrogen,organic carbon,nitrate nitrogen,ammonium nitrogen,and available nitrogen decreased.4)Redundancy analysis showed that the community biomass was positively correlated with soil organic carbon,total nitrogen,nitrate nitrogen,ammonium nitrogen,available nitrogen,and available phosphorus.Shannon Wiener diversity index and species richness index are negatively correlated with silt,water content,and pH,the explanatory rates of available nitrogen,available phosphorus,and soil moisture on vegetation biomass and species diversity were 57.8%,27.3%,and 9.9%,respectively.Therefore,plant growth in degraded alpine meadows in the source area of the Yangtze River may be limited by available nutrients.In the restoration process,the restoration of soil nutrients should be considered first.关键词
高寒草甸/草地退化/青藏高原/理化特征/群落结构/多年冻土区Key words
alpine meadows/grassland degradation/Qinghai-Tibet Plateau/physico-chemical characteristics/community structure/permafrost zone分类
农业科技引用本文复制引用
李成阳,梁志辉,李臻明,蔡敏,许瑞瑶,陈秀宇,丁佳音,许秋云,彭飞..长江源区北麓河流域退化高寒草甸植物群落特征和土壤特性[J].生态环境学报,2024,33(7):1063-1071,9.基金项目
国家自然科学基金项目(42301345) （42301345）
岭南师范学院人才专项资助项目(ZL22031) （ZL22031）
