不同人为干扰下纳帕海湖滨湿地植被及土壤退化特征

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 不同人为干扰下纳帕海湖滨湿地植被及土壤退化特征 DOI: 10.5846/stxb201305211134 作者: 作者单位: 同济大学环境科学与工程学院污染控制与资源化国家重点实验室,同济大学环境科学与工程学院污染控制与资源化国家重点实验室 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金资助项目(41171074,U0933601,40771013) Analysis of vegetation and soil degradation characteristics under different human disturbance in lakeside wetland, Napahai Author: Affiliation: Key Laboratory of Yangtze River Water Environment,Ministry of Education,State Key Laboratory of Pollution Control and Resources Reuse,College of Environmental Science and Engineering,Tongji University,Key Laboratory of Yangtze River Water Environment,Ministry of Education,State Key Laboratory of Pollution Control and Resources Reuse,College of Environmental Science and Engineering,Tongji University Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:以滇西北高原纳帕海湖滨退化湿地为研究对象,对比分析了人为隔断水源补给、牛羊过度放牧和家猪拱地3种人为干扰下湿地植被和土壤退化特征。结果表明:3种干扰方式下,纳帕海湖滨湿地植物群落类型多样性、物种丰富度、物种数、Shannon-Wiener指数、沼生植物重要值以及土壤有机质、全氮、速效氮、含水率、毛管孔隙度变化规律为:人为隔断水源补给>牛羊过度放牧>家猪拱地,而土壤容重和全钾含量变化规律完全相反。Pearson相关性分析表明,不同人为干扰下相同土壤指标之间相关性质和相关强度不同;CCA分析表明植物群落种类组成和分布与土壤含水率和全磷含量显著相关。以原生湿地样点为对照,人为隔断水源补给、牛羊过度放牧和家猪拱地样带土壤退化指数分别为-7.40%、-14.53%、-45.01%。认为纳帕海湖滨湿地退化是三种干扰协同作用结果,但作用程度不同,其顺序为家猪拱地>牛羊过度放牧>人为隔断水源补给。 Abstract:Wetland degradation is the core issue of wetland science field. In lakeside wetland Napahai of northwest Yunnan Plateau, wetlands degradation was mainly caused by three types of human disturbance, including cutting off water supply, overgrazing and hogging. Based on the field survey of wetland ecological characteristics and environmental quality, eighteen degraded wetland plots were set up along the three human disturbance gradients on Napahai wetland area in 2011. The degradation characteristics of wetland vegetation and soil as well as the associated key ecological factors were investigated in the present paper. Among the three types human disturbance, the number of wetland plant community diversity, richness, number of species, Shannon-Wiener index, important value (IV) of helophyte plant and soil characteristics including organic matter, total nitrogen, available nitrogen, water content and porosity were highest in cutting off water supply, followed by overgrazing and lowest in hogging, whereas the order was opposite for soil bulk density, total potassium. The lowest community height was observed in hogging disturbance. The eighteen typical wetland plots were classified into five types by TWINSPAN, including primary wetland, lightly degraded wetland, moderately degraded wetland,severely degraded wetland and extremely degraded wetland. Pearson correlation analysis showed that water content was significantly and negatively correlated to bulk density and organic matter was positively correlated to total nitrogen among these three transects. The rest of indexes correlation varied greatly under different human disturbance among transects, which means human disturbance has seriously changed the soil physicochemical properties, especially hogging. CCA analysis was employed to test the effect of soil physicochemical factors on Ⅳ of plant species, which involved thirty-eight species variables and eleven soil variables. The correlation coefficient between vegetation characteristics and soil physicochemical properties was above 0.950, with the first two axis eigenvalue 0.811 and 0.613, respectively. The CCA results showed that plant community composition of Napahai lakeside degraded wetland was positively correlated to soil water content and negatively correlated to soil total phosphorus content. The soil degradation index was used to reflect the degree of soil degradation, with the primary wetland plot as reference. Then soil degradation index was-7.40%,-14.53%,-45.01% for cutting off water supply, overgrazing and hogging transects, respectively. This suggests that the soil was seriously degraded under human disturbance, especially hogging disturbance. Through analyses of TWINSPAN classification, soil degradation index, the change of plant community characteristic and soil physicochemical properties, degradation of wetland vegetation and soil in Napahai lakeside wetland were simultaneously dominated by three types disturbance, the order of human disturbance degree was hogging, overgrazing, cutting off water supply. Soil water content and total phosphorus content were the driven forces that caused the wetland degradation in Napahai lakeside wetland. Understanding driving factors of wetland degradation is a key step towards wetland ecosystems restoration and biodiversity conservation. Different intensity and type of human disturbance have different ecological influences on plant community characteristic, soil physicochemical properties and their interrelation. Therefore, comparing the effects among different human disturbances on the wetland plant community characteristics and soil properties can provide a theoretical basis for reasonable utilization and restoration of Napahai wetland. 参考文献 相似文献 引证文献