基于生态足迹模型的网湖流域生态环境评价

网湖流域是黄石市阳新县重要的河流集水区之一。本文基于生态足迹模型对网湖流域1980年、1990年、2000年、2010年和2018年的土地类型面积、人均生态足迹、人均生态承载力、生态盈亏的演变进行了评估。结果表明:耕地面积与水域面积变化呈现此消彼长的演变特征;1980~2018年网湖流域人均生态足迹先增后减,人均生态承载力逐渐下降;1980~2018网湖流域生态盈亏呈现“盈余–赤字–盈余–赤字”波动变化的趋势,可能表明网湖流域正在经历退化阶段。因此,在开展网湖流域生态治理和水资源利用管理工作时,需要合理规划、科学开发,确保流域生态系统的稳定和可持续发展。The Net Lake watershed is one of the important river catchments in Yangxin County, Huangshi City. This paper evaluates the evolution of land type area, per capita ecological footprint, per capita eco- logical carrying capacity, ecological surplus and deficit of the Net Lake watershed in 1980, 1990, 2000, 2010 and 2018 based on the ecological footprint model. The results show that: the changes in cultivated land area and watershed area show the evolution of this and that;the per capita ecologi- cal footprint of the Nettle Lake Basin increased and then decreased, and the per capita ecological carrying capacity gradually decreased from 1980 to 2018;the ecological surplus and deficit of the Nettle Lake Basin from 1980 to 2018 show the “deficit” and “surplus”. The fluctuating trend of “deficit- surplus-deficit-surplus” from 1980 to 2018 may indicate that the net lake basin is experiencing a degradation stage. Therefore, when carrying out the management of ecological management and water resources utilization in the Net Lake Basin, it is necessary to carry out rational planning and scientific development to ensure the stability and sustainable development of the basin ecosystem.

Relationship Between Changes of River-lake Networks and Water Levels in Typical Regions of Taihu Lake Basin,China

The typical regions of the Taihu Lake Basin,China,were selected to analyze the variation characteristics of river-lake networks under intensive human activities.The characteristics of the fractal dimension of river networks and lakes for different periods were investigated and the influences of river system evolution on water level changes were further explored through the comparison of their fractal characters.The results are as follows:1) River network development of the study area is becoming more monotonous and more simple;the number of lakes is reducing significantly,and the water surface ratio has dropped significantly since the 1980s.2) The box dimension of the river networks in all the cities of the study area decreased slowly from the 1960s to the 1980s,while the decrease was significant from the 1980s to the 2000s.The variations of lake correlation dimension are similar to those of the river network box dimensions.This is unfavorable for the storage capacity of the river networks and lakes.3) The Hurst exponents of water levels were all between 0.5 and 1.0 from the 1960s to the 1980s,while decreased in the 2000s,indicating the decline in persistence and increase in the complexity of water level series.The paper draws a conclusion that the relationship between the fractal dimension of river-lake networks and the Hurst exponents of the water level series can reveal the impacts of river system changes on flood disasters to some extent:the disappearance of river networks and lakes will increase the possibility of flood occurrence.