Evaluating the landscape ecological risk based on GIS: A case‐study in the Poyang Lake region of China

Abstract

Influenced by human activities, the largest freshwater lake in China, Poyang Lake is suffering from landscape degradation and increased ecological risks. However, the specific landscape ecological risk in Poyang Lake region remains unknown. The impact of land use change on landscape pattern and ecological risk around Poyang Lake has not been revealed. In order to analyze the spatio-temporal distribution characteristics of landscape ecological risk in Poyang Lake region, this study constructed a landscape ecological risk index model based on GIS, geostatistics, and landscape ecology theory. The results show that: (a) all land use types in Poyang Lake region had been changed during the period 2010-2018. While large tracts of farmland and woodland were converted into construction land, farmland and woodland have seen the largest decrease and construction land has increased greatly. (b) On the whole, the low and medium-low landscape ecological risk area accounted for about 60% of the total area, while high and medium-high risk area increased during 2010-2018. The landscape ecological risk has seen a downward trend with increased low and medium-low ecological risk areas during 2010-2018. Spatially, ecological risk in the core waters of Poyang Lake was higher, while in the surrounding waters was lower. (c) The landscape ecological risk in Poyang Lake Region in each period shown positive spatial correlation and tended to be spatially agglomerative. The high-high risk clusters were mainly located in the core waters of the Lake area, while the low-low risk clusters were mainly located far away from the core waters, including county and city areas. (d) In 2018, farmland, woodland, grassland, and unutilized land were dominated by medium and medium low risk, the landscape ecological risk in the water area was the highest, and that of construction land was the lowest. The decrease rate of ERI in water areas was the largest, indicating that the change of water area contributed the most to the reduction of landscape ecological risk. During the process of ecological risk management in Poyang Lake Region, attention should be paid to the changes of the water area's structure and quality.

Landscape Pattern and Ecological Risk Assessment in Guangxi Based on Land Use Change

“…Currently, development of ecological risk assessment models based on land-use changes is a research hotspot [26]. For example, Xie et al [27] analyzed ecological risks associated with landscape patterns within the region of Poyang Lake from 2010 to 2018 and ranked landscape pattern risks in descending order as watershed, construction land, unused land, woodland, grassland, and arable land. As another example, Zhang et al [28] analyzed land-use changes and dynamic characteristics of coastal cities in China using a land-use transfer matrix and other tools so as to further analyze the impact of land-use changes on landscape ecological risks.…”

Variations of Habitat Quality and Ecological Risk and Their Correlations With Landscape Metrics in a Robust Human Disturbed Coastal Region

“…From the perspective of landscape structure of regional ecosystem, ecological risk at the landscape level was assessed with the area proportion of the respective landscape component, landscape structure index and landscape fragility index (Wang et al, 2020;Xie et al, 2021).…”

Identifying Terrestrial Landscape Character Types in China

“…Meanwhile, SHDI and SHEI characterised the degree of heterogeneity and uniform distribution of the landscape, providing a thorough understanding of landscape diversity in the region. Considering that scale changes have different degrees of influence on the results of quantitative analysis of spatial structures [39,42,43], semivariograms are widely used to study landscape pattern scales [44][45][46][47]. Therefore, we used a semivariogram to identify the suitable study scales.…”