Research on Land Use Changes and Ecological Risk Assessment in Yongjiang River Basin in Zhejiang Province, China

Abstract

Studying land use changes and ecological risk assessment in Yongjiang River Basin in Zhejiang Province, China, provides theoretical references for optimal configuration of land resources and maintaining stability of ecosystems. Given impacts of land use changes on landscape patterns in the Yongjiang River Basin, ecological risk assessment indexes were constructed and used to analyze temporal and spatial variation characteristics of ecological risk within different periods. Results show that (1) the construction land area was increased quickly, while the cultivated area decreased sharply. A prominent characteristic of land use changes was manifested by transforming cultivated area and forestland into construction land. The utilized degree of the land increased continuously. Spatially, the land utilized degree in northern regions was higher than that in southern regions and the degree in eastern regions was higher than that in western regions. (2) The ecological risk in the Yongjiang River Basin was intensified and the area of high ecological risk was expanded by 893.96 km2. Regions with low and relatively low ecological risks concentrated in western and southern regions of the Basin, whereas regions with high ecological risks were mainly in northern and eastern regions. Landscapes in cities and towns at a high economic development level are highly sensitive to human activities. (3) Transformation of ecological risk is complicated. Land area with the ecological risk changing from a low level to a high level was 4.15 times that with the ecological risk changing from a high level to a low level. There were 15 transformation directions among different ecological risk regions.

Spatial–Temporal Evolution and Correlation Analysis of Ecosystem Service Value and Landscape Ecological Risk in Wuhu City

“…Referring to previous relevant studies [32,40], combining the actual situation of the study area and the range of ERI in each sampling plot, ecological risk is divided into 5 grades by the natural break point method using ArcGIS 10.2: 0.013 < low ERI ≤ 0.016, 0.016 < relatively low ERI ≤ 0.019, 0.019 < medium ERI ≤ 0.023, 0.023 < relatively high ERI ≤ 0.030, and high ERI > 0.030 ( Figure 4). The spatial pattern distribution and area variation of the ecological risk in Wuhu city in the three periods are shown in Figure 4 and Table 7.…”

Evaluating Land Use and Land Cover Change in the Gaborone Dam Catchment, Botswana, from 1984–2015 Using GIS and Remote Sensing

“…Overall accuracy = u a=1 C aa Q × 100 (5) where C aU is the total number of correct classifications of a particular map class; C a+U is the total number of pixels classified in a particular map class; C aR is the number of reference points classified accurately, while C a+R is the total number of reference points for that particular map class. Furthermore, Kappa analysis was carried out.…”

“…These changes take place temporally at different times such as a few months or years and spatially such as the extent of area and the intensity of land use [3]. In view of this, the long-term changes are probably the most significant processes for global environmental change [4] and are useful for evaluating the sustainability of natural resources [5]. The natural and anthropogenic factors are identified as drivers of LULC change [6][7][8][9].…”

Spatiotemporal Evolution of Landscape Ecological Risk Based on Geomorphological Regionalization during 1980–2017: A Case Study of Shaanxi Province, China

“…The beginning of the "Anthropocene" is reflected by changes in global landscape patterns and ecological functions [3] and this new period is related to the multi-directional evolution of the ecological environment and has generated many ecological risks. The assessment and prevention of ecological risk has become a popular research topic in geography and ecology in response to the comprehensive management of social ecosystems [4][5][6][7][8].…”