Spatial-temporal variations of landscape pattern and hot spot analysis in the Lixiahe Plain of Jiangsu Province from 1980 to 2018

Abstract

Objective With an exploration of the temporal and spatial changes of landscape pattern as well as an investigation of its cold and hot spots, this paper is aimed to provide a scientific basis for regional ecological security and high-quality development. Method With landscape type data collected of the Lixiahe Plain, Jiangsu Province over the five periods of 1980, 1990, 2000, 2010 and 2018, an analysis was made of the characteristics of temporal and spatial changes of its landscape pattern in the past 40 years using landscape pattern metrics, transfer matrix and comprehensive dynamic index. Then, an investigation was conducted of the cold and hot spot regions of landscape changes on the basis of hot spot analysis. Result Cultivated land, lake wetland and construction land were the dominant landscape types in the study area with the coverage of cultivated land accounting for the largest proportion, but having decreased by 1 000.67 km2 in the past 40 years whereas the areas of lake wetland and construction land increasingly expanded, with the area of construction land increasing by 679.83 km2 and the area of grassland and unused land showed a slightly decreasing trend, while that of forest increased slightly. The landscape types had undergone complex mutual transformations in the past 40 years with those of cultivated land, lake wetland and construction land being the most remarkable with the comprehensive dynamic index of the grid landscape varying between 0 and 5.43% over the study period. The landscape change of the Lixiahe Plain had obvious directionality and agglomeration: the center of change was tilted along the “southeast-northwest” direction, and the hot spots of landscape change were located at Xinghua City, Gaoyou City, Yandu District and Jiangdu District. Conclusion The landscape pattern of the Lixiahe Plain underwent significant changes due to the increase of landscape diversity and the intensification of fragmentation and the impact of human activities on the landscape pattern. The implementation of the natural wetland restoration policy had a positive impact on the landscape ecological security in the Lixiahe Plain. [Ch, 4 fig. 4 tab. 32 ref.]