Analysis of Lake Shoreline Evolution Characteristics Based on Object Increments

Abstract

Evolutionary changes in shallow lake shorelines can significantly impact wetland biodiversity transformation. This paper aims to further elucidate the wetland evolution process by investigating the temporal and spatial characteristics and rules governing lake shoreline evolution. Departing from traditional analyses of wetland area and shoreline length changes, this paper presents a comprehensive approach to quantifying typical lake shoreline evolution patterns using the concept of object increments. These evolutionary patterns are classified into four types: “expansion”, “shrinkage”, “appearance”, and “disappearance”. Using Shengjin Lake as a case study, Landsat images from 2001 to 2020 were used to extract the lake shoreline. The temporal series characteristics of different evolution patterns, the laws at the patch scale, and the characteristics of evolution direction were analyzed. The key findings are as follows. (1) The evolution of Shengjin Lake’s shoreline from 2001 to 2020 was primarily characterized by “expansion” or “shrinkage” patterns with a clear negative correlation between them. The “appearance” and “disappearance” of lake shorelines were rare. (2) The evolutionary patterns of “expansion” or “shrinkage” mainly occurred in smaller patches with a large number, while the “appearance” and “disappearance” of lake shorelines occurred mostly in larger patches with a small number, and there were no occurrences in certain years. (3) The “expansion” evolutionary pattern was more dominant in the northeast and east-by-northeast regions, while the “shrinkage” evolutionary pattern varied across the southwest and west-by-southwest regions. In conclusion, the analysis of shoreline evolution’s temporal and spatial characteristics, based on spatiotemporal object increments, can quantitatively elucidate the lake wetland evolution process and offers a novel perspective for future research on lake wetlands.