Characterizing the changes in landscape structure in the Lake Kasumigaura Basin, Japan using a high-quality GIS dataset

Abstract

The changing characteristics of landscape structure in the Lake Kusumigaura Basin, Japan from 1979 to 1996 were investigated using time-series high-quality GIS datasets. We used FRAGSTATS software to calculate landscape indices to characterize the landscape structure. We found that human-modified landscapes, such as artificial fields and golf courses, increased rapidly during the study period, while forests and croplands decreased rapidly in the same period. From 1979 to 1996, forestland decreased by 8.4%, in which 44% turned into artificial fields, 37.6% turned into golf courses, and 6.8%, 6.4%, and 4.1%, turned into plowed fields, residential areas, and urban areas, respectively. Increased patch number and decreased mean patch area indicated that the most significant characteristic of land use/cover change in the Lake Kusumigaura Basin is the fragmentation of the landscape. Both Shannon's diversity and Shannon's evenness indices increased considerably during the study period, also suggesting the landscapes in the study area became more fragmented and heterogeneous. This fragmentation trend is most likely to continue due to the increasing population in the Lake Kusumigaura Basin in recent years.