Analysis of dynamic changes in land use based on landscape metrics in Nagasaki, Japan

Abstract

Land use changes are a reflection of the effects of human activity on Earth’s ecosystems. Land use in Nagasaki has changed significantly in recent years with built-up land area increasing from 34 to 62 km2 during the study period (1976 to 2009). Landscape metrics are quantitative indexes that can streamline landscape pattern information and reflect its characteristic structural composition and spatial configuration. Using patches as landscape elements, 12 landscape metrics at two levels (class and landscape levels) were selected to analyze the dynamic changes in land use. At the class level, the following observations were made: (1) merger development of most land use types; (2) a trend toward merging and extension of built-up land and forest; and (3) land use types dominated by nature showed higher shape complexity and lower uniformity in patch area distribution than land use types dominated by human activities. At the landscape level, the results showed an increasing degree of fragmentation and decreasing degree of patch shape complexity in the study period. The study is the first analysis to be done on this scale in Nagasaki that showed the change characteristics in land use by landscape metrics.