Spatial and temporal distribution of land use pattern change in Songnen high plain

Abstract: Land use pattern can affect regional ecological environment, and it is important for diagnosing if regional land use is reasonable. Land use pattern is an important element to analyze and explain spatial phenomenon, process and mechanism of regional land use. This research took Bayan County as the study area to solve the problem that the social and economic attributes of land use pattern did not consider spatial characteristics to make up for deficiencies of comparative analysis of a variety of social and economic attributes of land use pattern in space by using Tupu analysis. To reveal the spatial and temporal distribution characteristics and its differentiation of land use pattern change in the study area from 1979 to 2015, comprehensive dynamic degree of land use in different periods (1979-1991, 1991-2003 and 2003-2015) was estimated, land use intensity and land use diversity degree at different time points in the years (1979, 1991, 2003 and 2015) were calculated and land use information Tupu in semi-variogram was set up by using geographic information system and remote sensing technology and Matlab programming. The conclusions included: 1) Structure factors, random factors and the interaction of structure factors and random factors caused the spatial heterogeneity of comprehensive dynamic degree, land use intensity and land use diversity degree. The land utilization procedure was not only affected by natural factors and human interferences, but the effects were different. Comprehensive dynamic degree of land use was mainly influenced by natural factors from 1979 to 1991 in study area. Comprehensive dynamic degree of land use was influenced by natural factors and human interferences from 1991 to 2003 in study area. Comprehensive dynamic degree of land use was common affected by natural factors and human interferences, and the human interferences had a deeper influence. Land use intensity was mainly influenced by natural factors in 1979 and 1991 and by natural factors and human interferences in 2003 and 2015. 2) The rate of land use change showed obvious differences from 1979 to 2015. The comprehensive dynamic degree of land use presented a declining trend in different periods during 1979-1991, 1991-2003 and 2003-2015. The average of comprehensive dynamic degree of land use was 1.12%, 1.11% and 0.85%, respectively. The comprehensive dynamic degree of land use was relatively high in the administrative boundaries; and 3) The land use intensity presented an increasing trend in study area in 1979, 1991, 2003 and 2015. The average value of land use intensity was 3.66, 3.68, 3.76 and 3.82, respectively. The land use diversity degree presented a declining trend in study area in 1979, 1991, 2003 and 2015. The average value of land use diversity degree was 0.29, 0.28, 0.27 and 0.26, respectively. The higher the land use intensity was, and the lower the land use diversity degree was, which indicated there was a conflict between the distribution of land use intensity and the distribution of land use diversity degree. The results of this research would improve the regional ecological environment. Besides, it also had theoretical and practical significance to achieve regional sustainable land use.