Research On Spatio-temporal Evolutions Of Land Use Pattern In Dianchi Basin Based On GIS

The spatio-temporal evolution of land use pattern is one of the bases and key points for the study of Land Use / Cover Change(LUCC).Based Landsat TM in 2000,2007 and Landsat8 OLI in 2014 as remote data sources,the distribution pattern of land use pattern in three periods was obtained research area of Dianchi Basin through both visual interpretation and supervised classification.We took analyzed the overall land use dynamic changes and terrain gradient effects of Dianchi Basin by the use of land use model and terrain gradient.In order to more clearly reveal the spatial and temporal patterns of land use change,we introduced geo information spectrum principle from the geo-information science,and constructed of the main spectrum,"rise" and "fall" spectrum and spectrum of land use change pattern,and more discussed the dynamic trajectory change of the pattern and process from the perspective of the spatio-temporal change and the terrain gradient in 2000-2014 years,in order to provide the optimal allocation of land use and sustainable development of land resources for the planning and environmental protection departments of Kunming city.The main results and conclusions included:(1)The main performance of Dianchi Basin land use dynamic change in 2000-2014 year includes that cultivated land and grassland was converted in construction land and forest land,the distribution range of land use showed respectively that grassland changed from down to stable,cultivated land reduced over time,construction land and forest land expanded and water area and unused land were basically unchanged;the dynamic degree of land use showed that cultivated land and grassland decreased,forest land and construction land increased,water and unused land dynamic was basically unchanged;the land use change was stronger development degree and certain development potential,but the shrinking difference of degree of land use change quantity and rate didn't bring out enough land resources potential to exploit.(2)There are different distribution advantages of land use change pattern in different terrain gradient in the Dianchi Basin in 2000-2014 year.with the terrain gradient increased,the distribution advantages of water area,construction and cultivated land,forest land concentrated in the lowest,low and mid-low,mid-high and high terrain gradient,their change trend were respectively down to flat,increased rapidly at first and then decreased slowly,firstly increased and then tended to be stable;the grass distribution advantage indented to low terrain gradient,but unused land expanded to mid-high and high terrain gradient,their change trend were both first increasing and then diverse because of their strong adaptability.(3)The main Geo-map transformation of land use of Dianchi Basin is as follows: grassland were occupied by woodland and cultivated land,construction land expanded by reducing cultivated land,the mainly interchanged were between grassland and cultivated land,between cultivated land and construction land(woodland),between construction land and grassland(woodland).In the "rising trend" Geo-map,the new-increased proportion of woodland,cultivated land and unused land decreased in Dianchi Basin,and their spatial distribution gradually decreased.The new increased proportion of grassland and construction increased,and the water area remained unchanged.In the "falling potential" Geo-map,the new-reduced proportion of grassland was reduced and the new-reduced proportion of cultivated land,woodland and construction land were increased,and the water and unused land were almost invariable.In the pattern map,the Geo-pattern map of land use change is mostly stable-unchanged type and prophase change type,accounted for 62.57% of the total area,and their aggregation is obvious sheet and strip distribution.The main stable-unchanged types of “woodland?woodland?woodland” and “water area?water area?water area” located in the Dianchi Basin surrounding high altitude region and Dianchi lake;the prophase change types of “cultivated land?construction land?construction land?construction-land” and “grassland?woodland ?woodland” were mainly distributed type,around the basin of high altitude area and downtown area of Kunming city.(4)The Geo-pattern map of land use change of Dianchi Basin in the 2000-2014 shows different vertical hierarchy on different terrain gradients.The maximum map of stable-unchanged type “water area?water area?water area”,“construction land?construction land?construction land”,and “woodland?woodland?woodland” had respectively distribution superiority mainly in low,mid-high and high terrain gradient,the maximum map of prophase change type “grassland?woodland ?woodland” had distribution superiority in mid-low and mid-high terrain gradient,the maximum map of anaphase change type “cultivated land?cultivated land? construction land",repeated change type “construction land?cultivated land ?construction land”,continuous change type “grassland? cultivated land ?construction land” had all distribution superiority in low and mid-low terrain gradient.