Analyzing on the spatial-temporal pattern of land-use change in Maduo County of the riverhead area of the Yellow River

In order to provide scientific basis for ecological environmental protection and construction in source area of Yellow River,supported by the technique of GIS,the spatial-temporal pattern characters of LUCC in Maduo County from 1985 to 2000 were analyzed based on Landsat TM digital data.Some significant findings were obtained.Though LUCC in Maduo County kept steady with slight change,the changing characters in the two research period of time(1985-1995 and 1995-2000) were obviously different,and especially,the converting of mid-coverage pasture and low-coverage pasture showed the characters of huge numbers and rotation.During the period of 1985-1995,the land-use transforming mainly occurred between thin woodland and low-cover grassland,low-cover grassland and non-used land,as well as within the range of grassland,accounting generally for 93.03% of the total transformed amount;conversion amount from mid-cover grassland to low-cover grassland and from grassland to non-used land accounts respectively for 26.14% and 18.99% of the total conversion amounts;all the thin woodland had been converted into low-cover grassland.The conversion characters mentioned above showed that the environment in Maduo County from 1985 to 1995 degraded badly.During the period of 1995-2000,the conversion amount between grassland and non-used land accounted generally for 97.26% of the total conversion amount.The net change from non-used land to low overlay degree grassland and from low-cover degree grassland to mid-cover grassland accounts respectively for 18.15% and 27.46% of the total conversion amounts.The above characters show that environmental protection in Maduo County has succeeded originally.During the two periods of 1985-1995 and 1995-2000,land-use conversion obviously occurred in the eastern and middle districts of Maduo County.