| Describing and understanding spatial patterns over time is an important research area in landscape ecology. The forest-steppe ecotone with alkalized grassland in Hulunbeir, which borders the Great Xing'an forest region, is one of the most significant ecological barriers in North China. In the last decades, due to the changes of global climate and the general impacts of human activities, timberline in the transition region moved up, vegetation deteriorated, grassland changed into desert and the water and soil lost drastically. It is also an area suffers from most acute human activities. All these factors, in combination, severely constrain the sustainable development of local resource, environment, economy and society. Nowadays, researches on dynamic changes of landscape structure and function characteristics to be also few. The direction, speeds of landscape dynamic changes, these questions need a systematic research.By integrating Remote Sensing (RS) and Geographic Information System (GIS), The spatial information of landscape pattern of ecotone between forest and grass in Hulunbeier from three periods which are 1995, 2000 and 2005 is explained and extracted. this paper explores how and why the landscape pattern changed, based on the basic theory and method of landscape ecology, taking fractal dimension, isolation and dominance as indexes to analyze the spatial-temporal dynamic changes of the landscape pattern. And using the Markov Chain model to predict the changes of landscape patterns in future. The results shows:.(1) From 1988 to 2005, it is remarkable to interchange between different landscapes, especially frequently among forest land, grassland, cropland and unused land. The area of forest land has decreased sharply by 7858 km2, the max dynamic degree amount to 1.89, while the unused land increased 4087 km2, and the max dynamic degree of amount to 14.91. the centroid of main landscape types had moved east, the centroid of forest has moved 4.5 km southeast, while the centroid of grassland moved 29.9 km northeast.(2) Indices of landscape characteristics have changed significantly from 1988 to 2005, with the landscape diversity index and fragmentation index increasing and the landscape dominance index decreasing. Main landscape types including forest, grassland, cropland, unused land show their patches quantity added and patch shape changed more and more complexly. And the characters of landscape sustainability analysis shows the trend will be continue.(3) Through the research of terrain factor differentiation of landscape pattern in Hulunbeier forest-grassland ecotone, it is fond that:With the changes of altitude, aspect and slope, the landscape pattern is also experiencing regular changes, and the impacts are various form different terrain-grade level, which presents a significant distribution. The main landscape types distributed to altitude 400~1200m and slope≤25°.(4) Using the Markov Chain model to predict the changes of landscape pattern in future. The results shows are as followings: By 2020, under the influence of a series of environment factors, primarily human activities, grassland landscape type reduces the most area as well as forest land, which proportion in the entire area decrease from 41.20 percent in 1995 to 32.53 percent, and the reduced area was mainly transformed to Cultivated land and Unused land. By then, the two landscape types may respectively amount to 7.573% and 6.132% in total area of the ecotone.This study revealed the intensities, directions, and rates of landscape pattern changes, and the relationships among landscape pattern, ecological processes, and human activities. This study can provide scientific basis for the sustainable development of the ecotone.
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