| As the research on global environment variation has been going to depth, more and more evidences indicate that the Earth's climate gets warmer and warmer. How does wetlands, as the most sensitive part of the Earth system, responds to climate changes? The researches on the climate warming effects of wetlands ecosystem were extensive in domestic and abroad, it is sure that global warming caused a certain ecologic influence on ecological system in wetlands. Then for Zhalong wetlands, how to respond? Here, based on the evidence for land use and climate changes in Zhalong wetlands-Landsat TM images during 1979-2006 and daily meteorological data during 1960-2006, "3S" techniques, landscape ecology theory and climate statistical method were used to study the characteristics of climate changes during recent 46 years and the spatial pattern, the combination characteristic and the dynamic changes of LUCC in Zhalong wetlands, and the impact and response of climate change on land use and land cover change were discussed from the spatial and temporal scale to reveal the change condition of the landscape pattern and the major driving factors of climate changes, as a basis for the research on assessment of sustainable development in Zhalong wetlands. This study was scientific reference for achieving sustainable use of land resources and socio-economic sustainable development in Zhalong wetlands, the main conclusions were as follows:(1)The results of the dynamic change of LUCC showed that in Zhalong wetlands, marshland and grassland were the substrate landscape type. During the period of 1979-1989, 1989-1999 and 1999-2006, the area of farmland increased in different degrees, the area of marshland has been shrinked dramatically at the beginning of this century, during the whole period of 1979-2006, bareland declined significantly.During the period of 1979-2006, the transformation between each land cover types in Zhalong wetlands mainly represented that marshland transformed to grassland and farmland, grassland transformed to farmland and bareland transformed to grassland and farmland. It was obvious distribution in the core area of wetlands that the region of marshland transformed to grassland, which indicated that the degradation of wetlands has deepened to the core area.The analysis of the centrobaric migration of land cover types showed, in lately 30 years, migration directionin of marshland, farmland, grassland and bareland was northeast in Zhalong wetlands. As the substrate landscape type, migration directionin of marshland and grassland showed that the core area of Zhalong wetlands drifted to the north.Consequently, it could be speculated that the migration trend in the core area might be the response of the regional climate warming trend. With the constant development of land, from the 1970s to the beginning of this century, integrated index of land use degree was growing in Zhalong wetlands. Land use intensity of the counties within Zhalong wetlands were gradually increased. In addition to Tailai county, the highest level of land use intensity appeared in the beginning of this century. On the whole, the area of the farmland of Zhalong wetlands had increased and bareland had decreased, the change of Fuyu county was sharpest and Dumeng county, respectively. It was also assumed that, on account of the opposite trends between farmland and bareland, the occupier of the bare ground has become fact that could not be ignored.(2)The analysis results of the landscape pattern dynamic of land use of Zhalong wetlands showed that during 1980s~1990s, the patches quantity of various landscape types substantially increased in both,the degree of landscape fragmentation of these reached its height,due to low inter-connect between adjacent patches, patches tended to dispersed and fragmented. In 21st century, NP/CAof various landscape types showed a downward trend, the evidents of rising dominance index of farmland and gradual weakening of bareland and grassland lead to the equalization of landscape pattern since 1980s. In the late of 1990s, the fragmentation and dominance of marshland had reached the highest level. For the significant reduction of scattered marshland patches area in wetlands fringe, patches with higher connecting levels of the core area retained.Since 2001, the government repeatedly compensating water for Zhalong wetlands and strengthenning supervision may lead to the largest patch index rise and landscape shape index decrease, which, to some extent,alleviated the fragmentation trend of the marshland,but the reality of wetlands degradation was still grim.From the 1970s to the beginning of this century, the rising of landscape diversity index, evenness index, landscape shape index and perimeter area fractal dimension indicated the growing irregulation of landscape shape, the growing diversification and homogenization of land use change tend and the growing complicate landscape pattern.(3) During the period of 1960-2006, the analysis results of climate change showed that,in Zhalong wetlands, annual average temperature,annual minimum temperature, annual maximum temperature and annual accumulated temperature≥10℃rose significantly, in lately 46 years,showing a strong warming trend. The statistically significant mutation of annual average temperature occurred in 1988. The annual average temperature,annual minimum temperature and annual accumulated temperature≥10℃was warming significantly since the 1990's. The fluctuation periods(2-6a) of the annual average temperature,minimum temperature,maximum temperature and annual accumulated temperature≥10℃were statistically significant.In recent 46a, in Zhalong wetlands,the general trend of annual precipitation, annual moderate precipitation and annual heavy precipitation showed fall and the mutation trend of these was weaker. During the period of 1960s-1970s and the beginning of this century, precipitation was less than normal. Annual precipitation, annual moderate precipitation and annual heavy precipitation switched frequently between high and low in 2-4a scale.Annual relative humidity of Zhalong wetlands showed a downward trend in lately 46a. The mutation that occurred in 1995 reached a significant level. The periodic vibration signal of annual relative humidity in 2a time scale was strongest, the partial dry period of that hold the dominant position in the whole time.In Zhalong wetlands, the spatial difference of annual average temperature was from southwest to northeast, that was to say, the southwest was higher, the northeast was lower. Compared with annual average temperature, the spatial pattern of annual precipitation and annual relative humidity were to the contrary.After 1988 of the mutant year, the frequency and intensity of hot summer and warm winter events had conspicuous increased and atmospheric moisture had declined since the mid of 1980s, which showed that there was the warm-dry direction in climate trend in Zhalong wetlands.(4)The analysis results of canonical correlation between land use landscape dynamics and climate change showed that, in Zhalong wetlands, the index of patches area had significant representation in the farmland,marshland, lake and bareland, the typical climate factors corresponding to the different land use types were the annual minimum temperature, annual maximum temperature, annual accumulated temperature≥10℃and annual relative humidity. The joint outcome in the annual temperature, annual precipitation and annual relative humidity lead to the complex landscape pattern of grassland.In terms of the residuals, there were statistically significant correlations between typical factor of every land use types and annual minimum temperature. Periodic characteristics of land use dynamics and climate change in farmland, marshland, grassland, landscape scale were not significant. 10-year fluctuations in dynamics change of lake and bareland 9-year fluctuations in annual minimum temperature.In recent 30 years, correlations between land use pattern changes of marshland, lake and climate change were strongest, followed by farmland and grassland, bareland was weakest in Zhalong wetlands. It was also assumed that the contraction trend of marshland and grassland responded to warm-dry climate trend to a certain extent. On the weak correlation between bareland and climate change, the acts of earning a living, vigorously cultivating land and overgrazing in population pressure were likely to result in drastical reduction of bareland within the wetland. The above results suggested that land use landscape dynamic changes was caused by the interaction of climate factors and human activities in both.(5)Based on the study of sustainable development theory, this paper constructed the sustainable development indicator system for Zhalong wetlands nature reserve, then analysed the level of sustainable development of the three subsystem of social-economic-resource and environment application of projection pursuit method in Zhalong wetlands. It confirmed that it was not satisfactorily coordinated for the level of interregional sustainable development in Zhalong wetlands, resources and environmental sustainability status showed a worse trend. The limits of population and resources environment to the sustainable development in wetlands were the most prominent. The papers put forward practically five recommendations against wetlands resources and environmental protection which provide a theoretical reference for achieving sustainable use of land resources and socio-economic sustainable development in Zhalong wetlands.
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