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After randomizing the input information of age and distribution of forest species we simulated the long-term(2500 years) dynamic of forest landscape pattern of huzhong area in Great Xing′an Mountains using spatially explicit landscape model(LANDIS),Then we took the period when simulation results reached stable as the time range to estimate the historical range of variability(HRV).Furthermore,we analyzed the relationship between HRV and the forest landscape pattern of 1990 and 2000 using principal component analysis and kernel density estimation methods.The simulation results showed that the succession of almost all forest species arrived to their stable status at around 900th year of the simulation,and the period afterwards was utilized to estimate the HRV;as to the characteristics of forest,landscape pattern in 1990 fell out of the HRV in area of patches and the degree of landscape fragmentation,especially mature and over-mature forest deviated significantly from HRV in patch area and fragmentation;though forest harvest management was better planned after 1990,the forest landscape pattern in 2000 still deviated from the HRV.

Northeastern China is one of the regions that would be mostly affected by the changing climates,and created the particular climate pattern and characteristics under climate changes.The pattern and characteristics of climate changes in Northeastern China was analyzed with the methods of the linear regression method,cumulative anomaly method,Mann-Kendall test method and Morlet wavelets analysis method based on daily average air temperature and daily precipitation data observed at 96 meteorological stations covered the Northeastern China from 1961 to 2005.The linear regression method was used to study the variation trends of mean temperature and precipitation on annual-scale and seasonal-scale in recent 45 years.The cumulative anomaly method and Mann-Kendall test method were used to test trends and abrupt changes of annual mean temperature and precipitation.The Morlet wavelet analysis method was used to detect the change interval of annual mean temperature and precipitation.The linear trend rates for annual and seasonal mean temperature and annual and seasonal precipitation were calculated at each meteorological station.Those rates were then interpolated using inverse distance weighted(IDW) interpolation to reveal their spatial distributions.The results showed that the climate in this region showed a significant warming trend,the annual mean temperature varied between 2.45 ℃ and 5.72 ℃,and the annual mean temperature has increased by 0.38 ℃/10 a(P0.01) in recent 45 years,and an abrupt change from low temperature to high temperature occurred in 1988—1989.In addition,all of the seasonal temperatures showed increasing trends,and the increase of temperature in winter were higher(0.53 ℃/10 a) than in the summer(0.24 ℃/10 a).The decade change of annual and seasonal mean temperature also showed spatially increasing trends and the higher the latitude,the more obvious the increasing trend.The calefactive range was larger in the northern Da Hinggan Mountains and Xiao Hinggan Mountains,and it was smaller in the Liaohe Plain,Liaodong Peninsula and southern Changbai Mountain.The annual precipitation varied between 430.40 mm and 678.72 mm,and the annual precipitation showed a decrease trend in recent 45 years,and decreased by 5.71 mm/10 a(P0.05),the precipitation in 1980s was more than in the other decades,and the abrupt change in precipitation occurred during in 1982—1983.The seasonal precipitation showed various trends,the spring precipitation and winter precipitation showed increasing trend,but the summer precipitation and autumn precipitation showed decreasing trend.The Liaodong Peninsula and southern Changbai Mountain showed significantly decreasing trend in precipitation,whereas,the northern Da Hinggan Mountains and Songnen Plain showed obviously increasing trend.The climate change interval analysis revealed that the annual mean temperature fluctuated significantly with the interval of 11 years,24 years and 6 years,and the annual mean precipitation fluctuated with interval of 16 years and 6 years,respectively.For this region,the climate was trended to be warmer and dryer in recent 45 years and the temperature and the precipitation showed different interval.

To explore the variation law of architectural landscape is important for forecasting the variation in urban landscape in the process of urban renewal.It was mainly studied the evolution law of architectural landscape and spatial distribution features of building transformation in the Tiexi District,Shenyang,China,during the urban renewal process in this paper. In this article,the three-dimensional information of buildings in the Tiexi District was extracted from aerial photos(1997) and QuickBird imageries(2002,2005 and 2008) based on ArcGIS,Erdas and Barista software.We divided the buildings into five types as Residential building,Industrial building,Commercial building,Educational and Medical building,and Others according to the usage properties,and six types as Bungalow,Low-rise building,Muti-story building,Mid-tall story building,High-rise building,and Super-high building according to the height,combining our research purpose with the principle of landscape classification.The conversion-in contribution rate,conversion-out contribution rate and retention ratio were used as the indexes of the transfer matrix method analysis to detect the change characteristics of architectural landscape types and their position and function.We divided the research area into 457 blocks of 0.3km×0.3km,and caculated the transformation area ratio of buildings in each block.Both the global spatial autocorrelation Moran′s I indicating overall clustering that exists in a dataset and the local spatial autocorrelation(LISA) cluster map dentifying 'interesting' locations and assessing the extent of spatial heterogeneity of the exploratory spatial data analysis were used to study the spacial distribution pattern of building transformation. The results showed that the main transformation of architecture landscape types was between the Not buildings and buildings(Residential building,Industrial building and Commercial building;Bungalow,Low-rise building and Multi-story building) from 1997 to 2008.There was significant difference existed in the transformation of building types and the spatial distribution in different time intervals.Residential buildings were the leading actor of architecture transformation from 1997 to 2002,while Industrial buildings were after 2002.The buildings were replaced firstly the Bungalow,secondly the Low-rise building,then the Muti-story building,and the newly increased buildings were firstly the Low-rise building,secondly the Mid-tall story building,then the High-rise building from 1997 to 2008.The Moran′s I of global spatial autocorrelation indicated that the building transformation was not distributing randomly but with prominent positive relation in space.The cluster map of local spatial autocorrelation presented concentrated building transformation in the local spatial scope.The position of the centralized transformation changed constantly over time.The implementation of urban renewal policies and transformation of regional function were the main factors for variation in architecture landscape pattern in the Tiexi District from 1997 to 2008.