Simulation Of Forest Landscape Dynamic Change Based On Landis-â…¡ In Huanglongshan, Shanxi

LANDIS-II is a spatially explicit landscape model with pixel-based and developed byUniversity of Wisconsin at Madison. The model is used to simulatedynamic change of landscape at large space and long term scales under natural disturbanceand human disturbance. Huanglongshan forests plays an important role on ecological area inthe southeast of loess plateau in northern shaanxi and the country, so that was very useful tosimulate the dynamic change of landscape at large space and long term scales to understandthe forest succession rule and track the driving force caused by the changes of forestresources, thus we can have a better management of forest resource.In this paper, a spatially explicit landscape model LANDIS-II was applied to simulatethe dynamic natural succession of forests without considering the disturbance such as wind,fire, harvest, diseases and insect pests in Huanglongshan, Shanxi within300years (2004-2304a), This paper based on the theory of forest succession and landscape ecology. Thelandscape statistical software package APACK was used to calculate the landscape patternindex such as area percentage of dominant tree species, the aggregation index reflecting thespatial patterns of species, the fractal dimension index, shannon’s diversity and shannons’sevenness index of landscape. Variation tendency of all species’ age-classes during simulationtime were analyzed. On this basis, the dynamic changes of Huanglongshan forests landscapepattern was discussed and researched.The results indicated:(1) About patches percentage, Pinus tabulaeformis and Quercusliaotungensis presented a tendency which increased after slightly decreased, and always kepta larger proportion of patches percentage. Populus davidiana and Betula platyphylla’s patchespercentage was decreased after50years and slightly increased when the succession lastedlater period and. Platycladus orientalis’s patches percentage was remained stable during thesuccession process, and slightly increased when the succession lasted later period.(2) Aboutaggregation index, Pinus tabulaeformis kept a declined tendency during the whole successionprocess. Quercus liaotungensis had a slightly change before170years, and presented a fluctuant decreased tendency when the succession lasted later period. Populus davidiana andBetula platyphylla’s aggregation index kept a higher level during the whole successionprocess, and their aggregation index were more stable than Pinus tabulaeformis and Quercusliaotungensis’s. Platycladus orientalis’s aggregation index was remained stable and kept ahigher level during the300years’ succession process.(3) About the fractal dimension index,Pinus tabulaeformis and Quercus liaotungensis presented a increased tendency, Populusdavidiana and Betula platyphylla presented a fluctuant change, showed dropped after the firstrise and then rise. Platycladus orientalis’s fractal dimension index was remained stable duringthe succession process, and slightly increased when the succession lasted later period.(4)About shannon’s diversity and shannons’s evenness index of landscape, the shannon’sdiversity of study area presented a increased tendency during the whole succession process.The shannons’s evenness index presented a tendency that decreased after increased, it was anegative correlation between the shannon’s diversity and shannons’s evenness index when thesuccession lasted later period.For the analysis of the results the following conclusions can be drawn: that Pinustabulaeformis was the dominant species of coniferous trees and Quercus liaotungensis wasthe dominant species of deciduous trees. Pinus tabulaeformis and Quercus liaotungensispresented a alternate growth fastigium during the next300years, it indicated that the climaxcommunity of Huanglongshan forests is oak pine forests which Competing andinterdependent with each other. The fractal dimension index of forests presented a increasedtendency, it indicated the distribution of forests on study area changed from larger areaforests with high connectivity to small block forests with low connectivity, that mean thefragmentation of forests became increased.