Dynamic simulation of forest landscape succession based on LANDIS model in Tianbaoyan, Fujian Province of southern China

ObjectiveThis study aims to understand the developing trend of forest succession in Tianbaoyan National Nature Reserve, Fujian Province of southern China and provide a scientific basis for the development of management policies to protect the rare plants and biodiversity.

MethodUsing the spatially explicit landscape simulation model LANDIS Pro 7.0, this paper analyzed the forest landscape evolution of Fujian Tianbaoyan National Nature Reserve by stimulating the dynamics of vegetation's ecological succession in the next 300 years (2016-2316). The landscape statistical analysis software Fragstats 3.3 was used to calculate the area percentage of dominate tree species, the landscape aggregation, the fractal dimensions, the diversity and evenness indices. And the variation tendency of all species' age-classes during simulation time was analyzed.

ResultDuring the succession period, the patch dimensions of all tree species except for Phyllostachys hetericycla ranged in 1.00-1.06, indicating that the shape of the landscape patch was relatively regular and not much changed. The Shannon-Weiner diversity index SHDI showed a trend of increasing first and then decreasing, the Shannon-Weiner eveness index showed a trend of falling first and then rising.Moreover, their speed of change gradually slowed, indicating that the change of tree species gradually stabilized. The degree of aggregation of broadleaved forests remained stable for 150 years after the increase in the first 150 years, and its area kept growing until the end of succession, with mature forests and young forests as the main factors; the aggregation of Rhododendron simiarum and Tsuga longibracteata increased during the entire succession period, and their area also increased during the middle and later periods of succession, and the increase was mainly in young forests.The area of Cunninghamia lanceolata increased in the first 150 years, and the proportion of young forests also gradually increased during this period; the area after the first 150 years remained stable until the end of succession, mainly in middle-age forests and near-mature forests; the degree of aggregation remained stable but increased slightly; the degree of aggregation of Cryptomeria fortunei kept stable during the first 100 years of succession and decreased during the later 200 years. At the later stage of succession, the entire forest was dominated by over-matured forests, followed by middle-age forests; the forest of Pinus massoniana was dominated by over-matured forests throughout the entire succession period. The proportion of young and middle-aged forests was very low. Also, over-matured forest occupied a major position and mature forests followed in the Phyllostachys hetericycla forest. Moreover, the degree of aggregation of Casuarina equisetifolia and Phyllostachys hetericycla was decreasing during the succession period.

ConclusionThe results show that the populations of broadleaved tree species will increasing and moving to the direction of complex zonal evergreen broadleaved forest system; the forest of Casuarina equisetifolia, Cryptomeria fortunei and Phyllostachys hetericycla will gradually be replaced in the community over time; the forest of Cunninghamia lanceolata, Tsuga longibracteata and Rhododendron simiarum shows a good developing trend during the succession period.