Too Baishan Hua Lin Spatial Pattern And Model

It seems incompatible to the stability of Betula spp. forest in Mt. Taibai: the study of palynology and visible dominant distribution proved the stability; but field investigated data implied the instability. This paper intends to understand the stability and mechanism of Betula forest in Mt. Taibai, by population structure and spatial pattern of it. Additionally, a Multi-Agent based hybrid model was built to simulate the population dynamics of competitive species of the forest.An across-scale analysis was conducted to characterize the population and spatial characteristics of an old growth Betula forest located in Mt. Taibai, PR China. The study was designed to analyse the population structure for assessing different tree species spatial distribution patterns of different trees' classes to increase understanding of the effects of population dynamics, spatial structure, associations, co-existence, recruitment and forest form on pattern-process relationships in the forest. Linking from life tables and stems distribution of different species, the modified spatial point analysis methods, univariate and bivariate NDF (Neighborhood Density Function) which closely related to Ripley's K statistic but without cumulate effect were employed to capture spatial distribution pattern and characteristics of the forest.The results of this study shows: There was a high mortality in the Betula populations at the state of seedlings and saplings. The Abies, which was thought will replace the Betula, was not an increasing population in the forest, and couldn't be the edificato of new community. All snags in the forest were mostly composed by uprooting and snapping, and probably created microsites (forest gap) which forest recruitment relied on. Whether standing trees or snags of all species were assembly distributed within each age class at most spatial scales with all altitudes but randomly distributed when all classes were analyzed. After joint population structure and spatial pattern were conducted, this related changes in population dynamics to changes in spatial pattern. These linked studies provide a measure of ecological significance relative to statistical significance between population structure and spatial patterns. Betula stems were significantly negatively associated to the Abies stems at most scales, indicated intense competition between them. Recruitment of Betula above a given scale were only positively associated with conspecific snags, suggesting that seed dispersal and vegetative regeneration influenced the spatial patterning of Betula by itself. Abies influenced recruitment, showed weak relatively pattern with snags of all species, indicate that it could establish without gap makers limition but with low efficiency. The results elicited from NDF suggested that different regeneration strategies among the species play an important role in regulating their spatial distribution patterns, while competition between individuals of Betula and Abies at the all stage also contributes to spatial patterning of these communities. The recruitment limitations of Betula and Abies may affect the persistence of these species and the long-term dynamics of the forest. The mechanism of co-existence of different species in Mt. Taibai should be investigate and discuss in a further research.Simulating by the model, which linking from the meta-population dynamics model and fugitive coexistence hypothesis, and based on Multi-Agent technology, indicated a sustaining result of co-existence of two species in Mt. Taibai. Under current condition of disturbance and structure, Betula could be the dominant species in the forest for a long time.As sun-loving species, Betula requires disturbed microsites (e.g., uprooting and snapping) and canopy openings for regeneration in the forest, in which the patterns appeared to persist in the distribution of standing trees and were consistent with highly aggregated patterns of snags caused by natural disturbances across the stand. It suggested that the cohort of B. albo-sinensis population in Mt. Taibai is clumped distribution in space and, this intraspecific aggregation of different cohorts which is a kind of pulsed recruitment might be capable of keeping population stability.