Population Dynamics And Community Characteristics Of The Pinus Tabuliformis In The Liaoheyuan Nature Reserve

This study on the basis of the quadrat investigation and indoor analysis,to understand the existing state ofPinus tabuliformis and provide the basis for the protection and reasonable operation of P.tabuliformis forest in Liaohe NaturalReserve.population dynamics and community characteristics of P.tabuliformiswere discussed by using the basic theory and research method of plant geography,population ecology,quantitative ecology and community ecology.The results showed:(1)There were 67 species of vascular plants in p.tabuliformis community,which belong to 60 genera of 34 families,including 1 species of fern,and 1 family 1 genera and 1 species of gymnosperms,32 families 58 genera and 65 species of angiosperms,the community had distinctive features that some families contained many genera and 1 family only contained 1 genera and 1 species.Seed plants flora composition was simple,the temperate distribution occupied the largest proportion in all plants(40 genera,accounting for 67.8%of the total number of genera),other ingredient accounted for less.The plant distribution in the study area showed obvious characteristics of temperate zone.(2)The age structure of P.tabuliformis population showed an inverted J-type pattern and the number of seedlings was large.However,due to the high intensity selection through environmental sieve in the stage from seedling to sapling(from age class 1 to 2),the P.tabuliformis population would experience the first death peak.P.tabuliformis population presented a fluctuating trend of development and would experience three death peaks.the population dynamics of P.tabuliformis was characterized by decreasing in the early stage,being stable in the medium stage and depressing in the later stage.The survival curve of P.tabuliformis population was similar to the Deevy-? type,thus the population was classified as a stable one.(3)Stand age was an important factor affecting the spatial variation of the chemical properties of the soil in the forest.However,there was no evidence that suggest a linear relationship between forest age and the species diversity and richness index within the herb layer species.CCA ordination and Monte Carlo test results showed that the stand age,stand density,mean DBH,canopy density and slope were some significant influential factors determining the composition of the herb layer plant species.This indicated that in this region,the forest canopy structure dominated the herb layer distribution pattern of plant communities.(4)The VR value of the overall association of P.tabuliformis was greater than 1 and W>?20.05(15),and the population was significantly positive association.The correlation test showed that the number of species pair of positive association was more than species pair of positive association,and the community was in a stable state.