Used Point Patterns Analysis To Study On The Stability Of Plantation Structure For Hippophae Rhamnoides Linn.cv

The article choosed Hippophae rhamnoidesLinn.cv as the research object in wuxian country, which is the single advantage community, so the stability problem becomes plantations of primary problem. Using the method of space instead of time to choose different development stages Hippophae rhamnoidesLinn.cv at Dahekou forest farm in sunwu country, choose different habitats (scrap land, lowland, flatland, rolling hill)at the moment,through the results of the plantation of Hippophae rhamnoidesLinn.cv plot with high level and diameter level two aspects to analysis. With the method of point pattern analysis to analyse the plantation populations of the Hippophae rhamnoides Linn.variety from Russia and different age class individual distribution pattern and spatial associations, on the population structure and spatial pattern to describe population stability. Meanwhile researching at different stages and different habitats site quality of Hippophae rhamnoidesLinn.cv, find the differences with the stability of the relationship changes. The Hippophae rhamnoidesLinn.cv different stages population density differences reflect the performance in different periods and different competitive community. Different stages distribution pattern by the biological characteristics and environmental conditions, after the competition formed the existing distribution pattern.Though the age structure, younger level dividual has the most quantity in the three stages, the age structure present a growing trend, but the population in the proportion of younger level ndividuals in 11 years, the growth slow down. Obviously the population development experience. The population formed a new pattern after the self-regulation of population internal competition. The soil improvement showed consistency in different stages of Hippophae rhamnoidesLinn.cv, the soil quality of the site is the longer the better. There is manly a random distribution of the 2nd population, and there is not strong relationship in each age level, the population density is low, the overall is weak,the stability is poor, so the interference intensity is easy to cause the system collapse.There is the clumped distribution in the 8th population and each age level also show the clumped distribution, but the population exist competition between internal adjacent age level individuals, that's showed Population experienced stability to recession after the evolution gradually.The population density in 11th population is lower than that in 8th, that's explain there is the fierce competition between the age levels, many individuals was eliminated in the competition, there are more individuals in the young level(newborn individual) and high level maintain the stability of the population structure, but population growth has slowed.The population of Hippophae rhamnoidesLinn.cv in different habitats showed: lowland> faltland> scrap land> rolling hill.The average height and average diameter show different characteristics because of the difference in these habitats, the age structure are perrfoorming for normal distribution, the population is growth, the respective environmental in the different habitats then explaining sun water and soil nutrient conditions can affect the growth of Hippophae rhamnoidesLinn.cv plantation differentiation. The population pattern distribution in the different habitats is clumped distribution, which shows that the population has the commonness, as same as the consistency of the demand with the environment.The different habitats has the respective characterstics in the growth condition, and the differences showed in the respective age level distribution and the relationship between the age levels.The differences between growth environment influence the composition of each age level and their mutual relations, and finally result in different habitats in the spatial distribution of each population.Aiming at different stages and different habitat types Hippophae rhamnoidesLinn.cv plantation stability study and finally arrive that: the system stability is within a relationship between the population and the mutual relationship, spatial heterogeneity, environmental conditions difference, tiny terrain, and the influence of such factors, while the Hippophae rhamnoidesLinn.cv own biological characteristics is to determine the population distribution pattern as an important internal factors, finally affect the stability, in addition, human disturbance is also affected population stability as one of the important factors.