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Ecological ecotone is one of the basic landscape ecological system research unit, is the important foundation. For the research of ecological ecotone studying global ecosystem can serve as an important index. Natural geographical environment is a complex and specific natural environment factor combination, this natural geographical environment factors in a certain extent, the combination of the corresponding decision of vegetation coverage, but due to the change of time, the whole natural systems also is met subsequently change, or because outside disturbance, and with a certain natural geographical factors change, make originally a regional vegetation growth changed, flora the area from start to appear overlaps, also appeared kind of ecological system to another type of ecological system phase transition area, space transformation environmental factors, such as organisms were in critical condition, and phase transition of ecological ecotone appeared. Ecological ecotone due to material flow or element migration, the crisscross vegetation composition will constantly changes, and for climate can influence the ecotone vegetation grows, so that in the ecotone can produce different vegetation composition, and the corresponding landform composition also is met subsequently on different, because in the ecotone seed breeding or human factors, and external disturbance, etc, are accompanied by other species of migration, new migration species not adapt to the change of environment, once and originally suit the environment of vegetation symbiosis, may produce genetic restructuring or mutations in the ecotone, then on will show more abundant species diversity. If the ecotone invading vegetation seeds on ability to reproduce is stronger, probably will invade the ecotone, and other border adjacent plaques of species fight for survival space, so will generate new species pattern. Depending on the species invasion to the ecotone seed reproductive capacity, if invasive plants ability to reproduce not strong word that the vegetation is not necessarily successful occupy living space and make the ecotone new species, but if invasive plants the seeds breeding ability, will be in the ecotone and itself is should the habitats of biological together, and may coexist, create new border to new species. So, ecological ecotone would be comparatively weak and very unstable very vulnerable to outside disturbance and produce change. Ecological ecotone are two ecosystem of connected area, this area is relatively complex, ecological environment is very weak, ecological ecotone have different scale, this study is based on small scales between vertical vegetation zonation ecotone namely vegetation ecosystem of interlaced zone. The changes to the ecotone on vegetation that succession law, not many previous studies, this paper to go dark coniferous forest - Betula ermanii changbai mountain is mainly lies in the vegetation, Betula ermanii and spruc ,fir as the research object, by traditional order.the survey sampling of vegetation,summarizes the ecotone vegetation as altitudinal gradients change and present change that to some extent in the future the ecotone instructions, namely Betula ermanii succession phase will gradually withdraw from the ecotone, and continuously, spruc, fir emplacement on the main species become the ecotone. The ecotone will gradually disappeared.
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