Study On Bryophyte Vegetation Restoration Of A Degraded Peatland In Changbai Mountains Based On The Regulation Of Water Table Level,Propagule Transplantation Modes

Many peatlands around the world have suffered from drainage,resulting in changes in soil structure,plant community composition and carbon accumulation.The technology on restoration and reconstruction of peatland is one of the study hotpots in wetlands restoration ecology,and vegetation restoration is the core for peatland restoration.Sphagnum are the most important plants charcoal plant in North peatland.Propagule transplantation of Sphagnum is one of the important factors affecting restoration of peatland vegetation,but the effect of transplantation modes on restoration success has been lack of comparative research.In this study,the degraded Baijianghe peatland in Changbai Mountain area was selected as the research site,and S.flexuosum,S.magellanicum,and S.fuscum collected from natural habitats were chosen as experimental materails.Through field transplantation experiments,the water table level is raised.Firstly,based on the niche principle,the relationship between the stratified transplantation method of Sphagnum propagules and the Sphagnum coverage and height in different establishment periods.Secondly,based on the theory of bryophytes,combined with the water level gradient,the effects of the density effects of different species of Sphagnum on the restoration of Sphagnum vegetation were explored.In order to determine more reasonable and efficient peatland vegetation restoration technology,improve the theory of peatland restoration,and contribute to the restoration of ecological development.The main results and conclusions of the study are as follows:(1)water table level significantly affected the establishment of S.flexuosum,S.magellanicum and S.fuscum,their cover increased obviously with water table level increase The increase in water table level has significantly promoted the growth of Sphagnum,mainly in the aspect of Sphagnum coverage and high growth.Under low water conditions,the growth of S.flexuosum,S.magellanicum and S.fuscum was inhibited,the coverage and height growth were the lowest,and the whole growth season lasted.Indicating that low water table level is the key factor limiting the establishment of Sphagnum and determined the basis and possibility of the growth of Sphagnum.(2)In the stratified transplantation experiment of Sphagnum,the three transplantation methods showed different performances at different stages of the experiment.At the beginning of the experiment,the S.flexuosum was located in the lower layer,and the S.magellanicum was located in the upper layer,which significantly promoted the growth of Sphagnum,but had little effect on the total coverage of Sphagnum.However,in the late stage of planting,the Sphagnum transplant method significantly affected the coverage of Sphagnum and improved the success rate of Sphagnum establishmen.(3)In the density transplantation experiment,among the three transplant densities of 5:1,10:1,and 15:1,5:1 and 10:1 predominate,due to the Regulation of self-thinning,the two transplant densities are not Significant differences.There may be a devaluation between 5:1 and 10:1 that needs further exploration.In addition,considering the economic principle of wetland restoration,it is recommended that the reintroduction of 15:1 transplant density in Baijianghe peatland is the best.(4)For the Sphagnum species,the Sphagnum establishment capacity is in the order of large to small,followed by the S.flexuosum,S.magellanicum and S.fuscum.Among them,S.fuscum is not recommended for reintroduction in the initial stage of restoration.If the vegetation diversity is not considered,the S.flexuosum has the best recovery effect in the degraded peatland.(5)Water table level and Sphagnum transplant density,there is a significant interaction.The expression of Sphagnum density effect is different under different water table level conditions.Under high water conditions,the introduction of sphagnum propagules was carried out in a high-density 5:1 manner,and the Sphagnum coverage was the best.When the water level decreases,the high density advantage gradually decreases,the water level decreases to a certain extent,the sphagnum density advantage is lost,the intraspecific competition is fierce,and the self-thining effect occurs,and the sphagnum growth is limited.Therefore,in the degraded peatland with better water level conditions and the transplant density can be appropriately increased,for example,by 5:1,and the water level condition is relatively suitable to be reintroduced at 10:1 or 15:1.(6)The improvement of water level promoted the establishment of sphagnum and shortened the recovery time.Under the control of high water level,the sphagnum reached the same coverage condition for about 4 months ahead of time than low water table level,and speeded up the pace of the recovery of drainaged Peatland.