Study On Spontaneous Vegetation In Herb Layer And It’s Application In Hangzhou Xixi National Wetland Park

The plant landscape of urban parks is facing the demands of heterogenization,ecology and low energy consumption.From the perspective of new naturalism,the study of urban spontaneous vegetation(SV)and their landscape application will provide a new solution to the problem of urban landscape construction and ecological restoration.In this study,the spontaneous vegetation in herb layer in Hangzhou Xixi National Wetland Park were investigated by stratified random sampling.The spatiotemporal characteristics of species composition and community composition were statistically analyzed,and the influencing factors of community composition and diversity were explored.Based on the photos of SV in Xixi Wetland,the landscape preference survey was conducted from four levels: individual plant,community,scene and evaluation.Finally,based on the characteristics of SV in Xixi wetland,the landscape preference of the public and the management method of park greening,the landscape application of SV in urban park was discussed from three aspects of ecological community construction,landscape construction and scientific management.A total of 273 species of SV were recorded,belonging to 86 families and 221 genera.Poaceae and Asteraceae were the dominant families and 5 groups were the dominant species.Community diversity decreased from summer to autumn,and was highest and most stable in arbor land and shrub land.The community components tended to be woody in arbor land and constraction land,but herbaceous in grassland and farm land.In each habitat,the patch center tended to be herbaceous,and the revetment site tended to be woody and liana.The seasonal changes of community components in arbor land were the least,while those in farm land and shrub land were the largest.The whole year community was divided into 50 communities,among which 6 special groups were defined,indicating that some SV communities had wide spatial and temporal adaptability,while some communities had obvious selection of season,habitat type and patch location.The species richness of rock revetment and natural revetment was respectively affected by light and water level.Artificial vegetation significantly reduced SV diversity,in which the height of artificial vegetation was negatively correlated with the importance of herbaceous plants,positively correlated with the importance of tree seedlings,and negatively correlated with the importance of shrub seedlings.Residents had a positive attitude towards the establishment of SV landscape in urban parks.They were tolerant of the SV landscape in artificial vegetation and vertical revetment,and the expected coverage rate of natural land is more than 90%.However,the retention amount of SV should depend on the park style and scene effect,and the application location and landscape effect should be considered first by the public.It was considered that the best effect is to keep the SV in the mobile space and the ornamental and recreational facilities.The height of SV community should be about 30 cm.The wild interest of SV and the order of artificial landscape elements should complement each other.As for the community,a single species is not popular with the masses,while a complex and diverse but less chaotic and harmonious community was most acceptable to the masses.Both the specialist and non-specialist groups showed the same preference for community flowering,but the opposite preference for color contrast.In addition,people had diverse preferences for community colors and flowers,fruits,and leaves of individual SV.The application of SV in landscape not only has the requirements of landscape,but also has the requirements of ecology,which requires the combination of scientific and artistic construction approaches and reasonable management methods to achieve better results.In terms of ecology,we should fully grasp the general situation of SV resources in the region,respect the difference between habitats and seasonal change rules of SV communities,and build a stable community with high biodiversity and environmental adaptability.In terms of landscape,conservation objectives of SV communities should be formulated according to the style and site characteristics of the park,controlling the overall appropriate scene effect,shaping the appropriate appearance of the community,and carrying out appropriate details treatment.In terms of management,it is necessary to adopt hierarchical maintenance standards and multi-dimensional management mode in different zoning according to the spatial layout of the park green space,so as to achieve higher management effect with lower maintenance input.