Study On Landscape Construction Of Vertical Green Wall In The Pearl River Delta

The construction of vertical green wall expands the urban green space,helps to create a more livable living environment,and promotes the construction of ecological civilization.However,there are some problems in the landscape construction of vertical greening wall,such as the high cost of management and maintenance and poor sustainability of landscape effect,which seriously restrict the sustainable development of urban vertical greening.Through the research conducted in the present situation both at home and abroad,the vertical greening wall construction needs a clear guiding ideology and technological means.The future of urban vertical greening landscape construction wall provide beneficial theoretical basis and technical reference combining the two typical cases,vertical greening walls in Guangzhou and Shenzhen,with vertical greening landscape construction wall technology,evaluation and optimization strategy of maintenance and management,landscape studies.The main research conclusions are as follows:(1)In the application of vertical green wall plants,there are 38 kinds of plants in the10 sample points,among which there are 13 kinds of woody plants,21 kinds of herbaceous plants and 2 kinds of lianas.All kinds of plants are suitable for vertical green planting.The most common plant family mainly has the South astraceae,the Lily family,the Pentacaceae,the kidney fern family,the gramineae and so on main application plant.Among them,plants with the highest frequency of application are Schefflera octophylla,Schefflera Actinopylla,Epipremnum aureum,Arrhenatherum Elatius,Nephrolepis auriculata,etc.These plants have the advantages of evergreen,low maintenance and long-lasting landscape.They are attractive because of their ornamental flowers and leaves,which is helpful to improve the landscape effect of vertical greening.(2)Through field investigation,it is found that the vertical plant walls in Guangzhou and Shenzhen can be divided into three types: wire mesh frame,steel frame and direct fixed frame.Plant wall planting technology can be divided into three types,namely module type,cloth bag type and planting trough type.Among them,there were 7 cases of modular plant wall,accounting for 58.3%.There were 4 cases of cloth bag type plant wall,accounting for 33.3%.There was 1 case of planting trough wall,accounting for 8.3%.Irrigation methods are mainly artificial irrigation and automatic irrigation.The water retention properties of matrix,choose peat soil,coconut chaff,fertilizer,loose scale perlite,sediment,water moss,planting soil are test material,and the results show that the optimal,loess and water retention of sponge was 77.20%;the worst moss peat soil and water of water retention,at 41.80%;the peat soil has good drainage performance,whose quality is light: 0.684 kg.Combined with the bearing capacity of the wall and the gravity and water retention of the matrix,mixed matrix peat,pine scale,perlite and silt are recommended as vertical green wall plant cultivation.(3)To research the vertical greening of wall to carry on the comprehensive evaluation,the percentage difference method is adopted to divide the community landscape level through the establishment of AHP hierarchy model.The comprehensive evaluation index as level Ⅰis more than 80%,the level Ⅱ 70% ～ 80%,and the level Ⅲ is less than 70%.The results show that the levelⅠof vertical greening wall are mainly distributed at Futian and Nanshan district in Shenzhen.The number of it is 3,accounting for 20% of the total.The levelⅡis distributed in all districts with 4 vertical greening walls,accounting for 40%of the total.The level Ⅲ of vertical greening walls are 5,accounting for 40% of the total.The level I of vertical greening wall to build plants in abundance,coverage,density,layer thickness and community health degree has a competitive advantage.Plants are preferred in wall of vertical greening plants using tone and the level Ⅱ of vertical greening wall in vertical greening ecological value,aesthetics,maintenance management has a certain advantage,which is also in the pearl river delta using the vertical greening patterns and plant species.The level Ⅲ is mainly affected by index of aesthetics,the maintenance management of the overall score is low,and part of the vertical greening walls exists serious imbalance.(4)Landscape construction strategy of vertical green wall.In order to select the frame structure of the green wall,plants,cultivation substrates and drip irrigation system,the research and exploration on vertical greening of low-maintenance and long-lasting landscape were carried out to optimize the method of plant allocation.The greening wall frame using wire mesh frame and steel bar structure frame is recommended.According to the experiment,the mixed matrix of 5 peat,pine scale,perlite and silt has good water-retaining property and light weight,so it is suitable to be used as plant cultivation base.The irrigation system uses automatic irrigation which is time-consuming and can reduce manual labor.The plant variety of the green wall shall be composed of at least 3kinds of plants,and the number and variety of plants shall be as rich as possible according to the environment or theme of the green wall.At the same time,the look of a plant is one of the key factor,according to the summary of the different types of plants selected,such as Schefflera octophylla,Arrhenatherum elatius,Asparagus cochinchinensis,Loropetalum chinense.