Research On The Optimization And Application Of Resource-Efficient Landscape Plants

The process of urbanization in China has accelerated the pace of landscapeconstruction. But unreasonable landscape construction caused a serious waste ofresource.Therefore more and more attention was paid on the concept ofresource-efficient landscape.But current research about resource-efficient landscapemainly focused on theoretical analysis and interpretation of policy.The qualitativeanalysis is more and the quantitative analysis is less. The optimization model of theresource-efficient landscape is built after making extensive analysis which based ona great deal of basic data through field surveys and analysis of the ArcGIS. Theresearch methods and works were mainly as follows:(1)Based on fuzzy comprehensive evaluation of fuzzy mathematics theory, thetechniques of hybrid programming between C++language and T-SQL was used tobuild an optimization system for plants application of resource-efficient landscape.The stored procedure was used to encapsulate the fuzzy comprehensive evaluationfunction. Fuzzy comprehensive evaluations for323species of landscape plantshad been made respectively based on the12green spaces from Jining or Nanjing.Thus the economy indexes, ecological adaptation indexes and comprehensiveselection indexes of each plant had been calculated in two places.(2)After using nondestructive measurement method to determine the number ofplant leaves and using AutoCAD to calculate leaf area, the flat leaf area index andthree-dimensional leaf area index of226species of landscape plants had beenmeasured and calculated. The area of the greening land, the plant cooling influencerange and the plant coverage were measured and calculated through ArcGIS. Onthese bases the vegetation quantity database was established. The green indexes andvegetation quantity index of the12green spaces were calculated by using SQL.(3)Based on correlation analysis by using these data through SAS9.1.3, it hadbeen found out the impact factor which had strong correlation with the landscapeplants' weighted average value of decreasing temperature, the economy indexes andvegetation quantity index.It has been determined7single variable linear regressionequations about weighted average value of decreasing temperature between otherfactors,19single variable linear regression equations about economy indexes,25single variable linear regression equations about vegetation quantity index and1multiple linear regression equation about economy index.(4)Through analyzing the goodness of fit of the regression equation and gettingrid of the regression equation with strong correlation,the critical factor was found which restricted economy index and ecological benefits. Then the optimizationmodel of the plants of resource-efficient landscape was established on this basis.Optimization calculation about the plants of12green spaces were done through thisoptimization model.The conclusions were as follows:(1) The same plant's economy index, ecological adaptability index and suitableselection index were different between different places. The plant's economy indexwould rise, the ecological adaptability index and the suitable selection index woulddrop, and the plant species to choose would be inadequate with the rising oflatitude,the decreasing of the precipitation and the decreasing of the averagetemperature in January. Otherwise with the decreasing of latitude, the increasing ofthe precipitation and the average temperature in January, the index would show theopposite change, and the plant species to choose would be abundant. From averageanalysis, the economy index of landscape trees was the highest, but thenon-wintering herbaceous flowers' was the lowest. The wintering herbaceousflowers and lawn plants were between them and their D-value with landscape treeswas little.(2)In order to facilitate the study of vegetation quantity, vegetation quantityindex was divided into two-dimensional index and three-dimensional index.Three-dimensional leaf area index was constructed. The usually sense of leaf areaindex was defined as the plane leaf area index. The impact of the same species withdifferent planting ways on leaf area index was not significant, but the averagesshowed the following trend: group planting shrubs＞scattered planting shrubs,scattered planting shrubs＞arbores, group planting shrubs＞arbores.In the case of the same land area, the tridimensional vegetation quantity wouldgenerally increase when the shrubs planted from scattered planting way to groupplanting way.(3)From counting12green spaces' afforestation index and vegetation quantityindex, it was found: the new-built green spaces had high hardened ground rate. Plantconfiguration was not reasonable. The ratio of tall arbores was low. The phenomenonof big arbores transplanting was common. The greening land's LAI was low, therebyit affected the whole green space's ecological benefits. From12green spaces'economical assessment values calculated by level parameter evaluation method, itwas found that the new-built green space's economical assessment values was low,but those built long time ago often had high vegetation quantity index andeconomical assessment value. They had high ecological benefits. Their plantsconfiguration was reasonable, ornamental and recreational function was strong.(4) The temperature of the green land and the height of the plants showed negative linear correlation. The cooling effect of the landscape plants and hardenedground rate was negatively correlated, but it was positively correlated with greeningland rate. It could effectively reduce the temperature value in microclimateenvironment if the hardened ground weas grown plants. However, the improvementof the air humidity was not obvious.(5) Landscape indices revealed only the geometric properties of the plantdisposition,and the correlation between vegetation quantity index or economy indexwas not significant. Therefore, landscape indices could facilitate analyzing spaceconfiguration properties of the landscape plants. But the ability to explain theeconomy index and vegetation quantity index was not strong. This also Illustratedthe limitations of landscape indices on resource-efficient landscape study.(6) Through correlation and regression analysis between the indices, it wasfound that the impact of arbores, tall arbores and lawn plants on the leaf area indexwas large. The tall arbores were slightly larger than the arbores. Impact of tallarbores, herbaceous flowers, flowering plants on economy index was larger, tallarbores' impact was slightly larger than the arbores, the influence of herbaceousflowers were slightly larger than flowering plants. Tall arbores and flower plant'sinfluence were larger under comprehensive consideration. Increasing of theproportion of the tall arbores would increase greening land leaf area index andthe economy index of green lands. Increasing the proportion of floweringplants would enhance the ornamental value of the green space, but would reducethe economy index. Defining the suitable proportion of tall arbores and floweringplants was significant for resource-efficient landscape.(7) A multi-objective optimization model was established based on the multipleregression equation of economy index and single variable regression equation whichwas derived from projected area ratio of tall arbores and the LAI of greening areas.12green spaces were divided into various levels in accordance with thecorresponding properties through cluster analysis. By defining the optimumdisposition proportion of landscape plants and inputting them into the optimizationmodel, the optimization calculation was done by usingMATLAB7.8.0and the optimal projection area of the tall arbores and floweringplants was determined.