| Forest parks are the core carrier of ecological construction.Scenic forest is the material basis of forest parks.However,most of the existing forest parks are developed on the basis of state-owned forest farms,and gradually become urban forest parks with the development of urbanization process in China.The main management purpose of state-owned forest farms is to provide timber,which greatly sacrifices the consideration of the visual aesthetic effect of landscape color of scenic forest.With the acceleration of urbanization,how to coordinate multiple functions and meet the growing public demand for leisure and entertainment has become an urgent problem for urban forest parks.As an important component of forest health,improving the quality of landscape color is of great significance to the recreation construction of forest health.In the past,the research of the construction of evaluation index system and spatial optimization method on landscape color mainly focused on experts,but less considered the consumption demand and experience preference of tourists,which is the main body of tourism.The objectivity and representativeness of the research are insufficient.As the new coronavirus is likely to be long-term,the isolation between people will become normal,the daily communication will be significantly reduced,and even many customs inherited for hundreds of years will disappear completely.In the future,the service industry will be greatly restrained,and people will reduce the demand for unnecessary services.For example,it will have a great impact on the tourism and other service industries,which may completely change the business logic of the tourism industry.Offline tourism has become online,landscape color visual recreation has become an important part of online tourism,and the advantages of visualization technology are highlighted.In the practice of color planning of scenic forest in China,however,no matter in the quantitative analysis of landscape color or color evaluation,there is no specific method guidance.It makes the quality of landscape color has no systematic evaluation criteria and indicators,and the evaluation is not universal and convincing.In this study,the data of forest resources investigation of Purple Mountain in 2017,World View-3 high resolution satellite image of Purple Mountain on October 29,2018(panchromatic resolution: 0.31 × 0.31 m,multispectral resolution: 1.24 × 1.24 m,short wave infrared resolution: 3.7 × 3.7m),DEM data(digital elevation model based on 1:10000topographic map of Purple Mountain,with spatial resolution of 3.3m × 3.3 m),Xiecheng travel tourist massive data and SPOI data of Xuanwu district scenic spots from Chengdu BIGEMAP corporation are taken as the data source,the quantitative analysis method of landscape color,the mining method of tourist preference of combination of direct participation and indirect participation,the extraction method of scenic forest parameters,the visual simulation method of landscape color,the interactive evaluation method of landscape color quality,the optimization management method of landscape color are studied.Through the research of this paper,an evaluation method of landscape color of scenic forest suitable for the north subtropical and warm temperate zone in China is explored,and a set of optimized management scheme of landscape color of scenic forest is summarized,which provides scientific reference for the color planning of scenic forest and the construction of recreation,so as to promote the sustainable development of forest tourism and recreation industry.The main conclusions of this study are as follows:(1)In the quantitative analysis of landscape color,the autumn with the richest color spatial composition and the highest spatial pattern index is taken as the case study season for the follow-up study.The color of the study area in autumn is extracted and quantified,and the main color hue values,the saturation value of main landscape color,the brightness value of main landscape colors,the proportion of main colors in each sub-compartment landscape,the number of red blocks,the number of red-orange blocks,the number of orange blocks,the number of orange yellow blocks,the number of yellow blocks,the number of yellower yellow green blocks,the number of yellow green blocks,11 color factor parameters are obtained.After quantitative analysis,the range of the three attribute values of the main landscape color in the whole study area in autumn 2017 is determined.The overall autumn landscape color is mainly composed of yellow(the largest proportion),yellower yellow green and orange yellow.The color composition of autumn landscape and the spatial distribution pattern of hue,saturation and brightness are defined.Through correlation analysis,the five factors,the number of orange blocks,the number of orange-yellow blocks,the number of yellow blocks,the number of yellow-green blocks and the proportion of main colors in each sub-compartment landscape,are all significantly correlated with the three attribute values of main landscape color.(2)Based on the study of tourists’ indirect and direct participation method,tourists preference is determined: viewing preference is flat and up viewing angle,which can obtain the medium and short viewing distance of landscape texture details to a certain extent.And tourists always prefer the single color with low hue value and more color types in each scene.Combined with tourism big data tourist keywords,through SD(Semantic Differential)method,nine main semantic orientations are obtained: five semantic orientations belong to the category of color quality evaluation,two semantic orientations belong to the category of color visual sensitivity evaluation,and two semantic orientations belong to the category of color visual absorptivity evaluation.Based on the study above,the evaluation index comprehensive system of color quality is constructed,includes the color quality evaluation,including the color vividness,color markedness,color integrity,color diversity and color aesthetic 5 evaluation index factors;the color visual sensitivity evaluation mainly focuses on four evaluation indexes: visual probability,relative visual distance,contrast between landscape and environment,and public attention;the color visual absorption is evaluated by slope,aspect,terrain diversity and vegetation richness.(3)Through the three-dimensional visual simulation method,the three-dimensional visual scene construction of scenic forest landscape color in the study area is constructed,which can be used for online interactive color quality evaluation.In the evaluation of each index of landscape color quality,the weight of five evaluation indexes is determined(the weight of color integrity is the largest),and the evaluation model of landscape color quality is obtained.The distribution trend of color quality in the whole study area is dominated by intermediate quality,high-quality landscapes are concentrated in the west and south,and low-quality landscapes are concentrated in the east;the weight of four evaluation indexes is determined,among which the weight of public attention is the largest,and the evaluation model of color visual sensitivity is obtained.The distribution trend of color visual sensitivity in the whole study area is mainly characterized by intermediate color visual sensitivity landscape covering the whole study area;the four evaluation indexes of color visual absorptivity are evaluated,and the weight of slope aspect is the largest.The evaluation model of color visual absorptivity is obtained.The color visual absorptivity grade of Zijin Mountain is "low in the east,middle in the west,high in the north and south".The comprehensive evaluation of landscape color quality of scenic forest in the study area is based on the evaluation scores of color quality,color visual sensitivity and color visual absorptivity,which are given their respective weights(the weight of color visual sensitivity evaluation is the largest),and the comprehensive evaluation model of landscape color quality is established.The overall landscape color comprehensive quality grade shows the distribution pattern of "high in the southwest,low in the east,and medium in the rest" : the western(and northern areas)and southern areas of the study area are mainly composed of high comprehensive quality landscape color,the eastern area is low in color comprehensive quality,and the landscapes with medium comprehensive quality are all over the other areas of Zijin Mountain.The comprehensive evaluation of the landscape color quality of the six scenic spots and different altitude areas of Zijin Mountain is carried out,and the score size and grade distribution of each scenic spot and each altitude area are obtained,and the landscape color characteristics of each area are described.Among them,the color landscapes with high color quality,high color visual sensitivity,high color visual absorptivity and high color comprehensive quality are the most in White Horse Park,Ming Xiaoling Mausoleum and Sun Yat-sen Mausoleum scenic spots respectively,and the average value of landscape color comprehensive quality in Ming Xiaoling Mausoleum scenic spot is the largest;The color landscapes with high color quality,high color visual sensitivity,high color visual absorptivity and high color comprehensive quality are the most in low altitude area,high altitude area,high altitude area and high altitude area,respectively,while the average value of landscape color comprehensive quality in high altitude area is the largest.In the analysis,the color landscape of different landscape color comprehensive quality grades in Purple Mountain forest park can be described as follows:High quality color landscape is mainly located in White Horse scenic area in the west and Ming Xiaoling Mausoleum scenic area in the south of the study area.A variety of seasonal typical color deciduous broad-leaved tree species are the main dominant tree species,and together with other soft and hard broad-leaved or coniferous tree species constitute a mixed forest color landscape with complex structure.The color landscape is rich and bright.It can present red,red orange,orange,orange yellow,yellow,yellower yellow green color patches.The landscape is mostly formed in the north gentle slope area.The color landscape is covered by rich road network and has high accessibility.The viewer has enough viewing space and the viewing quality of color landscape is high.The medium quality color landscape is distributed in the six scenic spots,and forms the base of the whole landscape forest color landscape.The color landscape of broad-leaved or coniferous broad-leaved mixed forest is mainly composed of at least one typical color leaf tree species.Landscape color is rich,but there are only about two kinds of color patches,which are generally formed in the east-west slope of the gentle slope area,and the landscape level is general.Most of the landscapes can be easily viewed by the viewers themselves,but some of the landscapes are limited,or the landscape is not easy to be perceived by the viewers,and the overall color landscape quality is general,which has a certain space for improvement.The low-quality color landscape is mainly located in the eastern natural landscape of Purple Mountain forest park.The mixed forest color landscape is mainly composed of evergreen hardwood and coniferous trees.The color landscape with colored leaves is also the dominant species,but the seasonal color change is not obvious.The overall color of color landscape is single,most of which are green color,supplemented by yellower yellow-green,yellow green,greener yellow green color patches.Most of the stands grow in the south slope with a certain slope,and the landscape is disordered.There are few accessible roads near the color landscape,and part of the landscape is located in the blind area of the viewer’s sight,the overall color quality of the landscape is poor,it needs reasonable management to improve the comprehensive quality of the landscape color.(4)Based on the theory of forest landscape ecology and forest aesthetics,the paper takes the basic characteristics of urban national forest parks and the overall planning of Purple Mountain Forest Park(2014-2023)as the main optimization basis,and takes the color landscape of Purple Mountain scenic forest to coordinate the contradiction among the demands of scenic tourism,ecological protection and citizen leisure.The optimal management system of the overall optimization principle is to give full play to the various functions of Forest Park.Based on the ecological sensitivity analysis,comprehensive evaluation of landscape color quality and the existing management technical regulations of scenic forest,21 sub-compartments can be optimized.According to the different characteristics of the sub-compartments,the paper puts forward the optimization management method which is mainly based on the evaluation results of color quality,color visual sensitivity,color visual absorption and semantic analysis of the key words(including tourist attractions)of the tourists evaluation on big data platform.In the analysis of 21 targeted color scenic subcompartments,the improvement of color quality is mainly based on the advantage color substitution in subcompartments method(including the advantage color substitution in subcompartments method and the advantage color substitution outside subcompartments method),takes the color-leaf advantage tree species as the optimization essence;the color visual sensitivity enhancement is mainly based on the viewing spot network method,takes the road system and the site layout as the optimization essence.If there are scenic spots in the subcompartments,the sensitivity of scenic forest can be improved by improving the cost performance of scenic spots;the improvement of color visual absorption is mainly based on the regional micro topography method,with regional landform as the optimization essence.If there are scenic spots in subcompartments,the attraction of scenic forest can be improved by enhancing the interest of scenic spots or increasing the biological landscape. |
