山地视觉景观的GIS评价--以广东南昆山国家森林公园为例

视觉景观评价是指某一特定区域具有视觉价值的景观的量化评价。山地是旅游开发的重要区域,山地景观是山地资源价值和山地生态环境的重要体现之一。以广东南昆山为例,将视野总面积、水域空阔度、景观层作为七仙湖环湖地区视觉景观评价的三大因子。以基础地理数据结合DEM作为数据基础,借助ArcGIS软件作为具体实现平台,设计景观层分析和视通性分析模型,对最佳坡度、最佳坡向、水文、交通条件叠加分析后过滤的62个样地进行视觉景观定量分析,确定评价标准,最后得到8号、23号、50号、55号样地较其他样地在整体视野,能见水域开阔和景观层次有明显优势。以此验证了将GIS空间分析技术应用于视觉景观评价的可行性,并为旅游观景点与度假村开发提供了科学依据。

The GIS-based visual landscape evaluation in mountain area: a case study of Mount Nan-kun National Forest Park, Guangdong Province

The visual landscape evaluation(VLE)is a quantitative evaluation of the landscape with visual values in a specific region. As an important area in tourism development, mountain landscape could reflect the major attributes of resource values and ecological environment in the mountain area. This paper takes the area around Qi-xian Lake as an example which is in Mount Nan-kun tourism area of Guangdong Province, and considers the total viewshed area, the water viewshed area and the landscape layer as three factors to evaluate visual landscape. It aims to quantize the approaches of landscape resource survey and evaluation. Module of landscape layer analysis and the viewshed analysis are designed on the basis of ArcGIS software as well as geographic data and DEM data. The area in the study is formed by setting out 500m buffer from the Qi-xian Lake surface, the VLE criteria is then established by using module of landscape layer analysis and the viewshed analysis to analyze visual landscape factors on the 62 sampling plots in terms of the overlaid conditions,such as the best slope,the best aspect,hydrological and transport. Through quantitative analysis and synthesis the evaluation factors of sampling plots, the results that the best sampling plots are No.8,No.23,No.50 and No.55,it means these sampling plots have 80% landscape factors at the fifth grade, they have obvious advantages in evidence in the broad field of vision and water viewshed area, as well as landscape layer. The worst sampling plots are No.4, No.40 and No.60, it means these sampling plots have 80% landscape factors at the first grade. Research process and the results indicate that VLE can use module which is scientifically designed by the principle of landscape layer analysis and viewshed analysis to obtain quantitative results. That is a trial for achieving standards and methods of aesthetic landscape evaluation. This paper verifies the feasibility of applying the GIS spatial analysis technology into VLE, putting forward the concept of evaluation index normalization. It changes the different classification standard of different factors into the concept of "grade", and the matrix of "1-5" grades for making comprehensive evaluation, especially replacing the complicated number comparison with graph analysis, which can help us get evaluation result fast when facing a great number of evaluation objects. Also we can get dynamic and accurate data support by assigning different weight to the visual landscape factors when we face the different landscape design or planning demands and provide a scientific basis for the tourist lookouts selection and tourism resorts development.