次生林为主的自然风景林林内景观质量评价

以次生林为主的自然风景林林内景观质量多处于中低状态,而调整改造的主要依据是林内景观质量的评价结果。笔者以吉林市大石门沟森林公园次生风景林为例,以美景度为目的指标,采用SBE法,应用相关分析、方差分析、逐步回归、聚类分析等方法,确定了次生风景林林内景观质量的主要影响因子,建立了质量评价预测模型,并对研究对象进行了景观质量类型划分。结果表明:树木姿态(X4)、自然程度(X17)、透视距离(X16)和灌木高度(X8)是影响次生风景林林内景观质量的主导指标,并建立美景度模型:MSBE=-128.391+15.63X4-3.615X8+20.379X16+17.933X17; 美景度随树木姿态、自然程度和透视距离等指标得分值的提高而显著提高(P<0.05),随灌木高度的提高而显著降低(P<0.05)。根据聚类分析结果,将林内景观分为高、中、低美景度景观3种类型。针对研究对象的3种质量类型提出了调整结构、增强自然性、优化林相、适当控制灌木密度与高度等具体林分改造建议。
The landscape quality of natural scenic forest mainly made of secondary forest was in a state of medium or low. The main basis of adjustment and transformation was the result of quality evaluation of in-forest landscape. A secondary scenic forest at Corn-growing Ditch Forest Park's in Jilin City, Jilin Province was taken as an example in this study. The beauty degree was objective target and the Scenic Beauty Estimation(SBE)method was adopted in this study. Main factors affecting the landscape quality of the forest were determined through correlation analysis, ANOVA analysis, regression analysis and cluster analysis. At the same time, a prediction model of quality evaluation was established, and the types of landscape quality were devided. The results showed that the tree form(X4), naturalness degree(X17), perspective distance(X16)and the shrub height(X8)were the main indicators that influenced on the landscape quality of secondary forest. The beauty degree model was built: MSBE=-128.391+15.63X4-3.615X8+20.379X16+17.933X17. With the improvement of tree form, naturalness degree and perspective distance's scores, the beauty degree improved significantly(P<0.05), and when the height of the shrub got higher, the beauty degree's level reduced significantly(P<0.05). According to the results of cluster analysis, the forest landscape was divided into high, medium and low beauty degree of landscape. On the basis of three quality types of the study objects, the forest stand transformation approach were suggested, such as structure adjust, naturalness degree enhancement, forest form optimization, proper shrub's density and height control