游憩型城镇景观林林内景观斑块类型特征研究

Characteristics of In-forest Landscape Patch Types of Recreational Landscape Forest in Urban and Suburban Area

以林内景观斑块结构为基础,对北京市各类公园游憩型景观林景观斑块特征进行了分析。北京市各类公园游憩型景观林可分为中密度锻炼型景观林、中密度休闲型景观林、中高密度锻炼型景观林、高密度休闲型景观林、低密度综合景观林等5类。而具有低林分密度、高草本覆盖、适量灌木覆盖、丰富的色彩数量、乔草或乔灌草结构的林内景观更符合大众审美。在16个景观斑块要素中,景观密度越大,色彩斑块的SHDI越低,草本覆盖率越高PLADJ和AI越高、而NP、PD、景观斑块形状指数LSI越低。景观指数变化对林内景观美景度影响程度依次为SPLIT>CONTAG>PAF>SIEI>SHDI。随着美景度等级降低,CONTAG呈现线性递减趋势,而PAF、SPLIT、SHDI和SIEI呈现非线性变化趋势。高密度和整齐划一式的林木排列以及简单的林下植被在一定程度上简化了林内景观要素的复杂性,并不利于提高林内景观质量,适当增加树种丰富度,通过提高垂直层次数量和多样化的林下植被,使用提高林下植被近自然程度、采取规则式和非规则式树木排列方式相结合的多样化水平空间配置,将有益于提高林下植被斑块色彩多样性,并可有效地提高林内景观质量。

Patch characteristics of in-forest landscape of the recreational landscape forests in different kinds of city parks in Beijing were analyzed based on the landscape color patch structures.The recreational landscape forests could be divided into five types,which included athletic landscape forest with medium stock density,leisure landscape forest with medium stock density,the exercise landscape forest with high stock density,leisure landscape forest with high stock density,integrated landscape forest with low stock density.And residents were more prefer to those landscape forests with the low stock density,high herb coverage,appropriate shrub coverage,rich in colors,the configuration of herbs and arbors or shrubs and herbs.In16 indicators of in-forest landscape patches,the higher the landscape density,the lower the SHDI of the color patch,and the higher the grass coverage,the higher the PLADJ and NP,and the lower the AI,PD and LSI.The rank of SBE values affected by landscape indicators were SPLITCONTAGPAFSIEISHDI.The CONTAG changed in linear way with the SBE reduction,and PAF,SPLIT,SHDI and SIEI changed in non-linear way with SBE reduction.High stock density and uniform distribution of trees wouldsimplify the complexity of landscape indicators of in-forest landscape,and were also unfavorable to improving the quality of in-forest landscape.And the quality of in-forest landscape would be validly improved by appropriate increase in species richness,increasing the degree of close to nature of undergrowth vegetation by means of diversifying the vertical stroma,combining regular and irregular tree arrangement to diversify spatial configuration of trees in horizontal direction.