珠三角城市群城间生态缓冲区的空间分布与林分特征分析

Spatial Distribution and Stand Characteristics of Inter-city Ecological Buffer Zone in Pearl River Delta Urban Agglomeration

研究从珠三角城市群城间尺度出发,识别并筛选出城间生态缓冲区共54个,分析其空间分布及林分结构特征等指标。结果表明:(1)珠三角城市群内城间生态缓冲区数量较多,面积多在200~1000 hm^(2),但分布不均,主要集中在东莞—深圳—惠州以及中山—珠海—江门的城间交界处;(2)城间生态缓冲区的整体斑块形状不规则,且破碎化程度较高;(3)城间生态缓冲区的林分结构不够合理。纯林占比较高,树种组成单一;人工林占比偏高,达80.6%,但林分生产力低下,且单位面积蓄积量明显低于全国人工林水平;年龄结构不合理,同龄林和中幼龄林比重较大;生态公益林占比偏低,为50.79%,森林质量整体偏低。因此,未来珠三角城市群城间生态缓冲区的建设应注重空间分布的均衡性,斑块形状的规则性与连续性,以及林分结构的合理性。

Based on the intercity scale of the Pearl River Delta urban agglomeration,this study identified and screened 54 intercity ecological buffer zones,and analyzed their spatial distribution and stand structure characteristics.The results showed that:(1)the number of intercity ecological buffer zones cities in Pearl River Delta urban agglomerations is relatively high,most of which are 200 to 1000 hectares;however,they are unevenly spatially distributed,mainly located in Dongguan-Shenzhen-Huizhou and Zhongshan-Zhuhai-Jiangmen intercity adjacent districts;(2)Most of the intercity ecological buffer zones have irregular shapes and are highly fragile.(3)The stand structure of intercity ecological buffer zone is not reasonable.The proportion of pure forest is relatively high,and the composition of tree species is single,The proportion of plantation is high,up to 80.6%,but the stand productivity is low,and the volume per unit area is lower than the national level of the plantation.The structure of the age group is unreasonable,and the proportion of the same age and middle and young forests are large.Ecological public welfare forests accounted for a low proportion of 50.79%,showing an overall pattern of low forest quality.Therefore,the future construction of an intercity ecological buffer zone in the Pearl River Delta urban agglomeration should pay attention to the balance of spatial distribution,the regularity and continuity of forest patch shape,and the rationality of stand structure.