Mangrove forests in a peri-urban setting: the case of Mombasa (Kenya)
Mangrove forests in a peri-urban setting: the case of Mombasa (Kenya)
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城郊环境中的红树林：蒙巴萨案例（肯尼亚）
DOI：
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发表时间：
2009
影响因子：
1.8
通讯作者：
N. Koedam
中科院分区：
文献类型：
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作者：
M. Mohamed;G. Neukermans;J. Kairo;F. Dahdouh;N. Koedam
在Kombeni和Tsalu两个森林样地的带样带上研究了蒙巴萨都铎河近郊红树林植被的结构和更新模式。从物种重要性值来看，红树林优势种为麻根草。（根参科）和海棠（Forssk.）Vierh。(Avicenniaceae)。总状光虫。在较早的植物区系调查报告中没有发现。乔木密度从贡贝尼的1,264棵ha-1到查鲁的1,301棵ha-1，平均树高在前者高于后者。两个地点的大小级结构均表现出小树在数量上的优势。成树和幼树的空间分布格局在不同的地点差异很大，成树表现出接近均匀分布（森下指数Iδ≪1），而幼树则有聚集分布的趋势（Iδ≠1）。本文表明，未被管理但被开发的城郊红树林在结构上受到压力，具有扩大的冠层间隙，其特征是影响再生的空间和时间站点异质性，这意味着冠层关闭的时间更长。使红树林产品的用途多样化，并建立保护区作为禁伐区，规范采伐，将最大限度地减少树冠间隙的大小，并促进保护措施。从长远来看，所提出的管理策略将提高城市周边生态系统对人为和自然压力源的适应能力。
The structure and regeneration patterns of the peri-urban mangrove vegetation of Mombasa at Tudor creek were studied along belt transects at two forest sites of Kombeni and Tsalu. Based on the species importance values, the dominant mangrove species were Rhizophora mucronata Lam. (Rhizophoraceae) and Avicennia marina (Forssk.) Vierh. (Avicenniaceae). Lumnitzera racemosa Willd., reported in an earlier floristic survey, was not encountered. Tree density varied from 1,264 trees ha–1 at Kombeni to 1,301 trees ha–1 at Tsalu and mean tree height was higher at the former site compared to the latter. The size-class structure at both localities showed the numerical dominance of small trees over larger trees. The spatial distribution pattern of adults and juveniles varied greatly between sites and showed a close to uniform pattern (Morisita’s Index Iδ ≪ 1) for adult trees, but a tendency to clustered distribution (Iδ ≫ 1) for juveniles. The present paper shows that unmanaged but exploited peri-urban mangroves are structurally stressed, having enlarged canopy gaps that are characterised by spatial and temporal site heterogeneity that influences regeneration, implying longer periods for canopy closure. Diversifying uses of mangrove products and establishing reserves as no cut zones with regulated harvesting will minimise canopy gap sizes, and promote conservation practices. The proposed management strategy shall boost the ecosystem resilience to both anthropogenic and natural stressors expected in the peri-urban setting in the long run.