Historical changes in seagrass beds in a rapidly urbanizing area of Guangdong Province: Implications for conservation and management
Historical changes in seagrass beds in a rapidly urbanizing area of Guangdong Province: Implications for conservation and management
复制标题
广东省快速城市化地区海草床的历史变化：对保护和管理的影响
DOI：
10.1016/j.gecco.2020.e01035
复制
发表时间：
2020-06-01
影响因子：
4
通讯作者：
Huang, Xiaoping
中科院分区：
文献类型：
--
作者：
Jiang, Zhijian;Cui, Lijun;Huang, Xiaoping
快速的城市化导致海草床加速减少。对广东省快速城市化地区海岸线上沿着分布的海草床状况进行了研究，以记录海草床的变化，并探讨海草特性及其可塑性的决定因素。新发现海草床13个，总面积679.04公顷，已知海草床11个，从972.55公顷减少到858.67公顷，其中7个海草床在近10年内消失，主要原因是人工岸线和海滩坝的建设加剧，养鱼和虾池养殖、牡蛎养殖、种植红树林及收集贝壳类海产。占最大床的Halophila ovalis的叶氮含量从2011年的（2.09 +/- 0.24）%增加到2017年的（3.39 +/- 0.18）%，表明富营养化加剧。贝氏嗜盐藻生长的最适海水溶解性无机氮和溶解性无机磷浓度分别为40 μ mol/L和2.5 μ mol/L。H.贝卡氏菌与沉积物泥质含量呈正相关。在低盐条件下，叶片更长、更宽，地上和地下生物量也更大，表明H。贝卡利虫喜欢低盐环境。高密度枝条可引起种内竞争，进而导致自疏。beccarii，导致叶面积、地上和地下生物量以及根长度减少。因此，长期监测海草床沿着广东省迅速城市化的海岸线，需要解开下降的机制，并制定有效的管理策略。(C)2020年，任作家。由爱思唯尔公司出版
Rapid urbanization leads to an accelerating decline of seagrass beds. The status of seagrass beds along the entire coastline of a rapidly urbanizing area, Guangdong Province, was examined to document the change in seagrass beds and to explore the determinants of seagrasses characteristics and their plasticity. Thirteen seagrass beds were newly discovered with a total area as 679.04 ha, whereas eleven known seagrass beds have decreased from 972.55 ha to 858.67 ha with seven of them having disappeared in recent decade primarily due to exacerbated construction of artificial shorelines and beach dams, increased nutrient inputs from fish caging and shrimp pond culture, oyster culture, mangrove planting and shellfish collection. The leaf nitrogen content of Halophila ovalis, which dominated the largest beds, increased from (2.09 +/- 0.24)% in 2011 to (3.39 +/- 0.18)% in 2017, indicating enhanced eutrophication. The optimum seawater dissolved inorganic nitrogen and dissolved inorganic phosphorus levels for Halophila beccarii were 40 mu mol/L and 2.5 mu mol/L, respectively. The standing stock and plant dimensions of H. beccarii were positively correlated with sediment mud content. Longer, wider leaves, and greater aboveground and belowground biomass were observed at lower salinities, indicating that H. beccarii prefers hyposaline habitats. High shoot density could induce intraspecific competition followed by self-thinning in H. beccarii, leading to reduced leaf area, aboveground and belowground biomass, and root length. Thus, long-term monitoring of seagrass beds along the rapidly urbanizing coastline of Guangdong Province is needed to unravel the mechanisms of decline and to develop effective management strategies. (C) 2020 The Authors. Published by Elsevier B.V.