广东沿海海草床的现状、面临的威胁与保护建议

Status,threats and conservation suggestions on seagrass beds in Guangdong

海草床是地球上最具价值的生态系统之一,为人类提供广泛的生态系统服务。我国乃至全球范围内海草床面临着人类活动威胁,且呈退化趋势。广东海草研究起步较晚,近年来涌现的一些研究成果将广东海草分布特征清晰地呈现在世人面前,并发现海草床受到的威胁来源多样,但缺乏系统的总结。基于广东滨海地区未来一段时间将持续面临高强度人类活动压力的背景下,为有效保护海草床及其生物多样性,亟需进一步深入了解广东海草床存在的问题,从而提出针对性的保护建议。本文通过回顾21世纪以来广东海草床研究成果,汇总了广东海草分布信息,并结合现场调研和国内外海草床的研究报道,梳理了广东海草床面临的威胁。结果表明广东沿岸海草分布广泛,现有海草床面积约1,540ha。海草种类共5种,以卵叶喜盐草(Halophilaovalis)和贝克喜盐草(H.beccarii)为主,日本鳗草(Zosterajaponica)、单脉二药草(Haloduleuninervis)和短柄川蔓草(Ruppia brevipedunculata)分布较少。本文阐明了人为因素和自然因素如何影响海草的生长和分布,并指出了广东海草床主要面临着海水养殖、渔业捕捞、陆源污染、海洋工程等人类活动的威胁。此外,物种入侵和全球气候变化的影响也不容忽视。针对上述威胁,在现有的保护基础之上,建议加强海草床生态系统研究、提升海草调查监测能力、建立健全海草保护监管体系、管控污染物排放、强化海草床生态修复并开展海草科普宣传等工作。

Background&Aims:Seagrass beds rank among the earth’s most valuable ecosystems,providing extensive ecosystem services to human.Despite their global significance,seagrass beds in the world,particularly in China,face threats from human activities,leading to their degradation.While recent studies in Guangdong Province have increasingly elucidated the distribution characteristics of seagrass beds and threats from multiple sources,a systematic summary of these findings remains limited.Given the anticipated continued pressure of high intensity human activities in the future period of time along the Guangdong coast,a deeper understanding of the challenges faced by seagrass beds in crucial from formulating targeted conservation suggestions aimed at effectively preserving their biodiversity.Review results:In this work,we comprehensively reviewed research results on Guangdong seagrass beds since the 21st century and summarized the information on their distribution of seagrass beds.Through a combination of field investigations and domestic and international research,we identified to Guangdong seagrass beds.The results showed that seagrass was widely distributed along the Guangdong coast,covering an area of 1,540 ha and comprising five species.Halophila ovalis and H.beccarii were both dominant species,while Zostera japonica,Halodule uninervis,Ruppia brevipedunculata had more limited distribution.This paper illustrated the impact of both human and natural factors on growth and distribution of seagrass,and pointed out that human activities such as mariculture,fishing,land-based pollution,marine engineering as primary threats.Moreover,the study acknowledged the significance of species invasion and global climate change.Perspectives:Aiming at threats mentioned above,we proposed conservation suggestions that building upon established protection measures.These recommendations include strengthening scientific research on seagrass bed ecosystem,improving the ability of survey and surveillance on seagrass,establishing a regulatory system for protecting seagrass,managing and controlling pollutant emissions,reinforcing ecological restoration of seagrass beds,and launching popular science activities and awareness campaigns.