Page 103 - 《广西植物》2026年第1期
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1 期              邱思婷等: 濒危海草贝克喜盐草生物量的时空变化及其关键影响因素                                             9 9

                 Abstract: To enhance the understanding of biomass distribution and its driving factors in the threatened seagrass
                 Halophila beccarii along the South China coastꎬ this study systematically investigated the spatiotemporal dynamics of its
                 biomass and key environmental variables across six regions (Huachangwanꎬ Yangpuꎬ Shajingꎬ Tangjiawanꎬ Yifengxiꎬ
                 and Zhaoan)ꎬ located in four coastal provinces (regions) of South China. Seasonal field sampling was conducted to
                 capture intra ̄annual variations. The results were as follows: (1) The mean abovegroundꎬ belowgroundꎬ and total
                                                            ̄2                                       ̄2
                 biomass values of H. beccarii were (11.98 ± 13.06) gm DW (x±sꎬ the same below)ꎬ (12.06 ± 12.96) gm DW ꎬ
                                       ̄2
                 and (24.05 ± 23.70) gm DWꎬ respectivelyꎬ in which biomass at Tangjiawan was significantly lower than that at
                 other research sites (P<0.05). Distinct seasonal patterns were observedꎬ with lower biomass during winter and spring
                 and higher values in summer and autumn. (2) Except for pH and nitriteꎬ all other environmental factors ( water
                 temperatureꎬ salinityꎬ inorganic phosphorusꎬ nitrateꎬ and ammonia nitrogen ) differed significantly among sites (P<
                 0.05)ꎬ indicating substantial spatial heterogeneity in habitat conditions. ( 3) Correlation analyses revealed that
                 aboveground biomass was significantly positively correlated with water temperature and inorganic phosphorus (P<0.05)ꎬ
                 and negatively correlated with ammonia nitrogen ( P < 0. 05). Belowground biomass was positively correlated with
                 inorganic phosphorus and nitrate (P<0.05). Total biomass showed positive correlations with inorganic phosphorus and
                 nitrate (P<0.05)ꎬ and a negative correlation with ammonia nitrogen (P<0.05)ꎬ suggesting that both nutrient availability
                 and temperature play key roles in regulating productivity. (4) Principal component analysis (PCA) result showed that
                 water temperature and nitrite were the main positive factors affecting total biomassꎬ whereas ammonia nitrogen exhibited
                 an inhibitory effectꎬ underscoring the importance of nutrient balance and thermal environment. (5) Linear regression
                                                       2
                 further confirmed a significant linear relationship (R = 0.118ꎬ P<0.001) between pore water physicochemical factors
                 and total biomassꎬ indicating that other unmeasured variables may also influence biomass variability. The results of this
                 study have important scientific value for understanding the ecological characteristicsꎬ environmental adaptation
                 mechanismꎬ and causes of endangerment of H. beccariiꎬ and offer a theoretical foundation for its conservation and
                 management of this species.
                 Key words: Halophila beccariiꎬ biomassꎬ pore water physicochemical factorsꎬ multivariate statistical analysisꎬ South
                 China coast



                海草是广泛分布于温带和热带海域的沉水性                            弱性而 被 世 界 自 然 保 护 联 盟 ( International Union
            被子植 物ꎬ 通 常 生 长 在 潮 间 带 和 潮 下 带 浅 水 区               for Conservation of Natureꎬ IUCN) 列 为 濒 危 物 种
            (Short et al.ꎬ 2007)ꎮ 海草具有较高的初级生产                  (Short et al.ꎬ 2011)ꎮ 贝克喜盐草是水鳖科喜盐草
            力ꎬ既能通过食物链与碎屑循环为浅海生态系统                              属的海草植物ꎬ形态小ꎬ雌雄同株ꎬ有一年生和多
            提供营养和能量ꎬ又能将营养物质( 氮、磷) 和有机                          年生生 活 史ꎬ 生 长 快ꎬ 种 群 变 化 大 ( 邱 广 龙 等ꎬ
            碳传送到海洋深处( Duarte & Dorteꎬ 2017)ꎬ为海                 2020ꎻGeng et al.ꎬ 2022)ꎮ 多生长于受人为活动影
            洋“蓝碳”作出了重要贡献( Mcleod et al.ꎬ 2011)ꎮ                响较 大 的 潮 间 带ꎬ 偏 好 淤 泥 或 泥 沙 底 质 生 境
            此外ꎬ海草还能通过削弱波浪能量、捕获沉积物和                             (Kumar & Deepakꎬ 2021)ꎮ 据报道ꎬ全球贝克喜盐
            调节养分循环等机制来保护海岸线ꎬ同时还能作                              草主要分布于马来西亚、泰国、新加坡、印度和中
            为沿海污染的生物指标( Lewis & Richardꎬ 2009ꎻ                 国等亚洲国家和地区( Short et al.ꎬ 2011)ꎬ在中国
            Ondiviela et al.ꎬ 2014ꎻ Costanza et al.ꎬ 2017)ꎮ 尽  则集中分布于广西、广东、福建和海南 4 省( 区)
            管海草在生态系统功能方面很有价值ꎬ但与珊瑚                              (黄向 旭 等ꎬ 2010ꎻ 邱 广 龙 等ꎬ 2013ꎻ 陈 石 泉 等ꎬ
            礁和红树林相比ꎬ其在科研、管理和保护方面未受                             2015ꎻ钟超等ꎬ2024)ꎮ

            到国际和国内社会的足够关注( Kumar & Deepakꎬ                         生物量是能量流动和物质循环的基础ꎬ同时
            2021)ꎮ 并且ꎬ全球气候变化和人类活动引起的沿                          也是衡量生态系统结构与功能的重要指标( 邓筱
            海富营养化和盐度变化等问题ꎬ正加速全球海草                              凡等ꎬ2022)ꎮ 海草在海洋生态系统中扮演着重要
            床的衰退( Waycott et al.ꎬ 2009)ꎮ 在众多海草物                角色ꎬ其生物量是衡量海草生态系统结构和功能
            种中ꎬ贝克喜盐草( Halophila beccarii) 因其生境脆                的关键指标ꎬ直接反映了该生态系统的健康状况
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