黄河下游营养盐浓度月际变化及其对水库泄洪事件的响应

根据2017年12月—2019年12月和2018年小浪底水库泄洪期间对黄河下游营养盐的月观测和日观测,系统的分析了黄河下游溶解态营养盐浓度、组成和通量变化。结果表明,除DON(溶解有机氮)、DSi(溶解态硅)和DIP(溶解无机磷)外,其他各溶解态营养盐浓度均呈丰水期低、枯水期高的特点。在观测期间,DSi/DIN(溶解态硅/溶解无机氮)比值月变化呈升高趋势,而DIN/DIP和DSi/DIP比值呈降低的趋势,可能与近年来黄河流域生态环境变化有关。水库泄洪期间DIN和DSi浓度升高,主要与水库下泄高浓度营养盐水体和大径流冲刷沿岸土壤导致营养盐释放进黄河水体有关;DIP和DOP(溶解有机磷)浓度降低,主要受到大径流稀释和悬浮颗粒物吸附作用的影响。水库泄洪期间DSi/DIP与DSi/DIN比值增加,而根据水体富营养化潜力指标(ICEP)显示,水库泄洪的年份P-ICEP和N-ICEP均高于非水库泄洪的年份数倍,进一步证明水库泄洪事件会加剧营养盐失衡,潜在影响黄河口及其邻近海域浮游植物群落结构。2018年水库水沙调控期间输送了全年各项营养盐入海通量的13%～25%,在全年营养盐输送通量中扮演重要的角...     

2019年夏秋季温州近海海水透明胞外聚合颗粒物（TEP）的分布及影响因素分析

透明胞外聚合颗粒物（TEP）具有高黏性、低密度和高碳氮比等特性,在颗粒有机物的聚集以及食物网循环中发挥着重要作用。为了解近岸海域TEP的分布动力学规律与机制,本文对温州近海夏秋季节水体中透明胞外聚合颗粒物的分布进行调查,并结合多项环境要素的主成分分析与相关性分析,探究了浙江南部近岸海域TEP分布的影响因素。结果显示,温州近海TEP秋季平均含量明显高于夏季,夏季TEP分布变化主要受陆地径流（瓯江）作用影响,而秋季主要受闽浙沿岸流影响。受沿岸流影响,秋季TEP的主要来源可能是其他海域以及底层颗粒物再悬浮。此外,由浮游植物释放的TEP对夏季的POC贡献最大,而秋季外源性TEP对POC的贡献较夏季有所升高。     

海草光学遥感监测研究综述

海草生长在热带、亚热带和温带海洋水域, 是全球海洋生态系统中重要的结构和功能组成部分, 具有极高的生态服务价值。由于受到人类活动和自然灾害的强烈影响, 海草正在全球范围内快速衰退, 因此开展海草资源监测与保护具有非常重要的意义。随着传感器技术的发展, 光学遥感在海草监测中表现出卓越优势。本文综述了国内外海草遥感监测研究现状, 重点总结了研究内容、技术和方法, 论证了海草光学遥感监测的可行性, 旨在为我国海草光学遥感监测厘清适宜数据和可靠技术方法, 并指明潜在研究方向。同时也希望能为海草遥感监测提供借鉴, 并拓展海草资源科学管理的思路。     

海岸侵蚀作用下海岸带地区极端风暴洪水风险评估 —以上海石化为例

海堤是海岸带地区社会经济活动的重要保护屏障。海岸侵蚀的加剧将导致海堤稳定性和安全性降低, 增加海岸带地 区遭受极端风暴洪水的风险, 进而影响到海岸带地区的安全。本文选择上海石化这一遭受海岸侵蚀较为严重的区域作为研究 区, 利用 GIS 分析了 1972—2020 年近岸海床侵蚀特征, 并基于 2000—2020 年-5 m 等深线变化评估了上海石化近岸海堤的 稳定性。结果表明： 1972—2020 年间上海石化前沿海床整体以侵蚀为主, 石化近岸东侧以及西侧局部的浅滩侵蚀明显, 城 市沙滩中段、第 6 次围堤处以及码头东岸海堤稳定性最低。基于上述研究结果, 考虑海堤稳定性薄弱段出现极端风暴洪水漫 堤或溃堤情景, 模拟并分析了上海石化 2010 年 、2030 年和2050 年遭受千年一遇极端风暴洪水的风险。结果显示： 在 2010 年基准年情景下, 受海岸侵蚀作用最明显的城市沙滩和第6 次围堤区域遭遇极端风暴洪水的风险最高, 到 2050 年, 当前稳 定性较好的海堤安全性也将大大降低, 与 2010 年相比, 上海石化近岸地区的直接经济损失将会增加近 3 倍。     

Porewater-derived dissolved inorganic carbon and nutrient fluxes in a saltmarsh of the Changjiang River Estuary

Saltmarshes are one of the most productive ecosystems, which contribute significantly to coastal nutrient and carbon budgets. However, limited information is available on soil nutrient and carbon losses via porewater exchange in saltmarshes. Here, porewater exchange and associated fluxes of nutrients and dissolved inorganic carbon(DIC) in the largest saltmarsh wetland(Chongming Dongtan) in the Changjiang River Estuary were quantified. Porewater exchange rate was estimated to be(37±35) cm/d during December 2017 using a radon(~(222)Rn) mass balance model. The porewater exchange delivered 67 mmol/(m~2·d), 38 mmol/(m~2·d) and 2 690 mmol/(m~2·d) of dissolved inorganic nitrogen(DIN), dissolved silicon(DSi) and DIC into the coastal waters,respectively. The dominant species of porewater DIN was NH_4~+ (99% of DIN). However, different with those in other ecosystems, the dissolved inorganic phosphorus(DIP) concentration in saltmarsh porewater was significantly lower than that in surface water, indicating that saltmarshes seem to be a DIP sink in Chongming Dongtan. The porewater-derived DIN, DSi and DIC accounted for 12%, 5% and 18% of the riverine inputs, which are important components of coastal nutrient and carbon budgets. Furthermore, porewater-drived nutrients had obviously high N/P ratios(160–3 995), indicating that the porewater exchange process may change the nutrient characteristics of the Changjiang River Estuary and further alter the coastal ecological environment.     

中国近海裸甲藻中文名的研究

通过研究在中国近海海域鉴定出25种裸甲藻,但发现其中许多种的中文名在国内文献中不统一,不规范,有些甚至曲解了有效拉丁名的原意。该研究对中文名使用不规范、争议较多或者在国内尚未报道过的共13种裸甲藻的发现历史,拉丁属名与种名的确立以及修定过程做出描述,结合有效拉丁名的中文释义和物种的形态特征,按照具体的中文名修订与命名原则,给出一个科学的、能准确表明其分类地位的中文种名。另外12种裸甲藻的中文名在国内的使用相对准确且较统一,最后将25种中国近海裸甲藻的有效拉丁名以及中文名进行了汇总。     

我国近岸海域富营养化评价新方法及应用

参考目前国际上被广泛应用的第2代富营养化评价方法体系,结合我国近岸海域生态环境特点和监测资料现状,建立了一种以压力-状态-响应模式为基本框架、以富营养化症状为主的第2代近岸海域富营养化评价体系。实际应用结果表明,应用本方法得出的长江口海域富营养化状况评价结论,与目前国外主流评价方法的评价结论一致,而且本方法具有评价指标代表性强、数据资料易得、评价标准有据、方法简便易行等优点。     

Physical habitat and social conditions across a coral reef shape spatial patterns of intraspecific behavioral variation in a demersal fish

As coral reef ecosystems decline in health worldwide, reef‐associated fishes are being impacted by changes to their coral reef habitats. While previous studies have shown coral reef structure to affect the demography of reef fishes, changes in reef conditions may also impact the behavior of reef fishes as they cope with altered habitats. In this study, we examined spatial patterns of intraspecific behavioral variation in the bicolor damselfish (Stegastes partitus) across the fringing reefs of Curaçao (Caribbean Sea), and explored how this behavioral variation associated with physical and social conditions on the reef. Principal components analysis (PCA) condensed physical parameters of the reef into principal component 1 (PC1), comprising depth, coral cover (%), rugosity, and average hole size (cm²), and principal component 2 (PC2), which represented the number of holes. PC1, but not PC2, increased spatially across the reef as the habitat transitioned from coral rubble in the shallows to live coral on the reef slope. This transition in reef structure was paralleled by changes in social conditions including decreases in bicolor damselfish density in habitats with higher PC1 values. The behavior of bicolor damselfish also varied spatially with greater aggression and more frequent shelter use in habitats with lower PC1 values. Path analysis revealed robust associations between this behavioral variation and physical habitat conditions of the reef, indicating that physical – rather than social – habitat variation is the primary determinant of these spatial patterns of intraspecific behavioral variation. Taken as a whole, this coupling between physical reef structure and behavior suggests that reef fish may show altered behaviors on coral reefs degraded by anthropogenic impacts.     

Interaction of an anticyclonic eddy with sea ice in the western Arctic Ocean: an eddy-resolving model study

The dramatic decline of summer sea ice extent and thickness has been witnessed in the western Arctic Ocean in recent decades, which hasmotivated scientists to search for possible factors driving the sea ice variability. An eddy-resolving, ice-ocean coupled model covering the entire Arctic Ocean is implemented, with focus on the western Arctic Ocean. Special attention is paid to the summer Alaskan coastal current (ACC), which has a high temperature (up to 5℃ ormore) in the upper layer due to the solar radiation over the open water at the lower latitude. Downstream of the ACC after Barrow Point, a surface-intensified anticyclonic eddy is frequently generated and propagate towards the Canada Basin during the summer season when sea ice has retreated away from the coast. Such an eddy has a warm core, and its source is high-temperature ACC water. A typical warm-core eddy is traced. It is trapped just below summer sea ice melt water and has a thickness about 60 m. Temperature in the eddy core reaches 2-3℃, and most water inside the eddy has a temperature over 1℃. With a definition of the eddy boundary, an eddy heat is calculated, which can melt 1 600 km² of 1mthick sea ice under extreme conditions.     

厦门海域鱼类群落分类学多样性的研究

根据厦门海域鱼类种类组成历史资料和调查资料,系统整理了厦门海域的鱼类总名录和现有名录,并应用分类学等级多样性指数和分类差异变异指数分析了厦门海域鱼类群落分类学多样性的时空变化。结果表明:厦门海域有记录鱼类共649种;现有鱼类有331种,隶属2纲22目90科181属,其中软骨鱼纲共5目9科9属15种,辐鳍鱼纲共17目81科172属316种。厦门海域鱼类总名录的等级多样性指数Δ+和分类差异变异指数Λ+分别为79.267和220.96;现有鱼类群落分类多样性指数Δ+和分类差异指数Λ+分别为77.504和245.34。分类多样性指数Δ+在冬、春季较高,秋季次之,而夏季最低;而分类差异指数Λ+夏季较高,秋季次之,冬春季较低。秋季和冬季鱼类组成的相似度最高,其次为夏季,最后为春季。与历史总名录相比,厦门海域的现有鱼类群落分类学范围较小,生态幅变窄,群落稳定性较差。