Coastal Ecosystem Health Research Articles

High-Resolution Mapping Changes in the Invasion of Spartina Alterniflora in the Yellow River Delta

The propagation of the invasive <i>Spartina alterniflora</i> (<i>S. alterniflora</i>) has seriously affected the health of coastal wetland ecosystems in China and thus requires an urgent response. In this research, we construct a feature vector set containing phenological and other time-series features based on the Google Earth Engine (GEE) platform by combining dense time-series images from the Sentinel-1 and Sentinel-2 satellites. We obtained the dataset of the annual distribution of <i>S. alterniflora</i> in the Yellow River Delta (YRD) from 2016 to 2021 by developing an object-oriented random forest classification model. The results show that <i>S. alterniflora</i> has different phenological features from other wetland plants that played an important role in its classification based on the images. A combination of multiple phenological and temporal features improved the classification accuracy of <i>S. alterniflora</i> (multi-year average OA: 95.38&#x0025;; UA: 95.01&#x0025;; PA: 95.17&#x0025;). Our results suggest that from 2016 to 2021, the growth rate of the area occupied by <i>S. alterniflora</i> was 2.17 km² per year, and a new patch of the <i>S. alterniflora</i> appeared in the south of the study area in 2018. The work here provides scientific data to support the monitoring and control of the invasive <i>S. alterniflora</i> at a large scale.

Effects of nitrogen on the longitudinal and vertical patterns of the composition and potential function of bacterial and archaeal communities in the tidal mudflats

Increasing attention has been focused on the diminishing health of coastal ecosystems. Understanding the effects of eutrophication on tidal flat ecosystems is beneficial for the restoration and management of coastal ecosystems. However, previous studies did not consider the effects of nitrogen on the structure and function of bacterial and archaeal communities in longitudinal and vertical profiles. Here, the diversity, composition, assembly mechanism, and potential metabolic function of the bacterial and archaeal communities were studied in two longitudinal tidal sections at different eutrophic levels. Nitrogen and salinity were the critical factors that influenced the bacterial and archaeal community composition using canonical correspondence and multivariate regression tree analyses. For the bacterial community, the higher nitrogen loading in tidal mudflats resulted in the convergence of diversity and structure in the longitudinal profile of bacteria, but divergence was detected in the vertical profile. For archaea, the diversity tended to be convergent in longitudinal and vertical profiles in the higher nitrogen area, but the change of structure was similar to that of bacteria. Besides the homogeneous processes influenced by salinity, the assembly process of the bacterial community was mainly influenced by heterogeneous selection (34.8%) and that of archaea by dispersal limitation (19.5%). However, the bacterial and archaeal communities in the higher nitrogen section presented more of an influence of heterogeneous selection (respectively, 39 and 5.6%) than that of the lower nitrogen section (respectively, 10 and 0.2%). Structural equation modeling indicated that nitrogen may have inhibited the effects of the bacterial community on nitrogen turnover in nitrogen-rich anoxic sediment environments, but may have strengthened the effect of the archaeal community on carbon metabolism compared to bacteria. This work deepens our understanding of the responses of bacterial and archaeal community structure and potential function to nitrogen pollution in tidal mudflats.

Multiple pollutants stress the coastal ecosystem with climate and anthropogenic drivers

Coastal ecosystem health is of vital importance to human well-being. Field investigations of major pollutants along the whole coast of China were carried out to explore associations between coastal development activities and pollutant inputs. Measurements of target pollutants such as PFAAs and PAHs uncovered notable levels in small estuary rivers. The Yangtze River was identified to deliver the highest loads of these pollutants to the seas as a divide for the spatial distribution of pollutant compositions. Soil concentrations of the volatile and semi-volatile pollutants showed a cold-trapping effect in pace with increasing latitudinal gradient. The coastal ecosystem is facing high ecological risks from metal pollution, especially copper (Cu) and zinc (Zn), while priority pollutants of high risks vary for different kinds of protected species, and the ecological risks were influenced by both climate and physicochemical properties of environmental matrices, which should be emphasized to protect and restore coastal ecosystem functioning.

Distribution and Flora of Seaweed Beds in the Coastal Waters of China

Seaweed plays an important role in energy production in marine, coastal, and island ecosystems. The protection of seaweed beds is a key point for coastal ecosystem health, but the community characteristics, dominant species, and distribution of seaweed beds in the coastal waters of China are still unknown. Dividing seaweed beds based on their ecological function is also required for coastal ecosystem conservation, marine development, and utilization. We conducted ecological surveys on various types of ecosystems at approximately 50 sites dedicated to the conservation of seaweed bed biodiversity in China from 2018 to 2019. These seaweed beds were classified into different flora by water temperature and the attributes of the dominant species. The study showed that Sargassum dominated the coast of China. The coverage of the genus Undaria and the genus Laminaria in the coastal waters of Liaoning and Shandong was high and gradually decreased from Zhejiang to the south. The mean biomass of the seaweed beds along the coast of China was 7.29 kg/m2, and the mean coverage was 41.25%. The height and fresh weight of the dominant species gradually decreased with the decreasing latitude. The seaweed beds were distributed from the shallow water zone to the profundal zone along the coast from north to south, and the bathymetry of seaweed beds in Hainan was below 6 m. Based on the water temperature, the attributes of the seaweed beds, the temperature attributes of the dominant species, and the seaweed’s distribution, the seaweed beds in China can be specifically divided into temperate warm water types, subtropical warm water types, and tropical warm water types. This study is relevant to the development of regulations and directives to ensure biodiversity conservation and environmental sustainability.

Tidal creeks as hot-spots for hydrological exchange in a coastal landscape

Coastal ecosystem health and sustainability is tightly coupled to submarine groundwater discharge (SGD) and associated nutrient, carbon and pollutant fluxes. However, there are few studies that systematically analyse the interaction between the terrestrial aquifer system, catchment morphology and coastal SGD. The objective of this study was to evaluate the role of catchment morphology and how this influences the spatial distribution, timing and volume of the SGD flux to a branched tidal creek system, on the barrier island Spiekeroog, Germany. The subsurface salinity was mapped using electrical resistivity tomography (ERT) and a hydrogeochemical survey of the shallow groundwater. Temporal and spatial analysis of geochemical tracers (radon-222, chloride) in the tidal creek water was integrated into a transient 222Rn mass balance model for quantification of SGD rates during two field campaigns that encompassed spring and neap tides. The ERT mapping indicated that fresh groundwater dominated under the dune ridges down to about 15 m depth, but became progressively more brackish seawards. This is likely due to frequent tidal and storm flooding of low-lying areas. The highest groundwater fluxes into the creek were indicated by high 222Rn activities (average 468 Bq m−3) towards the dune ridge. Chloride concentrations (up to 17.3 g L−1) increased seawards showing the progressive salinization of water in the creek. The freshwater component of SGD was highly variable in time but was highest at low tide, while the total SGD flux (saline + fresh) was highest when tides changed from inflow to outflow as the rapid pressure release on the local aquifer caused a large hydraulic gradient towards the creek. Comparing the freshwater component of mean daily SGD to the creek with estimated groundwater recharge rates in the catchment (665 m3 d−1) shows that the fresh groundwater discharge exceeds fresh recharge during spring tides (~120%) but is was lower than recharge during neap tides (~27%). In this study we show that tidal creeks and their relation to catchment morphology are relevant for understanding the spatial and temporal exchange of fresh and saline water between the catchment and coastal zone.

Ostracods as pollution indicators in Lap An Lagoon, central Vietnam.

Southeast Asia is particularly susceptible to the negative impacts of increasing coastal pollution as coastal populations and cities grow at unprecedented rates. Although water chemistry can be monitored, there are greater advantages in using bioindicators as reflectors of the combined effect of multiple pollution types on coastal ecosystem health and for early detection of the negative impacts of pollutants on biotic systems. This study explores the utility and application of ostracods as pollution bioindicators and examines the response of ostracod assemblages to variable pollution in Lap An Lagoon, central Vietnam. From 14 sites within the lagoon, 79 species of 46 genera were identified and sediment grain size, total organic carbon, organic matter and heavy metal concentration were measured. Cluster analysis, detrended correspondence analysis and canonical correspondence analysis identified four distinct ostracod biofacies that were highly correlated to the physical environmental variables (salinity, depth, sediment type, heavy metal concentrations, total organic carbon and organic matter) and are shown to be the main factors controlling ostracod biofacies. Low ostracod diversities were found in silty sediments with heavy metal concentrations likely toxic. Sinocytheridea impressa was indicative of a marginally polluted environment within the lagoon. This study provides evidence for the potential for Southeast Asian ostracods to be used in water quality assessments and the data collected can be used as a baseline for future pollution monitoring.

On the Problem of Modeling the Boat Wake Climate: The Florida Intracoastal Waterway

AbstractQuantifying and forecasting the impact of boat traffic on the health of coastal ecosystems must account for the multiscale nature of the process: from minutes (individual wakes), to days (tidal phase), weeks, and longer (tide modulation, seasonal traffic). Direct numerical simulations covering all these scales are difficult, not in the least because specifying the vessel type and navigation characteristics for every wake is practically impossible. To overcome this problem, we propose a statistical‐mechanics description of the wake field that focuses on classes of wakes, defined by a set of characteristic parameters, and their joint probability density in the characteristic‐parameter space. Here, we demonstrate the first steps of the approach using existing numerical tools and parametrizations. Because vessel type and navigation characteristics are not available, an investigation of wake parameter space is not possible at this time. Instead, we use the leading‐order Froude‐number parametrization defined by a linear model to classify the wake population observed during the field experiment. Numerical tests applying the FUNWAVE‐TVD model across all wake‐classes identified show excellent skills for weakly dispersive wakes. The model is challenged by the short waves generated by small, slow boats. However, simulations suggest that the problem is confined to the deeper water domain and linear evolution. Nonlinear wake shoaling, essential for modeling wake‐induced sediment transport and wake impact on the environment, is described well.

Using ECHO as a decision support tool to manage coastal systems subject to physical changes

Physical changes in coastal systems, caused by human or natural processes, lead to changes in flow patterns and salinity, temperature and sediment distributions. These changes can affect the health of an ecosystem. This paper demonstrates the use of the model ECHO (coastal ECosystem Health assessment model using Oysters as the indicator species) for the assessment of the impacts on spatial distribution of the oyster zones. ECHO uses outputs of a 3-D hydrodynamic model to delineate zones hospitable to oysters; its outputs are much more concise than the extensive spatial and temporal outputs of the hydrodynamic models typically employed to simulate physical changes in a coastal environment. This study used ECHO to investigate the impacts of two hypothetical physical changes which altered hydrodynamics in a bay; the impacts were determined by examining the changes in the spatial extents of the delineated oyster zones. For the test cases, a region of a decreased water depth results in improved conditions for oysters, whereas adding an increased amount of freshwater inflow to the bay decreases the prevalence of oyster zones throughout the bay. ECHO reveals that the predominant reason for changes in the spatial extents of oyster zones in the latter case is prolonged stratification. By examining the spatial and temporal behavior of shear and density effects, we conclude that the Richardson number is a better means of quantifying stratification in a complicated tidal system than density gradients alone.

The Baltic Health Index (BHI): Assessing the social–ecological status of the Baltic Sea

Abstract Improving the health of coastal and open sea marine ecosystems represents a substantial challenge for sustainable marine resource management, since it requires balancing human benefits and impacts on the ocean. This challenge is often exacerbated by incomplete knowledge and lack of tools that measure ocean and coastal ecosystem health in a way that allows consistent monitoring of progress towards predefined management targets. The lack of such tools often limits capabilities to enact and enforce effective governance. We introduce the Baltic Health Index (BHI) as a transparent, collaborative and repeatable assessment tool. The Index complements existing, more ecological‐oriented, approaches by including a human dimension on the status of the Baltic Sea, an ecosystem impacted by multiple anthropogenic pressures and governed by a multitude of comprehensive national and international policies. Using a large amount of social–ecological data available, we assessed the health of the Baltic Sea for nine goals that represent the status towards set targets, for example, clean waters, biodiversity, food provision, natural products extraction and tourism. Our results indicate that the overall health of the Baltic Sea is suboptimal (a score of 76 out of 100), and a substantial effort is required to reach the management objectives and associated targets. Subregionally, the lowest BHI scores were measured for carbon storage, contaminants and lasting special places (i.e. marine protected areas), albeit with large spatial variation. Overall, the likely future status of all goals in the BHI averaged for the entire Baltic Sea is better than the present status, indicating a positive trend towards a healthier Baltic Sea. However, in some Baltic Sea basins, the trend for specific goals was decreasing, highlighting locations and issues that should be the focus of management priorities. The BHI outcomes can be used to identify both pan‐Baltic and subregional scale management priorities and to illustrate the interconnectedness between goals linked by cumulative pressures. Hence, the information provided by the BHI tool and its further development will contribute towards the fulfilment of the UN Agenda 2030 and its Sustainability Development Goals. A free Plain Language Summary can be found within the Supporting Information of this article.

Climate Change, South Asia and Southeast Asian Region

It is well known that the climatic conditions of our earth have changed since its origin. In its early days environmental conditions were not suitable for life. However, with due course of time it has changed and origin of life took place. Scientists have found seven cycles of glacial advance and retreat during the last 650,000 years and also that the last ice age abruptly ended about 7,000 years ago. The phenomenon of climate change has many implications and immense effects on our environment. There are many factors such as emissions of greenhouse gases, deforestation, urbanization and industrialization which impact the climate. Some of the major consequences of climate change include impacts on sea level rise in coastal areas, impacts on forestry, agriculture and food productivity, life and property in coastal areas, marine life, wildlife habitat and natural ecosystem, biodiversity, glaciers, floods and human health. This paper is an attempt to understand the phenomenon of climate change, historical evidences of climate change, identify reasons of global warming and climate change and its consequences in the South Asia and, in its neighbouring regions.

A place for subterranean estuaries in the coastal zone

Willard S. Moore coined the term subterranean estuary (STE) as that part of the coastal aquifer ‘where groundwater derived from land drainage measurably dilutes seawater that has invaded the aquifer through a free connection to the sea’ more than two decades ago (Moore, 1999). In doing so, Moore was calling attention to the potential importance of this zone, long studied by terrestrial hydrologists, to marine systems. Since then, we have accumulated indisputable evidence of the importance of STEs and their associated submarine groundwater discharge (SGD) in coastal ecosystem function. Yet, subterranean estuaries are often not considered distinct systems in the land-ocean continuum either from an academic viewpoint or for developing integrative monitoring and management. This invisibility means that the impact of STEs on ecosystem state has been neglected when environmental assessments that aim to meet coastal water quality and ecosystem health targets are performed. It is possible that our current broad definition of STEs, as well as misuse and misunderstanding of terminology, partly explain their de-facto transparency to the wider coastal scientific community. Here, we argue for the inclusion of STEs as important, interconnected systems driving water quality, ecology, and biogeochemical cycles in nearby coastal ecosystems. To achieve broader recognition, we first need to address the perceived compartmentalization of surface and groundwater systems, as well as overcome a pigeon-holed approach to research often confined within narrow disciplinary boundaries. The establishment of open-water estuarine science over the last several decades shows that such obstacles are surmountable. A lack of awareness and recognition of STE functions impedes a holistic understanding of coastal ecosystems and slows down the development of cause-effect relationships for a science-based approach to ecosystem management.

滨海湿地生态系统土壤微生物及其影响因素研究综述

PDF HTML阅读 XML下载 导出引用 引用提醒 滨海湿地生态系统土壤微生物及其影响因素研究综述 DOI: 10.5846/stxb201909201961 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（41230751）；自然资源部公益性行业科研专项（201511086）；浙江省自然科学基金项目（LY19D010007）；自然资源部海岸带开发与保护重点实验室开放课题（2019CZEPK09） Progress and prospect of soil microorganisms and their influencing factors in coastal wetland ecosystem Author: Affiliation: Fund Project: [Foundation: National Natural Science Foundation of China (41230751); Special Funds for Public Industry Research Projects of the Ministry of Natural Resources(201511086); Natural Science Foundation of Zhejiang Province (LY19D010007)] 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:土壤微生物是滨海湿地生态系统中不可或缺的关键组分，在土壤发育、物质循环和污染物净化等诸多土壤生态过程中发挥着重要作用，对滨海湿地生态系统的维持与健康具有重大影响。系统梳理了滨海湿地土壤微生物群落结构特征和多样性，综述了土壤理化性质、植被状况、水文因素、生物入侵、全球变化、湿地开垦、石油污染等因素对滨海湿地土壤微生物的影响。在此基础上，对今后的研究重点提出了4个方面的展望：①加强全球变化多因子交互作用下滨海湿地土壤微生物的响应机制；②强化滨海湿地土壤微生物与环境因子的互作机理；③深化滨海湿地水动力条件对土壤微生物的影响机制；④开展土壤微生物与滨海湿地生态系统物质循环综合研究。研究以期为滨海湿地生态系统的保护和修复提供参考。 Abstract:As an indispensable component in coastal wetland ecosystem, soil microorganisms play an important role in many soil ecological processes, such as soil development, material circulation and pollutant purification, and have a significant impact on the maintenance and health of coastal wetland ecosystems. In this paper, the structure and diversity of soil microbial community in coastal wetlands were systematically reviewed, and the effect of influencing factors such as soil physicochemical properties, vegetation status, hydrological status, biological invasion, global change, wetland reclamation, and oil pollution on soil microorganisms in coastal wetlands were summarized. On this basis, four perspectives are proposed for the future research: 1) strengthening the response mechanism of soil microorganisms in coastal wetland under the interaction of multiple factors of global change; 2) strengthening the interaction mechanism of soil microorganisms and environmental factors in coastal wetland; 3) deepening the influence mechanism of hydrodynamic conditions on soil microorganisms in coastal wetland; and 4) carrying out the comprehensive research on soil microorganisms and material circulation of coastal wetland ecosystem. This study is expected to provide reference for the protection and restoration of coastal wetland ecosystems. 参考文献 相似文献 引证文献

Curcumin ameliorates mercuric chloride-induced liver injury via modulating cytochrome P450 signaling and Nrf2/HO-1 pathway

Environmental mercury is a concern for coastal ecosystem health, and exerts adverse effects on human health. Despite the growing body of evidence showing the hepatoprotective roles of curcumin on mercury, the knowledge between the macroscopic descriptions and the actual mechanism(s) underlying these processes is getting larger remains elusive. Herein, mice received single injection of mercuric chloride (HgCl2) (5 mg/kg body weight) and/or curcumin (50 mg/kg, body weight, p.o.). Firstly, the results showed curcumin could decline HgCl2-induced up-regulated the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Additionally, we also found that curcumin could suppress inflammatory damage, unbalance of trace elements (including sodium, magnesium, kalium, calcium overload), oxidative burst induced by HgCl2, which could be associated with cytochrome P450 (CYP450) signaling. Secondly, we found that curcumin could prevent HgCl2-induced cell death both in vivo and in vitro. Furthermore, curcumin significantly increased the nuclear translocation of nuclear factor E2-related factor 2 (Nrf2) and consequently upregulated the expression of heme oxygenase 1 (HO-1) under HgCl2 treatment. Meanwhile, inhibition of HO-1 by zinc protoporphyria could abolish the cytoprotective effects of curcumin in HgCl2-treated L02 hepatocytes. In conclusion, our data identify that curcumin could enhance Nrf2-mediated HO-1 to upregulate antioxidant ability, which might be associate with CYP450 signaling to suppress liver damage induced by HgCl2. The present study further enriches and perfects the mechanism theory of HgCl2 toxicity and suggest that the CYP450 signaling and Nrf2/HO-1 pathway is important in shedding light on curcumin’s hepatoprotective effects in HgCl2 toxicity.

From ‘clean and green’ to ‘brown and down’: A synthesis of historical changes to biodiversity and marine ecosystems in the Marlborough Sounds, New Zealand

Ecosystem-based management (EBM) is a potential antidote to the alleviation of multiple stressors in highly-valued and contested marine environments. An understanding of the magnitude and drivers of past ecosystem changes can inform the development of realistic ecological and social outcomes for different places. These goals should aim to increase the ecological health and resilience of coastal ecosystems and their connected land- and sea-scapes by minimising anthropogenic disturbances. To address knowledge gaps, we present a marine historical synthesis of the Marlborough Sounds in New Zealand's South Island. These rias are strongly coupled to the surrounding land and inland river catchments. We took an integrated approach by examining effects of land use change on coastal ecosystems, along with case studies of the effects of exploitation on foundational marine species. We found that ecosystems have gone through a series of transformations since Māori settlement ca. 700 years ago, with localised extirpations of marine megafauna, overharvesting of exploited species, and disruption to ecological functioning through ongoing clearfelling of terrestrial and marine biogenic communities since European settlement in the 1800s. There has been a decline from great abundance of marine life to relative scarcity, which is currently evident to local people in increased effort and reduced allowable catches of fish and shellfish. Recovery of biodiversity in the short-term within the Marlborough Sounds is uncertain, given ongoing multiple and interacting stressors from unsustainable land-use and over-exploitation of marine life. Lifting baselines are possible but will require significant changes to land and marine management to restore ecological health and enhance resilience in the face of climate change. Increased marine protection, regeneration of biodiverse biogenic habitats, spatial fishing measures to increase predators of sea urchins, stricter regulation of plantation forestry and a replanting prohibition in critical erosion source areas, are all needed within an EBM framework. Large experimental areas are proposed to develop, test and integrate different management techniques, and to facilitate community understanding, participation, and support for the transition to EBM.

Flow cytometric characterization of the hemocytes of blood cockles Anadara broughtonii (Schrenck, 1867), Anadara kagoshimensis (Lischke, 1869), and Tegillarca granosa (Linnaeus, 1758) as a biomarker for coastal environmental monitoring

Marine bivalves are often used as a sentinel species in coastal environmental monitoring since changes in the environmental quality are often well preserved in their cells and tissues. Anadara and Tegillarca species of Arcidae, the blood cockles, are considered to be good sentinel species in monitoring coastal pollution and ecosystem health because they are distributed widely in the subsurface of intertidal mudflats. Internal cellular defense of the blood cockles to physical and biological stresses is mediated by the circulating hemocytes, while their hemocyte types and functions are poorly studied. In this study, we first characterized morphology and immune-related activities of hemocytes of three common blood cockles Anadara broughtonii, A. kagoshimensis, and Tegillarca granosa using flow cytometry. Based on cell morphology and immunological functions, we described five types of hemocytes identically in the three blood cockles: erythrocytes type-I (erythrocytes-I), erythrocytes type-II (erythrocytes-II), granulocytes, hyalinocytes, and blast-like cells. Erythrocytes were round cells containing hemoglobin with numerous granules in the cytoplasm and these cells consist of two central populations. Erythrocytes-I were the most abundant cells accounting for 80–89% of the total circulating hemocytes and exhibited a certain level of lysosome and oxidative capacity. Erythrocytes-II were the largest cells and displayed high lysosome content and the most active oxidative capacity. Both erythrocytes-I and erythrocytes-II did not show phagocytosis capacity. Granulocytes were intermediated-sized hemocytes characterized by granules in the cytoplasm and long pseudopodia on the cell surface, and these cells were mainly engaged in the cellular defense exhibiting the largest lysosome content, the most active phagocytosis, and high oxidative capacity. Contrary to granulocytes, hyalinocytes were comparatively small and round cells and exhibited no granules in the cytoplasm. Hyalinocytes displayed a certain level of lysosome and phagocytosis and oxidative capacities. Blast-like cells characterized by the smallest size and small quantity of cytoplasm and exhibited an absence of phagocytosis and extremely low oxidative capacity, suggesting that this population is not directly involved in the cell-mediated immune activities. In conclusion, flow cytometry indicated that three blood cockles had five types of hemocytes, and the erythrocytes and granulocytes were mainly involved in the immunological activities.

Stable isotopes used to assess pollution impacts on coastal and marine ecosystems of Cuba and México

Stable isotopes of nitrogen (δ15N) have been widely used around the world to evaluate the impact of anthropogenic activities on marine ecosystems; however, in the Caribbean Sea countries, such as México and Cuba, they are rarely used. Inputs of nutrients related to urban development and tourist activities along the coasts of the Caribbean Sea have the potential to deteriorate their fragile marine ecosystems. The use of isotopic tools and elemental analysis in sentinel organisms would be useful to provide evidence of the impact generated by anthropogenic nutrients. Measurements of δ15N (‰), carbon and nitrogen content, and C:N ratios, were conducted in different sentinel groups (macroalgae, seagrasses, gorgonians, and corals) collected in five marine ecosystems with different nearby coastal development pressure in both countries. The selected ecosystems, ordered according to the level of coastal areas development (low to high), were: Jardines de la Reina (JR), Gulf of Ana Maria (GAM), Cayo Coco (CC), and Laguna Larga (LL) in Cuba, and Puerto Morelos (PM) in México. Results evidenced that the majority of sentinels inhabiting near the most developed coastal areas, in terms of population and tourism, showed higher N contents, lower C:N ratios and higher values of δ15N (e.g., PM and LL) than those near less developed coastal ecosystems (e.g., GAM and JR). Land-based nutrients from municipal wastewater constitute the primary source of N pollution. Because eutrophication represents a significant threat to the integrity of valuable coastal ecosystems, there is an urgent need to accelerate progress in wastewater treatment systems, in terms of capacity and efficiency, to significantly reduce nutrient inputs to coastal ecosystems. Otherwise, more negative changes and deteriorations to the health of coastal ecosystems, including coral reefs, are expected along the Mexican Caribbean and numerous key points of Cuba and other Caribbean countries.

Exploring New Frontiers in Marine Radioisotope Tracing – Adapting to New Opportunities and Challenges

Radioisotopes have been used in earth and environmental sciences for over 150 years and provide unique tools to study environmental processes in great detail from a cellular level through to an oceanic basin scale. These nuclear techniques have been employed to understand coastal and marine ecosystems via laboratory and field studies to understand how aquatic organisms respond to environmental stressors including temperature, pH, nutrients, metals, organic anthropogenic compounds and biological toxins. Global marine issues, such as ocean warming, deoxygenation, plastic pollution, ocean acidification, increased duration and intensity of toxic harmful algal blooms (HABs), and coastal contamination are all impacting marine environments, thereby imposing various environmental and economic risks. Being able to reliably assess the health of coastal and marine ecosystems, and how they may respond to future disturbances, can provide vital information for society in the sustainable management of their marine environments. This paper summarises the historical use of radiotracers in these systems, describes how existing techniques of radioecological tracing can be developed for specific current environmental issues and provides information on emerging issues that would benefit from current and new radiotracer methods. Current challenges with using radioecological tracers and opportunities are highlighted as well as opportunities to maximise the uptake of these methods to greatly increase the ability of environmental managers to conduct evidence-based management of coastal and marine ecosystems.

The Economics of the Joint Management of Water Resources and Aquatic Species in the United States

AbstractThe health of many marine, coastal, freshwater, and other aquatic ecosystems is inextricably linked to decisions about the management of water quality and quantity. In this article we revie...

Opportunities and challenges in incorporating benthic foraminifera in marine and coastal environmental biomonitoring of soft sediments: from science to regulation and practice

Scientific studies have demonstrated the usefulness of benthic foraminifera as bioindicators to assess the health of marine, coastal, and transitional ecosystems. Similar to macrofauna, these organisms are reliable proxies for biomonitoring. Despite recent scientific advances, Brazilian official monitoring plans using biotic indices on coastal and ocean environments with soft sediment areas remain mostly restricted to a few types of organisms. Therefore, to include benthic foraminifera in Brazilian biomonitoring routines regulated by national environmental guidelines and standards, the paper presents the challenges, which must be overcome, some recommendations and steps to move forward to implement foraminifera as bioindicators in biomonitoring routines. In light of it, it is essential to consider the contribution of the Brazilian foraminiferal research in this implementation process, improving ecological quality indices, adapting methods, and applying genetics tools. This paper is a step in this direction, which aims to strengthen the role of benthic foraminifera as a reliable tool in Brazilian biomonitoring.

Not so sluggish: movement and sediment turnover of the world’s heaviest holothuroid, Thelenota anax

Ecology of many sea cucumbers, including the world’s heaviest holothuroid Thelenota anax, remains understudied, hindering effective fisheries management and conservation. We located, measured and weighed 38 T. anax over 10 days at Lizard Island, northeast Australia. Body length alone was a suitable predictor of body weight for this species. Short-term (1–4 h) rates of displacement and sediment defecation were measured on 30 animals across three sites. The animals were highly mobile, moving, on average, 57 cm h−1 (± 11 SE), and reworking 34 g dry weight of sediment h−1 (± 7 SE). The animals moved more and defecated more sediments in areas where surrounding sediments had lower levels of organic matter. Defecation rates increased through daytime hours. The high mobility of T. anax should confer an advantage for mate-finding but also could increase spillover from small marine reserves into fishing grounds. Our findings galvanise a pattern of high mobility in larger holothuroids and show that food resources and time of day modulate the extent of sediment reworking by deposit feeding holothuroids. The high sediment turnover rate highlights the detrimental effect that overfishing of these large holothuroids will have on the health of coastal marine ecosystems.