An Overview of Coastal Environmental Health Indicators

Discussions of the coastal environment and its health can be improved by more precise use of terms and clarification of the relationship, if any, between the health of ecosystems and the risks to human health. Ecosystem health is seldom defined and, in any case, has to be regarded in different terms than human health. Ecosystem health should embody both the structure and function of the ecosystem. One attractive concept is to define the health of ecosystems in terms of their vigor, organization and resilience. From that perspective, the health of an ecosystem is reduced if it becomes a less vigorous producer of valuable living resources, less diverse and organized, and more susceptible to and slower to recover from stress. Useful indicators of ecosystem health should reflect these properties, but also be supported by understanding of cause and effect relationships generated through research. Significant challenges remain in the integration of indicators in terms of both their interrelationships and holistic significance. There is also a need to develop indicators that are relevant to emerging threats to coastal ecosystems.     

上海海岸带及邻近岛屿植物分布特点和环境因子分析

上海海岸带及邻近岛屿发育至今,生物、非生物环境因子起着重要作用。其中,成岛年龄、高程、土壤种类、土壤养分、土壤含盐量、土壤pH值等影响着诸岛植物群落的形成、定居与演替。在多年野外调查基础上,本文以时空跨度,运用PC-ORD生态学多变量分析软件中的典范对应分析（CCA）二维排序方法,阐述了上海海岸带及邻近岛屿植物群落的植物多样性,报导了上海海域诸岛的植物种类,并对该区域多种生境下植物群落的演替现状和所适应的环境因子进行了分析,为研究分析上海海岸带及邻近岛屿植被及其整个生态系统提供了基础资料。     

Streamflow-induced variations in nitrate flux in tributaries to the Atlantic Coastal Zone

Streamflow-related variability in nutrient flux represents an important source of uncertainty in managing nutrient inputs to coastal ecosystems. Quantification of flux variability is of particular interest to coastal resource managers in adopting effective nutrient-reduction goals and monitoring progress towards these goals. We used historical records of streamflow and water-quality measurements for 104 river monitoring stations in an analysis of variability in annual and seasonal flux of nitrate to the Atlantic coastal zone. We present two measures of temporal flux variability: the coefficient of variation (CV) and the exceedence probability (EP) of 1.5 times the median flux. The magnitude of flux variations spans a very wide range and depends importantly upon the season of year and the climatic and land-use characteristics of the tributary watersheds. Year-to-year variations (CV) in annual mean flux range over two orders of magnitude, from 3–200% of the long-term mean flux, although variations more typically range from 20–40% of the long-term mean. The annual probability of exceeding the long-term median flux by more than 50% (EP) is less than 0.10 in most rivers, but is between 0.10 and 0.35 in 40% of the rivers. Year-to-year variability in seasonal mean flux commonly exceeds that in annual flux by a factor of 1.5 to 4. In western Gulf of Mexico coastal rivers, the year-to-year variablity in the seasonal mean flux is larger than in other regions, and is of a similar magnitude in all seasons. By contrast, in Atlantic coastal rivers, the winter and spring seasons, which account for about 70% of the annual flux, display the smallest relative variability in seasonal mean flux. We quantify the elasticity of nutrient flux to hypothetical changes in Streamflow (i.e., the percent increase in flux per percentage increase in mean discharge) to allow the approximation of flux variability from streamflow records and the estimation of the effects of future climatically-induced changes in Streamflow on nutrient flux. Flux elasticities are less than unity (median = 0.93%) at most stations, but vary widely from 0.05% to 1.59%. Elasticities above unity occur most frequently in the largest rivers and in rivers draining the arid portions of the western Gulf of Mexico Basin. Historical flux variability and elasticity generally increase with the extent of arid conditions and the quantity of nonurban land use in the watershed. We extend the analysis of flux variability to examine several case studies of highly unusual meteorological events capable of significantly elevating nitrate flux and degrading estuarine ecology.     

Fungi Inhabiting the Coastal Zone of Lake Magadi

Fungi able to survive under the extreme environment of soda lakes remain poorly studied. This paper presents data on the diversity and ecophysiology of filamentous fungi inhabiting one of the most alkaline habitats of the Earth: Lake Magadi, where pH values may exceed 11–12. The lake is home to a large number of prokaryotes, which form complex communities with algae and some other eukaryotes. In this study, 22 species of filamentous fungi isolated from soil samples collected on the coastline of Lake Magadi have been characterized using a systematic approach, which includes selective isolation, an analysis of morphological traits, molecular–genetic analysis, growth experiments to determine pH and temperature preferences, and an analysis of the dependence on NaCl concentrations. According to the results, alkaline soil from the Lake Magadi coastline is colonized by fungi with differing types of adaptation to high pH values. Alkaliphilic and alkalitolerant fungi belong to different families of Ascomycetes, mainly to Plectosphaerellaceae, as well as to Onygenaceae, Trihocomaceae, and Pleosporaceae. Sodiomyces tronii and S. magadii are new obligate alkaliphilic species within the earlier monotypic genus Sodiomyces (Plectosphaerellaceae). According to the growth experiments, obligate alkaliphilic isolates demonstrate thermo- and halotolerant properties. The problems of adaptation to the external pH, possible substrate preferences, and association of alkaliphilic fungi with other organisms are discussed.     

Linking Molecular Microbial Ecology to Geochemistry in a Coastal Hypoxic Zone

Multiple environmental mechanisms have been proposed to control bottom water hypoxia (<2 mg O₂ L^?1) in the northern Gulf of Mexico Louisiana shelf. Near-bottom hypoxia has been attributed to a direct consumption of oxygen through benthic microbial respiration and a secondary chemical reaction between oxygen and reduced metabolites (i.e. ferrous iron and total sulfide) from these populations. No studies to date have examined the metabolically active microbial community structure in conjunction with the geochemical profile in these sediments. Temporal and spatial differences in dissolved and solid phase geochemistry were investigated in the upper 20 cm of the sediment column. Pyrosequencing of reverse transcribed small subunit (SSU) ribosomal ribonucleic acid (rRNA) was used to determine population distribution. Results indicated that populations shallower than 10 cm below surface were temporally variable yet uniform between sites, while below this depth, populations were more site-specific. This suggests a potential interaction between the water column and the benthic microbial population limited to a shallow depth. The presence of dissolved reduced iron in the upper sediment column was indicative of low oxygen concentration, yet sulfide was at or below detection limits. Putative sulfate and iron reducing and oxidizing populations were metabolically active at similar depths suggesting potential recycling of products. Results from this study indicate low carbon concentrations in the shallow sediments limit general metabolic activity, reducing the potential for microbial respiration. Supplemental materials are available for this article. Go to the publisher's online edition of Geomicrobiology Journal to view the supplemental file.     

Characterization of Coastal Urban Watershed Bacterial Communities Leads to Alternative Community-Based Indicators

Background

Microbial communities in aquatic environments are spatially and temporally dynamic due to environmental fluctuations and varied external input sources. A large percentage of the urban watersheds in the United States are affected by fecal pollution, including human pathogens, thus warranting comprehensive monitoring.

Methodology/Principal Findings

Using a high-density microarray (PhyloChip), we examined water column bacterial community DNA extracted from two connecting urban watersheds, elucidating variable and stable bacterial subpopulations over a 3-day period and community composition profiles that were distinct to fecal and non-fecal sources. Two approaches were used for indication of fecal influence. The first approach utilized similarity of 503 operational taxonomic units (OTUs) common to all fecal samples analyzed in this study with the watershed samples as an index of fecal pollution. A majority of the 503 OTUs were found in the phyla Firmicutes, Proteobacteria, Bacteroidetes, and Actinobacteria. The second approach incorporated relative richness of 4 bacterial classes (Bacilli, Bacteroidetes, Clostridia and α-proteobacteria) found to have the highest variance in fecal and non-fecal samples. The ratio of these 4 classes (BBC∶A) from the watershed samples demonstrated a trend where bacterial communities from gut and sewage sources had higher ratios than from sources not impacted by fecal material. This trend was also observed in the 124 bacterial communities from previously published and unpublished sequencing or PhyloChip- analyzed studies.

Conclusions/Significance

This study provided a detailed characterization of bacterial community variability during dry weather across a 3-day period in two urban watersheds. The comparative analysis of watershed community composition resulted in alternative community-based indicators that could be useful for assessing ecosystem health.     

On the Potential Contribution of Microfungi to the Decomposition of Reed Leaf Detritus in a Coastal Lagoon: A Laboratory and Field Experiment

The potential contribution of microfungi to reed decomposition in a coastal habitat (Le Cesine Lagoon, Italy) was investigated under laboratory and field conditions. Leaf pack mass and surface loss, ergosterol content and O₂ uptake were used to construct carbon budgets and an empirical ergosterol‐to‐O₂ uptake relationship based on literature data was used to estimate the contribution of microfungi. Under laboratory conditions, reed carbon loss was entirely due to leaching and microbial respiration. In contrast, C losses observed in the field were accounted for by microbial respiration and macroinvertebrate shredding almost equally. Microfungi were estimated to account for 98% and 69% of microbially‐respired carbon under laboratory and field conditions, respectively. Our results provide a preliminary, quantitative assessment of microfungal contribution to reed decomposition in brackish habitats. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

The Ability and Right of Coastal States to Monitor Ship Movement: A Note

Using the Global Positioning System (GPS), a ship knows its position continuously to within a few meters anywhere in the ocean. Small, lightweight, relatively inexpensive instruments calculate the ship's position from signals of passing GPS satellites. Oceanographers now attach GPS receivers to floating instruments. These floating buoys broadcast their positions and other data to passing communication satellites, which in turn transmit that information to shore stations. Clearly, a similar locator device (LD) could be placed aboard a ship and its position tracked continuously from shore. We suggest that under the U.N. Law of the Sea Treaty, coastal states can require activated LDs on all ships, including war ships, traversing its territorial sea, archipelagic sea lanes, and straits used for international passage. We further suggest states can require many classes of ships to carry activated LDs while traversing their exclusive economic zones or working above their continental shelf.     

广州市海岸带生态环境现状及保护

广州市海岸带位于珠江入海口,为淤泥质冲积平原,滩涂面积广阔,湿地类型多样,野生动植物资源丰富.调查分析显示,近20年以来,海岸带的生态环境发生了深刻的变化.突出表现为天然湿地丧失或转化为受控湿地、淡水水体和海水水质恶化、生物资源衰退、外来生物入侵、洪涝灾害加剧等问题,形成人为活动干扰十分强烈的生态脆弱带.这些问题的产生与海涂围垦等海岸带开发活动密切相关.随着广州市“南拓”空间发展战略的提出,海岸带资源开发力度将进一步加强,尽管市政府在海洋保护、红树林湿地恢复重建和保护区建设等方面开展了大量工作,但海岸带的生态环境保护依然不容忽视.     

Response of Phytoplankton Photophysiology to Varying Environmental Conditions in the Sub-Antarctic and Polar Frontal Zone

Climate-driven changes are expected to alter the hydrography of the Sub-Antarctic Zone (SAZ) and Polar Frontal Zone (PFZ) south of Australia, in which distinct regional environments are believed to be responsible for the differences in phytoplankton biomass in these regions. Here, we report how the dynamic influences of light, iron and temperature, which are responsible for the photophysiological differences between phytoplankton in the SAZ and PFZ, contribute to the biomass differences in these regions. High effective photochemical efficiency of photosystem II (/ 0.4), maximum photosynthesis rate (), light-saturation intensity (), maximum rate of photosynthetic electron transport (1/), and low photoprotective pigment concentrations observed in the SAZ correspond to high chlorophyll and iron concentrations. In contrast, phytoplankton in the PFZ exhibits low / ( 0.2) and high concentrations of photoprotective pigments under low light environment. Strong negative relationships between iron, temperature, and photoprotective pigments demonstrate that cells were producing more photoprotective pigments under low temperature and iron conditions, and are responsible for the low biomass and low productivity measured in the PFZ. As warming and enhanced iron input is expected in this region, this could probably increase phytoplankton photosynthesis in this region. However, complex interactions between the biogeochemical processes (e.g. stratification caused by warming could prevent mixing of nutrients), which control phytoplankton biomass and productivity, remain uncertain.     

Evaluation of Potential Indicators of Viral Contamination in Shellfish and Their Applicability to Diverse Geographical Areas

The distribution of the concentration of potential indicators of fecal viral pollution in shellfish was analyzed under diverse conditions over 18 months in diverse geographical areas. These microorganisms have been evaluated in relation to contamination by human viral pathogens detected in parallel in the analyzed shellfish samples. Thus, significant shellfish-growing areas from diverse countries in the north and south of Europe (Greece, Spain, Sweden, and the United Kingdom) were defined and studied by analyzing different physicochemical parameters in the water and the levels of Escherichia coli, F-specific RNA bacteriophages, and phages infecting Bacteroides fragilis strain RYC2056 in the shellfish produced, before and after depuration treatments. A total of 475 shellfish samples were studied, and the results were statistically analyzed. According to statistical analysis, the presence of human viruses seems to be related to the presence of all potential indicators in the heavily contaminated areas, where E. coli would probably be suitable as a fecal indicator. The F-RNA phages, which are present in higher numbers in Northern Europe, seem to be significantly related to the presence of viral contamination in shellfish, with a very weak predictive value for hepatitis A virus, human adenovirus, and enterovirus and a stronger one for Norwalk-like virus. However, it is important to note that shellfish produced in A or clean B areas can sporadically contain human viruses even in the absence of E. coli or F-RNA phages. The data presented here will be useful in defining microbiological parameters for improving the sanitary control of shellfish consumed raw or barely cooked.     

广西北部湾海岸带、海岛的外来入侵植物

为保护广西北部湾海岸带、海岛的植物多样性和生态系统多样性,通过样方、样带法野外实地调查并结合文献资料,对其外来入侵植物的物种组成、原产地、生活型、入侵途径和危害状况等进行了分析。结果表明,广西北部湾海岸带、海岛共有入侵植物64种,隶属28科55属,其中菊科(Asteraceae)最多(15种)。草本植物最多,有48种(75.00%)。原产地来自美洲的植物最多,有49种。入侵风险等级可划分为5个等级,其中Ⅰ级严重危害的有8种(12.50%)。与广西、广东、海南及华南地区的外来入侵植物在物种组成、生活型和原产地等方面呈现出较强的相似性;北部湾与广西中越边境内陆地区来自美洲的入侵植物都超过60%。因此推测广西外来入侵植物有两条可能的入侵线路：一是从海南登录,二是从中越边境跨入。广西北部湾海岸带、海岛的外来入侵植物总数(相对整个广西)虽较少,但其8种Ⅰ级严重危害植物的防治,仍需引起重视。     

Potential Significance of Lysogeny to Bacteriophage Production and Bacterial Mortality in Coastal Waters of the Gulf of Mexico

The potential effect that induction of lysogenic bacteria has on bacteriophage production and bacterial mortality in coastal waters was investigated, and we present estimates for the percentage of lysogenic cells in a natural aquatic bacterial community. Various concentrations of mitomycin C and exposure times to UV C radiation (UV-C) (wavelength of 254 nm) were used to induce the lytic cycle in lysogenic cells of natural communities of marine bacteria. UV-C treatment occasionally resulted in phage production, but phage production induced by UV-C was always less than that caused by the addition of mitomycin C. There was no evidence that high growth rates of bacteria resulted in lysogenic phage production. The burst size of cells induced by mitomycin C was determined by transmission electron microscopy and ranged from 11 to 45. Dividing the induced phage production by the burst size provided an estimate of the number of lysogenic bacterial cells, which ranged from 0.07 to 4.4% (average, 1.5%) of the total bacterial population. The percentages of lysogenic bacteria that were induced by mitomycin C were similar for samples collected nearshore from the pier of the Marine Science Institute (chlorophyll a, 1.6 to 2.9 (mu)g liter(sup-1)) and in relatively oligotrophic water (chlorophyll a, 0.2 to 0.9 (mu)g liter(sup-1)) collected 25 to 100 km offshore. By using a steady-state model, if all lysogenic bacteria were induced simultaneously, 0.14 to 8.8% (average, 3.0%) of the total bacterial mortality would result from induction of lysogenic cells. If mitomycin C induces all or the majority of lysogenized cells, our results imply that lysogenic phage production is generally not an important source of phage production or bacterial mortality in the coastal waters of the western Gulf of Mexico.     

Consideration of Geography and Wetland Geomorphic Type in the Development of Great Lakes Coastal Wetland Bird Indicators

We examined how geographic distribution of birds and their affinities to three geomorphic wetland types would affect the scale at which we developed indicators based on breeding bird communities for Great Lakes coastal wetlands. We completed 385 breeding bird surveys on 222 wetlands in the US portion of the basin in 2002 and 2003. Analyses showed that wetlands within two ecoprovinces (Laurentian Mixed Forest and Eastern Broadleaf Forest) had different bird communities. Bird communities were also significantly different among five lakes (Superior, Michigan, Huron, Erie, and Ontario) and among three wetland types (lacustrine, riverine, barrier-protected). Indicator values illustrated bird species with high affinities for each group (ecoprovince, lake, wetland type). Species with restricted geographic ranges, such as Alder and Willow Flycatchers (Empidonax alnorum and E. traillii), had significant affinities for ecoprovince. Ten bird species had significant affinities for lacustrine wetlands. Analyses on avian guild metrics showed that Lake Ontario wetlands had fewer long-distant migrants and warblers than other lakes. Numbers of short-distant migrants and total individuals in wetlands were higher in the Eastern Broadleaf Forest ecoprovince. Number of flycatchers and wetland obligate birds were not different among provinces, lakes, or wetland type. One potential indicator for wetland condition in Great Lakes wetlands, proportion of obligate wetland birds, responded negatively to proportion of developed land within 1 km of the wetland. We conclude that, although a guild approach to indicator development ameliorates species-specific geographic differences in distribution, individual species responses to disturbance scale will need to be considered in future indicator development with this approach.     

山东沿海地区海水入侵防治

山东沿海地区海水入侵防治杨明华,文力（中国科学院生态环境研究中心北京１０００８５）ＰｒｅｖｅｎｔｉｏｎｏｆＳａｌｉｎｅＷａｔｅｒＩｕｔｒｕｓｉＯｎｉｎｔｏｔｈｅＣｏａｓｔａｌＺｏｎｅｏｆＳｈａｎｄｏｎｇＰｒｏｖｉｎｃｅ．￥ＹａｎｇＭｉｎｇｈｕａ;Ｗｅ...