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Increasing attention is being paid to estuarine benthic community conservation and restoration globally. In this study, a GIS-based habitat suitability index (HSI) model was utilized to estimate Perinereis aibuhitensis (Grube, 1878) carrying capacity in estuarine wetlands of the Zhimai River, eastern China. Eight parameters were investigated, including sand content, salinity, pH, and petroleum hydrocarbon. Each parameter was investigated by a non-linear suitability function for transition from transformed parameter values into a normalized quality index. The weight of each parameter factor was determined by an analytic hierarchy process. A functional relationship was established between habitat suitability and population abundance to assess the carrying capacity. Twelve observation stations, divided into central, eastern, and western regions, were selected to collect data on biogeochemical and environmental parameters. These data were interpolated by GIS. The HSI model was then applied to obtain thematic maps of suitable habitat areas for P. aibuhitensis and corresponding carrying capacities. Results showed that central and western regions (approximately 1.013 km2, accounting for 66.38% of the total area) had a relatively high carrying capacity (130-150 ind. m-2), whereas the carrying capacity of the eastern region was below average. The abundance of P. aibuhitensis did not reach the carrying capacity of the environment under present conditions, especially in the eastern region. Results of the present study indicate that the execution of P. aibuhitensis restoration is feasible in this region; the areas around Stn 7 and in the eastern region are recommended for restoration.

Bacterial and archaeal communities play important roles in wetland ecosystems. Although the microbial communities in the soils and sediments of wetlands have been studied extensively, the comprehensive distributions of planktonic bacterial and archaeal communities and their responses to environmental variables in wetlands remain poorly understood. The present study investigated the spatiotemporal characteristics of the bacterial and archaeal communities in the water of an artificially irrigated estuarine wetland of the Liaohe River, China, explored whether the wetland effluent changed the bacterial and archaeal communities in the Liaohe River, and evaluated the driving environmental factors. Within the study, 16S rRNA quantitative PCR methods and MiSeq high-throughput sequencing were used. The bacterial and archaeal 16S rRNA gene abundances showed significant temporal variation. Meanwhile, the bacterial and archaeal structures showed temporal but not spatial variation in the wetland and did not change in the Liaohe River after wetland drainage. Moreover, the bacterial communities tended to have higher diversity in the wetland water in summer and in the scarce zone, while a relatively higher diversity of archaeal communities was found in autumn and in the intensive zone. DO, pH and PO4-P were proven to be the essential environmental parameters shaping the planktonic bacterial and archaeal community structures in the Liaohe River estuarine wetland (LEW). The LEW had a high potential for methanogenesis, which could be reflected by the composition of the microbial communities.

Reed marshes are vital habitats for many species of birds, some of which are wholly or largely dependent on this habitat. Reed harvesting in winter is a common practice for increasing economic benefits, but it also promotes reed growth and maintains reed marsh landscapes by removing dry reed stalks. Different reed cutting intervals create different habitat conditions and thus lead to differences in habitat use by marsh birds. Although many studies have reported birds and their habitat conditions in reed marshes with different cutting schemes in Europe, few studies have been conducted in Asia, where reed marshes are widely distributed. Here, we conducted a one-year survey (from March 2019 to February 2020) on birds and their habitat conditions (vegetation and food) in reed marshes with three cutting intervals: age 1 (cutting every year), age 2 (cutting with one-year interval), and uncut (uncut for four years), at Chongming Dongtan, an estuarine wetland on China’s coast. As the cutting interval increased, the growing reed density decreased, the dry reed and total reed density increased, and the food density (in terms of reed seeds, arthropods, and arthropod eggs) decreased. A total of 4627 birds of 23 species were captured by mist nets. In general, species capture rates were similar among the three habitats in the same season, and individual capture rates in uncut reed marshes were lower than those in age 1 and age 2 marshes. This was probably because the relatively low density of reed stems promoted the movement of birds to age 1 and age 2 marshes, where birds could find abundant food. In contrast to previous studies, we found that age 1 marshes provide suitable habitats for birds soon after vegetation is restored in summer. However, reed parrotbills (Paradoxornis heudei), a common reed marsh specialist, had high capture rates in uncut reed marshes in winter. This is probably because they live in dense vegetation, and dense vegetation can reduce threats from aerial predators. This study emphasizes that habitat use should be considered in reed cutting practices and that a mixture of reed marshes with different cutting intervals benefits different birds and also different requirements of the same birds over the course of the year.

There is a need for a consolidated source of information on native vegetation seed collection and germination strategies in southern California. Published literature on these methods is often experimental, species-specific, and widely scattered throughout online and print media. Planting and restoration strategies may need to be site-specific; however, similar methodological approaches are often utilized allowing for the development of general strategies for seed collection, storage, and germination methods. A better understanding of species-specific seed attributes and growth processes will help restoration ecologists collect high-quality, viable seed, thereby increasing the potential success of the restored vegetation community by reducing plant mortality, project costs, and effort. This paper synthesizes seed collection and germination strategies for native vegetation common to southern California estuarine wetland, coastal dune, and coastal sage scrub systems.

Coastal wetlands are considered to be amongst the most productive ecosystems and can provide invaluable ecological services. However, coastal wetlands are listed amongst the most threatened ecosystems suffering from anthropogenic activities. The loss or degradation of coastal wetlands has drawn a high level of attention to wetland restoration. Improvement of the structure and function of degraded, damaged and destroyed wetlands may be achieved through ecological restoration. Large numbers of restoration projects have been conducted worldwide based on different restoration goals and different methods. It is undoubtedly important to evaluate whether coastal wetland restoration is successful. However, coastal wetland restoration assessment has become challenging because of current disagreement on definitions and concepts of restoration evaluation. We reviewed the methodology of coastal wetland restoration and criteria for success evaluation, and then summarized the issues for current wetland restoration and success evaluation based on literature review. Moreover, we used an estuarine wetland affected by urbanization as a sample to demonstrate how to establish a success indicator system for guiding wetland restoration and evaluating the success of wetland restoration.

Estuarine wetland degradation of Liao River caused by human activities has gradually caught people’s attention. It has left great influence on structure, quality and functions of natural ecological system. This thesis took Panjin area as the research object and applied remote sensing and GIS technology to analyze structure, quality, functions and impact factors of the ecological system in Panjin area. The results show climate warming is an important reason for the influence that causes changes in wetland ecological system of Panjin area. To a certain degree, development of economy, agriculture, and industry has also impacted the changes in structure, quality, and functions of ecological system in Panjin area. Moreover, nature and human factors have played non-ignorable roles in ecological effect and anthropogenic factor has more obvious effect.

Forty one soil samples were collected from Liaohe estuarine wetland in May 2009 for assessing the distribution, ecological risk, and health risk of dioxin-like PCBs (dl-PCBs). The total concentrations of 12 dl-PCBs ranged from 0.36–1.36 ng/g, with a mean value of 0.77 ng/g. The dominant dl-PCBs were Tetra-CBs, which contributed to 43.9% of the total. The ecological risk of dl-PCBs was analyzed based on the toxic equivalent (TEQ) approach. In this study, the TEQ concentrations of dl-PCBs in soils varied from 0.06–22.55 pg/g, with a mean value of 8.18 pg/g. Human health risk was evaluated based on the non carcinogenic and carcinogenic risk method. Non carcinogenic risk was measured using a hazard quotient (HQ) values for 95% upper control limit (UCL) and maximum concentrations of dl-PCBs. HQ values were lower than 1 under both exposure scenarios, which indicated that the non carcinogenic risk of dl-PCBs was negligible. Carcinogenic risk was estimated based on the criteria of ingestion, dermal contact and in...

This study is a first approach to modelling of fleur de sel production, aimed at increasing its efficiency and contributing to the scarce literature on the topic. Quantitative forecasting of daily production of fleur de sel was applied to an artisanal solar pond unit in the environmentally protected area of Castro Marim, SE Portugal. The numerical model was based on simulations of the evaporation process, taking into account the effect of reduced vapour pressure of the brine solution. The controlling variables chosen as input parameters to the forecast model were brine temperature, brine concentration, harvesting efficiency, albedo, incoming solar radiation, precipitation, air relative humidity, air temperature, atmospheric pressure, day of the year, wind direction, and wind speed. Production predicted by the model was tested against actual production in two crystallisers in the years 2015 and 2017. The statistically evaluated match between the estimated and actual production was highly significant with a mean R-2 of 0.8 and overall error of estimation was 14.5%. The chemical composition of nine samples of fleur de sel was analysed, showing the temporal evolution of several components during the harvesting period. A decrease of NaCl content from 96% to 87% and an increase by one order of magnitude of Mg, S, K, Br, and As were observed. The range of Ca, Si, Al, and Sr contents was 0.12-0.65%, 0.1-0.85%, 0.08- 0.3%, and 0.009-0.013%, respectively. Ba, Fe, Mn, Mo, Pb, and Sn contents had the following ranges: 0.051-0.145, 1.2-5.5, 0.44-1.66, 0.03-0.05

Klemas, V., 2013. Using remote sensing to select and monitor wetland restoration sites: an overview. Coastal and estuarine wetlands represent highly productive and critical habitats for a wide variety of plants and animals and provide protection from storms and wave damage. However, wetland acreage in the continental United States has been steadily decreasing mainly as a result of human activities and sea level rise. Major efforts are being made by federal, state, and local agencies to protect existing wetlands, restore lost wetlands, and improve those stressed by human activities. The restoration process can involve removing exotic plants, removing bulkheads and fill, elevation grading, creating flushing channels, and planting native vegetation. Having developed criteria for selecting wetland sites to be restored or enhanced, wetland managers must prioritize the sites based on ecological and economic considerations. Remote sensing techniques can provide a cost-effective means for selecting resto...

The aims of this research were to:(1) provide a theoretical basis for in-depth analysis of the influence of human activities on estuarine wetlands over a regional scale;(2) quantify the impact of anthropogenic interference on the landscape pattern index;and(3) establish a theoretical basis for the monitoring and evaluation of anthropogenic interference in estuarine wetlands.Based on aerial photographs from 1958,1970,and 1984(2 m resolution),and the spot5 image of 2008(5 m resolution),this study explored the spatiotemporal dynamics of hemeroby and the landscape pattern response scheme through hemeroby analysis,landscape pattern analysis,spatial patch analysis,and GIS spatial analysis in the Dayang estuary.The research evaluates: 1) the primary forcing landscape factors for spatial and temporal variation of hemeroby in an estuarine wetland;2) the response mechanism of landscape pattern index on the type of hemeroby;and 3) landscape indices associated with hemeroby in space.Results indicate that: 1) completely hemeroby regions increased from 4.16 km2 in 1958 to 9.16 km2 in 2008,while partially hemeroby regions increased from 115.82 km2 to 180.57 km2,and hemeroby regions declined from 291.23 km2 to 221.13 km2.Historically,hemeroby showed heterogeneous changes.The center of hemeroby moved gradually from land to ocean,and ocean aquaculture is the main driving factor in the change of hemeroby.Over time,hemeroby shows an upward trend,but the intensity of hemeroby changes are different at different historical periods,and hemeroby shows non-homogeneous characteristics at different historical periods.Comparing the change in different landscape types,we found paddy yield was the primary landscape type in 1958,aquaculture water in ocean and farmland showed upward increases in 1970,and after the 1980s aquaculture water in the ocean was the primary landscape type of human activities.Temporally,anthropogenic disturbance has led to an overall decrease in the number of patches(NP),edge density(ED),mean shape index(MSI),and area-weighted mean patch fractal dimension(AWMPFD) between 1958 and 2008.Through analysis of the landscape pattern index of different hemeroby types,we found that human disturbance has a certain effect on the landscape pattern index.Spatially,hemeroby is positively correlated with number of patches(NP),edge density(ED),and area-weighted mean patch fractal dimension(AWMPFD) in order of decreasing influence,while it is not significantly correlated with the mean shape index(MSI).The relationship between human disturbance activities and landscape pattern(four indices: number of patches(NP),edge density(ED),area-weighted mean patch fractal dimension(AWMPFD),mean shape index(MSI)) constituted differences in time and space within estuarine areas.Thus,heterogeneity and complexity of the landscape were greater in human disturbance areas over some time intervals,and heterogeneity and complexity of landscape showed declines in the continuing role of human disturbance with time.Therefore,the dimension of time and space should be distinguished in remote sensing monitoring responses of landscape patterns on human activities in estuarine wetlands.

The diverse mixture of contaminants frequently present in estuaries complicates their assessment by routine chemical or biological analyses. We investigated the use of gene expression to assess contaminant exposure and the condition of southern California estuarine fish. Liver gene expression, plasma estradiol concentrations, and gonad histopathology were used to study biological condition in longjaw mudsuckers (Gillichthys mirabilis). Metals, legacy organochlorine pesticides, PCBs, and contaminants of emerging concern were detected in sediments and whole fish. Overall gene expression patterns were characteristic to each of four sites investigated in this study. Differentially expressed genes belonged to several functional categories including xenobiotic metabolism, detoxification, disease, and stress responses. In general, plasma estradiol concentrations were similar among fish from all areas. Some fish gonads had pathologic changes (e.g., infection, inflammation) that could indicate weakened immune systems and chronic stress. The differential expression of some genes involved in stress responses correlated with the prevalence of histologic gonad lesions. This study indicates that gene expression is a promising tool for assessing the biological condition of fish exposed to environmental contaminants.

Kandelia candel, Aegiceras corniculatum and Avicennia marina are the dominant plant species of Quanzhou Bay Estuarine Wetland. In this study, we had established the four-parametric logistic equations of plant height, tree crown diameter and leaf length versus the time after they were transplanted (sowed). The development pattern of the wetland plants was different among species and locations. The growth parameters estimated using four logistic equations is able to provide detailed plant dynamic growth information for Aegiceras corniculatum, Kandelia candel and Avicennia marina. By comparison, it is difficult to assess the adaptability of Kandelia candel to the environment of the region whether the upstream or downstream. However, we can deduce that Avicennia marina is suitable for growing in the upstream and downstream of Luoyang River, not in the midstream. The results will provide scientific basis for the allocation and arrange on plant species in the wetland.

Spatial and temporal distribution of octylphenol (OP) and nonylphenol (NP) in Mai Po Marshes, a subtropical estuarine wetland in Hong Kong, were investigated. Surface water samples were collected every month from 11 sites during the period of September-December 2004. Concentrations of OP and NP ranged from 11.3 to 348 ng/L and from 29 to 2591 ng/L, respectively. The high levels of NP and OP were found in November and December than in September and October. The levels of OP and NP have no significant spatial differences except September. Total organic matter in the sediments appeared to be an important factor in controlling the fate of these compounds in the aquatic environment.

Shorebirds are declining all around the world, mostly due to deterioration of the estuarine habitats used in winter and migration. Estuaries cover small areas, so it is essential to guarantee that shorebirds can access all the tidal flats where they usually feed at low-tide. Studying use of space by dunlins ( Calidris alpina ) in the Tagus estuary (Portugal), we noted that lack of suitably located high-tide roosts can limit the access of shorebirds to feeding habitats. Density of dunlins on foraging areas declined significantly with distance to the nearest roost, and fewer than 20% individuals foraged more than 5 km from two roosts where they were dye-marked. So to permit full access to feeding areas it is important to maintain a network of suitably located high-tide roosts. We developed a GIS modelling methodology to evaluate the adequacy of existing roost networks, and to estimate the consequences of losing or creating new roosts. The methodology requires maps with the location of roosts and foraging habitats, and knowledge of the distances that birds are willing to fly to reach foraging areas. It quantifies the proportion of foraging areas close to the existing roosts and the average distance that birds have to fly to reach potential feeding sites. Applying this methodology to the Tagus estuary we concluded that lack of roosts probably explains why the intertidal flats in the north-west of the estuary are underused by shorebirds. A modelling exercise suggested that this gap could be eliminated by creating a roost in an old drained wetland area. We also modelled the impact of the loss of two roosts that are currently threatened. Without them almost half of the available feeding areas will be too far from roosts to be efficiently used by dunlins, and possibly by other shorebirds.

Assessing performance of restored and created wetlands for compensatory mitigation and restoration poses a mismatch between long-term processes and the short- term expediency of management decisions. If they were predictable, patterns in the temporal development of important wetland processes could reduce long-term uncertainty of the outcome of restoration projects. To test our ability to predict long-term trends and patterns in the development of a restored wetland based on the first 7 yr of its development, we analyzed 16 ecosystem functional attributes of the Gog-Le-Hi-Te Wetland, in the Puyallup River estuary, Puget Sound, Washington, USA. This estuarine wetland system was restored to tidal inundation in 1986. Only a few of the 16 ecosystem attributes analyzed showed functional trajectories toward equivalency with natural wetlands, and many were incon- clusive or suggested disfunction relative to reference wetlands. Natural variability among reference sites also inhibited our ability to interpret an expected asymptote in developmental trajectories. The ability of wetland managers to assess compensatory-mitigation success over short- term (e.g., regulatory) timeframes depends upon the selection of wetland attributes that can predict long-term trends in the development of the restored/created system. However, we are hampered by a basic lack of long-term data sets describing the patterns, trends, and variability in natural wetland responses to disturbance, as well as natural variability in wetland attributes in presumably mature wetland communities. Ultimately, it may be nec- essary to supplant our descriptive means of assessing functional equivalency with simple, controlled manipulative experiments or assays, standardized across restoration/mitigation and reference sites.

The restoration and creation of freshwater and estuarine wetlands are important practices designed to increase wetland acreage and mitigate for the extensive losses of wetland area all over the world. Wetland restoration, defined as the reestablishment of wetlands where they once existed, and wetland creation, where entirely new wetlands are established in upland locations, require an understanding of hydrology, soils and landscape setting to foster the development of native biotic communities, including vegetation, invertebrates and amphibians. Restoration projects may take decades to fully develop; success may be measured by comparison of key indicators with natural wetlands. Keywords: wetland restoration; wetland creation; aquatic plants; hydric soils; amphibians

Approximately 215 million acres 3 of wetlands existed in the conterminous U.S. at the time of the nation's settlement. By the mid-1970's, 99 million acres remained. The U.S. wetland resource for the ‘lower 48’ states encompassed 93.7 million acres of palustrine wetland of which 49.7 million were forested, and 5.2 million acres of estuarine wetlands of which 0.5 million were either shrubs, scrub trees or forested. Wetlands now cover about 5% of the land surface, and total wetland acreage amounts to an area roughly the size of California. Half of these wetlands are forested. Annual wetland losses averaged 458 000 acres: 440 000 acres of palustrine losses of which 300 000 are forested, and 18 000 acres of estuarine wetland losses of which less than 1000 acres are shrubs, scrub trees or forested. This annual loss equals an area about half the size of Rhode Island. Of these losses, 66% are forested wetlands. Agricultural development was responsible for 87% of wetland losses and 90% of the losses of forested wetlands. Urban development and other development caused only 8% and 5% of the losses, respectively. Forested-wetland losses caused by urban development and other development were 6% and 4%, respectively.

There is a general community perception that as the natural lands of catchments are converted to agricultural, residential and industrial sites, large areas of wetlands have been lost. Although this is probably true in many instances, there is a marked lack of information on which to base this assumption. Not only is there a lack of information about what wetlands have been lost, there is even less information about the impact of the losses on associated communities. Examples of changes to some of the major estuarine wetlands, mangroves and seagrasses in NSW waters will be presented and some of the consequences will be discussed. Rehabilitation of wetland areas is an obvious response to past losses, however on what basis should these often expensive restoration works be undertaken, how feasible is restoration and what should be the outcome of restoration? A number of rehabilitation and pilot projects have been carried out over the last decade and some of the problems they have raised, as well as the results they have achieved, will be summarised.

Urban areas are increasingly occupying the margins of estuarine wetlands. Consequently, it becomes important to understand how the presence of these urban areas influences the use of adjacent intertidal habitats by waterbirds. Wintering waterbirds were regularly counted on 28 mudflat sectors along the northern margin of the river Tagus estuary, Portugal, which includes large urbanized extensions. Sectors were characterized using 16 variables related to its physical characteristics and human influence and related to bird density and diversity using multiple linear regression. Species richness was positively influenced by wider mudflats and a margin covered with saltmarsh. The individual response of seven of the most abundant bird species to these variables differed between species, but the abundance of half of these species was significantly influenced by variables potentially related to the presence of urban areas.

Descriptions of, and keys to the three species of Spartina in New Zealand: S. alterniflora, S. anglica, S. × townsendii, are presented with distribution maps for each. The introduction, history, planting, and spread of each species is discussed as is its ecology, especially in relation to past and future potential for spread. In some places the problems caused by its spread are virtually insurmountable. With renewed appreciation of estuarine wetlands in their natural states, planting of any species of Spartina around the coast of New Zealand should not be allowed to take place. Suitable control and eradication measures need to be developed where Spartina is already present.