Project

Aquatic Habitat Ecology & Conservation: Continental and Marine Ecosystems Connectivity

Goal: https://www.frontiersin.org/research-topics/6705/aquatic-habitat-ecology-conservation-continental-and-marine-ecosystems-connectivity

About this Research Topic

The ‘Aquatic Habitat Conservation in South America’ Symposium occurred during the XXI Brazilian Society of Ichthyology Meeting. The proceedings were published as a special issue in the Journal of Fish Biology (vol. 89, Number 1, June 2016). In this special issue, authors provided an analytical overview of problems faced by the conservation of fishes and aquatic habitats of South America. Habitat loss emerged as the greatest concern for all South American aquatic ecosystems, with a long list of causes related to unsustainable development models.

Based on this finding, we would like to extend this topic to other continents, different climates, fauna and flora around the world. Our goal is to provide a comprehensive and multidisciplinary overview of variables that influence flora and fauna distributions and shape their ecological interactions within aquatic ecosystems.

Thereby, this Research Topic aims to provide a discussion forum to better understand the factors that lead to the loss of aquatic habitats and its effect on aquatic communities and ecosystem functioning, as well as the efforts being made to promote restoration of these ecosystems.

All topics related to aquatic habitat (marine and freshwater) ecology and conservation are therefore welcome. Local studies, as well as national and international efforts, to preserve and restore the functionality of aquatic ecosystems are invited and can be presented in the form of current research methods and findings, review articles, opinion pieces or expanded case studies and pilot programs designed to better understand the best practices of aquatic ecosystems management and restoration.

Keywords: Ecology, Aquatic Conservation, Climate change, habitat loss, microplastics

Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.

Submission deadlines
01/02/2018 Abstracts
01/11/2018 Manuscripts

Updates
0 new
0
Recommendations
0 new
0
Followers
0 new
14
Reads
0 new
74

Project log

Mário Barletta
added a research item
Plastic particle occurrence in the digestive tracts of fishes from a tropical estuarine system in the Gulf of Cali-fornia was investigated. A total of 1095 fish were analysed, representing 15 species. In total 1384 particles of plastic debris were recovered from the gastrointestinal tracts of 552 specimens belonging to 13 species, and all consisted of threads, the majority of which were small microplastics (0.23 to 1.89), followed by large micro-plastics (2.07 to 4.49), and few mesoplastics (5.4 to 19.86). Plastic particles were identified using ATR-FTIR spectroscopy. The mean frequency of occurrence of plastics in the gastrointestinal tracts of fishes from this system was 50.5%, which is higher than frequencies reported in similar systems in other areas. The polymers identified by ATR-FTIR were polyamide (51.2%), polyethylene (36.6%), polypropylene (7.3%), and polyacrylic (4.9%). These results show the first evidence of plastic contamination for estuarine biota in the Gulf of California.
Mário Barletta
added a research item
Microplastics (MPs) are present in high densities in estuaries, where they become easily available to the biota. The aim of this study was to describe a methodology developed to study the relationship among the spatio-temporal patterns of habitat utilization, feeding ecology and MPs contamination across the different ontogenetic phases of fishes belonging to different trophic levels and living along the riverine-estuarine-coastal food chain (ecocline) of a tropical environment case study (Goiana Estuary). The water column of Goiana Estuary was examined for the seasonal and spatial variation of MPs (< 5 mm) and their quantification relative to zooplankton and demersal fish species contamination following the same sampling design. The fish species were assigned to different size classes (juvenile, sub-adult and adult). A total mean of 13.7x10 3 /m 3 (Zooplankton: 99%, Ichthyoplankton: 0.6%, microplastics: 0.2%) were captured in the seston. The highest amounts of MPs were observed during the late rainy season. The density of MPs in the water column determines their bioavailability to plankton feeders, and then to larger predators. This process possibly promotes the transfer of MPs between trophic levels. Polyamide (Nylon) and polyethylene blue fibres were the most frequent types of MPs found in the estuary. Their presence could possibly be linked to nets and cables used in fisheries and other maritime operations. Juveniles of socioeconomically important species (Cynoscion acoupa-Acoupa weakfish and Centropomus undecimalis-Snooks) occur in the upper estuary, an important nursery ground during the early rainy season. Sub-adults also inhabit the upper estuary, a rich feeding ground, where marine predators are absent and competition is reduced. When river runoff increases, Acoupa weakfish and Snooks move to adjacent coastal areas. During this time of the year, species of these genera spawn close to the entrance of the estuarine ecosystem. During the end of the dry season, the juveniles of C. acoupa and C. undecimalis use the upper and middle estuary as nursery. Studies on MPs distribution in relation to spatial and temporal variation of the fauna and environmental factors, which influence the movements of the marine biota, are increasing in quantity and quality. If these sampling strategies are replicated in other estuaries, comparisons could be made. Standard protocols for sampling, extraction, enumeration and classification of MPs ingested by fishes have been developed and are presented here in order to enable worldwide comparisons. Standardized sample designs and laboratory procedures are an important strategy in order to establish comparisons among
Mário Barletta
added a research item
Research on estuarine ecology in South America (SA) increased quali-quantitatively since the early 1980 in search of consistent recommendations for estuarine conservation. The most important ecological theory achieved is that the seasonal fluctuation of the salinity gradient creates an ecocline influenced by gradual changes between river-dominated to marine-like waters. Estuarine fish fauna adapts to these changeable abiotic characteristics, including the spatial, and seasonal bioavailability of dissolved oxygen and numerous pollutants. However, studies on the influence of the estuarine ecocline are still missing for key estuarine systems. This study provides an overview of fish ecology and anthropogenic impacts within estuarine systems of SA and discusses priorities for environmental conservation. Research on fish reached important conclusions regarding essential habitats and fish interaction with other biological and abiotic compartments over spatio-temporal settings, including conditions of severe anthropogenic impacts. These impacts are related to unplanned urban settlements, industrial estates, ports, damming of major rivers, dredging activities, and deforestation for extensive farming. Changes in estuarine morphology alter natural flows and lead to habitat losses, disrupting the ecocline and impairing fishes from moving among formerly connected habitats, especially earlier ontogenetic phases. In addition, industrial, urban, and farming activities often result in high loads of metals and persistent organic pollutants, organic enrichment and oxygen depletion. Moreover, plastic debris, a ubiquitous contaminant with sources on every human activity, including fishing, when fragmented into microplastics, become preferably concentrated in semi-enclosed environments, as estuaries. Metals, POPs and microplastics are actually asserted to be persistent. When in high concentrations, they become bioavailable to the estuarine trophic web through bioaccumulation, being biomagnified or biotransfered toward higher trophic level organisms, such as top predator fishes. Therefore, research on environmental quality and fish ecology must be based on robust sampling designs along the whole ecocline using long-term approaches. In addition, basic sanitation, co-management, an improved Barletta and Lima Ecology and Conservation of South American Estuaries licensing system and scientifically-based risk assessments/monitoring for all sorts of enterprise are also urgent. These conservation priorities need to be in place before human-driven changes surpass the ecosystem's capacity to produce resources and maintain services.
Mário Barletta
added a research item
Estuarine pollution imposes rapid, increasing and lasting environmental modifications. In the present review, especial attention is given to estuaries in South America (SA), where legislation, policies and actions to guarantee environmental quality remain ineffective. There, the majority of estuaries face uncontrolled occupation of its margins by urban and industrial centres, agriculture and aquaculture expansion, water extraction and flow control. The lack of basic sanitation and poor environmental management (including territories within Marine Protected Areas) often lead to hydrological alterations, high nutrient loads, and the presence and dynamics of pollutants (nutrient loads, persistent organic pollutants (POPs), metals and plastic debris) along the entire estuarine ecocline.Organic enrichment has increased dissolved oxygen consumption, withwide spatio-temporal variability along latitudes and estuarine gradients. The toxicity, biogeochemistry and availability of metals and POPs depend on the annual fluctuations of salinity, water renewal, dissolved oxygen levels, suspended particulate loads, sediment mobility, grain size and composition at the sink. Plastic debris from land sources are widespread in estuaries,where they continue to fragment into microplastics. River basins are themain contributors of plastics to estuaries, whose transportation and accumulation are subjected to interannual water flow variations. Although some systems seems to be in a better condition in relation to others around the world (e.g. Goiana and Negro estuaries), many others are among the most modified worldwide (e.g. Guanabara Bay and Estero Salado System).We propose that, estuarine conservation plans should consider year-round fluctuations of the ecocline and the resulting cycles of retention and flush of environmental signals and their influence on trophic webs over the whole extent of estuarine gradients.
Gabriel E Machovsky-Capuska
added a project goal
About this Research Topic
The ‘Aquatic Habitat Conservation in South America’ Symposium occurred during the XXI Brazilian Society of Ichthyology Meeting. The proceedings were published as a special issue in the Journal of Fish Biology (vol. 89, Number 1, June 2016). In this special issue, authors provided an analytical overview of problems faced by the conservation of fishes and aquatic habitats of South America. Habitat loss emerged as the greatest concern for all South American aquatic ecosystems, with a long list of causes related to unsustainable development models.
Based on this finding, we would like to extend this topic to other continents, different climates, fauna and flora around the world. Our goal is to provide a comprehensive and multidisciplinary overview of variables that influence flora and fauna distributions and shape their ecological interactions within aquatic ecosystems.
Thereby, this Research Topic aims to provide a discussion forum to better understand the factors that lead to the loss of aquatic habitats and its effect on aquatic communities and ecosystem functioning, as well as the efforts being made to promote restoration of these ecosystems.
All topics related to aquatic habitat (marine and freshwater) ecology and conservation are therefore welcome. Local studies, as well as national and international efforts, to preserve and restore the functionality of aquatic ecosystems are invited and can be presented in the form of current research methods and findings, review articles, opinion pieces or expanded case studies and pilot programs designed to better understand the best practices of aquatic ecosystems management and restoration.
Keywords: Ecology, Aquatic Conservation, Climate change, habitat loss, microplastics
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.
Submission deadlines
01/02/2018 Abstracts
01/11/2018 Manuscripts