RESUMEN
In 2014, a DNA-based phylogenetic study confirming the paraphyly of the grass subtribe Sporobolinae proposed the creation of a large monophyletic genus Sporobolus, including (among others) species previously included in the genera Spartina, Calamovilfa, and Sporobolus. Spartina species have contributed substantially (and continue contributing) to our knowledge in multiple disciplines, including ecology, evolutionary biology, molecular biology, biogeography, experimental ecology, biological invasions, environmental management, restoration ecology, history, economics, and sociology. There is no rationale so compelling to subsume the name Spartina as a subgenus that could rival the striking, global iconic history and use of the name Spartina for over 200 yr. We do not agree with the subjective arguments underlying the proposal to change Spartina to Sporobolus. We understand the importance of both the objective phylogenetic insights and of the subjective formalized nomenclature and hope that by opening this debate we will encourage positive feedback that will strengthen taxonomic decisions with an interdisciplinary perspective. We consider that the strongly distinct, monophyletic clade Spartina should simply and efficiently be treated as the genus Spartina.
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Poaceae , FilogeniaRESUMEN
The use of nature-based infrastructure (NBI) has attracted increasing attention in the context of protection against coastal flooding. This review is focused on NBI approaches to improve coastal resilience in the face of extreme storm events, including hurricanes. We not only consider the role of NBI as a measure to protect people and property but also in the context of other ecological goods and services provided by tidal wetlands including production of fish and shellfish. Although the results of many studies suggest that populated areas protected by coastal marshes were less likely to experience damage when exposed to the full force of storm surge, it was absolutely critical to place the role of coastal wetlands into perspective by noting that while tidal marshes can reduce wave energy from low-to-moderate-energy storms, their capacity to substantially reduce storm surge remains poorly quantified. Moreover, although tidal marshes can reduce storm surge from fast moving storms, very large expanses of habitat are needed to be most effective, and for most urban settings, there is insufficient space to rely on nature-based risk reduction strategies alone. The success of a given NBI method is also context dependent on local conditions, with potentially confounding influences from substrate characteristics, topography, near shore bathymetry, distance from the shore and other physical factors and human drivers such as development patterns. Furthermore, it is important to better understand the strengths and weaknesses of newly developed NBI projects through rigorous evaluations and characterize the local specificities of the particular built and natural environments surrounding these coastal areas. In order for the relevant science to better inform policy, and assist in land-use challenges, scientists must clearly state the likelihood of success in a particular circumstance and set of conditions. We conclude that "caution is advised" before selecting a particular NBI method as there is no "one size fits all" solution to address site-specific conditions.
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Inundaciones , Humedales , Tormentas Ciclónicas , Ecología/métodos , Ecosistema , HumanosRESUMEN
The bioaccumulation and biomagnification of sediment-bound hydrophobic organic contaminants (HOCs) are of major concern for environmental and human health. In dynamic estuaries, HOCs can be taken up from sediments, porewater, or the overlying water column concentrations directly or via the diet. The transfer of HOCs including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) to resident/migratory biota was investigated in 11 finfish species and blue crabs (Callinectes sapidus) in the Passaic River estuary. Concurrently, passive samplers were deployed to assess porewater and overlying water column concentrations. Biota were assigned to three trophic levels based on their tissue 15N isotope values and published life history strategies. There were no significant differences in trophic magnification factors (TMFs) calculated based on life-history scenarios, implying that the migratory species, mostly juveniles, had equilibrated with in situ sources of pollutants at the time they were sampled. Bioaccumulation factors and TMFs were >1 for most PCBs and tetra- and penta-CDD/DFs, indicating that they underwent biomagnification in the food web. All PAHs, PCB 11, and other lower chlorinated PCBs and PCDD/Fs did not magnify. Results from the analysis of HOC profiles implied that biota accumulated HOCs from sediments, porewater, and diet but not from overlying water.
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Cadena Alimentaria , Sedimentos Geológicos/química , Ríos/química , Contaminantes Químicos del Agua/química , Adolescente , Animales , Braquiuros , Dioxinas , Estuarios , Peces , Humanos , New Jersey , Bifenilos Policlorados/análisis , Hidrocarburos Policíclicos Aromáticos/análisisRESUMEN
Twelve sediment cores were collected in July 2007 in open waters of western Bohai Bay, the Port of Tianjin, and the adjacent estuaries of the Haihe and Yongding Rivers. While overall concentrations of trace metals at incremental depths in these cores met the Marine Sediment Quality (GB18668-2002) criteria of China, the magnitude of both metal enrichment factors (EF) and geoaccumulation indices (I(geo)) suggested that pollution with Ag, Cd, Cr, Cu and Zn was occurring in the estuaries and Port. Risk analysis also suggested that Ag and Ni concentrations were sufficiently elevated as to cause adverse biological effects in the study area. Although metal concentrations in western Bohai Bay were of less concern, a positive relationship between EF values and excess (210)Pb activity for several metals suggested that their concentrations were increasing over time.
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Sedimentos Geológicos/análisis , Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis , Contaminación Química del Agua/análisis , Análisis de Varianza , China , Medición de Riesgo , Agua de Mar/análisisRESUMEN
This paper is based on a facilitated Workshop and Roundtable Discussion of key issues in sediment toxicology and ecological risk assessment (ERA) as applied to sediments that was held at the Conference on Dredged Material Management: Options and Environmental Considerations. The issues addressed included how toxicity is defined and perceived, how it is measured, and how it should be used within the context of ERA to support management decisions. The following conclusions were reached regarding scientific considerations of these issues. Toxicity is a measure of hazard and not a risk per se. Thus, toxicity testing is a means but not the end to understand risks of sediments. Toxicity testing cannot presently be replaced by chemical analyses to define hazard. Toxicity test organisms need to be appropriate to the problem being addressed, and the results put into context relative to both reference and baseline comparisons to understand hazard. Use of toxicity tests in sediment ERAs requires appropriate endpoints and risk hypotheses, considering ecological not just statistical significance, and recognizing that hazard does not equate to risk. Toxicity should be linked to population and community response to support decision-making, assessing possible genotypic adaptations that can influence risk estimates, and addressing uncertainty. Additionally, several key scientific issues were identified to improve future sediment ERAs, including the need to improve basic understanding of ecological mechanisms and processes, recognition of variability in the assessment process, and an improved focus and ability to assess risks to populations and communities.