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Strategic Assessment of Near Coastal Waters: Northeast Case Study
Get PDFThe Northeast Case Study has been undertaken to illustrate how data being developed in NOAA\u27s program of strategic assessments can be used for resource assessments of estuaries and near coastal waters throughout the contiguous USA. It was designed as a pilot project to assist the U.S. Environmental Protection Agency (EPA) in developing its Strategic Initiative for the Management of Near Coastal Waters. As part of this initiative, the coastal states and EPA are to identify estuarine and coastal waters that require management action. The project began in June 1987 as a cooperative effort by NOAA\u27s Office of Oceanography and Marine Assessment and EPA\u27s Office of Policy, Planning, and Evaluation and Office of Marine and Estuarine Protection. The Northeast was selected because NOAA\u27s data bases were more complete for the estuaries of this region at the time. Offshore areas are not included since information to characterize them has not been organized for a consistently defined set of spatial units. Preliminary and interim case study reports were completed in September and November 1987. In these reports, information was compiled by estuary for seven themes: (1) physical and hydrologic characteristics; (2) land use and population; (3) nutrient discharges; (4) classified shellfish waters; (5) toxic discharges and hazardous waste disposal sites; (6) coastal wetlands; and (7) public outdoor recreation facilities. Most of the information was compiled from NOAA\u27s National Coastal Pollutant Discharge Inventory, National Estuarine Inventory (Volumes 1 and 2), National Coastal Wetlands Inventory, and Public Outdoor Recreational Facilities Inventory. However, with the exception of the toxic discharges chapter in the interim report, only cursory explanations of the data and no data analyses were provided in the previous reports. Two chapters, nutrient and toxic discharges to estuaries, will be completed to illustrate fully the extent of available data, the methods used to develop the data, and the types of analyses that are possible. The data bases used to compile the information in the report are constantly being updated and improved. For example, during the course of the project, NOAA analyzed the susceptibility and status of all estuaries identified in its National Estuarine Inventory to nutrient and toxic discharges. This information, not in the preliminary and interim drafts of the case study, is emphasized in the chapters on nutrient and toxic discharges with special attention given to the estuaries in the Northeast. Case studies for other regions may be completed in the future depending on interest and available resources
Twenty Years Later
Get PDFLyrics for a song written in response to the Kent and Jackson State shootings, by singer and activist Holly Near
Molecular and fossil evidence place the origin of cichlid fishes long after Gondwanan rifting.
Get PDFCichlid fishes are a key model system in the study of adaptive radiation, speciation and evolutionary developmental biology. More than 1600 cichlid species inhabit freshwater and marginal marine environments across several southern landmasses. This distributional pattern, combined with parallels between cichlid phylogeny and sequences of Mesozoic continental rifting, has led to the widely accepted hypothesis that cichlids are an ancient group whose major biogeographic patterns arose from Gondwanan vicariance. Although the Early Cretaceous (ca 135 Ma) divergence of living cichlids demanded by the vicariance model now represents a key calibration for teleost molecular clocks, this putative split pre-dates the oldest cichlid fossils by nearly 90 Myr. Here, we provide independent palaeontological and relaxed-molecular-clock estimates for the time of cichlid origin that collectively reject the antiquity of the group required by the Gondwanan vicariance scenario. The distribution of cichlid fossil horizons, the age of stratigraphically consistent outgroup lineages to cichlids and relaxed-clock analysis of a DNA sequence dataset consisting of 10 nuclear genes all deliver overlapping estimates for crown cichlid origin centred on the Palaeocene (ca 65-57 Ma), substantially post-dating the tectonic fragmentation of Gondwana. Our results provide a revised macroevolutionary time scale for cichlids, imply a role for dispersal in generating the observed geographical distribution of this important model clade and add to a growing debate that questions the dominance of the vicariance paradigm of historical biogeography
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