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Harwell Mark A. Gentile John H. Bartuska Ann Harwell Christine C. Myers Victoria Obeysekera Jayantha Ogden John C. Tosini Stephen C. 《Urban Ecosystems》1999,3(3-4):201-222
The Everglades and associated coastal ecosystems of South Florida are unique and highly valued ecosystems. One of the world's largest water management systems has been developed in South Florida over the past 50 years to provide flood control, urban and agricultural water supply, and drainage of land for development. However, this system has inadvertently caused extensive degradation of the South Florida environment, resulting in the loss of more than half the historical Everglades system and elimination of whole classes of ecosystems. The U.S. Man and the Biosphere Program (US MAB) instituted a project to develop ecosystem management principles and identify requirements for ecological sustainability of South Florida. A strategic process developed by the US MAB Project illustrates how ecosystem management and ecological risk assessment principles apply to South Florida, including the development of societal goals and objectives of desired sustainable ecological condition, translation of these goals/objectives into scientifically meaningful ecological endpoints, creation of a regional plan designed to meet the sustainability goals, and development of a framework for evaluating how well the plan will achieve ecological sustainability of South Florida. An extensive federal, state, and tribal interagency process is underway to develop a restoration plan for restructuring the regional management system, essentially following the elements in the US MAB project process. The Florida Governor's Commission was established as an institution to reflect societal values and define regional sustainability goals. The U.S. Army Corps of Engineers is developing a science-based plan for Congressional approval to restructure the water management system to achieve the societal goals. Thus, South Florida may become the prototype example of successful regional-scale ecosystem management. 相似文献
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Jenkins M Flynn A Smart T Harbron C Sabin T Ratnayake J Delmar P Herath A Jarvis P Matcham J;PSI Biomarker Special Interest Group 《Pharmaceutical statistics》2011,10(6):494-507
Biomarkers play an increasingly important role in many aspects of pharmaceutical discovery and development, including personalized medicine and the assessment of safety data, with heavy reliance being placed on their delivery. Statisticians have a fundamental role to play in ensuring that biomarkers and the data they generate are used appropriately and to address relevant objectives such as the estimation of biological effects or the forecast of outcomes so that claims of predictivity or surrogacy are only made based upon sound scientific arguments. This includes ensuring that studies are designed to answer specific and pertinent questions, that the analyses performed account for all levels and sources of variability and that the conclusions drawn are robust in the presence of multiplicity and confounding factors, especially as many biomarkers are multidimensional or may be an indirect measure of the clinical outcome. In all of these areas, as in any area of drug development, statistical best practice incorporating both scientific rigor and a practical understanding of the situation should be followed. This article is intended as an introduction for statisticians embarking upon biomarker-based work and discusses these issues from a practising statistician's perspective with reference to examples. 相似文献
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Obeysekera Jayantha Browder John Hornung Lewis Harwell Mark A. 《Urban Ecosystems》1999,3(3-4):223-244
Developing hypotheses for sustainability requires an understanding of the natural forces that shaped the historical Everglades prior to extensive engineering of the landscape. The historical Everglades marsh covered 10,000 km2 in a 100-km-long basin that has an extremely low gradient (slope of only 3 cm · km-1). The region is characterized by a heterogeneous landscape that has developed over the past five millennia, functioning as an interconnected mosaic of wetland, upland, estuarine, and marine ecosystems. The boundaries of this system were defined as the historic drainage basin from the Kissimmee River system through Lake Okeechobee, the Everglades, Florida Bay, and out through the Florida Keys to the coral reef tract. This geographic area is interconnected through the regional hydrology, with its unifying surface and subsurface freshwater transport system. However, in the final analysis, the interaction of geologic and climatic processes determine the system's hydrology, a major determinant of community and landscape structure and the point of connectivity between natural and human systems. This review examines the role of climate, geology, soils and sediments, topography, and hydrology in shaping and modifying ecological systems through time. However, it is clear from the wetland nature of this system that the predrainage hydrologic features were critical to the sustainability of the Everglades. Important hydrologic features include sufficient water quantity, storage, and sheetflow, and the appropriate hydroperiod and timing of water releases over both annual and interannual variations in precipitation. 相似文献
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