Long‐term studies along a 30‐yr nutrient‐enrichment gradient in the northern part of the subtropical Everglades fen allowed us to assess the effects of nitrogen (N) and phosphorus (P) additions on plant community structure and chemical qualities of wetland plants. Areas in the highest P‐enriched zones (>1000 mgP/kg), once dominated by open‐water sloughs and surrounding monocultures of sawgrass (Cladium jamaicense, a stress‐tolerant low‐nutrient‐status species), are now dominated by cattail (Typha domingensis, a competitive, high‐nutrient‐status species). Areas of moderate (750–500 mg/kg) and low (<500 mg/kg) P soil concentrations have maintained their original plant composition. Analysis of nutrient‐use efficiency indicates that sawgrass is highly efficient in nutrient resorption and nutrient proficiency, but this efficiency decreases at high soil P concentrations. Both indices indicate that suboptimal concentrations of P, which limit growth and optimize retention of P within the plant, exist in the Everglades. This information, when coupled with the low levels of P found in the plants, soil, and pore water of the unenriched portions of the Everglades, indicates that this ecosystem is extremely P limited. High molar N:P leaf ratios suggested P limitations for sawgrass at unenriched sites, but not in highly enriched areas. Intermediate P loadings resulted in either N or P limitations. Increased leaf P concentrations correspond to decreased phenolic content of sawgrass leaves, suggesting that this species’ metabolic growth response follows the carbon–nutrient balance hypothesis of decreased production of phenolics with increased nutrient supply. Concomitant with decreased foliar phenolic content at high P enrichment was an increase in herbivory and fungal infections.

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. Ecological Society of America is collaborating with JSTOR to digitize, preserve and extend access to Ecology.Abstract. Long-term studies along a 30-yr nutrient-enrichment gradient in the northern part of the subtropical Everglades fen allowed us to assess the effects of nitrogen (N) and phosphorus (P) additions on plant community structure and chemical qualities of wetland plants. Areas in the highest P-enriched zones (>1000 mgP/kg), once dominated by openwater sloughs and surrounding monocultures of sawgrass (Cladium jamaicense, a stresstolerant low-nutrient-status species), are now dominated by cattail (Typha domingensis, a competitive, high-nutrient-status species). Areas of moderate (750-500 mg/kg) and low (<500 mg/kg) P soil concentrations have maintained their original plant composition. Analysis of nutrient-use efficiency indicates that sawgrass is highly efficient in nutrient resorption and nutrient proficiency, but this efficiency decreases at high soil P concentrations. Both indices indicate that suboptimal concentrations of P, which limit growth and optimize retention of P within the plant, exist in the Everglades. This information, when coupled with the low levels of P found in the plants, soil, and pore water of the unenriched portions of the Everglades, indicates that this ecosystem is extremely P limited. High molar N:P leaf ratios suggested P limitations for sawgrass at unenriched sites, but not in highly enriched areas. Intermediate P loadings resulted in either N or P limitations. Increased leaf P concentrations correspond to decreased phenolic content of sawgrass leaves, suggesting that this species' metabolic growth response follows the carbon-nutrient balance hypothesis of decreased production of phenolics with increased nutrient supply. Concomitant with decreased foliar phenolic content at high P enrichment was an increase in herbivory and fungal infections.

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Multiply By To obtain mile (mi) 1.609 kilometer (km) square mile (mi 2) 2.590 square kilometer (km 2) million gallons per day (Mgal/d) 0.04381 cubic meter per second (m 3 /s) Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83). Concentrations of chemical constituents in water are given in micrograms per liter (μg/L) unless otherwise noted.

background and compliance monitoring programs, and water-purity analyses. The Department of Health (wvc, section 16-1) is responsible for the protection of drinking-water supplies, including the regulation of all drinking-water wells, both public and private. The Environmental Engineering Division of the WVDH has primacy for the "Safe Drinking Water Act" to develop laws, design standards, policies, and regulations for public water supplies. This Division also has the authority to enforce drinking-water standards for publicwater systems, to issue construction and operating permits for public water systems, and to train and certify well drillers and public watersupply operators. The WVDH laboratories perform chemical, bacteriological, and radiological analyses of drinking water on a routine basis for public water supplies and, at the request of county health departments, for private water supplies. County health departments are responsible for site inspection and issuance of permits for construction of domestic water wells and sampling for contaminants. The county health departments also are responsible for inspection and issuance of permits for the installation and operation of septic-tank systems and other onsite sewage-disposal systems, as well as the regulation of septic disposal. The Department of Energy, created in 1985, is responsible for the regulation of the coal, petroleum, and natural gas industries (wvc, §22). The Division of Mining and Minerals requires mine operators to prevent or minimize degradation of the quality and quantity of groundwater resources. The Oil and Gas Division is responsible for preventing the contamination of freshwater by saltwater and by other contaminants associated with the oil and gas industry. The Department of Agriculture, Plant Pest Control Division, is involved with the usage of pesticides. Responsibilities include training and certification of pesticide applicators, establishment of standards for powerline and right-of-way spraying, and investigation of groundwater complaints involving pesticide contamination. Other activities of the Department of Agriculture related to ground water include dispensing information about proper disposal practices for agricultural wastes, such as fertilizers, manure, and dead animals. The Department of Highways (DOH) is responsible for the prevention of contamination of ground water by highway deicing materials and highway runoff, the regulation of salvage yards (wvc, section 17-23), and the management of materials stored at DOH maintenance facilities. The Water Resources Board (WRB) is an independent agency composed of five members appointed by the Governor.