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Issues in ecology: Nutrient pollution of coastal rivers, bays, and seas
Much of this eutrophication is due to increased inputs of nitrogen to coastal oceans. Over the past 40 years, antipollution laws have greatly reduced discharges of toxic substances into our coastal waters. Nonpoint pollution from N and P now represents the largest pollution problem facing the vital coastal waters of coastal pollution pdf download United States. This effort, however, has focused largely on point-source pollution of industrial and municipal effluent.
The past few decades have seen a massive increase in coastal eutrophication globally, leading to widespread hypoxia and anoxia, habitat degradation, alteration of food-web structure, loss of biodiversity, and increased frequency, spatial extent, and duration of coastal pollution pdf download algal blooms.
Coastal nitrogen pollution: A review of sources and trends globally and regionally – ScienceDirect
Given that pollutiln loads are projected to coastal pollution pdf download in future years, this study highlights the importance of prioritization and mitigation in coastal pollution management and demonstrates a method that could be sownload in other places with similar problems in the Wider Caribbean Region.
Also, action should be taken to assure that the 40 percent of coastal areas now ranked as healthy do not develop symptoms of nutrient pollution. N from animal wastes that leaks directly to surface waters or is volatilized to the atmosphere as ammonia may be the largest single source of N that moves from agricultural operations into coastal waters.
The rate of change in nitrogen use in agriculture is incredible, and over coastal pollution pdf download of the synthetic nitrogen fertilizer ever produced has been used in the past 15 years.
Coastal pollution pdf download is associated with BOD loads from canal discharges, psf and industrial waters. Coasfal some coastal systems, N removal during treatment of human sewage may be sufficient to reverse nutrient pollution.
Occasionally, inadequate recreational water quality can be attributed to nearby sources of domestic wastewater, which contribute the highest coliform load 6.
Check if you ldf access through your login credentials or your institution. For most coastal systems, however, the solutions will be more complex and may involve controls on N compounds emitted during fossil fuel combustion as well as incentives to reduce over-fertilization of agricul- tural fields and nutrient pollution from animal wastes in livestock feedlot operations.
While moderate N enrichment of some coastal waters may increase fish production, over-enrichment generally degrades the marine food web that supports commercially valuable fish.
Continental runoff via the Dique Canal contributes the greatest sediment load 2. Nutrient over-enrichment of coastal ecosystems generally triggers ecological changes that decrease the biologi- cal diversity of bays and estuaries. Given the lack of available data on discharges and coastal pollution pdf download quality, an integrated approach is applied by combining various methods of load estimation while emphasizing the importance of calculating confidence intervals for each load value.
Much of this increase has occurred over the past few decades. Atmospheric deposition of nitrogen from fossil fuel combustion also contributes to the global budget for reactive nitrogen and is the largest single source of nitrogen pollution in some regions. This coastal pollution pdf download is particularly severe in the mid Atlantic states, in the southeast, and in the Gulf of Mexico. The marked increase in nutrient pollution of coastal waters has been accompanied by an increase in harmful algal blooms, and in at least some cases, pollution has triggered these blooms.
Recommended coastal pollution pdf download Citing articles 0. Industrial loads were estimated based on previous studies.
Meeting these goals will require an array of strategies and approaches tailored to specific regions and coastal ecosystems. Domestic loads were computed using GIS analyses of population and sewerage coverage in combination with export coefficients of daily load per capita.
Results show that each type of land-based source is responsible for different pollution impacts observed in Cartagena Bay. Regional variation in this increase is great, and some regions of the Earth have seen little change, while in other areas, nitrogen fluxes through the atmosphere and through rivers have increased by 10—fold or more.
Abstract The past few decades have seen a massive increase in coastal eutrophication globally, leading to widespread hypoxia coastal pollution pdf download anoxia, habitat degradation, alteration of food-web structure, loss of biodiversity, and increased frequency, spatial extent, and duration of harmful algal blooms.
Pollution loads from nearby sources of coastal pollution pdf download wastewater, coastal industrial effluents and continental runoff were assessed with respect to their contributions of coliforms, total suspended solids, nitrogen, phosphorus, and biological oxygen demand BOD.
No comparable effort has been made to restrict coastal pollution pdf download input of nitrogen N from municipal effluent, nor to control the flows of N and phosphorus P that enter waterways from dispersed or nonpoint sources such as agricultural and urban runoff or as airborne pollutants.
Abstract Dowjload identification and prioritization of pollution sources is essential to coastal zone management.
Author links open overlay panel Robert W. Loads from the canal’s surface runoff coastal pollution pdf download calculated with monthly discharge and water quality data. More than 60 percent of our coastal rivers and bays in every coastal state of the continental United States are moderately to severely degraded by nutrient pollution. Both agriculture and the burning of fossil fuels contribute significantly to nonpoint flows of N to coastal waters, either as direct runoff or airborne pollutants.
There is an urgent need for development and testing of techniques that can reliably pinpoint the sources of N pollutants to an estuary.
Research during the past decade confirms that N is the chief culprit in eutrophication and other impacts coastal pollution pdf download nutrient over-enrichment in temperate coastal waters, while P is most problematic in eutrophication of freshwa- ter lakes. This study presents a methodology for the integrated assessment of anthropogenic pollution sources discharged into the coastal zone by estimating coastal pollution pdf download loads and comparing their relative contributions to receiving coastal waters.
Check if you have access through your login credentials or your institution. This task is complicated when a variety coastal pollution pdf download pollution sources are found and by limited data availability, which can result in an inconclusive assessment and differing public perceptions, ultimately hindering the progress of management actions. Before the advent of the industrial revolution and the green revolution, the rate of supply of nitrogen on Earth was limited to the rate of bacterial nitrogen fixation, but human activity now has roughly doubled the rate of creation of reactive, biologically available nitrogen on the land masses of the Earth.
Recommended articles Citing articles 0. As a result, inputs of nonpoint pollutants, particularly N, have increased dramatically. This is the case in Cartagena Bay Colombiaa Caribbean hot-spot of pollution, which receives large freshwater discharges from the Magdalena River drained via the Dique Canal along with coastal industrial effluents and untreated coastal pollution pdf download wastewater from parts of the coastal population. The integrated approach may be applied in similar coastal zones across the Coastal pollution pdf download Caribbean Region.
Technical solutions for reducing nitrogen pollution exist at reasonable cost, but implementation has been poor in many regions. The identification and prioritization of pollution sources is essential to coastal zone management.
High nutrient coastal pollution pdf download and the changes they cause in water quality and the makeup of the algal community are detrimental to the health of coral reefs and the diversity of animal life supported by seagrass and kelp communi- ties. Human conversion of atmospheric N into biologically useable forms, principally synthetic inorganic fertilizers, now matches the natural rate of biological N fixation from all the land surfaces of the earth.