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December 27, 2012

Sample Aqua Culture Essay


                                           Aquaculture farms in Estuaries
As much as sixty percent of humanity lives on the mouth of rivers or on the surrounding coastline. Agriculture, fisheries, tourism industry and urbanization are competing in the deltas and estuaries. But these areas also represent rich and fragile ecosystems, endangered by pollution, dams and oil exploration. With global warming and rising sea level, some deltas may even be completely flooded. 
            An entire country, Bangladesh, is based on the largest delta in the world. Tokyo, Calcutta, Rangoon and Alexandria are located on the edge of a delta. Out of 28 estuaries in the United States, 25 are suffering from decline or loss of species, 21 have an imbalance in nutrients, 20 are contaminated with pathogens and 19 with toxic substances. With global warming, the deltas of the Po, Nile, Mississippi, the lagoon of Venice and others, are threatened by rising waters.
Deltas and estuaries are characterized by a remarkable number of plants and animals. They are conducive to the development of rich media, such as salt marshes and mangrove forests. Number of species (fish, mollusks, crustaceans) freshwater and brackish environments typical of other live together, and mammals (otters, dolphins, manatees) and aquatic reptiles (crocodiles, turtles).Juveniles of many fish species have extended stays in estuaries. They are a sanctuary for some migratory species such as salmon, shad and eels. The migrating birds have their stopovers in deltas and estuaries for food which they find in abundance here or in some cases settle down to join the great variety of resident birds.(Naylor, 2001) 
These territories have multiple functions: coastal nursery essential for the renewal of fish stocks; treatment, storage, processing and regulation of pollutants and other waste materials brought from the upstream area of
​​major habitat for birds and flora associated intertidal Wetlands; regulation of rainfall and local humidity through transpiration, and also an important food source for humanity. Aquaculture and fisheries were intensively developed in the aquatic environment rich in phytoplankton.
  Port industries and continental oil drilling, fishing, aquaculture and tourism  pose multiple threats to these environments. The exploration of oil and gas, abundant in the delta because of their geology, rejects the sludge-laden oil. The pollution carried by rivers flow into these territories. Waste from industry, agriculture, the city is concentrated in the sediments, including heavy metals like cadmium, lead, zinc and mercury, as well as detergents, pesticides and other biocides, chlorine , microbiological contaminants (pathogens and toxic plankton). The cadmium content of wild oysters from the Gironde, despite having fallen sharply since 1980, remains high: 10 to 30mg per g of flesh (maximum prescribed 1 mg / kg). The decanting and diversion of rivers for irrigation and navigation, severely damaging the dynamics of river deltas and estuaries, rivers, some even arriving to the sea The diversion of Colorado, for example, has reduced the flow upon arrival in the Gulf, amending the landscape, disrupting the ecosystem, with declining populations of fish, invertebrates and marine mammals.
             The dam, originally created to regulate water flow and build reserves in anticipation of dry spells, particularly for agriculture, have caused an erosion of the delta of waterborne diseases (cholera, typhoid, polio, meningitis, hepatitis A and E, diarrhea), disruption of fishing activities, water loss by evaporation and algal blooms,. Overfishing is negatively affecting fish populations, some species are endangered (shad, sturgeon).

Nevertheless, aquaculture in estuaries is rife with potential for economic and environmental growth but its effectiveness hinges on its regulations and proper management. The degradation of the environment increases the stress and the frequency of disease of livestock thus reducing the productivity. The expansion of intensive bivalve agriculture in estuaries can cause environmental damage if it is not properly managed and regulated.
   The degree of interaction between aquaculture farm and environment depends on the sensitivity of the ecosystem where it is located. Future expansion of aquaculture farms in estuaries should be based on balanced interventions within the framework of coastal management.(Hepburn, 2001)
    While discussing the importance of aquaculture farms in estuaries, it should be kept in mind that this industry is relatively new and its development has coincided with an increase in awareness of environmental problems. Unlike other industries, it heavily depends on natural aquatic resources and quality environment. (Duarte, 2007)
   However, it may have negative impacts on the environment. For examples, it is accused of disrupting navigation, polluting the coastal environment and transmitting diseases and parasites to the fish population. On the positive side, it is less friendly to the environmental pollution or degradation of natural habitat. It should be noted that wherever the aquaculture projects in estuaries were launched, the choice of an improper site and poor management were often blame instead of the project itself.
  Most of the regulations protect the established activities. In many countries, laws and regulations on aquaculture farms are inadequate and do not fully address the core problems related to it. These laws and regulations are often not particularly beneficial to the integration of aquaculture and other activities.
  Conflicts for space may come about among traditional aquaculture especially shellfish, oysters and mussels and also other species like fishes and mules. The shellfish and fish can be ravaged by diseases caused by the pathogens. In addition, treatment with antibiotics and antifouling substances performed in the aquaculture farms in estuaries can leave harmful effects on the shellfish products lying in proximity.
            The point is that aquaculture farming is highly dependent on a healthy environment and is also the best quality assurance of the latter. The environment must be considered before the beginning of any project. However, over-regulation should be avoided in favor of less conscious environment. Aquaculture can be of greater interest in terms of use of space, stabilization and prosperity of the population and better use of renewable resources. Therefore, instead of banning the whole activity, it is urgent to implement legitimate development strategies and planning.
  
   The procedures for the selection of sites related to coastal planning and development particularly in a climate of competition for the use of coastal space and resources should be chalked out. Aquaculture farming in estuaries should be considered a significant coastal activity therefore a well-planned strategy should be put in place for its development and preservation.
 The environmental management should consider it as an important activity and utilize the necessary resources for that matter. It would harmonize the relationship between the development of aquaculture, coastal resources, and their users.

    When the schedule is decided, a specific procedure must be established including the delineation of areas of interest, the research database on the environmental studies in order to determine the fitness and durability of the project. Proper regulation is necessary to development of sustainable aquaculture and its integration into coastal development. 
   The use of space and the management activities demands relevant planning tools that are specific to each country and in relation to policy priorities and administrative organization. Therefore, their application should be more decentralized.  
 
            The role of aquaculture in estuaries is to develop conscious activity interdependencies such environment/production and allow it to integrate into the ecosystem. Aquaculture could benefit from the integration of above stated factors. The negative impact on estuaries can be minimized through aquaculture techniques which are in harmony and compatible with the environment and nature.   
    The development of aquaculture may also face social constraints. Urbanization can bring new ways of living, where consumption of fresh fish and shells can be replaced by a new type of human nutrition (products and frozen foods, high quality). The system education of current fishing could have a positive effect on the formation of new aquaculturists. However, competition between farmers and fishermen could grow particularly in areas of low stand.
    The new aquaculture techniques require qualified expertise, obtained during specialized courses. This learning system may be of interest to workers sea ​​(fishermen, fish farmers traditional). However, where the workforce is somewhat abundant, the competition between different activities could occur following the transfer employment towards each other. 
The establishment of a licensing system 
allows the creation of provisions administration can be pro- aquaculture management and tracking of water quality (bacteriological standards, 
toxic algae, heavy metals, pesticides)
  Coastal economists, general public and surrounding coastal communities generally lack efficient transfer of information which is considered a major obstacle towards the integration of aquaculture into policies for integrated management of coastal zones and strategies for resource allocation. 
    Economic resources available to developing aquaculture farms are influenced 
positively by the attraction of investments and infrastructure (roads, electricity, supply) connected to the industry, urbanization and tourism. Fishing near areas of aquaculture can 
also have a positive side to it promoting the seafood and meeting its increasing demand. A sound policy and planning should be able to clearly define the opportunities and limitations of aquaculture farms in estuaries accordingly.


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