Environmental impacts of shrimp farming on coastal ecosystem of east Godavari district

Abstract

The Coastal Ecosystem provides various types of ecosystem services such climate regulation at global level, commercial fisheries at regional scale, food security and livelihoods to coastal communities and recreational opportunities at local level. The composition of these coastal ecosystem services were completely changed from certain time, as these coastal ecosystems have responded to natural and anthropogenic stresses. Over exploitation of goods and services from the coastal ecosystems are under stress from different types of sources such as overfishing, pollution, coastal development and shrimp farming etc. There are different zones which comes under the Coastal Ecosystem such as Near Shore Terrestrial Zone (Dunes, Cliffs, rocky & sand shores, Urban & Rural settlements up to 14 km), Inter Tidal Zone (Estuaries, Mangrove Forests, Mud Flats, Salt pans, sea grass, lagoons and corals), Benthic Zone (Sea grass meadows, seaweed ecosystems, coral reefs) and Pelagic Zone (Open Waters above continental shelf). The study is limited to the Mangrove Forests, Mudflats, urban and rural settlements up to 14km from Mangrove Forests. Mangrove Forests are known for being one of the most productive and biologically diverse on the planet. These mangrove forests are located at the shorelines of the coastal areas which provide wildlife and humans with various resources and ecological services such as forest products, habitat, water purification, shoreline stabilization, coastal protection and carbon sequestration. Despite of the importance and value of the mangrove forests, these have been damaged due to the development of shrimp farming and industries which are posing a great threat to mangrove forests. Shrimp Farming is the present major threat to mangrove forest and their destruction leads to environmental and social problems. The present shrimp farming methods are clearing the mangroves and changes the waterways to build shrimp farms. The run off which consists of chemicals and waste from the shrimp farms posing a negative impact on the both mangrove area and surrounding agricultural land which results in loss of goods and services. The local communities who depend on the mangrove forests for their livelihoods are suffer a lot from these unsustainable shrimp farming practices. This study area is located in the mangrove region of East Godavari District (16°57′N 82°15′E) of Andhra Pradesh. Using Geographical Information System, land use maps have been generated for the years 1990, 2003 and 2017. The aerial images from Google Earth for the above years were compared to analyse the temporal changes occurred. This has revealed that the shrimp farming has been increased from 3036.93 ha to 7895.22 ha which are mainly built on the mangrove forests and agricultural land. The main aim of this project is to assess the environmental impacts of shrimp farming on the Coastal Ecosystem of East Godavari District and to promote the use of sustainable practices of shrimp farming such as integrated mangrove shrimp farming. The Environmental impacts of shrimp farming on Coastal Ecosystem of East Godavari are loss of mangrove cover, decreased carbon sequestration, degradation of water and soil quality of agricultural land and mangrove region and loss of biodiversity. Policies, laws and sustainable integrated mangrove shrimp farming methods are needed to regulate the shrimp farming development in mangrove forests of East Godavari and reduce the impacts at local level. To achieve these local communities need to get involved to help restore the environmental quality of Coastal Ecosystem of East Godavari District.