2017年-世界发展银行全球_An_Overview_of_Agricultural_Pollution_in_Vietnam___The_Aquaculture_Sector_48页_1mb

Summary of "An Overview of Agricultural Pollution in Vietnam: The Aquaculture Sector" (2017)

Core Content

This report is part of the World Bank's Regional Agricultural Pollution Study, focusing on the aquaculture sector in Vietnam. It outlines the environmental challenges posed by aquaculture practices, particularly in the context of growing production and intensification, and identifies key areas for policy and management improvement.

Main Points

1. Introduction

• Background: Aquaculture is a vital and expanding component of Vietnam's agricultural economy.
• Analytical Framework: The report uses an analytical framework to evaluate pollution sources, impacts, and drivers in the aquaculture sector.
• Roadmap: The report is structured into eight sections, covering aquaculture trends, environmental impacts, drivers, responses, and recommendations.

2. Overview of Aquaculture in Vietnam

• Trends in Farmed Area and Production:
  • Total aquaculture area increased from 453,000 ha in 1995 to over 1.2 million ha by 2020.
  • Aquaculture production grew from 1995 to 2013, increasing eightfold, reaching 3.2 million tons in 2013.
  • The Mekong River Delta (MKD) is the most important region for aquaculture, accounting for 63-73% of the total area.
  • Production is heavily concentrated in the MKD, which contributes 60-75% of national output.
• Fisheries Master Plan to 2020:
  • The plan aims for aquaculture to contribute 65-70% of total fisheries production and 30-35% of GDP from the agriculture-forestry-fisheries sector.
  • By 2020, aquaculture is expected to produce over 4.5 million tons, with a focus on export-oriented species like Pangasius and shrimp.
  • Specific targets include increasing seafood export value to US$11 billion and reducing postharvest losses in marine catch to below 10%.

3. Polluting Effects of Pangasius and Shrimp Farming

• Pangasius Farming:
  • Intensive Pangasius farming uses large amounts of freshwater and generates significant waste.
  • High stocking density (18-125 fish/m²) and feeding rates contribute to pollution.
  • Feed conversion ratio (FCR) is around 1.6 for commercial feeds, with 37-38% of feed ending up as waste.
  • Waste includes uneaten feed and excreta, which accumulate in pond water and mud, leading to water quality degradation and sedimentation.
• Shrimp Farming:
  • Intensive shrimp farming, especially black tiger shrimp, is a major source of pollution.
  • Key practices include pond construction, water exchange, and the use of chemicals and drugs.
  • Shrimp farming areas are mainly located in the MKD, with 91% of black tiger shrimp farms and 70% of white-leg shrimp farms in the region.
  • Intensive systems have high stocking density (up to 0.5 ha), while extensive systems are larger (1-3 ha) with lower density.

4. Impacts of Aquaculture Pollution

• Surface Water Quality: Pollution affects water quality, leading to reduced dissolved oxygen and increased biochemical and chemical oxygen demand.
• Human and Ecosystem Health: Contaminated water and sediments pose risks to both human health and biodiversity.
• Food Safety: Use of antibiotics and chemicals in aquaculture raises concerns about drug-resistant microbes and food safety.
• Groundwater Availability: Aquaculture practices affect groundwater, which is essential for both farming and other activities.
• Saline Intrusion: Intensive aquaculture in coastal areas contributes to saline intrusion, impacting agricultural productivity.

5. Drivers of Aquaculture Pollution

• Intensification of aquaculture practices.
• High stocking density and feed usage.
• Poor waste management and lack of environmental regulations.
• Use of chemicals and antibiotics in farming and processing.
• Expansion of aquaculture into sensitive ecosystems like mangroves.

6. Existing Responses and Potential Solutions

• Public Sector Responses:
  • Government agencies have implemented policies and regulations to manage aquaculture pollution.
  • Environmental Impact Assessments (EIAs) are required for new aquaculture projects.
  • The Department of Agriculture and Rural Development (DARD) and the Ministry of Natural Resources and Environment (MONRE) are involved in managing these issues.
• Private Sector Responses:
  • Some private companies have adopted sustainable practices, such as contract farming and better waste management.
  • There is a growing trend towards Good Aquaculture Practices (GAP) and Vietnam's Good Aquaculture Practices (VietGAP).

7. Data and Evidence Gaps

• Data Gaps: Limited availability of comprehensive and up-to-date data on pollution levels and sources.
• Knowledge Gaps: Need for more research on the environmental and health impacts of aquaculture, particularly in the context of climate change and biodiversity loss.

8. Conclusions and Recommendations

• The aquaculture sector is a significant contributor to environmental pollution in Vietnam.
• Intensification leads to increased waste generation and environmental degradation.
• The report recommends improving waste management, strengthening regulations, and promoting sustainable practices.
• It emphasizes the need for better data collection and monitoring, as well as collaboration between the public and private sectors to reduce pollution.

Key Species and Systems

Conclusion

Vietnam's aquaculture sector, particularly Pangasius and shrimp farming, has experienced significant growth but at the cost of environmental degradation. The report highlights the need for improved management practices, better data collection, and policy interventions to ensure the sustainability of aquaculture while protecting the environment and public health.