2016年-世界发展银行全球_An_Overview_of_Agricultural_Pollution_in_the_Philippines___The_Livestock_Sector_2016_59页_2mb

Summary of Agricultural Pollution in the Philippines: The Livestock Sector

Core Content

This report provides an overview of agricultural pollution in the Philippines, focusing specifically on the livestock sector. It outlines the historical context, current status, environmental impacts, and interventions related to livestock and poultry farming, emphasizing the role of waste management in pollution control.

Main Points

1. Livestock Subsector Overview

The livestock subsector in the Philippines includes large and small ruminants, swine, and poultry. Large ruminants consist of cattle and carabao (water buffalo), while small ruminants include goats and sheep. Poultry includes layer, broiler, and native chickens, along with ducks and limited rearing of pigeons, turkey, and quail. There is also limited rearing of rabbits for meat.

2. Farm Classification

• Backyard farms:
  • Up to 20 heads for large and small ruminants.
  • Up to 20 heads for swine.
  • Up to 100 bird holdings for poultry.
• Commercial farms:
  • Exceed the above thresholds.
  • Commercial swine farming has grown significantly, increasing from 18% to 35% of the total swine inventory between 1994 and 2014.

3. Environmental Impacts

• Waste Management Pollution:
  • Improper handling, treatment, and disposal of animal waste (manure, urine, bedding, and leftover feed) lead to pollution.
  • Air pollutants from manure include ammonia, hydrogen sulfide, and VOCs.
  • Major GHGs from livestock include methane (CH₄) and nitrous oxide (N₂O), primarily from enteric fermentation and manure management.
• Water Pollution:
  • Nutrient runoff from manure contributes to eutrophication of surface water.
  • Nitrate leaching leads to groundwater contamination.
• Soil Pollution:
  • Excess nitrogen from manure causes nitrogen overload.
  • Heavy metals from livestock manure can accumulate in soil.

4. Waste Management Practices

• Manure Production:
  • Over 39 million tons of manure is produced annually.
  • Manure can be used as fertilizer if properly treated.
• Waste Treatment:
  • Swine Waste:
    • Conventional wash-and-flush methods contribute significantly to pollution.
    • Biogas digesters can convert manure into fuel and fertilizer.
  • Poultry Waste:
    • Relatively dry, making it easier to use as fertilizer.
  • Cattle and Carabao Manure:
    • Requires physical and biological treatments (e.g., composting, anaerobic digestion) for safe use.
  • Carcass Disposal:
    • Improper disposal can lead to microbial contamination of water sources.

5. Key Sectors and Trends

• Swine Industry:
  • Dominates the livestock sector, contributing 82% of the total value of production.
  • Most swine are raised in backyard farms (64% of total population as of 2015).
  • Commercial swine farms are concentrated in Regions 3 and 4A.
• Poultry Industry:
  • Leads the poultry sector, contributing 75% of the total value of production.
  • Broiler and layer chickens are primarily raised in commercial settings.
  • Native chickens are more common in backyard operations and are raised under free-range systems.
• Cattle and Carabao:
  • Backyard cattle account for 93% of the total cattle inventory.
  • Cattle farming has shifted from large ranches to smallholder farms due to reforestation and land conversion.
  • Carabao is primarily used for draft power and has a small percentage of dairy production.

6. Socioeconomic Impacts

• Human Health:
  • Poor waste management can lead to air and water pollution, affecting public health.
• Biodiversity:
  • Pollution from livestock can harm local ecosystems.
• Consumer Demand:
  • Environmental management practices influence consumer preferences, particularly for organic products.

7. Government Interventions

• Policies and Regulations:
  • The Livestock and Poultry Feeds Act, Food Safety Act of 2013, and DENR Administrative Order No. 30, Series of 2003 are key legal frameworks.
  • LLDA Resolution No. 169, Series of 2001 and Philippine Agricultural Engineering Standards guide waste management.
• Technology and Practices:
  • Composting and Vermicomposting help in converting manure into organic fertilizer.
  • Biogas Digesters enable the use of methane as fuel.
  • Built-up-litter systems in backyard farms reduce odor and improve waste management.

Key Information

• Annual Manure Production: Over 39 million tons.
• GHG Emissions:
  • Methane (CH₄) and nitrous oxide (N₂O) are major emissions from livestock.
  • Methane production from livestock and poultry is estimated at over 500,000 tons per year.
• Pollution Sources:
  • Point and non-point sources: BOD load from livestock waste is significant.
  • Nitrate Leaching: Affects groundwater quality.
• Regional Distribution:
  • Swine: Regions 3, 4A, and 6 are major contributors.
  • Poultry: Broilers and layers are concentrated in Regions 3, 4A, and 10.
  • Carabao: Region 7 has the highest population, followed by Regions 2, 3, 5, and 8.
• Pollution Management Challenges:
  • Coordination between local government units (LGUs) and national agencies is lacking.
  • Environmental concerns from other sectors (e.g., agriculture, industry) complicate pollution control efforts.

Conclusion

The livestock sector in the Philippines is a major contributor to agricultural output and pollution. While the industry has grown, especially in commercial operations, improper waste management practices remain a significant environmental challenge. Government policies and technological interventions are essential to mitigate pollution, but their implementation is hindered by coordination issues and the complexity of managing the entire livestock value chain. Improving waste treatment and promoting sustainable practices such as composting and biogas production are critical steps towards reducing the environmental footprint of livestock farming.