Philippine agriculture stands at a crossroads. Long celebrated as the backbone of rural livelihoods, it is now confronted with a dual reality: it is both highly vulnerable to climate shocks and a significant contributor to greenhouse gas (GHG) emissions.
This paradox is at the heart of a new study released by the Philippine Institute for Development Studies (PIDS), which identifies two practical, scalable technologies—Alternate Wetting and Drying (AWD) and biogas systems—as key tools that could help reduce agricultural emissions by as much as 18% over the next two decades.
“Agriculture faces a dual challenge in addressing climate change,” PIDS emphasized in a press statement. “It is highly vulnerable to climate-related shocks while also contributing significantly to the country’s GHG emissions.”
The numbers are sobering. Agriculture accounts for 23% of the country’s total GHG emissions, driven largely by methane from rice paddies and livestock waste. At the same time, climate‑related disasters have inflicted an average of ₱44 billion in annual property damage from 2012 to 2022—60% of all disaster‑related losses nationwide. The sector is both a culprit and a victim, caught in a cycle of environmental degradation and climate vulnerability.
The PIDS study, Culprit and Victim: Scenarios for Philippine Agriculture amidst Climate Change, authored by Senior Research Fellow Roehlano Briones and former Supervising Research Specialist Ivory Myka Galang, explores how the sector can navigate this complex landscape. Using a computable general equilibrium model, the researchers examined three pathways: continuing current trends, strengthening adaptation, and combining adaptation with mitigation.
Their findings point to a clear conclusion: adaptation alone is not enough.
Adaptation Helps, but Emissions Rise Without Mitigation
Under the adaptation-only scenario, agricultural GHG emissions are projected to increase by 29% from 2025 to 2045. Even under the reference scenario—where current practices continue—emissions rise by 24%.
Yet adaptation does bring economic benefits. The study estimates that government spending on climate adaptation could help agricultural gross value added (GVA) grow 0.38 percentage points faster, cushioning the sector from climate shocks and improving productivity.
“This suggests that climate action can support agricultural growth while addressing the sector’s vulnerability to climate risks,” the study noted. “However, the authors observe that gains may not be distributed evenly across agricultural subsectors.”
The real breakthrough emerges when adaptation is paired with targeted mitigation measures. Under the combined scenario, agricultural emissions decline by 18%, driven largely by improved water management in rice fields and better handling of livestock waste.
AWD: Drying Rice Fields to Reduce Methane
Rice production is one of the country’s largest agricultural emitters, primarily due to methane released from continuously flooded paddies. The PIDS study highlights Alternate Wetting and Drying (AWD) as a promising solution.
Developed by the Laguna-based International Rice Research Institute (IRRI), AWD allows rice fields to undergo controlled drying before irrigation is reintroduced. Instead of keeping paddies submerged throughout the growing season, farmers let water levels drop for several days—sometimes up to ten—before reflooding.
This simple shift has profound effects.
IRRI reports that AWD can reduce methane emissions by up to 40%, while saving farmers almost one-third of irrigation water without compromising yield. It also cuts fuel and labor costs associated with pumping water.
The system relies on a basic “observation well”—a perforated bamboo or plastic tube inserted into the soil—to help farmers monitor water depth. When the water level inside the tube drops to 15 centimeters below the soil surface, it is time to irrigate again.
Across the country, farmers who have adopted AWD are already seeing tangible benefits.
In Mamburao, Oriental Mindoro, 50‑year‑old farmer Manny Valdez began using AWD in 2021. Since then, he has significantly reduced diesel expenses for his water pump and increased his harvest from 2.5 tons to 3.3 tons per hectare.
In Region 12, members of the BNBL Irrigators Association—Nestor Mendoza and Roger Celeste—attest that AWD has improved their rice production and helped them cope with water scarcity.
In Nueva Ecija, the country’s rice granary, AWD adoption is expanding rapidly, with some farmers now participating in carbon credit programs that reward emissions‑reducing practices.
AWD demonstrates that climate mitigation need not be complicated or expensive. Sometimes, it is simply a matter of managing water more intelligently.
Biogas: Turning Livestock Waste Into Clean Energy
Livestock production is another major source of agricultural emissions, particularly methane from manure. The PIDS study identifies biogas digesters as an effective mitigation tool that not only reduces emissions but also generates renewable energy.
Biogas is produced when organic waste—such as manure, food scraps, or sewage—decomposes in an oxygen‑free environment inside a sealed digester. Microorganisms break down the material through anaerobic digestion, generating a gas composed of 50–75% methane and 25–50% carbon dioxide.
This gas can be used directly for cooking and heating, converted into electricity, or refined into biomethane for vehicles. The leftover solid material becomes a nutrient‑rich organic fertilizer.
Biogas is not theoretical. It is already powering farms in the Philippines.
At Rockefeller Farm in Zamboanga del Norte, waste from over 100,000 chickens and pigs is collected in a pit dug three stories deep. According to owner Lester Uy Ong, the biogas system was built to address two persistent problems: foul odor and flies.
His wife, Heidi Ong, adds another motivation: “Our neighbors complain about the flies and the smell, and we know that in the future, electricity prices will continue to rise.”
Today, the farm operates a 300‑KVA biogas generator that supplies electricity for 15 hours a day—enough to power an entire rural barangay.
In Davao City, farmer‑scientist Felimon “Boy” Santander has been promoting biogas for more than two decades. Recognized by the Agricultural Training Institute, he has installed over 100 biogas units for small farms, households, and community bakeries, replacing LPG with clean energy derived from swine manure.
Biogas systems offer a triple win: they reduce methane emissions, improve sanitation, and lower energy costs.
A Path Toward Resilient, Low‑Emission Agriculture
The PIDS study makes one message clear: the Philippines cannot afford to treat climate adaptation and mitigation as separate tracks. They must be pursued together.
By adopting technologies like AWD and biogas, farmers can reduce emissions, improve productivity, and strengthen resilience against climate shocks. These solutions are practical, scalable, and already working in real farms across the country.
As Briones and Galang conclude, “By combining measures that help farmers withstand climate shocks with technologies that reduce emissions, the Philippines can pursue agricultural growth that is more resilient, productive, and sustainable.”
The challenge is immense, but the tools exist. What remains is the collective will to transform agriculture for a safer, more sustainable future.
