Are we reDRY: The impacts and threats of El Niño on Philippine agriculture


By BENJAMIN SARONDO

The World Meteorological Organization (WMO) forecasted that the continuation of the El Niño event is 90% likely during the second half of 2023. It is predicted that it will bring at least moderate strength that will impact our health, economies, and ecosystems. 

In its context in the Philippines, El Niño is the dry season, and the climate is hotter than the average temperature. Aside from causing high temperatures and dehydration, it will trigger drought and decrease water levels in the dams and other water sources in the country, which will mainly affect the agriculture sector of the country.

Mona Liza Delos Reyes, a university researcher from the University of the Philippines Los Baños, shared her insights about the impacts and threats of El Niño on Philippine agriculture.

The two faces of El Niño

“The effects of El Niño, especially in agriculture, such as crops, livestock, poultry, and irrigation systems, will depend on the intensity or characteristic of El Niño," Delos Reyes said.

“The readily felt impact of El Niño is on the rainfall that is being reduced. Since rainfall is our ultimate source of water, if the rainfall is reduced, our water supply will also be reduced. Our irrigation system is fed with water from the rivers, lakes, and other sources of water.” 

But when rain occurs, most of the time it causes flash floods because of the lack of watersheds.

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Farm lands become drier and drier. (Photo credit to Unsplash)

She added that it can also affect the quality of the soil. The microorganisms that fertilize the soil can also be affected by El Niño. When the population of microorganisms declines, it may lead to desertification or the cracking of land.

Delos Reyes also clarified that El Niño always has a negative impact on Philippine agriculture, but she said that it can also favor the situation of the farmers depending on its duration and time of occurrence. 

“In our wet season, when our country faces a lot of typhoons, some studies have observed that El Niño helps reduce their occurrence, which is favorable to farmers and avoids the destruction of farms from heavy rain and typhoons.” 

Impacts on agriculture

“When the El Niño and the drought are prolonged and the groundwater sources are not reliable, the farmers will need to pump deep water, which will consume fuel and energy.”

“We also have rainfed agriculture, and though they are being supported by the Department of Agriculture (DA) and the National Irrigation Administration (NIA), they are still vulnerable because they do not have irrigation systems.”

“During my interview with the farmers, they always say that when there is no rain, they halt farming and just wait for the season where rain will occur,” Delos Reyes said. “Some have dug well, but they refrain from farming rice anymore because of the small amount of water, and they stick to vegetable farming that does not require a large amount of water.”

Compared to farms with irrigation systems such as dams, run of the river diversion types, or other water storage, production can continue. In some farming communities that are reliant on rainfall, they dig holes like farm ponds and take the initiative to store water. Delos Reyes said that this is usual in marginal communities.

“Plants are mainly composed of water; water insufficiency can affect their growth, and they can be stunted and their optimum growth will not be achieved if the effect of El Niño is drought.” And there are studies that show that El Niño reduced rice production, yields, and harvests by up to 30 percent. 

The farms and farmers must not depend on the irregular and uncertain rain to have a sufficient supply of water; instead, utilizing a proper irrigation system can be very helpful to secure uninterrupted agriculture.

“Our crops have different water requirements throughout their growth season, and if you want to achieve optimum crop growth, you have to deliver at the right time.”

During the wet and cold seasons, pests are high-yielding, so when El Niño occurs in this season, pests will not be harmful to the crops, and too much water on crops will also be avoided.

Threats to livestock

Crops are not the only ones vulnerable to the impact of El Niño; livestock animals are also affected. “According to the results of my field study, during El Nino, the livestock animals are dying because there is no water in the creeks,” Delos Reyes said.

She added that the grass for livestock was insufficient during El Niño because it was not able to grow because of the dry lands. This may result in the malnourishment of livestock animals or, worse, their deaths.

“Irrigation is the engine for agricultural growth.”

The main purpose of irrigation systems is to deliver water to crops and farms that are far from our natural water sources. Also, irrigation systems store water, especially those with reservoirs and storage-type dams. With the occurrence of El Niño, if you have water storage, the farms will be less vulnerable to its effects, especially the drought, and the survival rate of crops will be higher. 

We must also note that, with or without El Niño, it is favorable that our farmers store water.

The two types of irrigation systems from many are national and communal, which are gravity-type irrigation systems where the flow of water is from upland to lowland. That is why our dams are elevated. Other countries have a pressurized type of irrigation system, which is the opposite of the gravity type; the water is stored in the lowlands and pumped in pipes to the farms. 

Another irrigation system is the run of the river diversion type, where there are concrete barriers in the rivers. This irrigation system is not designed for water storage from an engineering perspective; it only blocks water to avoid oversupply to the farms. We also have an open pump irrigation system that sources water from rivers and groundwater.  

Farmers contributions

With the Philippines being an agricultural country, agriculture is the largest water user. 80 to 90 percent of water withdrawal from the environment is used in the agriculture sector. 

“The National Irrigation Administration pushes for alternate wetting and drying. Our traditional rice cultivation is flooding, where farmers flood the whole farm from the soil preparation. The alternate wetting and drying states that it is not necessary to always flood the farm area; the farmers only need to ensure that the soil is damp, and we have technology that can determine how wet the soil is, and from a practical point of view, the farmers can identify if the soil is wet.”

Alternate wetting and drying advises that farmers only need to irrigate when dry; there is no need for visible standing water. The farm gate should not always be opened to avoid overirrigation. By doing so, the farmers can conserve a large amount of water.

Also, the NIA operates a rotation system where they authorize the farmers to open and close their farm gates according to a specific schedule.

The farmers are also advised to shift to non-rice farming during the El Niño, such as vegetables, especially those in the downstream areas, that do not require a large amount of water. 

We also have methods that use modern technology, such as micro-irrigation, which uses a sprinkler or drip. They are water-saving technologies, but they are not yet feasible on our rice farm because of their cost and cannot be sustained at our present stage. 

People are also advised to start rainwater harvesting. “In Los Banos, we have a certain bracket; we have 10 cubic meters for maximum, and beyond that, the charge will be higher. This will encourage people to consume less water to pay a lower charge. 

Delos Reyes emphasized that water management should be taught to farmers and individuals outside the agriculture sector. And one of the best things to do is to establish a proper irrigation system or any other mode of watering to continuously supplement the plants, crops, and livestock. But implementing a water system requires responsibility as well, to conserve water and not contribute to water waste. 

Photo courtesy of Unsplash

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