Vol. XXVI, 1st Quarter
Philippine crop and farm animal production may decline if the current dry spell continues. Previous major drought events affected agriculture productivity badly.
Drought episodes in 1982-83, 1991-92, and 1997-98 resulted to production losses in rice and corn. Estimated loss in rice production was 648,480 tons in 1982-83, 669,000 tons in 1991-92, and 622,000 tons in 1997-98.
The value of corn production loss was 65% higher than that of rice in 1997-98, and more than three times higher than in 1991-92. Losses for rice and corn alone amounted to more than P12 billion in 1997-98.
These were the findings of an impact assessment study conducted in 1999 by the Philippine Council for Agriculture, Forestry, and Natural Resources Research and Development, an agency under the Department of Science and Technology. The assessment covered rice and corn-growing areas in 30 barangays in nine regions of the country.
The study also assessed the effects on livestock and poultry production during the drought in 1997-1998. Heat stroke and avian pest ravaged the poultry industry and trimmed average poultry population in the barangays [villages] down by 67 percent. Figures from commercial farms were excluded.
Swine population in the barangays shrunk by 79 percent while goat population dwindled by 45 percent. Growers were forced to sell the animals and to compensate for the losses from rice and corn farming.
Farmers also ran out of options and had to sell their cattle because of scarce water and grazing areas. Cattle grew thinner slashing their market value.
The Department of Agriculture, on the other hand, reported that the 1997-1998 drought affected almost 74,000 hectares of agricultural lands in 18 provinces. It wrought damages to farmlands devoted to rice, corn, sugarcane, coconut, and banana plantations.
During the first half of 1998, the country’s palay production went down by 27 percent, and corn production suffered 44 percent drop.
Livestock especially in Negros Occidental suffered heat strokes, pneumonia, stress, and dehydration. A vast 7, 628 hectares of sugarlands in the province were declared unfit for production setting off widespread hunger among the farming folks. Damages to crops in Negros Occidental alone were estimated to have cost P99.7 million, and to livestock at P425, 700.
Newspaper accounts showed that in Northern Mindanao, more than 74 people died and about 497,238 agricultural families including tribal communities starved because of drought. Manufacturing and agricultural exports in Southern Mindanao declined and led to labor cutbacks in plantations engaged in these businesses.
The dry spell in Davao del Sur, North Cotabato, and the hinterlands of Davao City triggered high incidence of drought-induced diseases and pests. Rats infested the region’s farms planted to rice, corn, banana, cacao, mango, sweet potato, and cassava. Malaysian black bug raided rice fields in Saranggani, South Cotabato, Davao City, and Davao del Sur.
Moreover, forest fires ruined portions of Mt. Apo, Mt. Matumtum, and forested areas in Maragusan.
Preparing for drought
Drought inflicted damage in the past need not happen again. PCARRD recommends early and efficient warning or extensive information dissemination on changes in weather conditions that are likely to affect farming communities. On a per area basis, agricultural technicians should advise farmers on changes in cropping patterns, timing of planting, and mitigating measures.
Crops that can withstand long dry spell are okra, mungbean, pole sitao, and cassava. However, appropriate planting schedule should be observed to ensure moisture availability during crop growth. Effective practices that can reduce water loss are leaf pruning, and use of coconut-husk- based materials to condition the soil.
Dry seeds instead of transplanted seedlings can be used in rainfed upland and lowland rice areas growing a single rice crop. This saves time and uses rainwater more efficiently for crop growth. Pre-germinated seeds may also be used in rainfed lowland rice areas.
The country has a high average rainfall of 2,000 millimeters per year. Yet, a few rainless months hamper agricultural activities. To take advantage of existing rainfall and runoff, water conservation measures should be implemented.
The small farm reservoir or SFR is an earth dam structure, which stores rainfall and runoff during heavy rains that can be used during lean months. Temporary dikes and micro catchments could be used to delay runoff in upland farms and increase rain infiltration.
Available soil moisture can also be conserved in several ways. By spreading plant residues or synthetic materials as mulches, moisture loss due to evaporation can be prevented. Applying compost fertilizers improves soil structure and increases water-holding capacity.
Available irrigation water could also be conserved by placing windbreaks or shelterbelts composed of trees, shrubs, and vines planted at the farm boundaries. A combination of large and small windbreaks arranged systematically can significantly reduce water loss caused by evapo-transpiration.
For those willing to invest additional resources, installing pipe irrigation systems could reduce evaporation, percolation, and seepage to almost zero. Using plastic pipe channels instead of open canals could help irrigate wider areas with the same amount of available water.
Artificial insemination can be used as an alternative to natural breeding of animals because their reproductive performance tends to decrease during prolonged hot and humid months.
Non-conventional energy sources for animal feeds and locally available energy feedstuffs such as arrowroot, banana, camote, and cassava can be used to replace corn. In areas where forages and agricultural left overs like grasses and other plants are plenty during wet season, it is best to prepare silage, a fermented ruminant feed, for consumption during dry periods.
To prevent heat stress, animal pens and housings should have appropriate ventilation and cool clear water should be provided.
Still the best way to mitigate the effects of extreme drought in forestry is to restore forest cover through tree planting. Forest cover raises the water shortage capacity of watersheds and minimizes silting of reservoirs.
Drought resistant tree species such as akleng parang, alibangbang, binayuyu, ipil-ipil, kamachile, and katurai survive moisture stress during water-deficient periods with little or no injury. Bamboos and other forest and fruit trees can withstand extreme heat conditions, too.
[Details on each specific technology interventions can be found in PCARRD and DA’s published book on ENSO Mitigating Measures. For more information, PCARRD can be reached at tel. No. (049) 536-0014 or e-mail email@example.com.]