Text and Photos by Henrylito D. Tacio
“It is more practical and economical to use management practices that minimize soil erosion rather than to allow erosion to reach the stage where restoration of eroded soil is necessary. It is essential that the productivity of these resources be maintained, especially where there is great population pressure on land resource.” — A.M. Van Oosten and E.J. Cahill, authors of Towards Integrated Soil Conservation (1986)
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Winfried Scheewe is a German national who has lived in the Philippines since 1996. An agricultural engineer, he has worked with some non-governmental organizations in the country.
He has traveled in various parts of the country and seen many farmers who are still in dire poverty. A person who loves farming, he wondered why most Filipino farmers are having trouble bringing up their standard of living.
“Agriculture is the foundation of civilization,” he wrote in his book, Nurturing the Soil, Feeding the People. “Fertile soils are rightly seen as the bedrock of civilization. (But) today’s agriculture takes soil as well as environment for granted.”
It shouldn’t be. “Soil is the basis for food, feed, fuel and fiber production, and for many critical ecological services,” said Hiroyuki Konuma, Food and Agriculture Organization (FAO) Assistant Director-General and Regional Representative for Asia and the Pacific.
“Without soil, there would be no food apart from what the rivers and the seas can provide,” said former FAO Director-General Edouard Saouma. “The soil is the world’s most precious natural resource. Yet it is not valued as it should be. Gold, oil, minerals and precious stones command prices which have led us to treat soil as mere dirt.”
Is there a solution in sight? “Seeing today’s problems in farming, we only can consider the rice terraces of the Igorot tribes in the Cordillera as a wonder,” wrote Scheewe. “The irrigated terraces provide, since hundreds of years, stable harvests of rice without external inputs. For many centuries, they had evolved cultivation methods which would maintain the fertility in an ecologically viable system. This, while soil fertility declines in many places practicing modern agriculture.”
“An ancient spatial version of the new science of agroforestry” is how Dr. Rogelio Serrano described the farming system. Having studied the Ifugao for a number of years, he co-authored with Ernesto A. Cadaweng a paper entitled, “The Ifugao Muyong: Sustaining Water, Culture and Life.”
A muyong (or pinugo in another dialect) is an untilled slope covered mainly with timber, fruit trees, climbing rattan, bamboo, palms and other associated natural vegetation, which is often used as a source of fuelwood.
“Seen from a wider perspective, the totality of the upland farming system of the Ifugao consists of the payoh (rice fields), the muyong (forest) and the uma (swidden lands). These components interact with each other, with Ifugao culture and with landscapes and ecosystems at lower elevations,” the two authors wrote.
There is a macro-level interaction between the muyong and downstream environments. “The muyong serves to capture and store rainfall and slowly releases it throughout the year, thereby irrigating the terraced payoh,” they explained. “Excess water flows through the river system… Water flowing from the muyong carries with it rich nutrients built up by the forest, which increase the fertility of the payoh. The muyong also serves as a source of rocks and stones to make walls for new terraces and to repair damaged older terrace walls.”
The second interaction is between muyong and uma. “Muyong, with its rich biodiversity, supplies seeds — dispersed by wind and wildlife — to the uma in its fallow period (ublag),” the authors wrote. “Plant regeneration is, consequently, more rapid than in the absence of muyong. The muyong also serves as a buffer to nearby uma, providing microclimates favorable to the growth of fallow vegetation, as well as trapping eroded soil.”
In Davao, the Mindanao Baptist Rural Life Center (MBRLC) has developed a counterpart of the scheme. It’s called Sloping Agricultural Land Technology (SALT). “The principle of SALT is the same as that used by the Ifugao tribes,” explains Roy C. Alimoane, the current MBRLC director. “All we are doing is suggesting using nitrogen-fixing trees and shrubs instead of rocks.”
The SALT system still requires careful management of the space between the rows of trees and shrubs. A combination of permanent, semi-permanent, and annual crops is recommended so as to rebuild the ecosystem and maximize yields while enabling farmers to organize their work time efficiently.
In the SALT farm, one finds a mix of permanent crops (cacao, coffee, banana and other fruit trees), cereals (upland rice, corn, or sorghum), and vegetables (bush sitao, winged beans, sweet pepper, tomato, eggplant, etc.). Every third strip of available land is normally devoted to permanent crops. A combination of various cereals and vegetables are planted on the remaining two strips of land. Each has its own specific area so that there can be a seasonal rotation.
“Crop rotation helps to preserve the regenerative properties of the soil and avoid the problems of infertility typical of traditional agricultural practices,” Alimoane explains on the importance of regular rotation of crops.
And yes, SALT helps control soil erosion. Its study showed that a farm tilled in the traditional manner erodes at the rate of 1,163.4 metric tons per hectare per year. In a SALT farm, there is still erosion but minimal – 20.2 metric tons per hectare per year.
The rate of soil loss in a SALT farm is 3.4 metric tons per hectare per year, which is within the tolerable range. Most soil scientists place acceptable soil loss limits for tropical countries like the Philippines within the range of 10 to 12 metric tons per hectare per year.
In comparison, the non-SALT farm has a soil loss rate of 194.3 metric tons per hectare per year.
But soil erosion is just a part of soil degradation. “Our soils are in danger because of expanding cities, deforestation, unsustainable land use and management practices, pollution, overgrazing and climate change,” said FAO in its website. “The current rate of soil degradation threatens the capacity to meet the needs of future generations.”
Aside from food production, soil can help to combat and adapt to climate change. “Healthy soils can play an important role in climate change mitigation by storing carbon (carbon sequestration) and decreasing global greenhouse gas emissions in the atmosphere,” FAO pointed out.
