By: Engr. Edgar Mana-ay
IN the People’s Republic of China and Inner Mongolia, the use of grasses rather than trees has been a success story in greening an arid land, thus halting the advance of desertification and has even better results than tree planting. Controlled grazing of a grass-covered area provides added benefit in an increased but controlled livestock industry, which of course increases meat on the table and milk for the children. In the case of Mongolia, nearly a third of its population is fully dependent on the animals they raised for food, clothing, and shelter they need.
First, we have to caution our readers that these two aforementioned places are located in a semi-arid region where it receives less rain than what we have in the Philippines being located in the tropics. Both grasses and trees have similar hydro-geology usefulness, that is: to stabilize ground surface with its roots to prevent soil erosion in cases of heavy or scant rain and for its leaves to cushion rainfall that it reaches the ground slowly to allow more penetration than over land flow. The difference, of course, is that much greater rainfall is received in our country compared to the semi-arid places in China and Mongolia.
Desertification is a process wherein barren, devoid of trees and grasses land areas are converted to dessert. This is not farfetched in our country despite the heavy rains we received considering the recent droughts due to climate change. For of what use is rain if the top soil is gone due to erosion because of lack of vegetative cover, hence the land will become barren and prone to desertification. In this case, remediation by tree planting will become an exercise in futility and grass planting is the only solution. Grasses needs a thin soil cover and definitely less water to survive and grow.
In Longbaoshan, a semi-arid farming area 65 kilometers northwest of Beijing is on the edge of desertification brought about by a combination of drought, poor land management, overpopulation, and overgrazing (sounds familiar in our place?). By planting shrubs and grasses which requires less water to survive, it has managed to halt the advance of desertification.
Between 1994 and 2000, desert lands in China grew by nearly 53,000 square kilometer, about the size of Panay and Negros. China has 20% of the world’s population but only 7% of the world’s arable land. China’s current desertification causes financial losses of $6.7 billion a year, affects the life of 400 million people, and threatens farmers and herders. China will face an unprecedented ecological and human disaster if the marching sand is not halted.
Severe sandstorms, known as Yellow Dragons, frequently turn Beijing’s sky yellow which this writer had witnessed many years ago on a stopover on the way to the U.S. via China Air. The Yellow Dragons blind residents by cutting visibility to less than 90 meters, and dump as much as 30,000 tons of sand on the city. Yellow Dragon sandstorms sometimes merge with rain clouds to inundate the city with mud.
Ten years before the 1908 Summer Olympics, Beijing used 250,000 soldiers to plant pine trees and poplars in the hope of halting desertification and cleaning the air around Beijing. Farmers and pheasants were paid grain and money if 80% of the trees they planted survived the first year. Tree-planting project in Northern China have been ongoing for 50 years, but on the whole, they have proved unsuccessful despite the communism clout.
The use of grasses rather than trees, however, has been a success story. Grass is much more effective in stopping sandstorms. Once established, it does not even have to be replanted because if protected, it just grows. Trees consume groundwater but grasses uses only rain water. The dense mat of grass roots binds the soil in place and retains moisture by inhibiting evaporation. But there is a need to control grazing from large herds of livestock because it can wreck havoc on the grasslands, compacting the ground to prevent rain from infiltrating, thus tipping the balance between plants and animals and stripping the land of vegetative cover.
In Bayinhushu, Inner Mongolia, livestock increased from about 1 million in 1940 to more than 24 million in 2000 and villagers reported more dust storms and more pastureland being lost to the dessert. Dr. Gaoming Jiang from the Chinese Academy of Sciences, worked with the villagers to reduce the size of goat and sheep herds, reserve part of their common land for grasses for animal feed and encourage the natural growth of grasses. The result? Within 5 years, the grassland was restored, the number of dust storms decreased, milk production doubled and the villager’s annual income increased from $145 to $460.
While we are more blessed in the Philippines with more rain, still there is there is a need to safeguard our forest resources like preventing the rearing of animals in the Maasin watershed for it compacts the ground resulting in less rain infiltration despite abundance of rain. Greed should be replaced by the common good for according to Mahatma Gandhi (1869-1948): There is always enough for the needy but never enough for the greedy”.
Note: The author is the Hydro-geology Consultant of the Municipality of Pavia, Iloilo.