Monday, October 26, 2015

Let as save our deteriorating sloping land


Dr Abe V Rotor

Upland in Silang, Cavite, typical of farms on sloping land. Erosion does not only reduce soil fertility; it strips off the fertile "skin and flesh" of the land permanently. Here the slope has been sliced by rills and gullies, footprints of runoff water. Through years of neglect and mismanagement the land is now marginalized, a step away from becoming a wasteland.   

These are ways to conserve sloping lands. 

1. Don't disturb the natural vegetation that has preserved the state of the land, say forest or grassland, for years if not generations. Nature knows what is best in keeping the land in a state of dynamic balance, which is the key to long term stability (homeostasis).   

2. A slope does not exist as an independent piece of land - it links two terrains, the upper part is usually a watershed that catches the rain, and the lower part which deposits the net runoff in rivers, ponds and lakes. 

Destruction of the slopes leads to desertification (wasteland formation) as the land is stripped of its cover, predisposing it to repeated brush fire and erosion. Below the rivers run dry, so with the ponds, that irrigate the fields. The lake shrinks and form a swamp around it.  

3. The slopes serve as buffer and storage of water and soil nutrients.  If it is destroyed, rainwater will be lost quickly as it rushes down with little amount absorbed and kept for future use specially in summer. 

The aquifers (porous rock layers) will not be filled up to feed the streams and springs. Plants will dry up under the sun to fuel a spark into conflagration as what is has happened to many arid parts of the world - Indonesia, Australia, Green, China, and the Philippines.     

4. In the Cordillera (Mountain Province and Ifugao) terraces have been built on mountain slopes where there is a rock core, on contiguous and graded slopes that span from a cloud rich summit down to rice fields that sustain a community. Ultimately a natural waterway becomes the catchment.  The scenario starts with rain cloud from the summit slowly and continuously moving over the terraces in the shape of a giant funnel. 

Terrace building took centuries, terrace after terrace, linking the generations and cultures, unifying agriculture and ecology, and it is for these underlying reasons that the Banaue rice terraces has gained the prestige of one of the wonders of the ancient world, and today's honor as a UNESCO heritage.  

6. For privately owned sloping areas, if  one wishes to go into farming, say an orchard or woodland (agro-forestry), or as a pasture - or in combination - it is important to consult the present Land Use Policy. Consultation with the DA and DENR is important. 
Typical sloping land farming (Internet)
SALT (Sloping Land Technology) is a program of the government patterned after those of China, Nepal, North Korea, Pakistan and many other parts of the world. Author's Note: SALT  has limited applications, typically feasible on gently sloping land, and seldom in areas above 45 degrees.  Where rainfall is limited and irregular SALT is not recommended. SALT is not the answer to wasteland conversion, rather it is a wasteland prevention measure. 

7. Where agriculture is not feasible, sloping lands should be preserved as ecological sanctuary, to compensate for the shrinking natural habitats of wildlife. Ecology tourism is a boost to such areas.  More and more tourists are coming out from cities at weekend, and tourists searching for the richness of tropical greenery, the famed setting of John Milton's sequel -
I saw Paradise Lost and I Saw Paradise Regained. ~

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