Ever-dwindling forest cover contributes to dreaded global warming
Sri Lanka’s forest cover is estimated to be about 27% of the land area. It was three times this extent a few decades back. The Forest Department was one of the first to be established by the British and is a hundred years old. The dwindling forest cover is a constant lament among Environmentalists, Ecologists, Foresters and Wildlife enthusiasts. Forests and trees have recognized economic and aesthetic value. Bhutan is a good example, maintaining some 70-80% of the land area in natural forest, with a corresponding benefit to the “quality of life”. Generally trees are desirable and have many virtues that are the subject of this note. It is only exceptionally, such as when their roots invade building foundation or when they fall on roofs, that they cause damaging negative effects.
Sri Lanka is subject to droughts and floods that are increasing in frequency and severity and likely to do so in the future as well. There is a real fear that these multiple effects of Global Warming could have serious effects that may in the distant future, lead to the extinction of life on the Planet. Scientists have evidence to believe that this has happened in the past – as dramatized by the sudden disappearance of the Dinosaurs. The terror of extinction is so much ahead however that our generation may feel no need to worry.
Fears are real that the World may run short of fuel, water and clean air. For all these perils, forests and trees, directly or indirectly, are important influences
But, there are more immediate considerations about which we need to be aware and prepared. The fears are real that the World may run short of fuel, water and clean air. For all these perils, forests and trees, directly or indirectly, are important influences. Mercifully, Sri Lanka is outside the worst hurricane, earthquake and volcanic zones. But as a small island set in the tropical monsoon zone, we are vulnerable to localized perils and must remember the devastating tsunami of not so long ago. Further, there is a global moral obligation.
It is easy to see that “Global Warming” will impose pressures on fossil fuels, water and clean air. These long term consequences cannot be ignored – small though our overall impact might be. A few random considerations are touched.
Pressures of agriculture and urbanization have caused heavy losses of forest cover. The Mahaweli Scheme is a recent case in point. For convenience in awarding contracts and for other reasons, clearing operations have been allocated in extents much in excess of immediate needs. It would have been ecologically prudent for clearing operations to keep pace with settlement demands. Also it may well be realized in the future that the most stable system for dry zone farming, would be for areas farmed to alternate with reserves of native forests alternating with farmed land – in a “patchwork” or “strip – planting” style, with dimensions and cycles appropriately determined. Such arrangement would also create fire-gaps should there be devastating fire accidents and provide shelter for Wildlife as well.
The dwindling forest cover is a constant lament among Environmentalists, Ecologists, Foresters and Wildlife enthusiasts. Forests and trees have recognized economic and aesthetic value
FORESTS AS COMMONS
Present forestry practices treat forested areas as isolated from human trespass. Much evidence proves that this is a failure. Timber thieves and other despoilers (i.e. treasure hunters, gem prospectors, squatters, poachers and vandals) are not deterred. Much the better approach should be to enlist the co-operation of locals as joint users. This will guard against marauders and allow regulated access to timber and other forest products (firewood, fruits and medicinal herbs) .Regulated harvesting of so-called “Bush Meat”, which is anyway poached, would be possible. A sense of ownership of forest resources has many benefits. Other countries have used such approaches successfully.
DEFORESTATION AND WATER MANAGEMENT
Clearing of tree cover has spectacular damaging effects on water flow of small streams – they easily disappear. Exposed soils dry out quicker, the water table drops and wells become less productive. The ameliorative effects of trees on coolness becomes immediately apparent to anyone venturing into forest or tree reserves.
Forest tree roots open up the soil, encouraging readier infiltration of rain water. Additionally leaf fall increases water retention and slow release in the mulch. Tradition recognizes that some trees such as Kumbuk are specially valuable alongside wells. Tree roots also purify water as it moves through and may even have use in respect of CKDU by detoxification. Trees are also invaluable in controlling soil erosion or in draining swamps – often so employed in “Wood-lots” on tea estates.
Forest tree roots open up the soil, encouraging readier infiltration of rain water. Additionally leaf fall increases water retention and slow release in the mulch
A whole new discipline termed “Agroforestry” has developed. This consists of reafforesting with trees of immediate use. We have many such that could serve – the selections naturally depending on particular circumstances. Tropical Farming has a historical reliance on tree crops – often based on livelihood and market needs. The so-called “Kandyan Forest Garden” is often cited as an excellent example. The Chena system coped with depletion of soil fertility by simply moving on to fresh forests which were abundant in the past. Bhutan as mentioned, is estimated to retain 70 to 80% of their land in forest, with corresponding benefits to quality of life.
Appropriate candidates for agroforestry are very many. In addition to fuel and pulp needs, forests are in use in other tropical regions carrying a variety of timber species, Bamboos with dozens of species grown for special uses, fruits such as Jak, Breadfruit, durian, woodapple, beli, longan, Goraka etc and industrial crops such as Kapok. Opportunities are infinite each for its environmental niche.
F. H. (Sam) Popham was an adventurous retired tea planter who took it upon himself to develop a means of resuscitating degraded forest land in the dry zone. He acquired some 18 acres of degraded shrub alongside the Dambulla-Kandalama Road. He spent his entire pension and contributions from benefactor friends in the UK, to experiment on a novel concept. He observed a few vital rules, essentially based on the notion that Nature, if helped to do its job, was a far better forester than man. The usual foes were weeds, fire, stray cattle and humans. The major effort was to meticulously remove all thorny choking weeds and coarse grass. Fire gaps were established. Cattle were fenced out but wild life was afforded entry. Only privileged human visitors were permitted. He kept a careful and detailed diary of daily rainfall and water table (in his well) records. Not a single plant was introduced. Only forest tree seedlings, naturally dispersed were preserved.
The results were astonishing. The scrub progressively disappeared over the years to be replaced by a mix of indigenous trees that took on the appearance of a temperate meadow. Dried stream beds awoke to life and fish and frogs appeared. Small wild life and Jungle fowl visited every afternoon to a corner which became a “Feeding Station”.
Popham left a few years ago, bequeathing his treasure to the IFS who in turn passed it on to “Ruk Rekaganno” who it is hoped, still honour the “Popham Principles”. Although expensive a method to adopt widely, this was a classic achievement. Incidentally, Popham was a Cambridge Alumnus (Classics) and one is tempted to believe that this helped.
BIOMASS FOR ENERGY
The World is moving away from fossil fuels and moving to renewable energy forms – mainly solar, wind and biomass. In our context the last is most relevant, as the cheapest option and as rural dependence on wood fuel is very large. A good proportion of this is gathered from forests. An organized effort to grow high wood producing trees (Gliricidia initially) intends to make an impact on its use for industrial needs and for dendro-power generation.
Interesting projections for the extents of fuel-wood plantations required for generation of electricity from decentralized power stations sited close to consumption centres have suggested attractive operations. Wood requirements of such small power units, tailored to specific regional needs have been calculated. This would be a true and non-controversial “devolution of power”! The late Dr. Ray Wijewardene has to be honoured as an enterprising pioneer, who established Gliricidia as an intercrop on his coconut property, designed and built his own generator, of a size sufficient for his bungalow needs and to recharge his electric car and still provide basic power needs for his rural neighbours. Excellent PR !
Strangely, little systematic attempts have been made to support and encourage domestic solar power installations. Even heavily industrialized, Western countries are busily expanding this option. For us, this would remove a considerable drain from grid supplies, releasing the saved power for other uses. The same holds for wind power. There has been some mention of Norwegian-assisted wave-energy projects. Meanwhile, for an inscrutable reason, two large coal power stations are reportedly imminent, at a time when the rest of the World is moving away from coal or power!
MANGROVES AND SAND DUNES
Extensive mangroves grow in areas around lagoons and river mouths where the sea meets fresh water. The brackish and sheltered environments provide valuable breeding grounds for shellfish, crabs and some true fish. They are under stress due to unregulated harvesting as firewood. They protect shore-lines from erosion, and when the tsunami struck, as a protective barrier. To address the dwindling area of this precious resource, a project to replenish the exploited mangroves, a commendable project supported by a large company is in progress. The ideal component trees are fortunately quick to establish. Mangroves are vital in improving several environmental factors.
Travellers through the Hambantota area may have noticed that in recent years, a medium-sized tree, known locally as Katu Andara has colonized the sand dunes and surrounding areas, spreading rapidly. This tree (prosopis juliflora) known also as Mesquite and Tamaruga is considered an invasive species and believed to have been introduced in the 1950’s as a cover for the sand dunes in this arid area. This it has done well but proved to be highly invasive and has spread well beyond its original area. It has limited uses - of the pods and seeds as a minor food, for medicinal uses and the young foliage as fodder for roaming cattle. Its bark may well be of use for tanning leather. Its sudden spread is probably due to cattle feeding on it and passing the seeds out with their dung. Although useful as firewood, its thorny nature is a disadvantage. It burns fiercely and thus could find use for dendro-power. Due to its thorny nature, it would require mechanized harvesting (tractors) to meet handling problems. Its rapid growth is an advantage. It could even prove to be a pioneer species to enable planting these otherwise barren wastes with useful tree crops (like Cashew) once “softened” by this tree. One remembers how the barren wastes of the dry patanas, widely regarded as inhospitable for use, were transformed by planting with Gums (eucalyptus). This in turn elevated Palugama to the township of Keppetipola. This was more than a mere change of name !. One is aware that widespread monoculture plantings (in our case, pinus) are controversial for ecological reasons. The original intent ion to use these plantation as a source of pulp for paper is yet to become a reality.
PRESERVING ENDEMICS AND THE GENEPOOL
Our country is highly blessed with a wealth of endemic and sometimes unique, plants and animals. It is classified as a “Biodiversity Hotspot” by UNESCO. This floral and faunal variety has to be preserved, not least because it could be a massive asset, for breeding, search for novel products such as herbal pharmaceuticals and as a tourist attraction. Bio-piracy is of huge international concern. Much of our endemic flora grows in the Low Country Wet Zone, in which the Sinharaja represents the only sizeable remnant. Encroachments by tea plantings and poorly located mini-hydropower plants need to be controlled. The recent frequency of detections by Customs of attempts to smuggle out Wallapatta (Agar Wood) suggests widespread despoiling of protected reserves – possibly before the very eyes of policing authorities. As is well known, a large percentage of Medicines are of plant origin, and much probably are still in the forests awaiting discovery.
UNECONOMIC TEA LANDS
There exist considerable extents of abandoned or uneconomic tea lands. These should be earmarked for other uses.The soils have been so impoverished that few substitute species will thrive. One immediate approach may be to allow such tea bushes as have survived in such areas to remain and grow into trees, to be a nucleus allowing forest trees to establish. Once some fertility is thereby regained, more profitable cultivations could succeed. Illegal cultivations above the legally prescribed contours should be compulsorily and forthwith abandoned for reversal into Montane Forest. The Central Highlands need protection as the principal source which nourish our rivers.
The World’s recognition of increased atmospheric carbon dioxide as an important cause of Global Warming has established a scheme of “Carbon Credits”. This is calculated based on actions taken to reduce carbon dioxide emissions to the atmosphere. A globally accepted scheme exists for awarding “Carbon Credits” that could be traded with countries which were requiring over agreed quota. Thrifty countries are awarded credits for carbon sequestration which they could sell or barter with excess emitters. The “currencies” were valued at one Unit per ton of carbon dioxide. Recognizing that developed countries were the larger emitters (through industry, vehicles, and domestic consumption etc) they were obliged to make greater reductions (at 25% of figures, with 1990 as the base year, with developing countries assigned lower percentages and other concessions to meet their targets). The scheme operates similar to the Stock Market. Each country farms out its allocation, to its high emission companies. Any company operating within its allocation could trade its savings on the stock market, for trading with those releasing above quota. The latter are required to pay a tax or purchase the deficit from the market.
While it is relatively easy to calculate emissions, from industry and power installations, the interplay of many variables make the task more difficult for sequestration by forest trees. As a result, while emission figures were set out relatively easily for industrial emissions, those for trapping in forest trees have led to many difficulties of implementation because of the complexity of several variables. .
Amidst all the complications, an important consideration is that trapped carbon in trees is offset by releases through decay or burning of fallen leaves and branches and eventually as timber. The locking up of carbon is thus temporary.
These various issues merit the closest attention by our competent professionals.