By Ranil Senanayake –
One of the observations that with climate change comes an increase in peak weather events, became a horrible reality to us last week. Our mountains, bearing soil on a rocky base, was once stabilized by the unbroken blanket of forests that covered it have become destabilized. The tragedy of the loss of life at Meeriyabedda is a warning, we have to change the way in which we treat our soils and landscapes.
The erosion of our soils and the loss of both soil nutrients and biodiversity have forced us into the current chemical basis of agricultural production. The chemical methods of agriculture do not build up populations of soil bacteria, soil bacteria that produce the polysaccharide gum that binds soil particles and soil without good structure quickly dissolves when wet.
But we are proud of a chemically maintained monoculture over our mountains, a monoculture that precludes the use of trees, a monoculture that does not lend stability to the soil. This is our tea country.
Soil, is one of the most important components of any land, yet its value has been overlooked by most modern approaches to land development, agriculture and forestry. To most of us, soil is the stuff that holds trees up. We see it as a solid surface for us to walk, ride or construct upon. Our perception of its usefulness in our daily lives does not exceed much beyond providing a medium to grow our crops. In fact modern agriculture has discounted the value of soil in providing nutrients for plants by promoting the role of artificial fertilizer to the detriment of good soil management. In Sri Lanka most texts on soil only address the physical or chemical nature of soil, a view that has allowed our farmers to be pushed into reliance on ‘high input chemical agriculture’, by the multinational chemical companies.
Soil is a dynamic ecosystem, one gram of ordinary farmyard soil can contain over 1 billion individual bacteria, over 100 million individual actinomycetes and over 1 kilometre of fungal hyphpae, notwithstanding plants like algae and animals like collembolans, nematodes or worms. This massive diversity provides for the multitude of critical functions, that a living soil provides.
When soil looses its tree cover and the input of organic matter to feed the living soil, its biomass goes down, it looses its cohesive strength. The loss of cohesive strength accelerates the erosive processes, that was once held in check by soil binding agents, both macroscopically and microscopically created. The macroscopic binding agents are the roots of plants and plant compounds. The microscopic agents are the bacterial gums, polysaccharides and humates. With an increase of chemical reliant intensive farming there is a corresponding loss of soil microorganisms that provide cohesive strength to soils. The result is, erosion in wet weather and an increase of dust during dry weather.
Having weakened our soils through irresponsible agricultural practices and loss of forest cover, we have now turned our attention to the rock base that these soils lie on. The rocks in much of the mountain areas are now being blown up (quarried) for ‘development’ purposes. The resulting vibrations and shockwaves further weakening the integrity of the soil mass that lies above the rockbase. When blasting, the energy from a blast, which is not used for rock breakage, is radiated outwards in the form of ground vibration and airblast. Seismic waves spread out from the blasthole, along and through the ground, much like ripples in a pond. Ground vibration is comprised of many different waves with different frequencies and travel paths. These components (frequency, displacement, peak particle velocity, and acceleration) are measured with a seismometer. For instance, Peak Particle Velocity (PPV) is a measurement of the maximum speed (measured in mm/sec or in/sec) at which a particle in the ground is moving relative to its inactive state and is a most predictable indicator of possible damage. Has this been measured for the overburden of soil when giving out licenses for rock quarries?
The experience in Sri Lanka is that rock blasting is a manipulative process, whereby even the decision by the District Secretary on the basis of examination, is surreptitiously overturned as soon as he/she is transferred. A case at point are the quarries at Mirahawatte in Bandarawela, the villages fought against the blasting of a quarry for years and finally had the blasting stopped; But two years later, as soon as the DS who had inquired into the process was transferred, the permits for blasting was issued again, in a total snub of the rights, concerns and danger to the villagers.
In the face of climate change, when the incidences of extreme weather events are becoming more frequent, there will be more and more of such events. But we seem hell bent on increasing these disasters. While it is common knowledge that the addition of Carbon Dioxide into the atmosphere increases the impact of climate change, we in Sri Lanka have chosen to contribute increases huge volumes of this gas as a product of the current vision of ‘Development’. Climate irresponsible actions such as, coal and oil fired power plants, energy expensive transport on roads, massive concrete construction where I kg of concrete produces 16 times the CO2 equivalent as oil, are the hallmarks of the current regime.
Will we ever have a holistic vision of this nation and the concern for the long-term management thinking that is required to ensure a benign future for our children and us ? Moving people from point to point after a crisis strikes will not cure anything. The solution is simple; invest in HEALING OUR LAND as the national development priority. Make this land more safe for us to live on, not more dangerous ! Otherwise any statement on the concern for our land and our well being will ring hollow.