Inter Press Service
Monday 03 December 2007
Brooklin, Canada - Expanding European forests absorbed 126 million tonnes of carbon dioxide from 1990 to 2005 - equivalent to 11 percent of European Union emissions from human activities - while a U.N. target to plant one billion trees mainly in Africa has been surpassed.
"Forests reduced carbon dioxide more than twice the amount of Europe's renewable energy programmes," said Pekka Kauppi, who led the University of Helsinki study, published in the British journal Energy Policy on Nov. 29.
Better conservation, migration to cities, and conversion of surplus farmland are the reasons behind the growing and expanding forests, which are mainly in Latvia, Lithuania, Sweden, Slovenia, Bulgaria and Finland Kauppi, told IPS. The study is based on forestry statistics provided by governments and that were not independently verified.
The resulting "surprisingly high carbon dioxide removal" may be the major factor in Europe achieving its ambitious target of 20 percent reductions in greenhouse targets by 2020, Kauppi said.
"On a global scale, there is hope for the future if we stop deforestation and expand forests," he added.
For that reason, carbon credits should be given to standing forests, which would offer countries and forest owners additional financial incentives for conservation, he said.
However, there is intense disagreement on this issue.
"Forests are a band-aid," said Mike Flannigan, a research scientists at the Canadian Forest Service. "Eventually, forests die, releasing all that stored carbon into the atmosphere."
"Forests are carbon-neutral over the long term," Flannigan told IPS.
Growing forests can be "carbon sinks", soaking up additional carbon from the atmosphere for 60 or more years until they reach maturity. But no one knows how long a tree planted today will live. Weather, disease, fires and other factors can shorten the life of any tree.
Illustrating the complex factors involved, one day after Kauppi's study was released, researchers at Wageningen University in the Netherlands reported that a drop in atmospheric nitrogen deposition will slow down forest growth, resulting in 27 percent less carbon sequestration (removal) than current levels. Pollution control measures are reducing nitrogen emissions to improve air quality. Trees need nitrogen and carbon to grow.
Canada's forests have become enormous sources of CO2, mainly due to the rapid spread of an insect pest called the mountain pine beetle and record-breaking fires in recent years. Both the fires and the beetle infestation appear to be consequences of climate change itself, warming and drying forests in western Canada.
"Higher surface temperatures dramatically increase evaporation rates, leaving forests tinder dry," Flannigan said.
Canada is now losing several million hectares every year to fire, as is Russia and to a lesser extent Alaska. The same mechanism is behind Australia's major increase in brush fires, according to research published in 2006 in the U.S. journal Global and Planetary Change.
Forests and their peat soils in the remote Boreal region hold about one-third of Earth's stored carbon and are the ticking "carbon bomb". Peatlands have been absorbing CO2 for thousands of years and if they dry out and substantial areas begin to burn, cataclysmic climate change is virtually guaranteed.
As global temperatures rise, peatlands will dry out, making it imperative to reduce CO2 emissions from burning fossil fuels, Flannigan said.
"Forests as carbon sinks is a distraction from the real problem of cutting emissions," he noted.
Forests should be protected and replanted for their ability to clean and store water, generate oxygen, cool cities and provide habitat and biodiversity, he said.
Fortunately, those benefits accrue no matter why trees are planted. And the world has at least a billion new trees thanks to the U.N.-sponsored Billion Tree Campaign. Launched only a year ago, it has led to huge forestry projects in Ethiopia and Mexico, the U.N. Environment Programme (UNEP) reported last week.
Ethiopia appeared to be the runaway leader, with 700 million trees planted in a national reforestation drive. Only three percent of Ethiopia is now forested, down from 40 percent centuries ago. Guatemala, China and Spain will shortly announce that several million more trees have been planted. And Indonesia was expected to plant almost 80 million trees in the run-up to the high-level Bali climate conference, which opened Monday.
UNEP says that half of the trees were planted by private citizens, but acknowledges it does not verify planting pledges.
"I am elated beyond words at the global interest and action that was motivated by the Billion Tree Campaign," said Nobel Peace Prize winner Wangari Maathai, founder of the Kenyan Green Belt Movement and a chief architect of the campaign.
"I knew we had it within us as a human family to rise up! ... Now we must keep the pressure on and continue the good work for the planet," Maathai said in a statement.
A Dirty Way to Fight Climate Change
By Steven I. Apfelbaum and John Kimble
The Christian Science Monitor
Thursday 29 November 2007
A promising strategy: Store carbon in the soil.
Brodhead, Wisconsin and Lincoln, Nebraska - Switch to compact fluorescent light bulbs and plant a tree - these are the most popular strategies for mitigating climate change today.
Yet world leaders gathering for the climate-change summit in Bali, Indonesia, next week should consider an alternative. It's one of the most overlooked yet most effective and inexpensive strategies available: Store carbon in the soil.
This is one way the earth has managed carbon since it began. The earth's soil contains the second-largest quantity of carbon, where it has been the most stable and least vulnerable to fires and climate changes. (The largest amount is dissolved in oceans.)
Planting trees sounds like a flawless solution: Trees absorb carbon, after all. But it can actually be quite harmful, even dangerous. Soil needs "riches" such as carbon, organic matter, and mineral nutrients, and they come in part from the "litter" left by plants that grow and die annually on the land. By planting trees in soils that were created by other, more productive plants (e.g., prairie and wetland plants that used to occupy some of today's farmland), less litter is produced. That means less carbon and organic matter are contributed to the soil, causing it to deteriorate.
In some areas, planted trees can dewater the soil. They can also release nitrogen and phosphorous in runoff that enters rivers, lakes, and estuaries and hurts water quality. More worrisome, some forested areas are becoming more vulnerable to wildfires, because changing precipitation patterns and the associated drying effects are creating a tinderbox. These changes appear to be resulting in bigger and more frequent fires (e.g., very recently in California).
Ecological lesson No. 1 is that we should plant trees only where the soils will benefit from it.
The corollary, lesson No. 2, is not to plant trees where inappropriate, for example, in farmland that used to be wetlands and grasslands. Native, deep-rooted plants should be grown in those areas instead, since they enrich the soil - with carbon, among other things - more quickly.
Lesson No. 3 is that, in the face of drought and increased wildfires, rebuilding soils is a safer strategy for storing carbon.
There are two ways to do this. First, restore conservation lands - which are not used for farming - with deep-rooted grassland or wetland plants, which sequester carbon more effectively than trees do. Second, rebuild America's soil systems in farmland, where the soil's riches have been depleted by intensive growing of crops. Few farmers are going to give up their livelihood to fill their land with grassland and wetland plants. But they can still help increase carbon soil through techniques such as "no-till" farming, in which farm-seeding equipment inserts crop seeds into slits cut into the soil. Tillage farming, by contrast, involves plowing and disrupting the soil, which releases carbon.
Scientific analyses show that recapturing atmospheric carbon into soil and plant communities is the easiest and least expensive method for mitigating climate change and that it provides many other economic, cultural, and ecological benefits. Restoring soils in currently farmed land can rein in 10 to 15 percent of the annual carbon emissions Americans create. Replanting native grasslands and restoring drained wetlands can reduce up to another 20 percent.
These techniques can also produce usable bioenergy crops, food, and fiber supplies. This enables energy, food, and commodities to be produced locally, thus reducing transportation and distribution costs and their associated carbon emissions.
Farmers have reported that no-till agricultural practices delivered savings in just 2 to 3 years and increased crop yields by 10 percent. It also reduced fossil-fuel use for farm machinery by 90 percent.
Because it leaves leftover plant matter on the land, no-till agriculture could add 1.3 inches of soil materials and organic matter per acre over the next 50 years. The many feet of new soil would be a sponge to hold back runoff and nutrients from entering rivers and lakes and hurting potable water supplies. It would also help reduce costly, damaging floods.
We need to follow nature's lead and put carbon where the earth has securely stored it for millions of years - in the soils. Among many other benefits, this will cleanse the atmosphere, taking a big bite out of the existing greenhouse-gas loads.
-------
No comments:
Post a Comment