Forest fire emissions ‘poisoning Arctic environment’


Forest fires and straw and stubble burning in North America and Eastern Europe are leading to record-high concentrations of the environmental toxin PCB over the Arctic island of Svalbard, a report warns.

Take Cover library imageOver the past decades, persistent organic pollutants (POPs) have been found in large concentrations in Arctic areas.

These substances accumulate in living organisms and are enriched throughout the food chain.

Polychlorinated biphenyl (PCB) is one of the most important environmental toxins of this type.

“We wanted to draw attention to the causes of the environmental impact in the Arctic and trace the sources of the problem,” said Sabine Eckhardt, a researcher at the Norwegian Institute for Air Research (NILU).

When biomass from trees and dead grass and leaves catches fire, it releases both PCB and other environmental toxins and creates yet another source of PCB emissions.

In 2004 and 2006, big fires ravaged these areas. About 5.8m hectares of coniferous forest burned down in North America, while Eastern Europe experienced extensive emissions from agriculture due to straw and stubble burning.

Several weeks later, the researchers found record-high values of PCB in the atmosphere above Svalbard.

“As far as we know, this is the first study that shows a connection between the burning of biomass and PCB concentrations in the atmosphere far away,” said Sabine Eckhardt.

“With a climate that is constantly changing, we expect the extent of such fires to increase.

“In such case, it also means that the fires may represent an increasing environmental problem in the Arctic.

“That in turn will reduce the effect of the international agreements that aim to reduce emissions of these environmental toxins,’ said Ms Eckhardt.

PCB is a group of synthetically-produced persistent toxic compounds., and can be stored in the fatty parts of the organism and accumulates in the food chain.

Humans, fatty fish and carnivores (such as polar bears) can therefore accumulate concentrations in their bodies that are so high that they are poisoned.

As the primary emissions of organic environmental toxins are reduced, the researchers believe that fires caused by climate change will become more important.

They point to the fact that there has been little focus on the significance of burning biomass, and the potential consequences of this for the Arctic environment.

“For the first time, we have proved that burning biomass is also an important source of persistent organic pollutants in polar areas,” Ms Eckhardt observed.

“This can be of great importance to international agreements that aim to protect the environment in Arctic areas.”

Source: The Research Council of Norway

Date: 31/05/2010

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Twiglet: UK woodlands and forests


The social and environmental value of woodlands and forests in the UK is estimated to be in the region of £1bn, states a postnote from the UK Parliamentary Office of Science and Technology.

Once, most of the UK was covered in woodland but the cover was gradually depleted as the demand for timber, fuel and agriculture grew.

By the beginning of the 20th Century, woodlands made up about 5% of the mainland.

Following the sharp increase in demand for wood products during World War One, the government established the Forest Commission. Its aim was to build a strategic timber reserve.

This was achieved by a large scale planting programme, mainly involving non-native conifers, such as North America’s Sitka Spruce (Picea sitchensis). The plantations were established on marginal agricultural land.

Overall, the UK has quite a diverse wooded landscape; the majority of the native trees are broadleaves. The nation has three native conifers: Scots pine, yew and juniper.

Woodland is considered “semi-natural” if it is composed of locally native species. A small proportion of the remaining woodlands are considered “ancient”, because their origins can be traced back to before 1600AD.

In recent years, a growing awareness for the need to conserve certain habitats and biodiversity has led to a shift in management practices.

From the primary concern being the production of timber, the focus is now on “sustainable forest management”.

This aims to provide social and environmental goods while maintaining an economically viable forest, protecting it for future generations.

The forestry and timber industry is estimated to contribute £7.2bn a year to the UK economy.

It produces nine billion cubic metres of wood products annually, however this is still less that a fifth (18% in 2007) of the total wood products used in the UK each year.

Most wood in imported. The majority of the imports come from Europe, however a sizeable minority comes from further afield.

Campaigners have identified that some of this wood is harvested from old-growth tropical forests, resulting in the loss of valuable habitat and biodiversity.

Looking more detail at the environmental value of a woodland or forrest, a number of “ecosystem services” can be identified, including:

  • protecting soil from erosion
  • reducing flooding in some catchment areas by intercepting rainwater and reducing run-off in stormy weather
  • helping reclaim contaminated land
  • proving shelter, shade and cooling in urban areas, and wind shelters on farmland
  • conserving biodiversity (broadleaved woodlands contain more than twice the number of rare species, according to the UK BAP, than any other habitat
  • conifer plantations also have role to play in conserving rare species, because they offer protection to species like the red squirrel and the capercaille.

Looking at the role of the UK forest and woodland cover in carbon sequestration, it is probably safest to state that it does have a role to play in mitigating the impacts, but it can never replace a broad strategic effort to decarbonise the UK’s economy and activities.

The UK has adopted a number of international forestry agreements – it was a signatory of the Statement for Forest Principles at the Rio summit in 1992. It also agreed to the general declaration on the Protection of Forests in Europe, which was presented at the 1993 European Ministerial Conference in Helsinki, Finland.

These agreements basically enshrine sustainable forestry measures into a policy framework. Hard to believe, but the European Union has no direct jurisdiction over forestry policy. Instead it is formulated at a member state level.

But there are some EU legislation that has an influence on forestry matters. These include CAP, EU Habitats and Species Directive, Environmental Impact Assessments, and the Water Framework Directive.

Within the UK, forest policy has been devolved to the national administrations. Policy in Scotland and Wales is decided by the national Forestry Commissions on behalf of the national political executives.

Since the widespread adaption of conifer plantations in the UK, most are same-age stands, which are felled in large areas in one go.

This is considered to limit or damage the social and environmental value of the plantations and local habitat, so there are plans to consider alternative management techniques, including:

  • Continuous Cover Forestry – smaller areas are felled in one go, allowing the overall habitat to remain largely undisturbed, and also allowing a mixed-age stand to develop)
  • PAWS restoration – some conifer plantations were created on ancient broadleaved woodlands, so there is a growing commitment to restore “PAWS” (Plantation on Ancient Woodland Sites)

Even though there is increased protection measures for semi-natural and ancient woodlands (such as SSSIs etc), their wildlife could still be under threat as a result of human activities. Recent surveys show that many woodland species have declined dramatically since the 1970s. One theory for this worrying trend is because it is the result of changes in the structure of the woodlands, stemming from the lack of management.

Threats to the woodland and the species within them include:

  • increasing fragmentation: small patches of woodland, isolated by other land use changes, are more vulnerable to change and can support fewer species
  • decline in woodland management: over the past century, active management of woodlands for timber has declined. This has led to a reduction in open areas within woodlands, on which many species depend, contributing to a decrease in biodiversity.
  • Overgrazing: Increasing deer numbers (including four introduced species) are an issue across the UK. Deer are a part of the woodland ecosystem, but overgrazing affects tree seedlings, ground flora and other wildlife. In upland areas, sheep can also cause overgrazing.
  • Pollution (and other external influences): the threat from acid rain has decreased over the years as the result of tighter emission controls of coal-fired power stations. However, localised air pollution can still be a problem. Fertiliser and pesticide drift from adjacent farmland is an issue on woodland edges.
  • Invasive species: some non-native species (such as rhododendron and grey squirrels) pose threats to woodland ecosystems by damaging or out-competing native species.
  • impact from recreational users: trampling can have a locally significant impact on woodland ground flora. Disturbance by humans and dogs may also affect other wildlife, such as breeding birds.

The future of woodlands is ultimately at the mercy of climate change. Changes are already being observed within the woods in the UK, Oak buds are opening up to two weeks earlier than what they were in the 1950s, probably as a result of warming temperatures.

There is one school of thought that suggests that increased levels of CO2 in the atmosphere will lead to plants and trees increase the rate at which they convert the gas and nutrients, leading to an increased growth rate.

However, other factors need to be taken into account, such as changes to precipitation or water tables.

All projections and models have a degree of uncertainty within them, so there is not a clear picture of how the nation’s woodlands will look in the future. The only certainty is that they are not going to remain static and change is occurring.

Source: UK Parliamentary Office of Science and Technology (Post)

Date: 02/02/2009 (however the postnote was first published in 2007)

Ranching ‘biggest driver of deforestation’ in Brazil


Cattle ranching is the biggest driver of deforestation in Brazil, says Greenpeace.

In evidence presented at the World Social Forum, hosted by Belem in the heart of the Amazon, the environmental group said it showed that cattle ranching was the biggest driver of Amazon deforestation.

Greenpeace Brazil has produced a series of maps which it said showed the links between cattle ranching and tree felling in the highest resolution to date.

The details have been released as part of the organisation’s Save the Planet – Now tour.

Greenpeace lists the South America nation as the world’s fourth biggest polluter, with 75% of its emissions stemming from deforestation.

The Brazilian government has pledged to tackle destruction of the Amazon as part of its climate commitments. However, green campaigners say plans to expand its cattle industry contradict these.

Internationally, tropical deforestation is responsible for a fifth of global greenhouse gas emissions, more than the global transport sector.

Source: Greenpeace International

Date: 29/01/2009

High coffee prices ‘triggers Indonesian deforestation’


High coffee prices were responsible for a marked increase in deforestation on the Indonesian island of Sumatra, say researchers in a report in Mongabay.com.

But they added that law enforcement efforts could deter deforestation in protected areas, despite high pressure from agricultural expansion.

The study was assessing the effectiveness of conservation in Bukit Barisan Selatan National Park in southern Sumatra.

Using satellite imagery, ecological data, interviews, and GIS modelling to map tropical deforestation in and around Bukit Barisan Selatan over a 34-year period, lead author David Gaveau and colleagues found that law enforcement effectively “reduced deforestation to nil” in areas where it was undertaken.

In remote parts of the park where enforcement activities were lax or non-existent, forest areas were rapidly replaced by low-grade robusta coffee plantations, expansion of which was found to be closely correlated with coffee prices.

An estimated 20,000 tonnes – about 4% of Indonesia’s overall annual robusta coffee production – were produced inside this national park in 2006, and were exported into 52 countries around the world, reported the WWF in 2007.

The abandonment of the park by authorities during, and following, the 1997-1998 political crisis also resulted in increased deforestation.

“These findings indicate that law enforcement is critical but insufficient alone, and also highlight that rising costs of agricultural commodities can be detrimental to tropical forests,” said Dr Gaveau, a researcher with the Durrell Institute of Conservation and Ecology and the Wildlife Conservation Society’s Indonesia Programme.

“In southern Sumatra, farmers grow coffee instead of working elsewhere (e.g. in the off-farm sector) because rural labour is poorly compensated (around $2 per day).

“Therefore, higher local prices for coffee combined with low labour costs, rather than coffee price per se, is the underlying cause of deforestation in Indonesia’s main robusta coffee producing region.”

The authors argue that preserving forests in Bukit Barisan Selatan over the long-run will require a strategy that reduces the incentives for coffee cultivation.

They discuss merits of certification schemes for “sustainable” coffee as well as intensification of production, but conclude that raising rural wages relative to coffee prices, in concert with other measures, offers the best long-term hope for curtailing conversion for coffee in the Bukit Barisan Selatan area.

Source: Mongabay.com

Date: 22/01/2009

Disagreement over rainforest recovery


Will rainforests survive? That was the topic of a debate at the Smithsonian Institution’s National Museum of Natural History.

Satellite data and other research has revealed that huge tracts of abandoned tropical forests, which were once logged or farmed, are regrowing.

This evidence has prompted a contentious exchange of views and theories among scientists around the world.

One camp suggests that the regrowth of rainforests has been overlooked, resulting in the current “biodiversity crisis” argument, which fears that half of the world’s species could be lost in the coming decades, is too pesimistic.

However, another school of thought contends that only about half of the plants species originally found in rainforests will return to the areas, and that many animals will not survive the transition.

Others warn that the continuing expansion of netoworks of access roads into rainforests will make it easier for poachers and loggers, threatening the existence of tropical species even further.

Cristian Samper, director of the National Museum of Natural History, who presided over the debate, said: “By bringing together the world’s most foremost authorities on different aspects of rainforest sicence, we hope to achieve new insights into a situation with potentially profound implications for all species, including ours.”

Using a combination of satellite data and field research, estimates suggest that:

  • ten million square kilometres have been cleared of at least half of their wood cover for human uses, includingtimber and agriculture
  • five million square kilometres have been selectively logged, often with high-impact methods that leave forests degraded
  • Of the intact forests remaining, about 275,000 square kilometres – an area bigger than the UK – were felled in five years (between 2000 and 2005)
  • approximately 350,000 square kilometres  (about 2% of original forested areas) are in some stage of regrowth, primarily in South Asia and Latin America.

According to Greg Asner from the Carnegie Institution, deforestation was the most profound change underway in tropical rainforests.

However, he added, land abandonment was the second most important trend, with the majority of the abandonment occurring in upland areas that offered marginal farming opportunities.

Often, the inhabitants departed to pursue better income opportunities in lowlands and cities.

He added that regrowth was relatively quick:  the forest canopy closed after just 15 years; after 20 years, about half of the original biomass weight had grown back.

Joseph Wright, from the Smithsonian Tropical Research Institute, noted that more than 20% of all land within 10 degrees of the equator had acquired protected status, and that the tropics had a percentage of protected land greater than North America, Europe or Japan.

He and colleague Helene Muller-Landau asserted in a 2006 study: “Large areas of tropical forest cover will remain in 2030 and beyond.

“We believe that the area covered by tropical forest will never fall to the exceedingly low levels that are often predicted.”

They added: “Extinction will threaten a smaller proportion of tropical forest species than previously predicted.”

Their position was partly based on UN predictions of growing urbanisation and slower population growth.  As a result, the abandoned areas will recover and tropical species spared, they contend.

But William Laurance, also from the Smithsonian Tropical Research Institute, argued that secondary and degraded forests would sustain only a fraction of existing animal species.

He added that birds and mammals were more vulnerable to the altered habitat than insects and other small organisms.

Forest destruction in years past was largely the result of land being cleared for small-scale farming, he observed.

However, trade globalisation was fostering large-scale industrial agriculture, logging and mining; all of which was accelerating forest destruction.

The world was now losing the equivalent of 50 football fields of old-growth forest every minute, he warned.

“Rainforest regrowth is indeed occurring in regions but most old growth is destroyed,” he said.  “In biodiversity terms, this is akin to a barn door closing after the horses have escaped.”

The findings from the debate, and the evidence presented by the speakers, will be published as papers in a special edition of the journal Conservation Biology.

Source: Smithsonian press release

Date: 12/01/2009

Forests and farms ‘can fight climate change’


The problem of global warming from greenhouse gases calls for a stronger involvement of agriculture and farming communities, as well as forestry and forest users in reducing greenhouse gas emissions, the UN Food and Agriculture Organization (FAO) has said.

“Agriculture and deforestation are major contributors to climate change, but by the same token farmers and forest users could become key players in reducing greenhouse gas emissions,” said FAO assistant directo-general Alexander Muller.

“Unlocking the potential of agriculture and forestry for climate change mitigation requires financing mechanisms targeting farmers and foresters around the globe, particularly small-scale land-users in developing countries,” he added.

“These mechanisms should give priority to emission-reducing measures that have ‘co-benefits’ for food and energy security, poverty reduction, sustainable use of natural resources. Forestry and agriculture offer many opportunities for such ‘win-win’ measures.

According to the FAO, greenhouse gas emissions from forestry and agriculture contribute more than 30% of the current annual total emissions (deforestation and forest degradation accounts for 17.4%, while agriculture is responsible for 13.5%).

When looking at methane, the FAO says that agriculture is responsible for half of the annual emissions (primarily through livestock and rice), and more that 75% of nitrous oxide (largely from fertiliser application) emitted annually by human activities.

“Climate change will affect the lives and livelihoods of farmers, fishers and forest users in developing countries, many of whom are already facing difficulties in earning a sufficient income and feeding their families,” Mr Muller continued.

Rural communities, particularly those living in already environmentally fragile areas, face an immediate and ever-growing risk of increased crop failure, loss of livestock, and reduced availability of marine, aquaculture and forest products.

Humans, plants, livestock and fish also face the risk of being exposed to new pests and diseases.

Mr Muller concluded that climate change had the potential to increase hunger, particularly in the world’s poorest nations.

“We have to act now if we want to avoid a humanitarian disaster,” he said.

Roughly 40% of the land biomass is directly or indirectly managed by farmers, foresters or herders.

He added: “The international community can only win the global battle against climate change if we succeed in mobilizing the potential of these land users to reduce greenhouse gas emissions and in sequestering carbon in soil and plants.

“We have to adapt to climate changes that are of greater intensity and rapidity than in the past.”

Source: FAO press release

Date: 04/12/2008

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