Arquivo de etiquetas: Florestas

Biodiversity IV

Deforestation

Forests remain one of the major parts of terrestrial ecosystems on the planet. e know that forests cover something around 30% of the total land area.

And we also know that forest cover used to be a far higher proportion of, the earth’s land area, before humanity got to it[1].

1341Humanity’s been in the business for thousands and thousands of years of clearing forests. And we read accounts of the massive deforestation in ancient Greece, or in the Roman Empire, or in ancient China and India thousands of years ago. This is an ancient story, but we continue to lose a lot of rainforest, and a lot of other forest areas today, because of the increasing populations and pressures on the planet and the forces of international trade. So what has been going on from ancient times, continues and in some ways, intensifies, till today. When we lose forests, we degrade ecosystems. We also lose a tremendous amount of biodiversity. Our rainforest areas, the three great rainforest areas of the Amazon basin, the Congo basin, and the Indonesian archipelago, are home to countless species and much of the greatest biodiversity on the planet. And as those rainforests are being depleted right now, or are at threat of massive deforestation and degradation, we are also losing huge amounts of biodiversity as well. This map gives us suggestion of the extent of past deforestation, and some of the challenges of current deforestation. Every area shaded in this map, is an area that originally had forest cover.

1342The very light shaded areas, let’s say in western Europe or across China, or across Russia and, the Eurasian land mass. The light shaded areas in the eastern half of the United States, are areas that were original forest cover that have been deforested. So western Europe, much of the eastern half of the United States, essentially all of China, lost its original forest cover to human activity. In the case of China, hundreds of years ago that process was already complete. India as well having lost a huge amount of its original forest cover. Europe having lost a huge amount of its original forest cover hundreds and in some cases thousands of years ago. Today, most deforestation is taking place in the fast growing tropical and subtropical regions. And notably in the rainforests where population densities were low traditionally.

But had been rising and where these rainforest regions are increasingly being encroached for human provisioning, for tropical log woods, or for clearing, for farm land, and for pasture land. Or for provisioning of peasant small holders who go into the forests for fuel wood, or for bushmeat or for other needs of people living on the margins, of the forest. And the result is that while temperate zone areas were deforested in historical time, it’s now the tropical areas that are under the most direct force of deforestation today. Not because there’s something intrinsic about tropical deforestation, but rather, in a way, from a historical point of view, because it’s coming last in line. It’s a, set of ecosystems that were relatively less disturbed previously, but now are facing major disturbances in human impacts. Some of that human impact is internally driven by growing populations within countries, within Brazil or within Central Africa for example, or in Southeast Asia. But, a huge amount I’m going to want to draw our attention to, is coming from international trade.

From demands halfway around the world for these forest products and this is very, very difficult to control because it means high levels of demand, often from rich countries or rapidly growing economies like China. Even overwhelmed local protective services. It’s easy to bribe. It’s easy to engage in illegal activities even when they are on the books under legal control. This map that you’re looking at now shows us the current patterns of deforestation. It emphasizes that in areas that were traditionally deforested, say, the eastern part of the United States or western Europe, or northern Europe, there is some reforestation taking place in those areas. That’s a very healthy point. But the red areas shown on this map are areas that the Millennium Ecosystem Assessment identified as being areas under a current intensive process of deforestation. And that includes parts of the tropical rainforests I’ve mentioned. Large regions in Southeast Asia. Of course the Andean region as well. Many parts of the world where there are remaining forests find those forests under threat. Forests are major providers and regulators of ecosystem services, and this means that the threats to these forests are threats to human well being. And it’s worth listening to the words of one of the great scientists of our age, James Lovelock who is the creator of the Gaia theory which is basically the theory of the interconnectedness of the world’s ecosystems and the interconnected regulatory processes of those ecosystems. Lovelock more than, most earth scientists, 30, 40, 50 years ago, emphasize the interconnectedness of the climate regulatory functions. that, and other natural flux functions of energy heat dissipation nutrient flows, and so forth, played by ecosystems. Emphasizing that when we degrade one ecosystem, we impede or undermine the functioning of ecosystems in other parts of the planet. So here’s what Lovelock says for example about the deforestation of the tropical rainforests. He says, and I’m quoting, no longer do we have to justify the existence of humid tropical forests on the feeble grounds that they might carry plants with drugs that cure human disease. Because he’s saying that was one argument that conservationists were emphasizing. Maybe the main one. Don’t cut down the rainforest, there maybe a lifesaving medicine there. There’s proof to that, but what Lovelock is saying is that’s not the only proof. Gaia theory forces us to see that they offer much more than this. Through their capacity to evapotranspirate vast volumes of water vapor, they serve to keep the planet cool by wearing a sunshade of white reflecting cloud.

1343So the rainforests have cloud cover above it. A lot of that cloud cover reflects the incoming ultraviolet radiation, sending it out into space, rather than having it hit the earth, warm the earth, reradiate as infrared. And so, the changing reflectance of the planet, caused by the existence of the rainforests is a regulatory feature of climate. Not intuitive, not of our everyday nature, but recognized by an interconnected earth systems science. So, Lovelock concludes their replacement by crop land could precipitate a disaster that is global in scale. The point, the point is that when we degrade large ecosystems such as tropical ecosystems, the impacts can be far more then we would recognize in the absolute direct impact of the loss of the local ecosystem services. Earth systems science teaches us that the interaction of the ecosystems in their global regulation of climate, water cycle, other nutrient cycle, nitrogen fluxes, are also of huge significance for planetary balances and for human well being. Well, the extent of degradation is enormous. The pressures are vast, and the pressures are coming from many different directions. Have a look at the island of Borneo, which is shared in the present day, by Malaysia and Indonesia. Malaysia, with its two states of Sabah and Sarawak. And Indonesia with the state of Kalimantan. This island is absolutely under the most incredibly rapid and deep transformation, because one of the most diverse, wondrous ecosystems of forest area is essentially being cut down and replaced by monoculture, for palm oil production. Palm oil is in huge demand, since palm oil is a very versatile product. It commands a good market price. It’s used in many home products. It’s used in cooking and for for home use. And it’s soared, in demand in recent decades.

And the maps that you’re looking at produced by UNAP, both show the actual decline of forest cover on the Island of Borneo. Up through the year 2005 and then projections that were made under a business as usual trajectory for 2010 and 2020. What you’re observing here essentially is deforestation to replace a highly biodiverse rainforest area with a monoculture of of palm oil. Now palm oil in limited production is okay and when it’s carefully monitored and measured and kept within certain boundaries, it can make sense. But if it sweeps the island of Borneo and as is similarly taking place in Sumatra and Indonesia, if you get a massive replacement of a diverse ecosystem with a monoculture, the losses will be phenomenal. The losses to regulatory functions of these ecosystems. The losses to biodiversity in the specific context of Indonesia, Malaysia.

1344Huge threats to the loss of, again, one of our closest Great Ape relatives, the orangutan whose habitat is precisely in these rainforest areas, whose numbers have declined, and whose habitat is under tremendous threat. And unless we take into account what is a sustainable harvesting of tropical forests. What is in the same way that we need to take into account the sustainable harvesting of fisheries, and other ecosystems. We will, before we know it, have lost these ecosystems. They will have fallen into an irreversible collapse. There’s an attempt to do something about it of course. In fact there are several attempts. One that is notable, is to link the conservation of the rainforests, and forests in general, with the climate change agenda. Because remember that perhaps 15% of the total carbon dioxide emissions each year are coming from land use change especially from deforestation. And so, the idea was taken several years ago that as part of the mitigation effort, not only should we be reducing our carbon footprint in the energy sphere, but also the carbon emissions coming from deforestation. And the project that has grown up from that is called REDD Plus, R-E-D-D Plus. Which stands for Reduced Emissions from Deforestation and Forest Degradation. And so, it’s both the thinning of forests and the clearing of forests that are the target of the REDD Plus Initiative. The idea, and it’s a good one, is to give financial incentives to farmers and to communities and to forest communities in general, often including indigenous populations. To protect the forests and to replace part of the income that in the short term they would lose from their over exploitation of the forest products, with a sustainable flow of income of other kinds including a top-up of income being provided by donor countries. Norway for example, has offered a billion dollars to Brazil. In a REDD Plus Initiative to slow or stop the deforestation of the Amazon, [COUGH] and to use this funding to create financial incentives for forest communities in the Amazon to play the role of protecting the Amazon rather than facilitating its loss. The map that you’re seeing here are the participating countries. The countries in red are countries that are actively receiving from the United Nations, support for developing REDD Plus programs. Other partner countries are shown in blue. It is a, an important effort. The funding by some countries like Norway has been extremely generous. But, it’s still a small counter pressure to an overwhelming force coming from the global marketplace for the products, either directly off the forests themselves, or for the products that are grown. The meat products or the soy beans or others that are grown, when the for, and palm oil, when the forest are cleared and replaced by other kinds of economic activity. Let’s look in more depth at programs like REDD Plus to see what the international response is to the loss of bio diversity. To see how that response is functioning to date, and to make a kind of assessment of how we might and need to strengthen that response, if we are to reverse the very powerful wave of species extinction and ecosystem loss that now is engulfing so much of the planet.

[1] http://earthenginepartners.appspot.com/science-2013-global-forest, http://www.earth-policy.org/indicators/C56/forests_2012.