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Disappearing forests Disappearing forests
From 1970 to 1990 there was significant deforestation of both primary and secondary forests in Thailand: during this thirty year period, the area covered by primary and secondary forest declined by more than half.
29 Nov 2007 - by Philippe Rekacewicz, UNEP/GRID-Arendal
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Conversion of terrestrial biomes Conversion of terrestrial biomes
It is not possible to estimate accurately the extent of different biomes prior to significant human impact, but it is possible to determine the “potential” area of biomes based on soil and climatic conditions.
30 Nov 2007 - by Philippe Rekacewicz, Emmanuelle Bournay, UNEP/GRID-Arendal
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Millennium Ecosystem Assessment conceptual framework Millennium Ecosystem Assessment conceptual framework
International demand for timber may lead to a regional loss of forest cover, which increases flood magnitude along a local stretch of a river. Similarly, the interactions can take place across different time scales. Actions can be taken either to respond to negative changes or to enhance positive changes at almost all points in this framework.
30 Nov 2007 - by Philippe Rekacewicz, Emmanuelle Bournay, UNEP/GRID-Arendal
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Changes in forest area Changes in forest area
Timber is harvested from forests and plantations and used for a variety of building, manufacturing, fuel, and other needs. Forests (providing fuelwood and charcoal), agricultural crops, and manure all serve as sources of biomass energy.
30 Nov 2007 - by Philippe Rekacewicz, Emmanuelle Bournay, UNEP/GRID-Arendal
4
Main direct drivers of change in biodiversity and ecosystems (CWG) Main direct drivers of change in biodiversity and ecosystems (CWG)
The cell color indicates impact of each driver on biodiversity in each type of ecosystem over the past 50–100 years. High impact means that over the last century the particular driver has significantly altered biodiversity in that biome; low impact indicates that it has had little influence on biodiversity in the biome. The arrows indicate the trend in the driver. Horizontal arrows indicate a continuation of the current level of impact; diagonal ...
30 Nov 2007 - by Philippe Rekacewicz, Emmanuelle Bournay, UNEP/GRID-Arendal
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Annual flow of benefits from forests in selected countries Annual flow of benefits from forests in selected countries
In most countries, the marketed values of ecosystems associated with timber and fuelwood production are less than one third of the total economic value, including non-marketed values such as carbon sequestration, watershed protection, and recreation.
30 Nov 2007 - by Philippe Rekacewicz, Emmanuelle Bournay, UNEP/GRID-Arendal
3
Locations reported by various studies as undergoing high rates of land cover change in the past few decades Locations reported by various studies as undergoing high rates of land cover change in the past few decades
In the case of forest cover change, the studies refer to the period 1980–2000 and are based on national statistics, remote sensing, and, to a limited degree, expert opinion. In the case of land cover change resulting from degradation in drylands (desertification), the period is unspecified but inferred to be within the last half-century, and the major study was entirely based on expert opinion, with associated low certainty. Change in cultivated ...
30 Nov 2007 - by Philippe Rekacewicz, Emmanuelle Bournay, UNEP/GRID-Arendal
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Number of ecosystem services enhanced or degraded by 2050 Number of ecosystem services enhanced or degraded by 2050
100% degradation means that all the services in the category were degraded in 2050 compared with 2000, while 50% improvement could mean that three out of six services were enhanced and the rest were unchanged or that four out of six were enhanced and one was degraded. The total number of services evaluated for each category was six provisioning services, nine regulating services, and five cultural services.
30 Nov 2007 - by Philippe Rekacewicz, Emmanuelle Bournay, UNEP/GRID-Arendal
4
Forests in the Caucasus ecoregion Forests in the Caucasus ecoregion
About 17% of the total land area of the Caucasus is covered by forests, primarily found between altitudes of 500-2000m and growing on steep slopes. Most forests are broadleaf forests but a number of different types are found, including birch forests, oak forests, fir forests, alder forests and wing nuts forests. In Georgia the total area covered by forests is 40% while forest areas in the Northern Caucasus amount to 11.4%, in Azerbaijan to 14-15%...
01 Nov 2008 - by WWF-Caucasus, design Manana Kurtubadze
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Forest vs. Agriculture – the case of the Mabira forest reserve, Uganda Forest vs. Agriculture – the case of the Mabira forest reserve, Uganda
The Mabira forest reserve, on the shores of Lake Victoria hosts valuable wildlife, serves as a timber resource, provides ecosystem services for the water balance and the rainforests represents a tourist destination. Following a proposed plan for clearing a third of the reserve for agricultural use, the values of the forest were calculated by local researchers. This economic evaluation of the forest shows that from a short-term perspective, growin...
12 May 2008 - by Hugo Ahlenius, UNEP/GRID-Arendal
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World map of forest distribution (Natural resources - forests) World map of forest distribution (Natural resources - forests)
Approximately 240 million of the world's poor that live in forested areas of developing countries depend on forests for their livelihoods. Forest and its products provide cash income, jobs, and consumption goods for poor families. Forestry provides formal and informal employment for an estimated 40-60 million people. The sector contributes in some developing countries more than eight per cent to GDP. Timber may be the most important forest produc...
12 May 2008 - by Hugo Ahlenius, UNEP/GRID-Arendal
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Reforestation, town of Galma and surroundings, Niger 1975 and 2003 Reforestation, town of Galma and surroundings, Niger 1975 and 2003
In 1970s and 1980s - years of environmental crisis, there were few trees remaining in Niger. Wind-blown sands razed farmers' young crops and they often had to plant crops three times to succeed. Since the middle of the 1980s in the most densely populated parts of Niger farmers have begun to protect and manage young trees and bushes regenerating on their cultivated fields. This is natural farmer-managed forest regeneration. Some trees fix nitrogen...
01 Oct 2008 - by Hugo Ahlenius, UNEP/GRID-Arendal
3
Vegetation density/distribution in the high Arctic Vegetation density/distribution in the high Arctic
The current vegetation density and distribution in the high Arctic can be calculated using satellite images. The vegetation index, 'greenness' (NDVI) represents a benchmark of the presence and ratio of photosynthesis. In monitoring the vegetation, scientists can keep an eye on the situation and use the index as an indicator of climate change - increased temperatures would enable the forest and tundra to move further north.
31 Jul 2008 - by Hugo Ahlenius, UNEP/GRID-Arendal
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Temperate forests Temperate forests
Temperate forests are active carbon sinks and deforestation in the temperate zone has largely stopped. Where demand for land and/or water allows, reforestation would enable carbon sequestration and could provide other benefits including higher biodiversity and recreation opportunities.
06 Nov 2009 - by Riccardo Pravettoni, UNEP/GRID-Arendal
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Boreal forest Boreal forest
The boreal forest biome holds the second largest stock of carbon; most of this is stored in the soil and litter. The draining of boreal forest peatlands, inappropriate forestry practices and poor fire management may all cause significant losses of the carbon stored in this ecosystem.
27 May 2009 - by Riccardo Pravettoni, UNEP/GRID-Arendal
5
Temperate Forests Temperate Forests
Temperate forests are active carbon sinks and deforestation in the temperate zone has largely stopped. Where demand for land and/or water allows, reforestation would enable carbon sequestration and could provide other benefits including higher biodiversity and recreation opportunities.
13 Sep 2009 - by Riccardo Pravettoni, UNEP/GRID-Arendal
5
The vicious cycle of depletion The vicious cycle of depletion
Agricultural systems in the temperate zone tend to occupy fertile soils that would have formerly supported temperate grassland or forest. Land clearance for croplands and pasture has greatly reduced above ground carbon stocks from their original state and soil carbon stocks are also often depleted as tillage disrupts the soil, opening it to decomposer organisms and generating aerobic conditions that stimulate respiration and release of carb...
27 May 2009 - by Riccardo Pravettoni, UNEP/GRID-Arendal
3
Tropical forests Tropical forests
Tropical forests hold the largest terrestrial carbon store and are active carbon sinks. Reducing emissions from deforestation and degradation is a vital component of tackling dangerous climate change. In addition, tackling illegal and ill-managed logging will be an important part of reducing emissions from forestry.
06 Nov 2009 - by Riccardo Pravettoni, UNEP/GRID-Arendal
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Logging in the Congo river basin forest Logging in the Congo river basin forest
China is the largest consumer of logs from the DRC, buying near 38% of the roundwood produced in official statistics in 2008 (Ministère des Eaux, Forêts, Chasses et Pêches du DRC, 2009). However, the official numbers only reflect approximately half of what is being cut, the remaining illegally, often transported across borders to neighboring countries.
17 Mar 2010 - by Riccardo Pravettoni
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Mining the forest Mining the forest
Mining and deforestation.
01 Mar 2010 - by Riccardo Pravettoni
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