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
World's top seed companies
The top ten seed companies have incomes at over $10 billion USD. Monsanto and Dupont/Pioneer lead the way with over 50% of seed sales in the world. All of the top ten companies are located in the U.S.A, Japan or Europe.
03 Jan 2008 - by IAASTD/Ketill Berger, UNEP/GRID-Arendal
Trends in real commodity prices
Agriculture is a fundamental instrument for sustainable development; about 70% of the world’s poor are rural and most are involved in farming. National policy needs to arrive at a balance between a higher prices which can benefit producers and lead to a more vibrant rural economy, and lower prices, which, although volatile on the international market, can improve food access for poor consumers.
03 Jan 2008 - by IAASTD/Ketill Berger, UNEP/GRID-Arendal
Natural resources - minerals
In more than hundred countries around the world, miners dig minerals and metals out of the ground, satisfying a slowly but continuously increasing demand from industrial production, agriculture, construction, high-tech sectors, and merchandise producers. In contrast to the other natural resources presented here, minerals are a finite resource, and the resource and their profits needs to be managed carefully to ensure sustained livelihoods after t...
12 May 2008 - by Hugo Ahlenius, UNEP/GRID-Arendal
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
Temperature increases in the Antarctic due to climate change, 2090 (NCAR-CCM3, SRES A2 experiment)
Climate change, due to increased concentrations of greenhouse gases in the atmosphere, has not lead as clear changes in the Antarctic as in the Arctic. Some of the ice shelves of the Antarctic peninsula have split up and started moving more rapidly, but the analyses of the Antarctic ice sheet are inconclusive. The projected climate situation in 2090 are presented in this figure, the temperatures are annual values from the NCAR-CCM3 model, ensembl...
31 Jul 2008 - by Hugo Ahlenius, UNEP/GRID-Arendal
Projected temperature increases in the Arctic due to climate change, 2090 (NCAR-CCM3, SRES A2 experiment)
Climate change, due to increased concentrations of greenhouse gases in the atmosphere, has lead to increased temperatures and large scale changes in the Arctic. The Arctic sea ice is decreasing, permafrost thawing and the glaciers and ice sheets are shrinking. The projected climate situation in 2090 are presented in this figure, the temperatures are annual values from the NCAR-CCM3 model, ensemble averages 1-5 for the SRES A2 experiment. The ice ...
31 Jul 2008 - by Hugo Ahlenius, UNEP/GRID-Arendal
Trends in productivity 1981-2003 (greening and land degradation)
Unsustainable practices in irrigation and production may lead
to increased salinization of soil, nutrient depletion and erosion.
An estimated 950 million ha of salt-affected lands occur
in arid and semi-arid regions, nearly 33% of the potentially arable
land area of the world. Globally, some 20% of irrigated
land (450,000 km2) is salt-affected, with 2,500–5,000 km2 of
lost production every year as a result of salinity (UNEP, 2008).
02 Feb 2009 - by Hugo Ahlenius, UNEP/GRID-Arendal
Disappearing lakes - Old Crow Basin, Canada (1951-2001)
The Arctic contains a variety of types of lakes but overall, it is thermokarst lakes and ponds that are the most abundant and productive aquatic ecosystems in the Arctic. They are found extensively in the lowland regions of western and northern Alaska, Canada and Siberia. These (i.e., thaw) lakes are most commonly formed by the thaw of ice-rich permafrost, which leads to the collapse of ground levels and ponding of surface water in the depression...
01 May 2010 - by Hugo Ahlenius, UNEP/GRID-Arendal
Disappearing Arctic lakes - examples in Siberian lakes, 1973 to 1997
The Arctic contains a variety of types of lakes but overall, it is thermokarst lakes and ponds that are the most abundant and productive aquatic ecosystems in the Arctic. They are found extensively in the lowland regions of western and northern Alaska, Canada and Siberia. These (i.e., thaw) lakes are most commonly formed by the thaw of ice-rich permafrost, which leads to the collapse of ground levels and ponding of surface water in the depression...
01 May 2010 - by Hugo Ahlenius, UNEP/GRID-Arendal
Marine mammals in the Arctic
Seven species of marine mammals live in the Arctic year-round – the bowhead whale, beluga whale, narwhal, ringed seal, beaded seal, walrus, and polar bear - and many more migrate to the Arctic seasonally. Many marine mammals aggregate in specific areas across the Arctic, for example to feed, or for whelping, pupping or moulting. A common feature of marine mammals in the Arctic is that they are associated with sea ice, although the ecological rela...
13 Oct 2010 - by Riccardo Pravettoni, UNEP/GRID-Arendal
Climate impacts and tropical diseases in Colombia
Shows comparative trend between air temperature in Colombia and levels of malaria and dengue fever. When temperatures increase, especially in combination with more precipitation, vector borne diseases like malaria and dengue fever increase in frequency and distribution. In particular, areas where the minimum night temperatures increase provide the best conditions for the growth and spread of Anopheline spp. and Aedes aegypti mosquitoes. (McCarth...
17 May 2005 - by UNEP/GRID-Arendal
Traditional practices, infrastructure and development
Indigneous peoples have lived in Arctic for thousands of years, and continue to depend upon the natural resources of the region today. Their traditional subsistence practices include hunting, trapping, fishing and reindeer herding. All of which are conducted in a sustainable manner; that is, in a way that does not lead to long-term or large-scale degredation of the environment.
However, the balance they have achieved with the environment through...
21 Mar 2006 - by Hugo Ahlenius, Philippe Rekacewicz, UNEP/GRID-Arendal
Fishing yield
Three-quarters of the world’s fish stocks are currently exploited to the maximum extent, if not in excess (FAO, 2000). This exploitation has had the following impacts:
- A growing variety of fishery products are being exploited. Commercial fishermen are targeting progressively smaller species at lower levels of the food chain because the main predator species are being depleted.
- Most of the world’s main fishing areas are close to full exploit...
26 Jan 2009 - by Phillippe Rekacewicz, February 2006
The disappearance of the Aral Sea
The demise of the Aral Sea in central Asia was caused primarily by the diversion of the inflowing Amu Dar’ya and Syr Dar’ya rivers to provide irrigation water for local croplands. These diversions dramatically reduced the river inflows, causing the Aral Sea to shrink by more than 50%, to lose two-thirds of its volume, and to greatly increase its salinity. At the current rate of decline, the Aral Sea has the potential to disappear completely by 20...
26 Jan 2009 - by GRIDA
Nitrate levels: concentrations at river mouths
Nutrients are essential to life. In aquatic systems, nitrogen and phosphorus are the two nutrients that most commonly control the growth of aquatic plants, algae and bacteria. Nitrogen and phosphorus are considered to be the primary drivers of eutrophication of aquatic ecosystems, where increased nutrient concentrations lead to increased primary productivity. Some systems are naturally eutrophic, whereas others have become eutrophic as a result o...
26 Jan 2009 - by Philippe Rekacewicz
Human actions leading to coastal degradation
Physical alteration and the destruction of habitats are now considered one of the most significant threats to coastal areas. Half of the world’s wetlands, and even more of its mangrove forests, have been lost over the past century to physical alterations, the major causes being accelerating social and economic development and poor-planning (UNEP, 2002).
There are currently about one billion people living in coastal urban areas. It is estimated t...
26 Jan 2009 - by Philippe Rekacewicz (Le Monde diplomatique), February 2006
The WWF living planet index for freshwater
'The over-exploitation and mismanagement of fisheries, particularly when combined with other man-made stresses, can lead to the collapse of regional fish faunas. In many countries, aquaculture is rapidly increasing in response to declining natural fisheries, often exacerbating the degradation of inland and coastal ecosystems through habitat alteration, pollution and the introduction of alien species' (Revenga et al., 1998).
The Freshwater Specie...
26 Jan 2009 - by GRID-Arendal
Transboundary water governance - averting conflict
Most governments recognize that violence over water is seldom strategically workable or economically viable and the most hostile enemies have a capacity for cooperation where water is concerned. The institutions that they create to avert conflict have shown extraordinary resilience. The considerable time taken to negotiate the establishment of these institutions - 40 years for the Jordan agreement for example - bears testimony to the sensitivity ...
26 Jan 2009 - by GRID-Arendal
Marine species diversity
Limited information is available on species diversity and the condition of coastal and marine ecosystems (Burke et al., 2001). There is growing evidence that many marine species are less widely distributed, and therefore more vulnerable to extinction, than previously thought (GESAMP, 2001a). The protection and sustainable use of marine resources and biodiversity are governed by several international conventions, including the Convention on Biolog...
26 Jan 2009 - by World Resource Institute (WRI), Washington Dc, 1998, based on data from UNEP-WCMC.