Climate warming means that lowland lakes typically are experiencing longer ice-free periods, promoting greater biological productivity. However, despite this warming trend, biological productivity may be reduced, at least temporarily, in alpine areas with increased winter precipitation. During years with high winter precipitation in alpine areas of western Norway, in spite of higher temperatures, fish growth and recruitment were lower than in low...

Hydropower, generating electricity through turbines, represents a clean and renewable energy source, but not without problems. Dams and reservoirs disrupt the natural flow, and may increase siltation and evaporation, in addition to severe impacts for wildlife, for instance migrating fish. The gross theoretical capability, presented in this map, represents a calculation based on the topography and precipitation in the countries, and is the amount ...

Fisheries catches increasingly originate from deep areas. Over the years due to depletion in fish stocks the fishing industry has resorted to fishing at greater depths and increasing the damage to fish stocks and the ocean floor.

Marine systems are the world’s oceans. For mapping purposes, the map shows ocean areas where the depth is greater than 50 meters. Global fishery catches from marine systems peaked in the late 1980s and are now declining despite increasing fishing effort.

From the late 1950s, offshore bottom trawlers began exploiting the deeper part of the stock, leading to a large catch increase and a strong decline in the underlying biomass. Internationally agreed quotas in the early 1970s and, following the declaration by Canada of an Exclusive Fishing Zone in 1977, national quota systems ultimately failed to arrest and reverse the decline.

Fishing production dramatically increase through the century peaking in late 1980s. At this time there were major declines in several fish populations in different areas of the world. The catch reported by governments is in some cases adjusted to correct for likely errors in data.

A trophic level of an organism is its position in a food chain. Levels are numbered according to how far particular organisms are along the chain from the primary producers, to herbivores, to predators, to carnivores or top carnivores.

This map shows protected areas, priority conservation areas and wildlife corridors identified in 'Eco-regional Conservation Plan for the Caucasus'. Priority conservation areas were agreed where there is important concentration of plants, mammals, birds, amphibians, reptiles and fishes. Delineation of corridors were agreed where large mammals, birds, fish, and other animals need corridors for migration, dispersal and to maintain their population. ...

Climate models project that summer sea ice in the Arctic Basin will retreat further and further away from most Arctic landmasses, opening new shipping routes and extending the navigation season in the Northern Sea Route by between two and four months. Previously frozen areas in the Arctic may therefore become seasonally or permanently navigable, increasing the prospects for marine transport through the Arctic and providing greater access to Arcti...

Fisheries, together with tourism, represents a major economic activity around Antarctica. In the old days whales were hunted for oil - these days fish and krill are captured for fish meal and human consumption. The areas in the Southern Atlantic are vastly more productive, and this is where most of the fish is caught. The top fishing vessels hail from Japan, Ukraine and Poland. Worth mentioning is that these figures are still small compared to th...

Current projections for aquaculture suggest that previous growth is unlikely to be sustained in the future as a result of limits to the availability of wild marine fish for aquaculture feed (FAO, 2008). Small pelagic fish make up 37% of the total marine capture fisheries landings. Of this, 90% (or 27% of total landings) are processed into fishmeal and fish oil with the remaining 10% used directly for animal feed (Alder et al., 2008).

Food losses in the field (between planting and harvesting) could be as high as 20–40% of the potential harvest in developing countries due to pests and pathogens (Kader, 2005). Postharvest losses vary greatly among commodities and production areas and seasons. In the United States, the losses of fresh fruits and vegetables have been estimated to range from 2% to 23%, depending on the commodity, with an overall average of about 12% losses b...

Sea ice represents a unique ecosystem in the Arctic, providing habitat to specialized iceassociated species that include microorganisms, fish, birds, and marine mammals. Individual species use sea ice in different ways depending on their biological needs. Ice algae form the base of the food web. Some algae stay attached to the bottom of the ice, some fall into the water column, and some fall to the bottom of the sea, and so provide food for speci...

The harvest of natural resources is a key feature of traditional lifestyles and economies throughout the Arctic, and a continuing reliance on it as a mainstay of indigenous existence in the north is evident. In Alaska, wild food harvests vary considerably by geographic area. The total harvest has been estimated at about 43.7 million pounds (approximately 19.8 million kg) of wild resources, an average of about 375 pounds (170 kg) per capita. This ...

Distribution and spawning areas of arctic cod, polar cod, herring and capelin in the Barents Sea region. The Barents region is in the Arctic and covers the area of Western Russia and the northern areas of Finland, Sweden and Norway.

Illustration in a set of graphics prepared for a pilot assessment report on the Black Sea drainage basin, for the UNEP Global Impact on Waters Assessment (GIWA). All data and information were prepared in close collaboration with the GIWA Black Sea team and the GIWA secretariat. The graphics were never not used in this form in the final report on the Black Sea, published in 2005.

Illustration in a set of graphics prepared for a pilot assessment report on the Black Sea drainage basin, for the UNEP Global Impact on Waters Assessment (GIWA). All data and information were prepared in close collaboration with the GIWA Black Sea team and the GIWA secretariat. The graphics were never not used in this form in the final report on the Black Sea, published in 2005.

The thick-billed murre and common murre have ranges 1,000,000 km2 and number in the millions or tens of millions of breeding pairs. However global populations are declining, although increases have occurred in some regions. These seabirds, together with other species of alcids, face a number of direct and indirect marine and terrestrial threats, which influence their survival and reproductive success. These include transboundary pollutants, by-ca...

Climate change poses a threat to wildlife because as climatic conditions change, many species may be unable to tolerate the changes. This graphic shows the numbers of mammals, birds, reptiles, amphibians and fish species that are critically endangered, endangered and vulnerable in various regions of Africa and in Africa as a whole, as of 1998.

The potential impacts of sea level rise on the Nile Delta are expected to include a decline in water quality that would affect freshwater fish, the flooding of agricultural land and damage to infrastructure. This graphic shows the Nile Delta region as it is today (2002), the area as it would appear with a 0.5 m sea level rise, and the area as it would appear with a 1.0 m sea level rise.