The Fall of the Water

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the access of industry to forest products, minerals, hydro power, oil and gas. Environmental pressures and threats include nuclear waste, toxic tailings from industry, pol- lution, sand storms, deforestation, overgrazing and erosion from increases in domestic animals, reduction in nomadism, unsustainable agricultural practices and loss of seasonal pastures and natural flood-buffers. Growing populations result in intensified land use prac- tices along road corridors, increased water consumption and increased vulnerability to climate change. This has resulted in increases in both nitrate and dissolved phos- phate levels in the rivers across the last decades (Fig. 2). While numerous water and participatory programs have been developed and some successfully directed towards individual and local issues, there are currently few, if any assessments of the large-scale long-term changes of hu- man settlement and resource exploitation in the region. Such major long-term changes may play a major role for the functioning of ecosystems and their services to people and should of particular interest for policy mak- ing as they may exhibit trans-boundary patterns. Such

household water, food, fisheries, jobs and cultural tradi- tions. Changes in the catchments and the rivers could be detrimental not only to individuals, but also to nations and welfare of several billion people in the region (Lu et al, 2003; Viviroli et al., 2003). Currently, both natural and human driven disasters are common throughout the region, including floods, land slides, earthquakes and glacial outbursts (Gerrard and Gardner, 2002; Yong and Yiqian, 2003). Problems are currently being exacer- bated by climate change which speeds up meltdown of high altitude glaciers at unprecedented rates. To the last part of the 20th century, the topography of the region largely functioned as natural protection to large- scale development, thereby providing unique gradients from largely untrammeled areas with only minimal im- pacts from pastoralism and subsistence type agriculture, to some of the most densely populated regions of this planet, thus preserving the precious water resources in the catchments. However, development of the infra- structure network in recent years has greatly increased

Figure 2: Increases in nitrate and dissolved phosphate levels between 1976-1990 and 1991-2000 in some of the major watersheds in the World show particular high changes in Asia.

Global Average Nitrate Levels Concentrations at Major River Mouths

Global Dissolved Phosphate Levels Concentrations at Major River Mouths

1991-2000

0.25 0.5 1 2 4 NO 3

-N mg/L

0.1 0.2 0.3 0.4 0.5 PO 4

-P mg/L

Insufficient data for analyses or region not included in study

Decreased levels

High

Medium Low No change

Increased levels

Low Medium

Changes Between 1976-1990 and 1991-2000

Low Medium

Changes Between 1976-1990 and 1991-2000

High

Insufficient data for analysis or region not included in study

MARCH 2002 PHILIPPEREKACEWICZ

MARCH2002 PHILIPPEREKACEWICZ

UNEP

Source: United Nations EnvironmentProgramme (UNEP) - Global Environment Monitoring System (GEMS) Water Programme 2001; National Water Research Institute Environment Canada, Ontario, 2001.

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