Earth Science: Environmental Exploitation – Water At Risk
Water is one of the most valuable resources on Earth. There should be sufficient water available to cover the demands of the world population. How-ever, there is a shortage of clean water due to the increasing pollution.
Colliding tankers, damaged platforms and pipelines, as well as the release of residual oil from oil tanks, are potential causes for catastrophes. Pictures of dying seabirds show the extent of such environmental damage. Not all environmental hazards are this obvious.
Water pollution due to pesticides and heavy metals, such as mercury, lead, cadmium, and zinc, largely remains unnoticed and can be a slow and often invisible process. The dangerous prior assumption that the oceans could naturally purify themselves without limit, doubling as dump sites for industrial and nuclear waste, and as final disposal sites for chemical weapons and discarded ships, has caused possibly irreparable damage.
Not only the oceans, but many creeks, rivers, and lakes have also suffered from human interference. Many lakes have become polluted due to the chemicals added by household wastewater and the overfertilization with phosphates in agriculture. Moreover, unknown effluents from industry and acid rain add to the acidification of water bodies, which contributes to the decrease of biodiversity. Pollutants accumulate in the tissue of aquatic organisms that are part of the same food chain as humans.
Groundwater deterioration
Surface water and groundwater constantly interact with each other. Normally, ground- water is of a higher quality than surface water. This is due to the natural purification process during the passage of water through various rock layers in the ground. However, this purification effect is limited. In many areas, the groundwater is relatively close to the surface and is contaminated by nitrates from fertilizers and pesticides leaking into the soil due to their excessive usage in large areas.
Pollutants may also leak into the groundwater from contaminated sites or local landfills. Furthermore, fossil water reservoirs, which have been stored under- ground for thousands of years—for example, beneath the Sahara-stand the risk of depletion if used extensively for irrigation or industrial purposes.
BASICS
WATER USAGE in industrialized nations is at a daily average of 38 gallons (145 I) per person, while 2.2 billion people worldwide have no access to clean water.