Water: the basis for life Chiara Gozzi. Università degli studi di Milano, Scienze Umane dell'ambiente, del Territorio e del Paesaggio. Facoltà di Lettere e Filosofia . Liberal Sciences of Land, Landscape and the Environment. University of Milan.
Water's molecule contains one oxygen and two hydrogen atoms They are connected by covalent bonds (chemical bonding characterized by the sharing of pairs of electrons between atoms).
a major problem in developing countries as many people in these areas don’t have access to sanitary conditions and clean water. In developed countries, sewage often causes problems when people flush chemical and pharmaceutical substances.
Wastewater often contains faeces, urine and laundry waste and can contaminate the environment; causing diseases such as diarrhoea. Sewage carries harmful viruses and bacteria into the environment causing health problems.
Contaminated waste water pours into a public canal in Thailand from a industrial treatment plant.
from oil spills routine shipping run-offs and dumping
They cause a very localized problem that can be catastrophic to local marine wildlife. Oil forms a thick sludge in the water. This suffocates fish, gets caught in the feathers of marine birds stopping them from flying and blocks light from photosynthetic aquatic plants.
Marine life off the coast of Louisiana has been devastated by the BP oil spill
caused by air pollution. In the atmosphere, water particles mix with carbon dioxide sulphur dioxide and nitrogen oxides, this forms a weak acid. When it rains the water is polluted with these gases, this is called acid rain. It pollutes marine habitats and aquatic life is harmed.
ACID RAIN EFFECTS acid rain harm buildings, it damages trees and kills aquatic life and other organisms.
Wind and rain have always had an effect on buildings, but the main cause of deterioration is pollution Acid rain has dissolved part of this artwork (statue located in Westphalia, Germany) Photos from 1908 and 1968
The process where the average global temperature increases due to the greenhouse effect.
An increase in water temperature can result in the death of the acquatic wildlife.
a rise in water temperatures causes coral bleaching of reefs that's when the coral expels the microorganisms of which it is dependent on. Photograph of a bleaching hard coral (goniopora sp) Pohnpei, Micronesia. Photo taken by J Hoogesteger.
Phytoplankton grows and reproduce more rapidly, resulting in algal blooms. the environment becomes over-enriched with nutrients
Algal blooms disrupts normal ecosystem functioning: algae use up all the oxygen in the water, they also block sunlight from photosynthetic marine plants under the water surface; some algae even produce toxins that are harmful to higher forms of life