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Water
Published in Cameron La Follette , Chris Maser, Sustainability and the Rights of Nature, 2017
Cameron La Follette , Chris Maser
A dead zone is an aquatic area lacking sufficient dissolved oxygen to support life. Today, the world’s oceans are being increasingly plagued by human-caused dead zones (analogous to an “oxygen desert”), of which 530 occur near inhabited coastlines worldwide, where aquatic life is most concentrated. A dead zone is caused by a process known as “eutrophication” triggered by an excess of plant nutrients from fertilizers, livestock manure, human sewage, and other pollutants. However, the use of chemical fertilizers is considered the major human-related cause of dead zones around the world. (“Eutrophic” come from the Greek eutrophia [“healthy, adequate nutrition”] and the Greek eu [“good”] plus trophe [“food” or “feeding”] which taken together means “well fed.” Thus, “eutrophication” is the process of being well fed.)
Evaluation of Water and Its Contaminants
Published in William J. Rea, Kalpana D. Patel, Reversibility of Chronic Disease and Hypersensitivity, Volume 5, 2017
William J. Rea, Kalpana D. Patel
Dead zones are hypoxic (low-oxygen) areas in the world's oceans and large lakes, caused by “excessive nutrient pollution from human activities coupled with other factors that deplete the oxygen required to support most marine life in bottom and near-bottom water. (NOAA).”117 In the 1970s, oceanographers began noting increased instances of dead zones. These occur near inhabited coastlines, where aquatic life is most concentrated. The vast middle portions of the oceans, which naturally have little life, are not considered “dead zones.”
Introduction to the special issue on source-to-sea management
Published in Water International, 2021
Josh Weinberg, Qinhua Fang, Sarantuyaa Zandaryaa, Greg Leslie, James E. Nickum
The dynamic interface between land, freshwater, coasts and oceans captures a key environmental challenge of our time. Unsustainable human activities are imposing a heavy burden on the ecosystems at this interface, while the impacts of climate change amplify the challenges faced. This can be seen in numerous areas. It is found in the form of the millions of tons of plastic that enter the ocean from land-based sources each year. It is evident in the eutrophication and spread of dead zones in our coastal and marine waters that are caused by excessive nutrient loads from unmanaged agricultural runoff and inadequate wastewater treatment. It is apparent in areas where the flows of rivers are so highly diverted that little or no water reaches the sea. This robs coastal ecosystems of the water, sediment and nutrients they need, aggravates seawater intrusions into coastal aquifers and leads to the recession of deltas. The resulting degradation of freshwater and marine environments has a direct impact on ecosystem services, and the livelihoods of all of those who depend upon them for food and economic security.