For most of the time that humans have inhabited the earth our wastes were only of significance on a local level. In recent decades society has started to take seriously the impact of human actions on the planet in a broader sense. Pollution of the air, land and water comes from a variety of sources and continues to be a major issue for communities and countries across the globe. While measures have been taken to address pollution in various ways across many dimensions – from local waste collection and recycling programs to international hazardous waste protocols -- globalization has magnified the problems as pollution is often exported along with good and services. One of the major challenges of the 21st century is to find ways for a growing human population to reduce the amount and impact of contaminants we discharge to our shared natural resources.
Debris scatters in the Pacific Ocean, possibly heading to United States.
Debris from the tsunami that devastated Japan in March 2011 could reach the United States as early...
Herman Daly Festschrift: Restructuring taxes to create an honest marketLast Updated on 2013-10-07 22:49:40The market is in many ways an incredible institution. It allocates resources with an efficiency that no central planning body can match and it easily balances supply and demand. The market has some fundamental weaknesses, however. It does not incorporate into prices the indirect costs of producing goods. It does not value nature’s services properly. And it does not respect the sustainable yield thresholds of natural systems. It also favors the near term over the long term, showing little concern for future generations.
As economic decisionmakers—whether consumers, corporate planners, government policymakers, or investment bankers—we all depend on the market for information to guide us. In order for markets to work and economic actors to make sound decisions, the markets must give us good information, including the full cost of the products we buy. But the market is... More »
PollutionLast Updated on 2013-09-22 22:58:20Pollution is environmental contamination that results in harm or death to living organisms. Most pollution is in the form of chemical additions to air, water or soil; however, in modern times starting in the mid-twentieth century noise and light have been considered as pollution sources. Most pollution is man-made, with natural fluctuations in atmospheric composition, surface water bodies and soil considered temporal gyrations in the Earth's natural history. The chief driver of pollution is the massive growth in human population, which induces the proximate causes of intensive agriculture and extraordinary industrial output. The United Nations and the Blacksmith Institute are two prominent organisations that tabulate locales of the greatest pollution intensity; while their listings do not correspond precisely, the overlap countries that both entities agree are the worst polluted... More »
Water pollutionLast Updated on 2013-09-12 18:10:41Water pollution is the contamination of natural water bodies by chemical, physical, radioactive or pathogenic microbial substances. Adverse alteration of water quality presently produces large scale illness and deaths, accounting for approximately 50 million deaths per year worldwide, most of these deaths occurring in Africa and Asia. In China, for example, about 75 percent of the population (or 1.1 billion people) are without access to unpolluted drinking water, according to China's own standards. Widespread consequences of water pollution upon ecosystems include species mortality, biodiversity reduction and loss of ecosystem services. Some consider that water pollution may occur from natural causes such as sedimentation from severe rainfall events; however, natural causes, including volcanic eruptions and algae blooms from natural causes constitute a minute amount of the... More »
Diesel Particulate MatterLast Updated on 2013-09-05 19:28:25
This article was researched and written by a student at Mount Holyoke College participating in the Encyclopedia of Earth's (EoE) Student Science Communication Project. The project encourages students in undergraduate and graduate programs to write about timely scientific issues under close faculty guidance. All articles have been reviewed by internal EoE editors, and by independent experts on each topic.
Diesel particulate matter (DPM) is a complex mixture of elemental carbon (EC) particles, soluble organic carbon, including 5-ring or higher polycyclic aromatic hydrocarbons (PAHs) such as benzo(a)pyrene, as well as other metallic compounds. Also, DPM usually contains some small amounts of nitrates, sulfates and sulfuric acid—that is created through reaction of sulfates with water molecules present in the air during ignition or after release into ambient air. Also,... More »
Contemporary evolutionLast Updated on 2013-07-18 16:32:36
Rapid environmental change, whether human induced such as fishing and hunting pressures, toxic chemicals, or natural climatic changes resulting in altered food availability have provided opportunities to observe rapid microevolutionary changes in contemporary time, or contemporary evolution. These are population level changes which tend to occur over a few centuries or much less time (depending on the species) and may be observed after only a relatively small number of generation cycles depending on the species. Well known examples of contemporary evolution include pesticide and antibiotic resistance. Yet we now know that animals other than pest species can evolve in response to rapid environmental change (including chemical expsoures).
However distinguishing rapid, adaptive genetic change from phenotypic plasticity (altered phenotypic expression of a single... More »
Drag and drop the content to change the order of featured content. The top nine will be displayed.