All About Water

What Are Introduced Species?

Introduced species are species that now live outside of their native range. These species are introduced to new areas–usually over previously inaccessible bodies of water–by human activity, either deliberately or accidentally. The Environmental Protection Agency defines introduced species as “species that have become able to survive and reproduce outside the habitats where they evolved or spread naturally.”

The Terminology of Introduced Species

Scientists are ambivalent about introducing species to areas that they don’t naturally inhabit. Introduced species are introduced to these new areas by accidental or deliberate human activity. Introduced species can harm the ecosystems of the places that they’re introduced to. However, sometimes introduced species can have no effect on or even help the ecosystems they’re introduced to. For instance, some of the plants that Europeans brought into North America have aided the continent’s biodiversity and productivity. Because introduced species can spread too quickly for us to control and can sometimes help us, most environmentalists consider it impractical and undesirable to simply prohibit introducing non-native species.

How We Refer to Introduced Species

Scientists refer to introduced species by many terms, like “non-indigenous,” “non-native,” “exotic,” and even “invasive.” The broadest term applied to introduced species is “non-native,” which can be applied to both agriculturally maintained and wild species. Some introduced species can survive by themselves in nature when introduced—these are “naturalized” species. “Invasive” species threaten ecosystems by spreading or reproducing too widely or too fast, thereby harming the environment or human health.

How We Introduce Species: Intentionally Introduced Species

Through human activity, we introduce species to places that they don’t naturally inhabit. Sometimes we introduce species accidentally, and sometimes intentionally. People usually introduce species intentionally because they will economically gain by doing so. For instance, New Zealand introduced the Monterey Pine to bolster timber crops. We have also introduced species for recreational activities, like game hunting or ornamental gardening. We have also introduced species by bringing pets overseas. When we try to establish introduce these species in the wild, we often have trouble predicting how well the introduced species will fare. For this reason, we often have to make several attempts to establish an introduced species.

Accidentally Introduced Species

Sometimes people accidentally introduce species to new areas. For example, we have spread many rat species spread across the world by unintentionally transporting them aboard ships. Human travel also introduces several species to places where they don’t naturally inhabit. For example, tourists introduced the African killer bee to Brazil.

What Is Salt Marsh?

Salt marsh is an ecosystem that occurs between land and saltwater, an ecosystem that helps protect the coast. Salt marshes are populated by salt-tolerant plants like herbs, grasses and shrubs. These plants allow the salt marsh to trap sediment. The salt marsh then exports these nutrients to the coast. Salt marsh also creates a habitat for land-bound animals like mammals and migratory birds.

Where Do We Find Salt Marsh?

Salt marsh occurs on temperate coasts in sheltered environments like estuaries and embankments. In tropical areas, salt marsh is replaced by mangroves, marshes populated by salt-tolerant trees instead of salt-tolerant herbs. Salt marsh frequently occurs along the deltas of large rivers, like the Mississippi.

Salt Marsh is Unique

Unlike land-bound habitats, coastal salt marsh ecosystems are flooded by tidal flow every day. This tidal flow helps deliver sediments to salt marsh. The nutrients that collect in salt marshes make them highly productive environments that enable a broad food chain of organisms. In salt marshes we can find everything from bacteria to mammals. However, to survive, salt marsh organisms must be tolerant of salinity and flooding. Flora further inland are less exposed to salinity and flooding, and therefore don’t usually need to be as hardy, allowing inland salt marsh flora more diversity.

How Humans Have Harmed Salt Marsh

People flock to salt marshes for their beauty and coastal location. In 2002, over half of the world’s population lived within thirty-five miles of the coast. However, our population density along coasts means that we greatly impact salt marshes, often in negative ways. In the past people perceived marshlands as near-wasteland, and we used “land reclamation” to convert these areas into upland for agricultural purposes. After that, this upland was sometimes again converted into urban or industrial land, as in the cities of Boston and Tokyo. We have polluted salt marsh with runoff and nitrogen loading, introducing new species while killing off old ones. However, by altering marshlands, we have altered the salt marsh ecosystem. We’ve devastated salt marshes’ biodiversity and natural water flow.

Salt Marsh Perception and Restoration

Nowadays people are trying to restore salt marsh and reverse land reclamation. People no longer perceive salt marshes as “coastal wastelands,” and now see how biologically productive these areas are. In terms of biodiversity, people now perceive salt marshes as similar to tropical rainforests. Legislation such as the United States’ Clean Water Act now protects salt marsh habitats.

An Overview of Endangered Fish and Marine Animals

Humans have left a strong mark on the world. Unfortunately, that mark sometimes comes at a hefty cost. Because of overfishing or damage to their natural habitat, many fish and sea animals are now threatened, endangered or on the verge of extinction because of overfishing or damage to their natural habitat. Atlantic salmon, leatherback sea turtles, blue whales, smalltooth sawfish, and coral reefs are just some of the creatures on the list of endangered fish and marine animals.

Endangered Fish and Marine Animals: Atlantic Salmon

Atlantic salmon once swam in every river north of the Hudson. Today, the remaining wild Atlantic salmon population can only be found in eleven rivers. Only about fifteen to thirty-five percent of eggs laid by spawning salmon will survive through the fry stage because their habitats have been destroyed by acidified water, climate change, thermal pollution, the introduction of competitive non-native species, and poaching.

Endangered Fish and Marine Animals: Leatherback Sea Turtles

Leatherback sea turtles are not only the largest species of turtle, but the largest living reptile in the world. Generally these turtles remain in the open ocean, but they return to coastal areas to breed and forage. They make the list of endangered fish and marine animals for several reasons. The turtles are ingesting marine debris, they are continually entangled in nets and fishing gear, their eggs and females are being harvested, their environment is being contaminated, and they are bombarded with infection and disease

Endangered Fish and Marine Animals: Blue Whale

Blue whales once numbered in the hundreds of thousands. Today, their population worldwide is estimated at 8,000. The blue whale’s decline is primarily attributed to the overfishing of the whaling industry.

Endangered Fish and Marine Animals: Smalltooth Sawfish

Smalltooth sawfish belong to the chondrichthyes class of animals, which includes skates, rays and sharks. This class is composed of fish with cartilaginous skeletons, rather than bony ones. Sawfish are known for their distinctive long snouts, which are ringed around with teeth that are used to locate and kill prey. Smalltooth sawfish are included among endangered fish and marine animals because of their low population growth, frequent net entanglement, and loss of habitat.

Endangered Fish and Marine Animals: Coral Reefs

Although at first glance a coral reef may appear similar to stone, it is in fact composed of tiny creatures. Coral reefs are not only alive, but they also provide a habitat for many other creatures. Currently, about two-thirds of the world’s coral reefs are damaged; ten percent of the world’s reefs are damaged beyond repair. Human activity has caused about sixty percent of that damage. We’ve condemned coral reefs to the list of endangered fish and marine animals by polluting, developing along coasts near coral reefs, mining coral for ornamental purposes, introducing non-native species to their ecosystems, and aiding climate change.

Water and Biodiversity in the Freshwater Biome Is Under Attack

In July of 2010, the United Nations declared access to safe drinking water a human right. This resolution follows years of global campaigning to bring recognition to the problems of safe water and sanitation access. About 884 million people cannot access safe drinking water, and more than 2.6 billion people cannot access basic sanitation. More than two million people die annually due to a lack of clean drinking water and diseases caused by contaminated water. Diarrhea caused by drinking infected water is the second largest cause of the death of children under five years old.

Access to water has always been an important factor in the location of settlements, whether primitive or modern, human or animal, and the need for water is a universal part of life. Unfortunately, billions of people around the world still lack access to potable water.  Water shortages are usually defined as third-world phenomena, but shortages of clean water are also prevalent in the United States.  As the world’s population grows, humanity must recognize that water access is becoming an increasingly global concern.

Access to Clean Water

Access to water is vital, but access to clean water is even more critical.  Today, approximately one billion people do not have access to clean water, which has severely harmed the health and economic development of the most affected regions.  Further, according to UNICEF, lack of safe water is the world’s single largest cause of illness. Lack of clean water can cause afflictions such as river blindness, cholera, diarrhea, dysentery, and a number of other diseases and infections. The global water crisis is not unsolvable, though. Countries around the world are actively pursuing solutions such as reduction of pollution, infrastructure building, desalinization, improved irrigation, and more.

Data Concerning Water Usage

• A person needs 7.5 to 15 liters a day for survival. Included in this are figures for drinking water, hygiene and cooking.
• On average, women in Africa and Asia walk about 6 kilometers to collect water.
• More than 3½ million people die each year from water-related diseases.
• A child dies every 20 seconds from a water-related disease.

Access to Water and Sewage Treatment

In man’s effort to stay safe, he has found ways to treat water. Water treatment occurs before the water enters a house. Unfortunately, water treatment is so simplistic that many people are still concerned for population safety. Sewage treatment is done on used water before it re-enters the source, such as a river or under ground supply. Sewage treatment speeds the process of eutrophication, or the aging process of water, and creates favorable breeding grounds for disease that would not be as concentrated if nature took care of itself. Taking the larger particles from sewage water is acceptable, but the later-stage biological processes are what cause eutrophication.

Access to water and particularly, clean water will always present a major problem to the human race. Unfortunately, there are too many people needing too many resources from the planet.

Tropical Rainforests: The Good, The Bad, and The Facts

The Destruction of the Rainforest

Passed by Congress in 1974, the Safe Drinking Water Act (SDWA) is the bedrock of all other US federal laws regulating the quality and safety of drinking water. It authorizes the Environmental Protection Agency (EPA) to set standards for the safety of public drinking water, and forces states to comply. This involves regulating the levels of certain contaminants that may be found in the water supply, protecting the sources of the water, and setting requirements for the purification of water in public systems.

Effect on Water Quality

Before the Safe Drinking Water Act was passed, the US had established the Clean Water Act but had no national standards for determining or enforcing the safety of drinking water. What standards existed were established at the state or local level. How strong they were and how well they were enforced varied greatly. The Safe Drinking Water Act directed the EPA to identify contaminants in drinking water supplies that presented serious health risks, set limits on how much of these contaminants would be allowed in the water, and enforce those limits. As a result, many public water supplies nationwide became safer over the next few decades.

Immediate Results of The Safe Drinking Water Act

In 1975, months after the Safe Drinking Water Act passed, the EPA began testing the municipal water supplies in 80 cities for certain chemicals identified as carcinogenic.[] These chemicals came from sources as diverse as industrial pollution, agricultural runoff, natural sources, and even chlorination, the process of adding chlorine to the municipal water supply, which was meant to kill harmful bacteria. By June 1977, all states and municipalities were required to establish systems for testing their public water for contaminants, test regularly, and inform consumers of any risks they identified.[]

How Water Sources are Protected by the Safe Drinking Water Act

Initially, the EPA focused its efforts on removing identified pollutants from public water systems. Later amendments to the SDWA expanded the efforts to protect the original sources of the water. Reservoirs, lakes, streams, and groundwater are all covered by EPA regulations under the Safe Drinking Water Act. Under these regulations, the water must be tested regularly. Identified pollutants are to be removed as much as possible. In case of serious contamination, consumers must be notified. When a source of pollution is identified (ie industry or agricultural runoff), steps must be taken to stop the pollution.

Who Enforces the Safe Drinking Water Act?

While the EPA has primary responsibility for setting and enforcing the SDWA, most of the actual work is done at the state and local level. States are required to establish standards for drinking water safety that are in line with the SDWA.