Species Approach

When there are no more animals of a particular species left alive, that species is said to be extinct.

In the distant past, several species of animals became extinct through natural causes. There might have been a change in the climate of a particular region, and the plants or animals on which the species lived could have died out because of the change in the weather. Or one animal might have been destroyed by another that was stronger or faster.

But ever since human beings have been on Earth, and especially in the last hundred years, animal species have become extinct because of hunting, pollution, or the destruction of the places where they live.

So many animals are now in danger of extinction that a list is kept in a Red Book. unfortunately, the list gets longer every year.

Characteristics of animals prone to extinction

Endemic species

• Low reproductive rate
• Specialized niche
• Feeds at high trophic level
• Fixed migratory level
• Commercially valuable

Invasive species vs. Ecosystem

Invading species success because:

• High reproductive rate
• Wide life span
• High dispersion rate

The new ecosystem is adequate because there are not direct depredators, the climate conditions are the correct ones.

Disadvantages:

• You just focus your efforts in just one species
• Not holistic
• ‘Cause not all the variable are considered you could miss a higher priority
• Connections between species, biotic and abiotic factor cannot be ignored

Opposing View Points: Global Warming

Photochemical smog

Photochemical smog is a type of air pollution produced when sunlight acts upon motor vehicle exhaust gases to form harmful

Irritates the eyes a

Peroxyacetylnitrate. Nitrogen dioxide, oxygen and hydrocarbons react with the sunlight.

Catalytic Converters.Is a strategy that tries to reduce the emission of carbon monoxide and nitrogen oxide production. It uses platinum or radium  (reduce the amount) The unburned hydrocarbons are catalyzed to produce carbon dioxide and water vapor. 

The catalytic convertors needs to promote the necessary rate of acting over the combustion, reducing first the nitric oxide to nitrogen gas to avoid the oxidation of the carbon dioxide

The ozone Is form outside the combustion chamber when the nitrogen oxide (NO2) is divided between nitrogen and oxygen. Then the oxygen reacts with other particles of oxygen in the air to form ozone.

Eutrophication

Too many nutrients, algae grows, there is no light, plants die, there is oxygen depletion

The primary causes for eutrophication are anthropogenic Detergents and fertilizer
However there is the case of natural causes.
Eutrophication will cause at the end the dead of many organisms in the body water, most of the times because the lack of oxygen.
This phenomena is specially harmful in slow moving water bodies.

How do we stop it?

• Controlling the runoff from crop fields and from urban areas
• Control the amount of fertilizers used in agricultural practices
• Develop buffer zones around body water. Growing plants around them. The plants will absorb the excess of nutrients
• Set water treatments on sewage sources.
• Oxygenize the water
• Drench the sediment off the water.

Wastes, Disposal and Strategies for Control

Type of Waste	Disposal	Strategy for control
Heavy Metals	Landfills. If not properly confined the leachate may pollute soil/ground water.	Mixed with cement and additive that encloses the sludge.
Nuclear Wastes	Depends on the type of waste: -For low levels, material is compressed and buried in landfills -For inter, level it may be solidified in concrete and buried -For high level, it is placed in a container Reuse (weapons, not cost-effective; hybrid reactors)	Very difficult. Confinement is needed wastes take thousands of years to decay. An option is to deplete highly radioactive materials
Organic Wastes	Pumping wastes into deep wells. The mulch is used as fertilizer. Land —> provides biogas.	Biotech processes open / closed composting use microorganisms or worms. Aerobic / anaerobic bacteria break down organic matter. Incinerators /pyrolysis
Plastic Wastes	Landfills Incinerators. Reuse/recycling	Efficient incineration provides useful thermal energy and control of the gases released. Treatment Conversion into fuels (Polymer Energy System)
Oils and Solvents	Small amount placed in containers and put in trash, landfills Larger amounts, containers for recycling; oil –> biofuels. Incinerators	Bioprocesses –> microorganisms break down molecules into simpler compounds.

 

 

Method	Description
Landfills	Confinement of wastes into an area, covered by soil
Incineration	Wastes are burned
Recycling	Materials are changed and used in other products
Reuse	A new use is find for materials or they are reused for the same purpose.

 

 

Pollution management: A three level model

Pollution cannot be eliminated by just deciding that we won't use electric power, nor if we just stop developing industries. Pollution cannot be erased, but we can do something about it. The course of action must be treated from three different basis. The generation of the pollutants, the release of them and the impact that they have on the environment at the long-run. This is describe as a three level model:
Human activity producing pollutant
Improve human attitude towards taking consideration of the environment equilibrium towards
education: people would know the real sources of pollution and the effects they have over the environment. The point is that they actively engage in the pollution management and take a part of creating alternative processes.
incentives and penalties: the behavior of the people is difficult to change. Sometimes even if we understand the awful conditions, caused mainly by human action, of the environment, we don’t want to take part of improving them. Incentives and penalties might be the answer to push people and motivate them to take part of the change.

• Development of alternative tech
  
• Adoption of alternative lifestyles
  
• Reducing, reusing, recycling. Recycling campaigning are nowadays supported all around the world, but even if they are helpful and have positive effects, it should be the last R to implement. First we must try to reduce the resources that we use and trying to reuse this resources in every possible way.

Polluting Disposable Container.

Release of pollutant into the environment
Regulating and reducing at points of emission. A lot of businesses are working without caring about the impact that they have over the environment. They want to reduce costs and increase profit. What to do?

• Standards. I mean, if we know that something is doing harm why not to stop it. Regulation could be the solution. If applied, businesses will be forced to care. Maybe at the end they will find their own real ecological consciousness.
  
• Measures to extract pollutants on ecosystem

Long term impact of pollutant and reducing ecosystem
Clearing up pollutant and restoring ecosystem:

• Extracting and removing pollutant from ecosystem
  
• Replanting and restoring animal populations

Indicator Species

Aquatic ecosystems
Oyster: They fed on organic material and pollutants in the water. They filter the water, removing the particles.
Vertebrate and invertebrate species: Found in rivers and streams. Can determine the grange pollution to kept in check.
Lilies: rivers, lakes, ponds and swamps. They absorb oxygen and sunlight. Indicate abundance of nutrients, which leads to eutrophication.

Mayfly larvae: Native specie that are adapted to live in certain biome. When its number decreases it is a very clear sign that the pollution levels are increasing. They reappear downstream as the effects of the discharge are diluted. This help to indicate the level of pollution in water.
Sludge Worm. Common in lakes and rivers. All fresh water ecosystems. They fed on the sediments and bacteria, hence a great population on them might indicate great pollution in the body water and oxygen-poor water. They indicate stagnant water unfit to drink.
Soil Indicator species
The plants that are found in certain soil might indicate the presence or absence of a specific substance.
Besides plants, there are many other indicators.
Birds eggs can be analyze to find out pesticide sin the soil.
Invertebrates:. Indicator species to identify the use of foreign soils, insecticides, pesticides, and other pollutants.
In Canada there are plans to use soil-living arthropods in order to quantify the pollution in the forests.
A good way to measure the healthiness of an ecosystem and to determine the presence of pollution is biodiversity. High biodiversity indicates a strong and healthy environment.

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