The major components of the Earth are water, air/gases, minerals, organic and biological components, microorganisms and gases.
There are 5 types of mineral including Water. The percentage of the components vary from time to time.
MINERAL- It is the largest component of the soil and makes about 45% of the soil. It consists of sand,silt and clay. It retains the soils ability to retain important nutrients.
WATER- It is the second basic component of the soil. It may vary from 2% to 50% of the soil. It usually contains added salts and other chemicals.
AIR/GASES- About half of the total mass of the soil has many cavities and holes. It makes 2 to 50% of the soil. The air found in the Earth or soil is very different from the air found in the atmosphere.
ORGANIC AND BIOLOGICAL COMPONENTS- It is the next basic component found in levels of approximately 1% to 5%.It has a very high water holding capacity and thus it can increase the fertility of the soil.
MICROORGANISMS- These are found in the soil in a very high number but covers only 1% of the soil. These are the primary decomposers of the raw materials present in the soil.they eat(consume) water,air and organic matter to recycle raw materials into humus. Other microbes like Nitrogen fixing bacteria helps the plants in intake of the nitrogen gas.
FOR MORE INFORMATION PLEASE FOLLOW THIS SITE- http://articles.extension.org/pages/54401/basic-soil-components.
The conventional answer is "it formed by the Chapman mechanism", which implies that the layer was created when the atmospheric concentration of oxygen was sufficient.
A theory for the origin of this ozone layer was proposed in 1930 by a British scientist, Sydney Chapman, and is known as the Chapman mechanism. The basis is that ultraviolet light breaks the bond between two oxygen atoms in molecular oxygen at high altitude. The highly-reactive single oxygen atoms attack molecular oxygen which is in contact with a third non-reacting agent. However, ozone is unstable and will revert to oxygen by a reverse process. Thus the ozone layer is the result of an equilibrium between the splitting, the formation of the ozone, and its decay back to oxygen.
This implies that the ozone layer gradually built up in step with the increase in concentration oxygen in the atmosphere once plants appeared and photosynthesis got under way.
The Chapman hypothesis was re-examined in the 1980s as a result of political pressure to reduce the production of CFCs. Some people argue that it is flawed in a way that Chapman could not have known in 1930 as quantum mechanical calculations had not been sufficiently developed. The flaw is that the energy in an ultra-violet quantum is insufficient to break the bond, at least in the mechanism as accepted. This issue has become important because some people believe that CFCs interfere with the Chapman Mechanism and might cause a reduction in ozone concentration. The current position is unclear.
coal power plants are good for many reasons. But to always remember what has a good side always has a bad one.
coal power plants exit high amounts of heat as its and exothermic reaction that takes place. hence many thermal plants can be set up near it
coal is a stable source of energy and there is no sudden scarcity like that happens with other fuels.
It increases job opportunities and employs more people in the industry.
lastly coal is the cheapest source available
with many other alternative sources found coal industry has the cheapest means of getting electricity. ( though hydroelectricity would be the cheapest , but construction of dams and displacement of people is not accepted by large masses.)
These are the reasons why its good. but most of the time coal industry degrades the environment. we need to remember that and understand that even if is the most cheapest source ---- its high time we start shifting
It influences greenhouse gas (GHG) emissions and has direct environmental impacts as well.
One of the biggest pollution problems right now is that in developing countries, their population is exploding, but they don't have the money for efficient (expensive) energy and technology. Many of these countries end up using inefficient methods of producing energy and heat, such as burning wood in large open fires, which is extremely inefficient.
There are a whole bunch of ways this affects the environment, so I'll focus on the impacts in countries that can't afford more efficient energy.
First: going back to my example of people cutting down trees, this has a plethera of environmental impacts. The trees are sinks for carbon dioxide, so burning them releases this into the atmosphere and contributes to climate change. Additionally, less trees means less habitat and food for wildlife and a weakened ecosystem, increased erosion (because of a lack of root systems and unhealthy soil) and less rainfall (the reason for this is somewhat complicated, but essentially trees both need rain and attract it).
Second: countries that burn a lot of fossil fuels or wood inefficiently are going to experience an increase in numerous water and air pollutants. For example, excessive coal burning releases nitrous oxide, a major greenhouse gas, so it contributes to climate change, and releases many other pollutants that directly impact the surrounding environment, most notably mercury. Mercury is toxic to many aquatic species if it makes its way into the water supply, and makes its way up the food chain, and thus weakens ecosystems on all trophic levels.
In less efficient energy production, there's much more wasted energy production potential, so you end up releasing more pollutants compared to how much fuel was used.
Natural Selection does not lead to adaptation in a population.
Natural selection leads to extinction. Variation of the genome that do not have the information required to survive in an environment are eliminated due to natural selection. The surviving genomes already had the information required to survive or adapt to the environment.
Natural selection does not create information necessary for the adaptation of a population. The information must already exist for adaptation to occur. Natural selection will change the composition of a population by eliminating the poorly adapted.
Examples are the peppered moth of England. There were two varieties the Melanic or dark and the predominate white. When the industrial revolution and burning of coal changed the environment, the Melanic or dark variation was better adapted. The population changed to being predominately melanic. When the pollution caused by the Industrial revolution was brought under control the population reverted back to the predominately white variety. Natural selection only changed the population. Natural selection did not create the adaptation it already existed.
Another example is the Cheetah of the Eastern African Savannah. The Cheetah that had the genetic information for speed survived and passed on that information to their offspring. There is now so little genetic variation in the Cheetah population that a change in the environment would not lead to further adaptation but to extinction of the Cheetah population.
Natural selection does not create adaptations in a a population but only choses the existing adaptations best suited to a changing environment.
Crop output is improved, price is a little higher in some cases.
It'd take five pages to go through all the pros and cons, so I'll sum up the major ones.
1) Crop output. Data about sustainable agriculture suggests that crop output is actually improved because soil nutrients are consistently higher and never degrade, so crops always have a good source of nutrition. In addition, sustainable agriculture fosters growth of natural microbes that act symbiotically with plants to give them more nutrients. Basically sustainable agriculture means more profit overall.
2) Runoff and erosion. Both of these are significantly reduced in sustainable agriculture because crops can be rotated year-round, runoff from fertilizer is generally decreased, and, as mentioned previously, the healthier soil is less prone to erosion. An example that shows this is during the Dust Bowl, when unsustainable agriculture coupled with a drought caused massive crop die-off, and the topsoil completely disintegrated (hence the "dust" in "dust bowl").
3) Lower prices. Farmers don't have to spend money on artificial fertilizers because the soil is healthy and replenishes itself. They don't have to invest in expensive herbicides and pesticides because the farm is a more robust ecosystem that can tolerate disturbances by invasive or competing species.
Really the main one is that you can't grow quite as many crops at a time because sustainability generally means downsizing the crop just a bit so that the plants don't leach the nutrients out of the soil. So for mass agriculture, it can be difficult to manage sustainable farming practices. However, as these practices evolve, they will no doubt become more feasible for mass agriculture, and will likely actually become beneficial for ensuring better crop yield and pest control for large monoculture farms.
Source: Took AP Environmental Science
It can be made more sustainable and more friendly to the surrounding ecosystems.
Overgrazing is a large issue on rangelands. If cattle populations are controlled, they can all have enough food to survive, which, although it brings profits down short-term for ranchers, saves money in the long run and saves cattle from being undernourished.
A large problem with rangelands is that they interfere with the wildlife surrounding it unnecessarily. Example: Ranchers put barbed wire fences around their rangeland to prevent animals from getting on their land, but although it protects against bison and wolves that might hurt the cattle, it also hurts pronghorns, which are harmless. When faced with an obstacle, pronghorn don't jump, but dive down, which ends really badly when barbed wire is there.
One project I know of involved putting a smooth barrier under the barbed wire so that the pronghorn could pass through, but still kept out animals that might hurt the cattle or compete with them.
Source: Took an Environmental Science class.
Well, we're hurting it through climate change, development, hunting, pollution, habitat loss and degradation, and invasive species.
Currently, we're in the sixth mass extinction. Since humans established a dominant presence on the planet, the rate of species extinction has risen to between 1,000 and 10,000 times the normal rate.
Here are a few causes:
Climate Change : Change in temperatures and precipitation globally (including and especially in oceans) have led many species, who are are unable to keep up with the rapidly changing conditions, to go extinct.
Structures and industrial development : In the last 50-100 years, the US has built dams in almost every place it could. Dams prevent natural migrations of fish, build up sediment in places where it shouldn't be, increase flooding, and decrease soil nutrition content in areas downstream of it.
This has led to the extinctions of a plethora of species, many of which we haven't even been able to identify. However, a lot of them have a large impact on the ecosystem's health and the diversity of species.
Hunting : The number of animals we've hunted to extinction or near extinction is astonishing. Even in the many cases where measures were taken to prevent the extinction of a species, such as with many of animals in Africa (lions, cheetahs, rhinos, elephants, etc.), the decreased population of these animals has proven to be very detrimental to their ecosystems, greatly decreasing their species diversity, and thus the health of the ecosystem.
Pollution : Between the oil spills, mining runoff and byproducts, fertilizer and agricultural runoff, industrial waste, not to mention the coal, natural gas, and oil we have been burning since the industrial revolution, this is a significant way we have impacted species diversity. The number of species that have been severely damaged or forced to extinction by the pollutants we emit in the air and water is pretty staggering.
Habitat loss and degradation : While connected to impacts mentioned above, humans have substantially altered the surface of the earth through urbanization, building of infrastructure, expansion of agriculture, and resource consumption. This has lead to major changes and loss of habitat. Habitat is degraded when roads cut through forests, when light pollution from cities invades natural darkness, when selective logging occurs, and so forth.
introduction of invasive species : Whether purposefully or accidentally, humans have introduced non-native species to new habitats and at times this has had drastic consequences. Invasive species often have no predators or controlling population effects and thus out compete natural species. For example, cane toads are linked to species extinctions and the Guam broadbill is now extinct in part due to invasives.
Natural Selection does not affect the frequency of mutations.
Mutations are the result of random accidental changes in the genome. The DNA is an informational code. Mutations are accidental changes, additions, and loses of information in the DNA.
Natural selection does not affect the frequency of mutations. Natural selection can only cause the extinction of mutations that are not well adapted to the environment,
An example of a helpful mutation is sickle cell anemia. A mutation causes an A to switch places with a T on the DNA. This mutations causes the red blood cell to break open in a sickle shape. This loss of information allows the white blood cells to attack the malaria organism that hides in the red blood cell. In malaria zones this mutation is helpful. In non malaria zones the trait is harmful and tends to be eliminated from the population.
Mutations may increase the number of variations available for natural selection to act on. Natural selection does not cause mutations. Natural selection can only act to eliminate harmful mutations.
Nuclear power plants do not produce air pollution or use limited fossil fuel reserves and are less expensive. The problem is the nuclear waste.
Limiting the answer to nuclear power plants
Nuclear power plants do not produce air pollution.
Coal or oil fired plants produce Carbon Dioxide, ( climate change) Sulfur Oxides (Acid Rain) and particle immersions. ( asthma)
Nuclear power plants do not use up precious oil and coal reserves, or food produces for fuel.
gasohol,removes corn from food production to energy production.
oil removes petroleum from plastic production to energy production
Nuclear power plants are less expensive to operate than traditional power plants using other energy sources. ( Hydroelectric is cheaper but places to build dams are limited)
Nuclear power is a somewhat unlimited energy source. Uranium 238 is changed in a nuclear power plant into Plutonium 238, Plutonium 238 can be used in turn to power new power plants.
A. The nuclear waste produced by power plants is a very dangerous substance. Uranium 238 has a half life of 4.5 billion years. The waste will remain dangerous for as long as it thought the earth has existed. No adequate solutions have been found for the safe storage of the nuclear waste produced by nuclear power plants.
B. The Plutonium 238 is a source not only for power but for atomic bombs. Uranium 235 was used to make the first atomic bomb. Uranium 235 is a rare substance. Plutonium 238 was used to make the second atomic bomb, it was produced from the "waste" in making the Uranium 235 bomb. Nuclear power plants contribute greatly to nuclear proliferation and possibly a nuclear war.