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Follow explanation. LCDs are better.


It seems that LCD TV’s are environmentally friendly if you want good quality and low energy consumption.

Plasma: This particular TV display is probably the worst eco-friendly option to choose. While the picture is sharp and clear, “producing that perfect image requires a high resolution, and the higher the resolution, the more bandwidth—the rate at which data is transferred—the set needs,” according to GetDirectTV. Also, with any television, size matters. The bigger the set, the more energy and light it will take to illuminate the screen.

LCD: These sets seem to be somewhere in between Plasma and LED choices. While the technology of an LCD TV uses about a third of the energy consumption than Plasma, they still don’t quite beat the innovative technology of an LED TV.

One of the best tips for choosing a more environmentally-friendly television is to look at the Energy-Star rating that can be found on each TV display. And of course, as stated earlier, size does matter! Regardless of what kind of television you choose, the size will make the biggest impact. Remember, the bigger the size, the more energy consumption it requires. Not to say you have to sacrifice size or quality, but the amount of energy consumption is something to keep in mind.

Reference: http://www.isfoundation.com/campaign/environment-fight-club-plasma-vs-led-vs-lcd-which-television-most-environmentally-friendly


Energy changes from one from to another. Nutrients get used up by living things or get recycled.


In the universe, one thing is certain that energy is conserved . That means that energy can neither be created nor be destroyed. It can only be converted or transformed from one form to another.

In an ecosystem energy just changes form. For example, when we cycle, muscular energy is transformed to mechanical energy while peddling. This is why we say energy "flows".

Nutrients do have a definitive end cycle. They can be created and be destroyed or even recycled. That is why we say that nutrients "cycle" because something with a start and finish has a cycle.


The missing mass is the carbon dioxide and water released as by products of metabolism.


Each level of the food pyramid uses energy for metabolism necessary for life. The process of metabolism uses mass by burning glucose and other organic molecules to produce energy. Carbon Dioxide and Water are by products of the oxidation of the sugars, proteins and fats used for energy.

The first law of energy is that energy and matter can neither be created nor destroyed. What is happening here is the second law of thermodynamics. The second law says that energy always moves from a high useable level of energy to lower less useable forms of energy. The food used by organisms has a high level of useable mass and energy. When the food is burned the mass and energy is at much lower level of useable energy and mass. The mass released as Carbon Dioxide and Water are lost to the food pyramid.

Each level of the food pyramid uses 90% of the useable energy and mass it absorbs to maintain its own metabolism. There is only 10% of the useable mass and energy left to pass on next level of of the food pyramid. This is in accordance of the second law of Thermodynamics, not the first.


You may be interested in these related Socratic questions:
How does energy flow through an ecosystem?
How is a food chain related to energy flow within an ecosystem?
Can you describe the efficiency of energy transfer between trophic levels?


Animal agriculture has a significant and negative impact on the environment.


Animal agriculture has a significant and negative impact on the environment. The main impacts fall are 1. animal agriculture uses a lot of land, 2. greenhouse gas emissions from animal agriculture are higher than most realize and 3. the animal agriculture industry uses a lot of water.

  • Raising both the livestock and the crops needed to feed that livestock takes up a lot of space. The United Nation's Food and Agriculture Organization (FAO) estimates that of our ice-free land, 26% of it is used to graze livestock and 33% of it grows feed for livestock (source).


Methane is released when cows and other ruminants burp, and this GHG lasts much longer in the atmosphere than carbon dioxide. The GHG emissions tied to animal agriculture is also related to the amount of land used in this industry. Whenever land is converted from forests, which are carbon dioxide sinks, this process of removing the GHG from the atmosphere is replaced with less biomass and therefore a less effective CO2 removal method.

  • Animal agriculture uses a lot of water, as shown below for the United States for the year 2010.

Water is needed for the animals themselves but it is also needed to grow all of their feed. Beef has a particularly large impact: it takes 15,415 liters of water per kilogram of beef. If you look at the impact of a human and a dairy cow at the end of both of their lifespans, the dairy cow has a larger impact on water despite a much shorter lifespan (source)


Animal agriculture also has many of the problems agriculture has, and you can read about those here.

You can read much more in the United Nation's Food and Agriculture Organization's report on animal agriculture , or this article on livestock from the Smithsonian, or One Green Planet's article here.


An indicator species is an organism whose presence, absence or abundance reflects a specific environmental condition.


Indicator species are an appealing research and monitoring tool.
Indicator species can signal a change in the biological condition of a particular ecosystem, and thus may be used as a proxy to diagnose the health of an ecosystem.

For example, plants or lichens sensitive to heavy metals or acids in precipitation may be indicators of air pollution.

Indicator species can also reflect a unique set of environmental qualities or characteristics found in a specific place, such as a unique microclimate. However, care must be exercised in using indicator species.

Indicator species are sometimes called proxy or surrogate species.

  • In Vancouver, Canada, the environmental health of estuaries is
    monitored by the indicator species of eel grass. In open water
    ecosystems, yellow water lily is the indicator species.
  • Salmon are an indicator species for wetland ecosystems of Greater Vancouver as well as over the greater Pacific Rim
  • Indicator species for American grassland ecosystems, the five species of prairie dogs now occupy only about 2 percent of their historical range.
  • Non-Alaskan grizzly bears are indicator species for mountain
    ecosystems, measuring the health and diversity of the ecosystem.


It isn't actually anymore, but I'll elaborate.


Until about a year or two ago, you're right, the ozone layer was thinning. Due to some monumental actions to ban CFC's and other compounds that destroy ozone, it's actually repairing itself. It might take 50-100 years to go back to pre-damaged levels, but it'll get there.

CFC's are the main thing that deplete ozone so I'll focus on them. CFC's are/were released primarily from AC's (CFC's are good coolants), refrigerators (same reason), and computer parts. They rise up into the atmosphere where UV rays strike them, breaking off a chlorine atom. The chlorine breaks Ozone into O and O2, and then binds to the oxygen atom. The cycle will repeatedly let ozone reform and then get broken by chlorine, but there will be perpetually less ozone blocking UV-B rays.

One more thing: in the winter, the temperature drops in the south pole (and sometimes the north) to the point where ice crystals can form in the stratosphere to form polar stratospheric clouds. These trap CFC's and other chemicals, but when the sun emerges in the spring, a motherlode of ozone-destroying chemicals are released, leading to a huge increase in ozone depletion. See the graphic:NOAA

The ozone hole is being measured, and you'll notice (by the way, the seasons are switched so spring is actually in about september), that once spring arrives, the area of the ozone hole goes way up, and then gradually goes down. The stratospheric clouds aren't exactly what you're asking for, but they do have an impact on ozone depletion by CFC's and other compounds.

Bottom line: the ozone layer was thinning because of our releasing of CFC's, and other halogen-containing compounds such as methyl bromide and HNO3.

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