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17

Answer:

The names explain the purpose: pyramids are graphical representation of different aspects of ecosystem. Pyramid of energy is always upright which may not be so for pyramid of numbers or pyramid of biomass.

Explanation:

Energy pyramid depicts flow of energy in the ecosystem: source of all energy in ecosystem is the SUN. Producers are only organisms in ecosystem who can trap the solar enrgy. So base of energy pyramid is always wide.

upload.wikimedia.org

Now let us see a pyramid of numbers which depicts the number of individual organisms per trophic level: in an orchard producers are some large trees, but the trees will support a large number of consumers, such as insects and birds. A pyramid of numbers in such ecosystem will be inverted as seen in the following illustration:

www.dave-cushman.net

A biomass pyramid shows the total dry mass of all living organisms at each trophic level. An inverted pyramid of biomass could be seen when we study aquatic ecosystems, like a lake. The phytoplanktons at a given time is less in biomass but their lifecycle is very short; they actually reproduce faster than the consumers dependent on them.

http://www.drishtiias.com/upsc-exam-gs-resources-Ecological-Pyramid

1

Answer:

Depends on waste characteristics and other factors.

Explanation:

Hazardous wastes cause environmental damage ifnot managed properly. As of 1991, hazardous waste dominated the $8.2 billion environmental consulting market (LaGrega et al., 1994).

The environmental and human/environmental health consequences of the residuals and wastes of our technological community were not understood or even recognized initially; it took years or decades for chronic effects to manifest themselves, and those cases were obscured by the fact that everybody is exposed to a wide number of hazardous compounds.

There is no single and perfect solution for hazardous wastes. Incineration might cause further atmospheric contamination, landfilling may create groundwater contamination, and solidification techniques might be useless in long time to control hazard of hazardous wastes, etc..

The question, indeed, if there is a hazardous waste to be managed, what are hazardous constituents (factors) in it, state of it (liquid, sludge, or solid), decompositon (decay) mechanisms (temperature, climate, etc.), etc. Then you can get an initial idea, whether it is really a must to manage this case or you could take precautions to care it in the future.

Reference:

LaGrega, M. D., Buckingham, P. L., Evans, J. C. (1994) "Hazardous Waste Management" McGraw Hill, Inc. New York, NY, USA.

1

Answer:

Follow explanation. LCDs are better.

Explanation:

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

3

Answer:

North Africa is under the descending part of the Hadley cell of the Northern Hemisphere.

Explanation:

To answer this we need to look at global circulation.

enter image source here

https://en.wikipedia.org/wiki/Hadley_cell

The atmosphere around the Equator is heated. Since a lot of the Equator is over ocean a lot of moisture will be injected into the atmosphere here. The heating of the atmosphere causes expansion, and the inject of water vapor causes a decrease in pressure, both of which cause the air to rise.

Rising air cools since the air pressure drops and a drop in pressure causes the temperature to drop also. This is Gay Lussac's law which says that for a constant volume pressure and temperature are directly proportional. The ability of dry air to hold water vapor is determined by the temperature. Shown on the graph below.

enter image source here

The red line indicates the amount of grams of water vapor per kilogram of air. You can see as the temperature drops the amount of water vapor drops off pretty rapidly. As a result the water vapor in the rising air condenses. This condensation is accompanied in a release of latent heat which is the heat that is stored in the water molecules in order to change state. That means as the vapor turns to liquid it releases air.

On the first diagram where we see the Hadley cell you can see as the air rises it moves north. This air, having had a lot of the water vapor condense, is warmer and drier. Since we already discussed that water vapor is lighter than dry air, the air is now heavier and it begins to sink. Since we have a higher temperature to start with, and sinking air does not pick up any humidity, the sinking air gets warmer than it was when it was at the Equator and much much drier. So around 30 degrees latitude, where the Hadley cell ends, we get a lot of dry air and consequently deserts around the world.

Take a look at the globe and see how many deserts are at 30 degrees latitude. The Sahara, the Thar the Chihuahuan, the Sororan , the Lut and the Gobi are all at or close to 30 degrees latitude. In the Southern Hemisphere we see similar results with the deserts of Southern Africa and Australia at 30 degrees latitude.

Rain shadow and orographic lift do cause local deserts, but the Hadley cells is what create large deserts.

1

Answer:

Biomass at the 4th trophic level would be relatively smaller than at a 3rd trophic level.

Explanation:

The best way to think of biomass is to break it down into simpler terms. If we take the mass of let's say a Great White shark and multiplied it by the entire amount of Great White sharks in the same trophic level, we can then calculate biomass .

4th trophic level sharks (let's assume there are 3 of them)

800 kg each, the biomass for sharks in that trophic level would just be 3 sharks x 800 kg = 2400 kg.

3rd trophic level fur seals (let's assume there are 20 of them)

200 kg each, the biomass for fur seals would be 20 fur seals x 200 kg = 4000 kg

And as we continue to go lower and lower, you'll notice a correlation between decreasing body size/mass and increasing population density.

The image below shows a biomass pyramid and a pyramid of numbers for two communities.
http://bodell.mtchs.org/OnlineBio/BIOCD/text/chapter36/concept36.2.html

2

Answer:

Anthropogenic in terms of climate change refers to the impact humans have had on climate change, primarily through emissions of greenhouse gasses.

Explanation:

Greenhouses gasses such as carbon dioxide #("CO"_2)# or methane #("CH"_4)# can be produced naturally in the environment through things like volcanoes or other geothermal sources. Throughout history, greenhouse gas concentrations have risen and fallen significantly over long periods of time.

The difference nowadays is that greenhouse gas emissions are increasing at a rate far beyond any sort of natural fluctuations. We know this by observing historical proxy data through things like ice core sampling, which allows us to compare historical data such as #"CO"_2# concentrations with modern #"CO"_2# levels.

So "anthropogenic climate change" would refer to climate change induced or at least significantly enhanced by human activity, such as industrialization.

1

Answer:

Here they are:

Explanation:

Denitrification: A biochemical process in which nitrates are reduced to ammonia or nitrogen gas (in the atmosphere the most abundant gas) by bacterial activity

Nitrogen fixation: The process of converting inorganic, molecular nitrogen in the atmosphere to ammonia or nitrate.

Lightning: Lightning oxidizes nitrogen, producing nitric oxide. In nature, essentially all other conversions of molecular nitrogen to biologically useful forms are conducted by bacteria.

Bacteria: Unicellular or filamentous microorganisms lacking chlorophyll, vital to pollution control because they occur in decaying (decomposing) matter in air, on the land, and in the oceans, and assist in the decaying process. An image of them attached below.

Nitrates: #NO_3# Nitrate is an inorganic compound composed of one atom of nitrogen (N) and three atoms of oxygen (O); the chemical symbol for nitrate is #NO_3#. Nitrate is not normally dangerous for the health unless it is reduced to nitrite (#NO_2#).

Read more: https://www.lenntech.com/processes/nitrates/nitrates/nitrate.htm#ixzz4v5yJ2L5D

Sciencephoto.com

1

Answer:

While human population rises, pressure on natural resources (such as forests) increases too.

Explanation:

Deforestation is related to human population growth that leads to ever increasing food production and animal husbandry as well as mining activities, road construction, urban sprawl etc.

Forests are important areas for carbon dioxide removal since photosynthetic plants need carbon dioxide to form sugar (glucose) and oxygen. Plants are a natural part of the carbon cycle and store CO2. If we cut trees down, they no longer remove CO2 from the atmosphere and store it.

https://eo.ucar.edu/kids/green/cycles6.htm

Human activities are limitless. We construct industrial plants, open pristine areas to mining, timber production, firewood production, road construction, urbanization, etc. The easiest way to do such activities is to remove forest cover. In some cases, nobody owns the forest: It belongs to all people though but there is no private person or group claiming ownership of forests. Even when someone does own the forest, companies are willing to spend lots of money to buy that forest and then clear it for development.

Over the past 100 years or 50 years, there is a huge drop in forest areas because humans do not care about importance of forests or do not recycle wastes. Deforestation has been occurring at a fast rate right now triggering global climate change, erosion, loss of lives and properties, etc.

1

Answer:

Seasons do not greatly affect underground water sources.

Explanation:

Underground springs that bring melted snow water underground to a surface source are cold even in the middle of summer. The ground insulates the water that entered the aquifer at cold high altitudes keeping it cold regardless of air temperatures.
https://www.intechopen.com/books/updates-in-volcanology-new-advances-in-understanding-volcanic-systems/volcanic-natural-resources-and-volcanic-landscape-protection-an-overview

Underground springs, known as hot springs, get their heat by contact with the heated magma underneath the earth's surface. This hot springs will be close to boiling hot even in the middle of winter when there is snow on the ground.

The temperature of underground water sources depends on the source of the water not the air temperatures.

2

Answer:

Most of this water is salt water and usable freshwater is much more rare. Increased demands and climate change are predicted to increase scarcity.

Explanation:

The Oceans cover vast areas of the globe but the salt water in these oceans is not useable for either drinking or irrigation. There are many fresh water lakes, notably the Great Lakes of America and Canada, the water in these lakes must be filtered and cleaned before the water can be used for human consumption.

Many rivers are used not only for drinking and irrigation but also for the disposal of waste products. The human waste is dumped into the rivers making the water downstream unusable until it has been treated.

There is a limit amount of usable fresh water. Much of the water has
been polluted and will become more polluted. At the same time the human population of the world is increasing, increasing the need for fresh water. The scarcity of fresh water will only increase in intensity as the demand for fresh water increases.

The image below shows water stress by country:
http://www.wri.org/blog/2013/12/world’s-36-most-water-stressed-countries

Prediction of future water scarcity:
http://www.wri.org/blog/2015/08/ranking-world’s-most-water-stressed-countries-2040
Changes in temperature , precipitation patterns (both due to climate change), and increase in demand are all drivers behind projected increased scarcity.