Ecology question help pls?

Question

(a) Which type of organisms remove
1. carbon dioxide frm the atmosphere
one of my answers is : Plants,
But i don't have an idea of the other organisms

2. nitrogen frm the atmosphere
one of my answers is : Rhizobium Bacteria
But what other organisms?

(b) By which processes do microorganisms return

1. carbon dioxide to the atmosphere.
my answers are; respiration, decomposition
is fossilisation correct? i mean when the fuel is burnt, CO2 is returned to atmos

2. nitrogen to the atmosphere.
one of my answers is: denitrification
R there other processes?


(c) What are the main human impacts on
1. carbon cycle
2. nitrogen cycle


Thanks

Answer 1

All the answers r correct!!!

Answer 2

a1. remove carbon dioxide from the atmosphere
As a group, these are called producers or autotrophs.
Examples: plants, algae, cyanobacteria

a2. remove nitrogen from the atmosphere
nitrogen-fixing bacteria such as Nostoc, Rhizobium, Azotobacter, Rhodobacter, Klebsiella, Clostridium pasteurianum
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/N/NitrogenFixation.html
http://www.science.siu.edu/microbiology/micr425/425Notes/12-NitrFix.html

b1. Since the question asks which processes microorganisms use to do these things, the answer to this question should be cellular respiration. Microorganisms don't carry on burning or fossilization, so those can't be answers.

b2. Microbes return nitrogen to the air by denitrification.

c1. Human impacts on the carbon cycle include:
-- burning fossil fuels which returns ancient carbon dioxide to atmosphere after it's been out of the cycle for a long time
-- burning forests which puts carbon dioxide into the air and which takes away trees which would remove carbon dioxide
-- planting trees and other vegetation which increases the amount of plant matter to take carbon dioxide out of the air

c2. Human impacts on the nitrogen cycle include:
-- purposely planting legume-type cover crops to replenish nitrogen in the soil
-- using artificial processes to make nitrogen fertilizers (ammonia), putting additional nitrogen into the air. In fact, the denitrifying bacteria are not quite keeping up with the amount of additional nitrogen we put into the ground
-- putting excess nitrogen into surface water systems causing algae blooms and eutrophication
-- overfarming some areas, taking more nitrogen out of the soil than is being replaced
-- closing up organic wastes in landfills instead of allowing them to compost and decompose

Answer 3

I was going to give you some answers, but it looks like Ecolink has covered all the bases!

Have fun with your ecology study!

Answer 4

Good job they are all look correct to me

Answer 5

you are right. go ahead.