20 net ecosystem production nep is always negative if

* 20) Net ecosystem production (NEP) is always negative if
(a) R
a
> GPP
(b) R
a
> GPP
(c) R
T
< NPP
(d) R
T
< GPP
* 21) Eutrophication (high rates of primary productivity in an aquatic community) usually occurs as a
result of
22) Aquatic primary productivity is unlikely to be limited by * 23) Marine primary productivity is most likely to be high

* 24) Addition of nutrients to aquatic ecosystems often stimulates primary production, causing the water
to become turbid due to high densities of phytoplankton. This process is known as
(a) net ecosystem production
(b) trophic efficiency
(c) eutrophication
(d) decomposition
* 25) Dead zones in coastal ecosystems 26) Which of the following is an important physical reservoir for the terrestrial nitrogen cycle?
* 27) Radiant energy is captured by plants and stored as
28) Inorganic nutrients are taken up by primary producers and
(a) converted to chemical energy
(b) converted to radiant energy
(c) used to build inorganic matter
(d) used to build organic matter
* 29) Nitrates (NO
3
- ) ions dissolved in the soil water of a garden would be