Environment

Correct answer: D

I is incorrect: Total rate of carbon fixation by producers → Gross primary productivity. It includes production subsequently used in plant respiration. II is correct: Phosphorus cycle's usual lack of a major gaseous phase → Sedimentary nutrient cycle. Rock weathering and sediment processes are especially important.

Correct answer: B

NPP equals GPP minus autotrophic respiration.

Correct answer: D

I is incorrect: Feeding position in an ecosystem → Trophic level. Producers occupy the first trophic level. II is incorrect: Loss of water vapour from plant surfaces → Transpiration. Stomata are a major route of water loss.

Correct answer: B

Net uptake distinguishes a sink from a source.

Correct answer: A

I is correct: Long-term storage of carbon in vegetation or soil → Carbon sequestration. It removes carbon from active atmospheric circulation for some period. II is correct: Total rate of carbon fixation by producers → Gross primary productivity. It includes production subsequently used in plant respiration.

Correct answer: D

Decomposers convert organic nitrogen into mineral forms.

Correct answer: C

I is correct: Phosphorus cycle's usual lack of a major gaseous phase → Sedimentary nutrient cycle. Rock weathering and sediment processes are especially important. II is incorrect: Producer biomass gain after respiration → Net primary productivity. NPP equals GPP minus autotrophic respiration.

Correct answer: D

Stomata are a major route of water loss.

Correct answer: B

I is incorrect: Conversion of ammonium to nitrite and nitrate → Nitrification. Specialised microorganisms oxidise reduced nitrogen. II is incorrect: Conversion of atmospheric nitrogen to biologically usable forms → Nitrogen fixation. Certain microbes and physical processes perform it.

Correct answer: C

It includes production subsequently used in plant respiration.

Correct answer: A

I is correct: Producer biomass gain after respiration → Net primary productivity. NPP equals GPP minus autotrophic respiration. II is incorrect: Feeding position in an ecosystem → Trophic level. Producers occupy the first trophic level.

Correct answer: D

It can contribute to groundwater recharge.

Correct answer: B

I is correct: Long-term storage of carbon in vegetation or soil → Carbon sequestration. It removes carbon from active atmospheric circulation for some period. II is incorrect: Organic matter from dead organisms → Detritus. Detrital food chains begin with this material.

Correct answer: C

Specialised microorganisms oxidise reduced nitrogen.

Correct answer: B

I is incorrect: Phosphorus cycle's usual lack of a major gaseous phase → Sedimentary nutrient cycle. Rock weathering and sediment processes are especially important. II is incorrect: Water entering the soil surface → Infiltration. Its rate depends on soil and surface conditions.

Correct answer: C

It links land-water loss with vegetation.

Correct answer: B

I is incorrect: Release of ammonium during decomposition of organic nitrogen → Ammonification. Decomposers convert organic nitrogen into mineral forms. II is correct: Conversion of atmospheric nitrogen to biologically usable forms → Nitrogen fixation. Certain microbes and physical processes perform it.

Correct answer: A

Detrital food chains begin with this material.

Correct answer: D

I is correct: Total rate of carbon fixation by producers → Gross primary productivity. It includes production subsequently used in plant respiration. II is incorrect: Water entering the soil surface → Infiltration. Its rate depends on soil and surface conditions.

Correct answer: C

I is incorrect: Water entering the soil surface → Infiltration. Its rate depends on soil and surface conditions. II is correct: Feeding position in an ecosystem → Trophic level. Producers occupy the first trophic level.

Correct answer: B

It returns nitrogen to the atmosphere, often in oxygen-poor conditions.

Correct answer: B

I is incorrect: Total rate of carbon fixation by producers → Gross primary productivity. It includes production subsequently used in plant respiration. II is correct: Combined evaporation and transpiration → Evapotranspiration. It links land-water loss with vegetation.

Correct answer: A

Its rate depends on soil and surface conditions.

Correct answer: C

I is correct: Conversion of nitrate to gaseous nitrogen forms → Denitrification. It returns nitrogen to the atmosphere, often in oxygen-poor conditions. II is incorrect: Water moving downward through soil → Percolation. It can contribute to groundwater recharge.

Correct answer: B

Producers occupy the first trophic level.