BIOGEOCHEMICAL CYCLES Flashcards
1
Q
Biogeochemical Cycles
A
- The movement and transformation of chemical elements and compounds between living organisms, the atmosphere, and the Earth’s crust
2
Q
Biogeochemistry
A
- The study of the chemical, physical, geological, and biological processes and reactions that govern the composition natural environments
- The study of biogeochemical cycles
3
Q
Gaseous Cycle
A
- Atmosphere & ocean constitute major reservoirs of matter (nutrients)
- Carbon & nitrogen cycles
- Makes these cycles effective globally
- Atmospheric mixing, wind transport
4
Q
Sedimentary Cycle
A
- Soil and rocks (i.e., lithosphere) are the major reservoirs of matter (nutrients)
- Phosphorus cycle
- Atmosphere is a minor reservoir at most
5
Q
Hybrid Cycle
A
- Important reservoirs in the lithosphere as well as the atmosphere and ocean (and cycling between them)
- Sulfur cycle
6
Q
3 Types of Transfers in Carbon Cycle
A
- Transfer between biotic components: transfer of biomass between trophic levels
- Transfer from biotic to abiotic: Transfer of death of biotic organisms and subsequent decomposition
- Transfer between abiotic components: Transfer of runoff to aquatic ecosystems
7
Q
Nitrogen Fixation
A
- During lightning storms, nitrogen gas (N₂) is split and combined with oxygen to form nitrate (NO₃) or with hydrogen to form ammonia (NH₃), which then falls to the ground and can be used by plants.
8
Q
Atmospheric Fixation
A
- Refers to the natural process where nitrogen in the atmosphere is converted ammonia or nitrate through physical processes like lightning.
9
Q
Atmospheric Deposition
A
- Nitrogen and ammonium compounds are deposited from the atmosphere to the soil through rain, snow, dust, or from human activities or lightning. This adds nitrogen to ecosystems.
10
Q
Weathering
A
- Physical process (water, wind) that breaks rocks down
11
Q
Limiting Nutrient
A
- When a nutrient is found in low enough levels that it dictates the maximum rate of plant productivity
