Lecture 20: Ecosystems: Aquatic nutrient regeneration & landscape ecology Flashcards
In aquatic systems, biochemical __________________ (all takes place in water)
processes are the same as on land
Main difference is that in aquatic systems, _________________ and __________________ sediment deposits.
- organic material sinks
- nutrients get stored in deep-water
Most nutrient regeneration in aquatic systems occurs in sediment deposits, but it is ____________ than regeneration in the soil of terrestrial systems
much slower
Aquatic sediment and terrestrial soils are _______________, but their roles in nutrient regeneration are _________________.
- superficially similar
- different in 2 key ways
differences in aquatic sediment and terrestrial soils
- Distance between regeneration and autotrophs
- Decomposition conditions
terrestrial soils - Distance between regeneration and autotrophs
Regeneration in soil takes place very close to the roots of plants.
aquatic sedimentation - distance between regeneration and autotrophs
Aquatic plants and algae inhabit the top (photic) water layers, far from nutrient regeneration in deep sediment.
terrestrial soils - decomposition conditions
Decomposition is aerobic and relatively quick in terrestrial soils.
aquatic sediment - decomposition conditions
- Decomposition is typically anaerobic in aquatic sediment
- The lack of oxygen slows the biochemical processes of regeneration.
_________________ when sediment is _____ from upper water layers, or if sediment nutrients are actively _____________.
- Productivity is only high
- not far
- redistributed
Primary _______________ in areas with strong _______________, providing active nutrient redistribution.
- productivity is also high
- upwelling currents
define landscape ecology
The study of the composition and spatial arrangement of habitats, both natural and anthropogenic, and how this influences ecological systems at all scales
how is landscape ecology a key link to
understanding global biodiversity
it has a major impact on biodiversity at regional and global scales
landscape ecology can be a discipline that bridges what
- ecosystems and the biosphere-level processes and patterns
- like global biodiversity
“Landscapes” can be thought of as a collection of___________________________________.
interacting habitat types within or across ecosystems
Landscapes are shaped by _____________, and ____________________.
- past and present
- natural and anthropogenic events
________________________________________, have changed rock and soil distribution, dramatically changed topology, and altered the size, shape and interactions between bodies of water
Volcanic eruptions, glacier movement, and continental drift
The long lasting influences of historical processes on present-day ecological processes are know as ____________ , and they can be natural or human legacy effects.
legacy effects
Legacy effects — the example of eskers
- When glaciers go away, you get really flat land
- Rivers are between glaciers and as the river flows, the sediment builds up
- When the glacier goes away – there is a small ‘mountain’ of sediment
Modern influences on landscapes
- Hurricanes
- Tornadoes
- Floods
- Mudslides
- Fires