Vertical Patterns and Temporal Trends Flashcards
What is the pelagic environment?
The pelagic environment is a three-dimensional space where zooplankton can be found throughout the water column, with abundance decreasing with depth.
What factors influence vertical distribution of zooplankton?
Key factors include temperature, food availability, light levels, and oxygen availability.
What is the Epipelagic Zone?
The Epipelagic Zone (0-200 m) is where most zooplankton are concentrated due to high food availability.
What characterizes the Mesopelagic Zone?
The Mesopelagic Zone (200-1000 m) is a transition zone with reduced light and food.
What is the Bathypelagic Zone?
The Bathypelagic Zone (>1000 m) is dark and nutrient-poor, but some species adapt by feeding on sinking organic matter.
What is a thermocline?
A thermocline is a layer where temperature rapidly decreases with depth, separating warm surface water from colder deep water.
What is a halocline?
A halocline is a layer with a sharp change in salinity.
What is a pycnocline?
A pycnocline is a zone of rapid density change, resulting from thermocline and halocline effects.
How does light penetration affect primary productivity?
Light penetration influences primary productivity, with phytoplankton thriving in the photic zone.
What is the role of food availability in zooplankton distribution?
Food availability, influenced by primary producers and water column stratification, affects zooplankton distribution.
How do biological interactions influence zooplankton distribution?
Predator-prey relationships shape vertical distribution patterns, influencing migration and aggregation behavior.
What physiological constraints affect zooplankton?
Oxygen availability is a limiting factor; some species adapt to hypoxic conditions by residing near oxygen minimum zones (OMZs).
Where is the highest abundance of zooplankton found?
Over 80% of zooplankton abundance is found in the upper 200 meters due to high food availability.
How does species diversity change with depth?
Species diversity is highest in the epipelagic and mesopelagic zones, declining with depth.
What is the biodiversity index (Shannon)?
H’ = biodiversity index (Shannon).
How can functional diversity be classified?
Functional diversity can be classified via functional groups, such as herbivores and carnivores.
What are the characteristics of estuarine vertical structure?
Estuaries exhibit complex circulation patterns due to interactions between freshwater input and tidal flow.
What are euryhaline and stenohaline species?
Euryhaline species tolerate a wide salinity range, while stenohaline species have narrow salinity tolerance.
What is diel tidal vertical migration (D-TVM)?
Diel tidal vertical migration (D-TVM) is a behavioral strategy some species use to maintain their position in estuarine environments.
What is Diel Vertical Migration (DVM)?
A key behaviour where zooplankton move up and down the water column over a 24-hour cycle.
Why does DVM occur?
- Predation avoidance
- Energy conservation
What is the predation avoidance strategy in DVM?
Zooplankton stay at depth during the day to avoid visual predators and ascend at night to feed.
What does the temperature-benefit hypothesis suggest?
Residing in cooler waters reduces metabolic rates, allowing more ingested energy to go towards growth instead of respiration.
What is the primary cue for DVM mechanisms?
Light as the primary cue.
