Aquatic Ecosystems
the three main roles in a food web and give one aquatic example of each
What are Producers make food via photosynthesis (e.g., phytoplankton), consumers eat others (e.g., fish), decomposers break down dead material (e.g., bacteria/fungi)?
This is the definition of salinity and its common measurement
What is concentration of dissolved salts; measured in ppt (parts per thousand)
These are two major differences between littoral zones and pelagic zones in the ocean or lakes
What is littoral is shallow and pelagic is deep and has many layers?
Two human activities that harm aquatic ecosystems
What is pollution (runoff, plastics), habitat destruction (dredging, development), overfishing.
This is a hypothesis
What is an if/then statement relying on one to two variables?
energy flows through trophic levels in this way and only transfers this amount of energy
What is bottom up flow of energy, ~10% transferred?
This is the definition of pH and the typical pH of an aquatic ecosystem
What is measure of acidity/basicity. Freshwater typical ~6.5–8.5. pH
These are the layers of the ocean
What are Epipelagic (sunlight), Mesopelagic (twilight), Bathypelagic (midnight), Abyssopelagic (abyssal), and Hadalpelagic (trench) zones?
This is biomagnification and a common pollutant that biomagnifies
What is the increasing concentration of persistent pollutants up the trophic levels, for example, mercury or DDT?
These are three tools to measure water quality
probe (DO meter) — dissolved oxygen; pH meter — acidity; graduated cylinder/volumetric flask — precise volume measurements for chemical tests.
decomposers interact to cycle nutrients in a pond ecosystem in this way
What is decomposition and recycling?
These are three factors that affect dissolved oxygen in water
What is temperature, oxygen demand, and currents?
This is the definition of an estuary
What is mix of fresh and salt water near river mouth leading to high nutrient input and productivity?
One local consequence of overfishing
What is population collapse, altered food webs?
Salinity affects the survival of a common estuary in this way
What is survival rates?
A food chain or food web is more realistic to describe an estuary
What is a food web?
estuaries have many overlapping feeding links so food web is more realistic.
Temperature and salinity influence density in this way causing stratification
What is colder, saltier water is denser limiting mixing?
Major physical and biological characterisitcs of coral reefs and kelp forests
What is Coral reefs: warm, clear, tropical, calcium carbonate builders (corals/zooxanthellae). Kelp forests: temperate, cooler, dominated by large brown algae (kelp) attached to substrate?
Coastal development can alter natural shorelines in this way
What is increased erosion, interrupt sediment transport, and destroy wetlands? Nature-based solution: living shorelines (planting marshes, using natural materials)?
Two limitaions of models in aquatic science
What is scale differences (small tanks can't reproduce ocean scale), simplified boundary conditions (missing currents/biota), material limitations (model sensors/parameters).
Given a simplified aquatic food web (phytoplankton → zooplankton → small fish → larger fish → osprey), these are the ecological effects of removing zooplankton
What is bottom up tophic colapse?
Removing zooplankton → phytoplankton bloom (less grazing) → oxygen swings/eutrophication → fewer small fish → ripple effects to osprey.
This is the definition of eutrophication, and a method to reduce runoff
What is causing algal blooms and reducing fertilizer?
These are major abiotic factors leading to gradients across the continental shelf
lower salinity, higher turbidity, more freshwater species → moving offshore salinity increases, turbidity decreases, light increases → marine species dominate.
This is a way to monitor the health of a freshwater stream
What is monitoring temperature (thermal stress, DO influence), dissolved oxygen (ecosystem health), nitrates/phosphates (eutrophication risk)?
You can monitor/adjust aquatic ecosystems and adaptations this way
What is conducting an experiment?