Actual Science olympiad water quality

What is ecology?

The study of how organisms interact with one another and with their environment.

What are abiotic components?

Non-living components or physical factors such as soil, rainfall, sunlight, and temperatures.

What are biotic components?

Living components, which include other organisms.

What is an ecosystem?

A community plus abiotic factors.

What is a biosphere?

All ecosystems on Earth.

What are lotic ecosystems?

Ecosystems characterized by flowing water, such as streams and rivers.

What are lentic ecosystems?

Ecosystems characterized by still water, such as ponds and lakes.

What is a watershed?

An area of land where water from rain and melting snow drains downhill into a body of water.

What is homeostasis in ecology?

The delicate balance of physiological processes within organisms.

What are the properties of populations?

Patterns of distribution and density, and intra-specific competition.

What is the trophic structure of communities?

The organization of food chains, food webs, and trophic pyramids.

What is mutualism?

A type of species interaction where both species benefit.

What is commensalism?

A type of species interaction where one species benefits and the other is neither helped nor harmed.

What is parasitism?

A type of species interaction where one species benefits at the expense of another.

What is the energy flow in ecosystems?

Energy flows in one direction, from producers to consumers.

What are biogeochemical cycles?

Processes that recycle nutrients in ecosystems, such as the nitrogen and carbon cycles.

What is an ecological pyramid?

A graph representing trophic level numbers within an ecosystem.

What is the hydrologic cycle?

The cycle of water movement through the environment, including evaporation, condensation, and precipitation.

What are indicator species?

Species used to assess the quality of an environment, often based on their sensitivity to pollution.

What is taxa richness?

The diversity of macroinvertebrates found in water; higher diversity indicates better water quality.

What does pollution tolerance indicate?

The presence of pollution-sensitive organisms suggests better water quality.

What are aquatic nuisance plants?

Invasive species such as Purple Loosestrife and Eurasian Water Milfoil that disrupt aquatic ecosystems.

What are some examples of pollution-sensitive macroinvertebrates?

Caddisflies, mayflies, and stoneflies.

What is the role of decomposers in an ecosystem?

Decomposers consume dead and decaying matter, recycling nutrients back into the ecosystem.

What is community succession?

The process of change in species composition over time in an ecological community.

What is the significance of species abundance?

The number of individuals in a population; large numbers may indicate nutrient-rich water, while small numbers may indicate pollution.

What are the main zones of a lake?

Littoral, limnetic, and profundal zones.

What is the difference between closed and open communities?

Closed communities have sharp boundaries, while open communities lack clear boundaries.

What are the three main feeding groups in aquatic ecosystems?

Collectors, Shredders, Scrapers, and Predators.

What do Collectors feed on?

Dissolved organic matter, algae, feces, and plants.

Where do Shredders typically find their food?

In areas with fallen leaves and vegetation in water.

What is the primary food source for Scrapers?

Algae and diatoms scraped off rocks.

What type of organisms do Predators hunt?

Other organisms, including invertebrates and small fish.

What is a salinometer used for?

To test the salinity of saltwater.

What does BOD stand for?

Biochemical Oxygen Demand.

How does temperature affect dissolved oxygen levels in water?

Cold water holds more oxygen than warm water.

What pH level begins to affect crustaceans and some plankton species?

A pH level approaching 6.0.

What happens to fish populations when water pH drops below 5.0?

The water becomes largely devoid of fish.

What is turbidity a measure of?

The cloudiness of water due to suspended particles.

What is the acceptable range of dissolved oxygen in surface waters?

Between 5 and 15 ppm.

What can high levels of fecal coliform bacteria indicate?

The presence of fecal matter in the water.

What are phosphates necessary for?

Plant and animal growth.

What can excessive phosphates in water cause?

Algal blooms that deplete oxygen levels.

What forms of nitrogen are usable for aquatic plant growth?

Ammonia (NH3) and nitrates (NO3).

What are total solids in water composed of?

Suspended solids and dissolved solids.

What is the effect of low concentrations of total solids in water?

It can limit the growth of aquatic organisms.

What is the significance of measuring turbidity in water?

It affects light penetration for photosynthesis.

What are some human sources of phosphates entering waterways?

Fertilizers, pesticides, and wastewater.

What is the relationship between nitrates and algal blooms?

Excess nitrates can cause algal blooms, reducing oxygen levels.

What materials are needed to build a salinometer?

Soda straw, modeling clay, permanent marker, container, salt, and water.

What is the role of dissolved oxygen in aquatic ecosystems?

It is essential for the survival of aquatic life.

What does a high BOD indicate about water quality?

It suggests high levels of organic matter and potential pollution.

What is the impact of increased temperature on aquatic organisms?

It increases metabolic rates and sensitivity to disease.

How does pH affect aquatic ecosystems?

Changes in pH can lead to shifts in species composition and health.

What is turbidity measured in?

Nephelometric turbidity units (NTU).