Topic 9: Ecosystems and Material Cycles Flashcards
What are abiotic factors?
The non-living aspects of an ecosystem, e.g. temperature, light intensity, moisture and pollutants.
What is a belt transect?
A line along a sampled area upon which quadrats are placed at intervals to determine the abundance and distribution of organisms in an ecosystem.
What is biodiversity?
The variety of living organisms in an ecosystem.
What is biofuel?
A renewable energy source produced from biomass.
What is biomass?
The total mass of organic material, measured in a specific area over a set period.
What are biotic factors?
The living components of an ecosystem, e.g. food availability, competition, predators and other species.
What is blackspot fungus?
An indicator species that is found on rose leaves. It is sensitive to the concentration of sulfur dioxide in the atmosphere so its presence indicates clean air.
What is a blood worm?
A type of indicator species that is adapted to live in water with high levels of pollution.
What is a captive breeding program?
The breeding of endangered animals in enclosures (such as zoos) to increase population numbers and preserve biodiversity.
What is the carbon cycle?
The cycle through which carbon (in the form of carbon dioxide) moves between living organisms and the environment. It involves respiration, photosynthesis and combustion.
What is a community in ecology?
All of the populations of different species living together in a habitat.
What is competition in an ecosystem?
When different organisms compete for the same resources (e.g. light, water, mates, territory) in an ecosystem.
What is compost?
Dead and decaying organic matter, commonly used as a fertiliser.
What is conservation?
The maintenance of ecosystems and biodiversity by humans in order to preserve the Earth’s resources.
What is crop rotation?
The practice of growing different crops each year in a cycle. This replenishes nutrients that may have been depleted by the previous crop.
What are decomposers?
Organisms that release enzymes which catalyse the breakdown of dead plant and animal material into simpler organic matter.
What is decomposition?
The breakdown of dead materials into simpler organic matter.
What are denitrifying bacteria?
Anaerobic microorganisms (found in waterlogged soils) responsible for the conversion of nitrate ions to nitrogen gas.
What is desalination?
A process that removes salts from saline water to produce potable water.
What is an ecosystem?
The community of organisms (biotic) and non-living (abiotic) components of an area and their interactions.
What is the efficiency of biomass transfer?
The efficiency of biomass transfer between trophic levels is calculated using:
What is the efficiency of energy transfer?
The efficiency of energy transfer between trophic levels is calculated using:
What is eutrophication?
The process in which pollution by nitrogen-containing fertilisers results in algal blooms and subsequent oxygen level reduction in bodies of water.
What are fertilisers?
Natural or artificial materials that are added to soils to provide essential nutrients and improve plant growth.
What is fish farming?
The breeding of fish commercially in enclosures for food to combat overfishing.
What is a food chain?
Describes the feeding relationships between organisms and the resultant stages of biomass transfer.
What is food security?
Ensuring that populations have access to adequate amounts of safe and nutritious food.
What is freshwater shrimp?
A type of indicator species sensitive to dissolved oxygen concentrations and only found in clean water.
What is an indicator species?
A species whose presence or absence in an environment provides an indication of environmental conditions, e.g. pollution levels.
What is interdependence in ecology?
The dependence of different organisms on each other for survival, e.g. plants depend on pollinators, herbivores depend on plants.
What is mutualism?
The interaction between two organisms where both benefit as a result of their relationship.
What are nitrifying bacteria?
Microorganisms found in the soil responsible for the conversion of ammonium ions into nitrite and then nitrate ions.
What is the nitrogen cycle?
The cycle through which nitrogen moves between living organisms and the environment, involving four types of bacteria.
What is nitrogen fixation?
The conversion of atmospheric nitrogen gas into ammonia by nitrogen-fixing bacteria in the soil or root nodules of legumes.
What are nitrogen-fixing bacteria?
Microorganisms responsible for the conversion of atmospheric nitrogen gas into nitrogen-containing compounds.
What are non-indigenous species?
A foreign species that does not naturally occur in an area. They may be introduced deliberately or accidentally.
What is parasitism?
The interaction between two organisms where only one organism, the parasite, benefits whilst the host does not.
What is pollution?
Contamination or destruction of the natural environment due to human intervention.
What is a population in ecology?
All organisms of the same species living with one another in a habitat.
What is potable water?
Water that is safe to drink.
What are predators?
Consumers that prey on and eat other animals.
What is prey?
Animals that are eaten by predators.
What is a pyramid of biomass?
A table of the dry mass of living material at each trophic level of a food chain.
What is a quadrat?
A square grid of known area used in sampling to determine the abundance and distribution of organisms in an ecosystem.
What is reforestation?
The replanting of forests in an effort to restore biodiversity.
What is reverse osmosis?
A method of desalination that uses a partially permeable membrane to remove impurities from drinking water.
What is a seed bank?
A storage of viable seeds to protect biodiversity.
What is a sludgeworm?
A type of indicator species adapted to live in water with high levels of pollution.
What are stonefly larvae?
A type of indicator species sensitive to dissolved oxygen concentrations and only found in clean water.
What does sustainable mean?
The ability to maintain something for future generations.
What is thermal desalination?
A method of desalination that uses heat to separate pure water from salts in salt water.
What is a trophic level?
The position of an organism in a food chain.
What is the water cycle?
The cycle through which water moves between living organisms and the environment.
