BRAINCAKEHuman Influence on Ecosystems
Revision notes for Human Influence on Ecosystems in Edexcel Biology (9BI0). Read the start of any lesson here, then sign in free for the whole lesson, the R.E.C.I.P.E. recall steps and the quiz.
- Human Population ExplosionFor most of history the human population grew slowly, held back by famine, disease and high infant mortality.
- Climate ChangeWeather is the state of the atmosphere at a given place and time: temperature, rainfall, wind and cloud.
- Depletion of Biological ResourcesA biological resource is any living thing, or product of one, that humans use: timber, fish, crops, medicines, fibres, and ecosystem services such…
- Loss of BiodiversityBiodiversity is the variety of life in an area.
- The Burden of ProofThe burden of proof is the responsibility to provide evidence for a claim.
- Evaluating StudiesWhen you read a study, for example one claiming a link between rising temperature and a change in a species, you need to judge how far its…
- Greenhouse EffectThe greenhouse effect is a natural process that keeps the Earth's surface warm enough for life.
- Evidence for the Global Temperature IncreaseSeveral independent types of evidence show that the Earth is warming.
- Analysis of Ice CoresThe ice sheets of Antarctica and Greenland have built up from snow over hundreds of thousands of years.
- Data ReliabilityClimate data come from many sources, and each has limitations that affect how reliable it is.
- MethaneMethane (CH4) is the second most important greenhouse gas produced by human activity, after carbon dioxide.
- Correlation or CausationA correlation is a relationship between two variables: as one changes, so does the other.
- Models of Global WarmingA climate model is a computer program that uses mathematical equations to represent the processes controlling climate: energy from the Sun, the…
- Effects of Climate ChangeA rise in mean global temperature does not simply make everywhere a little warmer.
- Risk of FloodingGlobal warming increases the risk of flooding in two ways: rising sea levels and heavier rainfall.
- The Effect on OrganismsTemperature affects living organisms mainly through its effect on enzymes, which control every metabolic reaction.
- Changes in Species DistributionThe distribution of a species is where it lives.
- Farming: Depletion of ResourcesFeeding a growing population requires more food from each hectare and more land for farming.
- Fishing: Depletion of ResourcesFish are a renewable resource, but only if enough adults are left to breed and replace those caught.
- Anthropogenic Changes in the OceanThe oceans are affected by human activity in several ways.
- Problems with ConservationConservation aims to protect species and habitats, but it often faces practical, economic and ethical problems.
- Fish Farming and AquacultureAquaculture is the farming of aquatic organisms such as fish, shellfish and seaweed.
- Endangered SpeciesAn endangered species is one at high risk of becoming extinct in the wild in the near future.
- ExtinctionA species is extinct when the last individual has died.
- Human Causes of ExtinctionMost extinctions today are caused, directly or indirectly, by human activity.
- Conserving BiodiversityConservation methods are divided into two types.
- CITESCITES is the Convention on International Trade in Endangered Species of Wild Fauna and Flora.
- CITES SuccessesCITES has helped several species recover, especially where controls on trade were combined with protection on the ground.
- Limitations of CITESCITES has had successes, but it has important limitations.