Ecology Flashcards
What is an ecosystem
An ecosystem is the interaction of a community of living organisms (biotic) with the non-living (abiotic) parts of their environment
Importance of interdependence and competition in a community
To survive and reproduce, organisms require a supply of materials from their surroundings and from the other living organisms there.
Plants in a community or habitat often compete with each other for light and space, and for water and mineral ions from the soil. Animals often compete with each other for food, mates and territory.
What is interdependence
Within a community each species depends on other species for food, shelter, pollination, seed dispersal etc. If one species is removed it can affect the whole community
What is a stable community
one where all the species and environmental factors are in balance so that population sizes remain fairly constant
Abiotic factors
light intensity
temperature
moisture levels
soil pH and mineral content
wind intensity and direction
carbon dioxide levels for plants
oxygen levels for aquatic animals
Biotic factors
availability of food
A new predators arriving
new pathogens
one species outcompeting another so the numbers are no longer sufficient to breed
Adaptations
Organisms have features (adaptations) that enable them to survive in the conditions in which they normally live. These adaptations may be structural, behavioural or functional
Structural adaptation
Features in an organisms body structure
Eg shape or color
Artic foxes have white hair, so they can camouflage in the snow which helps them Avoid predators. And sneak up and prey
Whales have thick layer of bluffer and low surface area to volume issue to help retain heat
Camels have thin layer of fats and large surface area to volume ratio to help lose heat
Behavioural adaptation
Many species migrate to warmer climates during the winter of problems of living in cold conditions
Functional adaptation
Inside the organisms body
Some organisms live in environments that are very extreme, such as at high temperature, pressure, or salt concentration. These organisms
are called extremophiles. Bacteria living in deep sea vents are extremophiles.
What are photosynthetic
photosynthetic organisms are the
producers of biomass for life on Earth.
Carbon cycle
The carbon cycle returns carbon from organisms to the atmosphere as carbon dioxide to be used by plants in photosynthesis
Water cycle
The water cycle provides fresh water for plants and animals on land before draining into the seas. Water is continuously evaporated and precipitated.
Three environmental changes that affect the distribution of organisms
Temperature
Availability of water
Composition of atmospheric gases
Environmental changes
Temperature
For example, the distribution of bird species in Germany is changing because of the rise in the average temperature
Environmental changes
 atmospheric gases
The distribution of some species change in areas, where there is more air pollution
Atmosphere changes
Availability of water
The distribution or some animals and plants species in the Chop exchange between the wet and dry season
Formula for rate
Rate - 1000/ time
Factors affect rate of decay
Temperature-warmer temperatures make things decompose quicker because they increase series which enzymes involved in decomposition work
Oxygen availability -many organisms need oxygen to respire
water availability- decay takes place faster in moist environments because the organisms involved in decayed water to carry out biological processes
Number of decay organisms -the more microorganisms that are the faster decomposition happens
What is biodiversity?
Biodiversity is the variation of different species of organisms on earth or within an ecosystem
Pollution
Pollution can occur:
in water, from sewage, fertiliser or toxic chemicals
in air, from smoke and acidic gases
on land, from landfill and from toxic chemicals.
Pollution kills plants and animals which can reduce biodiversity
What does biodiversity do
Ensures stability of ecosystems by reducing the dependence of one species on another for food, shelter, and maintenance of the physical environment
How do humans affect land use
Humans reduce the amount of land available for other animals and plants by building farming, dumping, waste and quarrying
Peat bogs
Books are an area of land that are acidic and water looked plants that live in both don’t fully decay when they die because there isn’t enough oxygen
Did you structure of bogs to produce guiding compost, reduces area of this habitat, which means that the variety of different plants and Mars and microorganism that lives there are also reduced
The decay of Peat releases carbon dioxide into the atmosphere
Deforestation
Deforestation is the act of cutting down forest
Reasons for deforestation include
Growing crops for biofuels
Providing land for cattle and Rice fields
Problems with deforestation
Less co2 is taking in
More carbon dioxide in the atmosphere
Less biodiversity
Consequences of global warming
Are you diversity will be reduced which would lead to extinction of certain species
Temperature rises causing sewer to expand an ice melt, which would cause the levels to raise, and that would lead to flooding and lead toloss of habitats
The distribution of many wild animals and plants species may change as temperature increases and the amount of rain changes in different areas
Global warming
The Earth is gradually hitting up because of the increase level in greenhouse gases
Levels of Karen, dioxide and missing in the atmosphere are increasing, which contributes to global warming
Programs put in place to reduce the negative effects of humans on ecosystem and biodiversity 
breeding programmes for endangered species
protection and regeneration of rare habitats
reintroduction of field margins and hedgerows in agricultural areas where farmers grow only one type of crop
• reduction of deforestation and carbon dioxide emissions by some governments
• recycling resources rather than dumping waste in landfill
Positive and negative human interactions in the ecosystem
Protecting biodiversity cost money
Protecting biodiversity may come at the cost to local peoples live, for instance, the people who are paid to cut down, trees may lose their jobs to preserve the biodiversity
Certain organisms are seen as pest by farmers, and I killed to protect the crops, which would result in the food chain and biodiversity being affected
The differences between the tropic levels of organisms within a ecosystem
Level 1: Plants and algae make their own food and are called producers.
Level 2: Herbivores eat plants/algae and are called primary consumers.
Level 3: Carnivores that eat herbivores are called secondary consumers.
Level 4: Carnivores that eat other carnivores are called tertiary consumers.
Apex predators are carnivores with no predators
Decomposes
Decomposers break down dead plant and animal matter by secreting enzymes into the environment. Small soluble food molecules then diffuse into the microorganism
Reasons for loss of biomass
Not all the ingested material is absorption is egested as faeces
Some absorbed material is lost as waste such as carbon dioxide and
water and water and urea in urine
What percent of biomass from each tropic is transferred to the level above it
10%
Formula for efficiency
Biomass transferred to the next level \
Biomass available at the previous level
X100
What is food security
have enough food to feed a population
Biological factors affecting food security
the increasing birth rate has threatened food security in some countries
changing diets in developed countries means scarce food resources are transported around the world
new pests and pathogens that affect farming
environmental changes that affect food production, such as widespread famine occurring in some countries if rains fail
the cost of agricultural inputs
conflicts that have arisen in some parts of the world which affect the availability of water or food.
Farming techniques
The efficiency of food production can be improved by restricting en transfer from food animals to the environment. This can be done by limiting their movement and by controlling the temperature of their surroundings
Substance, fishery
Fish stock in the ocean is declining. This is important to maintain fish stocks at the level where breathing continues or certain species may disappear altogether in some areas.
Fishing quarters, this is when there is a limit on the number and size of fishes that can be cut in certain areas to prevent overfishing
Net size, a limit on the size of fishing nets to reduce the number of unwanted or discarded fishes
Mycoprotein
The fungus Fusarium is useful for producing mycoprotein, a protein-rich ood suitable for vegetarians. The fungus is grown on glucose syrup, in aerobic conditions, and the biomass is harvested and purified.
GM crops
Genetically modified bacterium produces human insulin when have acid and purified. This can be used to treat people with diabetes.
Pros of b biotechnology
Produces crops that are resistant to pest, improving cropyields
Clubs can be genetically modified to grow better in drought conditions
Cups can be modified to improve more nutritional value
Cons of biotechnology
People argues that poverty is a bigger problem than availability of food
The main problem for in-availability of crops is poor soil so even if GM crops were used, they wouldn’t survive
Some fear Taft countries may come to dependence on GM crop companies 
