biodiversity and ecosystems- CH18

biodiversity

variety of all the different species or organism on earth or within an ecosystem

high biodiversity is important to ensure

ecosystems are stable and reduces the dependence of species on others for food, shelter and maintenance of physical environment

impact of humans on ecosystems

humans reduce the amount of land available for other animals and plants

population

number of a species in an area

capacity

the max amount of a species that can fit and live somewhere

mortality rate

death rate in a time period

morbidity rate

disease infection rate in a time period

toxic chemicals, landfill, herbicides, pesticides, nuclear waste accidents

human land pollution

human water pollution

toxic chemicals, fertilisers, sewage

acid rain formation

fossil fuels contain sulphur impurities which react with oxygen when burnt and create **sulphur dioxide gas**. this gas can dissolve in rain water and from acid rain

the acidity of the water increases which can kill the animals and plants that live in them

effect of acid rain on lakes

smoke pollution

increases the number of particulates in the air which reflect sunlight so less hits earth’s surface. this can create a dimming effect leading to cooling earth’s surface and damages the lungs

smog

visibility reducing pollution that mixes smoke and fog

grow foods, cattle farming, grow crops to make biofuels

reasons for deforestation

deforestation increases amount of CO2 because

they store carbon for years, combustion releases CO2, dead vegetation respires releasing CO2

peat bogs

dense wetlands filled with partially decayed vegetation and plant matter that store huge amounts of carbon. it is being destroyed to burn for fuel

greenhouse gas

any gas that can absorb infrared ration and re-radiate it

climate change

global weather pattern changes driven by global warming

global warming

the sun emits energy and most is remitted, however greenhouse gases absorb some of it

habitats melt and can flood low lying areas destroying more habitats and reducing biodiversity

rising sea levels and loss of habitat

as climates get hotter or colder and seasons change so may the migration patterns which could have a negative effect due to dependency

changes in migration

conditions may become more favourable for other animals

changes in distribution

water availability, temperature and atmospheric gases

environmental changes

breeding programmes for endangered species

helps rare animals that don’t reproduce quickly or easily, but need to avoid inbreeding

landfill produces pollution and taxes on waste are being introduced to encourage composting

recycling resources

protection and regeneration of rare habitats

protect to allow regeneration in order to keep biodiversity

field margins and hedgerows

reducing these reduced the number of plants and insects decreasing soil fertility so they are being reintroduced

reduction of deforestation and CO2 emissions

some areas are wroking with local governments to adapt electrics and transportation

trophic levels

represent positions of organisms in a food chain

biomass

mass of material in living organisms

pyramid of biomass

shows the amount of biomass at each stage is less than in the previous, only 10% passed on as some is lost as faeces, during respiration and not all of the animal is eaten

wet is less reliable as it changes throughout the day so less reproducible and repeatable however dry involves killing the animal

wet vs dry biomass

apex predator

carnivores without any predators themselves

decomposers

break down dead organisms by secreting enzymes into their environment

increasing birth rate, changing diets, new pests and pathogens, environmental changes, conflicts, cost of agricultural inputs

factors affecting food security

cheaper and easy as the are close in proximity. they are fed high protein food to max growth and profit

advantages of fish farming

disease can spread and waste can pollute other environments

disadvantages of fish farming

fish farming

protects wild stocks and produces cheap protein

overfishing

restrictions have been put in place over conservation, fish size the size of holes in the net, and general quotas

Mycoprotein

type of fungus that is high protein and fast to make

30 degrees, glucose, oxygen for aerobic conditions and stable ph

conditions for mycoprotein