Unit 20 Flashcards
how have humans used agricultural machinery to produce more food
increases efficiency and larger areas of land is used
how have humans used chemical fertilizers to produce more food
increases crop yields
how have humans used insecticides
increases crop yields and food quality
why do humans use herbicides
reduces number of weeds
why do humans use selective breeding
improves production of livestock and crops
what is monoculture
one variety of crop is grown at a time
disadvantages of monoculture
reduced biodiversity in the area
diseases can spread easier which leads to more insecticides
soil is damaged since nutrients are used up and soil will erode
increased fertilizers and insecticides causes pollution
advantages of monoculture
allows farmers to use machinery and increases efficiency
easier to manage
takes advantage of certain weather conditions
advantages of intensive livestock production
produces high amounts of food for growing human population
efficiency increases while costs decrease
disadvantages of intensive livestock production
impacts the animals wellbeing and health
impacts the environment(pollution)
disease can spread quickly
what is biodiversity
the number of different species living in an area
what are reasons for habitat destruction
increased area for housing, crop production and livestock
extraction of natural resources
freshwater and marine pollution
how can humans have a negative impact on negative habitats
through altering food webs and food chains
what is deforestation
the cutting down of trees in forests
what can deforestation lead to
flooding
loss of soil
extinction of species
increase in carbon dioxide in the atmosphere
what is flooding(deforestation)
trees hold soil together and when theyre gone soil is washed away
what is loss of soil (deforestation)
when large areas are cleared, the protective layer of vegetation is lost
soil is then blown away by wind or rain
what is extinction (deforestation)
animals may be forced to migrate or stay in the area where they struggle to find food and shelter since the habitats are destroyed
what is carbon dioxide(deforestation)
with trees gone, photosynthesis cannot occur and carbon dioxide is not converted to carbohydrates
what is pollution
the release of any substance that has a toxic effect on the environment
what is the effect on untreated sewage and excess fertilizer in aquatic ecosystems
causes eutrophication and pollutes waterways that kills fish and plants while also endangering human life
what are the effects of non biodegradable plastic on aquatic ecosytems
cases suffocation and entanglement of marine wildlife and can cause starvation of fish
can also affect humans
what are the effects of non biodegradable plastic on terrestrial ecosystems
causes soil destruction and animal deaths
can also infect humans with harmful chemicals
how does air pollution affect the nevironment
leads to the greenhouse effect due to methane and carbon dioxide and climate change as the earth gets warmer
what is eutrophication of water
fertilizer leaks into waters
increases growth of producers
leads to increased decomposition and blocking of sunlight
reduced oxygen
death of organisms such as plants and marine life due to loss of oxygen
what is a sustainable resource
one which is produced as rapidly as its removed from the environment
what resources can be conserved and managed sustainably
forests and fish stocks
reasons for endangerment or extinction of organisms
climate change
habitat loss
hunting
overharvesting
pollution
introduction of new species
how can endangered species be conserved
monitoring of protected species and habitats
education
captive breeding programs
seed banks
how can forests be conserved
education
protected areas
quotas
replanting
how can fish stocks be conserved
education
closed seasons
protected areas
controlled net types and mesh size
quotas and monitoring
what are the reasons for conversation programmes
maintaning or increasing biodiversity
reducing extinction
protecting vulnerable ecosystems
maintaining ecosystem functions
what is artificial insemination and IVF used for in captive breeding programmes
increases populations of organisms and reduces endangered species
what are the risks to a species if population size decreases
reducing genetic variation in he species and leads to extinction
