20. Human Influences Flashcards
(19 cards)
How have humans increased food production
A) Agricultural machinary-to use larger areas of land and improve efficiency
B) chemical fertillisers- to improve yield
C) insecticides- to improve field and quality
D) herbicides -to reduce competition with weeds
E) selective breeding -to improve production by crop plants and livestock
What is meant by monoculture of crop plants and what are the advantages and disadvantages
Cultivation of a single crop species on a specific agricultural land continuously
Advantages
Easier to mange
More efficient
Promotes agricultural technology
Higher earning
Disadvantage
Reduced ecosystem diversity
Increased pest issues
Problems with insecticides
Intensive livestock, its advantages and disadvantages
Rearing and management of animals for various purposes:,
Advantages
helps the economy and agricultural industry
Provides food security
Easier spread of disease
Welfare issues of livestock
Describe biodiversity
A number of different species that live in an area
Reasons for habitat destruction
1-increased area for housing, crop plants production and livestock production
2- extraction of natural resources
S- freshwater and marine pollution
Food web E food chain
Altering food weband food chain can have a negative impact on the habitat
.
Explain the undesirable affects of deforestation
- reducing biodiversity - deforestation leads to the loss of diverse plants and animal species that depend on the forest ecosystem for their survival
- Extinction- deforestation can research in the extinction of species that are unable to adapt or find alternative habitats
- Loss of soil no roots are present to hold the soil together, resulting in depletion and decreased fertility
4.flooding-leads to increased surface runoff, soil erosion and en elevated risk of flooding in surrounding areas - increased CO2 in atmosphere- trees absorb CO2 through photosynthesis. deforestation will lead to a higher level of greenhouse gases which contribute to global warming and climate change.
Describe the effects of untreated sewage and excess fertilliser on aquatic ecosystems.
When fertiliser and sewage enter the marine environments,”dead zones” form where there isn’t enough oxygen for life to thrive this is called eutrophication
Explain the process of eutrophication of water
When sewage a fertilisers enter marine environment
A there is an increased availability of nitrate and other ions
Be this leads to an increase growth of production producers
C increase decomposition after the death of producers next time
D increase aerobic respiration by decomposers
E reduction dissolved oxygen
F death of organisms requiring dissolved oxygen in water
Eutrophication of water occurs due to an increased availability of nitrates and other ions which promote excessive growth of producers like algae . When these producers die they are decomposed by micro organisms leading to a significant increase in aerobic respiration this process deplete the dissolved oxygen in the water creating oxygen deficient conditions as a result organisms that rely on dissolved organisms such as fish die for disrupting the aquatic ecosystem.
Describe the effects of non-biodegradable plastics in aquatic and terrestrial land
Aquatic ecosystem
Pollution-harms marine life
Habitat destruction - animals get trapped or eat plastics, plastics can also
Disrupt their homes
Contamination-plastic release harmful chemical polluting the water and harming the aquatic ecosystem
Terrestrial land
Soil pollution-plastic waste in the soil contaminates LANd affecting plant and nutrient cycle
Wildlife impacts- animals can be harmed by encountering plastic wastes
Spread of microplastic - plastics break down into tiny particles that can contaminate soil and affect wildlife
Describe the sources and effects of air pollution
Sources of methane are livestock -gasses released by animals or land fills - trash breaking down without air produces methane
Sources of carbon dioxide are burning fossil fuels for energy and other industrial processes
These gasses trap heat in the atmosphere intensifying, the greenhouse effects leading to global warming and climate change
Effect of air pollution
Altered weather pattern, rising sea levels- move frequent and severe weather events
Describe sustainable resources
Resourced produced as rapidly as it’s removed from the environment so it doesn’t run out.
Explain now forest can be conserved
Education - spreading awareness.
Protected areas - deforestation is limited.
Quotas - deciding on a specific amount of trees that can be cut.
Replanting - planting new trees to replace the ones that are used so forest stays healthy
Explain how fish stocks can be conserved
Education# spreading importance and awareness.
Closed seasons - fishing is off limit for certain time so fishes can grow and reproduce.
Protected areas- zones where fishing is off limit.
Quotas -number of fish allowed to be caught so over fishing doesn’t take place.
Controlled net type and mesh size Let small fish escape and catches only what’s needed
Reasons of organisms becoming endangered or extinct
Climate change
Habitat destruction
Over hunting
Over harvesting
Pollution
Introduced species
Describe how endangered species can be conserved
monitoring and protecting species and habitats.
Keeping close watch to make sure they stay safe and healthy
Education
Importance and how to help protect them.
Captive breeding programs
Taking care of endangered species in special places helping them have babies and releasing them back into the wild
Seed banks
Storing seeds of endangered plants so they can be grown again if they’re extinct
Describe the reasons for conservation programs
maintaining or increasing biodiversity
reducing extinction
protecting vulnerable ecosystem
maintaining ecosystem function
explain artificial insemination and in Vitro fertilisation
Artificial insemination
In captive breeding scientist help animals reproduce by collecting sperm from a male and inserting into a females body to fertilise her eggs
IVF
Eggs are taken from a female and fertilised with sperm outside her body in a lab then the fertilised eggs are put back into the females body or a surrogate mother helping them to reproduce when natural breeding is difficult
IVF in captive breeding can also be used to make sure that endangered animals have babies with different genes which help keep the species healthier and give them a better chance to survive
Risk to species if population decreases
If population decreases the genetic variety of the species decrease which make them weaker against diseases and changes in the environment leading to a higher risk of extinction
