module 4.2 Flashcards
COMMUNITY definition
all the living organisms, of a species, living in the same place at the same time (interacting populations)
SPECIES definition
a group of organisms with simmilar morphology and physiology. Can interbreed to produce fertile offspring
ECOSYSTEM definition
- a self contained system including all the living organisms and their environment interacting with each other (biotic and abiotic)
HABITAT definition
- a place where an organism lives
POPULATION definition
- a group of organisms of the same species, living in the same place at the same time, and able to interbreed with each other
whats biodiversity
biodiversity is a measure of all the different plant, animal, fungal and other microorganism species worldwide, the genes they contain and the ecosystems which they form a part - there are 3 levels of biodiversity.(the variety of living organisms in an area)
what are the 3 levels of biodiversity
- habitat biodiversity
- species biodiversity
- genetic biodiversity
what’s habitat biodiversity
the number of different habitats found in a region
what’s species biodiversity
the number of species in a given habitat/ ecosystem .( rainforest vs grass), there are two subsections…
- species richness= related to the number of species present
- species evenness= the relative abundance of individuals of each species
whats genetic biodiversity
the number of genetic variation in a species i.e, more alleles= more biodiversity
how do you measure species richness
- count the number of different species
- can sue the random quadrat technique
- no need to identify species
how do u measure species evenness
- plants= use random quadrats, count the number of each species or % cover
what is spearman’s rank
a statistical test used to determine whether the relationship between 2 variables is statistically significant. rs= spearman’s rank value
what does it mean if there is a negative rs= spearman’s rank value
a negative correlation
what does it mean if there is a positive rs= spearman’s rank value
a positive correlation
whats P value
a statistic that determines if an observation is significant. i.e very unlikely to be due to chance.
P<0.05= observation is significant
<5% chance the results were random
why do we measure biodiversity
- economic reasons ( to understand/ asses the impact of development on the environment.
- identify trends in extinction
- pure understanding of our existence.
why do you take random sampling
to avoid bias
what are the 3 types of non-random sampling
systematic, opportunistic, stratified
what is (non-random) systematic sampling
when samples are taken at fixed intervals, often along a line (which is called a transect)
what is (non-random) opportunistic sampling
when samples are chosen by the investigator. its used because its simple to carry out, but the data will be biased
what is (non-random) stratified sampling
when different areas in a habitat are identified and sampled separately in proportion to part of their habitat as a whole.
what 2 factors does the Simpsons index take into account
species evenness and species richness
what number is the Simpsons index of diversity always between
0 and 1
what happens if a population has low genetic biodiversity
it might get wiped out as they may not be able to adapt to change
give an example where genetic diversity might be low
isolated populations such as those bred in captivity
what are alleles
different versions of a gene
where are alleles of the same gene found
they are found at the same locus (point)
what does polymorphism describe
a locus that has two or more alleles
how do u calculate genetic diversity
proportion of polymorphic gene loci= number of polymorphic gene loci/ total number of loci
what are the 3 factors affecting global biodiversity
human population growth, increased use of monoculture in agriculture, climate change
why does human population growth lead to loss of biodiversity
human population growth has led to…
- habitat loss- due to human development
- over-exploitation-now a greater demand for resources
- urbanisation- cities and road developments can isolate species- unable to interbreed
- pollution- kill species or destroy habitats
why does increased use of monoculture in agriculture lead to loss of biodiversity
- habitats are lost due to clearing of land
- local and naturally occurring animals/plants are seen as pests and weeds so destroyed reducing species diversity
- traditional crops are lost because they don’t make enough money
why does climate change lead to loss of biodiversity
- most species need a particular climate to survive.
- change= area becomes uninhabitable
- could increase or decrease range of species
- species distribution may change due to migration
- if something cant migrate fast enough, biodiversity is reduced
what are the 3 reasons why maintaining biodiversity is important
- ecological reasons
- economic reasons
- aesthetic reasons
why is maintaining biodiversity is important for ecological reasons
1) to protect species including keystone species (many other species depend on this species)
- organisms are interdependent
- the loss of just one species can lead to… disruption of food chain, disruption of nutrient cycles
2) to maintain genetic resources
-genetic resources are any material from plants, animals or microorganisms containing genes which we find valuable
-genetic resources provide us with everyday products like;
food and drink, clothing, drugs, fuels, industrial materials
why is maintaining biodiversity is important for economic reasons
1) to reduce soil depletion
- monoculture is growing a single variety of a single crop
- continuous monoculture= planting the same crop in the same field without interruption
- continuous monoculture causes soil depletion
- the economic costs of soil depletion includes increased spending on fertilizers and decreased yields
why is maintaining biodiversity is important for aesthetic reasons
1) areas rich in biodiversity provide pleasant attractive landscapes
2) the more biodiversity, the more likely it is to attract visitors- has economic advantages
what does in situ conservation do
keeps species in their natural habitats
what does ex situ conservation do
removes species from their natural habitats (off site conservation)- normally the last resort
why is conservation important
to ensure the survival of endangered species
outline the methods of in situ conservation
1- establishing national parks or wildlife reserves- restricts urban development, farming or industrial development, also controlled fishing zones
2-controlling or preventing the introduction of species that threaten local biodiversity
3-protecting habitats so organisms can continue to thrive
4- promoting particular species e.g. protecting food sources
5- giving legal protection to endangered species, e.g. making it illegal to kill them
advantages and disadvantages of in situ conservation
+ both species and their habitat are conserved
+ larger populations can be protected and its less disruptive than removing organisms
+ changes of the population recovering are greater
- can be difficult to control factors that are threatening species
outline the methods of ex situ conservation
1) relocating an organism to a safer area
2) breeding organisms in captivity then reintroducing them into the wild when they are strong enough
3) botanic gardens= controlled environments which grow a variety of rare plants for purposes of conservation, research, display and education
advantages and disadvantages of ex situ conservation
+ used to protect individual animals in a controlled environment
+can be used to reintroduce a species that left an area
- only a small number of individuals can be cared for
- can be difficult and expensive to sustain and create the right environment
- may catch a disease from humans
-less successful than in situ
-many species cant breed successfully in captivity
-don’t adapt to their new environment when moved to a new location
what are the 2 international corporations that are important in species conservation
- Rio Convention on Biological Diversity (CBD)
- CITES Agreement
outline the aim of the international cooperation:
Rio Convention on Biological Diversity (CBD)
1) aims to develop international strategies on the conservation of biodiversity and how to use animal and plant resources in a sustainable way
2) the convention made it part of international law that conserving biodiversity is everyone’s responsibility
3) it also provides guidance to govs on how to conserve biodiversity
outline the aim of the international cooperation:
CITES Agreement
1) CITES (Convention of International Trade in Endangered Species) is an agreement designed to increase international cooperation in regulating trade in wild animal and plant specimens
2) The member countries all agreed to make it illegal to kill endangered species
3) helps conserve species by limiting trade through licencing, and by making it illegal to trade in products made from endangered animals
4) designed to raise awareness of threats to biodiversity through education
