4.2.1 Biodiversity Flashcards
1
Q
define ecosystem
A
the interactions between all organisms, and their environment in a particular area
2
Q
define abiotic factor
A
the non-living physical and chemical factors in an ecosystem that affect a populations distribution and abundance
3
Q
define population
A
a group of organisms of the same species living in the same place at the same time who can interbreed
4
Q
define niche
A
the role of an organism within an ecosystem, the effects it has on other components of the ecosystem and the effects they have on it
5
Q
define biotic factor
A
an environmental factor caused by other living organisms that affect a populations distribution and abundance
6
Q
define community
A
the sum total of all living organisms of all species living in the same place at the same time
7
Q
define species
A
a group of organisms that are able to breed together to make fertile offspring and have the same morphology, anatomy physiology and behaviour
8
Q
define biodiversity
A
the variety of living organisms present in an area
9
Q
why is biodiversity important?
A
biodiversity is fundamental to sustainable life and is essential in maintaining a balanced ecosystem for all organisms due to interdependence
10
Q
what are the different levels of biodiversity?
A
-habitat biodiversity
-species biodiversity
-genetic biodiversity
11
Q
describe habitat biodiversity
A
the number of different habitats found within an area- each habitat can support multiple different species
12
Q
what are the two types of species biodiversity?
A
-species richness
-species evenness
13
Q
describe species richness
A
the number of different species found within an area
14
Q
describe species evenness
A
a comparison of the numbers of individuals of each species living in a community
15
Q
describe genetic biodiversity
A
the variety of genes that make up a species
16
Q
what are the impact of genes?
A
-many genes will be the same for individuals in a species
-different alleles increase the genetic biodiversity of a species
-greater genetic biodiversity within a species allows for better adaptation to a changing environment and is more likely to lead to individuals who are resistant to disease
17
Q
why do we need to measure biodiversity?
A
-provides a baseline for the diversity of an area
-allows the affect of any changes in the environment to be measured
-conservation
-to know what species are present
18
Q
what is the Environmental Impact Assessment (EIA)?
A
an assessment undertaken before a major project is carried out (e.g. a new road), to predict the positive and negative effects of a project on the biodiversity in that area
19
Q
what do EIA’s look at?
A
-environmental changes within ecosystems and habitats
-potential gains/losses in: the variety of species, the variety and abundance within in species, the space available for ecosystems and habitats, the physical connectedness between ecosystems and habitats
20
Q
why do rainforests matter?
A
-a constant supply of sunlight and water in rainforests has encouraged the proliferation of species
-the warmth and humidity below the canopy allow pathogens to abound
-they are the source of much food and other products such as Brazil nuts, bananas, rubber and resins
-rainforests store around half of Earth’s available fresh water
-it’s been estimated that the Amazon creates as much as 80% of its own rainfall
-rainforests are crucial in the Earth’s carbon cycle
-up to half of all the carbon stored in land based ecosystems resides in rainforests
21
Q
what is sampling?
A
sampling takes measurements of a limited number of organisms within a particular area
22
Q
what does sampling allow us to do?
A
-estimate the abundance of organisms
-measure a particular characteristic
-assess human impact on habitats and biodiversity
23
Q
why do we sample?
A
-to measure to biodiversity of a habitat
-observe all species present
-identify all species
-count how many individuals are in each species
24
Q
what are the different types of sampling?
A
-random sampling
-non random sampling
25
when is random sampling used?
areas with uniform or patchy distributions- this removes bias and ensure that the sample is representative
26
what are the characteristics of the process of random sampling?
-selects area/individuals by chance
-uses a grid and generates random coordinates
27
what are the types of non-random sampling?
-opportunistic sampling
-stratified sampling
-systematic sampling
28
when is opportunistic sampling used?
biologists use this method because it is easy
29
what are the characteristics of the process of opportunistic sampling?
-chooses samples that are conveniently available
-weakest form of sampling
30
when is stratified sampling used?
-to calculate populations for individual strata (sub-group) and the total population
-can produce precise results for the strata in each population
31
what are the characteristics of the process of stratified sampling?
-splits populations based on characteristics
-each strata is sampled
32
when is systematic sampling used?
to see changes in populations over a given stretch of habitat
33
what are the characteristics of the process of systematic sampling?
-sampling different areas within a habitat
-often uses a line or belt transect over an environmental gradient
34
what is a line transect?
lay tape measure down and count what it touches
35
what is a belt transect?
place quadrat at set intervals along transect
36
why is a sample never fully representative?
-sampling bias= selection process may be biased
-chance= organisms selected may not be representative of the whole population
37
how can sampling bias be reduced?
random sampling
38
how can chance be eliminated in sampling?
can be minimised by using a larger sample
39
what are the methods for plant sampling?
-frame quadrat
-point quadrat
40
what is a point quadrat?
count what touches the pole
41
what are the methods for animal sampling?
-mammal trapping
-pooter
-tree beating
-kick sampling
-pitfall traps
-sweep nets
-Tullgren funnels
-capture - mark- release- recapture
42
what does mammal trapping involve?
often pressure plated or motion censored
43
what are Tullgren funnels used for?
for different invertebrates found in soil
44
how do Tullgren funnels work?
-involves soil on a gauze
-light bulb above soil produces heat and causes insects to burrow down
-they fall down the funnel into a beaker
45
describe how capture-mark-release-recapture
1.capture as many animals as possible
2.mark each individual before releasing it back into the sample area-ensure that you give them time to redistribute
3.recapture as many individuals as possible
4.record the number of marked and unmarked
5.calculate the population size using a formula
46
what's the formula for the capture-recapture method?
*see paper flashcard*
47
describe the important of measuring abiotic factors
-abiotic factors have a direct effect on the living organisms of an area
-to enable scientists to draw conclusions about the organisms present in an area, it is important to measure the abiotic conditions at every sample point
48
what sensor is used to measure wind speed and what is it measured in?
anemometer, m s⁻¹
49
what sensor is used to measure light intensity and what is it measured in?
light meter, lux
50
what sensor is used to measure relative humidity and what is it measured in?
humidity sensor, mg dm⁻³
51
what sensor is used to measure pH and what is it measured in?
pH probe, pH
52
what sensor is used to measure temperature and what is it measured in?
temperature probe, °C
53
what sensor is used to oxygen content in water and what is it measured in?
dissolved oxygen probe, mg dm⁻³
54
how can you measure the biodiversity of an area?
one measure of the biodiversity of an area is species diversity
55
what does it mean the greater the species diversity?
the greater the stability of the community
56
what communities have large numbers of evenly distributed species in large populations?
the most stable communities
57
what does the Simpsons Index of Diversity take into account?
-species richness
-species evenness
58
what is species richness?
the number of different species living in a particular area
59
what is species evenness?
a comparison of the numbers of individuals of each species living in a community
60
in the Simpsons Index of Diversity equation, what does N stand for?
total number of organisms of all species
61
in the Simpsons Index of Diversity equation, what does n stand for?
total numbers of organisms of a particular species
62
describe the results of the Simpsons Index of Diversity
Simpsons Index of Diversity always results in a value between 0 and 1, where 0 represents no diversity and 1 represents infinite diversity. The higher the value of D, the more diverse the habitat.
63
what is genetic biodiversity caused by?
the presence of alleles
64
what are alleles?
different variations of the same gene
65
why is it beneficial for species to be as genetically diverse as possible?
they are more likely to be able to adapt to changes in the environment and therefore, less susceptible to extinction
66
what are the factors that increase genetic biodiversity?
1. mutation
2. interbreeding between populations
67
how does mutation increase genetic biodiversity?
can give rise to new alleles
68
how does interbreeding between populations increase genetic biodiversity?
when an individual migrates from one population and breeds with a member of another population, alleles are transferred between the two populations (gene flow)
69
what factors decrease genetic biodiversity?
-selective breeding
-captive breeding
-rare breeds
-artificial cloning
-natural selection
-genetic bottlenecks
-founder effect
-genetic drift
70
how does selective breeding decrease genetic biodiversity?
individuals are selected based on desirable characteristics and bred this reduces the amount of alleles present
71
how does captive breeding decrease genetic biodiversity?
it is important in maintaining species that are at risk of extinction but it means that captive populations often show little variation
72
how does rare breeds decrease genetic biodiversity?
when only a small number of individuals of a breed remain they have a small gene pool
73
how does artificial cloning decrease genetic biodiversity?
asexual reproduction produces clones and they have the same genetic material as the parent organism
74
how does natural selection decrease genetic biodiversity?
species evolve to contain primarily advantageous allele but this means alleles coding for less advantageous characteristics will be lost
75
how does genetic bottlenecks decrease genetic biodiversity?
this is when few individuals in a population survive an event e.g. disease, thus reducing the gene pool
76
how does founder effect decrease genetic biodiversity?
where a small number of individuals create a new colony, geographically isolated from the original- this new population has a small gene pool
77
how does genetic drift decrease genetic biodiversity?
random nature of alleles being passed on means the existence of the allele can disappear from a population
78
how do you measure genetic biodiversity?
-quantified by measuring polymorphism
-the greater the proportion of polymorphic gene loci, the greater the genetic biodiversity of the population
79
what is a polymorphic gene?
they have more than one allele
80
how do you find polymorphic genes?
through gel electrophoresis
81
how does gel electrophoresis work?
-DNA is fragmented with restriction enzymes
-it is run through a gel
-smaller segments move faster and further than larger segments
-data is then collected from the gel electrophoresis
-for each gene locus it can show if there is more than one allele or if there is just one allele for the gene
-this can be compared for many individuals
82
how do you calculate genetic biodiversity?
proportion of polymorphic gene loci (%) = number of polymorphic gene loci / total number of loci x 100
83
what is a keystone species?
a species which is essential for maintaining biodiversity- they have a disproportionally large effect on their environment relative to their abundance
84
what are the human influences on biodiversity?
-deforestation
-agriculture
-climate change
85
how does deforestation influence biodiversity?
-leads to reduction in number of trees in an area and can be direct or indirect (e.g. acid rain)
-reduces species diversity of plants
-destroys habitats and size of animal populations
-animals may migrate
86
how does agriculture influence biodiversity?
-agricultural land requires deforestation of habitats
-removal of hedgerows destroys habitats and reduces species diversity
-use of herbicides further reduces-biodiversity
-creates a monoculture
87
how does climate change influence biodiversity?
-melting ice caps has led to mass habitat reduction for many species
-rising sea levels has led to flooding and an increase in salinity of rivers, reducing the frequency of freshwater habitats
-high temperatures and less rainfall
-changes insect life cycles
88
what are the economic reasons for maintain biodiversity?
-desertification means less crops
-loss of raw materials is unsustainable
-large scale habitat loss means species that could be used for medicines could be extinct before they are discovered
89
what are the aesthetic reasons for maintaining biodiversity?
-presence of different plants and animals enriches our lives
-natural world provides inspiration for people such as musicians
-patients recover more rapidly from stress when they are supported by plants
90
what has biodiversity provided for us?
-fed us
-clothed us
-sheltered us
-enriched soil
-medicine
-forests filter our water
91
why is our knowledge of biodiversity limited?
most species are undiscovered/unnamed
92
what is the decode on biodiversity for?
represents an effort to prevent species loss and habitat loss
93
how many countries met to discuss the treaty on the access and benefit sharing genetic resources and to agree to a global strategic plan with concrete biodiversity objectives?
193
94
how many targets are there for the world to achieve by 2020?
20
95
how many times faster are species disappearing at the moment compared to the natural rate?
1000 times faster
96
what percentage of amphibians are declining?
42%
97
what percentage of birds are declining?
40%
98
what are the factors that are causing a reduction in biodiversity?
-overfishing
-deforestation
-climate change
-pollution
-over exploitation
-habitat loss
-invasive species
-overconsumption
99
what ecosystem services are provided by biodiversity?
-insects and birds provide pollination services for agriculture
-wetlands and forests prevent erosion and are used for carbon sequestration
100
what are the ecological reasons for maintaining biodiversity?
-all organisms are interdependent on each other for survival so the removal of one species may have a significant effect on others
-some species play a key role in maintaining the structure of an ecological community
101
define conservation
the preservation and careful management of the environment and its natural resources
102
what are the different types of conservation?
-in situ
-ex situ
103
what is in-situ conservation?
conserving a species in its natural environment, which may involve protecting the environment from people
104
what is ex- situ conservation?
conserving a species by taking i out of its natural environment
105
describe the benefits of in-situ conservation
-ideal scenario as species are in their natural habitat
-maintains evolutionary adaptations the species gain from living in its natural habitat
-preserves interdependence
-cheaper
-protects other species in same habitat
106
what are the different types of in situ-conservation?
-marine conservation zones
-legislation
-wildlife reserves
-conservation parks
-active management
-considering local people
107
what are the different forms of active management?
-controlled grazing
-halting succession
-restricting human access
-controlling poaching
-supplementary feeding
-culling invasive species e.g. grey squirrel
-reintroduction of species
108
describe marine conservation zones
-marine protected area that has legal protection against fishing or development
-large area is often required
109
describe legislation
-countries can pass laws against harmful activities such as hunting
-some countries may not want to so it can be difficult enforcing laws
110
describe wildlife reserves
-area of land that is protected and managed in order to preserve a particular type of habitat
-nature reserves, national parks and conservation areas are all types of wildlife reserves
111
describe conservation parks
-sites that are chosen carefully to conserve plant and animal species in natural environments conserving biodiversity and ecosystems
-these are actively managed
112
describe the form of active management- controlled grazing
maintains certain habitats by preventing growth of certain flora
113
why do conservation agreements exist?
-to protect endangered species and their habitats
-to ensure ecosystems function properly and provide essential services like clean air
-to reserve forests, oceans
-to preserve genetic diversity
114
what is the environmental stewardship scheme?
the responsible use and protection of the natural environment through active participation in conservation efforts and sustainable practices
115
what are the aims of the environmental stewardship scheme?
-sustaining the beauty and diversity of the landscape
-improving, extending and creating wildlife habitats
-restoring neglected land and conserving archaeological and historic features
-improving opportunities for countryside employment
116
what does the IUCN stand for?
International Union for the Conservation of Nature
117
what does the IUCN do?
-its main goal is to advance sustainable development and support conservation of species
-input projects on local, national and international levels to tackle issues such as habitat loss
118
what are some examples of the IUCN?
the Malaysian giant turtle is critically endangered on the red list- to combat this there are areas of protection in place in many of their common habitats
119
what does CITES stand for?
Convention on International Trade in Endangered Species
120
what does CITES do?
It regulates the international trade of wild plant and animal specimens and their products
Today, more than 35 000 species of animals and plants are protected by this treaty
121
what are the problems with CITES?
-it can be hard to categorise animals into one appendix causing confusion
-hard to enforce as some countries have cultural ties to goods
122
when did the Rio Convention first happen?
in 1992
123
how many nations were at the Rio Convention?
172
124
what are the 3 key agreements that emerged from the Rio Convention?
-Convention on Biological Diversity
-United Nations Framework Convention on Climate Change
-United Nations Convention to Combat Desertification
125
what does the Convention on Biological Diversity require countries to do?
develop national strategies for sustainable development which ensures the maintenance of biodiversity
126
what is the United Nations Framework Convention on Climate Change?
an agreement between nations to take steps to combat climate change by reducing greenhouse gas emissions and stabilising global climate
127
what does the United Nations Convention to Combat Desertification aim to?
aims to prevent fertile land from transforming to desert and reduce the effects of drought by promoting practices that avoid, reduce and reverse land degradation
128
describe considering local people
-in situ conservation should meet the needs of indigenous people
-the relationship has to be managed so that they can maintain their way of life and help to maintain the conservation otherwise can conflicts arise.
-such conflicts arise from predation of livestock and illegal poaching.
129
when is ex situ often used?
in conjunction with in situ conservation
130
what are the types of ex situ conservation?
-botanical gardens
-seed banks
-zoos
-captive breeding
-gene banks
-artificial insemination
-in vitro fertilisation
-reproductive physiology
131
describe botanical gardens
-these are places of conservation with endangered species of plants
-they contain seeds collected from the wild and germinated and then can be replanted in the wild
-may not represent full genetic diversity especially with asexual reproduction
132
describe seed banks
-store a representative seed sample from every known plant species
-seeds stored until they are needed
-stored in conditions so they will last decades, maybe even centuries
133
describe zoos
-in the past, zoos were primarily for entertainment but now they have an important role in conservation.
-can maintain populations of animals that would be unlikely to survive in the wild
134
describe the issues with captive breeding in zoos
-expensive
-failure to successfully pair / breed animals
-limited space.
-low genetic biodiversity
-species is less able to adapt to changing conditions
-animals unlikely to survive in the wild
135
define habitat
the part of an ecosystem where a particular organism lives
