B6.1

Question 1

What is sampling?

Answer 1

Taking observations or measurements from a small area, which is representative of a larger area
You then scale up the sample to make estimates about the larger area

Question 2

What are the different apparatus/techniques for animal sampling?

Answer 2

• Pooter - suck on the mouthpiece to draw insects into the holding chamber, a filter stops the organisms entering the mouth
• Sweep nets - sweep a large net through the air to catch any flying insects or those in long grass
• Kick sampling - ‘kick’ a river bank of bed to disturb mud and vegetation. Hold a net downstream to capture any organisms released into the flowing water
• Tree beating - stretch a large white cloth under a tree, then shake or beat the tree to dislodge any invertebrates which will fall into the cloth
• Pitfall traps - dig a hole into the ground, which crawling invertebrates can fall into. Cover a hole with a roof so the trap downt fill with rain water

Question 3

What are the two identification keys?

Answer 3

Branched key - by answering yes or no for each question youmvan identify the organisms identity
Numbered key (dichotomous key) - correct answer to a question tells you which question you need to answer next. After a series of questions you’ll know the specis

Question 4

What is the capture-reccapture method and what is it used for?

Answer 4

1) capture organisms from a sample area
2) mark individual organism, then release back into the community
3) at a later date, recapture the organsims in the original sample area
4) record the number of marked and unmarked individuals
5) estimate the population size

Question 5

How do you estimate the population size?

Answer 5

Estimated population size = first sample size x second sample size / number of recaptured marked individuals

Question 6

How can you sample plants?

Answer 6

1) place a quadrat (square frame divided into a grid) on the ground
2) take a sample and record the type and number of each organism in each section
3) take a number of samples and calculate a mean
4) to work out the whole population multiply the mean population per m^2 by the total area
Before recording your findings, decide if you would count a flower half inside the quadrat counts as 1

Question 7

What is random sampling?

Answer 7

Using a random generator and determine coordinates to place the quadrant
Prevents bias

Question 8

What is non random sampling?

Answer 8

Samples can be taken along a long line, called a transect

Question 9

Why is biodiversity important?

Answer 9

Essential for maintaining a balanced ecosystem

Question 10

How is biodiversity lost by deforestation?

Answer 10

Permanent removal of large areas of forest
- for wood for building and fuel, also creates space for roads and buildings and agriculture.
BUT
Reduces both number of trees and number of supported animal species, their food source or habitat has been lost

Question 11

How is biodiversity lost by agriculture?

Answer 11

Many intensive farming techniques are used for the growing population
- removing hedgerows to use large machines and free up extra land for crops. Number of plants and habitats decrease
- use of pesticides to kill pests, removes a food source for many animals. Pesticides can also accumulate across the food chain and reach other animals
- use of herbicides to kill unwanted plants, reduces plant species and habitats

Question 12

How is biodiversity lost by hunting & fishing?

Answer 12

• overfishing has led to some fish population decreasing or even being lost
• hunting decreases the target species population which removes food for other species which then outcompetes other plants

Question 13

How is biodiversity lost by pollution?

Answer 13

When pollutants enter the environment they have an impact on the number and types of organisms
More polluted areas have fewer numbers of species

Question 14

What is eutrophication.

Answer 14

When fertilisers run into lakes they cause algal bloom which prevents light from reaching the bottom of the water causing the plants below to die
As microorganisms decompose the dead plants and algae the oxygen decreases and the fish die

Question 15

What are the ways to prevent loss of biodiversity?

Answer 15

Conservation
Selective breeding
Seed banks

Question 16

What is conservation?

Answer 16

Means protecting a natural environment to ensure habitats are not lost
If an organisms habitat is protected it increases their chance of survival and allows them to reproduce

Question 17

How are nature reserves managed?

Answer 17

Controlled grazing - only allowing animals to graze land for a certain period of time, giving plant species time to recover
Restricting human access - providing paths so plants aren’t trampled on
Feeding animals - ensure more organisms survive to a reproductive age
Reintroduction of species - adding new species to an area where numbers have decreased significantly

Question 18

What is captive breeding?

Answer 18

Breeding animals in a human controlled environment (zoos, aquariums)
Animals are given shelter, plenty of foods and vetinsry trament and also a predator free environment
Suitable breeding partners can be found

Question 19

What to captive breeders aim to do?

Answer 19

• create a stable, healthy population of a species
• gradually reintroduce the species back into its natural habitat

Question 20

What is the problem with captive breeding?

Answer 20

• maintaining genetic diversity as there are few breeding partners available
• organisms born into captivity aren’t suitable to release into the wild

Question 21

How can we prevent extinction?

Answer 21

Seed banks
Seeds are carefully stored to be grown in the future

Question 22

What is a seed bank?

Answer 22

Way of conserving plants
Example of a gene bank - a store of genetic material

Question 23

What are conservation agreements?

Answer 23

To conserve biodiversity, local and international cooperation is required to preserve habitats and individual species
Also many animals move between countries

Question 24

What are some international agreements?

Answer 24

IUCN - has a ‘red list’ which details the current conservation status of threatened animals and countries can work together to conserve these species
CITES - a treaty that regulates the international trade of wild plants and animals to prevent over exploitation. Protects over 35,000 species
Rio convention - require countries to develop strategies for sustainable development, reduce green emissions and combat desertification. All to maintain biodiversity

Question 25

What is ecotourism?

Answer 25

Ecotourism aims to ensure tourism doesn’t have a negative impact on the natural environment of local communities
TIB large numbers of tourists can lead to loss of habitats but tourism also brings money to support natural wildlife

Question 26

How is pollution monitored?

Answer 26

Samples of plants and animals are often taken from the environment
Indicator species are organisms that are used to measure environment quality

Question 27

How are organisms used to monitor air pollution?

Answer 27

A common form of air pollution is sulfur dioxide form combustion of some fossil fuels which produces acid rain
Lichen are indicator species that don’t have roots so obtain their minerals from the rain so if they die then it is indication of acid rain
Lack of lichen is an indication of high pollution

Question 28

How are organisms used to monitor water pollution?

Answer 28

Caused by the discharge of harmful substances into rivers, lakes and seas
Higher level of pollution means lower level of dissolved oxygen
Oxygen content can be estimated by identifying indicator species found living in it as some require higher oxygen content

Question 29

What are the indicator species with different levels of water pollution?

Answer 29

Unpolluted - mayfly larva
Low pollution - freshwater shrimp
High pollution - water louse
Very high pollution - sludgeworm