Populations and sustainability

Question 1

Points for competition between species

Answer 1

-Identify what type of competition it is inter/intra
-Out compete for resources - most adapted will survive
-Competitive exclusion principle
-Limiting factors

Question 2

Analysis of a graph - competition between two different species

Answer 2

-Changes could be explainable by chance
-Correlation does not mean cause

Question 3

Limiting factors

Answer 3

-New disease
-New predator
-Temperature
-Loss of a food source

Question 4

Improvements to help the conservation of peat bogs

Answer 4

Less plating as trees remove water from the bog; no ditch as ditch drains water ;

No controlled grazing - grazing disrupts the food chain

No less burning - death of an organism

Question 5

What is the preservation and why would a peat bog need to be conserved

Answer 5

Preservation: leaves ecosystems untouched/ without human interference
Most peat bogs have been damaged already and require management and restoration

Question 6

How do you know if a habitat has been conserved

Answer 6

The habitat has been changed - not the original habitat

Question 7

How to produce timber sustainably

Answer 7

Replanting / minimum distance/ space between trees/ limit soil erosion after felling

Question 8

What is coppicing

Answer 8

Coppicing is cutting the tree at an angle near the base so that new shoots can grow. Many thin shoots will then grow from this base.

Question 9

Advantages of coppicing

Answer 9

-Promotes different light levels in the habitat
-Prevents succession
-Reduces competition for light
-Process can be repeated indefinetly
-New stems grow more rapidly then saplings
-Lifespan of the tree extended
-soil erosion prevented

Question 10

Measures for sustainable fishing

Answer 10

1) fishing quotas
2) mesh size
3) species restriction
4) trawler size / days at sea
5) penalties / sanctions
6) monitoring / surveillance
7) publicity / public education

Question 11

Difficulties for sustainable fishing

Answer 11

area too large
expense of monitoring
monitoring hampered by, weather
/ seasons
false reporting of, catches / trawler
size / mesh size / days
death of fish caught but not kept
(because of restrictions)

Question 12

keystone species

Answer 12

Have a significant impact on the ecosystem
Many other species rely on the activity of the organism