QUESTIONS: 1. Name three ways human directly alter ecosystems. 2. Why is the impact of human greater today than at any time in the past? 3. Describe three factors that influence the genetic diversity of a population. 4. Describe three major cause of the loss of biodiversity. 5. What are the major causes of biodiversity loss in marine ecosystems? 6. List three problems associated with forest exploitation. 7. What is desertification? What causes it? 8. List three key components of the convention on Biological Diversity (biodiverty treaty). 9. List six techniques untilized by wildlife managers. 10. What is extintion, and why does it occur? 11. List three examples of ecosystem services provided by biological resources. 12. List three actions that can be taken to prevent extinctions.

1. Group 12:
1. PHAI MINEA [Leader: 0966153104] (ID: 2119055)
2. LAO SOKKEANG [0966973633] (ID: 2119639)
3. OL KIMMEY [098661176] (ID: 2120522)
4. RITH CHHAINGIM [0969071860] (ID: 2121245)

2. REVIEW QEUSTIONS
QUESTIONS:
1. Name three ways human directly alter ecosystems.
2. Why is the impact of human greater today than at any time in the past?
3. Describe three factors that influence the genetic diversity of a population.
4. Describe three major cause of the loss of biodiversity.
5. What are the major causes of biodiversity loss in marine ecosystems?
6. List three problems associated with forest exploitation.
7. What is desertification? What causes it?
8. List three key components of the convention on Biological Diversity (biodiverty treaty).
9. List six techniques untilized by wildlife managers.
10. What is extintion, and why does it occur?
11. List three examples of ecosystem services provided by biological resources.
12. List three actions that can be taken to prevent extinctions.

3. ANSWERS
1. Name three ways human directly alter ecosystems.
Answer 1:
Name three ways humans directly alter ecosystems. We change ecosystems by
replacing them with agricultural ecosystems, we alter species by introducing plants
and animals, and we reduce populations by harvesting trees and animals for our use.
2. Why is the impact of human greater today than at any time in the past?
Answer 2:
Today the human impact on the environment is greater because the population
is greater than ever before, and technology is now more advanced and harmful
towards the environment.
3. Describe three factors that influence the genetic diversity of a population.
Answer 3:
A number of evolutionary processes such as selection, gene flow, and
historical demography affect the genetic diversity in a population (Hayes and Fox
1991; Boettcher et al. 1995; Bazin et al. 2006). The genetic diversity of individuals
within a population affects a range of ecological and evolutionary factors.
4. Describe three major cause of the loss of biodiversity.
Answer 4:
Biodiversity loss is caused by five primary drivers: habitat loss, invasive
species, overexploitation (extreme hunting and fishing pressure), pollution, climate
change associated with global warming.
5. What are the major causes of biodiversity loss in marine ecosystems?
Answer 5:
Fishing, land use change are the most significant threats to marine
biodiversity. In the ocean, fishing has had the single greatest impact on biodiversity
over the past 50 years.
6. List three problems associated with forest exploitation.
Answer 6:

4. Problems associated with forest exploitation are exposure of soil to increased
erosion, loss of animal habitat and biodiversity, stream-bank, stream siltation,
increased water temperature, and a loss of scenery.
7. What is desertification? What causes it?
Answer 7:
Desertification is the degradation process by which a fertile land changes itself
into a desert by losing its flora and fauna, this can be caused by drought,
deforestation, climate change, human activities or improper agriculture.
Desertification is a process of degradation of the land.
8. List three key components of the convention on Biological Diversity (biodiverty
treaty).
Answer 8:
The Convention has three main goals: the conservation of biological diversity
(or biodiversity); the sustainable use of its components; and the fair and equitable
sharing of benefits arising from genetic resources.
9. List six techniques untilized by wildlife managers.
Answer 9:
List six techniques utilized by wildlife managers.
• Habitat analysis.
• Population censures methods.
• Stocking areas with game species.
• Predator control.
• Establishing refuges.
• Habitat management.
•
10. What is extintion, and why does it occur?
Answer 10:
Extinction is the dying out of a species. Extinction plays an important role in
the evolution of life because it opens up opportunities for new species to emerge.
Extinction occurs when species are diminished because of environmental forces such
as habitat fragmentation, climate change, natural disaster, overexploitation by
humans, and pollution, or because of evolutionary changes in their members (genetic
inbreeding, poor reproduction, decline in population numbers).
11. List three examples of ecosystem services provided by biological resources.
Answer 11:

5. Examples of ecosystem services include products such as food and water,
regulation of floods, soil erosion and disease outbreaks, and non-material benefits
such as recreational and spiritual benefits in natural areas.
12. List three actions that can be taken to prevent extinctions
Answer 12:
• Legislations to protect species that are in danger of becoming extinct.
• The preservation of the habitat required by endangered species
• Education of the local population about the need to protect endangered
species.