Biodiversity and Sampling Methods
This section delves into the concept of biodiversity and various sampling techniques used in ecological studies.
Definition: Biodiversity is the variety of living organisms within an ecosystem or on Earth as a whole.
The document outlines several methods to measure biodiversity, including species richness, species evenness, genetic diversity, and the index of diversity. It then explores different sampling methods used in A Level Biology studies:
- Systematic Sampling: Follows a specific pattern, such as sampling every 5 meters.
- Opportunistic Sampling: Data is collected when a particular organism is encountered.
- Random Sampling: Provides a representative sample of the area under investigation.
- Stratified Sampling: Populations are divided into smaller groups strata based on common characteristics.
Example: A transect line with quadrats placed at regular intervals is an example of systematic sampling in OCR A Level Biology PAG 3.1.
The importance of biodiversity is emphasized for ecological, economic, and aesthetic reasons.
Highlight: Maintaining biodiversity is crucial for ecological balance, economic benefits like ecotourism, and preserving natural landscapes.
The document then discusses conservation methods, including in situ and ex situ approaches. In situ methods involve protecting wildlife in their natural habitats, while ex situ methods include zoos, seed banks, and botanical gardens.
Vocabulary: In situ conservation refers to protecting species in their natural habitats, while ex situ conservation involves preserving species outside their native environments.
Zoos play a significant role in conservation through scientific research, captive breeding programs, reintroduction efforts, and education initiatives. Seed banks are highlighted as an efficient method for conserving plant genetic diversity.
Example: The Millennium Seed Bank Project is a prime example of ex situ conservation in A level Biology, storing seeds from a vast array of plant species to safeguard against extinction.
