1. Option G: Ecology and Conservation Chpt. 18: pages 552 - 600

2. Biodiversity  The variability of organisms from all sources.  Includes variability within species, between species, and of ecosystems.  Biodiversity includes genetic variation within species, the variety of species in an area, and the variety of habitat types within a landscape.

3. Community Ecology G.1  Plants and animals are affected by different factors that determine their distribution  Populations can be sampled to determine diversity and distribution of organisms

4. G.1.1 Factors affecting plant distribution  Temperature  Light  Soil pH  Salinity  Nutrient content of soil

5. G.1.2 Factors affecting animal distribution  Temperature  Water  Breeding sites  Food supply  Territory

6. Random Sampling  Samples must come from all parts of the habitat  Each organism must have an equal chance of being selected.

7. Quadrat Method  A quadrat is a square of a particular size. Size depends on the type of area being surveyed and type of organism being studied

8. Steps of quadrat method  Map area of interest  Determine size of quadrats  Place a grid with numbers over map  Use a random numbers table to choose squares for sampling  Count organism of interest in selected squares  Average the number of the organisms in your selected squares

9.  Multiply the average number of the selected organism times the number of quadrats on the map

10. The transect technique  Used for studying how the distribution of plants in an ecosystem is affected by abiotic factors

11. Steps to perform a transect on a beach  Run a tape from the tide line to the dunes at right angle to the water  Every 10-20 meters along tape mark a quadrat (each being the same size)  Identify and count plant species of interest in each quadrat  Measure abiotic features (T, light, soil pH, moisture, mineral content) in each quadrat  Examine pattern of distribution

12. Niche – an organisms role in the ecosystem  Includes Where the organism lives What and how the organism eats How the organism interacts with other species

13.  Spatial habitat-the specific area an organism inhabits  Feeding activities – affect the ecosystem by keeping other populations in check  Interactions Competition Predator/prey Parasitism Mutualism

14. Parasitoid wasp larva and corpse of caterpillar (skin and hair)! Unsuspecting caterpillar!

15.  Read pages 558-559 for examples of interactions between species. Homework!  Research these interactions and find 3 MORE examples of each!

16. Competitive Exclusion  No two species in a community can occupy the same niche  Demonstrated by Gause in 1934 using two species of Paramecium grown in separate cultures thrived  When grown together one species died and the other survived. One out competed the other for resources

17.  Gausian hypothesis of competitive exclusion – when 2 species have a similar need for the same resources, one will be excluded

18. If animals have the same niche one of two things will happen:  Competitive Exclusion – one species will be driven to local extinction  Resource Partitioning – one species may evolve to use a different set of resources

19. Fundamental vs. Realized Niche  Fundamental niche – the potential mode of existence, given adaptations of the species  Realized niche – the actual mode of existence, results from adaptations of the organism and competition

20. Biomass  The total mass of organic matter (carbohydrates, lipids, proteins)  Water is inorganic so all material must be dried to measure biomass  Measured as dry mass in g/m 2 /y or gm -2 y -1

21. Measuring biomass  Must collect animals and determine their biomass using a table (based on size and weight)  Plants can be collected, dried and weighed

22. Measuring biomass of a terrestrial ecosystem  Measure total area of ecosystem and divide into plots  Select a plot to sample  Measure size of each plant species (trees, low growing vegetation). Cut all vegetation on the plot  Dry all plant samples  Use a mathematical model to show relationship between weight and height of each plant and its biomass

23.  Sample other plots by measuring size and height of plants. Use mathematical model to find biomass  Collect animals by trapping. Weigh and measure. Use table to determine biomass  Average data for all species per plot  Multiply average times number of plots to find biomass of entire ecosystem  Repeat seasonally or yearly to study changes