Option G: Ecology and Conservation

1. Option G: Ecology and Conservation

2. Outline the factors that affect the distribution of plant species: • Temperature • Water • Light • soil pH • salinity • mineral nutrients (NPK etc.) Prefers acidic soil Salt tolerant

3. Explain the factors that affect the distribution of animal species: • Temperature • water • breeding sites • food supply • territory

4. Describe one method of random sampling, based on quadrat methods, that is used to compare population size of two plant or two animal species. • 1.Mark out gridlines along 2 edges of the area to be sampled. • 2. Generate two random numbers and place the corner of the quadrat at the coordinates • 3. Count the individuals of interest in the quadrat • 4. Repeat steps 2 and 3 as much as possible. • 5. Measure the total size of the area occupied by the population in square meters • 6. Calculate the estimated population size for the area: • Pop. Size = mean number per quadrat x total area area of each quadrat • Compare your count to a count from another area of interest.

5. Outline the use of a transect to correlate the distribution of plant or animal species with an abiotic variable. • Transect = more systematic • Done along a line (not random) • How would this be done?

6. A trapped weasel • Describe one technique used to estimate the population size of an animal species based on a capture-mark–release–recapture method. • Knowledge of the Lincoln index (which involves one • mark–release–recapture cycle) is required, as follows. • Population size= (n1 x n2) /n3 • where n1 = number of individuals initially caught,marked and released, • n2 = total number of individuals caught in the second sample, and • n3 =number of marked individuals in the second sample.

7. The Niche • Ecological niche~ all the characteristics, biotic and abiotic, specific to a species. It includes: • spatial habitat • feeding activities • Interactions with other organisms. Distinguish Fundamental vs. realized niches • fundamental/theoretical~ the niche a population is theoretically capable of occupying under ideal conditions • realized~ the niche population actually occupies Ex: Barnacle sp. on the coast of Scotland

8. The Competitive Exclusion Principle • 2 species with similar needs for the same limiting resources cannot coexist in the same place • Thus, 2 species cannot coexist in a community if their niches are identical • Why? • example experiment

9. Interactions/Symbiosis Definition: Symbiosis is a close ecological relationship between the individuals of two (or more) different species.   Sometimes a symbiotic relationship benefits both species, sometimes one species benefits at the other's expense, and in other cases neither species benefits.

10. Types of Symbiosis Ecologists use a different term for each type of symbiotic relationship: Mutualism   --   both species benefit Commensalism   --   one species benefits, the other is unaffected Parasitism   --   one species benefits, the other is harmed Competition   --   neither species benefits Neutralism   --   both species are unaffected

11. Interactions

12. Biomass • Biomass: the dry weight of organic matter in organisms of an ecosystem. • Describe one method for the measurement of biomass of different trophic levels in an ecosystem. • Get dry weight of organism • Estimation necessary sometimes • Can be destructive (ethical issues?) Felling a 30-year old agroforestry black walnut to measure its biomass and allometrics.

13. Matter and Energy Flow, I • Primary production (amount of light energy converted to chemical energy by autotrophs) • Gross production(GP): the total amount of organic material produced by producers in an ecosystem • Net production (NP): gross production minus the material expended by producers in respiration. (stored energy available to consumers) • R: respiration • NP = GP - R

14. Energy Flow, II • Ecological efficiency: % of E transferred from one trophic level to the next (5-20%) (average =10%) • Pyramid of productivity: shows multiplicative loss of energy in trophic levels • Biomass pyramid: trophic representation of biomass in ecosystems • Pyramid of numbers: trophic representation of the number of organisms in an ecosystem

15. Check yourself #1 • Discuss the difficulties of classifying organisms into trophic levels. • Explain the small biomass and low numbers of organisms in higher trophic levels. • Construct a pyramid of energy given appropriate information. • Describe an example for each of the symbiotic relationships described.

16. Succession • Ecological succession~ transition in species composition over time • Primary ~ begun in lifeless area; no soil, (perhaps volcanic activity or retreating glacier) Lichens= pioneer species • Secondary~ an existing community has been cleared by some disturbance that leaves the soil intact • Climax community

17. Check yourself • Distinguish between primary and secondary succession, using an example of each. • Outline the changes in species diversity and production during primary succession. • Explain the effects of living organisms on the abiotic environment, with reference to the changes occurring during primary succession.

18. Biomes • I. Biome= a large group of ecosystems that share the same type of climax community • Type of biome determined largely by: • Precipitation • temperature

19. 2. Major terrestrial biomes a. tundra—treeless (or very small trees may be present), permafrost, low nutrient soil, low precipitation. slow decay. Around poles. b. taiga—northern coniferous forest—acidic/nutrient poor topsoil, long harsh winters, short summers. Cold but no permafrost. c. desert—low precipitation, warm to very hot days and cold nights, very few plants (some store water, some grow quickly with rain.) d. Grassland—few trees, low rainfall, warm to hot summers, cold winters. Dominated by grasses and plants tolerant of grazing. experience a dry season, unpredictable precipitation, fertile soil. e. temperate deciduous forest—trees lose leaves, warm summers, cool winters. Moderate rainfall. f. tropical rain forest— hot in all seasons,soil is nutrient poor. Rains frequently/ high precipitation. Highest biodiversity of terrestrial biomes. Canopy prevents understory plant growth.

20. Check Yourself #2 Explain how rainfall and temperature affect the distribution of biomes. Outline the characteristics of six major biomes include in your description the major flora and fauna or provide a picture.

21. Simpson’s Diversity Index Simpson's Diversity Index is a measure of diversity. In ecology, it is often used to quantify the biodiversity of a habitat. It takes into account the number of species present, as well as the abundance of each species.

22. Calculate the Simpson diversity index for two local communities. • Analyse the biodiversity of the two local communities using the Simpson index. • The Simpson diversity index is a measure of species diversity • D is the diversity index, • N is the total number of organisms of all species found • n is the number of individuals of a particular species. • A high value of D suggests a stable and ancient ecosystem and a low D value could suggest pollution, recent succession or agricultural management. • The index is determined by counting organisms on randomly chosen parts of an area. Monitoring over time shows changes in an ecosystem.

23. Example: N = 42 Get n for each species and plug in. D= ___42 (42-1)______ 8 (8-1) + 5 (5-1) + 4 (4-1) etc… D = ___42 (42-1)______ 140

24. Practice problem: Calculate the Simpson diversity index for the following community:

25. Check Yourself #3 • Discuss reasons for the conservation of biodiversity using rainforests as an example.

26. Rainforest Example • Economic reasons • Ecotourism • New products/drugs • Ecological reasons • Ecological relationships/symbiosis • Erosion • Carbon and oxygen cycles • Climate effects • Ethical reasons • Intrinsic value of living things • Cultural importance of native species • Effects on future generations • Medicines (potentially) • Aesthetic reasons

27. II. Importance of Biodiversity A. Beauty B. ecological relationships between organisms C. Importance to people—medicines (Taxol-Pacific Yew), mold- penicillin, rosy periwinkle—drugs for Hodgkin’s disease (lymphatic cancer) and leukemia, Willow bark—aspirin, cinchona tree bark—quinine) Other uses?

28. List three examples of the introduction of alien species that have had significant impacts on ecosystems.Discuss the impacts of alien species on ecosystems. • 3 examples of alien species • Brown tree snake in Guam (see biological invaders http://www.pbs.org/cgi-registry/2wgbh/evolution/library/search.cgi • Cane toad in Australia (originally introduced to control sugar cane pests) http://video.nationalgeographic.com/video/player/animals/amphibians-animals/frogs-and-toads/toad_cane.html • Fennel and European grasses in CA (more info on fennel:http://www.cal-ipc.org/ip/management/ipcw/pages/detailreport.cfm@usernumber=51&surveynumber=182.php)

29. Some California Native Plants • Island Buckwheat, Channel Islands, California • Dudleya, Channel Islands, California Indian Paintbrush • Lemonade Berry, Channel Islands, California

30. Fennel: the alien • Removing invasive fennel

31. Outline one example of biological control of invasive species. • http://www.sciencedaily.com/releases/2008/05/080508131953.htm

32. Check Yourself #4 Find one invasive plant species and one invasive animal species in Oregon. What are the consequences of this invasion?

33. Define biomagnification. • Biomagnification: process by which chemical substances become more concentrated at each higher trophic level. • Explain the cause and consequences of biomagnification, using a named example. • Cause: • Consequences: • Named examples: Mercury in fish, DDT and pelicans, eagles, Island foxes.

34. Outline the effect of chlorofluorocarbons (CFC’s) on the ozone layer. • ozone in the stratosphere absorbs UV radiation. • Chlorine breaks away from CFC molecules (caused by UV light) • Chlorine (highly reactive) reacts with ozone (breaks it down to make oxygen) • One chlorine can break down hundreds of thousands of ozone molecules. • Animation http://www.bom.gov.au/lam/Students_Teachers/ozanim/ozoanim.shtml

35. Outline the effects of UV radiation on living tissues and biological productivity. • a) Increases the mutation rates in DNA. • b) Causes severe sunburns and damage to eyes (cataracts). • c) Increases incidence of cancers (melanoma). • d) Reduces rate of photosynthesis in plants (lowers energy output of producers!).

36. Explain the use of biotic indices and indicator species in monitoring environmental change. • Indicator species— • highly sensitive to environmental changes • their populations increase or decrease significantly depending on changes in the environment. • Ex. Frogs and pollution http://environment.newscientist.com/article/dn12687-frog-deformities-linked-to-farm-pollution.html • Ex. sludge worms-- indicate low oxygen concentration in water. • Biotic index: Scale for showing the quality of an environment by indicating the types of organisms present in it (e.g. how clean a river is). (Source: PHC) Ex.http://www.pisces-aqua.co.uk/aquatext/tables/bioticind.htm

37. Check yourself #5 • Explain the use of biotic indices and indicator species in monitoring environmental change.

38. Outline the biogeographical features of nature reserves that promote the conservation of diversity. • Large size (why?) • Avoid habitat fragmentation and edge effect (ex. Cowbirds parasitize nests on forest edges) • Habitat corridors to connect fragmented habitats. • Inclusion of a variety of abiotic factors also promotes diversity. (Why? Discuss)

39. Discuss the role of active management techniques in conservation. • If human disturbance has degraded a habitat, active management may be necessary. (It won’t always return to its natural state on its own) • Example: removing goats, pigs, golden eagles, and invasive plants on the Channel Islands

40. Discuss the advantages of in situ conservation of endangered species(terrestrial and aquatic nature reserves). • In situ = Nature reserves • Advantages: • Species are adapted to habitat • Genetic diversity • Natural behavior patterns • Interaction of species in ecosystem Wolong Nature Reserve (China) Jaguar Preserve (Belize)

41. Outline the use of ex situ conservation measures, including captive breeding of animals, botanic gardens and seed banks. • Captive breeding • Botanic gardens • Seed banks (most seeds kept cold -10-20 C can last over 100 years)

42. Check Yourself #6 Outline the factors that contributed to the extinction of one named animal species. • Pick a species that you will remember! • Outline the factors that contributed to it’s extinction in your notes. • Include a picture of your animal species if possible!

43. Reproductive patterns r strategists--rapid life histories, rapid reproduction of many small offspring in unpredictable unstable environments k strategists—large, reproduce and mature slowly, long-lived, often care for young In stable environments

44. Check Yourself #7 • Distinguish between r-strategies and K-strategies. • Discuss the environmental conditions that favour either r-strategies or K-strategies.

45. Describe the methods used to estimate the size of commercial fish stocks. • Use fish catch data to get a count and age distribution. Use this to estimate in conjunction with spawning rates and survivorship curves • Capture-mark-release-recapture • Works in lakes, but not in oceans • Echo sounders in conjunction with trawling to determine which species have been echolocated. • None of these methods estimate with much certainty leading to disagreements.

46. Outline the concept of maximum sustainable yield in the conservation of fish stocks. • Maximum sustainable yield = Largest amount of fish that can be harvested without a decline in fish stocks.

47. Discuss international measures that would promote the conservation of fish. • Monitoring stocks and repro rates • Quotas for species with low stocks • Closed seasons (esp. breeding season) • Exclusion zones with no fishing allowed • Moratoria on catching endangered species • Minimum net sizes (so baby fish aren’t caught) • Banning of drift nets “A lone bat ray is  tangled in the mesh of a drift net. Not considered for human consumption, this ray will likely be thrown overboard once the net is hauled in.” (Ocean.com)

48. Check Yourself #8 Which of these measures do you think would be most effective? Why?