TOPIC C. Species and Communities

Transcription

1 TOPIC C Species and Communities

2 C.1: THE DISTRIBUTION OF SPECIES IS AFFECTED BY LIMITING FACTORS Plant: abiotic factors Animal: abiotic + biotic How to study tolerance? Ex: use transect for plants

3 height above chart datumim] Enteromorpho sp. r Fucus spiralis Arenícolo morino Fucus serrotus Sorgossum muticum Littorino maríoe Anemonia viridis Littor no littored Chondrus crispus Potellø vulgotø S.balanoides Lominorio digitoto Gibbulo cinerorio Lourencio pinnotfida Nucello lopillus 4 shingle Þ large shallow rock pool ; a A C FO R abundance scale a - -+ shore distance L-r :5m edge of Iedge > f+ a<- <>- +

4 NICHE CONCEPT Niche Competitive exclusion resource partitioning Fundamental vs Realized niche Character displacement

5 Competitive exclusion

6 Figure 41.2 A. distichus perches on fence posts and other sunny surfaces. A. insolitus usually perches on shady branches. A. ricordii A. aliniger A. distichus A. insolitus A. christophei A. cybotes A. etheridgei 2014 Pearson Education, Inc.

7 Fundamental vs Realized Niche

8 Figure 41.4 G. fuliginosa G. fortis Character displacement Beak depth 60 Los Hermanos Percentages of individuals in each size class Daphne 2014 Pearson Education, Inc. Santa María, San Cristóbal G. fuliginosa, allopatric G. fortis, allopatric Sympatric populations Beak depth (mm)

9 C.2: CHANGES IN COMMUNITY STRUCTURE AFFECT AND ARE AFFECTED BY ORGANISMS Ecosystem analysis skills Climate graphs Pyramids of Energy Gersmehl Diagrams

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11 Gersmehl Diagrams Gersmehl diagrams describe energy flow and nutrient recycling of different biomes A common method of demonstrating the cycling of nutrients within the main stores of an ecosystem

12 Gersmehl Diagrams Arrows of varying thickness represent nutrient transfer Circles of varying sizes represent the size of the nutrient stores Included in the diagrams: Input- nitrogen, carbon, minerals Output- loses of nutrients by leaching and runoff Flows- such as leaf and needle fall from biomass to litter, and uptake of nutrients from the soil

13 Skill Construction of Gersmehl diagrams to show the inter-relationships between nutrient stores and flows between taiga, desert and tropical rainforest

14 Construct a Gersmehl Diagram: Rainforest Always read the information first! Biomass is the main store of nutrients because the tropical rainforest has tall, dense vegetation with many layers and multiple species Precipitation (P): rainfall is high all year Litter has a very small store of nutrients because of the high rate of decomposition Soil has a very small store of nutrients because of leaching and low soil fertility Weathering (W) is rapid because of high heat and humidity Leaching (Le) is high because of high rainfall (Leaching is the process of extracting minerals from a solid by dissolving them in a liquid) Runoff (R) is high due to such large amounts of rain, that the soil cannot absorb it at all

15 Construct a Gersmehl Diagram: Rainforest Biomass is the main store of nutrients because the tropical rainforest has tall, dense vegetation with many layers and multiple species Precipitation (P): rainfall is high all year Litter has a very small store of nutrients because of the high rate of decomposition Soil has a very small store of nutrients because of leaching and low soil fertility Weathering (W) is rapid because of high heat and humidity Leaching (Le) is high because of high rainfall (Leaching is the process of extracting minerals from a solid by dissolving them in a liquid) Runoff (R) is high due to such large amounts of rain, that the soil cannot absorb it at all Middle L p. 46 Use this model to help you set up your G. Diagram

16 Construct a Gersmehl Diagram: Rainforest Biomass is the main store of nutrients because the tropical rainforest has tall, dense vegetation with many layers and multiple species Precipitation (P): rainfall is high all year Litter has a very small store of nutrients because of the high rate of decomposition Soil has a very small store of nutrients because of leaching and low soil fertility Weathering (W) is rapid because of high heat and humidity Leaching (Le) is high because of high rainfall (Leaching is the process of extracting minerals from a solid by dissolving them in a liquid) Runoff (R) is high due to such large amounts of rain, that the soil cannot absorb it at all

17 Construct a Gersmehl Diagram: Taiga Litter is the largest store of Middle R p. nutrients because of the low rate of decomposition as a result of low temperatures Run-off is high. The ground is still frozen when the snow is melting Biomass is relatively low because conifers have only one layer of needles and there is no undergrowth Transfer from biomass to litter is high because of the constant supply of needles falling from coniferous trees Soil stores are very small. Poor soil is formed from glacial deposits and so there is low soil fertility Weathering of rocks is slow because of the cold Use this model to help you set up your G. Diagram 46

18 Construct a Gersmehl Diagram: Taiga Litter is the largest store of nutrients because of the low rate of decomposition as a result of low temperatures Run-off is high. The ground is still frozen when the snow is melting Biomass is relatively low because conifers have only one layer of needles and there is no undergrowth Transfer from biomass to litter is high because of the constant supply of needles falling from coniferous trees Soil stores are very small. Poor soil is formed from glacial deposits and so there is low soil fertility Weathering of rocks is slow because of the cold

19 IB BIOLOGY 2 ECOLOGY TOPIC C POPULATION ECOLOGY

20 POPULATION ECOLOGY TOPIC C

21 Population Size TOPIC C.5 POPULATION ECOLOGY = number of individuals of same species in same area at same time May be sampled using randomized methods such as: quadrats, point-quarter (for sessile species) Mark-recapture (for motile species) is a function of 4 factors: Births and immigration add individuals to a population. PopuIation size Emigration Natality Immigration Deaths Deaths and emigration remove individuals from a population.

22 Population Size TOPIC C.5 POPULATION ECOLOGY May be sampled using randomized methods such as: quadrats, point-quarter (for sessile species) Mark-recapture (for motile species) Lincoln Index: Practice: 200 penguins captured, tagged, released One month later: 200 penguins captured, of which 20 were previously tagged Penguin pop =

23 Population Growth TOPIC C.5 POPULATION ECOLOGY What growth patterns are possible? J-curve Exponential Ideal conditions S-curve (sigmoid) Logistic Occurs as species approaches carrying capacity

24 TOPIC C.5 POPULATION ECOLOGY Limiting Factors Density Dependent Predation Food Resources Disease/Parasitism Waste toxicity Density Independent Natural disasters (fire, flood, ) Climate change N. American pika

25 TOPIC C.5 POPULATION ECOLOGY Limiting Factors Top Down or Bottom Up Predict the effect of human or physical factors adversely affecting secondary consumers

26 TOPIC C.5 POPULATION ECOLOGY Logistic growth Exponential growth phase Natality + Immigration >> Mortality + Emigration Plentiful resources Low environmental resistance Transitional phase Natality rate? Mortality rate? Growth rate? Plateau N + I = M + E

27 TOPIC C.5 POPULATION ECOLOGY Population Growth - application Algal bloom Sudden enrichment due to fertilizer runoff (eutrophication) Algae growth blocks light Phytoplankton? Aquatic plants? Respiration rate vs photosynthetic rate? Herbivores cannot keep up with algae growth Algae begin die off Bacterial decomposer pop size? Dissolved O 2?

28 TOPIC C.5 POPULATION ECOLOGY You are a Ranger and spot the beginning of an algal bloom in Odell Lake Bottom up control options? Top Down control options?