1. Ecology and the Environment (Chapter 22) Background and Historical Development Background and Historical Development Attributes of Ecological Systems Attributes of Ecological Systems Selected Issues – Applied Ecology Selected Issues – Applied Ecology Take Home Messages Take Home Messages

2. Take-Home Messages Functional unit in ecology is the ecosystem; it is analogous to the cell Functional unit in ecology is the ecosystem; it is analogous to the cell Hierarchy theory and emergent properties is applicable to the study of ecology Hierarchy theory and emergent properties is applicable to the study of ecology Energetics of ecosystems is driven by (i) principles of thermodynamics (1 st and 2 nd Laws) and (ii) nature in which organisms acquire and utilize energy; result is a predictable pattern among all ecosystems embodied in the concept of trophic levels Energetics of ecosystems is driven by (i) principles of thermodynamics (1 st and 2 nd Laws) and (ii) nature in which organisms acquire and utilize energy; result is a predictable pattern among all ecosystems embodied in the concept of trophic levels Ecosystems are not static but change over time in predictable and recurrent ways; this change is called succession Ecosystems are not static but change over time in predictable and recurrent ways; this change is called succession Energy passes through ecosystems unidirectionally, whereas elements/materials cycle throughout ecosystems Energy passes through ecosystems unidirectionally, whereas elements/materials cycle throughout ecosystems Biodiversity, the number and distribution of species, is an important feature of ecosystems Biodiversity, the number and distribution of species, is an important feature of ecosystems

3. Ecologyand the Environment Background and Historical Development Background and Historical Development Attributes of Ecological Systems Attributes of Ecological Systems Selected Issues – Applied Ecology Selected Issues – Applied Ecology Take Home Messages Take Home Messages

4. Background and Historical Context Discipline of ecology Discipline of ecology Evolution of the science Evolution of the science Orientation by type of system Orientation by type of system

5. Discipline 1950’s: emergence of the discipline 1950’s: emergence of the discipline Stimulus: technological changes Stimulus: technological changes Harnessing the atom (radioactive elements) Harnessing the atom (radioactive elements) Rachel Carson’s Silent Spring Rachel Carson’s Silent Spring Two sub-disciplines Two sub-disciplines Basic ecology Basic ecology Structure and function of ecosystems Structure and function of ecosystems Applied ecology Applied ecology Human-altered and “managed” ecosystems Human-altered and “managed” ecosystems

6. Evolution Early to mid 1900 Early to mid 1900 descriptive natural history descriptive natural history > 1950’s > 1950’s Experimentally and hypothesis driven research Experimentally and hypothesis driven research > 2000 > 2000 Experimentally and hypothesis driven research Experimentally and hypothesis driven research Mathematical modeling at a global scale Mathematical modeling at a global scale

7. Types of Ecosystems Natural ecosystems Natural ecosystems Grasslands, unmanaged forests, wetlands, rivers, etc. Grasslands, unmanaged forests, wetlands, rivers, etc. Key: ecological systems that are largely unmanaged for human use Key: ecological systems that are largely unmanaged for human use Human-dominated ecological systems Human-dominated ecological systems Agroecosystems, managed forest (timber), fish farms, urban/suburban landscapes, etc. Agroecosystems, managed forest (timber), fish farms, urban/suburban landscapes, etc. Key: ecosystems that are harvested by humans and are subsidized (fertilizer, water, pest management, etc.) Key: ecosystems that are harvested by humans and are subsidized (fertilizer, water, pest management, etc.) Attributes in common Attributes in common Same basic structure and function (principles are the same) Same basic structure and function (principles are the same)

8. Attributes Ecosystem (ecological system) Ecosystem (ecological system) Hierarchy theory and emergent properties Hierarchy theory and emergent properties Structure of ecosystems Structure of ecosystems Energetics of ecosystems (flow of energy) Energetics of ecosystems (flow of energy) Biodiversity Biodiversity Cycles of materials and elements Cycles of materials and elements

9. Ecology Background and Historical Development Background and Historical Development Attributes of Ecological Systems Attributes of Ecological Systems Selected Issues – Applied Ecology Selected Issues – Applied Ecology Take Home Messages Take Home Messages

10. Attributes Ecosystem Ecosystem Hierarchy theory and emergent properties Hierarchy theory and emergent properties Structure of ecosystems Structure of ecosystems Energetics of ecosystems (flow of energy) Energetics of ecosystems (flow of energy) Biodiversity Biodiversity Cycles of materials and elements Cycles of materials and elements

11. Ecosystems Ecological systems – ecosystem Ecological systems – ecosystem Components Components Biotic components Biotic components All living organisms – plants, animals and microbes All living organisms – plants, animals and microbes Abiotic components Abiotic components All non-living components – soil, atmosphere, water, climate, etc. All non-living components – soil, atmosphere, water, climate, etc. Ecosystem Ecosystem Fundamental unit of ecology; analogous to that of the cell Fundamental unit of ecology; analogous to that of the cell

12. Hierarchy Theory and Emergent Properties EarthBiosphereBiomeEcosystemCommunityPopulationOrganisms

13. Terms Population: assemblage of individuals of the same species in the same area Population: assemblage of individuals of the same species in the same area Community: assemblage of all species in a given area Community: assemblage of all species in a given area Biome: large regional units of several different types of ecosystems existing in same general area Biome: large regional units of several different types of ecosystems existing in same general area Biosphere: all of the Earth’s biomes at the global scale (shuttle frame of reference) Biosphere: all of the Earth’s biomes at the global scale (shuttle frame of reference)

14. Major Biomes

15. Emergent Properties Hierarchy theory and emergent properties Hierarchy theory and emergent properties Relate to ecology Relate to ecology Emergent properties Emergent properties Water (combination of H and O) Water (combination of H and O) Sodium chloride (combination of Na and Cl) Sodium chloride (combination of Na and Cl) Mixes species forest (combination of 50+ different species of trees, shrubs, microbes and animals) Mixes species forest (combination of 50+ different species of trees, shrubs, microbes and animals) Unanticipated properties Unanticipated properties

16. Attributes Ecosystem (ecological system) Ecosystem (ecological system) Hierarchy theory and emergent properties Hierarchy theory and emergent properties Structure of ecosystems Structure of ecosystems Energetics of ecosystems (flow of energy) Energetics of ecosystems (flow of energy) Biodiversity Biodiversity Cycles of materials and elements Cycles of materials and elements

17. Structure of Ecosystems Structure is underpinned by flow of energy Structure is underpinned by flow of energy Autotrophs: fix energy from sun - plants Autotrophs: fix energy from sun - plants Heterotrophs: consume energy in C-C bonds Heterotrophs: consume energy in C-C bonds Primary consumers - herbivores Primary consumers - herbivores Secondary consumers – carnivores and omnivores Secondary consumers – carnivores and omnivores Tertiary consumers – saprovores (dead organic matter) Tertiary consumers – saprovores (dead organic matter) All organisms are classified by their source of energy All organisms are classified by their source of energy

18. Trophic Levels of an Ecosystem

19. Attributes Ecosystem (ecological system) Ecosystem (ecological system) Hierarchy theory and emergent properties Hierarchy theory and emergent properties Structure of ecosystems Structure of ecosystems Energetics of ecosystems (flow of energy) Energetics of ecosystems (flow of energy) Biodiversity Biodiversity Cycles of materials and elements Cycles of materials and elements

20. Energetics of Ecosystems Common theme/attribute to all ecosystems Common theme/attribute to all ecosystems Linkage to physics Linkage to physics 1 st Law of Thermodynamics (conservation) 1 st Law of Thermodynamics (conservation) 2 nd Law of Thermodynamics (entropy increases) 2 nd Law of Thermodynamics (entropy increases) Highly order state of all ecosystems is function of transforming energy in trophic structure Highly order state of all ecosystems is function of transforming energy in trophic structure Thermodynamics: dissipation of energy is most common in form of heat and respiration Thermodynamics: dissipation of energy is most common in form of heat and respiration

21. Keys to Energetics Energy flows through ecosystems unidirectionally Energy flows through ecosystems unidirectionally As energy flows, amount of energy available to do work (potential energy in C-C bonds) decreases As energy flows, amount of energy available to do work (potential energy in C-C bonds) decreases Flow of energy places constraints on the number of organisms that can exist in higher trophic levels Flow of energy places constraints on the number of organisms that can exist in higher trophic levels

22. Quantification of Energy Flow Sun Autotrophs 1 0 Consumers 2 nd Consumers 3 0 Consumers 1% 10% Respiration and heat

24. Trophic Levels of an Ecosystem

25. Attributes Ecosystem (ecological system) Ecosystem (ecological system) Hierarchy theory and emergent properties Hierarchy theory and emergent properties Structure of ecosystems Structure of ecosystems Energetics of ecosystems (flow of energy) Energetics of ecosystems (flow of energy) Biodiversity Biodiversity Cycles of materials and elements Cycles of materials and elements

26. Biodiversity Diversity of world’s biota: ~100 Million species, of which 1.5 Million have been catalogued Diversity of world’s biota: ~100 Million species, of which 1.5 Million have been catalogued Biodiversity: measurement of the diversity of flora, fauna and microbes Biodiversity: measurement of the diversity of flora, fauna and microbes Species richness (number of species) Species richness (number of species)

27. Biodiversity

28. Biodiversity: Arid Landscaspes

29. Biodiversity: Significance Humanistically: intuitively value (appreciate diversity of life forms) Humanistically: intuitively value (appreciate diversity of life forms) Ecologically: evidence that biodiversity is related to stability and functioning of ecosystems Ecologically: evidence that biodiversity is related to stability and functioning of ecosystems Declining biodiversity with human population Declining biodiversity with human population

30. Attributes Ecosystem (ecological system) Ecosystem (ecological system) Hierarchy theory and emergent properties Hierarchy theory and emergent properties Structure of ecosystems Structure of ecosystems Energetics of ecosystems (flow of energy) Energetics of ecosystems (flow of energy) Biodiversity Biodiversity Cycles of materials and elements Cycles of materials and elements

31. Cycling of Elements and Materials Unlike energy, elements and materials cycle throughout ecosystems and they are re-used Unlike energy, elements and materials cycle throughout ecosystems and they are re-used Examples: water, carbon, nitrogen Examples: water, carbon, nitrogen Path is commonly circular passing from biosphere to geosphere to hydrosphere to atmosphere Path is commonly circular passing from biosphere to geosphere to hydrosphere to atmosphere

32. Basic Cycling Model Atmosphere Biosphere Hydrosphere Geosphere

33. Cycling of Elements: Nitrogen

34. Ecology Background and Historical Development Background and Historical Development Attributes of Ecological Systems Attributes of Ecological Systems Selected Issues – Applied Ecology Selected Issues – Applied Ecology Take Home Messages Take Home Messages

35. o Human Population Growth

36. Selected Issues in Ecology Acid rain Acid rain Biodiversity and habitat loss Biodiversity and habitat loss Climate change – a global issue Climate change – a global issue Ozone and particulate matter in the atmosphere Ozone and particulate matter in the atmosphere Stratospheric ozone and UV-B radiation Stratospheric ozone and UV-B radiation Tropospheric ozone and human health Tropospheric ozone and human health PM and human health PM and human health

37. Take-Home Messages Functional unit in ecology is the ecosystem; it is analogous to the cell Functional unit in ecology is the ecosystem; it is analogous to the cell Hierarchy theory and emergent properties is applicable to the study of ecology Hierarchy theory and emergent properties is applicable to the study of ecology Energetics of ecosystems is driven by (i) principles of thermodynamics (1 st and 2 nd Laws) and (ii) nature in which organisms acquire and utilize energy; result is a predictable pattern among all ecosystems embodied in the concept of trophic levels Energetics of ecosystems is driven by (i) principles of thermodynamics (1 st and 2 nd Laws) and (ii) nature in which organisms acquire and utilize energy; result is a predictable pattern among all ecosystems embodied in the concept of trophic levels Ecosystems are not static but change over time in predictable and recurrent ways; this change is called succession Ecosystems are not static but change over time in predictable and recurrent ways; this change is called succession Energy passes through ecosystems unidirectionally, whereas elements/materials cycle throughout ecosystems Energy passes through ecosystems unidirectionally, whereas elements/materials cycle throughout ecosystems Biodiversity, the number and distribution of species, is an important feature of ecosystems Biodiversity, the number and distribution of species, is an important feature of ecosystems