Ok, fine, but what IS an ecological community??

1. Biological Diversity Ok, fine, but what IS an ecological community??

2. Structural diversity

3. Functional diversity

4. Taxonomic Diversity: Species Richness Vs. Species Diversity

6. Most commonly used diversity measure: Shannon-Weaver Diversity Index aka Shannon-Weiner Diversity Index aka Shannon Index

7. Some general patterns of biodiversity

8. Some general patterns of biodiversity (in your book, figure19.12) Tree species richness as measured in 2.5°  2.5° quadrats across North America

9. Some general patterns of biodiversity (figure 19.6, in your book) The state of Wisconsin, showing the ecological divisions and provinces defined by Curtis

10. 19.2 Plant species richness along an elevational gradient in the Santa Catalina Mountains

11. Biodiversity concepts Concept # 1: Species –Area Relationship. Concept # 2: Alpha, Beta and Gamma Diversity Concept # 3:Disturbance – Diversity Relationship. Concept # 4:Productivity - Diversity Relationship. Concept # 5: Biodiversity- Ecosystem Function

12. Community properties: Species-Richness & Species Area Relationships

13. Biodiversity concepts Concept # 1: Species –Area Relationship. Concept # 2: Alpha, Beta and Gamma Diversity Concept # 3:Disturbance – Diversity Relationship. Concept # 4:Productivity - Diversity Relationship. Concept # 5: Biodiversity- Ecosystem Function

14. Alpha diversity, Beta and Gamma Diversity… Kinds of diversity….- alpha- beta - gamma

15. Biodiversity concepts Concept # 1: Species –Area Relationship. Concept # 2: Alpha, Beta and Gamma Diversity Concept # 3:Disturbance – Diversity Relationship. Concept # 4:Productivity - Diversity Relationship. Concept # 5: Biodiversity- Ecosystem Function

17. Biodiversity concepts Concept # 1: Species –Area Relationship. Concept # 2: Alpha, Beta and Gamma Diversity Concept # 3:Disturbance – Diversity Relationship. Concept # 4:Productivity - Diversity Relationship. Concept # 5: Biodiversity- Ecosystem Function

18. What is productivity? The concept of “productivity” in ecology is related to the use of the term in other fields such as agriculture, or even manufacturing. How much material is being produced in a site. In agriculture, you can easily measure the amount of some material coming from a site (e.g., and discuss the productivity of that site). In ecology, productivity is a bit more difficult to measure, and the general idea is the total volume of biomass (woody material, leaves, etc) that is being produced on a given site, during a given time frame. For productivity you need volume, area & time. One way to think about it is if you apply fertilizer to your lawn, that will probably cause the grass to grow faster. If you add fertilizer at different rates to different areas of the lawn and then clipped the grass, and measured the grass, you could get a sense of the amount of productivity in the law, and how it is influenced by the fertilizer. In ecosystems you can think about natural variation in productivity. If the site is protected from the sun, it might dry out less, and have more water and thus vegetation can grow faster. There are also gradients in soil fertility across the landscape. Often, ecologists will talk about “high productivity site” vs. a “low productivity site” and what they are talking about is, basically, a summation of all the factors that contribute to plant growth on a particular site. Some species do better on low productivity sites. Some do better on high productivity sites.

19. Okay then….what about diversity and productivity? The question has arisenconcept of “productivity” in ecology is related to the use of the term in other fields such as agriculture, or even manufacturing. How much material is being produced in a site. In agriculture, you can easily measure the amount of some material coming from a site (e.g., and discuss the productivity of that site). In ecology, productivity is a bit more difficult to measure, and the general idea is the total volume of biomass (woody material, leaves, etc) that is being produced on a given site, during a given time frame. For productivity you need volume, area & time. One way to think about it is if you apply fertilizer to your lawn, that will probably cause the grass to grow faster. If you add fertilizer at different rates to different areas of the lawn and then clipped the grass, and measured the grass, you could get a sense of the amount of productivity in the law, and how it is influenced by the fertilizer. In ecosystems you can think about natural variation in productivity. If the site is protected from the sun, it might dry out less, and have more water and thus vegetation can grow faster. There are also gradients in soil fertility across the landscape. Often, ecologists will talk about “high productivity site” vs. a “low productivity site” and what they are talking about is, basically, a summation of all the factors that contribute to plant growth on a particular site. Some species do better on low productivity sites. Some do better on high productivity sites.

20. 13.8 The relationship between productivity and species richness can have different shapes in different communities Why? One idea- at low levels of productivity (~nutrient availability) not many species can persist. As productivity increases, more species can live in the site

21. 13.8 The relationship between productivity and species richness can have different shapes in different communities Why? As you increase the level of productivity, some species, that are the best competitors, will become dominant. They can eliminate some other species

22. 13.8 The relationship between productivity and species richness can have different shapes in different communities • Why? • If you put these two ideas together, you get a unimodal relationship

23. 13.7 Experimental fertilization of 72 plots in an old field in NW Pennsylvania (Part 1) Concept # 1: Influence of local productivity on local patterns of biodiversity. Hump-backed productivity-diversity curve.

24. Diversity

25. McEwan data. Herbaceous species in a temperate, old-growth forest. L

26. 13.9 Percentage of studies showing various relationships (Part 1)

27. 19.5 Percentage of studies showing various relationships between productivity and vascular plant species richness at different geographic scales

28. How do disturbance and productivity relate to one another as predictors of biodiversity?

29. How do disturbance and productivity relate to one another? The Dynamic Equilibrium Model of diversity of Huston (1979). You read this figure like a topographic map, where the orange is the peak. So there is a peak in diversity at intermediate levels of both diversity and productivity. In restoration projects you may have gradients in both productivity and diversity.

30. Biodiversity concepts Concept # 1: Species –Area Relationship. Concept # 2: Alpha, Beta and Gamma Diversity Concept # 3:Disturbance – Diversity Relationship. Concept # 4:Productivity - Diversity Relationship. Concept # 5: Biodiversity- Ecosystem Function

31. Biodiversity- Ecosystem Function Relationship Is there a generalized relationship between diversity and ecosystem function in restoration?

32. Concepts Niche Complementarity: This is an idea about the relationship among species in creating or perpetuating some ecosystem property. One way to illustrate this is to think about species fitting together sort of like puzzle pieces. As you add species the picture gets clearer…in the analogy, as you add species to the ecosystem, its functionality increases accordingly. One example that is currently ‘hot’ is the idea that as you add tree species to a forest, that forest’s capacity to capture and sequester carbon increases. This concept carries a whole load of assumptions with it…and it certainly has not been clearly proven for all systems and/or all ecosystem functions. If Niche Complementarity is occurring, you would expect a linear relationships between the function and species diversity- as you add species- the function linearly increases. One outstanding issue is whether apparent (NC) is because of increasingly filled niche space or whether you just happen to pick up a species that is good at that particular job as you add species (aka, Sampling Effect). This issue is very much alive in Ecology right now.

33. Concepts Functional Groups: There are a lot of species in the world. A LOT. In many cases it is very difficult, if not impossible, to address this diversity from a scientific perspective, much less from the perspective of management. One way to simplify this diversity is to focus on an individual’s functions, rather than its taxonomy (i.e., its evolutionary relationship to other organisms). If you can “bin” species depending on function then management or restoration could, potentially, focus on functional groups. Some examples include “vernal herbs,” and nitrogen fixing plangs

34. Concepts Species Redundancy: If we think about species as functional participants in ecosystems- providing a specific capacity/outcome/function, it can lead to the idea that some (or maybe even many) species are providing identica l, or at least measurably similar, attributes to the system. Thus, the idea of species redundancy. But, don’t think of this in a negative context…like there are useless species in an ecosystem. Instead, thinking about it from this perspective allows the identification of species that are MORE crucial to preserve/restore…those that provide a specific function when no other species do. Some examples, for instance, N-fixing plants, or maybe a shredding insect. From a biodiversity management perspective one goal me be create or maintain redundancy, to make the ecosystem more stable.

35. Biodiversity, ecosystem function, and functional diversity, some ideas…

36. Biodiversity- Ecosystem Function Relationship Is there a generalized relationship between diversity and ecosystem function?

37. Hooper, David U., and Peter M. Vitousek. "The effects of plant composition and diversity on ecosystem processes." Science 277.5330 (1997): 1302-1305.

38. biodiversity