Global Enivronmental Issues: Biodiversity. What is Biodiversity? The total variability of life on earth

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1 Global Enivronmental Issues: Biodiversity What is Biodiversity? The total variability of life on earth Knowledge of biodiversity, its loss, patterns of loss and effects of that loss will provide us with a greater understanding of future threats to our livelihoods. Thus to think about Global Environmental issues and human effects on the environment is to understand how we contribute to species loss and the destruction of biodiversity across the globe. 1

2 US Department of Agriculture NATIONAL ORGANIC PROGRAM: Biodiversity Conservation operationalized FINALLY Biodiversity is the diversity of life existing at three levels: genetic, species, and ecosystem. Therefore biodiversity includes variety in all forms of life, from bacteria and fungi to grasses, ferns, trees, insects, and mammals. It encompasses the diversity found at all levels of organization, from genetic differences to the types of natural communities (groups of interacting species) found in a particular area. Biodiversity also includes the full range of natural processes upon which life depends, such as nutrient cycling, carbon and nitrogen fixation, predation, symbiosis and natural succession. Definition from the May 2009 NOSB recommendation. 2

3 Types of Biodiversity: Genetic Diversity variation within populations of animals measured in variation between genes or DNA sequences Species diversity alpha biodiversity : Diversity within a given place or area richness (number of species) versus evenness (relative abundance, question of species dominance) Ecological diversity community diversity, beta diversity, varience across space? landscape biodiversity gamma biodiversity 3

4 Where does diversity come from? 1. Evolutionary mechanisms produce biodiversity i. Variation ii. selection Human evolution and diversity: Views of evolution: Fig 1: Tree View of nature) versus Fig 2: Branching Bush (contemporary view) 4

5 History of biodiversity: 500 Million Years ago: the Cambrian Explosion The original fusion that made animal life possible!: diversitythrough-interaction symbiosis: Mitochondria as a symbiotic organism within the genome: powerhouse of the cell, Separate DNA, Permitted the rise of genetic complexity by allowing mitochondrial simplicity! 5

6 Where does Biodiversity come from? 2. Relations between species: coevolutionary relationships: mutualism, symbiosis, Allopathy Separation of species 6

7 Where does biodiversity come from 3. Biodiversity produced by landscapes-level interactions: Biodiversity in spatial heterogeneity: Guinea-Bissau Rainforest canopy coastline 7

8 BIODIVERSITY LOSS: Question of our age: Are humans causing the sixth great (anthropogenic) mass extinction? Are we on the verge of triggering a sixth worldwide collapse in species diversity? 8

9 i. species loss rates a. absolute loss 9

10 10

11 So what? why should we care about biodiversity? What has biodiversity done for me lately? a. beauty of biodiversity, the spice of life, children develop better when exposed to greater diversity, both microbiologically and psychologically. Diversity is beautiful! 11

12 b. Organisms provide important sources for medicines, fibers, materials: losing biodiversity means also a loss in access to important biologically active compounds 25% of medicines currently in use are plantbased 12

13 c. Biodiversity in number of crops increases total productivity by 10% by making better use of space: polycultures Genetic diversity in crop plants and plants increases the stability of both global and local food sources by protecting populations from diseases. 13

14 d. Preventing ecological collapse: how many species may be lost before the web of life begins to collapse? 14

15 e. Biodiversity provides environmental services Provisioning: Food, fiber, fuel, biologics Genetic Water and Air a bit of overlap, bottom line is that biodiversity provides many benefits Regulating: Invasion resistance and Pest control Pollination & Seed dispersal Climate regulation Stabilizing Ecosystem Intregrity Natural Hazards Cultural: Values Knowledge Recreation, tourism Sense of place Supporting: Habitat Nutrients and Soil O2 and CO2 sequestration 15

16 Biodiversity and risk: no reason to risk our planet by putting profit before ecological stability: We have plenty of food, fiber, and other items without expanding acreages under cultivation, stripping old-growth forests or drilling new oil wells and digging coal! We can t replace lost biodiversity 16

17 Issue: What level of biodiversity should be privileged? landscapes? genes? Species? What is the appropriate unit for conservation activities? 17

18 How do we measure biodiversity? Uncertainty is a central problem Numbers of species 1.75 million species scientifically identified. estimated 30 million species on earth. estimated 40,000 species rendered extinct annually. Biodiversity part 2 analyzing biodiversity 18

19 Issue: biodiversity hot spots: what is a biodiversity hot spot? how do types of biodiversity and processes of biodiversification create in hot spots? 19

20 Problems of Conservation 1: Balancing between human exploitation and habitat conservation Biodiversity part 3 Conservation Satellite Photo: Spread of farming 20

21 Problems of Conservation 2: separating background versus Proximate Causes: Where to best attack biodiversity loss? Background Proximate 21

22 Problems of conservation 3: how do we use our knowledge of biodiversity mechanisms to design workable conservation schemes? When we design conservation areas and policies How do we both mitigate and also focus on background causes? Mesoamerican bio-corridor 22

23 Issue: The politics of biodiversity = politics of knowledge Convention on Biodiversity: US agreed to measure biodiversity, but has limited funds to the US Biological Survey and HAS NOT signed the international Convention on Biological Diversity. Why? We would almost certainly find new species that would then be protected by the Endangered Species Act. 23

24 Review: 1. Biodiversity, what is it good for? a. Genetic Diversity Within Species: protecting from disease and permitting adaptation vulnerable Versus robust b. Species Diversity: stabilizing environments agroecological c. Ecological Diversity Web of Life: More connections = reduced likelihood of collapse 24

25 Review: 2. Biodiversity, Where is it? a. Problem of knowledge: measuring and surveying Species numbers movement b. Global Distribution Biodiversity hot spots 25

26 Non-Western Views of Biodiversity

27 Vandana Shiva: perspectives on Biodiversity Local systems approach Forestry and agriculture integrated Multidimensional outputs: wood, food, fodder, etc Productivity is understood to be multidimensional: has conservation effect Dominant systems approach Forestry separate from agriculture Each system 1-dimensional: food separate from forestry etc. Productivity is 1-dimensional, not related to conservation sustainable Non-sustainable 27

28 Local: Colonized; Indigenous/Co mmons Dominant: Colonial India/ Privatized

29 From Shiva: Monocultures of the Mind Local Tree: Native species used in Food and Forestry Eucalyptus Tree: (forestry species used in to replace native forests for industrial wood production)

30 So, how is this related to biodiversity? A different, but complementary theory of how biodiversity comes into being 30

31 All that is solid, Melts into air all that is holy is profaned, and [we are] at last compelled to face with sober senses [our] real conditions of life?? FIN 31

32 Issue 3: Distribution of populations and sampling problematic 32

33 Global Background Economic Drivers, what about the future? MAP: Biodiversity loss: 4 Scenarios for i. Markets unfettered ii. (growth) Policy-driven iii. (military) security driven iv. Sustainable economies United Nations environmental program Study 33

34 Design: biological corridors, species migrations, conservation butterflies whales birds 34

35 Issue 2: Scale and Geography: evenness versus dominance: oaks versus lilies. Patch versus Matrix: dimensions geometry: edge effects 35

36 Example: Distribution of Biodiversity in Africa: Biodiversity Differs By Group (e.g., birds, Plants, Mammals Each have Own biogeography 36

37 f. Finally, let s recollect again: Biodiversity isn t just out there but also in here! A concern for any environmental course: How to avoid the creation of artificial distinctions between the environment over there and humans in here? i. Biodiversity within: the human gut symbiosis of digestion and disease 90% of cells in human body are non-human play critical role in digestion and disease prevention ii. Food, air, allergens, environmental disease iii. Over-medication through antibiotics can promote ecological imbalance in the human intestine iv. CASE: Fecal transplants recent research on fecal transplants shows that some diseases may be cured by changing intestinal bacteria: weight-loss, cancer, 37 even autism? (I remain dubious on this one )

38 Examples of Biodiversity: 1) ancient (paleo) biodiversity 38