Lecture Notes - Biodiversity 1 - Dec 2nd

The buzzword for the lecture is ecosystem based management (EBM)
The chances of coming up with a new large mammal species is extremely unlikely, but it does happen.
¼ of the animal species of the world are beetles. The creator had an inordinate fondness for beetles – quote from same guy as “I would jump in the river for my brother or for 3 cousins.
Best estimates of named and unnamed species.
What does it really matter if we lose a species here or there? Do you care more about losing species or should you really be worried about families and phyla?
There’s a core community of species that occupy an ecosystem most of the time.
Contour map of tree species richness.
There is not perfect explanation for the latittudinal diversity gradient. Warmth, moisture has something to do with it. People go to the tripcis to dsee the diversity represented there.
Norman Meyers originated this idea. We set out to identify locations with the greatest spots of diversity.
Remote islands are not easily colonized over water from other land masses. On islands that are host to a loan species
In general if you have species diversity you have functional diversity.
There is a predictable relationship between the amount of area sampled and the amount of species diversity found -> greater habitats, greater sample size. More area = more habitats.
For the same level of productivity an environment with higher complexity holds more species. – more complex habitat holds more species.
As you include larger areas, you are including greater habitat diversity. Beta
Alpha and beta diversity are greater as you go further south.
You can be pretty sure on a small island how big it is and whether or not you have counted all the species. As species colonize the island the rate of colonization will decline. As you add species to the island there are fewer and fewer to go there. When there is a low level of colonization there is also a low level of extinction. No species = no extinction.
Based on the findings that big islands have more species than small islands…
For a given number of species, small islands are more likely to have a higher rate of exctinction. The number of species in an area is a function of the balance between colonization and extinction.
This shows the results of an experiment where the fumigated several islands and then tested how quickly the species representation returned through colonization and reached its equilibrium.

289 plots, each 169 m2, were planted and weeded to have either 0, 1, 2, 4, 8, 16, or 32 perennial savanna-grassland species representing 0, 1, 2, 3, 4, or 5 plant functional groups.
Grassland-savanna plants were classified into functional groups on the basis of intrinsic physiological and morphological differences, which influence differences in resource requirements, seasonality of growth, and life history.
1) Legumes fix nitrogen, the major limiting nutrient at our site (7).
2) Grasses with the three-carbon photosynthetic pathway (C3) grow best during the cool seasons and have higher tissue N than do
3) grasses with the C4 pathway, which grow best during the warm season.
4) Woody plants have high allocation to perennial stem and low growth rates
5) forbs do not fix N and often have high allocation to seed.

A migratory, detritus-feeding fish modulates carbon flow and ecosystem metabolism in a hyperdiverse neotropical stream.
Increased standing crop of POC in Prochilodus removal section
Decreased downstream flux of POC due to reduced bioturbation and consumption, longer residence time
Increased heterotrophic respiration due to biofilm growth
Doubling of primary production
Because R increased more than P, P/R decreased in fish removal
Deficit in net ecosystem metabolism (P – CR) increased

Take-home messages
Biodiversity supports ecosystem services
Provisioning, regulating, cultural, supporting
Both diversity and redundancy have value
Current valuation typically excludes services, option and intrinsic values
Unsustainable practices often are enabled by subsidies, private ownership, immediate benefits
A fuller valuation can show benefits of sustainable practices

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