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Energy Money Peak Oil Land Food Water SewageSpace Travel
Spring 2015 electronic CIS course-instructor survey period begins Monday, April 27th, and runs until May 8th
Third Exam Thursday 7 May 2015Chapters 11-15, 17-18 plus 8 readings
11-1230 AM Final Exam15 May 2015, 2-5 PMWelch 2.246
1230-2 PM Final Exam18 May 2015, 9-12 AMWelch 2.308
Community and Ecosystem Ecology
Macrodescriptors = Aggregate Variables
Compartment models, trophic structure, food webs,
connectance, rates of energy fixation and flow,
biogeochemical cycles, ecological energetics,
ecological efficiency, trophic continuum, guild structure,
ecological pyramids, successional stages, transition
matrix, regional, local. and point diversity,
saturation with species, species diversity, equitability,
relative importance curves, latitudinal gradients in diversity,
Latitudinal gradients in diversity Time theories, degree of saturation with species
Climatic stability and climatic predictability, niche breadth
Spatial heterogeneity, range of available resources
Productivity and stability of productivity
Competition —> specialization, narrow niches, higher diversity
Disturbance, intermediate disturbance hypothesis, niche overlap
Predation-induced diversity (Paine’s Pisaster experiment)
Latitudinal gradients in species diversityTropical tree species diversitySeeding ringsNutrient mosaicCircular networksDisturbance (epiphyte loads)Sea otters as keystone species, alternative stable statesTypes of stabilityConstancy = variabilityInertia = resistanceElasticity = resilience (Lyapunov stability)Amplitude (domain of attraction)Cyclic stability (neutral stability, limit cycles, strange attractors)Trajectory stability (succession)Traditional ecological wisdom: diversity begats stability
Seed Predation Hypothesis
Nutrient Mosaic Hypothesis
Circular Networks Hypothesis
Disturbance Hypothesis
(Epiphyte Load Hypothesis)
Tree Species Diversity in Tropical Rain Forests
Amchitka ShemyaSea Otters 20-30 km2 only vagrantsKelp dense mats heavily grazedSea Urchins 8/m2, 2-34mm 78/m2, 2-86mmChitons 1/m2 38/m2
Barnacles 5/m2 1215/m2
Mussels 4/m2 722/m2
Greenling abundant scarce or absentHarbor Seals 8/km l.5-2/kmBald Eagles abundant scarce or absent
Community Stability
Traditional Ecological Wisdom
Diversity begats stability (Charles Elton)
More complex ecosystems with more
species have more checks and balances
Alternative stable stateshttp://www.nature.com/scitable/knowledge/library/alternative-stable-states-78274277
Types of Stability
Point Attractors <——> Repellers
Domains of Attraction, Multiple Stable States
Local Stability <——> Global Stability
Types of Stability
1. Persistence
2. Constancy = variability
3. Resistance = inertia
4. Resilience = elasticity (rate of return, Lyapunov stability)
5. Amplitude stability (Domain of attraction)
6. Cyclic stability, neutral stability, limit cycles, strange attractors
7. Trajectory stability
Edward Lorenz
Strange Attractor
“Butterfly Effect”
dx/dt = a(y - x)
dy/dt = bx - y - xz
dz/dt = yz – cz
Traditional Ecological Wisdom:Diversity begats Stability
MacArthur’s idea
Stability of an ecosystem should increase with both the number of different trophic links between species and with the equitability of energy flow up various food chains
Robert May challenged conventional ecological thinking and asserted that complex ecological systems were likely to be less stable than simpler systems
May analyzed sets of randomly assembled Model Ecosystems. Jacobian matrices wereAssembled as follows: diagonal elements were defined as – 1. All other interaction terms were equally likely to be + or – (chosen from a uniform random distribution ranging from +1 to –1). Thus 25% of interactions were mutualisms, 25% were direct interspecific competitors and 50% were prey-predator or parasite-host interactions. Not known for any real ecological system!
May varied three aspects of community complexity:
1.Number of species (dimensionality of the Jacobian matrix)
2. Average absolute magnitude of elements (interaction strength)
3.Proportion of elements that were non-zero (connectedness)
May’s challenge using random model systems
Real systems not constructed randomly
Real communities are far from random in construction, but must obey various constraints.Can be no more than 5-7 trophic levels, food chain loops are disallowed, must be at least one producer in every ecosystem, etc.
Astronomically large numbers of random systems : for only 40 species, there are 10764 possible networksof which only about 10500 are biologically reasonable — realistic systems are so sparse that random sampling is unlikely to find them. For just a 20 species network, if one million hypothetical networks were generated on a computer every second for ten years, among the resulting 31.513 random systems produced, there is a 95% expectation of never encountering even one realistic ecological system!
Conservation Biology bridges the gap between naturalsciences and social sciences. It is applied ethical biology.
Conservation Biology
Recognition and management
of endangered species
Design of nature reserves
Restoration ecology
Ecosystem conservation
Ecological economics
Environmental ethics
“Wildlife Management” is a sad joke —>
We humans cannot even manage our
own populations
Conservation Biology
Value of Biodiversity
Hot spots of diversity
SLOSS debate, Design of Nature Reserves
Minimum viable population size
Genetic bottleneck
Population viability analysis
Sensitivity analyses of Leslie matrices
“Extinction vortex”
Habitat loss, habitat fragmentation,
small population size,
genetic and demographic stochasticity,
toxic pollution and climatic changes
Norman Myers“40% of Earth’sspecies could besaved by protecting1.4% of its surface”
No facts, only interpretations: “Sunrise” = Spinup = SpindawnSelective thinking, use classical Darwinian natural selectionAvoid homicidal males, ages 15 to 40-ishDon’t trust politicians (self deceit, better liars)Don’t trust anybody, not even your mate (cuckoldry, promiscuity)Wash your hands and keep them away from your face!Remember how to get into and out of a public toiletHost-altered behavior: STDs —> increased sexual activity?Eat green and brown bugs and caterpillars, not red or yellow onesSoak acorns before eating, save tannin water for tanning hidesRemember you can make soap by boiling animal fat and ashesChew on willow for pain relief (salicyclic acid)Don’t stand still around a big monitor lizard — if one starts to run upyour back, don’t reach around to get it off, just lay down on your bellyKnock centipedes off in the direction they are moving
Largest Mustelid: Wolverine, Gulo gulo (= glutton) and Gulo luscus
(one-eyed glutton), common names “skunk-bear” and “carcajou”
Largest Mustelid: Wolverine, Gulo gulo and Gulo luscus, now
extinct over most of its range, fur used for parkas repels ice “rime”
FOR THE LAST WOLVERINE
They will soon be down To one,
but he still will be For a little while
still will be stopping The flakes in the air with a look,
Surrounding himself with the silence Of whitening snarls.
Let him eat The last red meal of the condemned
To extinction, tearing the guts from an elk.
James Dickey
Yet that is not enough For me.
I would have him eat The heart, and, from it,
have an idea Stream into his gnawing head
That he no longer has a thing To lose,
and so can walk Out into the open,
in the full Pale of the sub-Arctic sun
Where a single spruce tree is dying
Higher and higher. Let him climb it
With all his meanness and strength.
Lord, we have come to the end Of this kind of vision of heaven,
As the sky breaks open Its fans around him and shimmers
And into its northern gates he rises
Snarling complete in the joy of a weasel
With an elk’s horned heart in his stomach
Looking straight into the eternal Blue, where he hauls his kind.
I would have it all My way: at the top of that tree I place
The New World’s last eagle Hunched in mangy feathers
giving Up on the theory of flight.
Dear God of the wildness of poetry,
let them mate To the death in the rotten branches,
Let the tree sway and burst into flame
And mingle them, crackling with feathers,In crownfire.
Let something come Of it something gigantic legendary
Rise beyond reason over hills Of ice
SCREAMING that it cannot die, That it has come back,
this time On wings, and will spare no earthly thing:
That it will hover, made purely of northern Lights, at dusk
Dear God of the wildness of poetry,
let them mate To the death in the rotten branches,
Let the tree sway and burst into flame
And mingle them, crackling with feathers,In crownfire.
Let something come Of it something gigantic legendary
Rise beyond reason over hills Of ice
SCREAMING that it cannot die, That it has come back,
this time On wings, and will spare no earthly thing:
That it will hover, made purely of northern Lights, at dusk
and fall On men building roads:
will perchOn the moose’s horn like a falcon Riding into battle
into holy war against Screaming railroad crews:
will pull Whole traplines like fibers from the snow
In the long-jawed night of fur trappers.
But, small, filthy, unwinged, You will soon be crouching Alone,
with maybe some dim racial notion Of being the last,
but none of how much Your unnoticed going will mean:
How much the timid poem needs
The mindless explosion of your rage,
The glutton’s internal fire
the elk’s Heart in the belly, sprouting wings,
The pact of the “blind swallowing Thing,” with himself,
to eat The world, and not to be driven off it
Until it is gone, even if it takes Forever.
I take you as you are And make of you what I will,
Skunk-bear, carcajou, bloodthirsty Non-survivor.
Lord, let me die but not die
Out.
Copyright © 1966 by James Dickey