Upload
muneeb-arshad
View
215
Download
0
Embed Size (px)
Citation preview
8/18/2019 Biol 201 Lecture 19 Communities_2
1/9
3/20/20
Communities: who, how many,
and how do they interact?
What is community ecology?
The Python Challenge in Florida
Keystone species
Succession
Impacts of Brown Tree Snake Invasion in Guam
• Extirpation of 8 of 11 species of native
forest birds
• Decimated other vertebrate species,
including flying fox (a bat) and half oflizard species
• Dramatically altered existing food
webs
(Wiles et al., 2003)
Collapse of native birdsWhat is community ecology?
1. Why do some areas have many more
species than others?
2. Why are some species common while
others are rare?
3. How do the species interact?
What is community ecology?
4. Are some species more important than others
in structuring the community?
5. What will happen when a new species is
introduced?
6. Why and how do communities change
through time and across space?
What species are there? Species Richness.
Step 1 of being a community ecologist:
Figure out what species are in the community.
http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=KSIb6zTYnS2aPM&tbnid=4PBU-daOVhM1lM:&ved=0CAUQjRw&url=http://sensingnature.co.uk/education/176-2/&ei=nsI3UceOHoOzqQGul4CACg&psig=AFQjCNGohpPJsLTgKgW9e-P7U-DcmOUpGA&ust=1362695147477399http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=QoiSZMdNsEem5M&tbnid=oVriTrfI4aMUfM:&ved=0CAUQjRw&url=http://geographywiki.wikispaces.com/Don+Pipping&ei=OsI3Ub-RGMTErQHixYGoAg&psig=AFQjCNGyIXqCgcpUV4qIhcuFivGJYsaBJA&ust=1362695081069445http://en.wikipedia.org/wiki/File:Snake_browntree.jpghttp://en.wikipedia.org/wiki/File:Boiga_irregularis_coiled.jpg
8/18/2019 Biol 201 Lecture 19 Communities_2
2/9
3/20/20
Species richnessRichness: (S)
a count of the number
of species present in
an area.
TREES
Species richnessWhite spruce
Trembling asp en
Balsam poplar
Ponderosa pine
White spruce
Douglas Fir
Whitebark pine
Western larch
Lodgepole pine
Black cottonwood
Trembling aspen
Silver fir
Grand fir
Subalpine fir
Paper birch
Western redcedar
Mountain alder
Engelmann spruce
Western white pine
Black spruce
Douglas maple
Green alder
Sitka alder
Water birch
. . .and more. . .
3 species
~65 species
How many of each species are there?
Species evenness, diversity indices, dominantsStep 2 of being a community ecologist:
Figure out how many of each species are in the community.
(yep, big task is how to count things).
pitfall trap for dung beetles
How common are the different species?
Dominance and evenness
Durães et al. 2005. Neotropical Entomology 34:721-731
Dominance and evenness: there’s math
for that
Simpson’s Diversity Index
D = Σ(ni/N)2
ni = number of individuals of species i
N = number of individuals of all species
D close to 1 : one species dominates
D close to 0 : few individuals each of
many species (more even)
http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=0RFFdHsjopNM1M&tbnid=JP8hicsZs7J83M:&ved=0CAUQjRw&url=http://sites.sinauer.com/ecology2e/ccc23.1.html&ei=D7g3Uc68PIaAqgGaroDoCQ&bvm=bv.43287494,d.aWM&psig=AFQjCNHliyFf9J4ehRGGwIhFwgdqqNFr4g&ust=1362692490670692http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=W3-uoGd_IeOyQM&tbnid=0ab3HC8aOocyJM:&ved=0CAUQjRw&url=http://www.coleoptera-neotropical.org/paginas/2_PAISES/Argentina/scarab_arg.html&ei=OcE3UfTnMIXyqAGokIHQBA&psig=AFQjCNHgSpEB_7szT1_FfwL7N2bTRG3voA&ust=1362694827369509http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=T1ajYLX8JW99pM&tbnid=jqM-U41LdI5INM:&ved=0CAUQjRw&url=http://www.americaninsects.net/b/canthon-sp-6-spot.html&ei=D783UYaJGoaCrAHB5YCIDQ&psig=AFQjCNH4gRCTJZQ5qQ597RjtYqw9-LA0Hw&ust=1362694281596251http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=PLcynUuDNEFw6M&tbnid=-_1cMhF3C8e8fM:&ved=0CAUQjRw&url=http://www.flickriver.com/photos/botalex/tags/beetle/&ei=t743UYOzCY75qAGxzoDACw&psig=AFQjCNG5L_vHdtMeUTl9jdS2j9Z_Bl6RCg&ust=1362694184437334http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=yaWz_c8T73RbPM&tbnid=kjfBbsy2-B1m8M:&ved=0CAUQjRw&url=http://www.scielo.br/scielo.php?pid=S1519-566X2005000500003&script=sci_arttext&ei=Qb03Ue74DsaiqQGh6IDIDg&psig=AFQjCNH1dyhJn7v4UxM02lQfu3c9c0-bUA&ust=1362693798649516http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=y3a6BGRviriepM&tbnid=86aXMzBUOxNu0M:&ved=0CAUQjRw&url=http://www.amentsoc.org/publications/bulletin/articles/dung-beetles-of-ayrshire.html&ei=V8M3Ub7hOMiorAHVkYGoDA&psig=AFQjCNEHzdVZYEnEme1LNsQtwAPaV-mQIA&ust=1362695287694157http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=0RFFdHsjopNM1M&tbnid=JP8hicsZs7J83M:&ved=0CAUQjRw&url=http://sites.sinauer.com/ecology2e/ccc23.1.html&ei=D7g3Uc68PIaAqgGaroDoCQ&bvm=bv.43287494,d.aWM&psig=AFQjCNHliyFf9J4ehRGGwIhFwgdqqNFr4g&ust=1362692490670692http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=0RFFdHsjopNM1M&tbnid=JP8hicsZs7J83M:&ved=0CAUQjRw&url=http://sites.sinauer.com/ecology2e/ccc23.1.html&ei=D7g3Uc68PIaAqgGaroDoCQ&bvm=bv.43287494,d.aWM&psig=AFQjCNHliyFf9J4ehRGGwIhFwgdqqNFr4g&ust=1362692490670692
8/18/2019 Biol 201 Lecture 19 Communities_2
3/9
3/20/20
Dominance and evenness: simple examples
D = Σ(ni/N)2
Species 1 33 97 60
Species 2 33 2 30
Species 3 34 1 10
=
(33/100)2
+(33/100)2
+(34/100)2
=0.33
=
(97/100)2
+(2/100)2
+(1/100)2
=0.94
=
(60/100)2
+(30/100)2
+(10/100)2
=0.46
Communities: how do they interact?
Step 3 of being a community ecologist:
Figure out how species in the community interact.
Limpkin
Florida panther
Key largo woodrat
Wood stork
Grey fox
Example 2: The Python Challenge
Burmese pythons (Python molurus bivitattus)
are invading Florida (pet releases and subsequent breeding)
Pythons can
reach 7 m, 90 kg
(a few near 200 kg!)
They constrict
(suffocate) their prey.
Native to SE Asia.
Background to the python problem
>1 million constrictors (9 species) imported
into US in last 30 years.
Some dumped into the wild when they grow too big
or owners tire of them.
First noticed wild in Florida in 1979;
noticeable problem from 2000 forward. Estimate:
>100,000
Background to the python problem
Florida’s 46 native snakes are SMALL;
pythons are BIG.
common kingsnake
~1 m.
Coralsnake
~75 cmcottonmouth
~1 m
Background to the python problem
The species in the Everglades evolved with small snakes, not big ones.
Boid (constrictor) snakes went extinct in Florida
20.6-16.3 million years ago. . .
Pythons are active both night and day.
NET EFFECT:
Pythons eat:
a) many species >45 bird species, many mammals, reptiles
b) big species deer, rabbit, opossum, sheep, heron
c) a lot of prey big body = big food intake
d) predators alligator, bobcat, fox, coyote
http://www.washingtonpost.com/national/health-science/pythons-kill-off-native-animals-in-everglades/2012/01/30/gIQAdawJdQ_gallery.htmlhttp://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=Bz85xe7nhB5VAM&tbnid=RZI5Pn9tYWhjqM:&ved=0CAUQjRw&url=http://weblogs.sun-sentinel.com/news/politics/dcblog/pythons/&ei=fs03UcSDHaStygGYlYCgBg&bvm=bv.43287494,d.aWc&psig=AFQjCNEHFaVVhKJHJCISFuL8LpE1r-JE1Q&ust=1362697934999372http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=lVQpvf66LC9vfM&tbnid=Tq5xuw_t2xHq6M:&ved=0CAUQjRw&url=http://www.currion.net/2012/11/09/cottonmouth/&ei=P8w3UdbsBsPmygHww4C4Bw&bvm=bv.43287494,d.aWc&psig=AFQjCNE48pMKNGOOUrKilYSC-I_cUJoGNA&ust=1362697653509096http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=Ogwnu3h1y56vXM&tbnid=KOKnf7kwZN5TcM:&ved=0CAUQjRw&url=http://onlyhdwallpapers.com/high-definition-wallpaper/greyfox-high-resolution-desktop-hd-wallpaper-233715/&ei=Qsk3UffUDMWuqAGZh4CwBA&psig=AFQjCNEwLNX0gpLdUhhQ5F9ihMWwkLWjvQ&ust=1362696882832244http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=ZtLkxCoT-mpTbM&tbnid=vRwmDWlVdmeFIM:&ved=0CAUQjRw&url=http://www.friedchickenandcoffee.com/2010/01/06/strapped-redneck/woodstork/&ei=78g3UdnPCsz-rAHZvICoAg&psig=AFQjCNHxbMX5iQZ7yFWLnBJIfuGGSeab9Q&ust=1362696770495844http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=_Aju2k7iQNkd6M&tbnid=1QilznCmuF-5PM:&ved=0CAUQjRw&url=http://www.allaboutbirds.org/guide/Limpkin/&ei=pcg3Ua64JcvMqQHK14C4CQ&psig=AFQjCNEEQFoXZC1vD2hCLWuslQzPokhf4w&ust=1362696713685772http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=7kRxzqVJAJE7UM&tbnid=ChadQ63uo2WY3M:&ved=0CAUQjRw&url=http://www.favorfloridakeys.com/Croc%20Lake%20NWR.htm&ei=WMg3UfmdC86yqAHm8YDICQ&psig=AFQjCNGLaBEl4ie8NXh1v8wqZV4JCC5uiA&ust=1362696637822045
8/18/2019 Biol 201 Lecture 19 Communities_2
4/9
3/20/20
South Florida sampling locations in relation to python distribution.
Dorcas M E et al. PNAS 2012;109:2418-2422
©2012 by National Academy of Sciences
Python removals from Everglades and its environs from 1995 –2010.
Dorcas M E et al. PNAS 2012;109:2418-2422
©2012 by National Academy of Sciences
Mammal roadkills from 1993 –1999, before pythons become common.
Dorcas M E et al. PNAS 2012;109:2418-2422
©2012 by National Academy of Sciences
Mammal declines after python increases
Dorcas M E et al. PNAS 2012;109:2418-2422
©2012 by National Academy of Sciences
Before pythons
After pythons
Many pythons
A few pythons
No pythons
Mammal declines after python increases: 2003-2011
87.5% decline in bobcats
99.3% decline in raccoons98.9% decline in opossums
94.1% decline in deer
No observations in 2011
cottontails
red fox (also grey fox)
Other invaders in Florida
Invasive species in Florida
cost >$0.5 billion per year
Argentine Tegu (~3 ft long):
eats sea turtle eggs
Nile monitor lizard
(~6 ft long):
kills pets
Cuban tree frog (~5”):
eats native frog species
lionfish:
eats native fish
http://localhost/var/www/apps/conversion/tmp/scratch_4//upload.wikimedia.org/wikipedia/commons/b/bf/Pterois_volitans_Manado-e_edit.jpghttp://en.wikipedia.org/wiki/File:Tupinambis-merianae-BA-Zoo.JPGhttp://floridadventure2012.files.wordpress.com/2011/09/nile_monitor.jpghttp://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=N4m1hhxzESGOXM&tbnid=OtR9vXfk9AbFiM:&ved=0CAUQjRw&url=http://animals.nationalgeographic.com/animals/mammals/red-fox/&ei=wNQ3UeD4AYrdrQGvxoGoCQ&psig=AFQjCNHBxq8yX-XAYIdSxjvtqDHZxYaefg&ust=1362699825421513http://localhost/var/www/apps/conversion/tmp/scratch_4//upload.wikimedia.org/wikipedia/commons/8/84/Sylvilagus_floridanus_14070.JPGhttp://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=HaCFhgyV8VJk4M&tbnid=3WCR977R2pIp1M:&ved=0CAUQjRw&url=http://animals.nationalgeographic.com/animals/mammals/white-tailed-deer/&ei=MdM3UZTlI4rKqQGGrIC4CQ&psig=AFQjCNHqsda0-uGAVtX_47kO3G79CZ7T1Q&ust=1362699434636576http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=M66kCEKBdhiiPM&tbnid=ZsJ-Oyc7UZhvWM:&ved=0CAUQjRw&url=http://true-wildlife.blogspot.com/2010/11/bobcat.html&ei=6dI3UYSJG4vPqAGOwYDQBA&psig=AFQjCNEc9g0iTZnktmqTnuzwVv7J_2i5PQ&ust=1362699361505005http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=tzoBgssAQ6s_EM&tbnid=9J-ZTzB_wmuexM:&ved=0CAUQjRw&url=http://www2.needham.k12.ma.us/eliot/technology/lessons/animals/opossum.htm&ei=dtI3UZX6DMW0qAGq6IDwCw&psig=AFQjCNG6_R9qxcyw4UT9USKK713ot7XymQ&ust=1362699244155781
8/18/2019 Biol 201 Lecture 19 Communities_2
5/9
3/20/20
The human response 1: new law banning transport
of pythons across state lines
Jan 17, 2012, Federal ban on movement of 4 snake species
across state lines:
Burmese python
Anaconda
2 African pythons
• No new imports of these snakes as pets
• Cannot ship snakes across state lines
• Can’t even take your snake to the veterinarian across
state lines
The human response 2: the 2013 Python Challenge
Jan 12 – Feb 10, open hunt for pythons.
Cash rewards for most killed, largest killed.
1600 people from 38 states registered. . .
68 pythons killed
The human response 3: aftermath of the Python
Challenge
--No Python Challenge this year; need better trained
people to go after these animals
(volunteer Python Patrol?)
--All killed animals were necropsied. . .lots of
cotton rats as prey
The human response 3: aftermath of the Python
Challenge
A few weeks ago, the “Swamp Apes” were out
scouting for pythons again. . .and found a Nile Crocodile!
--Big & aggressive species
--Kill humans
--Kill big prey
Do some species have more impact
on their communities than others?Step 4 of being a community ecologist:
Figure out which species have large or small impactson presence / abundance of other species in the community.
python additions in Florida?
loss of wolves in most of US?
severe decline of Lyall’s mariposa lily
in S. Okanagan?
Keystone species: disproportionate impact
on community structure relative to their abundance
http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=kiL2PloTanxVcM&tbnid=kjfkW9JJtRwQOM:&ved=0CAUQjRw&url=http://www.nps.gov/wica/naturescience/bison-wallow.htm&ei=Gdo3UY37EcPPqQHJhICYBw&psig=AFQjCNHuS4zLr7bpY2ac7TBSb9bYTg16hw&ust=1362701204980182http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=7Ed0mVDmDu_H1M&tbnid=Slgf4kQdxXHV1M:&ved=0CAUQjRw&url=http://www.bite.ca/bitedaily/2012/07/animal-of-the-week-the-beaver/&ei=hdk3UfzvIsK9qgGUl4HIDg&psig=AFQjCNGoR99_HwDFtHVrem4VwIn5sM7E-g&ust=1362701053762603http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=3xsf83RBXBvpsM&tbnid=l2tU16D1xmKkKM:&ved=0CAUQjRw&url=http://www.floridasportsman.com/2013/01/14/fwc-kicks-off-2013-python-challenge/&ei=C9c3UenDKYjmrAHrzYHgCw&psig=AFQjCNHWt42tQlt_2JOQGQmy6tk7dyiUrQ&ust=1362700350606736http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=bx7pP7B_jX26IM&tbnid=ulaCsSHPI_w71M:&ved=0CAUQjRw&url=http://www.voxxi.com/python-challenge-draws-about-800-hunters/&ei=yNY3Uci9LMHhrAGj6YHQCw&psig=AFQjCNHWt42tQlt_2JOQGQmy6tk7dyiUrQ&ust=1362700350606736
8/18/2019 Biol 201 Lecture 19 Communities_2
6/9
3/20/20
Keystone species: creating habitat (ecosystem engineers) Keystone species: key trophic players
1871
1981
Succession: changes in communities through time
Succession - colonization and extinctions on a site by
species through time.
(Changes in richness, evenness, and dominance!)
Primary succession - succession following
disturbance that removes most biotic material from
the site.
Secondary succession - succession following a
disturbance that leaves soil, seeds, or organisms on
site.
Biological legacy - organisms, propagules, and
organic materials that survive disturbance.
Basic definitions of succession
How predictable (repeatable) is it?
after same kind of disturbance, will same
kind of community re-form by going through
same steps?
How idiosyncratic is it?
Will legacies, timing, and other site- and time-
specific details lead to different communities
after the same kind of disturbance?
Did disturbance fundamentally change the abiotic
conditions?
Key questions about succession Abiotic shift: boiling sulfuric acid kills trees
http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=BT5mdSYAlk3SBM&tbnid=Cuqox5vJ46TbQM:&ved=0CAUQjRw&url=http://canadafurandfeathers.blogspot.com/2012/04/prairie-birds-and-prairie-dogs.html&ei=-9o3UcCQK4vuqQHXkICYCw&psig=AFQjCNGRxEYX3kZ_ajv4TjDjAPBlLHZLVg&ust=1362701416014037http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=pE87M9yyqfXrOM&tbnid=qapT66QIYYQ-zM:&ved=0CAUQjRw&url=http://www.panthera.org/photo-of-day?page=6&ei=vdo3UcnOKIbpqAGuz4CQCA&psig=AFQjCNEAdSym-uNyFhqdI4XUZxoCgZkjmA&ust=1362701367724305http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=Y0P902Oo92kLUM&tbnid=tuaFwbJDr58v-M:&ved=0CAUQjRw&url=http://zoo4950.wordpress.com/2011/03/13/butting-heads-with-the-beaver/&ei=e9o3Ua2YFsSVrAGRvoD4DA&psig=AFQjCNE_zlgaX48gHwYlr8fjRyntSpAk0A&ust=1362701302662072http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=7Ed0mVDmDu_H1M&tbnid=Slgf4kQdxXHV1M:&ved=0CAUQjRw&url=http://www.bite.ca/bitedaily/2012/07/animal-of-the-week-the-beaver/&ei=hdk3UfzvIsK9qgGUl4HIDg&psig=AFQjCNGoR99_HwDFtHVrem4VwIn5sM7E-g&ust=1362701053762603
8/18/2019 Biol 201 Lecture 19 Communities_2
7/9
3/20/20
Tree kill without a huge abiotic shift: blow-down Glacial retreat—exposes mineral cobble
Primary succession: colonizing after glacial retreatPlant colonization in Glacier Bay, Alaska,
following glacial retreat
Secondary succession:
hardwood forest regeneration after fire
Key issues during PRIMARY succession
(predictable vs. idiosyncratic patterns)
1. Where do colonists come from?
2. What abiotic conditions do they find?
3. How do species’ interactions (facilitation, competition,
predation etc.) determine which species dominate?
4. What spatial patterns are evident in colonization?
http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=yihuH_ctj6_dtM&tbnid=N7odwdcshrV64M:&ved=0CAUQjRw&url=http://www.ethlife.ethz.ch/archive_articles/100607_Gletscher_su/index_EN&ei=h0k_UYfoI8izrQH-lIDQBQ&bvm=bv.43287494,d.aWM&psig=AFQjCNHmu308y5sIdO7-8yw02kQGX0weCw&ust=1363188472149111http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=t9E1DUb6MVH0dM&tbnid=yrSHXvSc67NTxM:&ved=0CAUQjRw&url=http://www.redwood.forestthreats.org/wind.htm&ei=1l4_UbzjLsW0qAHxi4HICg&bvm=bv.43287494,d.aWM&psig=AFQjCNFTdzMa6wY4S-8UtXpWgK7CQSpGGQ&ust=1363193926965563
8/18/2019 Biol 201 Lecture 19 Communities_2
8/9
3/20/20
Key issues during SECONDARY succession
(predictable vs. idiosyncratic patterns)
1. Where do colonists come from? will previous dominant
continue as dominant?
2. What abiotic conditions do they find?
3. How do species’ interactions (facilitation, competition,
predation etc.) determine which species dominate?
4. What legacies are present and how important are they?
5. Will the same ‘climax’ communities come back
after going through the same stages?
Fire and volcanoes: key influences in Yellowstone
volcanoes: temperature, soils
(andesite, rhyolite)
fire: soils, seeds, biomass
Mature forests in Yellowstone: fuel for fires Regrowth of Lodgepole pines in Yellowstone after fire
Key question
--What drives density of stands regrowing after fire?
Major approach
--map areas of different sapling densities &
relate to soil, fire history, elevation
Turner et al. 2004. Ecosystems 7:751-775.
Predictors of post-fire regeneration:
elevation, soil, serotiny, and fire severity
Regeneration spans 6 orders of magnitude
8/18/2019 Biol 201 Lecture 19 Communities_2
9/9
3/20/20
Colonists (and dominance/
evenness) affected by timing—
--of disturbance, and
--of species dispersal
“Succession” occurs at very different time scales
(remember, it’s just community shifts through time. . .)
http://www.google.ca/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=HB59MBKy70Wd2M&tbnid=8GhEmSljtlwqzM:&ved=0CAUQjRw&url=http://www.cosmographicresearch.org/prelim_glacial_maximum.htm&ei=X1M_Ue77C8HhrAHeh4CACg&bvm=bv.43287494,d.aWM&psig=AFQjCNHS1LZ_cqLY6M9YnXfmtkykW29kDw&ust=1363191003406523