TY  - JOUR
A1  - Houlahan, Jeff E.
A1  - Currie, David J.
A1  - Cottenie, Karl
A1  - Cumming, Graeme S.
A1  - Ernest, S. K. Morgan
A1  - Findlay, C. Scott
A1  - Fuhlendorf, Samuel D.
A1  - Gaedke, Ursula
A1  - Legendre, Pierre
A1  - Magnuson, John J.
A1  - McArdle, Brian H.
A1  - Muldavin, Esteban H.
A1  - Noble, David
A1  - Russell, Robert
A1  - Stevens, Richard D.
A1  - Willis, Trevor J.
A1  - Woiwod, Ian P.
A1  - Wondzell, Steve M.
T1  - Compensatory dynamics are rare in natural ecological communities
N2  - In population ecology, there has been a fundamental controversy about the relative importance of competition- driven (density-dependent) population regulation vs. abiotic influences such as temperature and precipitation. The same issue arises at the community level; are population sizes driven primarily by changes in the abundances of cooccurring competitors (i.e., compensatory dynamics), or do most species have a common response to environmental factors? Competitive interactions have had a central place in ecological theory, dating back to Gleason, Volterra, Hutchison and MacArthur, and, more recently, Hubbell's influential unified neutral theory of biodiversity and biogeography. If competitive interactions are important in driving year-to-year fluctuations in abundance, then changes in the abundance of one species should generally be accompanied by compensatory changes in the abundances of others. Thus, one necessary consequence of strong compensatory forces is that, on average, species within communities will covary negatively. Here we use measures of community covariance to assess the prevalence of negative covariance in 41 natural communities comprising different taxa at a range of spatial scales. We found that species in natural communities tended to covary positively rather than negatively, the opposite of what would be expected if compensatory dynamics were important. These findings suggest that abiotic factors such as temperature and precipitation are more important than competitive interactions in driving year-to-year fluctuations in species abundance within communities.
Y1  - 2007
UR  - http://www.pnas.org/
U6  - https://doi.org/10.1073/pnas.0603798104
SN  - 0027-8424
ER  - 
TY  - GEN
A1  - Hodgkins, Suzanne B.
A1  - Richardson, Curtis J.
A1  - Dommain, René
A1  - Wang, Hongjun
A1  - Glaser, Paul H.
A1  - Verbeke, Brittany
A1  - Winkler, B. Rose
A1  - Cobb, Alexander R.
A1  - Rich, Virginia I.
A1  - Missilmani, Malak
A1  - Flanagan, Neal
A1  - Ho, Mengchi
A1  - Hoyt, Alison M.
A1  - Harvey, Charles F.
A1  - Vining, S. Rose
A1  - Hough, Moira A.
A1  - Moore, Tim R.
A1  - Richard, Pierre J. H.
A1  - De La Cruz, Florentino B.
A1  - Toufaily, Joumana
A1  - Hamdan, Rasha
A1  - Cooper, William T.
A1  - Chanton, Jeffrey P.
T1  - Tropical peatland carbon storage linked to global latitudinal trends in peat recalcitrance
T2  - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
N2  - Peatlands represent large terrestrial carbon banks. Given that most peat accumulates in boreal regions, where low temperatures and water saturation preserve organic matter, the existence of peat in (sub)tropical regions remains enigmatic. Here we examined peat and plant chemistry across a latitudinal transect from the Arctic to the tropics. Near-surface low-latitude peat has lower carbohydrate and greater aromatic content than near-surface high-latitude peat, creating a reduced oxidation state and resulting recalcitrance. This recalcitrance allows peat to persist in the (sub)tropics despite warm temperatures. Because we observed similar declines in carbohydrate content with depth in high-latitude peat, our data explain recent field-scale deep peat warming experiments in which catotelm (deeper) peat remained stable despite temperature increases up to 9 degrees C. We suggest that high-latitude deep peat reservoirs may be stabilized in the face of climate change by their ultimately lower carbohydrate and higher aromatic composition, similar to tropical peats.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1125 
KW  - dissolved organic matter
KW  - greenhouse gas fluxes
KW  - permafrost thaw
KW  - Northern Minnesota
KW  - FTIR spectroscopy
KW  - lignin content
KW  - brown rot
KW  - decomposition
KW  - chemistry
KW  - dynamics
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-459658
SN  - 1866-8372
IS  - 1125
ER  - 
TY  - JOUR
A1  - Hodgkins, Suzanne B.
A1  - Richardson, Curtis J.
A1  - Dommain, Rene
A1  - Wang, Hongjun
A1  - Glaser, Paul H.
A1  - Verbeke, Brittany
A1  - Winkler, B. Rose
A1  - Cobb, Alexander R.
A1  - Rich, Virginia I.
A1  - Missilmani, Malak
A1  - Flanagan, Neal
A1  - Ho, Mengchi
A1  - Hoyt, Alison M.
A1  - Harvey, Charles F.
A1  - Vining, S. Rose
A1  - Hough, Moira A.
A1  - Moore, Tim R.
A1  - Richard, Pierre J. H.
A1  - De la Cruz, Florentino B.
A1  - Toufaily, Joumana
A1  - Hamdan, Rasha
A1  - Cooper, William T.
A1  - Chanton, Jeffrey P.
T1  - Tropical peatland carbon storage linked to global latitudinal trends in peat recalcitrance
JF  - Nature Communications
N2  - Peatlands represent large terrestrial carbon banks. Given that most peat accumulates in boreal regions, where low temperatures and water saturation preserve organic matter, the existence of peat in (sub)tropical regions remains enigmatic. Here we examined peat and plant chemistry across a latitudinal transect from the Arctic to the tropics. Near-surface low-latitude peat has lower carbohydrate and greater aromatic content than near-surface high-latitude peat, creating a reduced oxidation state and resulting recalcitrance. This recalcitrance allows peat to persist in the (sub)tropics despite warm temperatures. Because we observed similar declines in carbohydrate content with depth in high-latitude peat, our data explain recent field-scale deep peat warming experiments in which catotelm (deeper) peat remained stable despite temperature increases up to 9 degrees C. We suggest that high-latitude deep peat reservoirs may be stabilized in the face of climate change by their ultimately lower carbohydrate and higher aromatic composition, similar to tropical peats.
Y1  - 2018
U6  - https://doi.org/10.1038/s41467-018-06050-2
SN  - 2041-1723
VL  - 9
PB  - Nature Publ. Group
CY  - London
ER  -