Stephen T Jackson, Ph.D. (Former Employee)
Science and Products
Filter Total Items: 48
Space can substitute for time in predicting climate-change effects on biodiversity Space can substitute for time in predicting climate-change effects on biodiversity
“Space-for-time” substitution is widely used in biodiversity modeling to infer past or future trajectories of ecological systems from contemporary spatial patterns. However, the foundational assumption—that drivers of spatial gradients of species composition also drive temporal changes in diversity—rarely is tested. Here, we empirically test the space-for-time assumption by constructing...
Authors
Jessica L. Blois, John W. Williams, Matthew C. Fitzpatrick, Stephen T. Jackson, Simon Ferrier
Ecology and the ratchet of events: climate variability, niche dimensions, and species distributions Ecology and the ratchet of events: climate variability, niche dimensions, and species distributions
Climate change in the coming centuries will be characterized by interannual, decadal, and multidecadal fluctuations superimposed on anthropogenic trends. Predicting ecological and biogeographic responses to these changes constitutes an immense challenge for ecologists. Perspectives from climatic and ecological history indicate that responses will be laden with contingencies, resulting...
Authors
Stephen T. Jackson, Julio L. Betancourt, Robert K. Booth, Stephen T. Gray
Role of multidecadal climate variability in a range extension of pinyon pine Role of multidecadal climate variability in a range extension of pinyon pine
Evidence from woodrat middens and tree rings at Dutch John Mountain (DJM) in northeastern Utah reveal spatiotemporal patterns of pinyon pine (Pinus edulis Engelm.) colonization and expansion in the past millennium. The DJM population, a northern outpost of pinyon, was established by long-distance dispersal (~40 km). Growth of this isolate was markedly episodic and tracked multidecadal...
Authors
Stephen T. Gray, Julio L. Betancourt, Stephen T. Jackson, Robert G. Eddy
Classification tree and minimum-volume ellipsoid analyses of the distribution of ponderosa pine in the western USA Classification tree and minimum-volume ellipsoid analyses of the distribution of ponderosa pine in the western USA
Aim? Ponderosa pine (Pinus ponderosa Douglas ex Lawson & C. Lawson) is an economically and ecologically important conifer that has a wide geographic range in the western USA, but is mostly absent from the geographic centre of its distribution - the Great Basin and adjoining mountain ranges. Much of its modern range was achieved by migration of geographically distinct Sierra Nevada (P...
Authors
Jodi R. Norris, Stephen T. Jackson, Julio L. Betancourt
A 40,000-year woodrat-midden record of vegetational and biogeographical dynamics in north-eastern Utah A 40,000-year woodrat-midden record of vegetational and biogeographical dynamics in north-eastern Utah
Aim A conspicuous climatic and biogeographical transition occurs at 40-45° N in western North America. This pivot point marks a north–south opposition of wet and dry conditions at interannual and decadal time-scales, as well as the northern and southern limits of many dominant western plant species. Palaeoecologists have yet to focus on past climatic and biotic shifts along this...
Authors
Stephen T. Jackson, Julio L. Betancourt, Mark E. Lyford, Stephen T. Gray, Kate Aasen Rylander
Differentiating climatic and successional influences on long-term development of a marsh Differentiating climatic and successional influences on long-term development of a marsh
Comparison of long—term records of local wetland vegetation dynamics with regional, climate—forced terrestrial vegetation changes can be used to differentiate the rates and effects of autogenic successional processes and allogenic environmental change on wetland vegetation dynamics. We studied Holocene plant macrofossil and pollen sequences from Portage Marsh, a shallow, 18—ha marsh in
Authors
Darren K. Singer, Stephen T. Jackson, Barbara J. Madsen, Douglas A. Wilcox
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Filter Total Items: 48
Space can substitute for time in predicting climate-change effects on biodiversity Space can substitute for time in predicting climate-change effects on biodiversity
“Space-for-time” substitution is widely used in biodiversity modeling to infer past or future trajectories of ecological systems from contemporary spatial patterns. However, the foundational assumption—that drivers of spatial gradients of species composition also drive temporal changes in diversity—rarely is tested. Here, we empirically test the space-for-time assumption by constructing...
Authors
Jessica L. Blois, John W. Williams, Matthew C. Fitzpatrick, Stephen T. Jackson, Simon Ferrier
Ecology and the ratchet of events: climate variability, niche dimensions, and species distributions Ecology and the ratchet of events: climate variability, niche dimensions, and species distributions
Climate change in the coming centuries will be characterized by interannual, decadal, and multidecadal fluctuations superimposed on anthropogenic trends. Predicting ecological and biogeographic responses to these changes constitutes an immense challenge for ecologists. Perspectives from climatic and ecological history indicate that responses will be laden with contingencies, resulting...
Authors
Stephen T. Jackson, Julio L. Betancourt, Robert K. Booth, Stephen T. Gray
Role of multidecadal climate variability in a range extension of pinyon pine Role of multidecadal climate variability in a range extension of pinyon pine
Evidence from woodrat middens and tree rings at Dutch John Mountain (DJM) in northeastern Utah reveal spatiotemporal patterns of pinyon pine (Pinus edulis Engelm.) colonization and expansion in the past millennium. The DJM population, a northern outpost of pinyon, was established by long-distance dispersal (~40 km). Growth of this isolate was markedly episodic and tracked multidecadal...
Authors
Stephen T. Gray, Julio L. Betancourt, Stephen T. Jackson, Robert G. Eddy
Classification tree and minimum-volume ellipsoid analyses of the distribution of ponderosa pine in the western USA Classification tree and minimum-volume ellipsoid analyses of the distribution of ponderosa pine in the western USA
Aim? Ponderosa pine (Pinus ponderosa Douglas ex Lawson & C. Lawson) is an economically and ecologically important conifer that has a wide geographic range in the western USA, but is mostly absent from the geographic centre of its distribution - the Great Basin and adjoining mountain ranges. Much of its modern range was achieved by migration of geographically distinct Sierra Nevada (P...
Authors
Jodi R. Norris, Stephen T. Jackson, Julio L. Betancourt
A 40,000-year woodrat-midden record of vegetational and biogeographical dynamics in north-eastern Utah A 40,000-year woodrat-midden record of vegetational and biogeographical dynamics in north-eastern Utah
Aim A conspicuous climatic and biogeographical transition occurs at 40-45° N in western North America. This pivot point marks a north–south opposition of wet and dry conditions at interannual and decadal time-scales, as well as the northern and southern limits of many dominant western plant species. Palaeoecologists have yet to focus on past climatic and biotic shifts along this...
Authors
Stephen T. Jackson, Julio L. Betancourt, Mark E. Lyford, Stephen T. Gray, Kate Aasen Rylander
Differentiating climatic and successional influences on long-term development of a marsh Differentiating climatic and successional influences on long-term development of a marsh
Comparison of long—term records of local wetland vegetation dynamics with regional, climate—forced terrestrial vegetation changes can be used to differentiate the rates and effects of autogenic successional processes and allogenic environmental change on wetland vegetation dynamics. We studied Holocene plant macrofossil and pollen sequences from Portage Marsh, a shallow, 18—ha marsh in
Authors
Darren K. Singer, Stephen T. Jackson, Barbara J. Madsen, Douglas A. Wilcox
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.