Northern Peatlands: Role in the Carbon Cycle and Probable Responses to Climatic Warming Tập 1 Số 2 - Trang 182-195 - 1991
Eville Gorham
Boreal and subarctic peatlands comprise a carbon pool of 455 Pg that has
accumulated during the postglacial period at an average net rate of 0.096 Pg/yr
(1 Pg = 1015g). Using Clymo's (1984) model, the current rate is estimated at
0.076 Pg/yr. Longterm drainage of these peatlands is estimated to be causing the
oxidation to CO2 of a little more than 0.0085 Pg/yr, with conbustion of fuel
peat adding ... hiện toàn bộ
Sample selection bias and presence‐only distribution models: implications for background and pseudo‐absence data Tập 19 Số 1 - Trang 181-197 - 2009
Steven J. Phillips, Miroslav Dudík, Jane Elith, Catherine H. Graham, Anthony Lehmann, John R. Leathwick, Simon Ferrier
Most methods for modeling species distributions from occurrence records require
additional data representing the range of environmental conditions in the
modeled region. These data, called background or pseudo‐absence data, are
usually drawn at random from the entire region, whereas occurrence collection is
often spatially biased toward easily accessed areas. Since the spatial bias
generally resul... hiện toàn bộ
Global assessment of nitrogen deposition effects on terrestrial plant diversity: a synthesis Tập 20 Số 1 - Trang 30-59 - 2010
Roland Bobbink, Kevin Hicks, James N. Galloway, Till Spranger, Rob Alkemade, M. R. Ashmore, Mercedes Bustamante, Steve Cinderby, Eric A. Davidson, Frank Dentener, Bridget A. Emmett, J. W. Erisman, Mark E. Fenn, Frank S. Gilliam, Annika Nordin, Linda H. Pardo, W. de Vries
Atmospheric nitrogen (N) deposition is a recognized threat to plant diversity in
temperate and northern parts of Europe and North America. This paper assesses
evidence from field experiments for N deposition effects and thresholds for
terrestrial plant diversity protection across a latitudinal range of main
categories of ecosystems, from arctic and boreal systems to tropical forests.
Current think... hiện toàn bộ
CLIMATE CHANGE AND FORESTS OF THE FUTURE: MANAGING IN THE FACE OF UNCERTAINTY Tập 17 Số 8 - Trang 2145-2151 - 2007
Constance I. Millar, Nathan L. Stephenson, Scott L. Stephens
We offer a conceptual framework for managing forested ecosystems under an
assumption that future environments will be different from present but that we
cannot be certain about the specifics of change. We encourage flexible
approaches that promote reversible and incremental steps, and that favor ongoing
learning and capacity to modify direction as situations change. We suggest that
no single solut... hiện toàn bộ
The Report of the Ecological Society of America Committee on the Scientific Basis for Ecosystem Management Tập 6 Số 3 - Trang 665-691 - 1996
Norman L. Christensen, Ann M. Bartuska, James H. Brown, Stephen M Carpenter, Carla M. D’Antonio, Rober Francis, Jerry F. Franklin, James A. MacMahon, Reed F. Noss, David Parsons, Charles H. Peterson, Monica G. Turner, Robert G. Woodmansee
Ecosystem management is management driven by explicit goals, executed by
policies, protocols, and practices, and made adaptable by monitoring and
research based on our best understanding of the ecological interactions and
processes necessary to sustain ecosystem composition, structure, and function.
In recent years, sustainability has become an explicitly stated, even
legislatively mandated, goal ... hiện toàn bộ
Land Use and Avian Species Diversity Along an Urban Gradient Tập 6 Số 2 - Trang 506-519 - 1996
Robert B. Blair
I examined the distribution and abundance of bird species across an urban
gradient, and concomitant changes in community structure, by censuring summer
resident bird populations at six sites in Santa Clara County, California (all
former oak woodlands). These sites represented a gradient of urban land use that
ranged from relatively undisturbed to highly developed, and included a
biological preserv... hiện toàn bộ