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Registros recuperados: 63 | |
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Cavender-Bares, Jeannine; Department of Ecology, Evolution and Behavior, University of Minnesota; Institute on Environment, University of Minnesota; cavender@umn.edu; Polasky, Stephen; Department of Applied Economics, University of Minnesota; Department of Ecology, Evolution and Behavior, University of Minnesota; Institute on Environment, University of Minnesota; polasky@umn.edu; King, Elizabeth; Biological Sciences, Odum School of Ecology, University of Georgia; Warnell School of Forestry and Natural Resources, University of Georgia; egking@uga.edu. |
Achieving sustainability, i.e., meeting the needs of current populations without compromising the needs of future generations, is the major challenge facing global society in the 21st century. Navigating the inherent trade-offs between provisioning, regulating, cultural, and supporting ecosystem services, and doing so in a way that does not compromise natural capital needed to provide services in the future, is critical for sustainable resource management. Here we build upon existing literature, primarily from economics and ecology, to present an analytical framework that integrates (1) the ecological mechanisms that underpin ecosystem services, (2) biophysical trade-offs and inherent limits that constrain management options, (3) preferences and values... |
Tipo: Peer-Reviewed Insight |
Palavras-chave: Dynamics; Ecosystem services; Efficiency frontier; Management constraints; Preferences; Stakeholders; Time lags; Trade-offs. |
Ano: 2015 |
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Walker, Brian; CSIRO Sustainable Ecosystems; Brian.Walker@csiro.au; Steffen, Will; ; Will.Steffen@dwe.csiro.au. |
Global change is the net effect of individual and interactive effects of changes in land use, atmospheric composition, biological diversity, and climate. A synthesis of the past six years' activities of the Global Change and Terrestrial Ecosystems project of the IGBP (International Geosphere-Biosphere Programme) deals with global change effects as ecosystem responses and living with global change. Ecosystem responses are considered in terms of changes in function and vegetation composition/structure. Field experiments of elevated CO2 effects on aboveground biomass show, on average, a positive effect on biomass, ranging from -20% to +80%. Some early predictions of CO2 effects (C3 vs. C4 plants, N-fixers, C:N in litter) are not generally supported, and it... |
Tipo: Peer-Reviewed Reports |
Palavras-chave: Agriculture; Biomes; Carbon dioxide; Climate; Dynamics; Ecosystem functioning; Global change; Impacts; Land use; Terrestrial biosphere; Vegetation changes.. |
Ano: 1997 |
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Guillon, Erwan; Menot, Lenaick; Decker, Carole; Krylova, Elena; Olu, Karine. |
The high biodiversity found at cold seeps, despite elevated concentrations of methane and hydrogen sulfide, is attributed to multiple sources of habitat heterogeneity. In addition to geological and geochemical processes, biogenic habitats formed by large symbiont-bearing taxa, such as bivalves and siboglinid tubeworms, or by microbial mats drive the biodiversity of small-sized fauna. However, because these habitat-forming species also depend on geochemical gradients, the respective influence of abiotic and biotic factors in structuring associated macrofaunal communities is often unresolved. The giant pockmark Regab located at 3200 m depth on the Congo margin is characterized by different fluid-flow regimes, providing a mosaic of the most common biogenic... |
Tipo: Text |
Palavras-chave: Cold-seep; Macrofauna; Diversity; Dynamics; Vesicomyid clams; Gulf of Guinea. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00361/47210/47165.pdf |
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Gerin, R.; Poulain, P. -m.; Taupier-letage, Isabelle; Millot, C.; Ben Ismail, S.; Sammari, Cherif. |
Within the framework of the EGITTO/EGYPT programs, the spatial structure and the temporal variability of the surface circulation in the eastern basin of the Mediterranean Sea was studied with satellite-tracked drifters. A total of 97 drifters drogued to 15-m nominal depth were released between September 2005 and March 2007, regularly along ship-of-opportunity routes in the Sicily Channel and within specific structures during dedicated campaigns in the Levantine sub-basin. This study complements previous ones in the former and in the Ionian, but it is the first one in the latter. After editing and low-pass filtering, the drifter trajectories were used to estimate pseudo-Eulerian statistics: mean current, variance ellipses, mean and eddy kinetic energies. A... |
Tipo: Text |
Palavras-chave: Lagrangian drifters; General circulation; Undrogued drifters; Sea; Variability; Features; Basin; Model; Dynamics. |
Ano: 2009 |
URL: https://archimer.ifremer.fr/doc/00204/31480/29891.pdf |
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Broche, P; Devenon, Jean-luc; Forget, P; De Maistre, Jc; Naudin, Jj; Cauwet, G. |
The complicated dynamic processes occurring when fluvial waters mix with marine waters control the nature and the fluxes of materials exported tay rivers to the sea. Understanding these processes is of primary importance in evaluating budgets. In wide-open estuarine situations these processes take place under the influence of an intense turbulence induced by tides. Conversely, the Rhone waters spread into the Mediterranean Sea in the form of an easily distinguishable buoyant plume often extending far offshore from the mouth of the river. The aim of this study is to describe the dynamic and hydrological fields on the basis of eulerian VHF radar mapping of surface currents coupled with lagrangian in situ physical or geochemical measurements. This paper... |
Tipo: Text |
Palavras-chave: Panache fluvial; Radar VHF; Rhône; Dynamique; River plume; VHF radar; Rhone; Dynamics. |
Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/00325/43636/43229.pdf |
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Vialard, Jerome; Shenoi, S. S. C.; Mccreary, J. P.; Shankar, D.; Durand, F.; Fernando, V.; Shetye, S. R.. |
A new observational record of upper-ocean currents at 15 degrees N on the western coast of India is dominated by intraseasonal (55 - 110 day) variations of alongshore currents, whereas sea level at the same location has a clear seasonal signal. These observations can be interpreted within the framework of linear wave theory. At 15 degrees N, the minimum period for planetary waves is similar to 90 day, meaning that intraseasonal energy is largely trapped at the coast in the form of poleward-propagating Kelvin waves, while lower-frequency signals associated with the annual cycle can radiate offshore as planetary waves. This dynamical difference results in a steeper offshore slope of sea level at intraseasonal timescale, and thus stronger geostrophic... |
Tipo: Text |
Palavras-chave: Variability; Dynamics; Circulation; Currents. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/00185/29631/27993.pdf |
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Ollitrault, Michel; Colin De Verdiere, Alain. |
The mean ocean circulation near 1000-m depth is estimated with 100-km resolution from the Argo float displacements collected before 1 January 2010. After a thorough validation, the 400 000 or so displacements found in the 950–1150 dbar layer and with parking times between 4 and 17 days allow the currents to be mapped at intermediate depths with unprecedented details. The Antarctic Circumpolar Current (ACC) is the most prominent feature, but western boundary currents (and their recirculations) and alternating zonal jets in the tropical Atlantic and Pacific are also well defined. Eddy kinetic energy (EKE) gives the mesoscale variability (on the order of 10 cm2 s−2 in the interior), which is compared to the surface geostrophic altimetric EKE showing e-folding... |
Tipo: Text |
Palavras-chave: Circulation; Dynamics; Currents; Dynamics; Large-scale motions; Ocean circulation. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00174/28512/26877.pdf |
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Leckler, Fabien; Ardhuin, Fabrice; Peureux, Charles; Benetazzo, Alvise; Bergamasco, Filippo; Dulov, Vladimir. |
The energy level and its directional distribution are key observations for understanding the energy balance in the wind-wave spectrum between wind-wave generation, nonlinear interactions, and dissipation. Here, properties of gravity waves are investigated from a fixed platform in the Black Sea, equipped with a stereo video system that resolves waves with frequency f up to 1.4 Hz and wavelengths from 0.6 to 11 m. One representative record is analyzed, corresponding to young wind waves with a peak frequency fp = 0.33 Hz and a wind speed of 13 m s−1. These measurements allow for a separation of the linear waves from the bound second-order harmonics. These harmonics are negligible for frequencies f up to 3 times fp but account for most of the energy at higher... |
Tipo: Text |
Palavras-chave: Circulation; Dynamics; Waves; Oceanic; Observational techniques and algorithms; Remote sensing. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00284/39524/38017.pdf |
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Registros recuperados: 63 | |
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