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Wolfgang H Berger

Bio: Wolfgang H Berger is an academic researcher from Scripps Institution of Oceanography. The author has contributed to research in topics: Foraminifera & Glacial period. The author has an hindex of 72, co-authored 234 publications receiving 21719 citations. Previous affiliations of Wolfgang H Berger include University of California & University of California, Los Angeles.


Papers
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Journal Article•DOI•
27 Jul 2001-Science
TL;DR: Paleoecological, archaeological, and historical data show that time lags of decades to centuries occurred between the onset of overfishing and consequent changes in ecological communities, because unfished species of similar trophic level assumed the ecological roles of over-fished species until they too were overfished or died of epidemic diseases related to overcrowding as mentioned in this paper.
Abstract: Ecological extinction caused by overfishing precedes all other pervasive human disturbance to coastal ecosystems, including pollution, degradation of water quality, and anthropogenic climate change. Historical abundances of large consumer species were fantastically large in comparison with recent observations. Paleoecological, archaeological, and historical data show that time lags of decades to centuries occurred between the onset of overfishing and consequent changes in ecological communities, because unfished species of similar trophic level assumed the ecological roles of overfished species until they too were overfished or died of epidemic diseases related to overcrowding. Retrospective data not only help to clarify underlying causes and rates of ecological change, but they also demonstrate achievable goals for restoration and management of coastal ecosystems that could not even be contemplated based on the limited perspective of recent observations alone.

5,411 citations

Journal Article•DOI•
12 Jun 1970-Science
TL;DR: The diversity of a planktonic foraminiferal assemblage on the ocean floor depends on the state of preservation of that assemblages, and as dissolution progresses, species diversity decreases, but compound diversity first increases and then decreases; species dominance first decreases and then increases.
Abstract: The diversity of a planktonic foraminiferal assemblage on the ocean floor depends on the state of preservation of that assemblage. As dissolution progresses, species diversity (number of species in the assemblage) decreases, but compound diversity (based on relative species abundance) first increases and then decreases; species dominance first decreases and then increases. The reason for these changes is that the species most susceptible to solution deliver moresediment to the ocean floor than do species with solution-resistant shells, possibly because the more soluble tests are produced in surface waters, where growth and production are greatest.

875 citations

Book•
01 Jan 1996
TL;DR: In this paper, the authors present a model of the South Atlantic Ocean's circulation and its variability based on the TOPEX/POSEIDON mission data collected by the International Oceanographic and Atmospheric Organization (OIE).
Abstract: Central Themes of South Atlantic Circulation.- On the Circulation of the South Atlantic Ocean.- Transient-Tracer Information on Ventilation and Transport of South Atlantic Waters.- The Circulation and its Variability of the South Atlantic Ocean: First Results from the TOPEX/POSEIDON Mission.- The Zonal WOCE Sections in the South Atlantic.- South Atlantic Heat Transport at 11 S.- Comment on the South Atlantic's Role in the Global Circulation 121 -.- The Exchange of Water between the South Indian and South Atlantic Oceans.- The Benguela: Large Scale Features and Processes and System Variability.- The Southern Boundary of the South Atlantic.- Antarctic Intermediate Water in the South Atlantic.- Lagrangian Measurements in the Malvinas Current.- Circulation in the Deep Brazil Basin.- The Deep Water Regime in the Equatorial.- Chlorofluoromethanes in the Deep Equatorial Atlantic Revisited.- Modelling the Ocean Circulation in the South Atlantic: A Strategy for Dealing with Open Boundaries.- Mass and Heat Transports in the South Atlantic Derived from Historical Hydrographic Data.- Long-term Observation of Particle Fluxes in the Eastern Atlantic: Seasonality, Changes of Flux with Depth and Comparison with the Sediment Record.- Silica Signals in the South Atlantic.- On the Bathymetry of the Hunter Channel.- Expeditions into the Past: Paleoceanographic Studies in the South Atlantic.- Inverse Modelling of the Glacial Atlantic CirculationSystem: Investigation of Data Requirements.- Chemical Hydrography of the South Atlantic During the Last Glacial Maximum: Cd vs. ?13C.- High Latitude Deep Water Sources During the Last Glacial Maximum and the Intensity of the Global Oceanic Circulation.- Late Quaternary Surface Circulation in the South Atlantic: The Stable Isotope Record and implications for Heat Transport and Productivity.- Climate Feedback and Pleistocene Variations in the Atlantic South Equatorial Current.- Late Quaternary Surface Temperatures and Productivity in the East-Equatorial South Atlantic: Response to Changes in Trade/Monsoon Wind Forcing and Surface Water Advection.- Late Quaternary Movements of the Angola- Benguela Front, SE Atlantic, and Implications for Advection in the Equatorial Ocean.- Late Quaternary Deep Circulation in the Western Equatorial Atlantic.- Late Quaternary Deep Water Circulation in the South Atlantic: Reconstruction from Carbonate Dissolution and Benthic Stable Isotopes.- Clay Mineral Fluctuations in Late Quaternary Sediments of the Southeastern South Atlantic: Implications for Past Changes of Deep Water Advection.

568 citations

Journal Article•DOI•
TL;DR: Isotope paleontology uses the isotopic composition of fossil remains of organisms to make inferences about the physical surroundings of growth of the organisms (especially temperature), and to obtain clues about life history and modes of growth.

545 citations


Cited by
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Book•
30 Sep 1988
TL;DR: In this paper, the authors define definitions of diversity and apply them to the problem of measuring species diversity, choosing an index and interpreting diversity measures, and applying them to structural and structural diversity.
Abstract: Definitions of diversity. Measuring species diversity. Choosing an index and interpreting diversity measures. Sampling problems. Structural diversity. Applications of diversity measures. Summary.

10,957 citations

Journal Article•DOI•
27 Apr 2001-Science
TL;DR: This work focuses primarily on the periodic and anomalous components of variability over the early portion of this era, as constrained by the latest generation of deep-sea isotope records.
Abstract: Since 65 million years ago (Ma), Earth's climate has undergone a significant and complex evolution, the finer details of which are now coming to light through investigations of deep-sea sediment cores. This evolution includes gradual trends of warming and cooling driven by tectonic processes on time scales of 10(5) to 10(7) years, rhythmic or periodic cycles driven by orbital processes with 10(4)- to 10(6)-year cyclicity, and rare rapid aberrant shifts and extreme climate transients with durations of 10(3) to 10(5) years. Here, recent progress in defining the evolution of global climate over the Cenozoic Era is reviewed. We focus primarily on the periodic and anomalous components of variability over the early portion of this era, as constrained by the latest generation of deep-sea isotope records. We also consider how this improved perspective has led to the recognition of previously unforeseen mechanisms for altering climate.

8,903 citations

Journal Article•DOI•
27 Jul 2001-Science
TL;DR: Paleoecological, archaeological, and historical data show that time lags of decades to centuries occurred between the onset of overfishing and consequent changes in ecological communities, because unfished species of similar trophic level assumed the ecological roles of over-fished species until they too were overfished or died of epidemic diseases related to overcrowding as mentioned in this paper.
Abstract: Ecological extinction caused by overfishing precedes all other pervasive human disturbance to coastal ecosystems, including pollution, degradation of water quality, and anthropogenic climate change. Historical abundances of large consumer species were fantastically large in comparison with recent observations. Paleoecological, archaeological, and historical data show that time lags of decades to centuries occurred between the onset of overfishing and consequent changes in ecological communities, because unfished species of similar trophic level assumed the ecological roles of overfished species until they too were overfished or died of epidemic diseases related to overcrowding. Retrospective data not only help to clarify underlying causes and rates of ecological change, but they also demonstrate achievable goals for restoration and management of coastal ecosystems that could not even be contemplated based on the limited perspective of recent observations alone.

5,411 citations

Book Chapter•DOI•
01 Apr 1994-Oikos
TL;DR: The role that many organisms play in the creation, modification and maintenance of habitats does not involve direct trophic interactions between species, but they are nevertheless important and common.
Abstract: Interactions between organisms are a major determinant of the distribution and abundance of species. Ecology textbooks (e.g., Ricklefs 1984, Krebs 1985, Begon et al. 1990) summarise these important interactions as intra- and interspecific competition for abiotic and biotic resources, predation, parasitism and mutualism. Conspicuously lacking from the list of key processes in most text books is the role that many organisms play in the creation, modification and maintenance of habitats. These activities do not involve direct trophic interactions between species, but they are nevertheless important and common. The ecological literature is rich in examples of habitat modification by organisms, some of which have been extensively studied (e.g. Thayer 1979, Naiman et al. 1988).

5,407 citations

Journal Article•DOI•
15 Feb 2008-Science
TL;DR: This article developed an ecosystem-specific, multiscale spatial model to synthesize 17 global data sets of anthropogenic drivers of ecological change for 20 marine ecosystems and found that no area is unaffected by human influence and that a large fraction (41%) is strongly affected by multiple drivers.
Abstract: The management and conservation of the world's oceans require synthesis of spatial data on the distribution and intensity of human activities and the overlap of their impacts on marine ecosystems. We developed an ecosystem-specific, multiscale spatial model to synthesize 17 global data sets of anthropogenic drivers of ecological change for 20 marine ecosystems. Our analysis indicates that no area is unaffected by human influence and that a large fraction (41%) is strongly affected by multiple drivers. However, large areas of relatively little human impact remain, particularly near the poles. The analytical process and resulting maps provide flexible tools for regional and global efforts to allocate conservation resources; to implement ecosystem-based management; and to inform marine spatial planning, education, and basic research.

5,365 citations