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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 (approximately 40 km). Growth of this isolate was markedly episodic and tracked multidecadal variability in precipitation. Initial colonization occurred by AD 1246, but expansion was forestalled by catastrophic drought (1250-1288), which we speculate produced extensive mortality of Utah Juniper (Juniperus osteosperma (Torr.) Little), the dominant tree at DJM for the previous approximately 8700 years. Pinyon then...
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The 2008 - Present Ecosystem History of South Florida's Estuaries Database contains listings of all sites (modern and core) and modern monitoring site survey information (water chemistry, floral and faunal data, etc.). Three general types of data are contained within this database: 1) Modern Field Data (2008-present), 2) Master list of location information on all modern sites, and 3) Core data - location information. Data are available for modern sites (from 2008 to present) and cores in the general areas of Florida Bay, Biscayne Bay, and the southwest (Florida) coastal mangrove estuaries. Specific sites in the Florida Bay area include Taylor Creek, Bob Allen Key, Russell Bank, Pass Key, Whipray Basin, Rankin Bight,...
Categories: Data Release - Revised; Tags: 002, 004, 007, 008, 012, All tags...
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The mid-Piacenzian is known as a period of relative warmth when compared to the present day. A comprehensive understanding of conditions during the Piacenzian serves as both a conceptual model and a source for boundary conditions as well as means of verification of global climate model experiments. These data are provided as digital representations of mid Pliocene boundary conditions stored in NetCDF format for use with climate models.
The Colorado Plateau is a distinct physiographic province in western North America, which presently straddles the transition between summer-wet and summer-dry climatic regimes to the south and northwest, respectively. In addition to climate, the diversity of environments and plant communities on the Colorado Plateau has resulted from extreme topographic diversity. Desert lowlands as low as 360 m elevation are surrounded by forested plateaus, and even higher peaks greater than 3800 m elevation. This environmental diversity provides a unique opportunity to study the history of biotic communities in an arid region of North America. Although the Colorado Plateau harbours numerous potential sites, the paleoecological...
Pollen ratios and linear discriminant analysis were used to detect fine-scale vegetation patterns in the subalpine zone of the central Rocky Mountains, USA. The vegetation of this zone is a mosaic of conifer forests and treeless parks dominated by sagebrush (Artemisia spp.) and grasses. Previous work with pollen surface samples in the region has correlated modern pollen rain to broad-scale vegetation zones (e.g. steppe, montane forest, subalpine forest, and tundra), but little effort has been made to detect fine-scale (hundreds to thousands of meters) patterns within these vegetation zones. Previous theoretical studies suggest that vegetation patterns on the scale of hundreds of meters should be recorded in the...
Pollen and plant macrofossils from the Keystone Ironbog are used to document changes in species composition and the dynamics of the subalpine forest in western Colorado over the past 8000 years. Modern pollen spectra (particularly pollen influx), plant macrofossils, observations on modern species composition, and quantified densities and mean basal areas of forest trees are used to interpret the paleoecology of the forest. From 8000 to 2600 years ago the fen was surrounded by a subalpine forest. However, unlike the modern subalpine forest where Abies lasiocarpa (Hooker) Nuttall is slightly more abundant than Picea engelmannii (Parry) Engelmann, these Holocene forests had a greater dominance of P. engelmannii, perhaps...
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 (approximately 40 km). Growth of this isolate was markedly episodic and tracked multidecadal variability in precipitation. Initial colonization occurred by AD 1246, but expansion was forestalled by catastrophic drought (1250-1288), which we speculate produced extensive mortality of Utah Juniper (Juniperus osteosperma (Torr.) Little), the dominant tree at DJM for the previous approximately 8700 years. Pinyon then...
A quarry within the Cedar Mountain Formation in Mussentuchit Wash, Emery County, Utah, produced a fossil assemblage containing the remains of at least eight juvenile iguanodontid dinosaurs (Eolambia caroljonesa). The Cedar Mountain Formation lies stratigraphically between the Tithonian?Berriasian (Upper Jurassic) Brushy Basin Member of the Morrison Formation and the Cenomanian (Upper Cretaceous) Dakota Formation. Detailed stratigraphic, sedimentological, geochronological, palynological, and paleontological data have been collected along a measured section at the site of the Cifelli #2 Eolambia caroljonesa Quarry. These data provide a chronostratigraphic and a biostratigraphic framework for the Cedar Mountain Formation...
Strontium isotope sourcing has become a common and useful method for assigning sources to archaeological artifacts. In Chaco Canyon, an Ancestral Pueblo regional center in New Mexico, previous studies using these methods have suggested that significant portion of maize and wood originate in the Chuska Mountains region, 75 km to the East. In the present manuscript, these results were tested using both frequentist methods (to determine if geochemical sources can truly be differentiated) and Bayesian methods (to address uncertainty in geochemical source attribution). It was found that Chaco Canyon and the Chuska Mountain region are not easily distinguishable based on radiogenic strontium isotope values. The strontium...
Categories: Publication; Types: Citation; Tags: Agriculture, Anthropology, Archaeology, Archaeometry, Atoms, All tags...
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Diatom taxonomy, carbon and nitrogen stable isotope values, and algal pigment data from lake sediment layers dating back to 1600 Common Era (CE) for Sky Pond and The Loch in Rocky Mountain National Park.
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The 1995 - 2007 Ecosystem History of South Florida's Estuaries Database contains listings of all sites (modern and core), modern monitoring site survey information (water chemistry, floral and faunal data, bottom type, etc.), and published core data. Three general types of data are contained within this database: 1) Modern Field Data (1995-2007), 2) Master list of location information on all modern sites, and 3) Core data - faunal assemblages and location information. Data are available for modern sites and cores in the general areas of Florida Bay, Biscayne Bay, and the southwest (Florida) coastal mangrove estuaries. Specific sites in the Florida Bay area include Taylor Creek, Bob Allen Key, Russell Bank, Pass...
Categories: Data Release - Revised; Tags: 002, 004, 007, 008, 012, All tags...
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This dataset contains carbon and nitrogen stable isotope values, percent carbon and percent nitrogen, algal pigment data, and diatom taxonomy from lake sediment layers dating back to 1749 Common Era (CE) for Santa Fe lake, New Mexico. Subalpine and alpine lakes are typically sensitive indicators of anthropogenically driven global change. Lake sediment records in the western United States have documented increases in percent carbon (%C), percent nitrogen (%N), and primary productivity during the 20th century. Eutrophication of mountain lakes reflects the influences of atmospheric nutrient deposition and warming. We analyzed a short (49 cm) sediment core from Santa Fe Lake, NM to investigate patterns of change in...
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Data consist of census counts of Pliocene planktonic foraminifera from the lectostratotype of the Yorktown Formation at Rushmere Virginia, Rice's Pit, Yorktown, and the type section of the Morgarts Beach Member at Morgarts Beach, Virginia. In total, counts of individuals from 12 samples and 25 species are included.
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These files provide global coverage data describing boundary conditions for various aspects of the physical world representing several chosen times in Earth's history to be used as input data for climate modeling experiments. The raster data sets are provided in NetCDF format which is standard for climate modelling.
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 from episodic climatic events interacting with demographic and colonization events. This effect is compounded by the dependency of environmental sensitivity upon life-stage for many species. Climate variables often used in empirical niche models may become decoupled from the proximal variables that directly influence individuals and...
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Sixty packrat middens were collected in Canyonlands and Grand Canyon National Parks, and these series include sites north of areas that produced previous detailed series from the Colorado Plateau. The exceptionally long time series obtained from each of three sites (>48,000 C-14 yr BP to present) include some of the oldest middens yet discovered. Most middens contain a typical late-Wisconsinan glaciation mixture of mesic and xeric taxa, evidence that plant species responded to climate change by range adjustments of elevational distribution based oil individual criteria, Differences in elevational range from today for trees and shrubs ranged from no apparent change to as much as 1200 m difference. The oldest middens...
Abstract (from http://journal.frontiersin.org/article/10.3389/fpls.2014.00785/abstract): Fire is a key ecological process affecting vegetation dynamics and land cover. The characteristic frequency, size, and intensity of fire are driven by interactions between top-down climate-driven and bottom-up fuel-related processes. Disentangling climatic from non-climatic drivers of past fire regimes is a grand challenge in Earth systems science, and a topic where both paleoecology and ecological modeling have made substantial contributions. In this manuscript, we (1) review the use of sedimentary charcoal as a fire proxy and the methods used in charcoal-based fire history reconstructions; (2) identify existing techniques...
    map background search result map search result map 50,000 years of vegetation and climate history on the Colorado Plateau, Utah and Arizona, USA 1995 - 2007 Ecosystem History of South Florida's Estuaries Database (ver. 1.1, June 2022) Paleoecological data from The Loch and Sky Pond, Rocky Mountain National Park 2008 - Present Ecosystem History of South Florida's Estuaries Database (ver. 2.0, June 2022) Planktonic foraminifer census data from type section of Yorktown Formation at Rushmere, Virginia, USA Paleoecological data from sediment collected in 2020 from Santa Fe Lake, New Mexico Pliocene Model Intercomparison Project Phase 3 (PlioMIP3) Data Distribution Paleoecological data from sediment collected in 2020 from Santa Fe Lake, New Mexico Paleoecological data from The Loch and Sky Pond, Rocky Mountain National Park Planktonic foraminifer census data from type section of Yorktown Formation at Rushmere, Virginia, USA 1995 - 2007 Ecosystem History of South Florida's Estuaries Database (ver. 1.1, June 2022) 2008 - Present Ecosystem History of South Florida's Estuaries Database (ver. 2.0, June 2022) 50,000 years of vegetation and climate history on the Colorado Plateau, Utah and Arizona, USA Pliocene Model Intercomparison Project Phase 3 (PlioMIP3) Data Distribution