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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 transition, in part because it requires comparisons across dissimilar records [i.e. pollen from lacustrine sediments to the north and plant macrofossils from woodrat (Neotoma) middens to the south]. To overcome these limitations, we are extending the woodrat-midden record northward into the lowlands of the central Rocky Mountains. Published...
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Pollen was measured in ambient air by several methods and in wet atmospheric deposition samples at three monitoring sites in the National Atmospheric Deposition Program (NADP) National Trends Network. A method for counting pollen on filters was developed and provided pollen counts for NADP atmospheric wet-deposition samples and high-volume ambient air samplers (HVAS) for comparison with co-located traditional microscopy and PollenSense sensor counting methods during the 2021 pollen season. Air and precipitation samples were collected by the NADP and analyzed by the Wisconsin State Laboratory of Hygiene, in Madison, Wisconsin and Aerobiology Research Laboratories (Canada). Daily data were obtained from online summaries...
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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 rusty-patched bumble bee (Bombus affinis) is a listed species under the Endangered Species Act of the United States. While understood to be a highly generalist forager, little is known on the role that limited floral resources or shifting floral community composition could have played in B. affinis decline. Determining which floral species provide suitable B. affinis forage could assist conservation efforts where B. affinis persists, identify floral species for restoration efforts, or highlight regions to search for cryptic populations.
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...
Clastic and organic sediments exposed in two stream cutbanks above modern timberline in the headwaters of the Henrys Fork drainage record multiple episodes of fluvial, lacustrine and wetland deposition. The location of the upper Henrys Fork at the boundary between modern summer-wet/winter-dry and summer dry/winter-wet precipitation regimes suggests that changes in vegetation during the Holocene were due primarily to variations in growing-season temperature. A radiocarbon date of 9310 6 70 BP on a Salix fragment from the base of one exposure indicates that the upper reaches of the Henrys Fork were vegetated by riparian willows by the early Holocene. Four other dates on wood and bulk organics ranging up to 4070 6...
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Pollen morphology and pollen morphology in conjunction with other characteristics have elucidated the origin and evolution of various plant groups. Many studies of fossil pollen rarely discuss the effects of diagenesis and sample preparation on pollen characteristics. This paper examines the relationship of diagenesis, sample preparation (e.g., acetolysis), and staining techniques on the preservation and interpretation of pollen characteristics viewed with light, scanning and transmission electron microscopy. Based on empirical studies, different species under similar experimental conditions have different reflectance values, indicating the individual species respond differently to diagenetic events. The quantitative...
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A pollen addition experiment was conducted on the leaves of Croton setiger, a Californian forb. Pollen was added to leaves of randomly selected plants, and control plants had no pollen added. Over 2013 and 2014 the number of predatory and herbivorous insects were counted on each plant, and the number of damaged leaves and plant size were measured.
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...
A well-dated pollen record from a large lake located on the meadow?steppe ecotone provides a history of ecotone shift in response to monsoonal climate changes over the last 6000 years in the central Tibetan Plateau. The pollen record indicates that the ecotone shifted eastward during 6000?4900, 4400?3900, and 2800?1600 cal. yr BP when steppes occupied this region, whereas it shifted westward during the other intervals when the steppes were replaced by meadows. The quantitative reconstruction of paleoclimate derived from the pollen record shows that monsoon precipitation fluctuated around the present level over the last 6000 years in the central Tibetan Plateau. Three major drought episodes of 5600?4900, 4400?3900,...
Fossil remains of Euceratherium collinum (extinct shrub-ox) have been found throughout North America, including the Grand Canyon. Recent finds from the Escalante River Basin in southern Utah further extend the animal's range into the heart of the Colorado Plateau. E. collinum teeth and a metapodial condyle (foot bone) have been recovered in association with large distinctively shaped dung pellets, a morphology similar to a ?Hershey's Kiss? (HK), from a late Pleistocene dung layer in Bechan Cave. HK dung pellets have also been recovered from other alcoves in the Escalante River Basin including Willow and Fortymile canyons. Detailed analyses of the HK pellets confirmed them to be E. collinum and indicate a browser-type...
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 transition, in part because it requires comparisons across dissimilar records [i.e. pollen from lacustrine sediments to the north and plant macrofossils from woodrat (Neotoma) middens to the south]. To overcome these limitations, we are extending the woodrat-midden record northward into the lowlands of the central Rocky Mountains.
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In this study US Geological Survey scientists collected pollen samples from honey bee (Apis mellifera) colonies distributed across North Dakota, South Dakota, and Minnesota, in 2015 and 2016. Sequencing of nuclear ribosomal loci was used to determine the number and abundance of flowering plant taxa. The data contain counts of Operational Taxonomic Unit (OTU) reads of honey bee collected pollen from apiary locations throughout the growing season.
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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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Here we compare pollen identification results derived from light microscopy and DNA sequencing techniques of a robust number of samples collected from honey bee colonies embedded within intensive agricultural landscapes in the Northern Great Plains. We collected pollen samples from colonies within 6 apiaries in 2010 and 2011. For each pollen sample, we identified pollen grains via light microscopy and provide the number of grain counts-per-million. A separate aliquot of each pollen sample subjected to light microscope identification was also used for DNA sequencing analysis. We provide the plant operational taxonomic unit (OTU) for all base pair reads as the number of reads-per-million.


    map background search result map search result map A comparison of honey bee-collected pollen from working agricultural lands using light microscopy and ITS metabarcoding datasets 1995 - 2007 Ecosystem History of South Florida's Estuaries Database (ver. 1.1, June 2022) Croton setiger predators, herbivores, and damage collected in California 2013-2014 2008 - Present Ecosystem History of South Florida's Estuaries Database (ver. 2.0, June 2022) Dataset: Molecular identification of honey bee collected pollen in the Northern Great Plains, North America, 2015-2016 Rusty Patched Bumble Bee Pollen Metagenome Reflectance and spectral fluorescence data from the effect of diagenesis on the preservation of morphology and ultrastructural features of pollen National Atmospheric Deposition Program Pollen Study Data for 2021 Pollen Season Croton setiger predators, herbivores, and damage collected in California 2013-2014 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) A comparison of honey bee-collected pollen from working agricultural lands using light microscopy and ITS metabarcoding datasets Dataset: Molecular identification of honey bee collected pollen in the Northern Great Plains, North America, 2015-2016 National Atmospheric Deposition Program Pollen Study Data for 2021 Pollen Season Rusty Patched Bumble Bee Pollen Metagenome Reflectance and spectral fluorescence data from the effect of diagenesis on the preservation of morphology and ultrastructural features of pollen