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Articles 1 - 7 of 7

Full-Text Articles in Physical Sciences and Mathematics

Aboveground Carbon Responses To Experimental And Natural Hurricane Impacts In A Subtropical Wet Forest In Puerto Rico, Hervé Chevalier, Nicholas V.L. Brokaw, Sheila E. Ward, Jess K. Zimmerman, Aaron B. Shiels, John Bithorn, Samuel Matta Carmona Jan 2022

Aboveground Carbon Responses To Experimental And Natural Hurricane Impacts In A Subtropical Wet Forest In Puerto Rico, Hervé Chevalier, Nicholas V.L. Brokaw, Sheila E. Ward, Jess K. Zimmerman, Aaron B. Shiels, John Bithorn, Samuel Matta Carmona

USDA Wildlife Services: Staff Publications

Climate change and disturbance make it difficult to project long-term patterns of carbon sequestration in tropical forests, but large ecosystem experiments in these forests can inform predictions. The Canopy Trimming Experiment (CTE) manipulates two key components of hurricane disturbance, canopy openness and detritus deposition, in a tropical forest in Puerto Rico. We documented how the CTE and a real hurricane affected tree recruitment, biomass, and aboveground carbon storage over 15 years. In the CTE treatments, we trimmed branches, but we did not fell trees. We expected that during the 14-year period after initial canopy trimming, regrowth of branches and stems …


Estimating Herbaceous Biomass Of Grassland Vegetation Using The Reference Unit Method, Eric D. Boyda, Jack L. Bulter, Lan Xu Dec 2015

Estimating Herbaceous Biomass Of Grassland Vegetation Using The Reference Unit Method, Eric D. Boyda, Jack L. Bulter, Lan Xu

The Prairie Naturalist

Aboveground net primary production provides valuable information on wildlife habitat, fire fuel loads, and forage availability. Aboveground net primary production in herbaceous plant communities is typically measured by clipping aboveground biomass. However, the high costs associated with physically harvesting plant biomass may prevent collecting sufficient data to account for natural spatial and temporal variability of vegetation at a landscape scale. Various double-sampling techniques have been developed to increase sample size while reducing cost. We applied a biomass estimation technique previously developed for estimating shrub biomass using representative samples or “reference units” to estimate herbaceous grassland biomass. Our reference units consisted …


Assessment Of A Rotenone Application Event At Mormon Island West Lake In Central Nebraska, Keith D. Koupal, Brian C. Peterson, Casey W. Schoenebeck Mar 2013

Assessment Of A Rotenone Application Event At Mormon Island West Lake In Central Nebraska, Keith D. Koupal, Brian C. Peterson, Casey W. Schoenebeck

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Fisheries managers applied rotenone to Mormon Island West in August of 2010 to renovate a fish community that was hypothesized to be unbalanced (i.e., dominated with gizzard shad and common carp) based on standardized survey results. We estimated species-specific biomass following the lake renovation to provide a baseline biomass estimate for a sand pit lake and to evaluate the effectiveness of standardized sampling gears. Gizzard shad (Dorosoma cepedianum) were abundant in all sampling gears, but mostly stock-size (>175 mm total length) and larger individuals were caught in gill and trap nets and sub-stock (≤175 mm total length) …


The Feasibility Of Producing Adequate Feedstock For Year-Round Cellulosic Ethanol Production In An Intensive Agricultural Fuelshed, Daniel R. Uden, Robert B. Mitchell, Craig R. Allen, Qingfeng Guan, Tim D. Mccoy Jan 2013

The Feasibility Of Producing Adequate Feedstock For Year-Round Cellulosic Ethanol Production In An Intensive Agricultural Fuelshed, Daniel R. Uden, Robert B. Mitchell, Craig R. Allen, Qingfeng Guan, Tim D. Mccoy

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

To date, cellulosic ethanol production has not been commercialized in the United States. However, government mandates aimed at increasing second-generation biofuel production could spur exploratory development in the cellulosic ethanol industry. We conducted an in-depth analysis of the fuelshed surrounding a starch-based ethanol plant near York, Nebraska that has the potential for cellulosic ethanol production. To assess the feasibility of supplying adequate biomass for year-round cellulosic ethanol production from residual maize (Zea mays) stover and bioenergy switchgrass (Panicum virgatum) within a 40-km road network service area of the existing ethanol plant, we identified ∼14,000 ha of marginally productive cropland within …


Grass And Canada Goldenrod (Solidago Canadensis) Competition And Implications For Management In The Northern Tallgrass Prairie, Alexander J. Smart, Gary E. Larson, Peter J. Bauman Jun 2012

Grass And Canada Goldenrod (Solidago Canadensis) Competition And Implications For Management In The Northern Tallgrass Prairie, Alexander J. Smart, Gary E. Larson, Peter J. Bauman

The Prairie Naturalist

Canada goldenrod (Solidago canadensis L.) is a native perennial forb that can form dense clonal patches and become weedy in pastures of the Northern Tallgrass Prairie Ecoregion. Our objectives were to determine 1) the competitive effects between Canada goldenrod and grass, 2) the relationship between Canada goldenrod stem density and grass biomass, and 3) the distribution of Canada goldenrod stem density at the pasture scale. We used regression analysis to develop a relationship between Canada goldenrod stem density and grass biomass. Additionally, we estimated the frequency distribution of Canada goldenrod stem density categories using three evenly distributed 100 × 100-m …


Effects Of Species, Water, And Nitrogen On Competition Among Three Prairie Grasses, Jerry L. Weatherford, Randall W. Myster Jun 2011

Effects Of Species, Water, And Nitrogen On Competition Among Three Prairie Grasses, Jerry L. Weatherford, Randall W. Myster

The Prairie Naturalist

We conducted an experiment to investigate effects of species, water (W), and nitrogen (N) on competition among little bluestem (Schizachyrium scoparium), sideoats grama (Bouteloua curtipendula), and indiangrass (Sorghastrum nutans). All biomass parameters and the root:shoot ratio of little bluestem were reduced by the presence off 1 of 2 other species, and its shoot biomass and total biomass were both increased by addition of N. Root and shoot biomass of sideoats grama were reduced by the presence of indiangrass and its total biomass was reduced by the presence of itself, whereas its shoot biomass was increased by addition of W at …


Winterkill And Biomass Of The Painted Turtle In A South Dakota Wetland, Steven G. Platt, Zannita Fast Horse, Warren Cross, Sylvio Mannel, Thomas R. Rainwater Sep 2008

Winterkill And Biomass Of The Painted Turtle In A South Dakota Wetland, Steven G. Platt, Zannita Fast Horse, Warren Cross, Sylvio Mannel, Thomas R. Rainwater

The Prairie Naturalist

Winterkill occurs when drought conditions expose hibernating turtles to desiccation and lethaly cold temperatures. Winterkill is thought to represent a major source of mortality in northern populations of the painted turtle (Chrysemys picta), but few field observations are available. We herein reported on catastrophic winterkill among western painted turtle (C. pieta bellii) at Limestone Butte Lake (LBL) in western South Dakota during the winter of 2003-2004. Additionally, we used the carcasses of winterkilled turtles (n = 86) to estimate the standing crop biomass of the painted turtle at LBL (0.6 kg/ha). This was the only estimate …