Physical Sciences and Mathematics Commons^™

Terrestrial Ecosystem Process Model Biome-Bgcmuso V4.0: Summary Of Improvements And New Modeling Possibilities, Dóra Hidy, Zoltán Barcza, Hrvoje Marjanovi´C, Maša Zorana Ostrogovi´C Sever, Laura Dobor, Györgyi Gelybó, Nándor Fodor, Krisztina Pintér, Galina Churkina, Steven Running, Peter Thornton, Gianni Bellocchi, László Haszpra, Ferenc Horváth, Andrew E. Suyker, Zoltán Nagy

Papers in Natural Resources

The process-based biogeochemical model Biome- BGC was enhanced to improve its ability to simulate carbon, nitrogen, and water cycles of various terrestrial ecosystems under contrasting management activities. Biome-BGC version 4.1.1 was used as a base model. Improvements included addition of new modules such as the multilayer soil module, implementation of processes related to soil moisture and nitrogen balance, soil-moisture-related plant senescence, and phenological development. Vegetation management modules with annually varying options were also implemented to simulate management practices of grasslands (mowing, grazing), croplands (ploughing, fertilizer application, planting, harvesting), and forests (thinning). New carbon and nitrogen pools have been defined to …

Freshwater Vertebrate And Invertebrate Diversity Patterns In An Andean-Amazon Basin: Implications For Conservation Efforts, Janeth Lessmann, Juan M. Guayasamin, Kayce L. Casner, Alexander S. Flecker, W. Chris Funk, Cameron K. Ghalambor, Brian A. Gill, Iván Jácome- Negrete, Boris C. Kondratieff, Leroy N. Poff, José Schreckinger, Steven A. Thomas, Eduardo Toral-Contreras, Kelly R. Zamudio, Andrea C. Encalada

Papers in Natural Resources

The Napo Basin in Ecuador is an important drainage of the Amazon Basin, the most biodiverse ecosystem for freshwater species. At the same time, this basin has conspicuous information gaps on its biodiversity patterns and human threats. Here, we estimated the diversity distribution patterns of freshwater vertebrates and invertebrates in the Napo Basin, as a tool for present and future management and conservation efforts. Also, we assessed the spatial congruence of the diversity patterns observed between aquatic vertebrates and invertebrates. For this, we compiled occurrence records for 481 freshwater vertebrate species (amphibians, birds, mammals, reptiles, and fish), and 54 invertebrate …

Are We Preparing The Next Generation Of Fisheries Professionals To Succeed In Their Careers?: A Survey Of Afs Members, Steve L. Mcmullin, Vic Dicenzo, Ron Essig, Craig Bonds, Robin L. Debruyne, Mark A. Kaemingk, Martha Mather, Christopher A. Myrick, Quinton E. Phelps, Trent M. Sutton, James R. Triplett

Papers in Natural Resources

Natural resource professionals have frequently criticized universities for poorly preparing graduates to succeed in their jobs. We surveyed members of the American Fisheries Society to determine which job skills and knowledge of academic topics employers, students, and university faculty members deemed most important to early-career success of fisheries professionals. Respondents also rated proficiency of recently hired, entry-level professionals (employers) on how well their programs prepared them for career success (students and faculty) in those same job skills and academic topics. Critical thinking and written and oral communication skills topped the list of important skills and academic topics. Employers perceived recent …

Examining The Relevancy And Utility Of The American Fisheries Society Certification Program To Prepare Future Fisheries Professionals, Mark A. Kaemingk, Ron Essig, Steve L. Mcmullin, Craig Bonds, Robin L. Debruyne, Christopher A. Myrick, Quinton E. Phelps, Trent M. Sutton, James R. Triplett

Papers in Natural Resources

Fisheries science is a diverse field that requires individuals to be knowledgeable in many disciplines in addition to fisheries (e.g., economics, sociology, political science, chemistry; Kelso and Murphy 1988). This challenges students attempting to enter a career in fisheries, as well as academic institutions and eventual employers, to develop both depth and breadth of knowledge needed to succeed in the profession (Oglesby and Krueger 1989). The preparedness and competency of young professionals entering the workforce has long been a problem (Stauffer and McMullin 2009). Several constraints and ongoing challenges facing the profession have continued to magnify these issues over time …

Survival And Cause-Specific Mortality Of Female Eastern Wild Turkeys In Two Frequently-Burned Longleaf Pine Savannas, Andrew R. Little, John F. Benson, Michael J. Chamberlain, L. Mike Conner, Robert J. Warren

Papers in Natural Resources

Longleaf pine savannas have declined throughout the southeastern United States due to land-use change. Fortunately, natural resource professionals are currently restoring these ecologically and economically important savannas. Although efforts are underway to restore longleaf pine savannas, little information exists on female eastern wild turkey Meleagris gallopavo silvestris population dynamics in these systems. Therefore, we evaluated survival and cause-specific mortality of female eastern wild turkeys in two longleaf pine savannas in southwestern Georgia. We radio-marked 126 female wild turkeys during 2010–2013 and monitored their survival; 66 (52.4%) radio-marked females died during the study. We estimated causes of death for 37 mortality …

Habitat Selection Of Wild Turkeys In Burned Longleaf Pine Savannas, Andrew R. Little, Michael J. Chamberlain, L. Mike Conner, Robert J. Warren

Papers in Natural Resources

Frequent prescribed fire (≤3 yr) and selective harvest of off-site hardwoods are the primary restoration and management tools for pine (Pinus spp.) savannas in the southeastern United States. However, a knowledge gap exists in our understanding of eastern wild turkey (Meleagris gallopavo silvestris) habitat selection in longleaf pine savannas and research is warranted to direct our future management decisions. Therefore, we investigated habitat selection of female turkeys in 2 longleaf pine savanna systems managed by frequent fire in southwestern Georgia during 2011–2013. We observed differential habitat selection across 2 scales (study area and seasonal area of use) …

Carbon And Energy Fluxes In Cropland Ecosystems: A Model-Data Comparison, Erandathie Lokupitiya, A. S. Denning, K. Schaefer, D. Ricciuto, R. Anderson, M. A. Arain, Colorado State University, A. G. Barr, G. Chen, J. M. Chen, P. Ciais, D. R. Cook, M. Dietze, M. El Maayar, M. Fischer, University Of Alberta, D. Hollinger, C. Izaurralde, A. Jain, C. Kucharik, Z. Li, S. Liu, L. Li, R. Matamala, P. Peylin, D. Price, S. W. Running, A. Sahoo, M. Sprintsin, Andrew Suyker, H. Tian, C. Tonitto, M. Torn, Hans Verbeeck, Shashi Verma, Y. Xue

Papers in Natural Resources

Croplands are highly productive ecosystems that contribute to land–atmosphere exchange of carbon, energy, and water during their short growing seasons. We evaluated and compared net ecosystem exchange (NEE), latent heat flux (LE), and sensible heat flux (H) simulated by a suite of ecosystem models at five agricultural eddy covariance flux tower sites in the central United States as part of the North American Carbon Program Site Synthesis project. Most of the models overestimated H and underestimated LE during the growing season, leading to overall higher Bowen ratios compared to the observations. Most models systematically under predicted NEE, especially at rain-fed …

Submerged Area Of Typical Torrential Flood And Debris-Flow Disasters In Mengzong Gully, China, Ai-Di Huo, Wen-Ke Guan, Jian Dang, Tian-Zhong Wu, Hainiken Shantai, Wei Wang, Michael W. Van Liew

Papers in Natural Resources

The torrential flooding and debris flow disasters associated with global climate change pose not only serious threat to individual lives and property, but also impact economic development. Accurately simulating flood scenarios can help to reduce the losses caused by torrential flooding and debris flow by making early warning, evacuation planning, and risk analysis possible. In this study, HEC-RAS software and HEC-GeoRAS module were employed in GIS (geographic information system) to simulate the flood overtopping in the Mengzong Gully of Batang River in flood scenarios occurring once in 20, 50, and 100 years, respectively. The simulated floods provided valuable information including …

Fluctuating Survival Selection Explains Variation In Avian Group Size, Charles R. Brown, Mary Bomberger Brown, Erin A. Roche, Valerie A. O'Brien, Catherine E. Page

Papers in Natural Resources

Most animal groups vary extensively in size. Because individuals in certain sizes of groups often have higher apparent fitness than those in other groups, why wide group size variation persists in most populations remains unexplained. We used a 30-y mark– recapture study of colonially breeding cliff swallows (Petrochelidon pyrrhonota) to show that the survival advantages of different colony sizes fluctuated among years. Colony size was under both stabilizing and directional selection in different years, and reversals in the sign of directional selection regularly occurred. Directional selection was predicted in part by drought conditions: birds in larger colonies tended …

Eastern Wild Turkey Nest Site Selection In Two Frequently Burned Pine Savannas, Andrew R. Little, Nathan P. Nibbelink, Michael J. Chamberlain, L. Mike Conner, Robert J. Warren

Papers in Natural Resources

Introduction: Reproductive success is a critical factor affecting avian demographics and can be influenced by many factors including nesting chronology, predation risk, and fine-scale nest site selection.

Methods: We modeled the relative influences of habitat-related covariates at six spatial scales (nest site: 15-, 40-, 80-, 120-, 160-, and 200-m radii) on Eastern wild turkey (Meleagris gallopavo silvestris) nest site selection in two pine savannas managed by frequent prescribed fire (≤3 years) in southwestern Georgia during 2011–2013.

Results: Nest site (15-m scale) habitat metrics (mean visual obstruction [cm] and canopy closure [%]) had the greatest influence on nest site …

Does Predation Influence The Seasonal And Diel Timing Of Moose Calving In Central Ontario, Canada?, Brent R. Patterson, Kenneth J. Mills, Kevin R. Middel, John F. Benson, Martyn E. Obbard

Papers in Natural Resources

Birth synchrony is well documented among ungulates and is hypothesised to maximize neonate survival, either by minimizing the risk of predation through predator swamping or by synchronising birthing with increased seasonal food availability. We used encapsulated vaginal implant transmitters to locate and capture neonatal moose calves and document the seasonal and diel timing of parturition in two adjacent study areas with different predation pressure in central Ontario, Canada. We tested the hypothesis that predation promotes earlier and more synchronous birth of moose calves. Across both areas, proportionately more births occurred during the afternoon and fewer than expected occurred overnight. Mean …

Acoustic Detection Reveals Fine-Scale Distributions Of Myotis Lucifugus, Myotis Septentrionalis, And Perimyotis Subflavus In Eastern Nebraska, Jeremy A. White, Cliff Lemen, Patricia Freeman

Papers in Natural Resources

ABSTRACT.—Before white-nose syndrome arrives in Nebraska, it is important to document the preexposure distributions of cave bats in the state. We examined the distributions of Myotis lucifugus (little brown myotis), Myotis septentrionalis (northern long-eared myotis), and Perimyotis subflavus (tri-colored bat) in eastern Nebraska by setting acoustic detectors for a single night at 105 sites in wooded habitats during summers of 2012 and 2014. We compared 2 methods of determining presence at each site. Results of our analyses are fine-scale distributional maps for these bats and some range extensions from published records. Results for M. septentrionalis and P. subflavus are largely …

Using Cosmic-Ray Neutron Probes To Monitor Landscape Scale Soil Water Content In Mixed Land Use Agricultural Systems, Trenton E. Franz, Ammar Wahbi, Mariette Vreugdenhil, Georg Weltin, Lee Hang, Markus Oismueller, Peter Strauss, Gerd Dercon, Darin Desilets

Papers in Natural Resources

With an ever-increasing demand for natural resources and the societal need to understand and predict natural disasters, soil water content (SWC) observations remain a critical variable to monitor in order to optimally allocate resources, establish early warning systems, and improve weather forecasts.However, routine agricultural production practices of soil cultivation, planting, and harvest make the operation andmaintenance of direct contact point sensors for long-termmonitoring challenging. In this work, we explore the use of the newly established Cosmic-Ray Neutron Probe (CRNP) and method to monitor landscape average SWC in a mixed agricultural land use systemin northeastAustria.Thecalibrated CRNP landscape SWC values compare well …

The Sensitivity Of Carbon Exchanges In Great Plains Grasslands To Precipitation Variability, M.D. Petrie, N. A. Brunsell, R. Vargas, Scott L. Collins, L.B. Flanagan, N.P. Hanan, M.E. Litvak, A. E. Suyker

Papers in Natural Resources

In the Great Plains, grassland carbon dynamics differ across broad gradients of precipitation and temperature, yet finer-scale variation in these variables may also affect grassland processes. Despite the importance of grasslands, there is little information on how fine-scale relationships compare between them regionally. We compared grassland C exchanges, energy partitioning and precipitation variability in eight sites in the eastern and western Great Plains using eddy covariance and meteorological data. During our study, both eastern and western grasslands varied between an average net carbon sink and a net source. Eastern grasslands had a moderate vapor pressure deficit (VPD = 0.95 kPa) …

Closing The Water Balance With Cosmic-Ray Soil Moisture Measurements And Assessing Their Relation To Evapotranspiration In Two Semiarid Watersheds, A. P. Schreiner-Mcgraw, E. R. Vivoni, G. Mascaro, Trenton E. Franz

Papers in Natural Resources

Soil moisture dynamics reflect the complex interactions of meteorological conditions with soil, vegetation and terrain properties. In this study, intermediate-scale soil moisture estimates from the cosmic-ray neutron sensing (CRNS) method are evaluated for two semiarid ecosystems in the southwestern United States: a mesquite savanna at the Santa Rita Experimental Range (SRER) and a mixed shrubland at the Jornada Experimental Range (JER). Evaluations of the CRNS method are performed for small watersheds instrumented with a distributed sensor network consisting of soil moisture sensor profiles, an eddy covariance tower, and runoff flumes used to close the water balance. We found a very …

Current Topics In Avian Conservation Genetics With Special Reference To The Southwestern Willow Flycatcher, R.M. Zink

Papers in Natural Resources

No abstract provided.

Seasonal Relationships Between Foliar Moisture Content, Heat Content And Biochemistry Of Lodgepole Pine And Big Sagebrush Foliage, Yi Qi, W. Matt Jolly, Philip E. Dennison, Rachael C. Kropp

Papers in Natural Resources

No abstract provided.

Temporal Variability In Aboveground Plant Biomass Decreases As Spatial Variability Increases, Devan Allen Mcgranahan, Torre J. Hovick, R. Dwayne Elmore, David M. Engle, Samuel D. Fuhlendorf, Stephen L. Winter, James R. Miller, Diane M. Debinski

Papers in Natural Resources

Ecological theory predicts that diversity decreases variability in ecosystem function. We predict that, at the landscape scale, spatial variability created by a mosaic of contrasting patches that differ in time since disturbance will decrease temporal variability in aboveground plant biomass. Using data from a multi-year study of seven grazed tallgrass prairie landscapes, each experimentally managed for one to eight patches, we show that increased spatial variability driven by spatially patchy fire and herbivory reduces temporal variability in aboveground plant biomass. This pattern is associated with statistical evidence for the portfolio effect and a positive relationship between temporal variability and functional …

Monitoring Grassland Seasonal Carbon Dynamics, By Integrating Modis Ndvi, Proximal Optical Sampling, And Eddy Covariance Measurements, Enrica Nestola, Carlo Calfapietra, Craig A. Emmerton, Christopher Y. S. Wong, Donnette R. Thayer, John A. Gamon

Papers in Natural Resources

This study evaluated the seasonal productivity of a prairie grassland (Mattheis Ranch, in Alberta, Canada) using a combination of remote sensing, eddy covariance, and field sampling collected in 2012–2013. A primary objective was to evaluate different ways of parameterizing the light-use efficiency (LUE) model for assessing net ecosystem fluxes at two sites with contrasting productivity. Three variations on the NDVI (Normalized Difference Vegetation Index), differing by formula and footprint, were derived: (1) a narrow-band NDVI (NDVI680,800, derived from mobile field spectrometer readings); (2) a broad-band proxy NDVI (derived from an automated optical phenology station consisting of broad-band radiometers); and (3) …

Avian Interactions With Renewable Energy Infrastructure: An Update, Jennifer A. Smith, James F. Dwyer

Papers in Natural Resources

Energy infrastructure is widespread worldwide. Renewable energy technologies, which are expanding their footprint on the landscape and their contribution to energy availability, represent a different kind of infrastructure from extractive energy technologies. Although renewable energy sources may offer a ‘greener alternative’ to traditional extractive energy sources, mounting evidence suggests that renewable energy infrastructure, and the transmission lines needed to convey energy from renewable energy facilities to users, may impact birds. Peer-reviewed literature historically has focused on the direct effects of electrocution and, to a lesser extent, collisions with overhead power systems, and on avian collisions at wind energy facilities, with …

Temporal Variability In Aboveground Plant Biomass Decreases As Spatial Variability Increases, Devan Allen Mcgranahan, Torre J. Hovick, R. Dwayne Elmore, David M. Engle, Samuel D. Fuhlendorf, Stephen L. Winter, James R. Miller, Diane M. Debinski

Papers in Natural Resources

Ecological theory predicts that diversity decreases variability in ecosystem function. We predict that, at the landscape scale, spatial variability created by a mosaic of contrasting patches that differ in time since disturbance will decrease temporal variability in aboveground plant biomass. Using data from a multi-year study of seven grazed tallgrass prairie landscapes, each experimentally managed for one to eight patches, we show that increased spatial variability driven by spatially patchy fire and herbivory reduces temporal variability in aboveground plant biomass. This pattern is associated with statistical evidence for the portfolio effect and a positive relationship between temporal variability and functional …

A Remotely Sensed Pigment Index Reveals Photosynthetic Phenology In Evergreen Conifers, John A. Gamon, K. Fred Huemmrich, Christopher Y.S. Wong, Ingo Ensminger, Steven Garrity, David Y. Hollinger, Asko Noormets, Josep Peñuelas

Papers in Natural Resources

In evergreen conifers, where the foliage amount changes little with season, accurate detection of the underlying “photosynthetic phenology” from satellite remote sensing has been difficult, presenting challenges for global models of ecosystem carbon uptake. Here, we report a close correspondence between seasonally changing foliar pigment levels, expressed as chlorophyll/carotenoid ratios, and evergreen photosynthetic activity, leading to a “chlorophyll/carotenoid index” (CCI) that tracks evergreen photosynthesis at multiple spatial scales. When calculated from NASA’s Moderate Resolution Imaging Spectroradiometer satellite sensor, the CCI closely follows the seasonal patterns of daily gross primary productivity of evergreen conifer stands measured by eddy covariance. This discovery …

Informative Spectral Bands For Remote Green Lai Estimation In C3 And C4 Crops, Oz Kira, Anthony L. Nguy-Robertson, Timothy J. Arkebauer, Raphael Linker, Anatoly A. Gitelson

Papers in Natural Resources

Green leaf area index (LAI) provides insight into the productivity, physiological and phenological status of vegetation. Measurement of spectral reflectance offers a fast and nondestructive estimation of green LAI. A number of methods have been used for the estimation of green LAI; however, the specific spectral bands employed varied widely among the methods and data used. Our objectives were (i) to find informative spectral bands retained in three types of methods, neural network (NN), partial least squares (PLS) regression and vegetation indices (VI), for estimating green LAI in maize (a C4 species) and soybean (a C3 species); (ii) to assess …

Flight Initiation Distances Of Nesting Piping Plovers (Charadrius Melodus) In Response To Human Disturbance, Joel G. Jorgensen, Lauren R. Dinan, Mary Bomberger Brown

Papers in Natural Resources

Birds frequently interact with people when they occur in coupled human-ecological or anthropogenic environments, which makes the protection of legally protected species a challenge. Flight initiation distances (FIDs) are often used to inform development of appropriate buffer distances required for human exclusion zones used to protect birds nesting in anthropogenic landscapes. Piping Plovers (Charadrius melodus) are protected by the Endangered Species Act in the United States and often nest in areas used by humans. Studies evaluating Piping Plover FIDs are limited and implementation of exclusion zones has been inconsistent across the species’ range. We measured Piping Plover response …

Basic Forms And Orbit Spaces:A Diffeological Approach, Yael Karshon, Jordan Watts

Papers in Natural Resources

No abstract provided.

Foraging Decisions Underlying Restricted Space Use: Effects Of Fire And Forage Maturation On Large Herbivore Nutrient Uptake, Edward J. Raynor, Anthony Joern, Jesse B. Nippert, John M. Briggs

Papers in Natural Resources

Recent models suggest that herbivores optimize nutrient intake by selecting patches of low to intermediate vegetation biomass. We assessed the application of this hypothesis to plains bison (Bison bison) in an experimental grassland managed with fire by estimating daily rates of nutrient intake in relation to grass biomass and by measuring patch selection in experimental watersheds in which grass biomass was manipulated by prescribed burning. Digestible crude protein content of grass declined linearly with increasing biomass, and the mean digestible protein content relative to grass biomass was greater in burned watersheds than watersheds not burned that spring (intercept; F_{1,251 …}

Consequences Of Hatch Phenology On Stages Of Fish Recruitment, David M. Bogner, Mark A. Kaemingk, Melissa R. Wuellner

Papers in Natural Resources

Little is known about how hatch phenology (e.g., the start, peak, and duration of hatching) could influence subsequent recruitment of freshwater fishes into a population. We used two commonly sympatric fish species that exhibit different hatching phenologies to examine recruitment across multiple life stages. Nine yellow perch (Perca flavescens) and bluegill (Lepomis macrochirus) annual cohorts were sampled from 2004 through 2013 across larval, age-0, age-1, and age-2 life stages in a Nebraska (U.S.A.) Sandhill lake. Yellow perch hatched earlier in the season and displayed a more truncated hatch duration compared to bluegill. The timing of hatch …

Winter Diet And Hunting Success Of Canada Lynx In Colorado, Jacob S. Ivan, Tanya M. Shenk

Papers in Natural Resources

Information regarding the diet of Canada lynx (Lynx canadensis) at the southernmost extent of its range is critical for managing the species under current and predicted climate conditions. Therefore, from 1999–2009, we investigated winter diet and hunting strategies of Canada lynx in Colorado, USA by tracking individuals in the snow to identify sites where lynx encountered and killed prey. Similar to other parts of lynx range, snowshoe hares (Lepus americanus) were the primary winter food in Colorado, especially when considering total biomass consumed. Red squirrels (Tamiasciurus hudsonicus) comprised the bulk of the remaining food …

Impacts Of Human Hunting On Spatial Behavior Of White-Tailed Deer (Odocoileus Virginianus), Sierra A. Marantz, Jed A. Long, Stephen L. Webb, Kenneth L. Gee, Andrew R. Little, Stephen Demarais

Papers in Natural Resources

Predators can influence populations through top-down effects, but most large predators have been extirpated from the range of white-tailed deer (Odocoileus virginianus (Zimmermann, 1780)). Hunters have filled this predatory role, but also can indirectly influence prey species. Indirect behavioral responses can include altered resource selection, space use, or movement. Herein, we developed a controlled study that contained both temporal and spatial risk levels to assess how deer behavior changes relative to temporal periods of risk. Total distance travelled and microrange area over 2-day periods were used to determine the general effects of hunting season on deer spatial behavior. Generally, distance …

Integrated Analysis Of Productivity And Biodiversity In A Southern Alberta Prairie, Ran Wang, John A. Gamon, Craig A. Emmerton, Haitao Li, Enrica Nestola, Gilberto Z. Pastorello, Olaf Menzer

Papers in Natural Resources

Grasslands play important roles in ecosystem production and support a large farming and grazing industry. An accurate and efficient way is needed to estimate grassland health and production for monitoring and adjusting management to get sustainable products and other ecosystem services. Previous studies of grasslands have shown varying relationships between productivity and biodiversity, with most showing either a positive or a hump-shaped relationship where productivity peaks at intermediate diversity. In this study, we used airborne imaging spectrometry combined with ground sampling and eddy covariance measurements to estimate the spatial pattern of production and biodiversity for two sites of contrasting productivity …