The Uncertain Climate Footprint Of Wetlands Under
Human Pressure,
2015
European Commission, Joint Research Center, Institute for Environment and Sustainability
The Uncertain Climate Footprint Of Wetlands Under Human Pressure, Ana Maria Roxana Petrescu, Annalea Lohila, Juha-Pekka Tuovinen, Dennis D. Baldocchi, Ankur R. Desai, Nigel T. Roulet, Timo Vesala, Albertus Johannes Dolman, Walter C. Oechel, Barbara Marcolla, Thomas Friborg, Janne Rinne, Jaclyn Hatala Matthes, Lutz Merbold, Ana Meijide, Gerard Kiely, Matteo Sottocornola, Torsten Sachs, Donatella Zona, Andrej Varlagin, Derrick Y.F. Lai, Elmar Veenendaal, Frans-Jan W. Parmentier, Ute Skiba, Magnus Land, Arjan Hensen, Jacobus Van Huissteden, Lawrence B. Flanagan, Narasinha J. Shurpali, Thomas Grünwald, Elyn R. Humphreys, Marcin Jackowicz-Korczynski, Mika A. Aurela, Tuomas Laurila, Carsten Grüning, Chiara A.R. Corradi, Arina P. Schrier-Uijl, Torben R. Christensen, Mikkel P. Tamstorf, Mikhail Mastepanov, Pertti J. Martikainen, Shashi Verma, Christian Bernhofer, Alessandro Cescatti
School of Natural Resources: Faculty Publications
Significant climate risks are associated with a positive carbon–temperature feedback in northern latitude carbon-rich ecosystems,making an accurate analysis of human impacts on the net greenhouse gas balance of wetlands a priority. Here, we provide a coherent assessment of the climate footprint of a network of wetland sites based on simultaneous and quasi-continuous ecosystem observations of CO2 and CH4 fluxes. Experimental areas are located both in natural and in managed wetlands and cover a wide range of climatic regions, ecosystem types, and management practices. Based on direct observations we predict that sustained CH4 emissions in natural ecosystems are …
Thermal-Based Modeling Of Coupled Carbon, Water, And Energy Fluxes Using Nominal Light Use Efficiencies Constrained By Leaf Chlorophyll Observations, M. A. Schull, M. C. Anderson, R. Houborg, Anatoly A. Gitelson, W. P. Kustas
School of Natural Resources: Faculty Publications
Recent studies have shown that estimates of leaf chlorophyll content (Chl), defined as the combined mass of chlorophyll a and chlorophyll b per unit leaf area, can be useful for constraining estimates of canopy light use efficiency (LUE). Canopy LUE describes the amount of carbon assimilated by a vegetative canopy for a given amount of absorbed photosynthetically active radiation (APAR) and is a key parameter for modeling land-surface carbon fluxes. A carbonenabled version of the remote-sensing-based two-source energy balance (TSEB) model simulates coupled canopy transpiration and carbon assimilation using an analytical submodel of canopy resistance constrained by inputs of nominal …
Phycocyanin-Specific Absorption Coefficient: Eliminating The Effect Of Chlorophylls Absorption,
2015
Kinneret Limnological Laboratory
Phycocyanin-Specific Absorption Coefficient: Eliminating The Effect Of Chlorophylls Absorption, Y. Z. Yacobi, J. Köhler, F. Leunert, Anatoly A. Gitelson
School of Natural Resources: Faculty Publications
The applicability of algorithms for estimation of phycocyanin (PC) concentration based on light spectral reflectance heavily depends on the specific absorption of the pigment. But the determination of PC-specific absorption coefficient is not a straightforward task, as PC optical activity is overlapped by absorption of chlorophylls. The aim of our study was to determine a*PC(625)—the specific absorption coefficient of PC at 625 nm, in samples with PC concentrations ranging from 0.5 mg m-3 to 126.4 mg m-3 and varying proportions of chlorophylls a, b, and c in the samples. The effect of chlorophylls was subtracted from …
Modeling Actual Evapotranspiration With Routine
Meteorological Variables In The Data-Scarce
Region Of The Tibetan Plateau: Comparisons
And Implications,
2015
Chinese Academy of Sciences, Beijing, China
Modeling Actual Evapotranspiration With Routine Meteorological Variables In The Data-Scarce Region Of The Tibetan Plateau: Comparisons And Implications, Ning Ma, Yinsheng Zhang, Chong-Yu Xu, Jozsef Szilagyi
School of Natural Resources: Faculty Publications
Quantitative estimation of actual evapotranspiration (ETa) by in situ measurements and mathematical modeling is a fundamental task for physical understanding of ETa as well as the feedback mechanisms between land and the ambient atmosphere. However, the ETa information in the Tibetan Plateau (TP) has been greatly impeded by the extremely sparse ground observation network in the region. Approaches for estimating ETa solely from routine meteorological variables are therefore important for investigating spatiotemporal variations of ETa in the data-scarce region of the TP. Motivated by this need, the complementary relationship (CR) and Penman-Monteith approaches were evaluated against in …
Remote Sensing Of Drought: Progress, Challenges
And Opportunities,
2015
University of California, Irvine
Remote Sensing Of Drought: Progress, Challenges And Opportunities, A. Aghakouchak, A. Farahmand, F. S. Melton, J. Teixeira, M. C. Anderson, Brian D. Wardlow, C. R. Hain
School of Natural Resources: Faculty Publications
This review surveys current and emerging drought monitoring approaches using satellite remote sensing observations from climatological and ecosystem perspectives. We argue that satellite observations not currently used for operational drought monitoring, such as near-surface air relative humidity data from the Atmospheric Infrared Sounder mission, provide opportunities to improve early drought warning. Current and future satellite missions offer opportunities to develop composite and multi-indicator drought models. While there are immense opportunities, there are major challenges including data continuity, unquantified uncertainty, sensor changes, and community acceptability. One of the major limitations of many of the currently available satellite observations is their short …
Evaluating The Complementary Relationship Of
Evapotranspiration In The Alpine Steppe Of The Tibetan Plateau,
2015
Chinese Academy of Sciences
Evaluating The Complementary Relationship Of Evapotranspiration In The Alpine Steppe Of The Tibetan Plateau, Ning Ma, Yinsheng Zhang, Jozsef Szilagyi, Yanhong Guo, Jianqing Zhai, Haifeng Gao
School of Natural Resources: Faculty Publications
The complementary relationship (CR) of evapotranspiration allows the estimation of the actual evapotranspiration rate (ETa) of the land surface using only routine meteorological data, which is of great importance in the Tibetan Plateau (TP) due to its sparse observation network. With the highest in situ automatic climate observation system in a typical semiarid alpine steppe region of the TP, the wind function of Penman was replaced by one based on the Monin-Obukhov Similarity theory for calculating the potential evapotranspiration rate (ETp); the Priestley-Taylor coefficient, a, was estimated using observations in wet days; and the slope of …
Complementary-Relationship-Based 30 Year Normals
(1981–2010) Of Monthly Latent Heat Fluxes Across The
Contiguous United States,
2015
University of Nebraska - Lincoln
Complementary-Relationship-Based 30 Year Normals (1981–2010) Of Monthly Latent Heat Fluxes Across The Contiguous United States, Jozsef Szilagyi
School of Natural Resources: Faculty Publications
Thirty year normal (1981–2010) monthly latent heat fluxes (ET) over the conterminous United States were estimated by a modified Advection-Aridity model from North American Regional Reanalysis (NARR) radiation and wind as well as Parameter-Elevation Regressions on Independent Slopes Model (PRISM) air and dew-point temperature data. Mean annual ET values were calibrated with PRISM precipitation (P) and validated against United States Geological Survey runoff (Q) data. At the six-digit Hydrologic Unit Code level (sample size of 334) the estimated 30 year normal runoff (P – ET) had a bias of 18 mm yr-1, a root-mean-square error of …
Atmospheric Circulation Processes Contributing
To A Multidecadal Variation In Reconstructed
And Modeled Indian Monsoon Precipitation,
2015
University of Nebraska - Lincoln
Atmospheric Circulation Processes Contributing To A Multidecadal Variation In Reconstructed And Modeled Indian Monsoon Precipitation, Qianru Wu, Qi Hu
School of Natural Resources: Faculty Publications
An analysis of the recently reconstructed gridded May–September total precipitation in the Indian monsoon region for the past half millennium discloses significant variations at multidecadal timescales. Meanwhile, paleo-climate modeling outputs from the National Center for Atmospheric Research Community Climate System Model 4.0 show similar multidecadal variations in the monsoon precipitation. One of those variations at the frequency of 40–50 years per cycle is examined in this study. Major results show that this variation is a product of the processes in that the meridional gradient of the atmospheric enthalpy is strengthened by radiation loss in the high-latitude and polar region. Driven …
Combined Analysis Of Soil Moisture Measurements
From Roving And Fixed Cosmic Ray Neutron Probes
For Multiscale Real-Time Monitoring,
2015
University of Nebraska-Lincoln
Combined Analysis Of Soil Moisture Measurements From Roving And Fixed Cosmic Ray Neutron Probes For Multiscale Real-Time Monitoring, Trenton E. Franz, Tiejun Wang, William Avery, Catherine E. Finkenbiner, Luca Brocca
School of Natural Resources: Faculty Publications
Soil moisture partly controls land-atmosphere mass and energy exchanges and ecohydrological processes in natural and agricultural systems. Thus, many models and remote sensing products continue to improve their spatiotemporal resolution of soil moisture, with some land surface models reaching 1 km resolution. However, the reliability and accuracy of both modeled and remotely sensed soil moisture require comparison with ground measurements at the appropriate spatiotemporal scales. One promising technique is the cosmic ray neutron probe. Here we further assess the suitability of this technique for real-time monitoring across a large area by combining data from three fixed probes and roving surveys …
Bringing The Passion Back: Using Your Expertise To Gain Experience, Improve Motivation, And Create Real Change In Global Agriculture,
2015
University of Nebraska - Lincoln
Bringing The Passion Back: Using Your Expertise To Gain Experience, Improve Motivation, And Create Real Change In Global Agriculture, J.M.D. Motschenbacher
School of Natural Resources: Faculty Publications
No abstract provided.
Daily Soil Surface Co2 Flux During Non-Flooded Periods In Flood-Irrigated Rice Rotations,
2015
University of Nebraska - Lincoln
Daily Soil Surface Co2 Flux During Non-Flooded Periods In Flood-Irrigated Rice Rotations, J. M. Motschenbacher, K. R. Brye, M. M. Anders, E. E. Gbur, N. A. Slaton, M. A. Evans-White
School of Natural Resources: Faculty Publications
No abstract provided.
Atmospheric Responses To North Atlantic Sst Anomalies In Idealized Experiments. Part I: Northern Hemispheric Circulation,
2015
University of Nebraska-Lincoln
Atmospheric Responses To North Atlantic Sst Anomalies In Idealized Experiments. Part I: Northern Hemispheric Circulation, Michael C. Veres, Qi Hu
School of Natural Resources: Faculty Publications
Idealized model experiments using the NCAR CESM1.0.5 under equinox conditions are designed and performed to address two fundamental questions about the effects of the sea surface temperature (SST) variation associated with the Atlantic multidecadal oscillation (AMO) on circulation and precipitation in North America and Europe: 1) Is the observed relationship between the AMOSST and the warm-season precipitation in North America a statistical coincidence? and 2)Why is the response of negative precipitation anomaly to warm SST in the AMO fairly uniform across most of North America, whereas the positive precipitation anomaly in the cold SST rather spotty? Model experiments are done …
Estimation Of Crop Gross Primary Production (Gpp): Ii. Do Scaledmodis Vegetation Indices Improve Performance?,
2015
Universities Space Research Association
Estimation Of Crop Gross Primary Production (Gpp): Ii. Do Scaledmodis Vegetation Indices Improve Performance?, Qingyuan Zhang, Yen-Ben Cheng, Alexei I. Lyapustin, Yujie Wang, Xiaoyang Zhang, Andrew E. Suyker, Shashi Verma, Yanmin Shuai, Elizabeth M. Middleton
School of Natural Resources: Faculty Publications
Satellite remote sensing estimates of gross primary production (GPP) have routinely been made using spectral vegetation indices (VIs) over the past two decades. The Normalized Difference Vegetation Index(NDVI), the Enhanced Vegetation Index (EVI), the green band Wide Dynamic Range Vegetation Index(WDRVIgreen), and the green band Chlorophyll Index (CIgreen) have been employed to estimate GPP under the assumption that GPP is proportional to the product of VI and photosynthetically active radiation (PAR)(where VI is one of four VIs: NDVI, EVI, WDRVIgreen, or CIgreen). However, the empirical regressions between VI*PAR and GPP measured locally …
An Exploration Of The Moderating Effect Of Motivation On The Relationship Between Work Satisfaction And Utilization Of Virtual Team Effectiveness Attributes: A Mixed Methods Study,
2015
University of Nebraska at Lincoln
An Exploration Of The Moderating Effect Of Motivation On The Relationship Between Work Satisfaction And Utilization Of Virtual Team Effectiveness Attributes: A Mixed Methods Study, F. C. Day, Mark E. Burbach
School of Natural Resources: Faculty Publications
No abstract provided.
Cars And Karst: Investigating The National Corvette Museum Sinkhole,
2015
Western Kentucky University
Cars And Karst: Investigating The National Corvette Museum Sinkhole, Jason S. Polk, Leslie North, Ric Federico, Brian Ham, Dan Nedvidek, Kegan Mcclanahan, Pat Kambesis, Michael Marasa
Earth, Environmental, and Atmospheric Sciences Faculty Publications
On February 12th, 2014, a sinkhole occurred at the National Corvette Museum in Bowling Green, Kentucky. The collapse happened inside part of the building known as the Skydome and eight Corvettes on display were lost into the void that opened in the concrete floor. In this region of Kentucky, known as the Pennyroyal sinkhole plain, subsidence and cover collapse sinkholes are commonly found throughout the landscape. This iconic karst region in the United States is also home to Mammoth Cave, the longest cave in the world, and thousands of other caves and karst features. Investigation of the sinkhole collapse began …
A Unifying Gravity Framework For Dispersal,
2015
University of Nebraska - Lincoln
A Unifying Gravity Framework For Dispersal, E. Jongejans, O. Skarpaas, M. J. Ferrari Et Al.
School of Natural Resources: Faculty Publications
No abstract provided.
2015 Academic Program Review School Of Natural Resources
University Of Nebraska–Lincoln,
2015
University of Nebraska - Lincoln
2015 Academic Program Review School Of Natural Resources University Of Nebraska–Lincoln
School of Natural Resources: Documents and Reviews
No abstract provided.
Phytoremediation Of Metal Contamination Using Salix (Willows),
2015
University of Denver
Phytoremediation Of Metal Contamination Using Salix (Willows), Gordon J. Kersten
Electronic Theses and Dissertations
Abandoned hardrock mines and the resulting Acid Mine Drainage (AMD) are a source of vast, environmental degradation that are toxic threats to plants, animals, and humans. Cadmium (Cd) and lead (Pb) are metal contaminants often found in AMD. In my mine outwash water samples, cadmium and lead concentrations were 19 and 160 times greater than concentrations in control waterways, and 300 and 40 times greater than EPA Aquatic Life Use water quality standards, respectively. I tested the phytoremediation characteristics of three montane willows native to the Rocky Mountains: Salix drummondiana, S. monticola, and S. planifolia. I tested …
Evaluating An Unconfined Aquifer By Analysis Of Age-Dating
Tracers In Stream Water,
2015
University of Utah
Evaluating An Unconfined Aquifer By Analysis Of Age-Dating Tracers In Stream Water, D. K. Solomon, T. E. Gilmore, B. Kimball, D. P. Genereux
School of Natural Resources: Faculty Publications
The mean transit time (MTT) is a fundamental property of a groundwater flow system that is strongly related to the ratio of recharge rate to storage volume. However, obtaining samples for estimating the MTT using environmental tracers is problematic as flow-weighted samples over the full spectrum of transit times are needed. Samples collected fromthe base flow of a gaining stream in the North Carolina Coastal Plain (West Bear Creek) that were corrected for exchange with the atmosphere yielded environmental tracer concentrations (SF6 and CFC-11) very similar to flow-weighted values from nine or ten streambed piezometers that directly sampled groundwater …
Application Of Remote Sensing For Quantifying And Mapping Surface Energy Fluxes In South Central Nebraska: Analyses With Respect To Field Measurements,
2015
University of Nebraska-Lincoln
Application Of Remote Sensing For Quantifying And Mapping Surface Energy Fluxes In South Central Nebraska: Analyses With Respect To Field Measurements, Vivek Sharma, Suat Irmak, Ayse Kilic, Denis Mutibwa
School of Natural Resources: Faculty Publications
Large-scale quantification of crop evapotranspiration (ETc) from various vegetation surfaces can aid in planning, managing, and allocating water resources. Field measurement of surface energy fluxes, including ETc, remains (and should remain) a crucial process for calibration and validation of satellite/remote sensing-based methods, which can provide important supporting information for water balance assessments and for analyzing the spatial distribution of energy fluxes on large scales. The Surface Energy Balance System (SEBS) was evaluated in estimating surface energy fluxes in south central Nebraska using Landsat imagery and meteorological data. SEBS-estimated surface energy fluxes were compared to Bowen Ratio Energy Balance System (BREBS) …
