Physical Sciences and Mathematics Commons^™

Estimation Of Chlorophyll-A Concentration In Case Ii Waters Using Modis And Meris Data—Successes And Challenges, Wesley Moses, Anatoly Gitelson, Sergey Berdnikov, Vasiliy Povazhnyi

Papers in Natural Resources

We present and discuss here the results of our work using MODIS (moderate resolution imaging spectroradiometer) and MERIS (medium resolution imaging spectrometer) satellite data to estimate the concentration of chlorophyll-a (chl-a) in reservoirs of the Dnieper River and the Sea of Azov, which are typical case II waters, i.e., turbid and productive. Our objective was to test the potential of satellite remote sensing as a tool for near-real-time monitoring of chl-a distribution in these water bodies. We tested the performance of a recently developed three-band model, and its special case, a two-band model, which use the reflectance at red and …

Corrections To “Satellite Estimation Of Chlorophyll-A Concentration Using The Red And Nir Bands Of Meris—The Azov Sea Case Study”, Wesley J. Moses, Anatoly A. Gitelson, Sergey Berdnikov, Vasiliy Povazhnyy

Papers in Natural Resources

We correct here some errors that appear in our paper: W.J. Moses, A.A. Gitelson, S. Berdnikov, and V. Povazhnyy, “Satellite estimation of chlorophyll-a concentration using the red and NIR bands of MERIS—The Azov Sea case study,” IEEE Geoscience and Remote Sensing Letters, volume 6, number 4, pp. 845–849, October 2009.

Satellite Estimation Of Chlorophyll-A Concentration Using The Red And Nir Bands Of Meris—The Azov Sea Case Study, Wesley J. Moses, Anatoly A. Gitelson, Sergey Berdnikov, Vasiliy Povazhnyy

Papers in Natural Resources

We present here the results of calibrating and validating a three-band model and, its special case, a two-band model, which use MEdium Resolution Imaging Spectrometer (MERIS) reflectances in the red and near-infrared spectral regions for estimating chlorophyll-a (chl-a) concentration in inland, estuarine, and coastal turbid productive waters. During four data collection campaigns in 2008 and one campaign in 2009 in the Taganrog Bay and the Azov Sea, Russia, water samples were collected, and concentrations of chl-a and total suspended solids were measured in the laboratory. The data collected in 2008 were used for model calibration, and the …

Wilderness Serendipity: Planning And Assessing Learning During An Experiential Field Course, Larkin A. Powell, Andrew J. Tyre, Scott E. Hygnstrom, David A. Wedin, P. R. Hanson, Mark S. Kuzila, James B. Swinehart

Papers in Natural Resources

Experiential learning opportunities promote skill in problem-solving and critical thinking, but they require unique assessment methods because traditional approaches are difficult to implement in the field. We have conducted a study tour course involving a canoe trip in a wilderness area in northern Minnesota since 2004. Here, we describe how we developed our course's learning experiences, ensured the learning experiences materialized, and assessed the student learning objectives. Proper planning can result in valuable, spontaneous learning experiences. We used a student journal, field-based quiz, and participation grade to effectively assess the breadth of student learning that was inherent in our course. …

Retrieval Of Foliar Information About Plant Pigment Systems From High Resolution Spectroscopy, Susan L. Ustin, Anatoly A. Gitelson, Stéphane Jacquemoud, Michael Schaepman, Gregory P. Asner, John A. Gamon, Pablo Zarco-Tejada

Papers in Natural Resources

Life on Earth depends on photosynthesis. Photosynthetic systems evolved early in Earth history and have been stable for 2.5 billion years, providing prima facie evidence for the significance of pigments in plant functions. Photosynthetic pigments fill multiple roles from increasing the range of energy captured for photosynthesis to protective functions. Given the importance of pigments to leaf functioning, greater effort is needed to determine whether individual pigments can be identified and quantified in vivo using high fidelity spectroscopy. We review recent advances in detecting plant pigments at the leaf level and discuss successes and reasons why challenges remain for robust …

Photosynthetic Performance Of Invasive Pinus Ponderosa And Juniperus Virginiana Seedlings Under Gradual Soil Water Depletion, Saadia Bihmidine, N. M. Bryan, K. R. Payne, M. R. Parde, Jane A. Okalebo, Sharon E. Cooperstein, Tala Awada

Papers in Natural Resources

Changes in climate, land management and fire regime have contributed to woody species expansion into grasslands and savannas worldwide. In the USA, Pinus ponderosa P. & C. Lawson and Juniperus virginiana L. are expanding into semiarid grasslands of Nebraska and other regions of the Great Plains. We examined P. ponderosa and J. virginiana seedling response to soil water content, one of the most important limiting factors in semiarid grasslands, to provide insight into their success in the region. Photosynthesis, stomatal conductance, maximum photochemical efficiency of PSII, maximum carboxylation velocity, maximum rate of electron transport, stomatal limitation to photosynthesis, water potential, …

Quality Control Of Soil Water Data In Applied Climate, Jinshing You, Kenneth Hubbard, Rezaul Mamood, Venkataramana Sridhar, Dennis Todey

Papers in Natural Resources

Abstract: Soil moisture is a key state variable from both climate and hydrologic cycle assessment perspectives. Recently, automated measurements of soil moisture with sensors deployed at sites in a real-time monitoring network have provided valuable new data to monitor the soil water resource. However, to assure the quality of the data, quality control QC tools are needed. Earlier studies left little literature on the QC of soil water data as measurements were generally not part of a network that routinely collected measurements. This paper presents a systematic QC analysis and methodology to evaluate the performance of candidate QC techniques using …

Tree Canopy Effect On Grass And Grass/Legume Mixtures In Eastern Nebraska, Michael El. L. Perry, Walter H. Schacht, Gregory A. Ruark, James R. Brandle

Papers in Natural Resources

A study to determine the feasibility of producing forage for grazing livestock under trees was conducted as a step toward evaluating the potential for silvopasture systems in the northern and central Great Plains. The effects of overstory leaf area index (LAI), percentage understory light transmittance (LT), and soil moisture (SM) on yield and crude protein (CP) of big bluestem [Andropogon gerardii Vitman; (BB)], smooth bromegrass [ Bromus inermis Leyss.; (SB)], and mixtures with birdsfoot trefoil [ Lotus corniculatus L.; (BFT)] were examined. The study was conducted in both Scotch pine (Pinus sylvestris L.) and green ash (Fraxinus …

Avian Foraging Patterns In Crop Field Edges Adjacent To Woody Habitat, Heidi L. Puckett, James R. Brandle, Ron J. Johnson, Erin E. Blankenship

Papers in Natural Resources

As natural predators of pest insects, woodland birds provide biological pest suppression in crop fields adjacent to woody edges. Although many birds using these habitats forage widely, earlier studies have found that most foraging activity occurs within 50 m of the woody edge. The goals of this study were to determine the primary area of use, or functional edge, for birds foraging in crop fields adjacent to woody edges, and to evaluate their foraging distance patterns. During the summers of 2005 and 2006, avian foraging behavior was observed at 12 research sites in east central Nebraska that contained either a …

Phylogeography Of The Rufous-Naped Wren (Campylorhynchus Rufinucha): Speciation And Hybridization In Mesoamerica, Hernan Vazquez-Miranda, Adolfo G. Navarro-Siguenza, Kevin E. Omland

Papers in Natural Resources

The Rufous-naped Wren (Campylorhynchus rufinucha) is a sedentary, morphologically variable species distributed in the dry forests of Mesoamerica. It ranges from Colima, Mexico, south to Costa Rica along the Pacific slope, with a disjunct population in central Veracruz. Populations of two forms on the Pacific slope intergrade in Chiapas, Mexico, apparently as a result of secondary contact. We sequenced a mitochondrial DNA (mtDNA) gene to explore phylogeographic patterns and hybridization. We found three divergent lineages, two geographically spanning the Isthmus of Tehuantepec and a disjunct Veracruz population. Analyses of molecular variation and statistics are consistent with genetically distinct …

A Comparison Between Above-Water Surface And Subsurface Spectral Reflectances Collected Over Inland Waters, Asif M. Bhatti, Donald Rundquist, John Schalles, Luis Ramirez, Seigo Nasu

Papers in Natural Resources

The objective of the research was to undertake a quantitative comparison of spectral-reflectance measurements made slightly above the surface of water bodies with the measurements made slightly below the surface. The study is focused on three rivers; two in Georgia, USA and one in Japan. As expected, the differences in reflectance are not constant and vary with the wavelength. The contribution of surface-reflection effects to the surface reflectance measured slightly above the water is both pronounced and highly variable, but although they do alter the magnitude of the upwelling signal, they do not change the general shape of the spectral …

Evapotranspiration Of Irrigated And Rainfed Maize–Soybean Cropping Systems, Andrew E. Suyker, Shashi Verma

Papers in Natural Resources

We have been making year-round measurements of mass and energy exchange in three cropping systems: (a) irrigated continuous maize, (b) irrigated maize–soybean rotation, and (c) rainfed maize–soybean rotation in eastern Nebraska since 2001. In this paper, we present results on evapotranspiration (ET) of these crops for the first 5 years of our study. Growing season ET in the irrigated and rainfed maize averaged 548 and 482 mm, respectively. In irrigated and rainfed soybean, the average growing season ET was 452 and 431 mm, respectively. On average, the maize ET was higher than the soybean ET by 18% for irrigated crops …

A Modified Advection-Aridity Model Of Evapotranspiration, Jozsef Szilagyi, Michael T. Hobbins, Janos Jozsa

Papers in Natural Resources

No abstract provided.

Lithobates Catesbeianus (American Bullfrog) Predation On Cliff Swallows, Mary Bomberger Brown, Charles R. Brown

Papers in Natural Resources

During a 25-year study of Cliff Swallows (Petrochelidon pyrrhonota) in southwestern Nebraska, we observed Lithobates catesbeianus prey on, or attempt to prey on, Cliff Swallows. As we were mist-netting Cliff Swallows at a 10-nest colony on 7 July 1998, a L. catesbeianus attempted to eat a Cliff Swallow that was caught in the net.

Characterizing The Seasonal Dynamics Of Plant Community Photosynthesis Across A Range Of Vegetation Types, Lianhong Gu, Wilfred M. Post, Dennis D. Baldocchi, T. Andrew Black, Andrew E. Suyker, Shashi Verma, Timo Vesala, Steve C. Wofsy

Papers in Natural Resources

The seasonal cycle of plant community photosynthesis is one of the most important biotic oscillations to mankind. This study built upon previous efforts to develop a comprehensive framework to studying this cycle systematically with eddy covariance flux measurements. We proposed a new function to represent the cycle and generalized a set of phenological indices to quantify its dynamic characteristics. We suggest that the seasonal variation of plant community photosynthesis generally consists of five distinctive phases in sequence each of which results from the interaction between the inherent biological and ecological processes and the progression of climatic conditions and reflects the …

Analytical Solution Of The Coupled 2-D Turbulent Heat And Vapor Transport Equations And The Complementary Relationship Of Evaporation, Jozsef Szilagyi, Janos Jozsa

Papers in Natural Resources

No abstract provided.

Estimating Spatially Distributed Monthly Evapotranspiration Rates By Linear Transformations Of Modis Daytime Land Surface Temperature Data, J. Szilagyi, J. Jozsa

Papers in Natural Resources

No abstract provided.

Differential Soil Respiration Responses To Changing Hydrologic Regimes, Vincent J. Pacific, Brian L. Mcglynn, Diego Andrés Riveros-Iregui, Howard E. Epstein, Daniel J. Welsch

Papers in Natural Resources

Soil respiration is tightly coupled to the hydrologic cycle (i.e., snowmelt and precipitation timing and magnitude). We examined riparian and hillslope soil respiration across a wet (2005) and a dry (2006) growing season in a subalpine catchment. When comparing the riparian zones, cumulative CO₂ efflux was 33% higher, and peak efflux occurred 17 days earlier during the dry growing season. In contrast, cumulative efflux in the hillslopes was 8% lower, and peak efflux occurred 10 days earlier during the drier growing season. Our results demonstrate that soil respiration was more sensitive to drier growing season conditions in wet (riparian) …

Integrating Remote Sensing And Geographic Information Systems, James W. Merchant, Sunil Narumalani

Papers in Natural Resources

Remote sensing and geographic information systems (GIS) comprise the two major components of geographic information science (GISci), an overarching field of endeavor that also encompasses global positioning systems (GPS) technology, geodesy and traditional cartography (Goodchild 1992, Estes and Star 1993, Hepner et al. 2005). Although remote sensing and GIS developed quasi-independently, the synergism between them has become increasingly apparent (Aronoff 2005). Today, GIS software almost always includes tools for display and analysis of images, and image processing software commonly contains options for analyzing ‘ancillary’ geospatial data (Faust 1998). The significant progress made in ‘integration’ of remote sensing and GIS has …

Estimation Of Chlorophyll-A Concentration In Case Ii Waters Using Modis And Meris Data—Successes And Challenges, Wesley J. Moses, Anatoly A. Gitelson, V. Povazhnyy

Papers in Natural Resources

We present and discuss here the results of our work using MODIS (moderate resolution imaging spectroradiometer) and MERIS (medium resolution imaging spectrometer) satellite data to estimate the concentration of chlorophyll-a (chl-a) in reservoirs of the Dnieper River and the Sea of Azov, which are typical case II waters, i.e., turbid and productive. Our objective was to test the potential of satellite remote sensing as a tool for near-real-time monitoring of chl-a distribution in these water bodies. We tested the performance of a recently developed three-band model, and its special case, a two-band model, which use the …

Corrigendum To “Incorporation Of Crop Phenology In Simple Biosphere Model (Sibcrop) To Improve Land-Atmosphere Carbon Exchanges From Croplands” Published In Biogeosciences, 6, 969–986, 2009, Erandathie Lokupitiya, S. Denning, K. Paustian, I. Baker, K. Schaefer, Shashi B. Verma, T. Meyers, C. J. Bernacchi, Andrew E. Suyker, M. L. Fischer

Papers in Natural Resources

In the above mentioned manuscript a mistake in Fig. 11 occured. The corrected version of the figure is as follows.

A Century Of Climate Change For Fairbanks, Alaska, Gerd Wendler, Martha Shulski

Papers in Natural Resources

Climatological observations are available for Fairbanks, Interior Alaska, for up to 100 years. This is a unique data set for Alaska, insofar as it is of relatively high quality and without major breaks. Applying the best linear fit, we conclude that the mean annual temperature rose from -3.6°C to -2.2°C over the century, an increase of 1.4°C (compared to 0.8°C worldwide). This comparison clearly demonstrates the well-known amplification or temperature change for the polar regions. The observed temperature increase is neither uniform over the time period nor uniform throughout the course of a year. The winter, spring, and summer seasons …

Lichen Recovery Following Heavy Grazing By Reindeer Delayed By Climate Warming, David R. Klein, Martha Shulski

Papers in Natural Resources

Introduced reindeer, Rangifer tarandus, over exploited lichen-rich plant communities on St. Matthew Island in the Bering Sea. A die-off of the reindeer followed, exacerbated by extreme weather in 1964, resulting in extirpation of the reindeer. A similar pattern of removal of lichens as major components of plant communities has occurred following introductions of reindeer to other islands at high latitudes. By 1985, two decades following die-off of the reindeer, total lichen biomass was only 6% of that in similar plant communities on adjacent Hall Island, not reached by the reindeer. By 2005, 41 y after the reindeer die-off, lichen …

A Phylogenetic Supertree Of The Fowls (Galloanserae, Aves), Soo Hyumg Eo, Olaf R.P. Bininda-Emonds, John P. Carroll

Papers in Natural Resources

The fowls (Anseriformes and Galliformes) comprise one of the major lineages of birds and occupy almost all biogeographical regions of the world. The group contains the most economically important of all bird species, each with a long history of domestication, and is an ideal model for studying ecological and evolutionary patterns. Yet, despite the relatively large amount of systematic attention fowls have attracted because of their socio-economic and biological importance, the species-level relationships within this clade remain controversial. Here we used the supertree method matrix representation with parsimony to generate a robust estimate of species-level relationships of fowls. The supertree …

2009 Interior Least Tern And Piping Plover Monitoring, Research, Management, And Outreach Report For The Lower Platte River, Nebraska, Mary Bomberger Brown, Joel G. Jorgensen

Papers in Natural Resources

This document reports on our monitoring, research, management, and outreach activities during the past 12 months (2009). We prepared it to inform our partners, cooperating agencies, funding sources, and other interested parties of our activities and to provide a preliminary summary of our results.

The Tern and Plover Conservation Partnership (TPCP), based at the University of Nebraska–School of Natural Resources, and the Nongame Bird Program (NBP), based at the Nebraska Game and Parks Commission (NGPC) work cooperatively on Interior Least Tern and Piping Plover monitoring, research, management, and education-outreach activities. While the proximate focus of our work is the Lower …

Comment On ‘‘Power Law Catchment-Scale Recessions Arising From Heterogeneous Linear Small-Scale Dynamics’’ By C. J. Harman, M. Sivapalan, And P. Kumar, Jozsef Szilagyi

Papers in Natural Resources

It is demonstrated that a near-linear subsurface runoff response from a short and relatively steep slope segment and a nonlinear response at the watershed scale may primarily arise from geometry rather than from an assumed linear nature of the subsurface runoff response from the hillslope, as Harman et al. [2009] employed for the Panola Mountain Research (PMR) catchment in Georgia. The authors caution in their paper that hydraulic theory (exemplified by the study of Brutsaert and Nieber [1977]) cannot generally account for the heterogeneity in the watershed scale and therefore should be used with certain reservation when employing it for …

Remote Sensing Of Cropland Agriculture, M. Duane Nellis, Kevin P. Price, Donald Rundquist

Papers in Natural Resources

Remote sensing has long been used in monitoring and analyzing agricultural activities. Well prior to the first coining of the term ‘remote sensing’ in 1958 by Eveyln Pruitt of the U.S. Office of Naval Research (Estes and Jensen 1998), scientists were using aerial photography to complete soil and crop surveys associated with agricultural areas in the United States and other parts of the world (Goodman 1959). Most of such work in the 1930s involved general crop inventories by the U.S. Department of Agriculture and soil survey mapping as part of the work of the then U.S. Soil Conservation Service. With …

A Bio-Optical Algorithm For The Remote Estimation Of The Chlorophyll-A Concentration In Case 2 Waters, Anatoly A. Gitelson, Daniela Gurlin, Wesley Moses, Tadd Barrow

Papers in Natural Resources

The objective of this work was to test the performance of a recently developed three-band model and its special case, a two-band model, for the remote estimation of the chlorophyll-a (chl-a) concentration in turbid productive case 2 waters. We specifically focused on (a) determining the ability of the models to estimate chl-a < 20 mg m⁻³, typical for coastal and estuarine waters, and (b) assessing the potential of MODIS and MERIS to estimate chl-a concentrations in turbid productive waters, using red and near-infrared (NIR) bands. Reflectance spectra and water samples were collected in 89 stations over lakes in …

Variability Of Anaerobic Animal Waste Lagoon Delta15N Source Signatures, Sadayappan Mariappan, Mary Exner Spalding, Glen E. Martin, Roy F. Spalding

Papers in Natural Resources

High ammonium-N concentrations derived from animal wastes stored and partially treated in earthen anaerobic lagoons at confined feeding facilities can seep to groundwater. δ¹⁵N-NH₄⁺ values from +2.0 to +59.1‰ in 13 lagoons complicate identification of lagoon seepage as well as land-applied lagoon effluent in ground and surface waters. The spectrum of δ¹⁵N values requires site-specific isotope characterization of the potential source. Feed and fresh manure and urine δ¹⁵N values indicate that most N isotopic fractionation occurs after excretion. Lagoon management clearly affects enrichment. δ¹⁵N-total Kjeldahl N (TKN) and δ^{15 …}

Non-Destructive Estimation Of Anthocyanins And Chlorophylls In Anthocyanic Leaves, Anatoly A. Gitelson, Olga B. Chivkunova, Mark N. Merzlyak

Papers in Natural Resources

The anthocyanin and chlorophyll contents in leaves provide valuable information about the physiological status of plants. Thus, there is a need for accurate, efficient, and practical methodologies to estimate these biochemical parameters of vegetation. In this study, we tested the performance and accuracy of several nondestructive, reflectance-based techniques for estimating anthocyanin and chlorophyll contents in leaves of four unrelated species, European hazel ( Corylus avellana ), Siberian dogwood ( Cornus alba = Swida alba ), Norway maple ( Acer platanoides ), and Virginia creeper ( Parthenocissus quinquefolia ), with widely variable pigment content and composition. An anthocyanin reflectance index, which …