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Papers in Natural Resources

2003

Articles 1 - 30 of 33

Full-Text Articles in Physical Sciences and Mathematics

Lewis And Clark And The Geology Of Nebraska And Parts Of Adjacent States, Robert F. Diffendal, Anne P. Diffendal Dec 2003

Lewis And Clark And The Geology Of Nebraska And Parts Of Adjacent States, Robert F. Diffendal, Anne P. Diffendal

Papers in Natural Resources

Meriwether Lewis and William Clark undertook their journey with the Corps of Discovery in 1804–1806 in order to explore the area that the United States had purchased from France in 1803. Then known as Louisiana, this region included almost everything west of the Mississippi to the continental divide (illustrated below). In order to find the best route across the continent, President Thomas Jefferson charged Lewis to follow the Missouri River to its headwaters and then locate rivers flowing down the west side of the Rocky Mountains to the Columbia River and into the Pacific Ocean. Jefferson's written instructions further specified …

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In-Field Labeling Of Western Corn Rootworm Adults (Coleoptera: Chrysomelidae) With Rubidium, Timothy M. Nowatzki, Bradley Niimi, Kelli J. Warren, Sean Putnam, Lance J. Meinke, David C. Gosselin, F. Edwin Harvey, Thomas E. Hunt, Blair Siegfried Dec 2003

In-Field Labeling Of Western Corn Rootworm Adults (Coleoptera: Chrysomelidae) With Rubidium, Timothy M. Nowatzki, Bradley Niimi, Kelli J. Warren, Sean Putnam, Lance J. Meinke, David C. Gosselin, F. Edwin Harvey, Thomas E. Hunt, Blair Siegfried

Papers in Natural Resources

Field and laboratory studies were conducted in 2000 and 2001 to determine the feasibility of mass marking western corn rootworm adults, Diabrotica virgifera virgifera LeConte, with RbCl in the field. Results showed that application of rubidium (Rb) in solution to both the soil (1 g Rb/plant) and whorl (1 g Rb/plant) of corn plants was optimal for labeling western corn rootworm adults during larval development. Development of larvae on Rb-enriched corn with this technique did not significantly influence adult dry weight or survival. Rb was also highly mobile in the plant. Application of Rb to both the soil and the …

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Lewis And Clark And The Geology Of The Great Plains, Robert F. Diffendal, Anne P. Diffendal Dec 2003

Lewis And Clark And The Geology Of The Great Plains, Robert F. Diffendal, Anne P. Diffendal

Papers in Natural Resources

Meriwether Lewis and William Clark undertook their journey with the Corps of Discovery in 1804-1806 in order to explore the area that the United States had purchased from France in 1803. Then known as Louisiana, this region included almost everything west of the Mississippi to the continental divide (fig. 1). In order to find the best route across the continent, President Thomas Jefferson charged Lewis with following the Missouri River to its headwaters and then locating rivers flowing down the west side of the Rocky Mountains to the Columbia River and into the Pacific Ocean. Jefferson's written instructions further specified …

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Avhrr-Based Spectral Vegetation Index For Quantitative Assessment Of Vegetation State And Productivity: Calibration And Validation, Felix Kogan, Anatoly A. Gitelson, Edige Zakarin, Lev Spivak, Lubov Lebed Aug 2003

Avhrr-Based Spectral Vegetation Index For Quantitative Assessment Of Vegetation State And Productivity: Calibration And Validation, Felix Kogan, Anatoly A. Gitelson, Edige Zakarin, Lev Spivak, Lubov Lebed

Papers in Natural Resources

The goal of the work was to estimate, quantitatively, vegetation state and productivity using AVHRR-based Vegetation Condition Index (VCI). The VCI algorithm includes application of post-launch calibration to visible channels, calculation of NDVI from channels’ reflectance, removal of high-frequency noise from NDVI’s annual time series, stratification of ecosystem resources, and separation of ecosystem and weather components in the NDVI value. The weather component was calculated by normalizing the NDVI to the difference of the extreme NDVI fluctuations (maximum and minimum), derived from multi-year data for each week and land pixel. The VCI was compared with wheat density measured in Kazakhstan. …

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Ecomorphology Of Bats: Comparative And Experimental Approaches Relating Structural Design To Ecology, Sharon M. Swartz, Patricia W. Freeman, Elizabeth F. Stockwell May 2003

Ecomorphology Of Bats: Comparative And Experimental Approaches Relating Structural Design To Ecology, Sharon M. Swartz, Patricia W. Freeman, Elizabeth F. Stockwell

Papers in Natural Resources

The past several decades have seen the beginning of integration of discoveries in the ecology and morphology of bats into an ecomorphological whole that promises to be greater than the sum of its parts. However, achieving this integration is challenging. Each of the elements of this interdisciplinary field is, in itself, avast and complex subject. This book is a testament to the breadth and depth of ecological studies of bats. Morphological studies now extend be- yond descriptive anatomy in both outlook and method, and incorporate, for example, aspects of genetics, physiology, solid and fluid mechanics, and developmental biology. There is …

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Parasite Remains In Archaeological Sites, Françoise Bouchet, Niéde Guidon, Katharina Dittmar, Stephanie Harter, Luiz F. Ferreira, Sérgio A.M. Chaves, Karl J. Reinhard, Adauto Araújo Feb 2003

Parasite Remains In Archaeological Sites, Françoise Bouchet, Niéde Guidon, Katharina Dittmar, Stephanie Harter, Luiz F. Ferreira, Sérgio A.M. Chaves, Karl J. Reinhard, Adauto Araújo

Papers in Natural Resources

Organic remains can be found in many different environments. They are the most significant source for paleoparasitological studies as well as for other paleoecological reconstruction. Preserved paleoparasitological remains are found from the driest to the moistest conditions. They help us to understand past and present diseases and therefore contribute to understanding the evolution of present human sociality, biology, and behavior. In this paper, the scope of the surviving evidence will be briefly surveyed, and the great variety of ways it has been preserved in different environments will be discussed. This is done to develop to the most appropriated techniques to …

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A Case Of Megacolon In Rio Grande Valley As A Possible Case Of Chagas Disease, Karl J. Reinhard, Thomas M. Fink, Jack Skiles Feb 2003

A Case Of Megacolon In Rio Grande Valley As A Possible Case Of Chagas Disease, Karl J. Reinhard, Thomas M. Fink, Jack Skiles

Papers in Natural Resources

We have been searching for evidence of Chagas disease in mummified human remains. Specifically, we have looked for evidence of alteration of intestinal or fecal morphology consistent with megacolon, a condition associated with Chagas disease. One prehistoric individual recovered from the Chihuahuan Desert near the Rio Grande exhibits such pathology. We present documentation of this case. We are certain that this individual presents a profoundly altered large intestinal tract and we suggest that further research should focus on confirmation of a diagnosis of Chagas disease. We propose that the prehistoric activity and dietary patterns in Chihuahua Desert hunter/gatherers promoted the …

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Paleopharmacology And Pollen: Theory, Method, And Application, Sérgio A.M. Chaves, Karl J. Reinhard Feb 2003

Paleopharmacology And Pollen: Theory, Method, And Application, Sérgio A.M. Chaves, Karl J. Reinhard

Papers in Natural Resources

Parasitism was a universal human condition. Because of this, people developed herbal medicines to treat parasites as part of their pharmacopoeias. We propose that it is possible to recover evidence of medicinal plants from archaeological sites and link their use to specific health conditions. This is a multidisciplinary approach that must involve at least paleoethnobotanists, archaeoparasitologists, paleopathologists, and pharmacologists.

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Pathoecology Of Chiribaya Parasitism, Elizabeth Martinson, Karl J. Reinhard, Jane E. Buikstra, Katharina Dittmar De La Cruz Feb 2003

Pathoecology Of Chiribaya Parasitism, Elizabeth Martinson, Karl J. Reinhard, Jane E. Buikstra, Katharina Dittmar De La Cruz

Papers in Natural Resources

The excavations of Chiribaya culture sites in the Osmore drainage of southern Peru focused on the recovery of information about prehistoric disease, including parasitism. The archaeologists excavated human, dog, guinea pig, and llama mummies. These mummies were analyzed for internal and external parasites. The results of the analysis and reconstruction of prehistoric life from the excavations allows us to interpret the pathoecology of the Chiribaya culture.

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Diagnosing Ancient Diphyllobothriasis From Chinchorro Mummies, Karl J. Reinhard, Otto Urban Feb 2003

Diagnosing Ancient Diphyllobothriasis From Chinchorro Mummies, Karl J. Reinhard, Otto Urban

Papers in Natural Resources

Diphyllobothrium pacificum has been reported as a human parasite from coprolites and skeletons in Peru and Chile. Our analysis of Chinchorro mummies from Chile provides the oldest evidence of D. pacificum directly associated with human mummies. These mummies date between 4,000 and 5,000 years ago. The basis for our diagnosis is presented. We find that the size of the eggs in the mummies is smaller than other discoveries of D. pacificum. We suggest that this is due to the peculiar circumstances of preservation of parasite eggs within mummies and the release of immature eggs into the intestinal tract as the …

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Inca Expansion And Parasitism In The Lluta Valley: Preliminary Data, Santoro Calagero, Karl J. Reinhard, Sheila D. Vinton Feb 2003

Inca Expansion And Parasitism In The Lluta Valley: Preliminary Data, Santoro Calagero, Karl J. Reinhard, Sheila D. Vinton

Papers in Natural Resources

Assessing the impact of cultural change on parasitism has been a central goal in archaeoparasitology. The influence of civilization and the development of empires on parasitism has not been evaluated. Presented here is a preliminary analysis of the change in human parasitism associated with the Inca conquest of the Lluta Valley in Northern Chile. Changes in parasite prevalence are described. It can be seen that the change in life imposed on the inhabitants of the Lluta Valley by the Incas caused an increase in parasitism.

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Louse Infestation Of The Chiribaya Culture, Southern Peru: Variation In Prevalence By Age And Sex, Karl J. Reinhard, Jane E. Buikstra Feb 2003

Louse Infestation Of The Chiribaya Culture, Southern Peru: Variation In Prevalence By Age And Sex, Karl J. Reinhard, Jane E. Buikstra

Papers in Natural Resources

In order to improve the interpretive potential of archaeoparasitology, it is important to demonstrate that the epidemiology of ancient parasites is comparable to that of modern parasites. Once this is demonstrated, then we can be secure that the evidence of ancient parasitism truly reflects the pathoecology of parasitic disease. Presented here is an analysis of the paleoepidemiology of Pediculus humanus infestation from 146 mummies from the Chiribaya culture 1000-1250 AD of Southern Peru. The study demonstrates the modern parasitological axiom that 10% of the population harbors 70% of the parasites holds true for ancient louse infestation. This is the first …

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Enterobius Vermicularis: Ancient Dna From North And South American Human Coprolites, Alena M. Iñiguez, Karl J. Reinhard, Adauto Araújo, Luiz F. Ferreira, Ana Carolina P. Vicente Feb 2003

Enterobius Vermicularis: Ancient Dna From North And South American Human Coprolites, Alena M. Iñiguez, Karl J. Reinhard, Adauto Araújo, Luiz F. Ferreira, Ana Carolina P. Vicente

Papers in Natural Resources

A molecular paleoparasitological diagnostic approach was developed for Enterobius vermicularis. Ancient DNA was extracted from 27 coprolites from archaeological sites in Chile and USA. Enzymatic amplification of human mtDNA sequences confirmed the human origin. We designed primers specific to the E. vermicularis 5S ribosomal RNA spacer region and they allowed reproducible polymerase chain reaction identification of ancient material. We suggested that the paleoparasitological microscopic identification could accompany molecular diagnosis, which also opens the possibility of sequence analysis to understand parasite-host evolution.

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Parasitism, The Diversity Of Life, And Paleoparasitology, Adauto Araújo, Ana M. Jansen, Françoise Bouchet, Karl J. Reinhard, Luiz F. Ferreira Feb 2003

Parasitism, The Diversity Of Life, And Paleoparasitology, Adauto Araújo, Ana M. Jansen, Françoise Bouchet, Karl J. Reinhard, Luiz F. Ferreira

Papers in Natural Resources

The parasite-host-environment system is dynamic, with several points of equilibrium. This makes it difficult to trace the thresholds between benefit and damage, and therefore, the definitions of commensalism, mutualism, and symbiosis become worthless. Therefore, the same concept of parasitism may encompass commensalism, mutualism, and symbiosis. Parasitism is essential for life. Life emerged as a consequence of parasitism at the molecular level, and intracellular parasitism created evolutive events that allowed species to diversify. An ecological and evolutive approach to the study of parasitism is presented here. Studies of the origin and evolution of parasitism have new perspectives with the development of …

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Techniques Of Dna-Studies On Prehispanic Ectoparasites (Pulex Sp., Pulicidae, Siphonaptera) From Animal Mummies Of The Chiribaya Culture, Southern Peru, Katharina Dittmar, U. Mammat, M. Whiting, Sonia Guillén, Karl J. Reinhard, T Goldmann Feb 2003

Techniques Of Dna-Studies On Prehispanic Ectoparasites (Pulex Sp., Pulicidae, Siphonaptera) From Animal Mummies Of The Chiribaya Culture, Southern Peru, Katharina Dittmar, U. Mammat, M. Whiting, Sonia Guillén, Karl J. Reinhard, T Goldmann

Papers in Natural Resources

During a paleoparasitological survey of several animal mummies (Cavia aperea f. porcellus and Canis familiaris) from Chiribaya Baja, an archaeological site in Southern Peru, an unexpected find was made. In the well preserved fur, large numbers of mummified fleas (Pulex simulans/irritans) that parasitized the animals during life were encountered. Due to the relative recent event of the host mummification and the outstanding preservation of the fleas, an attempt for the retrieval of DNA was made. A DNA extraction and sequencing protocol for archaeological ectoparasitic remains has been established, taking additional studies for tissue and protein preservation into account. Tissue preservation …

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Novel Technique For Remote Estimation Of Co2 Flux In Maize, Anatoly A. Gitelson, Shashi B. Verma, Andrés Viña, Donald C. Rundquist, Galina P. Keydan, Bryan Leavitt, Timothy J. Arkebauer, George G. Burba, Andrew E. Suyker Jan 2003

Novel Technique For Remote Estimation Of Co2 Flux In Maize, Anatoly A. Gitelson, Shashi B. Verma, Andrés Viña, Donald C. Rundquist, Galina P. Keydan, Bryan Leavitt, Timothy J. Arkebauer, George G. Burba, Andrew E. Suyker

Papers in Natural Resources

There is considerable interest in assessing the magnitude of carbon sources and sinks for agricultural lands, grasslands, and forests. In this paper, we propose a novel technique to remotely assess CO2 fluxes in maize using reflectances (ρ) in two spectral channels either in the green around 550 nm or in the red edge near 700 nm and the NIR (beyond 750 nm). Differences of reciprocal reflectances [(ρGreen)-1 - (ρNIR)-1] and [(ρRedEdge)-1- (ρNIR)-1] accounted for more than 90 percent of the variability in mid-day canopy …

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Ecophysiology Of Seedlings Of Three Mediterranean Pine Species In Contrasting Light Regimes, Tala Awada, Kalliopi Radoglou, Mariangela N. Fotelli, Helen I. A. Constantinidou Jan 2003

Ecophysiology Of Seedlings Of Three Mediterranean Pine Species In Contrasting Light Regimes, Tala Awada, Kalliopi Radoglou, Mariangela N. Fotelli, Helen I. A. Constantinidou

Papers in Natural Resources

Seasonal dynamics of net photosynthesis (Anet) in 2-year-old seedlings of Pinus brutia Ten., Pinus pinea L. and Pinus pinaster Ait. were investigated. Seedlings were grown in the field in two light regimes: sun (ambient light) and shade (25% of photosynthetically active radiation (PAR)). Repeated measures analyses over a 12-month period showed that Anet varied significantly among species and from season to season. Maximum Anet in sun-acclimated seedlings was low in winter (yet remained positive) and peaked during summer. Maximum Anet was observed in June in P. pinea (12 μmol m–2 s–1), …

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Air Temperature Errors Caused By Air Filter And Construction Effects On Hmp45c Temperature Sensors In Weather Stations, K. G. Hubbard, X Lin Jan 2003

Air Temperature Errors Caused By Air Filter And Construction Effects On Hmp45c Temperature Sensors In Weather Stations, K. G. Hubbard, X Lin

Papers in Natural Resources

For non–ventilated air temperature measurements at weather stations, both ambient wind speed and solar radiation are known to affect the magnitude of air temperature measurement errors. The objective of this study is to explore the effect of the sensor’s housing and to quantify any stagnation or conduction errors. The HMP45C temperature and relative humidity sensor with a Gill radiation shield is widely used in remote monitoring sites. The use of a filter in the HMP45C leads to loss of ventilation, while the protrusion of the sensor housing below the Gill shield exposes it to radiation loading and potentially increased conduction …

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Using Earth Science Research Projects To Develop Collaboration Between Scientists At A Research University And K-12 Educators: Insights For Future Efforts, David C. Gosselin, Richard Levy, Ronald J. Bonnstetter Jan 2003

Using Earth Science Research Projects To Develop Collaboration Between Scientists At A Research University And K-12 Educators: Insights For Future Efforts, David C. Gosselin, Richard Levy, Ronald J. Bonnstetter

Papers in Natural Resources

The main goal of this pilot project was to improve collaboration between scientists at a large research university and K-12 educators. By involving scientists and K-12 educators in Earth systems research, we hoped to improve scientists’ awareness of current pedagogy and classroom practices, improve K-12 teachers understanding of actual scientific research and expose each group to the other’s unique culture. Eight research teams (comprising a scientist, pre-service teacher and an in-service teacher) participated in a four-week research experience, attended three half-day workshops, and participated in focus group interviews. This experience reinforced K-12 teachers views that scientific inquiry must be integrated …

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Temporal Variations Of Extreme Precipitation Events In The United States: 1895–2000, Kenneth E. Kunkel, David R. Easterling, Kelly Redmond, Kenneth Hubbard Jan 2003

Temporal Variations Of Extreme Precipitation Events In The United States: 1895–2000, Kenneth E. Kunkel, David R. Easterling, Kelly Redmond, Kenneth Hubbard

Papers in Natural Resources

A newly available data set of daily precipitation observations was used to study the temporal variability of the frequency of short-duration extreme precipitation events for 1895–2000 in the conterminous United States. Event durations of 1, 5, 10, and 30 day and return periods of 1, 5, and 20 year were analyzed. For all combinations of duration and return period, heavy precipitation frequencies were relatively high during the late 19th/early 20th Centuries, decreasing to a minimum in the 1920s and 30s, followed by a general increase into the 1990s. The frequencies at the beginning of the 20th Century were nearly as …

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State-Space Discretization Of The Kalinin-Milyukov-Nash Cascade In A Sample-Data System Framework For Streamflow Forecasting, Jozsef Szilagyi Jan 2003

State-Space Discretization Of The Kalinin-Milyukov-Nash Cascade In A Sample-Data System Framework For Streamflow Forecasting, Jozsef Szilagyi

Papers in Natural Resources

No abstract provided.

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Survival Rates And Recovery Distributions Of Canada Geese Banded In Nebraska, Larkin A. Powell, Mark Vrtiska, Nick Lyman Jan 2003

Survival Rates And Recovery Distributions Of Canada Geese Banded In Nebraska, Larkin A. Powell, Mark Vrtiska, Nick Lyman

Papers in Natural Resources

We analyzed banding and recovery data for Canada geese (Branta canadensis) banded in Nebraska during 1990–2000. Survival rates were lower during 1996–2000 (adult: 0.688, SE = 0.016; juvenile: 0.611, SE = 0.029), than 1990–1995 (adult: 0.727, SE = 0.011; juvenile: 0.639, SE = 0.024). Average juvenile-to-adult ratio from banding data was 0.834 (SD = 0.485), resulting in an annual population growth rate (λ) estimate for 1990–1995 of 0.995 (95% CI = 0.021), and 0.922 (0.018) for 1996–2000. Our recovery analysis suggests that 67% of geese banded in Nebraska are shot in Nebraska. Over 30% of both juvenile and adult recoveries …

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Aggradation Of Gravels In Tidally Influenced Systems: Upper Albian (Lower Cretaceous) On The Cratonic Margin Of The North American Western Interior Foreland Basin., Robert L. Brenner, Gregory A. Ludvigson, Brian L. Witzke, Preston Lee Phillips, Timothy S. White, David F. Ufnar, Luis A. Gonzalez, R. Matthew Joeckel, Adrian Goettemoeller, Benjamin R. Shirk Jan 2003

Aggradation Of Gravels In Tidally Influenced Systems: Upper Albian (Lower Cretaceous) On The Cratonic Margin Of The North American Western Interior Foreland Basin., Robert L. Brenner, Gregory A. Ludvigson, Brian L. Witzke, Preston Lee Phillips, Timothy S. White, David F. Ufnar, Luis A. Gonzalez, R. Matthew Joeckel, Adrian Goettemoeller, Benjamin R. Shirk

Papers in Natural Resources

No abstract provided.

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Comment On "A Reappraisal Of The Kalman Filtering Technique As Applied In River Flow Forecasting" By M. Ahsan And K. M. O'Connor, Jozsef Szilagyi Jan 2003

Comment On "A Reappraisal Of The Kalman Filtering Technique As Applied In River Flow Forecasting" By M. Ahsan And K. M. O'Connor, Jozsef Szilagyi

Papers in Natural Resources

No abstract provided.

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Vadose Zone Influences On Aquifer Parameter Estimates Of Saturated-Zone Hydraulic Theory, Jozsef Szilagyi Jan 2003

Vadose Zone Influences On Aquifer Parameter Estimates Of Saturated-Zone Hydraulic Theory, Jozsef Szilagyi

Papers in Natural Resources

No abstract provided.

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Sensitivity Analysis Of Aquifer Parameter Estimations Based On The Laplace-Equation With Linearized Boundary Conditions, Jozsef Szilagyi Jan 2003

Sensitivity Analysis Of Aquifer Parameter Estimations Based On The Laplace-Equation With Linearized Boundary Conditions, Jozsef Szilagyi

Papers in Natural Resources

No abstract provided.

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Urban Canada Geese In Georgia: Assessing A Golf Course Survey And A Nuisance Relocation Program, Larkin A. Powell, Michael J. Conroy, Kipling S. Balkcom, Joe Caudell Jan 2003

Urban Canada Geese In Georgia: Assessing A Golf Course Survey And A Nuisance Relocation Program, Larkin A. Powell, Michael J. Conroy, Kipling S. Balkcom, Joe Caudell

Papers in Natural Resources

Nuisance complaints about Canada geese (Branta canadensis), have risen in recent years. In Georgia, managers have responded by relocating some nuisance geese to rural areas. During 1993–1996, we used band recoveries of relocated geese to determine the efficacy of relocation as a management strategy. We also used data from a post-card survey of golf courses to monitor the urban subpopulation of Canada geese in Georgia during 1998–2001. Flocks considered by golf course superintendents to be a nuisance were larger (1998: 48.8 geese, 1999: 71.5, 2000: 73.2, 2001: 67.2) than nonnuisance flocks (1998: 13.1 geese, 1999: 16.7, 2000: 25.8, 2001: 18.1). …

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Avhrr-Based Spectral Vegetation Index For Quantitative Assessment Of Vegetation State And Productivity: Calibration And Validation, Felix Kogan, Anatoly A. Gitelson, Edige Zakarin, Lev Spivak, Lubov Lebed Jan 2003

Avhrr-Based Spectral Vegetation Index For Quantitative Assessment Of Vegetation State And Productivity: Calibration And Validation, Felix Kogan, Anatoly A. Gitelson, Edige Zakarin, Lev Spivak, Lubov Lebed

Papers in Natural Resources

The goal of the work was to estimate, quantitatively, vegetation state and productivity using AVHRR-based Vegetation Condition Index (VCI). The VCI algorithm includes application of post-launch calibration to visible channels, calculation of NDVI from channels’ reflectance, removal of high-frequency noise from NDVI’s annual time series, stratification of ecosystem resources, and separation of ecosystem and weather components in the NDVI value. The weather component was calculated by normalizing the NDVI to the difference of the extreme NDVI fluctuations (maximum and minimum), derived from multi-year data for each week and land pixel. The VCI was compared with wheat density measured in Kazakhstan. …

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Towards A Unified Approach For Remote Estimation Of Chlorophyll-A In Both Terrestrial Vegetation And Turbid Productive Waters, Giorgio Dall'olmo, Anatoly Gitelson, Donald C. Rundquist Jan 2003

Towards A Unified Approach For Remote Estimation Of Chlorophyll-A In Both Terrestrial Vegetation And Turbid Productive Waters, Giorgio Dall'olmo, Anatoly Gitelson, Donald C. Rundquist

Papers in Natural Resources

In this study we tested the applicability of a method, originally developed for terrestrial plant leaves, to retrieve chlorophyll-a concentrations from reflectance spectra of turbid productive waters. We tuned the conceptual model according to the optical characteristics of the aquatic medium, and accurately predicted chlorophyll-a concentrations in water bodies over a wide range of optical conditions. Our results provide evidence that this technique may be considered as a general solution, independent of the type of medium, for assessing chlorophyll concentration in optically deep media using remotely sensed data.

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Remote Estimation Of Leaf Area Index And Green Leaf Biomass In Maize Canopies, Anatoly A. Gitelson, Andrés Viña, Timothy J. Arkebauer, Donald C. Rundquist, Galina P. Keydan, Bryan Leavitt Jan 2003

Remote Estimation Of Leaf Area Index And Green Leaf Biomass In Maize Canopies, Anatoly A. Gitelson, Andrés Viña, Timothy J. Arkebauer, Donald C. Rundquist, Galina P. Keydan, Bryan Leavitt

Papers in Natural Resources

Leaf area index (LAI) is an important variable for climate modeling, estimates of primary production, agricultural yield forecasting, and many other diverse studies. Remote sensing provides a considerable potential for estimating LAI at local to regional and global scales. Several spectral vegetation indices have been proposed, but their capacity to estimate LAI is highly reduced at moderate-to- high LAI. In this paper, we propose a technique to estimate LAI and green leaf biomass remotely using reflectances in two spectral channels either in the green around 550 nm, or at the red edge near 700 nm, and in the NIR (beyond …

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