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USGS2019

Current trends and future directions in swan research: Insights from the 6th International Swan Symposium

Given their popularity with researchers and public alike, together with their welldocumented importance in aquatic and terrestrial ecosystems, fundamental and applied research on swans continues to develop in the 21st century. The 6th International Swan Symposium (6th ISS), was held at the Estonian University of Life Sciences in Tartu, Estonia, in October 2018. The symposium brought together 101 delegates from 17 countries, with presentations on a range of topics on Cygnus and Coscoroba species, including monitoring, habitat and resource use, demography, movements and migration, and threats and conservation. The proceedings of the 6th ISS in this special issue of Wildfowl include select papers on swan research presented at the 6th ISS, covering a wide range of species, systems and issues. This paper presents a synthesis of the 6th ISS and an overview of current trends and future directions in swan research. Despite progress on many topics, southern hemisphere swan species continue to receive less attention than their northern hemisphere counterparts, whilst facing many of the same pressures. It is clear that, given the challenges facing swan researchers in the twenty-first century, international cooperation will continue to be vital. Swans are highly mobile animals and many populations undertake migrations spanning thousands of kilometres, and crucially do not recognise human geographic and political borders. Such international collaborations will be particularly important in coordinating future monitoring and conservation activities. The IUCN-SSC/Wetlands International Swan Specialist Group (SSG) will continue to facilitate international collaborations and communication among the global network of swan researchers, through its activities, website and annual newsletter. Given the substantial challenges and knowledge gaps documented here, there is no doubt that swan researchers will continue to benefit from regular symposia to share information and develop collaborations towards understanding and addressing emerging conservation issues. As such, we recommend holding International Swan Symposia every 4–5 years.

Wildfowl↗
USGS1993

Proceedings of the fourth conference on research in California's National Parks

The papers in this proceedings were selected from the 63 presentations given at the Fourth Biennial Conference on Research in National Parks in California. The overall theme for this meeting was a recurring one: “The Integration of Research into National Park Service Resource Management Decisions.” The conference was held at the University of California, Davis, on 10-12 September 1991 and was sponsored by the National Park Service Cooperative Park Studies Unit and the Institute of Ecology at the University of California, Davis. This proceedings highlights a variety of research and resource management efforts to improve the stewardship of our most treasured landscapes. In the future, it will become increasingly more important for federal and state agencies, university scientists and students, and the public to cooperate fully to improve the quantity and quality of science and resource management programs in units of the National Park System. As many of the papers in this proceedings attest, we must look beyond the political boundaries of protected landscapes to incorporate entire ecosystems. Competing resource uses inside and outside parklands must be reexamined to weave a common thread of biological conservation. As scientists, our studies must bridge the gap from plots to landscapes and from landscapes to regions. Our studies must built on information from species and populations to ecosystems and the processes that influence them. The papers in this proceedings are modest but important contribution to those ideals. Each paper represents original research and has been peer-reviewed. Many agencies, institutions, and individuals contributed in the development of this product. In the planning stages, National Park Service Western Region scientists provided advice and assistance in structuring the conference format. University of California, Davis, graduate students, directed by Sharon Lynch, assisted with logistics at the meeting, and provided general assistance with the paper sessions. We thank the students, technicians, and support staff who labored unselfishly behind the scenes to collect data and transfer information important to the completion of each paper. Financial support for this publication was provided with funds from the Western Region Resource Management and Resource Program and the Washington Office Servicewide Publications Program of the National Park Service. We thank Denny Fenn, Stan Albright, Bruce Kilgore, Dave Cherry, Gene Hester, and Donna O'Leary of the National Park Service and Charles Goldman of the University of California, Davis, Institute of Ecology for their support throughout the development of the proceedings. Finally, we are entering into a new age of research in the U.S. Department of the Interior. Recently, plans were announced for the creation of the National Biological Survey, dedicated to improving the quantity and quality of research necessary for the wise stewardship of our natural resources and wildlands. We welcome our new partners and pledge our full support to both the new and old agencies. The papers presented here--and past research efforts in national parks--provide an important stepping stone to the future. While many of us will be transferred administratively to the National Biological Survey, our emotional ties to the National Park Service mission of preserving resources for future generations will remain with us forever.

California↗
USGS2023

What is “big data” and how should we use it? The role of large datasets, secondary data, and associated analysis techniques in outdoor recreation research

With researchers increasingly interested in big data research, this conceptual paper describes how large datasets, secondary data, and associated analysis techniques can be used to understand outdoor recreation. Some types of large, secondary datasets that have been increasingly used in outdoor recreation research include social media, mobile device data, and trip reports or online reviews. First, we give a brief overview of big data terms and outline the steps involved in conducting big data research. In doing so, we describe data sources and analysis techniques relevant for outdoor recreation, and review how they have been applied in previous published works. We then describe opportunities, limitations, and considerations of using big data. Finally, we outline several questions researchers may consider when designing, conducting, reporting, and reviewing outdoor recreation research using big data. Overall, big data approaches can expand our understanding of outdoor recreation and, by addressing key questions, may help researchers harness the strengths of big data while ensuring quality and integrity.

Journal of Outdoor Recreation and Tourism↗
USGS1972

Geological Survey research 1972, Chapter C

This collection of 37 short papers is the second published chapter of "Geological Survey Research 1972." The papers report on scientific and economic results of current work by members of the Conservation, Geologic, and Water Resources Divisions of the U.S. Geological Survey. Chapter A, to be published later in the year, will present a summary of significant results of work done ~n fiscal year 1972, together with lists of investigations in progress, cooperating agencies, and Geological Survey offices. "Geological Survey Research 1972" is the thirteenth volume of the annual series Geological Survey Research. The twelve volumes already published are listed below, with their series designations.

Professional Paper↗
USGS2011

Measuring currents in submarine canyons: technological and scientific progress in the past 30 years

The development and application of acoustic and optical technologies and of accurate positioning systems in the past 30 years have opened new frontiers in the submarine canyon research communities. This paper reviews several key advancements in both technology and science in the field of currents in submarine canyons since the1979 publication of Currents in Submarine Canyons and Other Sea Valleys by Francis Shepard and colleagues. Precise placements of high-resolution, high-frequency instruments have not only allowed researchers to collect new data that are essential for advancing and generalizing theories governing the canyon currents, but have also revealed new natural phenomena that challenge the understandings of the theorists and experimenters in their predictions of submarine canyon flow fields. Baroclinic motions at tidal frequencies, found to be intensified both up canyon and toward the canyon floor, dominate the flow field and control the sediment transport processes in submarine canyons. Turbidity currents are found to frequently occur in active submarine canyons such as Monterey Canyon. These turbidity currents have maximum speeds of nearly 200 cm/s, much smaller than the speeds of turbidity currents in geological time, but still very destructive. In addition to traditional Eulerian measurements, Lagrangian flow data are essential in quantifying water and sediment transport in submarine canyons. A concerted experiment with multiple monitoring stations along the canyon axis and on nearby shelves is required to characterize the storm-trigger mechanism for turbidity currents.

Geosphere↗
USGS1965

Geological Survey research 1965, Chapter C

This collection of 44 short papers is the second published chapter of Geological Survey Research 1965. The papers report on scientific and economic results of current work by members of the Conservation, Geologic, and Water Resources Divisions of the U.S. Geological Survey.

Professional Paper↗
USGS1966

Geological Survey Research 1966, Chapter D

This collection of 44 short papers is the third published chapter of "Geological Survey Research 1966." The papers report on scientific and .economic results of current work by members of the Conservation, Geologic, and Water Resources Divisions of the U.S. Geological Survey.

Professional Paper↗
USGS1967

Geological Survey research 1967, Chapter B

This collection of 49 short papers is the first published chapter of "Geological Survey Research 1967." The papers report on scientific and economic results of current work. by members of the Geologic, Topographic, and Water Resources Divisions of the U.S. Geological Survey.

Professional Paper↗
USGS1968

Geological Survey research 1968, Chapter B

This collection of 44 short papers is the first published chapter of "Geological Survey Research 1968." The papers report on scientific and economic results of current work by 1ne1nbers of the Geologic, Topographic, and Water Resources Divisions of the U.S. Geological Survey. Chapter A, to be published later in the year, will present a summary of significant results of work done during fiscal year 1968, together with lists of investigations in progress, reports published, cooperating agencies, and Geological Survey offices.

Professional Paper↗
USGS1969

Geological Survey research 1969, Chapter B

This collection of 40 short papers is the first published chapter of "Geological Survey Research 1969." The papers report on scientific and economic results of current work by members of the Conservation, Geologic, and Water Resources Divisions of the U.S. Geological Survey. Chapter A, to be published later in the year, will present a summary of significant results of work done during fiscal year 1969, together with lists of investigations in progress, reports published, cooperating agencies, and Geological Survey offices.

Professional Paper↗
USGS1969

Geological Survey research 1969, Chapter D

This collection of 45 short papers is the third published chapter of "Geological Survey Research 1969." The papers report on scientific and economic results of current work by members of the Geologic, Topographic, and Water Resources Divisions of the U.S. Geological Survey. Chapter A, to be published later in the year, will present a summary of significant results of work done during fiscal year 1969, together with lists of investigations in progress, reports published, cooperating agencies, and Geological Survey offices.

Professional Paper↗
USGS1966

Geological Survey Research 1966, Chapter A

'Geological Survey Research 1966' is the seventh annual review of the econamic and scientific work of the U.S. Geological Survey. As in previous years the purpose of the volume is to make available promptly to the public the highlights of Survey investigations. This year the volume consists of 4 chapters (A through D) of Professional Paper 550. Chapter A contains a summary of significant results, and the remaining chapters are made up of collections of short technical papers. Many of the results summarized in chapter A are discussed in greater detail in the short papers or in reports listed in 'Publications in Fiscal Year 1966,' beginning on page A265. The tables of contents for chapters B through D are listed on pages A259-A264. Numerous Federal, State, county, and municipal agencies listed on pages A211-A215 cooperated financially with the Geological Survey during fiscal 1966 and have contributed significantly to the results reported here. They are identified where appropriate in the short technical papers that have appeared in Geological Survey Research and in papers published cooperatively, but generally are not identified in the brief statements in chapter A. Many individuals on the staff of the Geological Survey have contributed to 'Geological Survey Research 1966.' Reference is made to only a few. Frank W. Trainer, Water Resources Division, was responsible for organizing and assembling chapter A and for critical review of papers in chapters B-D, assisted by Louis Pavlides, Geologic Division. Marston S. Chase, Publications Division, was in charge of production aspects of the series, assisted by Jesse R. Upperco in technical editing, and William H. Elliott and James R. Hamilton in planning and preparing illustrations. The volume for next year, 'Geological Survey Research 1967,' will be published as chapters af Professional Paper 5715. Previous volumes are listed below, with their series designations. Gealagical Survey Research 1960-Prof. Paper 400 Gealagical Survey Research 1961-Prof. Paper 424 Gealagical Survey Research 1962-Prof. Paper 450 Gealagical Survey Research 1963-Prof. Paper 475 Gealagical Survey Research 1964-Prof. Paper 501 Gealagical Survey Research 1965-Prof. Paper 525

Professional Paper↗
USGS2025

Marginalizing time in habitat selection and species distribution models improves inference

Aim Recent methodological advances for studying how animals move and use space with telemetry data have focused on fine-scale, more mechanistic inference. However, in many cases, researchers and managers remain interested in larger scale questions regarding species distribution and habitat use across study areas, landscapes, or seasonal ranges. Point processes offer a unified framework for many methods applied in studies of species distribution and resource selection; however, challenges remain in terms of dealing with temporal autocorrelation common in many types of telemetry data collected from animal locations. Innovation Space–time point processes (STPPs) have a unique property, in that marginalising time offers a connection between individual animal movement and broader point processes, yet this property has seen little attention in both statistical and applied research. In this paper, we first present some of the details of this marginalisation property and methods for applying marginalised STPPs (mSTTPs) to autocorrelated telemetry data and then apply a mSTTP in a case study on the summer space use and habitat selection of female caribou ( Rangifer tarandus ) in Denali National Park and Preserve, Alaska. Main Conclusions The case study demonstrated that an mSTPP approach can improve inference over other commonly used methods in terms of its ability to account for temporal autocorrelation and offers greater precision in parameter estimates and improved predictions of space use. As this method fits conveniently into the existing point process frameworks, it offers a practical solution to dealing with temporal autocorrelation inherent to many types of telemetry data when research questions center around broader scale patterns of animal habitat selection and space use.

Alaska↗
USGS2025

Applications of unoccupied aerial systems (UAS) in landscape ecology: A review of recent research, challenges and emerging opportunities

Context Unoccupied aerial systems/vehicles (UAS/UAV, a.k.a. drones) have become an increasingly popular tool for ecological research. But much of the recent research is concerned with developing mapping and detection approaches, with few studies attempting to link UAS data to ecosystem processes and function. Landscape ecologists have long used high resolution imagery and spatial analyses to address ecological questions and are therefore uniquely positioned to advance UAS research for ecological applications. Objectives The review objectives are to: (1) provide background on how UAS are used in landscape ecological studies, (2) identify major advancements and research gaps, and (3) discuss ways to better facilitate the use of UAS in landscape ecology research. Methods We conducted a systematic review based on PRISMA guidelines using key search terms that are unique to landscape ecology research. We reviewed only papers that applied UAS data to investigate questions about ecological patterns, processes, or function. Results We summarize metadata from 161 papers that fit our review criteria. We highlight and discuss major research themes and applications, sensors and data collection techniques, image processing, feature extraction and spatial analysis, image fusion and satellite scaling, and open data and software. Conclusion We observed a diversity of UAS methods, applications, and creative spatial modeling and analysis approaches. Key aspects of UAS research in landscape ecology include modeling wildlife micro-habitats, scaling of ecosystem functions, landscape and geomorphic change detection, integrating UAS with historical aerial and satellite imagery, and novel applications of spatial statistics.

Landscape Ecology↗
USGS1996

Proceedings of the ocean drilling program: New Jersey continental slope and rise

The Scientific Results volumes of the Proceedings of the Ocean Drilling Program contain specialty papers presenting the results of extensive research in various aspects of scientific ocean drilling. The authors of the papers published in this volume have enabled future investigators to gain ready access to the results of their research, and I acknowledge their contributions with thanks. Each paper submitted to a Scientific Results volume undergoes rigorous peer review by at least two specialists in the author's research field. A paper typically goes through at least one revision cycle before being accepted for publication. We seek to maintain a peer-review system comparable to those of the most highly regarded journals in the geological sciences. Each Scientific Results volume has an Editorial Review Board that is responsible for obtaining peer reviews of papers submitted to the volume. This board usually is made up of the two co-chief scientists for the cruise, the ODP staff scientist for the cruise, and one external specialist who is familiar with the geology of the area investigated. In addition, the volume has an ODP staff editor who assists with manuscripts that require English-language attention and who coordinates volume assembly. Scientific Results volumes may also contain short reports of useful data that are not ready for final interpretation. Papers of this type, which may be found together in a section in the back of the volume, are called Data Reports and include no interpretation of results. Data Report papers are read carefully by at least one specialist to make sure they are well organized, comprehensive, and discuss the techniques or procedures thoroughly. To acknowledge the contributions made by this volume's Editorial Review Board, the Board members are designated Editors of the volume and are so listed on the title page. Reviewers of manuscripts for this volume, whose efforts are so essential to the success of the publication, are listed in the front of the book, without attribution to a particular manuscript. On behalf of the Ocean Drilling Program, I extend sincere appreciation to members of the Editorial Review Boards and to the reviewers for giving their generous contribution of time and effort, which ensures that only papers of high scientific quality are published in the Proceedings .

Book↗
USGS2010

Advances in estimation methods of vegetation water content based on optical remote sensing techniques

Quantitative estimation of vegetation water content (VWC) using optical remote sensing techniques is helpful in forest fire assessment, agricultural drought monitoring and crop yield estimation. This paper reviews the research advances of VWC retrieval using spectral reflectance, spectral water index and radiative transfer model (RTM) methods. It also evaluates the reliability of VWC estimation using spectral water index from the observation data and the RTM. Focusing on two main definitions of VWC—the fuel moisture content (FMC) and the equivalent water thickness (EWT), the retrieval accuracies of FMC and EWT using vegetation water indices are analyzed. Moreover, the measured information and the dataset are used to estimate VWC, the results show there are significant correlations among three kinds of vegetation water indices (i.e., WSI, NDII, NDWI 1640 , WI/NDVI) and canopy FMC of winter wheat ( n =45). Finally, the future development directions of VWC detection based on optical remote sensing techniques are also summarized.

Science China Technological Sciences↗
USGS2010

Measurement of dissolved organic matter fluorescense in aquatic environments: An interlaboratory comparison

The fluorescent properties of dissolved organic matter (DOM) are often studied in order to infer DOM characteristics in aquatic environments, including source, quantity, composition, and behavior. While a potentially powerful technique, a single widely implemented standard method for correcting and presenting fluorescence measurements is lacking, leading to difficulties when comparing data collected by different research groups. This paper reports on a large-scale interlaboratory comparison in which natural samples and well-characterized fluorophores were analyzed in 20 laboratories in the U.S., Europe, and Australia. Shortcomings were evident in several areas, including data quality-assurance, the accuracy of spectral correction factors used to correct EEMs, and the treatment of optically dense samples. Data corrected by participants according to individual laboratory procedures were more variable than when corrected under a standard protocol. Wavelength dependency in measurement precision and accuracy were observed within and between instruments, even in corrected data. In an effort to reduce future occurrences of similar problems, algorithms for correcting and calibrating EEMs are described in detail, and MATLAB scripts for implementing the study's protocol are provided. Combined with the recent expansion of spectral fluorescence standards, this approach will serve to increase the intercomparability of DOM fluorescence studies.

Environmental Science & Technology↗
USGS2018

A spatio-contextual probabilistic model for extracting linear features in hilly terrain from high-resolution DEM data

This paper introduces our research in developing a probabilistic model to extract linear terrain features from high resolution DEM (Digital Elevation Model) data. The proposed model takes full advantage of spatio-contextual information to characterize terrain changes. It first derives a quantifiable measure of spatio-contextual patterns of linear terrain feature, such as ridgelines, valley lines and crater boundaries, and then adopts multiple neighborhood analysis and a probability model to address data uncertainty in terrain surface modeling. Different from traditional approaches, the proposed model has the ability to achieve near-automated processing, and to support effective extraction of terrain features in both smooth and rough surfaces. Through a series of experiments, we demonstrate that the proposed approach outperforms existing techniques, including: thresholding, stream/drainage network analysis, visual descriptor, object-based image analysis and edge detection. We hope this work contributes to both the geospatial data science and geomorphology communities with a new way of utilizing high-resolution imagery in terrain analysis.

International Journal of Geographical Information ↗