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Conference Papers

Browse almost 5,000 conference papers authored by our scientists and refine search by topic, location, year, and advanced search.

Filter Total Items: 5326

Validation of the ASTER Global Digital Elevation Model Version 2 over the conterminous United States

The ASTER Global Digital Elevation Model Version 2 (GDEM v2) was evaluated over the conterminous United States in a manner similar to the validation conducted for the original GDEM Version 1 (v1) in 2009. The absolute vertical accuracy of GDEM v2 was calculated by comparison with more than 18,000 independent reference geodetic ground control points from the National Geodetic Survey. The root mean
Authors
Dean B. Gesch, Michael J. Oimoen, Zhen Zhang, David J. Meyer, Jeffrey J. Danielson

In situ determination of flocculated suspended material settling velocities and characteristics using a floc camera

Estimates of suspended sediment settling are necessary for numerical sediment models, water quality studies, and rehabilitation of coastal ecosystems. Settling of cohesive sediment, which is common in estuaries, is more difficult to quantify than noncohesive sediment because of flocculation. Flocs are composed of an aggregation of finer silts, clays, and organic material. Floc characteristics, suc
Authors
David H. Schoellhamer, Dan Haught, Andrew Manning

Estimating tag loss of the Atlantic Horseshoe crab, Limulus polyphemus, using a multi-state model

The Atlantic Horseshoe crab, Limulus polyphemus, is a valuable resource along the Mid-Atlantic coast which has, in recent years, experienced new management paradigms due to increased concern about this species role in the environment. While current management actions are underway, many acknowledge the need for improved and updated parameter estimates to reduce the uncertainty within the management
Authors
Catherine Alyssa Butler, Conor P. McGowan, J. Barry Grand, David Smith

Identifying the decision to be supported: a review of papers from environmental modelling and software

Two of the basic tenets of decision support system efforts are to help identify and structure the decisions to be supported, and to then provide analysis in how those decisions might be best made. One example from wetland management would be that wildlife biologists must decide when to draw down water levels to optimise aquatic invertebrates as food for breeding ducks. Once such a decision is iden
Authors
Richard S. Sojda, Serena H. Chen, Sondoss Elsawah, Joseph H.A. Guillaume, A.J. Jakeman, Sven Lautenbach, Brian S. McIntosh, A.E. Rizzoli, Ralf Seppelt, Peter Struss, Alexey Voinov, Martin Volk

Pre- and post-remediation characterization of acid-generating fluvial tailings material

The upper Arkansas River south of Leadville, Colorado, USA, contains deposits of fluvial tailings from historical mining operations in the Leadville area. These deposits are potential non-point sources of acid and metal contamination to surface- and groundwater systems. We are investigating a site that recently underwent in situ remediation treatment with lime, fertilizer, and compost. Pre- and po
Authors
Kathleen S. Smith, Katherine Walton-Day, Karin O. Hoal, Rhonda L. Driscoll, K. Pietersen

Life on the edge: corals in mangroves and climate change

Coral diseases have played a major role in the degradation of coral reefs in the Caribbean, including those in the US Virgin Islands (USVI). In 2005, bleaching affected reefs throughout the Caribbean, and was especially severe on USVI reefs. Some corals began to regain their color as water temperatures cooled, but an outbreak of disease (primarily white plague) led to losses of over 60% of the tot
Authors
Caroline S. Rogers, James J. Herlan

Assessing the vulnerability of human and biological communities to changing ecosystem services using a GIS-based multi-criteria decision support tool

In this paper we describe an application of a GIS-based multi-criteria decision support web tool that models and evaluates relative changes in ecosystem services to policy and land management decisions. The Santa Cruz Watershed Ecosystem Portfolio (SCWEPM) was designed to provide credible forecasts of responses to ecosystem drivers and stressors and to illustrate the role of land use decisions on
Authors
Miguel L. Villarreal, Laura M. Norman, William B. Labiosa

Modelling ecosystem service flows under uncertainty with stochiastic SPAN

Ecosystem service models are increasingly in demand for decision making. However, the data required to run these models are often patchy, missing, outdated, or untrustworthy. Further, communication of data and model uncertainty to decision makers is often either absent or unintuitive. In this work, we introduce a systematic approach to addressing both the data gap and the difficulty in communicatin
Authors
Gary W. Johnson, Robert R. Snapp, Ferdinando Villa, Kenneth J. Bagstad

Trends in fishery agency assessments of black bass tournaments in the southeastern United States

Studies conducted during the last 30 years have identified benefits and adverse impacts and have documented increased frequency of fishing tournaments. This study used information provided by state fisheries management agency administrators to measure the frequency of black bass (Micropterus spp.) tournaments in southeastern states and assessed how reported changes in tournament frequency have imp
Authors
M. Todd Driscoll, Kevin M. Hunt, Harold Schramm

Extending a prototype knowledge- and object-based image analysis model to coarser spatial resolution imagery: an example from the Missouri River

A prototype knowledge- and object-based image analysis model was developed to inventory and map least tern and piping plover habitat on the Missouri River, USA. The model has been used to inventory the state of sandbars annually for 4 segments of the Missouri River since 2006 using QuickBird imagery. Interpretation of the state of sandbars is difficult when images for the segment are acquired at d
Authors
Laurence L. Strong

Bayesian WLS/GLS regression for regional skewness analysis for regions with large crest stage gage networks

This paper summarizes methodological advances in regional log-space skewness analyses that support flood-frequency analysis with the log Pearson Type III (LP3) distribution. A Bayesian Weighted Least Squares/Generalized Least Squares (B-WLS/B-GLS) methodology that relates observed skewness coefficient estimators to basin characteristics in conjunction with diagnostic statistics represents an exten
Authors
Andrea G. Veilleux, Jery R. Stedinger, David A. Eash

Comparison of acoustic doppler current profiler and Price AA mechanical current meter measurements made during the 2011 Mississippi River Flood

The Mississippi River and Tributaries project performed as designed during the historic 2011 Mississippi River flood, with many of the operational decisions based on discharge targets as opposed to stage. Measurement of discharge at the Tarbert Landing, Mississippi range provides critical information used in operational decisions for the floodways located in Louisiana. Historically, discharge meas
Authors
Patrick O'Brien, David Mueller, Thad Pratt