D. Hansen results 313
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Sensitivity analysis of modeled soil water dynamics within variable rate irrigation zones for winter wheatNARA Subscribed
Understanding within-field and season variability of soil water supply and crop water stress is critical for successful variable-rate irrigation (VRI) management. The objectives of this study were to (1) assess within-field variability of field capacity (FC), wilting point (WP), total available water (TAW), and initial soil volumetric water content (VWC init ); (2) validate a water balance model based on the American Society o...
Small pelagic fish (SPF) are critical to the trophodynamic structure and function of marine systems and support some of the most valuable and socially important fisheries worldwide. Their “boom and bust” population dynamics, shifts in distribution, and importance as forage resources for other fish stocks place unique challenges to assessing and managing SPF. In response to these challenges, an international working group was f...
SNAPSHOT USA 2024: Year 6 of the Coordinated National Camera Trap Survey of the United StatesNARA Subscribed
Motivation SNAPSHOT USA is an annual, multi‐contributor camera trap survey of mammals across the United States. The growing SNAPSHOT USA dataset is intended for tracking the spatial and temporal responses of mammal populations to changes in land use, land cover and climate. These data will be useful for exploring the drivers of spatial and temporal changes in relative abundance and distribution, as well as the impacts of speci...
Greenhouse gas (GHG) emissions from coastal aquaculture are an emerging environmental concern, with implications for ecosystem sustainability and climate mitigation. In this preliminary field-based study, we quantified carbon dioxide (CO 2 ), methane (CH 4 ), and nitrous dioxide (N 2 O) fluxes from 35 randomly selected prawn farms in coastal Bangladesh, at a single time point using the floating chamber method, with concurrent...
Geographic Variation in the Diet of Red Knot ( Calidris canutus ) Chicks Reflects Local Prey CommunitiesNARA Subscribed
Aim To describe and compare the diets of an Arctic‐breeding shorebird, the Red Knot ( Calidris canutus ), across three geographically distinct breeding sites. We aimed to document the dietary patterns and identify key prey groups that characterise each population's foraging ecology. Location Northwest Alaska (Nome), Northeast Greenland (Zackenberg) and North‐Central Russia (Taimyr Peninsula). Taxon Red Knot (Aves: Calidris can...
Regional ecosystem responses to environmental drivers in cold‐water lakes evaluated using stable isotopes of salmonid fishesNARA Subscribed
Diverse environmental drivers influence food web energy and nutrient flows, a key ecosystem function, yet their relative importance remains poorly known. We compiled thousands of bulk stable isotope measurements (carbon and nitrogen) of brown trout ( Salmo trutta , n = 2854) and Arctic charr ( Salvelinus alpinus , n = 3062) from 120 cold‐water lakes across northern Europe, spanning 0.02 to 1090 km 2 in size, to quantify the re...
Marine megafauna species are affected by a wide range of anthropogenic threats. To evaluate the risk of such threats, species’ vulnerability to each threat must first be determined. We build on the existing threats classification scheme and ranking system of the International Union for Conservation of Nature (IUCN) Red List of Threatened Species by assessing the vulnerability of 256 marine megafauna species to 23 at‐sea threat...
Novel Method for Collecting Skin Microbiome Samples From Free‐Ranging Bottlenose DolphinNARA Subscribed
Cetacean skin microbiome samples are traditionally collected by swabbing the skin of captured animals or using skin tissue from remote biopsies. The effects of different sampling methods are not well understood, and factors such as swab type and storage methods may affect the microbiome. The objective of this study was to determine if samples collected by swabbing biopsied skin from bottlenose dolphins yield sufficient microbi...
Carbon dioxide activated biochars as mediators for reductive debromination of 1,2-dibromoethaneNARA Subscribed
The fuel additive and pesticide 1,2-dibromoethane (DBA) is a problematic organic pollutant found in soil and aquifers. Remediation methods face drawbacks because of undesirable by-products and slow rates of removal. Biochars (BCs) are catalysts of reductive dehalogenation in anoxic environments by the layered iron(II)-iron(III) hydroxide green rust (GR). However, so far, such catalytic properties have generally only been obser...