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Fishers' Indigenous and local knowledge (ILK) has multidimensional contributions to improve fisheries and aquatic ecosystems science, ranging from algae to whales and including management, conservation, ecology, and impact assessment. The challenges are to sustain this knowledge, recognize its value, and to include ILK holders in resource management and decision-making. [ABSTRACT FROM AUTHOR]

Studies on scientific winches installed on oceanographic/fisheries research vessels (ORVs and FRVs, respectively) are distinguished by the winches’ unique design features and the important role they play with scientific experiments. It is impossible to draw general conclusions when analysing scientific winches used for fisheries sampling experiments on recently built ORVs. Few vessels are built each year and their dimensions and mission vary greatly. Thus, to consider the concept of traction factor and the possible ways in which equipment on fishing trawlers could be arranged and manoeuvred, a statistical analysis was carried out on newly built and refitted vessels from Spanish shipyards. The starting point was a sample of 125 boats, to which linear regression models were adjusted to explain the relationship between total traction and the traction for the fishing winch. As a result, three regression models-one for each kind of arrangement-were obtained. The next step involved analysing and modelling the dependence of the auxiliary winch traction on fishing winch traction. [ABSTRACT FROM AUTHOR]

While the oceans are vitally important for human life and the global economy, they have been under extraordinary pressure in recent decades due to human interactions and climate change. Launched in 1971, the Aquatic Sciences and Fisheries Abstracts (ASFA) database of over four million records serves as an invaluable information source about the oceans and other aquatic environments for use in research and decision-making, particularly due to its inclusion of both primary and grey literature. Since information production and use practices are rapidly changing, an assessment of use of the database and information needs of stakeholders was conducted, guided by the following questions: 1) What do individuals (researchers, practitioners, students, and decision makers) seeking aquatic sciences and fisheries information expect the global ASFA database will provide? 2) Have evolving information production practices and delivery technologies affected expectations of users of a database like ASFA? and 3) What action should the ASFA Secretariat take to ensure the development of the database continues to fulfil its mandate as a highly relevant and informative resource for all types of users worldwide? By means of surveys, interviews, and analysis of longitudinal usage data, users' views of ASFA's strengths, weaknesses, and potentially beneficial enhancements were identified. Based on the results of the use assessment, the ASFA Secretariat has implemented several substantial changes, including creating an open information platform containing grey literature, as well as restructuring its international affiliate partnership arrangement to facilitate involvement of new members in ongoing additions to the database. These changes, designed to make the information more easily found, accessible, and interoperable, will enable aquatic and fisheries scientists, managers, students, and decision makers to use relevant primary and grey literature from around the world and assist with ocean and coastal research efforts, mitigation of the effects of climate change, and reaching global sustainability goals. • Finding relevant information is vital in ocean and coastal management decision-making. • Usage studies helped to strengthen the global Aquatic Sciences and Fisheries Abstracts. • Improved access to ASFA is due to worldwide changes in information production and use. • Use of ASFA helps to reduce publication bias and information privilege. • ASFA aids in meeting the UN SDGs by including authors from underrepresented countries. [ABSTRACT FROM AUTHOR]

Summary: Digital elevation models (DEMs) are widely used in topographically-based hydrology models. Most researchers dealing with DEMs have worked exclusively with either grid or contour based techniques. Intercomparisons of these techniques are empirical in nature, few in number and limited to a small number of catchments. We examine the relative effects of these techniques on the distribution of the topographic index (TI) for nine idealised hillslope types and eight natural catchments (4.4–83km2) in southeast Australia. In particular we investigate the underlying causes for the frequently observed increase in the TI with grid size. A simple analytical model for a parallel-planar hillslope indicates that median TI is asymptotic with respect to the number of grid cells and a linear function of grid size. We demonstrate that the latter result holds for hillslopes with more complex geometry. Using a multiple flow direction algorithm, we find that hillslope geometry and flow partitioning affect the spatial pattern of the TI and the rate of change (M) of median TI with grid size. This makes it impractical to recommend general guidelines for the value of the directional parameter in flow partitioning algorithms. For the natural catchments we show that median TI is also a linear function of grid size and that there is some evidence for a linear relationship between M and the inverse of the median topographic slope. Throughout the investigation we find that contour DEMs are less sensitive to changes in resolution than grid DEMs. [Copyright &y& Elsevier]

Abstract: The release of organic contaminants from melting snow poses risks to aquatic and terrestrial organisms and to humans who rely on drinking water and food production from regions that are seasonally snow-covered. Measured and model-predicted spring peak concentrations in waters receiving snowmelt motivate a thorough investigation of organic contaminant behaviour during melting. On the basis of the current understanding of snow metamorphosis, snowmelt hydrology and chemical partitioning in snow, this critical review aims to provide a qualitative picture of the processes involved in the release of organic contaminants from a melting snowpack. The elution sequence of organic substances during snowmelt is strongly dependent on their environmental partitioning properties and the physical properties of the snowpack. Water-soluble organic contaminants can be discharged in greatly elevated concentrations at an early stage of melting, while the bulk of the hydrophobic chemicals attached to particles is often released at the end of the melt period. Melting of a highly metamorphosed and deep snowpack promotes such shock load releases, whereas a shallow snow cover over a relatively warm ground experiencing irregular melting over the winter season is unlikely to generate notable peak releases of organic substances. Meltwater runoff over frozen ground directly transfers contaminant shock loads into receiving water bodies, while permeable soils buffer and dilute the contaminants. A more quantitative understanding of the behaviour of organic contaminants in varying snowmelt scenarios will depend on controlled laboratory studies combined with field investigations. Reliable numerical process descriptions will need to be developed to integrate water quality and contaminant fate models. [Copyright &y& Elsevier]