River channel thalwegs (the line of lowest elevation within a valley or watercourse) are often dynamic, and sometimes hidden features of large river systems. Especially low slope or impounded systems. The thalweg is a critical geomorphological feature of river and reservoir systems and affects everything from sediment transport, to fisheries habitat, to algae or invasive plant control.
Thus a good bathymetric contour map is a necessary pre-requisite for effective river and reservoir management. Here, we walk you through how to use new real time technologies (C-MAP’s Genesis Live) to produce smooth, precise, and accurate maps of hidden river thalwegs all within one trip to the site and with automated post-processing with BioBase’s EcoSound. We’ll use an annotated image gallery to take you through this process.
Continue reading “Mapping Hidden Channels with Genesis Live”
A. Adams, M. De Jesus, G. Cummings, and M. Farooqi
Texas Parks and Wildlife Department, Inland Fisheries
Texas Parks and Wildlife Department Inland Fisheries (TPWD IF) biologists traditionally use “stand-alone” mapping interfaces to generate 2-dimensional (2-D) aerial outputs of fish habitat and benthic surveys of aquatic systems. Preliminary work has shown promise in the use of a different method, which generates interactive 3-dimensional (3-D) high-definition (HD) outputs. During field surveys, a Lowrance© Elite 9Ti GPS unit with TotalScan™ transducer was used to generate data points along boat transects on waterbodies of interest. A waterbody “Vegetation Analysis Report” and HD maps were then generated from these data using web-based mapping algorithms through BioBase©, and ArcMap 10.3© GIS software. Aquatic vegetation biovolume, bathymetric mapping, and benthic substrate composition outputs, produced by BioBase© aided biologists in selecting best management strategies, regarding aquatic vegetation management and angler access development at three central Texas impoundments. This tool can prove valuable to fisheries managers needing a higher resolution of survey results to fine-tune management strategies. At a cost of $2,5001 US for a yearlong subscription, cost-benefit would have to be assessed by individual users, based on their needs.
Continue reading “Utilization of a Web-Based Mapping Interface to Enhance Inland Fisheries Management Strategies in Texas”