Reconnaissance surveying of Bechevin Bay, AK using satellite-derived bathymetry

Recently, a remote sensing study has been conducted over Bechevin Bay Channel, Alaska as part of a collaboration project between NOAA and the U.S. Coast Guard (USCG). The goal of the study to develop a procedure to prioritize survey areas and plan the annual deployment of Aids to Navigation (AtoN) along the channel. Bechevin Bay is considered a priority for marine surveying because it constitutes the easternmost passage through the Aleutians from the Bering Sea to the Gulf of Alaska. The channel is located in a mud flat area, where every winter the passage is closed due to ice cover. As a result, the path of the channel may change after sea ice has melted. Because of the geographic location of Bechevin Bay, many resources are required in order to conduct an annual survey to map the channel’s path. The surveys are typically conducted by the USCG buoy tenders using small boats and reconnaissance-style single beam lines. This paper presents the use of single-image satellite-derived bathymetry (SDB) as an economic alternative approach. The study compares the performance using different band ratios. Datasets that were used in the study included Landsat 8 and WorldView 2 (WV-2) imagery

Nautical Chart Adequacy Evaluation Using Publicly-Available Data

The International Hydrographic Office (IHO) C-55 publication communicates the need to improve the collection, quality and availability of hydrographic data world-wide, while also monitoring and rectifying possible deficiencies and shortcomings that are presented on the chart. This task of evaluating the adequacy of nautical chart products poses a challenge to many national hydrographic offices. This stems from the dearth of readily available spatial information: namely, the lack of reliable and accessible vessel traffic data, and little means to assess the changing nature of both near-shore bathymetry and shoreline in a simple and reliable manner. In this paper, we present the potential use of automatic-identification system (AIS) data, satellite-derived bathymetry (SDB), and airborne-lidar bathymetry (ALB) to provide an operational procedure for evaluating the adequacy and completeness of information of NOAA charts. Preliminary results from three U.S. study sites are presented in this paper: Nantucket Sound, MA; Barnegat Bay Inlet, NJ; and Barataria Bay, LA. Based on the publically-available datasets it was possible to identify changes in the charts and develop a reconnaissance procedure to monitor these changes on a yearly basis

Macroalgae and Eelgrass Mapping in Great Bay Estuary Using AISA Hyperspectral Imagery.

Results Increases in nitrogen concentration and declining eelgrass beds in Great Bay Estuary have been observed in the last decades. These two parameters are clear indicators of the impending eutrophication for New Hampshire’s estuaries. The NH Department of Environmental Services (DES) in collaboration with the Piscataqua Region Estuaries Partnership adopted the assumption that eelgrass survival can be used as the target for establishing numeric water quality criteria for nutrients in NH’s estuaries. One of the hypotheses put forward regarding eelgrass decline is that an eutrophication response to nutrient increases in the Great Bay Estuary has been the proliferation of nuisance macroalgae, which has reduced eelgrass area in Great Bay Estuary. To determine the extent of this effect, mapping of eelgrass and nuisance macroalgae beds using hyperspectral imagery was suggested. A hyperspectral image was made by SpecTIR in August 2007 using an AISA Eagle sensor. The collected dataset was then used to map eelgrass and nuisance macroalgae throughout the Great Bay Estuary. Here we outline the procedure for mapping the macroalgae and eelgrass beds. Hyperspectral imagery was effective where known spectral signatures could be easily identified. Comprehensive eelgrass and macroalgae maps of the estuary could only be produced by combining hyperspectral imagery with ground-truth information and expert opinion. Macroalgae was predominantly located in areas where eelgrass formerly existed. Macroalgae mats have now replaced nearly 9% of the area formerly occupied by eelgrass in Great Bay

Deformation of the Cape Chignecto Pluton, Cobequid Highlands, Nova Scotia: thrusting at the Meguma-Avalon boundary

The Early Carboniferous Cape Chignecto pluton, at the western end of the Cobequid Highlands in the Avalon Terrane of Nova Scotia, consists predominantly of two-feldspar biotite granite. Intrusion of smaller diorite bodies locally melted and hybridized the granite. Diabase and microgranite dykes cut the plutons. Much of the pluton has a flat-lying mylonitic foliation, with a mineral elongation lineation trending between north and west. Quartz is dynamically recrystallized, but feldspars show predominantly brittle deformation. The phiton was probably deformed under greenschist facies conditions, after cooling. C-S fabrics observed in the field, and tails on porphyroclasts seen in thin section, indicate northward overthrusting. The Hadrynian Jeffers Group is thrust over the south edge of the phiton in the Fowler Brook inlier. At its north edge, the pluton is probably thrust over volcanic rocks of die Fountain Lake Group. The deformation of the pluton is constrained by stratigraphic relationships and isotopic dates to a Namurian or possibly early Westphalian age. Deformation within the pluton is correlated with Namurian uplift of the Cobequid and Caledonia Highlands. It records either transpression resulting from the curvature of the Meguma-Avalon boundary or a major component of convergent movement between the Meguma and Avalon terranes. RÉSUMÉ Le pluton de Cape Chignecto, daté du début du Carbonifere et situé à l'extremité occidentale des Monts Cobequid (Lanière d'Avalon, Nouvelle-Écosse), est formé en majeure partie de granite à biotite à deux feldspaths. Le granite subit une fonte et une hybridation locales lore de l’ intrusion de batis dioritiques de plus faibles dimensions. Des dykes de diabase et de microgranite recoupent les plutons. La majeure partie du pluton présente une foliation mylonitique horizontale, avec une linétion d'éirement orientée entre le nord et l’ouesL On note une recristallisation dynamique du quartz mais la déformation des feldspaths est surtout fragile. Le pluton fut probablement déformé sous des conditions appartenant au faciès des schistes verts, et ce après son refroidissement. Des fabriques planaires C-S, observées sur le terrain, et des ombres de pression dissymdtriques, vues en lame mince, indiquent un charriage vers le nord. Le Groupe hadrynien de Jeffers chevauche l'extrémité méridionale du pluton dans la fenetre de Fowler Brook. A son extrémité septentrionale, le pluton chevauche probablement les volcanites du Groupe de Fountain Lake. Les relations stratigraphiqueset des datations radiométriques limitent l'âge de la déformation du pluton au Namurien ou possiblement au début du Westphalien. On corrèle la déformation au sein du pluton avec la surrection namurienne des monts Cobequid et Caledonia. Cette déformation enregistre soil une transpression résultant de la cambrure de la jonction Meguma-Avalon, soil une forte composanle de mouvement convergent entre les lanières de Meguma et d* Avalon. [Traduit par le journal

Using Moored Arrays and Hyperspectral Aerial Imagery to Develop Eelgrass-based Nutrient Criteria for New Hampshire\u27s Great Bay Estuary

Increasing nitrogen concentrations and declining eelgrass beds in the Great Bay Estuary, NH are clear indicators of impending problems for the state’s estuaries. A workgroup established in 2005 by the NH Department of Environmental Services and the NH Estuaries Project (NHEP) adopted eelgrass survival as the water quality target for nutrient criteria development for NH’s estuaries. In 2007, the NHEP received grant from the U.S. Environmental Protection Agency to collect water quality information including that from moored sensors and hyper-spectral imagery data of the Great Bay Estuary. A second grant in 2008 was directed at determining the influence of nuisance macroalgae proliferation on eelgrass bed extent in the context of eutrophication. Here we present the results of these two projects with the spatial distributions of water quality, shallow water bathymetry, and the extent of eelgrass and macroalgae. The results are discussed with respect to eelgrass survivability models, historical eelgrass distributions, and using eutrophication responses in the Great Bay Estuary as a model for other northern, macrotidal estuaries. The expected outcome of this research will support the development of numeric nutrient criteria for NH’s estuaries

Human bony labyrinth is an indicator of population history and dispersal from Africa.

The dispersal of modern humans from Africa is now well documented with genetic data that track population history, as well as gene flow between populations. Phenetic skeletal data, such as cranial and pelvic morphologies, also exhibit a dispersal-from-Africa signal, which, however, tends to be blurred by the effects of local adaptation and in vivo phenotypic plasticity, and that is often deteriorated by postmortem damage to skeletal remains. These complexities raise the question of which skeletal structures most effectively track neutral population history. The cavity system of the inner ear (the so-called bony labyrinth) is a good candidate structure for such analyses. It is already fully formed by birth, which minimizes postnatal phenotypic plasticity, and it is generally well preserved in archaeological samples. Here we use morphometric data of the bony labyrinth to show that it is a surprisingly good marker of the global dispersal of modern humans from Africa. Labyrinthine morphology tracks genetic distances and geography in accordance with an isolation-by-distance model with dispersal from Africa. Our data further indicate that the neutral-like pattern of variation is compatible with stabilizing selection on labyrinth morphology. Given the increasingly important role of the petrous bone for ancient DNA recovery from archaeological specimens, we encourage researchers to acquire 3D morphological data of the inner ear structures before any invasive sampling. Such data will constitute an important archive of phenotypic variation in present and past populations, and will permit individual-based genotype-phenotype comparisons

The United States (US) Experience in Controlling Erosion: the Involvement of Government, Rural Vs. Urban Controls and the Blurring of Those Differences

Abstract: The United States (US) history and concern for erosion and its concequences is an interesting public policy study. Starting with the nation's settlement and founding in the 1700's, there is documentation that demonstrates our earliest settlers were aware of the problems caused by erosion as man disturbed the soil, and were interested in doing something to reduce it. With the advent of The War Between the States in 1861, there were documented cases of rivers and streams choked with sediment from poorly managed agricultural lands. With what looked to be unlimited land resources, it was common for farmers of that day to simply pick up their belongings and move west to new land when their original farms "wore out." The War also delayed the nations attention to erosion as a problem. Soon however, as the nation became more populated coast-to-coast, that was no longer an option. The great Plains "Dust Bowl" period in the 1930's, accompanied by the US Great Depression, became an opportunity for the Franklin D. Roosevelt Administration to deal with both unemployment and a natural resource problem. The federal Soil Erosion Service (SES) was established in the Department of Interior in 1933. The SES became the Soil Conservation Service (SCS) and was moved to the Department of Agriculture in 1935. In that same 1930's period, the states were passing legislation establishing the nation's first special purpose districts with erosion control as their principal mission. These Soil Conservation Disticts (SCD's), in partnership with the natural resource agencies in each state and the federal SCS, became the "three-legged stool" which has successfully attacked erosion in much of the US. In the 1970's, the US became concerned with accelerated erosion from construction sites in repidly expanding metropolitan areas. In addition to the normal problems of dealing with unwanted sediment, degraded water quality was also now recognized as a problem. How the US chose to deal with urban erosion is the second part of this story. The lines seperating agricultural and urban erosion are being blurred at a rapid rate. In addition to exploring US erosion control history, this paper will mention common land management practices, their development, use, and effectiveness. From simple land management practices such as crop rotation, to cultivating on the contour, planting alternate contout strips, designing and installing grassed waterways and diversions, to using man-made geotextiles, the technology of erosion control has changed. The US experience should be of interest to other nations as they attempt to deal with the erosion challenge. The International Erosion Control Association (IECA) plays a vital role in serving as a global resource for erosion control information

Protecting Puget Sound from CSOs by retrofitting Urban Neighborhoods with Green Stormwater Infrastructure

In 2009 King County Wastewater Treatment Division (KCWTD) selected green stormwater infrastructure (GSI) as the preferred alternative for controlling combined sewer overflows (CSO) for the 1100-acre Barton combined sewer system (CSS) basin in Seattle. In 2008 KCWTD reported that the basin had an average of four overflows per year that discharge a total of four million gallons into Puget Sound. In order to reduce the overflows to no more than one CSO event per year for Washington State’s Department of Ecology compliance, KCWTD retrofitted 15 residential streets with bioretention cells in order to intercept, treat and reduce the amount of stormwater discharging into the CSS. After filtering through the bioretention soil and plantings, stormwater discharges into an underdrain that conveys the flows into an underground injection control screen well for deep infiltration to a receptive soil layer beneath the area’s glacial till. Intercepting stormwater before it enters the CSS will reduce KCWTD’s annual treatment plant costs. The project completed construction of the first ten streets in 2014 and the remaining five streets in 2015. Our presentation will cover challenges confronted by this pioneering project (the first for KCWTD) from planning, design, community outreach, construction and through the first two years of operations and maintenance. We will also review how we balanced CSO control performance with community concerns and street performance so issues such as slope, planter width, existing utilities and trees, access, and on-street parking patterns were key design drivers; how KCWTD developed and implemented a new maintenance program for the wastewater treatment division; and how the team developed infrastructure that met current needs while incorporating flexibility to respond to an uncertain future and changing climate. Finally, we will provide the latest results in monitoring for CSO events in the basin for the first two years of operation and maintenance