Influence of river flow on rod catch of Atlantic salmon,Salmo salarL., from the lower River Derwent, north-west England

1995 ◽  
Vol 2 (1) ◽  
pp. 75-86 ◽  
Author(s):  
M. W. APRAHAMIAN ◽  
M. BALL
Keyword(s):  
Atlantic Salmon ◽  
River Flow ◽  
North West ◽  
River Derwent

The Structure of the Edale, Mam Tor and Castleton Area

1942 ◽  
Vol 79 (3) ◽  
pp. 188-196 ◽  
Author(s):  
O. T. Jones
Keyword(s):  
Black Shales ◽  
The West ◽  
North West ◽  
East And West ◽  
The Village ◽  
North And South ◽  
River Derwent

Edale lies in the valley of the River Noe about 3 miles north-west of Castleton. Near Edale End, about 2½ miles below the village, the Noe turns from a nearly east and west course to a nearly north and south course past Hope to join the River Derwent. In the neighbourhood of Edale the floor and lower flanks of the valley are formed of black shales known as the Edale Shales; they are overlain in succession by the Mam Tor Sandstones, the Shale Grit, the Grindslow Shales, and the coarse Kinder Scout Grits which form the great plateau of the Peak and the precipitous edge of Kinder Scout. North of the Edale valley the Mam Tor Sandstones reappear below the Shale Grit in Ashop Dale and Alport Dale. They occur also to the west of the valley in two narrow inliers just north of the railway in Roych Clough and Moor Clough.

Mechanisms for nitrogen supply to the Australian North West Shelf

1985 ◽  
Vol 36 (6) ◽  
pp. 753 ◽  
Author(s):  
PE Holloway ◽  
SE Humphries ◽  
M Atkinson ◽  
J Imberger
Keyword(s):  
River Flow ◽  
Tidal Flow ◽  
Vertical Mixing ◽  
Low Frequency ◽  
Transport Processes ◽  
Physical Processes ◽  
Mixing Processes ◽  
North West ◽  
Tidal Motion ◽  
The North

An upper bound for the rate of supply of new nitrate required to maintain the observed primary production on the North West Shelf is estimated to be 0.1 g N m-2 day -1. Nitrate concentrations over the shelf and slope regions are high ( > 100 mg N m-3, in water deeper than - 100 m and usually low (~10 mg N m-3), on the shelf. River flow is weak and carries little nutrient into the shelf waters and so it remains for ocean physical processes to advect and mix the nutrient-rich deep waters onto the shallower shelf regions to meet the nutrient demand. Several mechanisms are reviewed to determine their potential in carrying out the required transport processes. Estimates of the advection of nitrate onto the shelf show that both semi-diurnal tidal flow and low-frequency (periods > 35 h) upwelling events can each contribute approximately half the required demand, providing there is rapid use of nutrients. The upwelling events occur in summer and are associated with reversals of the south-west-flowing Leeuwin Current. Tropical cyclones are also shown to be capable of meeting a small, but significant, portion of the demand through enrichment of the surface layers in the offshelf waters by upwelling and vertical mixing. The enriched water can then be advected onto the shelf. Both tidal and internal tidal motion have the potential to transport nitrate onto the shelf from deeper water through vertical and horizontal mixing processes. However, these processes are difficult to quantify accurately. It is concluded that nitrogen is supplied to this shelf ecosystem by physical processes that are regular throughout the year, as opposed to large sporadic events that occur only once or twice a year.

scholarly journals A hydrological assessment of the November 2009 floods in Cumbria, UK

2012 ◽  
Vol 44 (1) ◽  
pp. 180-197 ◽  
Author(s):  
J. D. Miller ◽  
T. R. Kjeldsen ◽  
J. Hannaford ◽  
D. G. Morris
Keyword(s):  
River Flow ◽  
Frequency Estimation ◽  
Flood Frequency ◽  
Estimation Methods ◽  
Lake Levels ◽  
North West ◽  
The North ◽  
Flood Estimation ◽  
The Uk ◽  
Maximum Flows

In November 2009, record-breaking rainfall resulted in severe, damaging flooding in Cumbria, in the north-west of England. This paper presents an analysis of the river flows and lake levels experienced during the event. Comparison with previous maxima shows the exceptional nature of this event, with new maximum flows being established at 17 river flow gauging stations, particularly on catchments influenced by lakes. The return periods of the flood peaks are estimated using the latest Flood Estimation Handbook statistical procedures. Results demonstrate that the event has had a considerable impact on estimates of flood frequency and associated uncertainty. Analysis of lake levels suggests that their record high levels reduced their attenuating effect, significantly affecting the timing and magnitude of downstream peaks. The peak flow estimate of 700 m3s–1 at Workington, the lowest station on the Derwent, was examined in the context of upstream inputs and was found to be plausible. The results of this study have important implications for the future development of flood frequency estimation methods for the UK. It is recommended that further research is undertaken on the role of abnormally elevated lake levels and that flood frequency estimation procedures in lake-influenced catchments are reviewed.

scholarly journals Untangling Tales of Tropical Sardines: Local Knowledge From Fisheries in Timor-Leste

2021 ◽  
Vol 8 ◽  
Author(s):  
Kimberley Hunnam ◽  
Imelda Carlos ◽  
Michael P. Hammer ◽  
Joctan Dos Reis Lopes ◽  
David J. Mills ◽  
...  
Keyword(s):  
Local Knowledge ◽  
River Flow ◽  
Strong Association ◽  
Future Research ◽  
Individual Species ◽  
Developed Country ◽  
North West ◽  
The North ◽  
Timor Leste ◽  
Species Groups

Tropical sardines (Family Clupeidae) are an important component of many marine fisheries in the Indo-West Pacific region. In Timor-Leste, a small, less-developed country within this region, ‘sardiña’ are some of the more commonly caught and consumed fish. Yet there is little published information from Timor-Leste about the species composition of these fisheries, nor their biology or ecology. We document the knowledge of Timorese fishers on nine locally distinguished sardine types that contribute to fisheries, and relate these to at least nine species: four species of ‘Flat-bodied Sardinellas’ (Sardinella subg. Clupeonia spp.), one species of ‘Round-bodied Sardinella’ (Sardinella subg. Sardinella lemuru), two species of ‘Tropical Pilchards’ (Amblygaster spp.) and a ‘Tropical Herring’ species (Herklotsichthys quadrimaculatus), all from the Clupeidae family; and one Dussumieria species from the Dussumieriidae family. We record variations in local sardine names across the country and document aspects of fishers’ knowledge relevant to understanding and managing the fisheries, including local sardine species’ seasonality, habitat, movements, interannual variation, as well as post-harvest characteristics in relation to perishability. In general, local names relate more closely with groups of species than individual species, although some names also distinguish fish size within species-groups. The local knowledge identified in this study has immediate application to inform fisheries monitoring and management, and to identify areas for future research. Notably, Timorese fishers recognize and make use of the strong association between some sardine species-groups and seasonally turbid river plumes. While further research is required to understand the underlying mechanisms of this association, this emphasizes the need to consider coastal fisheries and fisher livelihood impacts when assessing any plans or proposals that may alter river flow or water quality. Fishers also recognize migratory behavior of some sardine species, in particular the Flat bodied Sardinellas (S. gibbosa and others) along the north-west coast of Timor-Leste and across the border into Indonesian West Timor. Such insights complicate and need to be accounted for in initiatives for co-management or community-based management of Timor-Leste’s coastal waters and their fisheries.

scholarly journals Evidence of Long-Distance Coastal Sea Migration of Atlantic Salmon, Salmo Salar, Smolts from Northwest England (River Derwent).

2021 ◽  
Author(s):  
Amy Green ◽  
Hannele Honkanen ◽  
Philip Ramsden ◽  
Brian Shields ◽  
Diego Delvillar ◽  
...  
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
West Coast ◽  
Irish Sea ◽  
Long Distance ◽  
Receiver Array ◽  
Combining Data ◽  
The Irish Sea ◽  
River Derwent ◽  
Feeding Grounds

Abstract Combining data from multiple acoustic telemetry studies has revealed that west coast England Atlantic salmon (Salmo salar L.) smolts use a northward migration pathway through the Irish Sea to reach their feeding grounds. 100 Atlantic salmon smolts were tagged in May 2020 in the River Derwent, northwest England as part of an Environment Agency/Natural England funded project. Three tagged smolts were detected on marine acoustic receivers distributed across two separate arrays from different projects in the Irish Sea. One fish had migrated approximately 262km in 10 days from the river mouth at Workington Harbour, Cumbria to the northernmost receiver array operated by the SeaMonitor project; this is the longest tracked marine migration of an Atlantic salmon smolt migrating from United Kingdom. This migrating fish displayed behaviours which resulted in fast northward migration. The remaining two fish were detected on a receiver array operated by a third project: “COMPASS”. These detections further provide evidence that migration to reach marine feeding grounds of salmon smolts from rivers draining into the Irish Sea is northerly. The pattern of these detections would not have been possible without the collaborative efforts of three distinct and separately funded projects to share data. Further work is required to fully understand migration trajectories in this species on the west coast of the British Isles.

scholarly journals Development of an Automated Approach for Updating of the Annual Runoff Module Map

2015 ◽  
Vol 2 ◽  
pp. 35
Author(s):  
N.V. Arefiev ◽  
N.S. Bakanovichus ◽  
A.A. Lyalina ◽  
N.V. Sudakova ◽  
T.S. Ivanov ◽  
...  
Keyword(s):  
Flow Rate ◽  
River Flow ◽  
Flow Characteristics ◽  
Flow Distribution ◽  
Computer Assisted ◽  
Gis Application ◽  
North West ◽  
Hydrological Data ◽  
Hydropower Potential

<p>Several Russian Hydropower Design and Research Institutes have recently fulfilled studies of hydropower potential estimation for NorthWest, Caucasian and Angara River’s regions in Russia. An approach to automate the calculation of river flow characteristics, based on the usage of annual flow rate map, was proposed and tested by the authors for the aims of the studies.</p><p>Annual river flow characteristics together with the terrain data are the most important data sources for evaluation of the hydropower potential.</p><p>A set of requirements was made for the approach and for automation of annual flow rate maps creation in order to provide ability for updates in every 5-10 years.</p><p>A problem of lack of hydrological data for small and medium sized rivers was faced. To determine the hydrological characteristics the Russian code specification "Determination of Design Hydrological Performance" was used for the conditions of the lack of hydrological data, methods of spatial interpolation were also used.</p><p>To solve the problems it is necessary to define the parameters of the annual flow distribution: average annual flow, variation coefficient, coefficient of skewness.</p><p>Mapping is based on the assumption of a smooth change of annual flow rate for any territory in accordance with the distribution of climatic and physiographic factors (topography, soil, groundwater depth, etc.).</p><p>Milestones of flow rate mapping included: preparation of hydrological initial data; creating of the updated flow rate maps; determination of the corrections to the influence of local azonal factors; estimation of the accuracy of flow characteristics calculations.</p><p>In order to update the annual flow rate maps a special GIS application “Hydrologist” was created. The GIS application includes computer-assisted tool for processing the hydrological data, import/export tools, tools for analysis of area zoning data, tools for analysis of annual flow rate values in centroids of drainage-basins, location of water stage gauges, also the old and updated flow rate maps.</p><p>The article deals with the approach description, main problems that were faced and presenting the results.</p><p>The technology has been applied for North-West, Volga and Siberian Federal Districts in Russia. Comparison of the created annual flow rate map with the previously used map shows that the updated map is better of acquiring hydrological data for small and medium sized rivers.</p>

Artesian conditions in the Chilterns Chalk aquifer (North West of the London Basin) and the implications for surface water - groundwater interactions

2021 ◽  
pp. SP517-2020-144
Author(s):  
Alessandro Marsili ◽  
Ilias Karapanos ◽  
Mahmoud Jaweesh ◽  
Daniel R. Yarker ◽  
Eleanor M. Powers ◽  
...  
Keyword(s):  
River Flow ◽  
Regional Scale ◽  
Tectonic Stress ◽  
Specific Information ◽  
Groundwater Abstraction ◽  
North West ◽  
Geophysical Logging ◽  
Flow Response ◽  
Rock Strata

AbstractThe Chalk is a principal aquifer which provides an important resource in Southeast England. For two centuries, it allowed the establishment of a thriving watercress-growing industry, indirectly through diverted stream flow and directly, through the drilling of flowing artesian boreholes. The distribution of artesian boreholes across different catchments, suggests a regional control on vertical groundwater flow within the New Pit and Lewes Chalk units. Interrogation of location-specific information points to the confining role of a few key marls within the New Pit Chalk Formation, which can be traced up-catchment to where they naturally outcrop or have been exposed by quarrying. Evidence is found in geophysical logging of a number of boreholes across catchments, confirming a consistent pattern of the spatial distribution of such key markers. When tectonic stress was applied to the various Chalk Formations, the marl bands would have reacted producing more plastic deformation and less fractures in comparison with rigid rock strata. Such scenario would have created the conditions for secondary aquifer units, giving the Chalk confining or semi-confining hydraulic characteristics on a regional scale. This conceptual understanding helps explain the reasons that the river flow response to reductions in groundwater abstraction varies across the flow duration curve.

scholarly journals Homing behaviour of Atlantic salmon (Salmo salar) during final phase of marine migration and river entry

2013 ◽  
Vol 70 (5) ◽  
pp. 794-802 ◽  
Author(s):  
Jan Grimsrud Davidsen ◽  
Audun Håvard Rikardsen ◽  
Eva Bonsak Thorstad ◽  
Elina Halttunen ◽  
Hiromichi Mitamura ◽  
...  
Keyword(s):  
Atlantic Salmon ◽  
Salmo Salar ◽  
River Flow ◽  
Horizontal Distribution ◽  
Diel Periodicity ◽  
Final Phase ◽  
Tidal Cycles ◽  
Swimming Depth ◽  
Marine Migration ◽  
Migratory Speed

Little is known about Atlantic salmon behaviour during the last phase of the marine homing migration and subsequent river entry. In this study, 56 adult Atlantic salmon in the Alta Fjord in northern Norway were equipped with acoustic transmitters. Salmon generally followed the coastline, but their horizontal distribution was also affected by wind-induced spreading of river water across the fjord. Mean swimming depth was shallow (2.5–0.5 m), but with dives down to 30 m depth. Timing of river entry was not affected by river flow, diel periodicity, or tidal cycles. Movements during the last part of the marine migration and river entry were unidirectional and relatively fast (mean 9.7 km·day−1). However, migratory speed slowed as salmon approached the estuary, with a significantly lower speed in the innermost part of the estuary than in the open fjord. Migration behaviour seemed not to be affected by handling and tagging, as there were no behavioural differences between newly tagged fish and those captured and tagged 1 year before their homing migration.

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