Factors Determining Migration and Transformation of Mercury in the Mouths of Northern Rivers

The spatial and temporal distribution and relative abundance of juvenile lake sturgeon (Acipenser fulvescens) and benthic macroinvertebrates were examined in the Mattagami and Groundhog rivers, tributaries of the Moose River in northern Ontario, Canada. Relative density and diversity of the benthic fauna were low, the most common taxa being Ablabesmyia sp. (Diptera) and Hexagenia sp. (Ephemeroptera). Benthic organisms were most abundant in substrate dominated by sand and clay. An appreciable portion of the riverbed was strewn with wood chips and was particularly depauperate of macrobenthos. Lake sturgeon foraged exclusively on the benthos, especially taxa of Ephemeroptera, Diptera, and Trichoptera. Hexagenia was the only prey species in greater density in sturgeon stomachs than in the benthos. The largest concentration of juvenile lake sturgeon was found adjacent to substrate dominated by sand and clay. Gillnet catches of lake sturgeon suggest that they are more active at night, which may enhance their foraging success. In these northern rivers, the trophic status of juvenile lake sturgeon is marginalized by an impoverished food supply, in part the consequence of habitat loss resulting from anthropogenic activities.

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Comparative recruitment of the banana prawn, Penaeus merguiensis, in five estuaries of the south-eastern Gulf of Carpentaria, Australia

Marine and Freshwater Research ◽

10.1071/mf9870029 ◽

1987 ◽

Vol 38 (1) ◽

pp. 29 ◽

Cited By ~ 22

Author(s):

DJ Staples ◽

DJ Vance

Keyword(s):

Monsoon Season ◽

Size Composition ◽

Relative Magnitude ◽

The South ◽

South Eastern ◽

Catchment Areas ◽

Juvenile Population ◽

Northern Rivers ◽

Recruitment Patterns ◽

Penaeus Merguiensis

Recruitment patterns of postlarvae immigrating into mangrove nursery areas of five major estuaries around the south-eastern Gulf of Carpentaria, as well as juveniles emigrating offshore into coastal waters, were compared for the banana prawn, Penaeus merguiensis, from September 1978 to March 1979.. Although considerable variability was observed among rivers, some basic recruitment patterns were discernible. Recruitment of postlarvae tended to follow a 28-day cycle with increased immigration on alternate spring tides. Variability between rivers in the number of resident juvenile prawns at any one sampling time resulted mainly from differences in the relative magnitude of postlarval settlement from these monthly cohorts. After the first heavy rainfall of the monsoon season, the lower reaches of rivers with !xger catchment areas a!! ran fresh, setthg up a physica! barrier to further past larval immigration. In contrast, post larval immigration continued throughout the study period in the river with the smallest catchment. There was a trend for more successful immigration earlier in the more northern rivers. Offshore emigration was influenced by rainfall, tide height and number of resident juvenile prawns at the time of emigration. The relative importance of these three factors differed among rivers, depending on the timing of rainfall in relation to the timing of juvenile population changes and the degree of flooding. These local differences in the timing of emigration of juveniles could be detected in the abundance and size of adolescent prawns in the offshore coastal area of the south-eastern Gulf which in turn influenced the size composition of prawns available to the commercial fishery.

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The World Reference Base for Soils (WRB) and Soil Taxonomy: an appraisal of their application to the soils of the Northern Rivers of New South Wales

Soil Research ◽

10.1071/sr12144 ◽

2013 ◽

Vol 51 (3) ◽

pp. 167 ◽

Cited By ~ 7

Author(s):

David T. Morand

Keyword(s):

New South ◽

New South Wales ◽

Soil Classification ◽

Soil Taxonomy ◽

Reference Base ◽

South Wales ◽

The World ◽

World Reference Base ◽

Northern Rivers ◽

Soil Surveys

Few soil surveys in New South Wales have utilised international soil classifications. Extensive morphological and laboratory data collected during soil surveys in the Northern Rivers region provided a strong basis for correlation with the World Reference Base for Soil Resources (WRB), Soil Taxonomy (ST), and the Australian Soil Classification (ASC). Of the 32 reference soil groups comprising the WRB, 20 were present locally; nine of the 12 ST orders were present. After re-classification of soils, correlation of the ASC with the WRB and ST was undertaken. Soils not requiring extensive laboratory analysis for classification and sharing similar central concepts were the more straightforward to correlate. Several ASC orders have unique central concepts and were therefore difficult to correlate with any one WRB reference soil group or ST order/suborder. Other soils were difficult to correlate due to differences in definitions of similar diagnostic criteria. This is most applicable to soils with strong texture-contrast and those with natric conditions. Such soils are not adequately differentiated to suit the Northern Rivers conditions. Of the two international schemes, the WRB was easier to apply locally due to the relative simplicity of the scheme. Considering certain aspects of Australian soils would improve the applicability of the WRB as a truly international framework for soil classification and correlation. Amendments to both the ASC and WRB are suggested.

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Erosion of the frozen riversides of the northern rivers depending on the direction of the coastal slope

Vestnik MGSU ◽

10.22227/1997-0935.2018.9.1112-1124 ◽

2018 ◽

pp. 1112-1124

Author(s):

V. K. Debolsky ◽

I. I. Gritsuk ◽

D. N. Ionov ◽

O. J. Maslikova

Keyword(s):

Coastal Slope ◽

Northern Rivers

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On Forecasting Navigation Seasons with Markov Chains

World of Transport and Transportation ◽

10.30932/1992-3252-2019-17-2-16-25 ◽

2019 ◽

Vol 17 (2) ◽

pp. 16-25

Author(s):

N. A. Filippova ◽

V. N. Bogumil ◽

V. M. Belyaev

Keyword(s):

Markov Chains ◽

Forecast Accuracy ◽

Real Data ◽

Climatic Conditions ◽

Mathematical Apparatus ◽

The North ◽

Accurate Forecast ◽

Northern Rivers ◽

Time Of Operation ◽

Ice Phenomena

The transport network in the regions of the North of theRussian Federationbasically remains seasonal (waterways, winter roads). The duration of river shipping season, depending on the climatic conditions, is 110–160 days, and the time of operation of winter roads varies within 120–210 days. Under these conditions, the accuracy of predicting the beginning and end of shipping season for the northern rivers plays a very important role. The article proposes a method for forecasting the duration of ice phenomena in the areas of shipping routes based on the use of the mathematical apparatus of Markov chains. An estimate of probability of an accurate forecast is given, taking into account the conformity with Bayes theorem and related dependencies. Verification of the method on the basis of real data proved that the forecast accuracy and probability of its implementation were sufficient for timely and effective organisation of preparatory operations for next shipping season on northern navigable rivers.

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Sustaining evidence-based practice for young people who self-harm: a 4-year follow-up

Australian Health Review ◽

10.1071/ah042720094 ◽

2004 ◽

Vol 27 (2) ◽

pp. 94 ◽

Cited By ~ 1

Author(s):

Stewart Einfeld ◽

Margaret Tobin ◽

John Beard ◽

Elizabeth Evans ◽

Richard Buss ◽

...

Keyword(s):

Mental Health ◽

Young People ◽

Health Service ◽

New South ◽

Evidence Based ◽

Deliberate Self Harm ◽

South Wales ◽

Self Harm ◽

Northern Rivers

Stewart Einfeld is at the School of Psychiatry, University of New South Wales; the late Margaret Tobin was the Director of Mental Health, South Australia; John Beard is Head of the Northern Rivers University Department of Rural Health, University of Sydney; Elizabeth Evans is a Research Assistant at the School of Psychiatry, University of New South Wales; Richard Buss is the Area Manager, Northern Rivers Area Mental Health Service; Michael Dudley is a child psychiatrist at Prince of Wales Hospital and the School of Psychiatry, University of New South Wales.This report is dedicated to our late co-author Margaret Tobin, to honour her contribution to advancing the quality of mental health services.Objective: In 1998 and 1999, two NSW Area Health Services conducted the Youth At Risk of Deliberate Self Harm (YARDS) project. The YARDS project was designed to implement evidence-based service enhancements for the clinical management of young people with Deliberate Self Harm. This paper examines the extent to which service enhancements implemented during YARDS were maintained 4 years after the conclusion of the project and compares service quality with another NSW Area Health Service that did not participate in the YARDS project.Method: Staff from mental health services and emergency departments completed the Service Activity Scale, a measure developed for the YARDS project to assess the quality of health service response to individuals who present following a suicide attempt.Results: Results indicated that the service improvements made during the YARDS project were maintained 4years after the project ended. Furthermore, a significant difference was found between scores for services that participated in YARDS and services that did not participate in YARDS.Conclusions: These results suggest that projects such as YARDS which support evidence based service nhancements may be useful in improving the management of young people with deliberate self-harm, and that these improvements may be long-lasting.

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