Observations of bottom intensification of temperature and velocity fluctuations induced by oblique tidal interactions with a slope

2006 ◽  
Vol 57 (3) ◽  
pp. 255 ◽  
Author(s):  
Jason P. Antenucci ◽  
Gregory N. Ivey
Keyword(s):  
Internal Wave ◽  
Energy Levels ◽  
High Frequencies ◽  
North West ◽  
Tidal Interactions ◽  
The North ◽  
Energy Inputs ◽  
Linear Internal Wave ◽  
Wave Signature

Long-term measurements of temperature and velocity collected at six depths in 302 m of water off the North West Cape of Western Australia (21°37′35″S, 113°56′11″E) revealed several periods of extreme near-bed currents. The dominant forcing at the site is the M2 tide, with energy levels generally decreasing as the bottom is approached. There is, however, a dramatic change in the energy distribution for all frequencies in excess of the M4 tidal frequency between 80 and 10 m above the seabed. Waves in this frequency bandwidth are critical to the local bottom slope and show a strong linear internal wave signature; however, they do not appear to conform with linear internal wave reflection theory. Dissipation estimates reveal energetic motions with dissipation rates of ~10−5 m2 s−3. Superimposed on this ambient state, three energetic events with duration varying between 8 and 24 h can also be detected. These are characterised by large increases in energy levels in the high-frequency range, and peak speeds varying from 0.59 m s−1 to 1.87 m s−1. These events appear to be driven by direct local energy inputs at high frequencies.

CURRENT STATE AND DEVELOPMENT PERSPECTIVES OF THE CASPIAN SPRAT FISHERIES

2018 ◽  
pp. 69-75
Author(s):  
Tatiana Vasilievna Pomogaeva ◽  
Aliya Ahmetovna Aseinova ◽  
Yuriy Aleksandrovich Paritskiy ◽  
Vjacheslav Petrovich Razinkov
Keyword(s):  
Food Item ◽  
Growth Potential ◽  
North West ◽  
Marine Fishery ◽  
The North ◽  
Current State ◽  
West Part ◽  
Eggs And Larvae ◽  
Intensive Growth

The article presents annual statistical data of the Caspian Research Institute of Fishery. There has been kept track of the long term dynamics of the stocks of three species of Caspian sprat (anchovy, big-eyed kilka, sprat) and investigated a process of substituting a food item of sprats Eurytemora grimmi to a small-celled copepod species Acartia tonsa Dana. According to the research results, there has been determined growth potential of stocks of each species. Ctenophoran-Mnemiopsis has an adverse effect on sprat population by eating fish eggs and larvae. Ctenophoram - Mnemiopsis is a nutritional competitor to the full-grown fishes. The article gives recommendations on reclamation of stocks of the most perspective species - common sprat, whose biological characteristics helped not to suffer during Ctenophoram outburst and to increase its population during change of the main food item. Hydroacoustic survey data prove the intensive growth of common sprat biomass in the north-west part of the Middle Caspian. According to the results of the research it may be concluded that to realize the volumes of recommended sprat catch it is necessary to organize the marine fishery of common sprat at the Russian Middle Caspian shelf.

Fertiliser N and P applications on two Vertosols in north-eastern Australia. 1. Comparative grain yield responses for two different cultivation ages

2008 ◽  
Vol 59 (3) ◽  
pp. 247 ◽  
Author(s):  
David W. Lester ◽  
Colin J. Birch ◽  
Chris W. Dowling
Keyword(s):  
Grain Yield ◽  
Yield Response ◽  
Average Yield ◽  
Crop Species ◽  
Winter Cereal ◽  
North West ◽  
The North ◽  
Winter Cereals ◽  
Eastern Australia

Nitrogen (N) and phosphorus (P) are the 2 most limiting nutrients for grain production within the northern grains region of Australia. The response to fertiliser N and P inputs is influenced partly by the age of cultivation for cropping, following a land use change from native pasture. There are few studies that have assessed the effects of both N and P fertiliser inputs on grain yield and soil fertility in the long term on soils with contrasting ages of cultivation with fertility levels that are running down v. those already at the new equilibrium. Two long-term N × P experiments were established in the northern grains region: one in 1985 on an old (>40 years) cultivation soil on the Darling Downs, Qld; the second in 1996 on relatively new (10 years) cultivation on the north-west plains of NSW. Both experiments consisted of fertiliser N rates from nil to 120 kg N/ha.crop in factorial combination with fertiliser P from nil to 20 kg P/ha.crop. Opportunity cropping is practiced at both sites, with winter and summer cereals and legumes sown. On the old cultivation soil, fertiliser N responses were large and consistent for short-fallow crops, while long fallowing reduced the size and frequency of N response. Short-fallow sorghum in particular has responded up to the highest rate of fertiliser N (120 kg N/ha.crop). Average yield increase with fertiliser N compared with nil for 5 short-fallow sorghum crops was 1440, 2650, and 3010 kg/ha for the 40, 80, and 120 kg N/ha, respectively. Average agronomic efficiency of N for these crops was 36, 33, and 25 kg grain/kg fertiliser N applied. This contrasts with relatively new cultivation soil, where fertiliser N response was generally limited to the first 30 kg N/ha applied during periods of high cropping intensity. Response to P input was consistent for crop species, VAM sensitivity, and starting soil test P level. At both the old and new cultivation sites, generally all winter cereals responded to a 10 kg P/ha application, and more than half of long-fallow sorghum crops from both sites had increased grain yield with P application. At the old cultivation site, average yield gain for 10 kg P/ha.crop treatment was 480 kg/ha for all winter cereal sowings, and 180 kg/ha for long-fallow sorghum. Short-fallow sorghum did not show yield response to P treatment.

Repeseed adaptation in Northern New South Wales. II.* Predicting plant development of Brassica campestris L. and Brassica napus L. and its implications for planting time, designed to avoid water deficit and frost

1978 ◽  
Vol 29 (4) ◽  
pp. 711 ◽  
Author(s):  
AS Hodgson
Keyword(s):  
Daily Rainfall ◽  
Planting Date ◽  
Intermediate Region ◽  
Brassica Napus L ◽  
Planting Dates ◽  
Linear Temperature ◽  
North West ◽  
The North ◽  
Moisture Deficit

Two experiments were conducted to determine the growing degree-day (D°) requirements of annual B. campestris and B. napus cultivars, and to evaluate their use in planning crop development strategies to avoid frost and moisture deficit at three locations. In the first experiment, base temperatures and D° requirements were calculated for four phases from planting to grain-filling, on the basis of linear temperature-development rate responses measured in the field at Tamworth, N.S.W. The phenological pattern of each species was predicted for several planting dates at locations representing the north-west slopes, northern tablelands and an intermediate region, by using long-term mean daily temperatures and calculated Do requirements. From these predictions and long-term mean daily rainfall and pan evaporation rates, the available soil moisture depletion was estimated for each planting date. For each location, planting date strategies for both species were evaluated for avoidance of frost and moisture deficit. The predicted optimum planting dates for B. napus and B. campestris were, respectively, 20 June and 5 August for the north-west slopes, 20 August and 1 October for the northern tablelands, and 30 June and 18 August for the intermediate region. In the second experiment, the influence of planting date on the grain yield of B. campestris and B. napus was studied in several seasons at each of the locations studied in the first experiment. The planting date that gave the highest yield varied between species and locations. B. campestris was favoured by later dates than B. napus. For both species these dates were earliest on the north-west slopes and latest on the northern tablelands. Yields of B. napus were higher than those of B. campestris at all locations when each species was planted at a favourable time. Predicted optimum planting dates from experiment 1 are discussed in relation to the field results from experiment 2. _____________________ *Part I, Aust. J. Agric. Res., 29: 693 (1978).

Long Term Changes in Abundance of Eggs of the Cornish Pilchard (Sardina Pilchardus Walbaum) Off Plymouth

1974 ◽  
Vol 54 (3) ◽  
pp. 641-649 ◽  
Author(s):  
A. J. Southward
Keyword(s):  
Small Scale ◽  
Personal Communications ◽  
North West ◽  
The North ◽  
History Of ◽  
Inshore Waters ◽  
Relationship Of ◽  
Hearsay Evidence ◽  
The Relationship

The inshore fishery for the pilchard in Cornish waters has existed for several hundred years, and such records as are available concerning fluctuation in catches and market conditions have been reviewed by Couch (1865), Cushing (1957) and Culley (1971). Although pilchard have been landed from Lyme Bay, from the eastern half of the Channel, and from the southern North Sea (Couch, 1865; Furnestin, 1945; Cushing, 1957; personal communications G. T. Boalch) the catches have usually been incidental to other fisheries and more sporadic than in Cornish waters. Traditionally there are three areas fished for the Cornish pilchard: on the north-west coast around St Ives; in Mounts Bay and towards the Scillies; and between the Lizard Pt and Bolt Tail in Devon (Couch, 1865; Culley, 1971). The latter region, constituting the inshore waters of south-east Cornwall and south Devon, effectively forms the eastern limits of the regular occurrence of commercial shoals. Knowledge of the breeding and life-history of the fish in this region has always been scarce and subject to much hearsay evidence (reviewed in Southward, 1963). Up to quite recently it was thought that the main spawning area lay well to the west of the entrance to the Channel, and it was not until the investigations reported by Corbin (1947,195°) a nd Cushing (1957)tnat it was conclusively shown that extensive spawning can occur within the English Channel from May to October. The relationship of the spawning in the western Channel to the other areas of spawning off the entrance to the Channel and in the northern Bay of Biscay is illustrated in a recent series of reports (Arbault & Boutin, 1968; Arbault & Lacroix-Boutin, 1969; Arbault & Lacroix, 1971; Wallace, P. D. & Pleasants, C. A., duplicated ICES meeting paper CM 1972/J: 8), and is further demonstrated by Demir & Southward (1974) in discussing the results of a study of small scale seasonal changes in spawning intensity in inshore waters.

scholarly journals Introduction of the species of the genera Cotoneaster Medik. and × Sorbocotoneaster pozdnjakovii Pojark. from the Sibirea flora in the Botanical Garden acad. A. V. Fomin of Taras Shevchenko National University of Kiev (message 2)

2021 ◽  
Vol 20 (1) ◽  
pp. 124-139
Author(s):  
A. T. Grevtsova ◽  
T. B. Vakulenko ◽  
N. S Nоnischenko
Keyword(s):  
New Species ◽  
Botanical Garden ◽  
Main Task ◽  
North West ◽  
The North ◽  
National University ◽  
Herbarium Collections

The main task of the expeditions was the search for the following species of natural Siberian flora and theintroduction of live plants and seeds to the Botanical Garden named after acad. A. V. Fomin: Cotoneaster mongolicus.C. neo-popvii, C. tjulinae, which are currently presented in our collection. In addition, long-term phenological observations in the conditions of the north-west of Ukraine allowed to isolate new species from the imported material: C. kyachticus.C. logginovii. They are described in the materials of the XIV and XVII conferences “Problems of botany of Southern Siberiaand Mongolia”. A trip to the lake Zun-Torei was dedicated to the search for C. mongolicus. As it turned out later, under theC. mongolicus mother’s plant, we dug up a plant different from the mother’s plant, to which we gave the name C. logginovii.This article provides materials to identify the parents pair in the formation of this hybrid pitchfork. For this purpose,materials of herbarium collections from the vicinity of the lake were used Zun-Torei experienced local botanists, as wellas personal fees. Comparison of the samples allowed to establish their identity with C. mongolicus, as well as to certify it asone of the parents of C. logginovii. Morphological descriptions of annual shoots leaves, flowers, fruits, seeds of three typesof Cotoneasters: C. megalocarpus, C. mongolicus, C. yakuticus; micrographs of endocarp of bones of the previous speciesand C. logginovii, C. melanocarpus, C. uniflorus are given. The herbarium samples of C. mongolicus collected in the areaof the lake Zun-Torey were analyzed. The material is illustrated with photographs of plants introduced in the north-westof Ukraine (Kiev). The introduction of plants by the method of genus complexes by F. N. Rusanov allowed to create theCotoneaster collection, which includes 200 taxa of the genus. In the Botanical Garden named after acad. A .V. Fomin fromthe flora of Siberia preserved 11 species of Cotoneaster: C. commixtus, C. kyachticus. C laxiflorus. C. logginovii, C. lucidus,C. neo-popovii, C. megalocarpus, C. mongolicus, C. tjulinae, C. uniflorus, C. yakuticus.

scholarly journals ANALYSIS OF THE “PRECIPITATION – SOIL – DRAINAGE” SYSTEM UNDER THE CONDITIONS OF CLIMATE CHANGE IN THE NORTH-WEST OF RUSSIA

2020 ◽  
Author(s):  
I. B. Uskov ◽  
◽  
K. G. Moiseyev ◽  
M. V. Nikolaev ◽  
O. V. Kononenko ◽  
...  
Keyword(s):  
Climate Change ◽  
Atmospheric Precipitation ◽  
Weather Conditions ◽  
Soil Drainage ◽  
Drainage Systems ◽  
North West ◽  
Term Operation ◽  
The North ◽  
Precipitation Regimes

Purpose: to analyze the soil-climatic and anthropogenic reasons of decreasing drainage efficiency of closed pottery tubular drainage on the reclaimed lands of the North-West of Russia under the observed local weather conditions against the background of global climate changes. Materials and methods. The objects of research are seasonal precipitation regimes, reclaimed lands and drainage systems of closed tubular drainage. The methods of applied mathematical statistics, the ensemble method of processing and generalization of climate forecasts of the Intergovernmental Panel on Climate Change (IPCC), modernized by the authors were used in research. Monitoring data on changes in the physical properties of soils of reclaimed lands during their long-term operation were obtained using laboratory agrophysical methods for studying samples taken in the field. Results. It is shown that under the conditions of the observed climatic changes, the frequency, intensity and extremeness of atmospheric precipitation are increased. Long-term exploitation of lands with a leaching drainage regime is accompanied by changes in the hydrophysical properties of soils, for example, the coefficient of heterogeneity of the subsurface horizons of soils texture of automorphic genesis decreased from 26 to 6. The system “precipitation – soil – drainage” in climatically abnormal weather conditions exceeding the initial calculated precipitation level mode by 10–20 %, is unable to ensure the removal of excess moisture from the root layer. Conclusions: when creating and reconstructing such reclamation drainage systems it is recommended to take into account the tendencies of changes in the spatial-temporal statistical structure of precipitation and to design technologies for regulating the water regime with systems for intercepting and diverting surface runoff on such reclaimed lands.

scholarly journals Long-Term Influences of Stunting, Being Underweight, and Thinness on the Academic Performance of Primary School Girls: The NW-CHILD Study

2021 ◽  
Vol 18 (17) ◽  
pp. 8973
Author(s):  
Xonné Haywood ◽  
Anita Elizabeth Pienaar
Keyword(s):  
South Africa ◽  
Academic Performance ◽  
Primary School ◽  
North West ◽  
The North ◽  
Bonferroni Adjustment ◽  
North West Province ◽  
School Girls ◽  
Over Time

Poor socio-economic status contributes to undernutrition which, in turn, can increase the risk of academic underachievement. This study wants to determine if stunting, being underweight, and thinness show long term relations with academic performance in primary school girls aged 6 to 13 in the North West province of South Africa. A randomized and stratified longitudinal research design including a baseline and two time-point measurements over seven school years was used. The sample included girls aged 6 to 13 years (N = 198) in the North West province of South Africa. Academic performance in the June school assessments and national and provincial assessments in grades 1, 4, and 7 were used to determine academic performance. Independent t-testing was used to determine differences between thinness, underweight and stunted girls as opposed to a reference group with no undernutrition indices. A repeated measures ANOVA and post hoc Bonferroni adjustment analyzed relations over time. Normal weight girls significantly outperformed stunted girls academically (p < 0.05) over time. Stunting had prolonged and significant negative influences on language, mathematics, and grade point average (p < 0.05). Early identification of undernutrition, especially stunting, is important for intervention and the implementation of timely prevention strategies, especially during early childhood years.

scholarly journals Conservation status and vocal and morphological description of the Grand Comoro Scops Owl Otus pauliani Benson 1960

1991 ◽  
Vol 1 (2) ◽  
pp. 123-133 ◽  
Author(s):  
M. Herremans ◽  
M. Louette ◽  
J. Stevens
Keyword(s):  
Conservation Status ◽  
Distinct Species ◽  
Forest Loss ◽  
Morphological Description ◽  
Suitable Habitat ◽  
North West ◽  
The North ◽  
Acridotheres Tristis ◽  
Indian Myna

SummaryThe Grand Comoro Scops Owl Otus pauliani, confined to forest on Mount Karthala on Grand Comoro, Indian Ocean, is a distinct species based on the evidence of its plumage and voice. In November 1989 studies of territorial calling birds at night revealed its presence between 1,000 and 1,900 m on the north, west and south flanks of the volcano, on which there exists some 10,000 ha of suitable habitat. As territory sizes may be only 5 ha, the population could well be over 1,000 pairs but, although this is encouraging, there remains a long-term threat from forest loss through habitat fragmentation (fires, logging) and the spread of the Indian Myna Acridotheres tristis.

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