scholarly journals MINERAL COMPOSITION OF NATURAL GOLD-CONTAINING GARNET-MAGNETITE SCHLICH OF THE SOUTH-WESTERN COAST OF KAMCHATKA

2018 ◽  
pp. 107-113
Author(s):  
V.E. Kungurova
Keyword(s):  
Mineral Composition ◽  
Western Coast ◽  
The South

Growth and movement of the South African abalone Haliotis midae: A reassessment

1995 ◽  
Vol 46 (3) ◽  
pp. 583 ◽  
Author(s):  
RJQ Tarr
Keyword(s):  
South African ◽  
Growth Rates ◽  
Growth Parameters ◽  
Eastern Coast ◽  
Island Population ◽  
Western Coast ◽  
Eastern Cape ◽  
The South ◽  
Significant Difference ◽  
Haliotis Midae

Growth rates of a number of Haliotis midae populations around the South African coast were studied by means of tagging. These populations ranged from the cool waters of the western coast to the more temperate environment of the eastern Cape. Standard von Bertalanffy growth curves were fitted and growth parameters derived. These ranged from 0.19 to 0.25 for K, the average rate at which L∞ is approached, and from 156 to 173 for L∞, the average theoretical maximum length. These indicate far higher growth rates than were previously published for this commercially fished species, and the reasons for this difference are discussed. The expectation that growth rates would be fastest in the warmer eastern Cape waters was not realized, there being no significant difference in growth between the Bird Island population on the eastern coast and the Robben Island population on the western coast. These new growth parameters indicate that H. midae in the commercial fishery grounds is attaining sexual maturity some four years earlier, and the minimum legal size some five years earlier, than previously considered. This has considerable significance for modelling studies presently underway. Movement of a small population of adult H. midae was studied over a three-year period, after which 47% of the original abalone were still present on the study site. Of these, 81.5% still occupied exactly the same position on the rocks. This indicates that H. midae that have located an optimum habitat, and that are not disturbed, tend not to move.

The significance of Drought, Disease and Famine in the agriculturally marginal zones of West-Central Africa

1982 ◽  
Vol 23 (1) ◽  
pp. 17-61 ◽  
Author(s):  
Joseph C. Miller
Keyword(s):  
Central Africa ◽  
Western Coast ◽  
African History ◽  
Way Of Life ◽  
The South ◽  
Epidemiological Factors ◽  
Documentary Sources ◽  
West Central ◽  
Marginal Zones ◽  
To Receive

Some 170 references to drought and disease along the south-western coast of Central Africa between 1550 and 1830 suggest that climatic and epidemiological factors motivated the farmers and herders of West-Central Africa in historically significant ways. Nearly all references come from documentary sources and so bear primarily on conditions in the drier and less fertile areas near Luanda and to the south, where African reactions would have been strongest.While minor shortages of rain occurred too frequently to receive much explicit attention in the documents, longer droughts spread more widely every decade or so and attracted notice. Major periods of dryness, extending for seven years or more and touching all parts of the region, occurred perhaps once each century and produced comments throughout the documentation.Localized minor droughts hardly disrupted the lives of Africans, who had presumably devised agricultural and pastoral strategies to take account of such ordinary climatic variation. Two-or three-year rainfall shortages produced banditry and warfare that often attracted Portuguese military retaliation. Major droughts disrupted polities and societies and hence coincided with major turning points in West-Central African history in the late sixteenth and late eighteenth centuries. In the earlier case, agricultural failures produced the famed ‘Jaga’ or Imbangala warriors, who elevated pillage to a way of life and who joined the Portuguese in establishing the Angolan slave trade. The later, protracted drought from 1784 to 1793 coincided with the historic peak of slave exports from West-Central Africa.

Genetic diversity ofSorghumhalepense(L.) Pers. in Iran as revealed by IRAP markers

2015 ◽  
Vol 14 (2) ◽  
pp. 132-141 ◽  
Author(s):  
Azimeh Karimi ◽  
Hojjatollah Saeidi
Keyword(s):  
Genetic Diversity ◽  
Caspian Sea ◽  
Crop Improvement ◽  
Northern Region ◽  
Western Coast ◽  
Zagros Mountains ◽  
The South ◽  
The West ◽  
North West ◽  
Irap Markers

Sorghum halepensegrows in a vast range of ecological regions of Iran. In this study, inter-retrotransposon amplified polymorphism (IRAP) markers were used to assess the genetic diversity of 38 accessions ofS. halepenseand two accessions ofSorghum bicolor(used as out groups) collected from different regions of Iran. In total, 180 DNA fragments were amplified from eight combinations of IRAP primers, from which 178 (98.9%) were polymorphic. The IRAP-based trees and two-dimensional plot of principal coordinate analysis demonstrated six different groups corresponding to their geographical origin in Iranian germplasm ofS. halepense: (1) in the south-west region; (2) in the west along the Zagros Mountains; (3) in the north-west of the country; (4) in the centre of the country; (5) and (6) in the northern region along the eastern and western coast of Caspian Sea. The most variable populations were found in the centre and the west of Iran. The results showed high gene flow among different regions, although the south-western accessions were well differentiated from those growing in other regions. The accessions collected from western coast of Caspian Sea were differentiated from neighbouring regions in both morphological characters and IRAP data. The measured genetic distances were independent of geographical distances. This survey demonstrates high genetic dynamism in Iranian germplasm ofS. halepenseand indicates that the present germplasm is of great value in terms of sampling for new alleles for crop improvement.

scholarly journals A PROPOSAL FOR WAVE ENERGY CONVERSION NEAR CAPE TOWN

1982 ◽  
Vol 1 (18) ◽  
pp. 16
Author(s):  
G. De F Retief ◽  
G.K. Prestedge ◽  
F.P.J. Muller
Keyword(s):  
Energy Conversion ◽  
Wave Energy ◽  
Three Dimensional ◽  
Cost Effective ◽  
Western Coast ◽  
Wave Energy Conversion ◽  
The South ◽  
Temporal And Spatial Distribution ◽  
Local Conditions ◽  
Coast Line

The South African wave energy program has been underway for several years and has included an analysis of the temporal and spatial distribution of wave energy along the full coast-line, determination of energy attenuation perpendicular to the coast-line at a site on the south western coast, and the development of a wave energy converter which is most suited to local conditions and requirements. The resource analysis has shown that the inshore power levels occurring along the south western coast are as promising as any elsewhere in the world. A bottom mounted, V-shaped wave energy conversion device driving an air turbine has been found to be most suited to prevailing conditions. The conversion characteristics of the device are presented, based on 1:100 scale three dimensional and 1:50 scale two dimensional model studies. Preliminary design studies of the proposed conversion system have underlined its potential viability as a cost effective supplementary source of power.

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