southern extremity
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2020 ◽  
Vol 40 (4) ◽  
pp. 628-635
Author(s):  
Caroline J. Blackmore ◽  
Jennifer R. Ovenden ◽  
Toby P. Piddocke ◽  
Les Christidis

Failure to consider genetic structure in fish populations when collecting aquaculture broodstock can negatively affect fitness, and hence conservation and management goals. Here we used mitochondrial DNA from the 5’ end of the control region (D-loop) and four microsatellite markers to evaluate population genetic structure in the Mangrove Jack Lutjanus argentimaculatus with a view to guiding broodstock collection at the southern extremity of its east Australian range. There was no evidence of genetic structure within the entire tropical, subtropical and temperate east Australian distribution of L. argentimaculatus. Although this species may exhibit clinal morphological and life-history variation at its southern range limit, we did not detect wide- or fine-scale spatial genetic structure to indicate the presence of non-random evolutionary processes. Broodstock collection of L. argentimaculatus need not be geographically restricted in eastern Australia, but fisheries management should consider variation in life history and recruitment success at the species’ edge.


2019 ◽  
Vol 59 (4) ◽  
pp. 617-640
Author(s):  
O. N. Kolesnik ◽  
A. N. Kolesnik ◽  
E. G. Vologina ◽  
A. A. Maryash

The data on mineralogical analysis of fine sand fractions in sediments accumulated in the southern part of the Chukchi Plateau during the Quaternary are presented. The associations and downcore distribution of the rock-forming and accessory minerals in relation to other characteristics are considered. The established climatically controlled mineralogical features, i. e. periodicity of warmings and coolings, can be used in solving a number of genetic problems, stratigraphic subdivision of sediments and paleoreconstructions.


2019 ◽  
Vol 10 (2) ◽  
pp. 9-18
Author(s):  
Ahmad Nabi ◽  
Xiaodong Liu ◽  
Zhijun Gong ◽  
Khalid Pervaiz ◽  
Abbas Ali ◽  
...  

In this study geomorphological and seismotectonic analyses were carried out in Karachi arc area, southernPakistan to locate relatively safe areas from earthquakes disasters. Karachi arc is the southern extremity of the Kirtharmountain chain that occupies a major part of southern Pakistan and is comprised of a number of narrow, elongatedmountain ranges, i.e. Laki, Kirthar, Khud, Pab and Mor ranges. Based on geomorphological and seismotectonicanalyses Karachi arc area has been divided into three parts. These parts are northern, frontal and southern part. Thenorthern part of Karachi arc is seismically active where minor to moderate (3-5.9Mb) earthquakes occurred. Somebasement structures in Sehwan area seem to be still active and affected by the present-day transpressional stress field.The frontal part of Karachi arc is also active as manifested by the existence of active faults in Jhimpir, Surjan andMeting areas. These embryonic structures in the eastern part of the Arc are indicators of active deformation of Karachiarc. Presently the active deformation is taking place in frontal and northern parts of the arc, while the southern part thathas experienced deformation prior to Quaternary time is inactive and is relatively stable geoblock. The instrumental andhistoric seismicity record of the adjoining areas of Karachi arc show that the area has experienced light to moderateseismic events (4-5.9) with occasional occurrence of strong and major earthquakes. Any major or strong event in Katchrift zone, Makran subduction zone and Ornach-Nal fault zone may cause intensity of VII to VIII in Karachi arc area aswell as Karachi city of environmental seismic intensity scale 2007.


Author(s):  
Ahmad Nabi ◽  
Xiaodong Liu ◽  
Zhijun Gong ◽  
Khalid Pervaiz ◽  
Abbas Ali ◽  
...  

In this study geomorphological and seismotectonic analyses were carried out in Karachi arc area, southernPakistan to locate relatively safe areas from earthquakes disasters. Karachi arc is the southern extremity of the Kirtharmountain chain that occupies a major part of southern Pakistan and is comprised of a number of narrow, elongatedmountain ranges, i.e. Laki, Kirthar, Khud, Pab and Mor ranges. Based on geomorphological and seismotectonicanalyses Karachi arc area has been divided into three parts. These parts are northern, frontal and southern part. Thenorthern part of Karachi arc is seismically active where minor to moderate (3-5.9Mb) earthquakes occurred. Somebasement structures in Sehwan area seem to be still active and affected by the present-day transpressional stress field.The frontal part of Karachi arc is also active as manifested by the existence of active faults in Jhimpir, Surjan andMeting areas. These embryonic structures in the eastern part of the Arc are indicators of active deformation of Karachiarc. Presently the active deformation is taking place in frontal and northern parts of the arc, while the southern part thathas experienced deformation prior to Quaternary time is inactive and is relatively stable geoblock. The instrumental andhistoric seismicity record of the adjoining areas of Karachi arc show that the area has experienced light to moderateseismic events (4-5.9) with occasional occurrence of strong and major earthquakes. Any major or strong event in Katchrift zone, Makran subduction zone and Ornach-Nal fault zone may cause intensity of VII to VIII in Karachi arc area aswell as Karachi city of environmental seismic intensity scale 2007.


Author(s):  
M. S. Knyazev

A new name in the rank of species, Hedysarum kulikovii Knjaz., is published for H. tscherkassovae Knjaz. var. intermedium Knjaz. The species occurs in mountain steppe near the southern extremity of the Ural mountain range between 50° and 52°30′ N, 56°30′ and 58°30′ E. It is characterized by evenly purple flowers (vs. bicolour with pink standard and white keel in H. tscherkassovae s. str. and H. razoumowianum Helm et Fisch. ex DC.), smooth and zigzag-curved legumes (vs. smooth and flat in H. tscherkassovae s. str., or rouleau-like folded and thorned in H. razoumowianum), bluish-green leaves remaining its colour when dry (vs. green, brown-green when dry in H. tscherkassovae s. str., or green, yellowish-green when dry in H. razoumowianum), densely hairy with appressed hairs, whitish calyx (vs. greenish, purple-tinged, thinner hairy). An identification key and map of distribution of H. kulikovii and some related species of Hedysarum sect. Multicaulia are presented.


The Condor ◽  
2013 ◽  
Vol 115 (2) ◽  
pp. 280-289 ◽  
Author(s):  
Brandt W. Meixell ◽  
Mark S. Lindberg ◽  
Paul B. Conn ◽  
Christian P. Dau ◽  
John E. Sarvis ◽  
...  

Abstract. The population of Tundra Swans (Cygnus columbianus columbianus) breeding on the lower Alaska Peninsula represents the southern extremity of the species' range and is uniquely nonmigratory. We used data on recaptures, resightings, and recoveries of neck-collared Tundra Swans on the lower Alaska Peninsula to estimate collar loss, annual apparent survival, and other demographic parameters for the years 1978– 1989. Annual collar loss was greater for adult males fitted with either the thinner collar type (0.34) or the thicker collar type (0.15) than for other age/sex classes (thinner: 0.10, thicker: 0.04). The apparent mean probability of survival of adults (0.61) was higher than that of immatures (0.41) and for both age classes varied considerably by year (adult range: 0.44–0.95, immature range: 0.25–0.90). To assess effects of permanent emigration by age and breeding class, we analyzed post hoc the encounter histories of swans known to breed in our study area. The apparent mean survival of known breeders (0.65) was generally higher than that of the entire marked sample but still varied considerably by year (range 0.26–1.00) and indicated that permanent emigration of breeding swans was likely. We suggest that reductions in apparent survival probability were influenced primarily by high and variable rates of permanent emigration and that immigration by swans from elsewhere may be important in sustaining a breeding population at and near Izembek National Wildlife Refuge.


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