scholarly journals Population dynamics of four insect defoliators in a dryland South Island Eucalyptus plantation

2016 ◽  
Vol 69 ◽  
pp. 321-321
Author(s):  
H. Lin ◽  
T.J. Murray ◽  
E.G. Mason
Keyword(s):  
Population Dynamics ◽  
Larval Abundance ◽  
Limited Information ◽  
The South ◽  
Eucalyptus Plantation ◽  
Island Populations ◽  
The North ◽  
Pest Outbreaks ◽  
Eucalyptus Plantations ◽  
Two Generations

Exotic insect defoliators originally from Australia are present in New Zealand Eucalyptus plantations Pest outbreaks causing significant defoliation can reduce tree growth and productivity There is limited information on the population dynamics of major Eucalyptus defoliators in the South Island Populations of four defoliators were monitored monthly from November 2015 to March 2016 in a dryland Eucalyptus plantation in Marlborough by assessing 35 shoots from each of 225 trees Only one generation of Paropsis charybdis was observed Peak adult abundance was in December/January and adults disappeared in March This is different from North Island and Australian studies in which two generations are often observed Opodiphthera eucalypti had two distinct generations with larval populations peaking in December and February/March Most Phylacteophaga froggatti larvae were found after December but populations were relatively low throughout the monitoring period Strepsicrates macropetana reached peak larval abundance in February and had multiple overlapping generations These results suggest differences in the population dynamics of eucalypt defoliators in the South Island compared to those reported in the North Differences are likely due to local environmental conditions which were notably dry during this particular monitoring season These data provide important information for pest management in South Island dryland Eucalyptus plantations

Inherited and Environmentally Induced Differences in Mutation Frequencies Between Wild Strains of Sordaria fimicola From “Evolution Canyon”

Genetics ◽  
1998 ◽  
Vol 149 (1) ◽  
pp. 87-99
Author(s):  
Bernard C Lamb ◽  
Muhammad Saleem ◽  
William Scott ◽  
Nina Thapa ◽  
Eviatar Nevo
Keyword(s):  
Genetic Variation ◽  
Spontaneous Mutation ◽  
The South ◽  
Natural Genetic Variation ◽  
The North ◽  
Ascospore Germination ◽  
Evolution Canyon ◽  
Two Generations ◽  
Wild Strains ◽  
Sordaria Fimicola

Abstract We have studied whether there is natural genetic variation for mutation frequencies, and whether any such variation is environment-related. Mutation frequencies differed significantly between wild strains of the fungus Sordaria fimicola isolated from a harsher or a milder microscale environment in “Evolution Canyon,” Israel. Strains from the harsher, drier, south-facing slope had higher frequencies of new spontaneous mutations and of accumulated mutations than strains from the milder, lusher, north-facing slope. Collective total mutation frequencies over many loci for ascospore pigmentation were 2.3, 3.5 and 4.4% for three strains from the south-facing slope, and 0.9, 1.1, 1.2, 1.3 and 1.3% for five strains from the north-facing slope. Some of this between-slope difference was inherited through two generations of selfing, with average spontaneous mutation frequencies of 1.9% for south-facing slope strains and 0.8% for north-facing slope strains. The remainder was caused by different frequencies of mutations arising in the original environments. There was also significant heritable genetic variation in mutation frequencies within slopes. Similar between-slope differences were found for ascospore germination-resistance to acriflavine, with much higher frequencies in strains from the south-facing slope. Such inherited variation provides a basis for natural selection for optimum mutation rates in each environment.

scholarly journals Spatial variability of planktonic invertebrate larvae in the Canary Islands area

2009 ◽  
Vol 90 (6) ◽  
pp. 1217-1225 ◽  
Author(s):  
J.M. Landeira ◽  
F. Lozano-Soldevilla ◽  
S. Hernández-León ◽  
E.D. Barton
Keyword(s):  
Time Series ◽  
Canary Islands ◽  
Larval Abundance ◽  
The South ◽  
The North ◽  
Larval Distribution ◽  
Eddy Structures ◽  
Anticyclonic Eddies ◽  
Invertebrate Larvae ◽  
Larval Group

In October 1991, invertebrate larvae abundances were analysed to study the influence of the disturbance of the Canary Current flow by the Canary Islands archipelago on the variability of larval distribution. Two transects and two time-series stations located to the north (non-perturbed zone) and the south (perturbed zone) of the Canary Islands were sampled. Oceanographical data showed a highly stratified water column and zonally uniform salinity and temperature seaward of the African upwelling in the non-perturbed zone, while the perturbed zone presented strong turbulence in the form of mesoscale eddies. Invertebrate larval abundances were lower for most taxa studied in the non-perturbed zone and northern time-series station. Significant differences (P < 0.001) of invertebrate larval abundance between the two zones sampled were found. Decapod larvae were the most abundant larval group in both zones. Stations located in eddy structures presented the highest values of larval densities. Specifically, the larvae collected at Station 18, located in the core of an anticyclonic eddy, represented 60±18% of total larvae collected in the south transect. Finally, our results suggest that eddies, mainly anticyclonic eddies, act as a strong larval retention zone south of the islands, and that there is a local northward transport from the Canary Islands.

scholarly journals Introduction

2018 ◽  
Vol 24 (2) ◽  
pp. 6
Author(s):  
Annemiek Richters
Keyword(s):  
Human Rights ◽  
Sexual Violence ◽  
Empirical Evidence ◽  
Limited Information ◽  
Long Term Effects ◽  
The South ◽  
Community Based ◽  
The North ◽  
Short And Long Term

It is generally known that during the 100 days of genocide against the Tutsi in Rwanda in 1994, sexual violence was committed on an unprecedented scale. Many women were first raped and then killed. With a certain degree of probability, the majority of Tutsi women who survived had been raped. Limited information is available regarding the experiences of these women. However, there is enough empirical evidence provided in human rights accounts and research reports substantiating that these women were exposed to unimaginable horror, which for the majority of them had a range of devastating short and long term effects. The programme of community-based sociotherapy was implemented in 2005 in the north of Rwanda in what was previously known as Byumba province, and subsequently in 2008 in Bugesera district in the south-east, one of the epicentres of the genocide.      

scholarly journals Géologie d'un secteur situé entre les fjords de Sermiligârssuk et Arsuk, (SW du Groenland)

1971 ◽  
Vol 32 ◽  
pp. 1-53
Author(s):  
L Bonnard
Keyword(s):  
Dyke Swarm ◽  
Tectonic Deformation ◽  
The South ◽  
Variable Intensity ◽  
The North ◽  
Two Generations ◽  
Arctic Conditions ◽  
Recent Origin ◽  
Intense Deformation ◽  
Mutual Relations

South-west Greenland belongs to the Precambrian shield; it is buiIt up of metamorphic, eruptive and, to a lesser extent, sedimentary rocks. The chronology of these formations and their structural relations are now fairly well established and are referred to three periods - pre-Ketilidian, Ketilidian and Gardar. Important unconformities separate the rocks of these divisions at the type localities. The greater part of the rocks occurring in the region mapped by the author belong to the pre-Ketilidian; these are migmatites - quantitatively the most important, ultramafic rocks, and metadolerites in various stages of alteration. The Ketilidian period was marked by local tectonic movements, metamorphism and the intrusion of small granitic bodies; the Ketilidian supracrustal succession lies immediately to the east of the area under consideration. The Gardar period has left its imprint in the form of widespread fractures and a dyke swarm composed mainly of dolerites and trachytes. The migmatites are predominantly gneisses, homogeneous and nebulitic in the north, banded and veined in the south. AlI the gneisses have a granodioritic or quartz-dioritic composition. Small masses of granite and sorne lenses of gabbro-anorthosite make up the remainder of the migmatite area, which structurally consists of a succession of domes and synclines with axes oriented in a general NW-SE direction with a culmination in the region of Dubletsø. The migmatite complex was probably derived from pelitic and arkosic sediments; it is the product of the metamorphism, migmatisation and intense deformation which marked the pre-Ketilidian. The ultrabasic bodies appear as small bodies within the migmatites: they are classified as steatites, serpentinites and actinolitites, the mutual relations of which form the subject of various hypotheses; it is probable that there exist two generations of ultrabasics separated by a phase of folding and migmatisation. The pre-Ketilidian metadolerites (like the later Gardar dykes) trend for the most part NE-SW. In the southern part of the area they are almost totally recrystallised due to later (presumably Ketilidian) metamorphism. The Ketilidian activity in the area was characterised by a metamorphism of variable intensity, most marked in the south-east of the area where it accompanied tectonic deformation. Dykes of microgranite and sorne small granitic and microdioritic bodies also belong to this period. The Gardar dyke complex comprises rare lamprophyres, trachytes and above all very numerous dolerites of which it is possible to distinguish several generations on the basis of intersections and microscopic characters. The fracturing and wrench-faulting described are also of Gardar age. FinalIy, within·the area many features of Quaternary and recent origin may be seen; these are the result of glaciation and the present arctic conditions.

Long-term Cyclic Variations of Prominences, Green and Red Coronae over Solar Cycles

2000 ◽  
Vol 179 ◽  
pp. 201-204
Author(s):  
Vojtech Rušin ◽  
Milan Minarovjech ◽  
Milan Rybanský
Keyword(s):  
Emission Lines ◽  
High Latitudes ◽  
Green Line ◽  
Solar Cycles ◽  
The South ◽  
Coronal Emission ◽  
Local Maxima ◽  
The North ◽  
Cyclic Variations

AbstractLong-term cyclic variations in the distribution of prominences and intensities of green (530.3 nm) and red (637.4 nm) coronal emission lines over solar cycles 18–23 are presented. Polar prominence branches will reach the poles at different epochs in cycle 23: the north branch at the beginning in 2002 and the south branch a year later (2003), respectively. The local maxima of intensities in the green line show both poleward- and equatorward-migrating branches. The poleward branches will reach the poles around cycle maxima like prominences, while the equatorward branches show a duration of 18 years and will end in cycle minima (2007). The red corona shows mostly equatorward branches. The possibility that these branches begin to develop at high latitudes in the preceding cycles cannot be excluded.

SEM and TEM observations of sperm development in the testis of the freshwater fish Oreochromis mossambicus

1990 ◽  
Vol 48 (3) ◽  
pp. 58-59
Author(s):  
Daryl A. Cornish ◽  
George L. Smit
Keyword(s):  
Morphological Characteristics ◽  
Oreochromis Mossambicus ◽  
Breeding Cycle ◽  
Limited Information ◽  
North West ◽  
The North ◽  
Sem And Tem ◽  
Sperm Development ◽  
Ultrastructural Characteristics ◽  
The University

Oreochromis mossambicus is currently receiving much attention as a candidater species for aquaculture programs within Southern Africa. This has stimulated interest in its breeding cycle as well as the morphological characteristics of the gonads. Limited information is available on SEM and TEM observations of the male gonads. It is known that the testis of O. mossambicus is a paired, intra-abdominal structure of the lobular type, although further details of its characteristics are not known. Current investigations have shown that spermatids reach full maturity some two months after the female becomes gravid. Throughout the year, the testes contain spermatids at various stages of development although spermiogenesis appears to be maximal during November when spawning occurs. This paper describes the morphological and ultrastructural characteristics of the testes and spermatids.Specimens of this fish were collected at Syferkuil Dam, 8 km north- west of the University of the North over a twelve month period, sacrificed and the testes excised.

US and Russian policies and strategies in the Middle East: Iraq and Syria as a model

2019 ◽  
pp. 220
Author(s):  
Esraa Aladdin Noori ◽  
Nasser Zain AlAbidine Ahmed
Keyword(s):  
Middle East ◽  
East Asia ◽  
Balance Of Power ◽  
Western World ◽  
International Conflicts ◽  
The South ◽  
The West ◽  
The North ◽  
East Region ◽  
Middle East Region

The Russian-American relations have undergone many stages of conflict and competition over cooperation that have left their mark on the international balance of power in the Middle East. The Iraqi and Syrian crises are a detailed development in the Middle East region. The Middle East region has allowed some regional and international conflicts to intensify, with the expansion of the geopolitical circle, which, if applied strategically to the Middle East region, covers the area between Afghanistan and East Asia, From the north to the Maghreb to the west and to the Sudan and the Greater Sahara to the south, its strategic importance will seem clear. It is the main lifeline of the Western world.

Depositional Environment Drive as Overpressure Generation: Study Case in “Gap” Field, North West Java Basin

2020 ◽  
Author(s):  
A., C. Prasetyo
Keyword(s):  
Clay Mineral ◽  
Depositional Environment ◽  
Mineral Content ◽  
Hydrocarbon Generation ◽  
Well Test ◽  
Burial History ◽  
The South ◽  
North West ◽  
The North ◽  
Geological Processes

Overpressure existence represents a geological hazard; therefore, an accurate pore pressure prediction is critical for well planning and drilling procedures, etc. Overpressure is a geological phenomenon usually generated by two mechanisms, loading (disequilibrium compaction) and unloading mechanisms (diagenesis and hydrocarbon generation) and they are all geological processes. This research was conducted based on analytical and descriptive methods integrated with well data including wireline log, laboratory test and well test data. This research was conducted based on quantitative estimate of pore pressures using the Eaton Method. The stages are determining shale intervals with GR logs, calculating vertical stress/overburden stress values, determining normal compaction trends, making cross plots of sonic logs against density logs, calculating geothermal gradients, analyzing hydrocarbon maturity, and calculating sedimentation rates with burial history. The research conducted an analysis method on the distribution of clay mineral composition to determine depositional environment and its relationship to overpressure. The wells include GAP-01, GAP-02, GAP-03, and GAP-04 which has an overpressure zone range at depth 8501-10988 ft. The pressure value within the 4 wells has a range between 4358-7451 Psi. Overpressure mechanism in the GAP field is caused by non-loading mechanism (clay mineral diagenesis and hydrocarbon maturation). Overpressure distribution is controlled by its stratigraphy. Therefore, it is possible overpressure is spread quite broadly, especially in the low morphology of the “GAP” Field. This relates to the delta depositional environment with thick shale. Based on clay minerals distribution, the northern part (GAP 02 & 03) has more clay mineral content compared to the south and this can be interpreted increasingly towards sea (low energy regime) and facies turned into pro-delta. Overpressure might be found shallower in the north than the south due to higher clay mineral content present to the north.

Observed seasonal regimes of North-South Atlantic Ocean interbasin exchange

2019 ◽  
Author(s):  
Hamed D. Ibrahim
Keyword(s):  
North Atlantic ◽  
Climate Models ◽  
South Atlantic ◽  
Meridional Overturning Circulation ◽  
Volume Flux ◽  
The South ◽  
The North ◽  
Basin Scale ◽  
Interbasin Exchange ◽  
North And South

North and South Atlantic lateral volume exchange is a key component of the Atlantic Meridional Overturning Circulation (AMOC) embedded in Earth’s climate. Northward AMOC heat transport within this exchange mitigates the large heat loss to the atmosphere in the northern North Atlantic. Because of inadequate climate data, observational basin-scale studies of net interbasin exchange between the North and South Atlantic have been limited. Here ten independent climate datasets, five satellite-derived and five analyses, are synthesized to show that North and South Atlantic climatological net lateral volume exchange is partitioned into two seasonal regimes. From late-May to late-November, net lateral volume flux is from the North to the South Atlantic; whereas from late-November to late-May, net lateral volume flux is from the South to the North Atlantic. This climatological characterization offers a framework for assessing seasonal variations in these basins and provides a constraint for climate models that simulate AMOC dynamics.

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