scholarly journals Estimating the timescale of fluvial response to anthropogenic disturbance using two generations of dams on the South River, Massachusetts, USA

2020 ◽  
Vol 45 (10) ◽  
pp. 2380-2393 ◽  
Author(s):  
Samantha Dow ◽  
Noah P. Snyder ◽  
William B. Ouimet ◽  
Anna M. Martini ◽  
Brian Yellen ◽  
...  
Keyword(s):  
Anthropogenic Disturbance ◽  
The South ◽  
Two Generations ◽  
Fluvial Response

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.

Voices from the South

2020 ◽  
pp. 155-186
Author(s):  
Gaetana Marrone
Keyword(s):  
Political Instability ◽  
Gabriel Garcia Marquez ◽  
Factory Worker ◽  
The South ◽  
The Past ◽  
Two Generations

In his adaptation of Carlo Levi's Cristo si é fermato a Eboli (Christ Stopped at Eboli, 1979), Rosi continues to confront the problems of the South—emigration, cultural marginalization, poverty—while reclaiming its rich, forgotten culture. The film signals a shift of Rosi's style, later evident in the slow-paced Cronaca di una morte annunciata (Chronicle of a Death Foretold, 1987), an epic adaptation of Gabriel García Márquez' 1981 novel that, like Cristo, is structured as an archetypal journey back to the past. In Tre fratelli (Three Brothers, 1981), Italy's chronic political instability is reflected in the tale of a self-assured judge, an idealistic teacher, and an angry factory worker and labor organizer. Summoned home for their mother's funeral, the brothers revisit their peasant roots, confront their present, and imagine their future. The film's concluding wide shot, which unites two generations, indicates Rosi's return to ahistorical values.

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

The Way of the Exile

2020 ◽  
pp. 91-107
Keyword(s):  
The South ◽  
Physical Separation ◽  
Two Generations ◽  
The Way

In this lecture Woodward examines the consequences of self-exile for two generations of southern dissenters. While in exile, they continued to think and speak of themselves as Southerners. They were preoccupied with Southern problems; they wrote largely for a Southern audience; and they could only realize their vision in the South. Ironically, their books and pamphlets were outlawed and systematically suppressed in the region. As outcasts, the exiles found acceptance only among abolitionist cliques, who were often at war with themselves. Physical separation from their families was the least of their troubles. Ideological alienation proved to be far more painful. In leaving the South, these dissenters forfeited their positions, connections, and relationships. They were never able to reconcile their choice to leave with their lingering loyalty to the region.

scholarly journals The Effects of Hypoxia and Anthropogenic Disturbance on the Distribution, Abundance and Recruitment of the Sea Cucumber Holothuria leucospilota at the Mouth of a Subtropical Bay, China

2021 ◽  
Vol 8 ◽  
Author(s):  
Zonghe Yu ◽  
Yingqiu Zhang ◽  
Lei Zhou ◽  
Hongyan Sun
Keyword(s):  
South China Sea ◽  
South China ◽  
Anthropogenic Disturbance ◽  
Sea Cucumber ◽  
Larval Settlement ◽  
Open Water ◽  
The South China Sea ◽  
Daya Bay ◽  
The South ◽  
China Sea

Despite the commercial importance of the sea cucumber Holothuria leucospilota increasing in recent years, little is known of its spatial distribution and ecology in the South China Sea. We investigate the distribution, abundance, and recruitment of H. leucospilota from 2017 to 2020 at two sites (S1 and S2) in Daya Bay, a typical subtropical bay which is strongly influenced by human activities in the South China Sea. We report hypoxia to drive H. leucospilota from deeper into shallower waters with higher DO concentrations at the mouth of Dapeng Cove in Daya Bay (S1), particularly during summer. Population size at S1 decreased by 90% from 2017 levels, before this area was opened to the public in 2018; recruitment was not observed by August (summer) of 2020. In contrast, in summers of 2017 and 2020, H. leucospilota abundance at S2, a protected open-water area, increased by 84%, and the proportion of small-sized (recently recruited) sea cucumber in the population increased by 20%. Severe summer hypoxia at S1 could negatively influence H. leucospilota spawning and larval settlement, which combined with depletion of broodstock because of fishing pressure and/or hypoxia-induced mortality, could inhibit recruitment. In contrast, higher DO concentrations and abundant broodstock during summer (the breeding season) favoured recruitment of H. leucospilota at S2. Overall, hypoxia and anthropogenic disturbance impede recovery of H. leucospilota at S1, while at the protected S2, larvae may be released to settle in nearby areas. It is imperative to develop a better understanding of the biology, ecology and conservation of tropical sea cucumbers in China.

scholarly journals Multiple stages of serpentinization in mantle derived peridotites of the South Armorican Variscan suture zone

2021 ◽  
Author(s):  
Geoffrey Aertgeerts ◽  
Didier Lahondère ◽  
Christophe Monnier ◽  
Jean-Pierre Lorand
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
High Rate ◽  
Variscan Orogeny ◽  
Fluid Composition ◽  
The South ◽  
Mantle Peridotites ◽  
Two Generations ◽  
High Temperature Stage ◽  
Polycrystalline Structures

<p>South Armorican mantle peridotites represent a great diversity of protoliths from supra-subduction zone to arc-fore arc ophiolites. In this study, we investigate the serpentinization of these protoliths. Numerous samples were collected in five different units, which represent ophiolitic dismembered pieces (Ty-Lan Peridotites (TLP) from the Audierne Complex, and Pont de Barel Peridotites (PBP), Folies Siffait Peridotites (FSP), l’Orgerais Peridotites (LOP) and Drain Peridotites (DP) from the Champtoceaux Complex). Field and microscopic observations together with Raman spectroscopy and electronic microprobe analysis (EMPA) allowed to identify several stages of serpentinization. All samples display a high rate of serpentinization, up to 80-90 %. Primary assemblage is represented by spinel (TLP, PBP, DP and LOP), olivine (TLP and FSP) and Ti-poor or Cr-rich pargasite (TLP and PBP). In all the samples, lizardite from olivine and bastites from pyroxene and amphibole characterize the first stage of serpentinization. It is associated with magnetite crystallization. No Al-rich lizardite meshe is identified by EMPA suggesting a low temperature (< 340°C) event. This serpentinization is followed by two generations of veins (V1 and V2). The V1 are Al-poor lizardite shear veins and crack-seal chrysotile veins characterize the V2. In PBP, microprobe mapping shows that V2 displays heterogeneous chemical chrysotile composition with significant variations of Al, Fe and Mg contents, suggesting metasomatism and/or variation of fluid composition during serpentinization. All these observations are closely similar to those of oceanic serpentinized peridotites. In the TLP, we identified a second stage of serpentinization characterized by antigorite after lizardite suggesting a high temperature event. In the OP, antigorite after lizardite was also identified. However, compared to the TLP ones, LOP antigorite is related to ductile (i.e., ultramylonite) deformations. This clearly indicates a high temperature stage of serpentinization (up to 500 °C). Furthermore, LOP ultramylonitized samples display one more chrysotile veins generation (V3) characterized by three distinct vein networks. The first one (V3a) is a crack-seal type vein network opened parallel to the main foliation. The second one (V3b) is perpendicular to the first one, whereas the third one (V3c) corresponds to tension gashes connected to C’ plans. This latter is perpendicular to V3a and V3b networks. The mylonitic foliation of LOP is similar to the surrounding micaschists schistosity, suggesting an orogenic high temperature stage of serpentinization. In the FSP, σ-type polycrystalline structures were identified. Lizardite meshes are progressively transposed and recrystallized into the foliation plan. This stage is associated with the crystallization of chlorite after tremolite, suggesting a retrograde stage of serpentinization during serpentinites exhumation. Finally, despite a great diversity of mantle-derived protoliths, our study shows that South-Armorican peridotites recorded a similar first low temperature oceanic stage of serpentinization. According to the Variscan history, it could have started during the Cambro-Ordovician for TLP, and during the Late Devonian for PBP, DP, LOP, FSP. Furthermore, some of these peridotites also recorded an orogenic serpentinization (LOP and FLP). Such observations provide new constraints that could be useful to a better understanding of the tectonometamorphic evolution of the South Armorican suture zones during the Variscan orogeny. </p>

Genetic diversity of the Fusarium oxysporum complex isolated from the grassland biome of South Africa.

2020 ◽  
Author(s):  
Mudzuli Mavhunga ◽  
Thiambi Grace Kwinda ◽  
Brett Anthony Summerell ◽  
Eduard Venter ◽  
Adriaana Jacobs
Keyword(s):  
South Africa ◽  
Genetic Diversity ◽  
Fusarium Oxysporum ◽  
South African ◽  
Anthropogenic Disturbance ◽  
Elongation Factor ◽  
Sub Saharan Africa ◽  
Anthropogenic Activity ◽  
The South ◽  
Grassland Biome

The genetic diversity of pathogenic members of the Fusarium oxysporum species complex (FOSC) has been intensively studied worldwide, yet strains occurring from native soils with low anthropogenic disturbance remain poorly understood. This study focused on 355 F. oxysporum isolates from soils with low anthropogenic activity obtained from the grassland biome of South Africa. Analysis of the translation elongation factor 1-alpha (tef-1α) gene revealed high levels of sequence type (ST) diversity within the soil population in comparison to the global dataset. Phylogenetic relationships of the South African isolates revealed that only four nested within FOSC Clade 1. This is the first report of members of the basal clade recovered from ecosystems with low anthropogenic disturbance from Sub-Saharan Africa. The remaining strains nested within Clades 2 to 5. This study contributes significantly to our understanding of the distribution of the FOSC in natural systems as we show that FOSC populations in the South African grassland biome are genetically diverse. This fills in our knowledge gap as previous studies reported only on the occurrence and diversity of the FOSC isolated from plant debris in South Africa. This is the first comprehensive survey of fusaria from grassland soils with low anthropogenic disturbance in South Africa.

“We’re what we are because of the Past”: History, Memory, Nostalgia, and Identity in Walter Sullivan’s The Long, Long Love

2014 ◽  
Vol 46 (2) ◽  
pp. 17-36
Author(s):  
Tanfer Emin Tune
Keyword(s):  
Civil War ◽  
New South ◽  
Past History ◽  
Professional Life ◽  
The South ◽  
History And Memory ◽  
The Past ◽  
Two Generations ◽  
American Intellectual ◽  
Vanderbilt University

Walter Sullivan (1924–2006), a Nashville, Tennessee native who spent most of his academic and professional life at Vanderbilt University, is generally considered by critics as a literary descendent of the first two generations of Fugitive-Agrarians and the Southern Renaissance to which they belong. This essay seeks to position Sullivan’s second, largely forgotten novel, The Long, Long Love as part of the postagrarian, post-Renaissance, postmodern, and post-southern American intellectual reevaluation of the South that questions tradition through an assertion of “pro–New South, pro–urban, and pro–capitalist” values and thoroughly reconsiders Civil War “truths,” myths, history, and memory.

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.

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