scholarly journals Infection Levels of the Microsporidium Larssoniella duplicati in Populations of the Invasive Bark Beetle Ips duplicatus: From Native to New Outbreak Areas

Forests ◽  
2019 ◽  
Vol 10 (2) ◽  
pp. 131 ◽  
Author(s):  
Soňa Zimová ◽  
Karolina Resnerová ◽  
Hana Vanická ◽  
Jakub Horák ◽  
Jiří Trombik ◽  
...  
Keyword(s):  
Picea Abies ◽  
Bark Beetle ◽  
The South ◽  
Infection Level ◽  
The North ◽  
Ips Duplicatus ◽  
Specific Pathogen ◽  
Outbreak Areas ◽  
Study Sites ◽  
A Site

The microsporidium Larssoniella duplicati (Weiser, Holuša, Žižka, 2006) is a specific pathogen of the bark beetle Ips duplicatus (C.R. Sahlberg, 1836), which is a serious pest of Norway spruce (Picea abies (L.) H. Karst) in Europe. From 2011 to 2016, infection levels of L. duplicati and other pathogens in I. duplicatus populations were assessed along a gradient, ranging from areas in the north, where the beetle is native, to areas in the south, where the beetle has only recently invaded. The 21 study sites ranged in altitude from 229 to 1009 m a.s.l. We found that pathogen infection levels in I. duplicatus populations decreased from the native areas in the north to the new areas of beetle expansion in the south. We also found that pathogen level increased with altitude. The L. duplicati infection levels were not associated with the infection levels of other beetle natural enemies. The infection level decreased with the length of time of beetle establishment in an area. The infection level increased with the number of beetles trapped and dissected at a site.

Communication and the Global South

2018 ◽  
Author(s):  
Doug Ashwell ◽  
Stephen M. Croucher
Keyword(s):  
Academic Research ◽  
Global South ◽  
Press Freedom ◽  
Alternative Development ◽  
The South ◽  
Cultural Economic ◽  
The North ◽  
Global North ◽  
A Site ◽  
Development Trajectories

The Global South–North divide has been conceptualized in political, cultural, economic, and developmental terms. When conceptualizing this divide, issues of economic growth/progress, technology, political and press freedom, and industrialization have all been used as indicators to delineate between the “North” and the “South.” The North has traditionally been seen as more economically, technologically, politically, and socially developed, as well as more industrialized and having more press freedom, for example; the South has been linked with poverty, disease, political tyranny, and overall lack of development. This conceptualization privileges development efforts in the Global South based on democratic government, capitalist economic structures with their attendant neoliberal agenda and processes of globalization. This negative view of the South is a site of contest with people of the South offering alternative and more positive views of the situation in the South and alternatives to globalization strategies. While there may be some identifiable difference between some of the countries in the identified Global South and Global North, globalization (economic, political, technological, etc.) is changing how the very Global South–North divide is understood. To best understand the implications of this divide, and the inequalities that it perpetuates, we scrutinize the Global South, detailing the background of the term “Global South,” and examine the effect of globalization upon subaltern groups in the Global South. We also discuss how academic research using frameworks of the Global North can exacerbate the problems faced by subaltern groups rather than offer them alternative development trajectories by empowering such groups to represent themselves and their own development needs. The culture-centred approach to such research is offered as alternative to overcome such problems. The terms usage in the communication discipline is also explained and the complexity of the term and its future is explored.

Comparative Study of Airborne Pollen from the Northern to the Southern of Tunisia

2019 ◽  
pp. 1-8 ◽  
Author(s):  
S. Hadj Hamda ◽  
A. Ben Dhiab ◽  
M. Msallem ◽  
A. Larbi
Keyword(s):  
Crop Production ◽  
Airborne Pollen ◽  
Flowering Phenology ◽  
Plant Distribution ◽  
The South ◽  
Pollen Type ◽  
The North ◽  
Flowering Season ◽  
Pollen Types ◽  
Study Sites

Aerobiology is a multidisciplinary science dealing with biological particles in the atmosphere generated by natural activities during flowering season. Airborne pollen is now the main studied biological structure which is used as a reliable tool to study plant phenology, plant distribution changes and prediction of crop production. The main aims of this work is to determine the distribution of the different spring flowering species from the North to the South of Tunisia and to establish the pollen spectrum of three regions Mornag (North), Menzel M’hiri (Centre) and Chaal (South) in 2017. Airborne pollen data were collected using three volumetric Hirst-type spore traps placed in Mornag (36°39N; 10°16E), Menzel M’hiri (35°38N; 10°41E) and Chaal (34°34N; 10°19E) during olive flowering season. The highest pollen index was recorded in the north (Mornag, 6487.1) corresponding mainly to 18 different pollen types emitted by anemophilous species with an important presence of Cupressus pollen type having the highest contribution. Lower pollen amounts were recorded in Menzel M’hiri (5983.8) and Chaal (925.3). Olea eurpoeae was the most presented pollen type in these regions. However comparing the different study sites we can note a large distribution of some taxa from north to the south. The main common taxa were Olea europaea, Cupressaceae, Poaceae and Amaranhaceae. Their atmospheric concentrations varied also between the regions. Individual pollen index showed a sharp heterogeneity between the taxa in the same region in one hand and between the study sites in the other hand, thus a statistical analysis was performed to define the main group of taxa according to their individual pollen index. Flowering phenology of the main common taxa was also established.

Part I. Neolithic Mycenae

1957 ◽  
Vol 52 ◽  
pp. 195-196 ◽  
Author(s):  
A. J. B. Wace
Keyword(s):  
Bronze Age ◽  
Recent Work ◽  
Early Bronze Age ◽  
The South ◽  
North West ◽  
The North ◽  
Fabric Hand ◽  
A Site

Stamatakes's excavations in the Grave Circle area revealed, although it was not recognized until much later, that Mycenae had been inhabited in the Early Bronze Age, the Early Helladic Period. This was confirmed by subsequent researches which produced Early Helladic material from the foot of the Ramp, outside the Grave Circle, beneath the South House and below the Palace. Now the recent work of Dr. Papademetriou and ourselves has yielded fresh evidence. He has found more E.H. material in Schliemann's Grave Circle and some possible Neolithic sherds as well. In the area of the Prehistoric Cemetery outside the Cyclopean walls to the north-west of the Lion Gate we have found in a mixed unstratified layer at the eastern foot of the mound or tumulus which covered the dome of the ‘Tomb of Aegisthus’ many fragments of E.H. pottery, both decorated and plain. Since the plain E.H. ware found is of a simple, thickish fabric hand-polished and usually of a dull red or of a mud colour, we had at times wondered whether some of these fragments might not almost be classed as Neolithic. This was especially so in the case of some of the fragments from the lowest strata at the foot of the Ramp. Unfortunately these fragments were lost during the war in the Nauplia Museum and cannot now be checked.The discovery of Neolithic B pottery at the Argive Heraeum, and still more recently Dr. Caskey's most successful excavations at Lerna, encouraged us in the idea that a site like Mycenae was probably inhabited in Neolithic times also. Since the Early Helladic material is not stratified, except in areas like the foot of the Ramp or below the South House, it was hardly to be expected that Neolithic remains, if found, would be stratified. It is always possible, however, that some part of the site, not yet explored, may have escaped later disturbance or overbuilding. We have therefore now paid particular attention to the unstratified debris found above the Prehistoric Cemetery at the eastern foot of the Aegisthus mound. Among this we have found two sherds which are in our opinion almost certainly Neolithic.

scholarly journals Variation of Vitellaria paradoxa phenophases along the north-south gradient in Mali

1970 ◽  
pp. 08-16
Author(s):  
Bokary Allaye Kelly ◽  
Mahesh Poudyal ◽  
Jean-Marc Bouvet
Keyword(s):  
Average Length ◽  
Abiotic Factors ◽  
Permanent Plots ◽  
Future Research ◽  
Vitellaria Paradoxa ◽  
The South ◽  
The North ◽  
Study Sites ◽  
Shea Tree ◽  
Research Challenge

We monitored flowering, fruiting and leafing of Vitellaria paradoxa (shea tree) along the north–south gradient in Mali (West Africa), using three study sites for a period of three years. In each site, adult shea trees were marked and monitored in permanent plots of both field and fallow stands. The chronology of phenophases and their mean length as well as flowering and fruiting were assessed. Our data revealed significant variation according to site and stand. The onset of events starts earlier in the south than in the centre or north, but the period covered by events was almost the same for all sites (3 to 6 months for flowering; 5 to 6 months for fruiting; and 2 to 4 months before full leafing).Flowering and fruiting were more regular in the south, but often as high in the north, with an almost similar trend in both fields and fallows. In the centre, flowering was also high in fields as well as in fallows, while the fruiting was medium to high. We also observed variations in the mean length of phenological events in study sites and stands. Sites in the south showed the highest average length of flowering and leafing (76 days and 44 days, respectively), while the central site showed the greatest length of mean fruiting (110 days).  We observed a significant site*stand interaction and noticeable variation over the years. Our study indicates that phenological events of shea tree could be influenced by several interacting biotic and abiotic factors. A future research challenge in shea phenology would be to discriminate these factors and thus help sustainable management of shea tree parklands.

scholarly journals Hybrid data-model-based mapping of soil thickness in a mountainous watershed

2021 ◽  
Author(s):  
Qina Yan ◽  
Haruko Wainwright ◽  
Baptiste Dafflon ◽  
Sebastian Uhlemann ◽  
Carl I. Steefel ◽  
...  
Keyword(s):  
Hybrid Model ◽  
Spatial Resolution ◽  
Soil Layer ◽  
The South ◽  
Soil Thickness ◽  
The North ◽  
Soil Erosion Rate ◽  
East River ◽  
Thickness Prediction ◽  
Study Sites

Abstract. Soil thickness plays a central role in the interactions between vegetation, soils, and topography where it controls the retention and release of water, carbon, nitrogen, and metals. However, mapping soil thickness, here defined as the mobile regolith layer, at high spatial resolution remains challenging. Here, we develop a hybrid model that combines a process-based model and empirical relationships to estimate the spatial heterogeneity of soil thickness with fine spatial resolution (0.5 m). We apply this model to two examples of hillslopes (south-facing and north-facing, respectively) in the East River Watershed in Colorado that validates the effectiveness of the model. Two independent measurement methods – auger and cone penetrometer – are used to sample soil thickness at 78 locations to calibrate the local value of unconstrained parameters within the hybrid model. Sensitivity analysis using the hybrid model reveals that the diffusion coefficient used in hillslope diffusion modelling has the largest sensitivity among all input parameters. In addition, our results from both sampling and modeling show that, in general, the north-facing hillslope has a deeper soil layer than the south-facing hillslope. By comparing the soil thickness estimated between a machine learning approach and this hybrid model, the hybrid model provides higher accuracy and requires less sampling data. Modeling results further reveal that the south-facing hillslope has a slightly faster surface soil erosion rate and soil production rate than the north-facing hillslope, which suggests that the relatively less dense vegetation cover and drier surface soils on the south-facing slopes may influence soil characteristics. With only seven parameters for calibration, this hybrid model can provide a realistic soil thickness map at other study sites by with a relatively small amount of sampling dataset. Integrating process-based modeling and statistical analysis not only provides a thorough understanding of the fundamental mechanisms for soil thickness prediction, but integrates the strengths of both statistical approaches and process-based modeling approaches.

scholarly journals Excavations at Naukratis A. Site and Buildings

1899 ◽  
Vol 5 ◽  
pp. 26-46 ◽  
Author(s):  
D. G. Hogarth
Keyword(s):  
Hollow Heart ◽  
The South ◽  
North East ◽  
The North ◽  
A Site ◽  
Uncultivated Land

Mr. Ernest Gardner, summing up in 1889 the results of the excavations at Naukratis which Mr. Flinders Petrie had begun in 1884, was of opinion that something still remained to be done on the site. This opinion was shared by Mr. Petrie and has been expressed by him more than once, when Greek remains in Egypt were under discussion. A further campaign, therefore, has long been contemplated; and when I heard late in 1898 that very serious encroachments were being made upon the mounds of Gaif, it seemed that it was time to act. Paying a flying visit to the place in December, I found that, compared with Mr. Petrie's map of fourteen years before, the Mounds showed a greatly changed appearance. The “Great Temenos” at the south end had become a cornfield: the “Arab village” shown in the map on the north-east edge of the mound was now divided from the uncultivated land by a broad belt of green, which in the east centre had been pushed far out into the hollow heart of the site by an artificial embankment twelve to fifteen feet high.

Early seedling establishment of Picea abies in small forest gaps in the Swiss Alps

1998 ◽  
Vol 28 (4) ◽  
pp. 626-639 ◽  
Author(s):  
Peter Brang
Keyword(s):  
Picea Abies ◽  
Swiss Alps ◽  
North Slope ◽  
Organic Layer ◽  
The South ◽  
Direct Sunlight ◽  
The North ◽  
South Slope ◽  
Early Seedling ◽  
Small Forest

Early seedling establishment of Picea abies (L.) Karst. in small forest gaps was studied in drier, subalpine P. abies ecosystems in the Swiss Alps. Study sites were on steep south and north slopes. Average gap size was 15 m x 20 m on the south slope and 15 m x 70 m on the north slope. Sowing trials established on different microsites were observed for 2 or 3 years. Direct sunlight was assessed with hemispherical photography. Emergence was better on the north slope than on the south slope. On the south slope, emergence was higher on the mineral soil than on the organic layer and was negatively associated with direct sunlight, especially during the noon period. On both slopes, drought due to rainfall interception at the gap edge negatively affected emergence. The limiting factor for survival and growth on the south slope was drought (on the organic layer), whereas on the north slope lack of direct radiation and pathogenic fungi developing in the snowpack were limiting. The early regeneration niche on the south slope was narrower than on the north slope.

A Site at Stump Cross, near Grassington, Yorkshire, and the Age of the Pennine Microlithic Industry

1957 ◽  
Vol 22 ◽  
pp. 23-28 ◽  
Author(s):  
D. Walker
Keyword(s):  
Solid Rock ◽  
Calluna Vulgaris ◽  
Eriophorum Vaginatum ◽  
The South ◽  
North West ◽  
The North ◽  
A Site ◽  
Humified Peat

The site described in this paper lies on the Yorkshire Pennines, slightly over 1,200 feet O.D., half a mile north-west of Stump Cross Cavern and five miles east of Grassington (Nat. Grid 082640). The solid rock there is an eastward extension of the Great Scar Limestone, pitted by numerous swallow holes and clothed by a thin and intermittent mantle of clayey glacial drift. Only a hundred yards to the north and half a mile to the south-east of the site the Millstone Grit replaces the limestone at the surface. In the vicinity of the site the vegetation is dominated by Calluna vulgaris and Eriophorum vaginatum growing over a podsol or a shallow, highly humified, peat.

The Global South Atlantic

2017 ◽  
Keyword(s):  
Social Relations ◽  
Global South ◽  
South Atlantic ◽  
Regional Studies ◽  
Political Movements ◽  
The South ◽  
Atlantic Studies ◽  
The North ◽  
The Caribbean ◽  
A Site

Despite the rise in transatlantic, oceanic, hemispheric, and regional studies that followed postcolonial and Third World studies in pursuing new frameworks and methods for examining South-South connections, the South Atlantic has not yet emerged as a “site” that captures the general imagination or the scholarly attention it deserves—particularly in literature and cultural studies. The Global South Atlantic traces literary exchanges, socio-historical linkages, networks of communication and exchange, and overlapping investments (financial, political, social, cultural, and libidinal) among Africa, Latin America, and the Caribbean that remain largely invisible to an Atlantic Studies still primarily inclined toward the North. Bringing together scholars working in Lusophone, Francophone, Hispanophone, and Anglophone contexts, as well as researchers working across other languages (such as Arabic) that are important components of a Global South Atlantic, the chapters in this volume demonstrate many important ways in which people, governments, political movements, social imaginaries, cultural artefacts, goods, and markets do (and sometimes do not) cross the South Atlantic. Combined, they help to reveal complex and intermeshed webs of cultural, material, and social relations that begin to make visible a multi-textured version of a South Atlantic system that is neither singular nor stable. As a region made up of multiple intersecting regions, as a vision made up of complementary and competing visions, the South Atlantic can only be understood comparatively. Exploring the Atlantic as an effect of structures of power and knowledge that issue from the Global South (as much as from Europe and North America), The Global South Atlantic seeks to rebalance global literary studies by shifting perspectives on transatlantic flows and charting overlooked routes of comparison.

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.

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