881 resultados para MESSINIAN SALINITY CRISIS
Resumo:
This study analyses British military planning and actions during the Suez Crisis in 1956. It seeks to find military reasons for the change of concepts during the planning and compares these reasons with the tactical doctrines of the time. The thesis takes extensive advantage of military documents preserved in the National Archives, London. In order to expand the understanding of the exchange of views during the planning process, the private papers of high ranking military officials have also been consulted. French military documents preserved in the Service Historique de la Defence, Paris, have provided an important point of comparison. The Suez Crisis caught the British armed forces in the middle of a transition phase. The main objective of the armed forces was to establish a credible deterrence against the Soviet Union. However, due to overseas commitments the Middle East playing a paramount role because of its economic importance the armed forces were compelled to also prepare for Limited War and the Cold War. The armed forces were not fully prepared to meet this demand. The Middle Eastern garrison was being re-organised after the withdrawal from the Canal Base and the concept for a strategic reserve was unimplemented. The tactical doctrines of the time were based on experiences from the Second World War. As a result, the British view of amphibious operations and the subsequent campaigns emphasised careful planning, mastery of the sea and the air, sufficient superiority in numbers and firepower, centralised command and extensive administrative preparations. The British military had realized that Nasser could nationalise the Suez Canal and prepared an outline plan to meet this contingency. Although the plan was nothing more than a concept, it was accepted as a basis for further planning when the Canal was nationalised at the end of July. This plan was short-lived. The nominated Task Force Commanders shifted the landing site from Port Said to Alexandria because it enabled faster expansion of the bridgehead. In addition, further operations towards Cairo the hub of Nasser s power would be easier to conduct. The operational concept can be described as being traditional and was in accordance with the amphibious warfare doctrine. This plan was completely changed at the beginning of September. Apparently, General Charles Keightley, the Commander-in-Chief, and the Chairman of the Chiefs of Staff Committee developed the idea of prolonged aerial operations. The essence of the concept was to break the Egyptian will to resist by attacking the oil facilities, the transportation system and the armed forces. This victory through air concept would be supported by carefully planned psychological operations. This concept was in accordance with the Royal Air Force doctrine, which promoted a bomber offensive against selected target categories. General Keightley s plan was accepted despite suspicions at every planning level. The Joint Planning Staff and the Task Force Commanders opposed the concept from the beginning to the end because of its unpredictability. There was no information that suggested the bombing would persuade the Egyptians to submit. This problem was worsened by the fact that British intelligence was unable to provide reliable strategic information. The Task Force Commanders, who were responsible for the tactical plans, were not able to change Keightley s mind, but the concept was expanded to include a traditional amphibious assault on Port Said due to their resistance. The bombing campaign was never tested as the Royal Air Force was denied authorisation to destroy the transportation and oil targets. The Chiefs of Staff and General Keightley were too slow to realise that the execution of the plan depended on the determination of the Prime Minister. However, poor health, a lack of American and domestic support and the indecisiveness of the military had ruined Eden s resolve. In the end, a very traditional amphibious assault, which was bound to succeed at the tactical level but fail at the strategic level, was launched against Port Said.
Resumo:
Whilst the topic of soil salinity has received a substantive research effort over the years, the accurate measurement and interpretation of salinity tolerance data remain problematic. The tolerance of four perennial grass species (non-halophytes) to sodium chloride (NaCl) dominated salinity was determined in a free-flowing sand culture system. Although the salinity tolerance of non-halophytes is often represented by the threshold salinity model (bent-stick model), none of the species in the current study displayed any observable salinity threshold. Further, the observed yield decrease was not linear as suggested by the model. On re-examination of earlier datasets, we conclude that the threshold salinity model does not adequately describe the physiological processes limiting growth of non-halophytes in saline soils. Therefore, the use of the threshold salinity model is not recommended for non-halophytes, but rather, a model which more accurately reflects the physiological response observed in these saline soils, such as an exponential regression curve.
Resumo:
The variability of the sea surface salinity (SSS) in the Indian Ocean is studied using a 100-year control simulation of the Community Climate System Model (CCSM 2.0). The monsoon-driven seasonal SSS pattern in the Indian Ocean, marked by low salinity in the east and high salinity in the west, is captured by the model. The model overestimates runoff int the Bay of Bengal due to higher rainfall over the Himalayan-Tibetan regions which drain into the Bay of Bengal through Ganga-Brahmaputra rivers. The outflow of low-salinity water from the Bay of Bengal is to strong in the model. Consequently, the model Indian Ocean SSS is about 1 less than that seen in the climatology. The seasonal Indian Ocean salt balance obtained from the model is consistent with the analysis from climatological data sets. During summer, the large freshwater input into the Bay of Bengal and its redistribution decide the spatial pattern of salinity tendency. During winter, horizontal advection is the dominant contributor to the tendency term. The interannual variability of the SSS in the Indian Ocean is about five times larger than that in coupled model simulations of the North Atlantic Ocean. Regions of large interannual standard deviations are located near river mouths in the Bay of Bengal and in the eastern equatorial Indian Ocean. Both freshwater input into the ocean and advection of this anomalous flux are responsible for the generation of these anomalies. The model simulates 20 significant Indian Ocean Dipole (IOD) events and during IOD years large salinity anomalies appear in the equatorial Indian Ocean. The anomalies exist as two zonal bands: negative salinity anomalies to the north of the equator and positive to the south. The SSS anomalies for the years in which IOD is not present and for ENSO years are much weaker than during IOD years. Significant interannual SSS anomalies appear in the Indian Ocean only during IOD years.
Resumo:
[Excerpt] It is projected that between 2001 and 2007, 47 percent of community college presidents will have left their positions. At a time when challenges are growing more complex, the senior administrators who typically moved into presidencies are also "aging out," leaving fewer qualified individuals in the pipeline. The Institute for Community College Development (ICCD), a partnership between the State University of New York (SUNY) and Cornell, was founded by a group of community college presidents to respond to this leadership crisis. ICCD has been part of ILR since 2001.
Resumo:
Interest in the development of aquaculture of the tropical spiny lobster, Panulirus ornatus, has increased markedly over the past 10 yr because of strong market demand and high prices. In Australia, economic conditions will necessitate that a semi-intensive approach be taken, possibly involving managed environmental conditions. Identification of optimal temperature and salinity levels will be necessary, and therefore two experiments were performed to examine these two parameters. Juvenile lobsters were grown in tanks at five temperatures (19, 22, 25, 28 and 31 C). Growth was significantly affected by temperature (P < 0.01), and maximal growth occurred at 25-31 C. Examination of the temperature effect on molt increment and intermolt period indicated that 27 C was the optimal temperature, at which molt increment was greatest and intermolt period the least. Temperature also had a significant (P < 0.01) positive effect on apparent feed intake (AFI). Juvenile lobsters were also exposed to four different salinities (20, 25, 30 and 35 ppt) over a period of 91 d. Significant differences (P < 0.01) were apparent for both survival and growth. Lowest survival occurred at 35 ppt which may be attributable to higher cannibalism at that salinity. Growth was highest at 35 ppt and progressively less at lower salinities. Although full marine salinity (35 ppt) will generate best performance of P. ornatus, its capacity to tolerate reduced salinity will provide greater opportunity to develop commercial aquaculture.
Resumo:
Salinity is an increasingly important issue in both rural and urban areas throughout much of Australia. The use of recycled/reclaimed water and other sources of poorer quality water to irrigate turf is also increasing. Hybrid Bermudagrass (Cynodon dactylon (L.) Pers. x C. transvaalensis Burtt Davey), together with the parent species C. dactylon, are amongst the most widely used warm-season turf grass groups. Twelve hybrid Bermudagrass genotypes and one accession each of Bermudagrass (C. dactylon), African Bermudagrass (C. transvaalensis) and seashore paspalum (Paspalum vaginatum Sw.) were grown in a glasshouse experiment with six different salinity treatments applied hydroponically through the irrigation water (ECW = <0.1, 6, 12, 18, 24 or 30 dSm-1) in a flood-and-drain system. Each pot was clipped progressively at 2-weekly intervals over the 12-week experimental period to determine dry matter production; leaf firing was rated visually on 3 occasions during the last 6 weeks of salinity treatment. At the end of the experiment, dry weights of roots and crowns below clipping height were also determined. Clipping yields declined sharply after about the first 6 weeks of salinity treatment, but then remained stable at substantially lower levels of dry matter production from weeks 8 to 12. Growth data over this final 4-week experimental period is therefore a more accurate guide to the relative salinity tolerance of the 15 entries than data from the preceding 8 weeks. Based on these data, the 12 hybrid Bermudagrass genotypes showed moderate salinity tolerance, with FloraDwarfM, 'Champion Dwarf', NovotekM and 'TifEagle' ranking as the most salt tolerant and 'Patriot', 'Santa Ana', 'Tifgreen' and TifSport M the least tolerant within the hybrid group. Nevertheless, Santa Ana, for example, maintained relatively strong root growth as salinity increased, and so may show better salt tolerance in practice than predicted from the growth data alone. The 12 hybrid Bermudagrasses and the single African Bermudagrass genotype were all ranked above FloraTeXM Bermudagrass in terms of salt tolerance. However, seashore paspalum, which is widely acknowledged as a halophytic species showing high salt tolerance, ranked well above all 14 Cynodon genotypes in terms of salinity tolerance.
Resumo:
This project built upon the successful outcomes of a previous project (TU02005) by adding to the database of salt tolerance among warm season turfgrass cultivars, through further hydroponic screening trials. Hydroponic screening trials focussed on new cultivars or cultivars that were not possible to cover in the time available under TU02005, including: 11 new cultivars of Paspalum vaginatum; 13 cultivars of Cynodon dactylon; six cultivars of Stenotaphrum secundatum; one accession of Cynodon transvaalensis; 12 Cynodon dactylon x transvaalensis hybrids; two cultivars of Sporobolus virginicus; five cultivars of Zoysia japonica; one cultivar of Z. macrantha, one common form of Z. tenuifolia and one Z. japonica x tenuifolia hybrid. The relative salinity tolerance of different turfgrasses is quantified in terms of their growth response to increasing levels of salinity, often defined by the salt level that equates to a 50% reduction in shoot yield, or alternatively the threshold salinity. The most salt tolerant species in these trials were Sporobolus virginicus and Paspalum vaginatum, consistent with the findings from TU02005 (Loch, Poulter et al. 2006). Cynodon dactylon showed the largest range in threshold values with some cultivars highly sensitive to salt, while others were tolerant to levels approaching that of the more halophytic grasses. Coupled with the observational and anecdotal evidence of high drought tolerance, this species and other intermediately tolerant species provide options for site specific situations in which soil salinity is coupled with additional challenges such as shade and high traffic conditions. By recognising the fact that a salt tolerant grass is not the complete solution to salinity problems, this project has been able to further investigate sustainable long-term establishment and management practices that maximise the ability of the selected grass to survive and grow under a particular set of salinity and usage parameters. Salt-tolerant turf grasses with potential for special use situations were trialled under field conditions at three sites within the Gold Coast City Council, while three sites, established under TU02005 within the Redland City Council boundaries were monitored for continued grass survival. Several randomised block experiments within Gold Coast City were established to compare the health and longevity of seashore paspalum (Paspalum vaginatum), Manila grass (Zoysia matrella), as well as the more tolerant cultivars of other species like buffalo grass (Stenotaphrum secundatum) and green couch (Cynodon dactylon). Whilst scientific results were difficult to achieve in the field situation, where conditions cannot be controlled, these trials provided valuable observational evidence of the likely survival of these species. Alternatives to laying full sod such as sprigging were investigated, and were found to be more appropriate for areas of low traffic as the establishment time is greater. Trials under controlled and protected conditions successfully achieved a full cover of Paspalum vaginatum from sprigs in a 10 week time frame. Salt affected sites are often associated with poor soil structure. Part of the research investigated techniques for the alleviation of soil compaction frequently found on saline sites. Various methods of soil de-compaction were investigated on highly compacted heavy clay soil in Redlands City. It was found that the heavy duplex soil of marine clay sediments required the most aggressive of treatments in order to achieve limited short-term effects. Interestingly, a well constructed sports field showed a far greater and longer term response to de-compaction operations, highlighting the importance of appropriate construction in the successful establishment and management of turfgrasses on salt affected sites. Fertiliser trials in this project determined plant demand for nitrogen (N) to species level. This work produced data that can be used as a guide when fertilising, in order to produce optimal growth and quality in the major turf grass species used in public parkland. An experiment commenced during TU02005 and monitored further in this project, investigated six representative warm-season turfgrasses to determine the optimum maintenance requirements for fertiliser N in south-east Queensland. In doing so, we recognised that optimum level is also related to use and intensity of use, with high profile well-used parks requiring higher maintenance N than low profile parks where maintaining botanical composition at a lower level of turf quality might be acceptable. Kikuyu (Pennisetum clandestinum) seemed to require the greatest N input (300-400 kg N/ha/year), followed by the green couch (Cynodon dactylon) cultivars ‘Wintergreen’ and ‘FLoraTeX’ requiring approximately 300 kg N/ha/year for optimal condition and growth. ‘Sir Walter’ (Stenotaphrum secundatum) and ‘Sea Isle 1’ (Paspalum vaginatum) had a moderate requirement of approximately 200 kg/ha/year. ‘Aussiblue’ (Digitaria didactyla)maintained optimal growth and quality at 100-200 kg N/ha/year. A set of guidelines has been prepared to provide various options from the construction and establishment of new grounds, through to the remediation of existing parklands by supporting the growth of endemic grasses. They describe a best management process through which salt affected sites should be assessed, remediated and managed. These guidelines, or Best Management Practices, will be readily available to councils. Previously, some high salinity sites have been turfed several times over a number of years (and Council budgets) for a 100% failure record. By eliminating this budgetary waste through targeted workable solutions, local authorities will be more amenable to investing appropriate amounts into these areas. In some cases, this will lead to cost savings as well as resulting in better quality turf. In all cases, however, improved turf quality will be of benefit to ratepayers, directly through increased local use of open space in parks and sportsfields and indirectly by attracting tourists and other visitors to the region bringing associated economic benefits. At the same time, environmental degradation and erosion of soil in bare areas will be greatly reduced.
Resumo:
India is the midst of oil crisis.Many long term solution have been suggested.The question that is being asked is: can something be done immediately? Prof. A.K.N Reddy, who leads the group on the application of science & Techonology to rural area at the Indian Institute of Science has come with simple solutions which appears to well within our present technological capability.
Resumo:
Take home messages: Plant only high quality seed that has been germ and vigour tested and treated with a registered seed dressing Avoid poorly drained paddocks and those with a history of lucerne, medics or chickpea Phytophthora root rot, PRR; do not grow Boundary if you even suspect a PRR risk Select best variety suited to soil type, farming system and disease risk Beware Ascochyta: follow recommendations for your variety and district Minimise risk of virus by retaining stubble, planting on time and at optimal rate, controlling weeds and ensuring adequate plant nutrition Test soil to determine risk of salinity and sodicity – do not plant chickpeas if ECe > 1.0-1.3 dS/m. Beware early desiccation of seed crops – know how to tell when 90-95% seeds are mature
Resumo:
Increasing salinity levels in freshwater and coastal environments caused by sea level rise linked to climate change is now recognized to be a major factor that can impact fish growth negatively, especially for freshwater teleost species. Striped catfish (Pangasianodon hypophthalmus) is an important freshwater teleost that is now widely farmed across the Mekong River Delta in Vietnam. Understanding the basis for tolerance and adaptation to raised environmental salinity conditions can assist the regional culture industry to mitigate predicted impacts of climate change across this region. Attempt of next generation sequencing using the ion proton platform results in more than 174 million raw reads from three tissue libraries (gill, kidney and intestine). Reads were filtered and de novo assembled using a variety of assemblers and then clustered together to generate a combined reference transcriptome. Downstream analysis resulted in a final reference transcriptome that contained 60,585 transcripts with an N50 of 683 bp. This resource was further annotated using a variety of bioinformatics databases, followed by differential gene expression analysis that resulted in 3062 transcripts that were differentially expressed in catfish samples raised under two experimental conditions (0 and 15 ppt). A number of transcripts with a potential role in salinity tolerance were then classified into six different functional gene categories based on their gene ontology assignments. These included; energy metabolism, ion transportation, detoxification, signal transduction, structural organization and detoxification. Finally, we combined the data on functional salinity tolerance genes into a hypothetical schematic model that attempted to describe potential relationships and interactions among target genes to explain the molecular pathways that control adaptive salinity responses in P. hypophthalmus. Our results indicate that P. hypophthalmus exhibit predictable plastic regulatory responses to elevated salinity by means of characteristic gene expression patterns, providing numerous candidate genes for future investigations.
Resumo:
After the Second World War the public was shocked to learn about the horrors perpetrated. As a response to the Holocaust, the newly established United Nations adopted the Genocide Convention of 1948 to prevent future genocides and to punish the perpetrators. The Convention remained, however, almost dead letter until the present day. In 1994, the long-lasted tension between the major groups of Hutu and Tutsi in Rwanda erupted in mass scale violence towards the Tutsi ethnic group. The purpose was to eradicate the Tutsi population of Rwanda. The international community did not halt the genocide. It stood by idle, failing to follow the swearing-in of the past. The United Nations established the International Criminal Tribunal for Rwanda (the ICTR) to bring to justice persons responsible for the genocide. Ever since its creation the ICTR has delivered a wealth of judgements elucidating the legal ingredients of the crime of genocide. The case law on determining the membership of national, ethnic, racial or religious groups has gradually shifted from the objective to subjective position. The membership of a group is seen as a subjective rather than objective concept. However, a totally subjective approach is not accepted. Therefore, it is necessary to determine some objective existence of a group. The provision on the underlying offences is not so difficult to interpret compared to the corresponding one on the protected groups and the mental element of genocide. The case law examined, e.g., whether there is any difference between the words killing and meurtre, the nature of mental harm caused by the perpetrator and sexual violence in the conflict. The mental element of genocide or dolus specialis of genocide is not thoroughly examined in the case law of the ICTR. In this regard, reference in made, in addition, to the case law of the other ad hoc Tribunal. The ICTR has made a significant contribution to the law of genocide and international criminal justice in general. The corpus of procedural and substantive law constitutes a basis for subsequent trials in international and hybrid tribunals. For national jurisdictions the jurisprudence on substantive law is useful while prosecuting international crimes.
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The life cycle and genetic diversity of the red alga Furcellaria lumbricalis (Hudson) Lamouroux were investigated in 15 populations in northern Europe. The occurrence of different life cycle phases and seasonality of reproduction were studied in four brackish populations in the northern Baltic Sea. Furthermore, a new method, based on genome screening with ISSR markers combined with a restriction-ligation method, was developed to discover microsatellite markers for population genetic analyses. The mitochondrial DNA cox2-3 spacer sequence and four microsatellite markers were used to examine the genetic diversity and differentiation of red algal populations in northern Europe. In addition, clonality and small-scale genetic structure of one Irish and four Baltic Sea populations were studied with microsatellite markers. It was discovered that at the low salinities of the northern Baltic Sea, only tetrasporophytes and males were present in the populations of F. lumbricalis and that winter was the main season for tetrasporangial production. Furthermore, the population occurring at the lowest salinity (3.6 practical salinity units, psu) did not produce spores. The size of the tetraspores was smaller in the Baltic Sea populations than that in the Irish population, and there were more deformed spores in the Baltic Sea populations than in the Irish populations. Studies with microsatellite markers indicated that clonality is a common phenomenon in the Baltic Sea populations of F. lumbricalis, although the proportion of clonal individuals varied among populations. Some genetic divergence occurred within locations both in Ireland and in the northern Baltic Sea. Even though no carpogonia were detected in the field samples during the study, the microsatellite data indicated that sexual reproduction occurs at least occasionally in the northern Baltic Sea. The genetic diversity of F. lumbricalis was highest in Brittany, France. Since no variation was discovered in the mtDNA cox2-3 spacer sequence, which is generally regarded as an informative phylogeographic marker in red algae, it can be assumed that the studied populations probably share the same origin.
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Environmental factors contribute to over 70% of crop yield losses worldwide. Of these drought and salinity are the most significant causes of crop yield reduction. Rice is an important staple crop that feeds more than half of the world’s population. However among the agronomically important cereals rice is the most sensitive to salinity. In the present study we show that exogenous expression of anti-apoptotic genes from diverse origins, AtBAG4 (Arabidopsis), Hsp70 (Citrus tristeza virus) and p35 (Baculovirus), significantly improves salinity tolerance in rice at the whole plant level. Physiological, biochemical and agronomical analyses of transgenic rice expressing each of the anti-apoptotic genes subjected to salinity treatment demonstrated traits associated with tolerant varieties including, improved photosynthesis, membrane integrity, ion and ROS maintenance systems, growth rate, and yield components. Moreover, FTIR analysis showed that the chemical composition of salinity-treated transgenic plants is reminiscent of non-treated, unstressed controls. In contrast, wild type and vector control plants displayed hallmark features of stress, including pectin degradation upon subjection to salinity treatment. Interestingly, despite their diverse origins, transgenic plants expressing the anti-apoptotic genes assessed in this study displayed similar physiological and biochemical characteristics during salinity treatment thus providing further evidence that cell death pathways are conserved across broad evolutionary kingdoms. Our results reveal that anti-apoptotic genes facilitate maintenance of metabolic activity at the whole plant level to create favorable conditions for cellular survival. It is these conditions that are crucial and conducive to the plants ability to tolerate/adapt to extreme environments.
Resumo:
Communication and Political Crisis explores the role of the global media in a period of intensifying geopolitical conflict. Through case studies drawn from domestic and international political crises such as the conflicts in the Middle East and Ukraine, leading media scholar Brian McNair argues that the digitized, globalized public sphere now confronted by all political actors has produced new opportunities for social progress and democratic reform, as well as new channels for state propaganda and terrorist spectaculars such as those performed by the Islamic State and Al Qaeda. In this major work, McNair argues that the role of digital communication will be crucial in determining the outcome of pressing global issues such as the future of feminism and gay rights, freedom of speech and media, and democracy itself.