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Historical Records (historical + record)
Selected AbstractsCOLLISIONS BETWEEN SHIPS AND WHALESMARINE MAMMAL SCIENCE, Issue 1 2001David W. Laist Abstract Although collisions with motorized ships are a recognized source of whale mortality, little has been done to compile information on the frequency of their occurrence or contributing factors. We searched historical records and computerized stranding databases for evidence of ship strikes involving great whales (i. e., baleen whales and the sperm whale). Historical records suggest that ship strikes fatal to whales first occurred late in the 1800s as ships began to reach speeds of 13-15 kn, remained infrequent until about 1950, and then increased during the 1950s-1970s as the number and speed of ships increased. Of 11 species known to be hit by ships, fin whales (Balaenoptera physalus) are struck most frequently; right whales (Eubalaena glacialis and E. australis), humpback whales (Megaptera novaeangliae), sperm whales (Physeter catodon), and gray whales (Escbricbtius robustus) are hit commonly. In some areas, one-third of all fin whale and right whale strandings appear to involve ship strikes. To assess contributing factors, we compiled descriptions of 58 collisions. They indicate that all sizes and types of vessels can hit whales; most lethal or severe injuries are caused by ships 80 m or longer; whales usually are not seen beforehand or are seen too late to be avoided; and most lethal or severe injuries involve ships travelling 14 kn or faster. Ship strikes can significantly affect small populations of whales, such as northern right whales in the western North Atlantic. In areas where special caution is needed to avoid such events, measures to reduce the vessel speed below 14 kn may be beneficial. [source] A historical record of mercury contamination in southern florida (USA) as inferred from avian feather tissue: Contribution R-09888 of the Journal Series, Florida Agricultural Experiment StationENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 6 2004Peter C. Frederick Abstract During the late 1980s, the upper trophic-level biota of the Everglades (FL, USA) was recognized as being highly contaminated with mercury (Hg). However, the timing and pattern of that increase is poorly known, and no information is available about mercury contam ination in Everglades wildlife prior to 1974. We measured methylmercury concentrations in feathers of white ibises (n = 33), great egrets (n = 7), anhingas (n = 21), and great blue herons (n = 12) from museum specimens collected from 1910 through 1980 and combined them with more recent feather samples collected from live birds (1985,2000, n = 98, 37, 49, and 7, respectively). We found no evidence of contamination of museum samples with inorganic mercuric preservatives (0.01,0.28% of total Hg in feathers). All species showed relatively low concentrations of mercury through the 1970s (<5 ,l/L dry wt for anhingas, ibises, and egrets, <10 ,l/L for herons). Samples from all species taken during the 1990s showed a large and significant increase (4,5X) in MeHg concentration. This evidence suggests that most of the increase in Hg deposition during the 20th century in south Florida occurred during the last two to three decades, which is consistent with information about local source deposition. Contamination levels prior to the 1970s appear to have been associated with normal reproduction in these birds, suggesting partial evidence for a threshold of reproductive impairment. [source] The Early History (1909,1961) of Epilepsia, the Journal of the International League Against Epilepsy, and Its Echoes TodayEPILEPSIA, Issue 1 2007Simon Shorvon Summary:, This paper records the history of Epilepsia, the journal of the International League Against Epilepsy, from its inception in 1908/1909 until the beginning of its fourth series in 1961. During this time, publication was interrupted on three occasions and so the journal appeared in four series, with a complex numbering system. Over the years, the content and format of the journal has varied. Its role has changed over the years, at times primarily as a scientific organ and at other times as a source of ILAE news and reports. Concerns throughout its history have included its role as an historical record, its international representation, financial vicissitude, quality of papers, the balance between basic and clinical science, the value of clinical papers, and issues of overspecialization. Epilepsia is today the leading clinical epilepsy journal; but these are still significant concerns, and a knowledge of the history of Epilepsia is important for understanding the current position of the journal. [source] When half of the population died: the epidemic of hemorrhagic fevers of 1576 in MexicoFEMS MICROBIOLOGY LETTERS, Issue 1 2004Rodofo Acuna-Soto Abstract During the 16th century, Mexico suffered a demographic catastrophe with few parallels in world's history. In 1519, the year of the arrival of the Spaniards, the population in Mexico was estimated to be between 15 and 30 million inhabitants. Eighty-one years later, in 1600, only two million remained. Epidemics (smallpox, measles, mumps), together with war, and famine have been considered to be the main causes of this enormous population loss. However, re-evaluation of historical data suggests that approximately 60,70% of the death toll was caused by a series of epidemics of hemorrhagic fevers of unknown origin. In order to estimate the impact of the 1576 epidemic of hemorrhagic fevers on the population we analyzed the historical record and data from the 1570 and 1580 censuses of 157 districts. The results identified several remarkable aspects of this epidemic: First, overall, the population loss for these 157 districts was 51.36%. Second, there was a clear ethnic preference of the disease, the Spanish population was minimally affected whereas native population had high mortality rate. Third, the outbreak originated in the valleys of central Mexico whence it evolved as an expansive wave. Fourth, a positive correlation between altitude and mortality in central Mexico was found. Fifth, a specific climatic sequence of events was associated with the initiation and dissemination of the hemorrhagic fevers. Although the last epidemic of hemorrhagic fevers in Mexico ended in 1815, many questions remain to be answered. Perhaps the most relevant ones are whether there is a possible reemergence of the hemorrhagic fevers and how vulnerable we are to the disease. [source] Performing ,Ostalgie': Leander Haussmann's SonnenalleeGERMAN LIFE AND LETTERS, Issue 2 2003Paul Cooke The following article examines Leander Haußmann's hit youth comedy Sonnenallee (1999). In particular it attempts to challenge many reviewers who saw the film as nothing more than a self-indulgent piece of ,Ostalgie' which trivialises the oppressive reality of life in the GDR. Instead, it argues that the film deliberately highlights the competing tensions at work within contemporary nostalgia for the East German state. On the one hand, Sonnenallee constructs ,Ostalgie' as a response to fears among many East Germans that the true nature of their everyday experience is being elided from the historical record. Through the use of an intricate network of Eastern and Western cultural references, the film attempts to counter this impulse by highlighting the importance of both these cultural traditions to youth in the GDR. In so doing the film translates the experience of East Germans into a cultural language that West Germans will understand, thereby ,normalising' this experience. On the other hand, and seeming to contradict this project, the film also challenges simplistically rose-tinted views of the East. Consequently, the film forces the East German spectator to reflect upon, and ultimately reject, any manifestations of Ostalgie which would ostensibly call for a return to the GDR. [source] Parameter estimation in semi-distributed hydrological catchment modelling using a multi-criteria objective functionHYDROLOGICAL PROCESSES, Issue 22 2007Hamed Rouhani Abstract Output generated by hydrologic simulation models is traditionally calibrated and validated using split-samples of observed time series of total water flow, measured at the drainage outlet of the river basin. Although this approach might yield an optimal set of model parameters, capable of reproducing the total flow, it has been observed that the flow components making up the total flow are often poorly reproduced. Previous research suggests that notwithstanding the underlying physical processes are often poorly mimicked through calibration of a set of parameters hydrologic models most of the time acceptably estimates the total flow. The objective of this study was to calibrate and validate a computer-based hydrologic model with respect to the total and slow flow. The quick flow component used in this study was taken as the difference between the total and slow flow. Model calibrations were pursued on the basis of comparing the simulated output with the observed total and slow flow using qualitative (graphical) assessments and quantitative (statistical) indicators. The study was conducted using the Soil and Water Assessment Tool (SWAT) model and a 10-year historical record (1986,1995) of the daily flow components of the Grote Nete River basin (Belgium). The data of the period 1986,1989 were used for model calibration and data of the period 1990,1995 for model validation. The predicted daily average total flow matched the observed values with a Nash,Sutcliff coefficient of 0·67 during calibration and 0·66 during validation. The Nash,Sutcliff coefficient for slow flow was 0·72 during calibration and 0·61 during validation. Analysis of high and low flows indicated that the model is unbiased. A sensitivity analysis revealed that for the modelling of the daily total flow, accurate estimation of all 10 calibration parameters in the SWAT model is justified, while for the slow flow processes only 4 out of the set of 10 parameters were identified as most sensitive. Copyright © 2007 John Wiley & Sons, Ltd. [source] Simulating the response of a closed-basin lake to recent climate changes in tropical West Africa (Lake Bosumtwi, Ghana)HYDROLOGICAL PROCESSES, Issue 13 2007Timothy M. Shanahan Abstract Historical changes in the level of Lake Bosumtwi, Ghana, have been simulated using a catchment-scale hydrological model in order to assess the importance of changes in climate and land use on lake water balance on a monthly basis for the period 1939,2004. Several commonly used models for computing evaporation in data-sparse regions are compared, including the Penman, the energy budget, and the Priestley,Taylor methods. Based on a comparison with recorded lake level variations, the model with the energy-budget evaporation model subcomponent is most effective at reproducing observed lake level variations using regional climate records. A sensitivity analysis using this model indicates that Lake Bosumtwi is highly sensitive to changes in precipitation, cloudiness and temperature. However, the model is also sensitive to changes in runoff related to vegetation, and this factor needs to be considered in simulating lake level variations. Both interannual and longer-term changes in lake level over the last 65 years appear to have been caused primarily by changes in precipitation, though the model also suggests that the drop in lake level over the last few decades has been moderated by changes in cloudiness and temperature over that time. Based on its effectiveness at simulating the magnitude and rate of lake level response to changing climate over the historical record, this model offers a potential future opportunity to examine the palaeoclimatic factors causing past lake level fluctuations preserved in the geological record at Lake Bosumtwi. Copyright © 2006 John Wiley & Sons, Ltd. [source] GLOBAL EVIDENCE ON THE EQUITY RISK PREMIUMJOURNAL OF APPLIED CORPORATE FINANCE, Issue 4 2003Elroy Dimson The size of the equity risk premium,the incremental return that shareholders require to hold risky equities rather than risk-free securities,is a key issue in corporate finance. Financial economists generally measure the equity premium over long periods of time in order to obtain reliable estimates. These estimates are widely used by investors, finance professionals, corporate executives, regulators, lawyers, and consultants. But because the 20th century proved to be a period of such remarkable growth in the U.S. economy, estimates of the risk premium that rely on past market performance may be too high to serve as a reliable guide to the future. The authors analyze a 103-year history of risk premiums in 16 countries and conclude that the U.S. risk premium relative to Treasury bills was 5.3% for that period,lower than previous studies suggest,as compared to 4.2% for the U.K. and 4.5% for a world index. But the article goes on to observe that the historical record may still overstate expectations of the future risk premium, partly because market volatility in the future may be lower than in the past, and partly because of a general decline in risk resulting from new technological advances and increased diversification opportunities for investors. After adjusting for the expected impact of these factors, the authors calculate forward-looking equity risk premiums of 4.3% for the U.S., 3.9% for the U.K., and 3.5% for the world index. At the same time, however, they caution that the risk premium can fluctuate over time and that managers should make appropriate adjustments when there are compelling economic reasons to think that expected premiums are unusually high or low. [source] Historical and contemporary distributions of carnivores in forests of the Sierra Nevada, California, USAJOURNAL OF BIOGEOGRAPHY, Issue 8 2005William J. Zielinski Abstract Aim, Mammalian carnivores are considered particularly sensitive indicators of environmental change. Information on the distribution of carnivores from the early 1900s provides a unique opportunity to evaluate changes in their distributions over a 75-year period during which the influence of human uses of forest resources in California greatly increased. We present information on the distributions of forest carnivores in the context of two of the most significant changes in the Sierra Nevada during this period: the expansion of human settlement and the reduction in mature forests by timber harvest. Methods, We compare the historical and contemporary distributions of 10 taxa of mesocarnivores in the conifer forests of the Sierra Nevada and southern Cascade Range by contrasting the distribution of museum and fur harvest records from the early 1900s with the distribution of detections from baited track-plate and camera surveys conducted from 1996 to 2002. A total of 344 sample units (6 track plates and 1 camera each) were distributed systematically across c. 3,000,000 ha area over a 7-year period. Results, Two species, the wolverine (Gulo gulo) and the red fox (Vulpes vulpes), present in the historical record for our survey area, were not detected during the contemporary surveys. The distributions of 3 species (fisher [Martespennanti], American marten [M. americana], and Virginia opossum [Didelphisvirginiana]) have substantially changed since the early 1900s. The distributions of fishers and martens, mature-forest specialists, appeared to have decreased in the northern Sierra Nevada and southern Cascade region. A reputed gap in the current distribution of fishers was confirmed. We report for the first time evidence that the distribution of martens has become fragmented in the southern Cascades and northern Sierra Nevada. The opossum, an introduced marsupial, expanded its distribution in the Sierra Nevada significantly since it was introduced to the south-central coast region of California in the 1930s. There did not appear to be any changes in the distributions of the species that were considered habitat generalists: gray fox (Urocyon cinereoargenteus), striped skunk (Mephitis mephitis), western spotted skunk (Spilogale gracilis), or black bear (Ursus americanus). Detections of raccoons (Procyon lotor) and badgers (Taxidea taxus) were too rare to evaluate. Contemporary surveys indicated that weasels (M. frenata and M. erminea) were distributed throughout the study area, but historical data were not available for comparison. Main conclusions, Two species, the wolverine and Sierra Nevada red fox, were not detected in contemporary surveys and may be extirpated or in extremely low densities in the regions sampled. The distributions of the mature forest specialists (marten and fisher) appear to have changed more than the distributions of the forest generalists. This is most likely due to a combination of loss of mature forest habitat, residential development and the latent effects of commercial trapping. Biological characteristics of individual species, in combination with the effect of human activities, appear to have combined to affect the current distributions of carnivores in the Sierra Nevada. Periodic resampling of the distributions of carnivores in California, via remote detection methods, is an efficient means for monitoring the status of their populations. [source] Floral free fall in the Swiss lowlands: environmental determinants of local plant extinction in a peri-urban landscapeJOURNAL OF ECOLOGY, Issue 4 2007IVANA STEHLIK Summary 1Local floras are being depleted by a host of human activities, including habitat destruction and fragmentation, eutrophication, and the intensification of agriculture. Species with particular ecological demands or life-history attributes are more prone to extinction than species with a broader niche. 2We used an old herbarium from the municipality of Küsnacht (Swiss lowlands) as a historical record for comparison with contemporary plant diversity. This comparison revealed that 17% to 28% of all vascular plants that occurred between 1839 and 1915 were extinct by 2003. 3Species of different habitats and life-forms had significantly different rates of extinction: wetlands, disturbed sites and meadows lost most species, whereas forests and rocky habitats were least affected; aquatics and annuals were most prone to extinction, geophytes and hemicryptophytes were intermediate, and phanerophytes and chamaephytes were least affected. 4Species adapted to nutrient-poor soils suffered highest extinction in all habitats, indicating that eutrophication poses an urgent threat to species diversity. Light and soil moisture requirements also had significant effects on extinction, but the direction of the effect varied by habitat. 5When species were grouped into IUCN categories of the red list of Switzerland, the rank order of the observed extinction matched the red list assignment. 6Because many of the remaining species had high estimated extinction probabilities and because extinction is often delayed (extinction debt), a substantial part of the remaining flora of Küsnacht is likely to go extinct in the near future. This will increase the dominance of the common species that already comprise 81% of the local flora. 7The rates and patterns of extinction in Küsnacht are probably representative of surrounding Swiss lowlands and peri-urban landscapes in most developed countries. Studies such as ours can serve as a call for action and form a basis for future monitoring of biodiversity. [source] An Exegesis on Currency and Banking CrisesJOURNAL OF ECONOMIC SURVEYS, Issue 3 2004Janice Boucher Breuer Currency and banking crises are characterized according to some standards in the literature and their historical record summarized. The development of the literature from first through fourth-generation, or so-called ,institutional' models is reviewed. A digression on institutions is provided along with some sidebars on the development of the literature on institutions as it relates to economic growth. The empirical research on third-generation (or twin crises) models and on institutional models of currency and banking crises, which are so far scarce, is covered too. A summary of the main policy issues for dealing with financial crises is presented. The paper closes with an emphasis on institutions and a call for more research directed at institutions and their role in the financial system. [source] TREE RING RECONSTRUCTIONS OF STREAMFLOW FOR THREE CANADIAN PRAIRIE RIVERS,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 3 2003Roslyn A. Case ABSTRACT: Information regarding long term hydrological variability is critical for the effective management of surface water resources. In the Canadian Prairie region, growing dependence on major river systems for irrigation and other consumptive uses has resulted in an increasing vulnerability to hydrological drought and growing interprovincial tension. This study presents the first dendrochronological records of streamflow for Canadian Prairie rivers. We present 1,113-year, 522-year, and 325-year reconstructions of total water year (October to September) streamflow for the North Saskatchewan, South Saskatchewan, and Saskatchewan Rivers, respectively. The reconstructions indicate relatively high flows during the 20th Century and provide evidence of past prolonged droughts. Low flows during the 1840s correspond with aridity that extended over much of the western United States. Similarly, an exceptional period of prolonged low flow conditions, approximately 900 A.D. to 1300 A.D., is coincident with evidence of sustained drought across central and western North America. The 16th Century megadrought of the western United States and Mexico, however, does not appear to have had a major impact on the Canadian rivers. The dendrohydrological records illustrate the risks involved if future water policy and infrastructure development in the Canadian Prairies are based solely on records of streamflow variability over the historical record. [source] Vegetation change from chronic stress events: Detection of the effects of tide gate removal and long-term drought on a tidal marshJOURNAL OF VEGETATION SCIENCE, Issue 3 2007Paul R. Wetzel Godfrey & Wooten (1979, 1981) Abstract Question: Chronic stress events are defined as disturbance events that exceed the lifespan of the dominant plant species, fluctuate in intensity and lack abruptness or physical destruction of biomass. Can the effects of chronic stress events be measured on vegetation communities? Did two chronic stress events, the removal of a tide gate and a four year drought, cause a temporary or permanent shift in the vegetation communities of a tidal marsh? Location: Tidal marsh in southeastern United States. Methods: Change in species composition and dominance and community change on a landscape level salinity gradient were measured between time periods ranging from four months to seven years to construct a statistical baseline reference community at freshwater, oligohaline, and mesohaline sections of a tidal marsh. Statistical shifts in the plant community were defined as changes in the plant community that fell outside of the defined baseline reference community. Results: Plant community changes outside of the reference community occurred in 13 out of 378 community comparisons. Removal of the tide gate had a greater effect on interstitial salinity levels than the drought and was most intense in the oligohaline marsh, where between 20 to 45% of the freshwa-ter/oligohaline community types permanently converted to oligohaline community types. However, community shifts in the freshwater and oligohaline marsh induced by the drought were temporary, lasting from 1 to 3+ years. Neither chronic stress event permanently altered the mesohaline plant communities. Conclusion: The effects of chronic stress events could be detected; an extended historical record of vegetation change (18 years) was necessary to identify community shifts outside of a reference condition of the community and to determine if those shifts were permanent or temporary. [source] How about alternatives to phthalate plasticizers?JOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 4 2003Leonard G. Krauskopf Phthalate plasticizers have historically served as the preferred plasticizers to impart flexibility to PVC and several other polar polymers. They provide a desirable balance of cost and performance properties. Their acceptable and safe use is unmatched in medical appliances, food processing, and packaging applications, as well as in many other end uses. Potential alternatives do not have the historical record of acceptable performance found with phthalate plasticizers. Nevertheless, the "Precautionary Principle" has caused certain segments of society to clamor for alternates to phthalate plasticizers. This paper reviews known "non-phthalate" plasticizers and provides comparisons to the traditional "General Purpose" (GP) phthalate plasticizers; "General Purpose" plasticizers are those that impart optimum overall performance properties in PVC at lowest cost. [source] A historical analysis of the relationship between encephalitis lethargica and postencephalitic parkinsonism: A complex rather than a direct relationship,MOVEMENT DISORDERS, Issue 9 2010Joel A. Vilensky PhD Abstract Postencephalitic parkinsonism has been considered unique among disorders with parkinsonian features because it is believed to have a unitary etiology associated with the virus that presumably caused encephalitis lethargica. Careful analysis of the historical record, however, suggests that this relationship is more complex than commonly perceived. In most cases, the diagnosis of acute encephalitis lethargica was made post hoc, and virtually any catarrh-like illness was considered to have represented encephalitis lethargica, often after an oral history-taking that was undoubtedly subject to patient recall and physician bias. Also, postencephalitic parkinsonism and oculogyric crises were not recognized as sequelae to encephalitis lethargica until well after other sequelae such as movement disorders and mental disturbances had been identified (see previous paper). We suggest here that the relationship between encephalitis lethargica and postencephalitic parkinsonism is not simplistic, i.e., encephalitis lethargica was not solely responsible for the etiology of postencephalitic parkinsonism, thus aligning the latter with most other parkinsonian disorders that are now believed to have multiple causes. © 2010 Movement Disorder Society [source] Drafting the BOLERO PlanPUBLIC ADMINISTRATION REVIEW, Issue 6 2009Gene A. Brewer Editor This year marks the sixty-fifth anniversary of the D-Day invasion, when Allied forces crossed the English Channel and established beachheads along a 50-mile stretch of the Normandy coast in northern France. Troops overcame stiff resistance and systematically moved inland, liberating Northern Europe and forcing the surrender of Germany and the end of World War II in that part of the world. The D-Day invasion took place on June 6, 1944, but its planning began more than two years earlier. This case studies the strategic planning that led up to the invasion. The Operations Division of the War Department General Staff, formerly known as the War Plans Division, was the principal staff agency of the U.S. Army high command during World War II. The story focuses on the Operations Division's role in formulating a strategic plan for ending the war as well as Operation BOLERO,the American military troop buildup in Great Britain that preceded the cross-channel invasion. By reprinting this case from the original U.S. Army historical record, PAR pays tribute to the brave men and women who planned and executed this bold maneuver, many of whom paid the ultimate price to achieve victory and restore freedom. Popularized as the "Greatest Generation," they were ordinary people who answered the call of public service with extraordinary bravery and sacrifice. Members of the modern-day public administration community proudly stand on their shoulders. This chapter-length excerpt is taken from Ray S. Cline, Washington Command Post: The Operations Division (Washington, DC: Office of the Chief of Military History, Department of the Army, 1951), chapter IX, "Case History: Drafting the BOLERO Plan," pp. 143,63. [source] Hurricanes and socio-economic development on Niue IslandASIA PACIFIC VIEWPOINT, Issue 2 2000Judith C. Barker This case study investigates the complex ways that recurrent ecological damage affected the course of socio-economic development on Niue Island, a Pacific micro-state. In tracing the historical record of droughts and hurricanes from 1900 to 1990, it is clear that severely inclement weather repeatedly destroyed agricultural development endeavours on the island leading to stagnation in this economic sector. In the aftermath of such disasters there were additional widespread social, political, and economic responses resulting in insidious but inexorable change. These responses , metaphoric ,winds of change', constituted, bolstered and sustained the transition to a MIRAB economy. [source] Commentary: Business,Black Swans,and the,Use and Abuse,of a NotionAUSTRALIAN ACCOUNTING REVIEW, Issue 2 2010Graeme Dean Historical enquiry reveals how ideas mutate. This paper traces how ideas and practices underpinning initial understandings of fair value accounting (FVA) have changed as the concept drifted from the utility rate-setting context to that of corporate financial reporting. The recall of history for the purpose of ,learning lessons from the past' has frequently resulted in misunderstandings of the historical record and misapplication of so-called lessons. A more fruitful approach to recalling history is to gain insights into the development of the ideas (good and bad) that have contributed to current predicaments. Initially fair value was the basis for specific pricing calculations related to companies with a highly restricted scope of operations. Later, more by accident than design, the concept became a general purpose application used in the financial statements of highly and freely adaptive companies. The mark-to-market (MtM) dispute emerging in the global financial crisis (GFC) has given rise to a further mutation of the use of FVA. Discarding MtM contradicts what history tells us was the purpose of adopting fair value into accounting for adaptive companies. This analysis also highlights how conducive accounting theory and practice are subject to politicisation. Accounting is an apparently unresisting victim of interested parties' special pleading, resulting in the corruption of its technical function , in this case primarily because it is inconvenient to have accounting data,tell it how it is. [source] Adaptation and Appropriation on the Colonial Frontier: Indigenous Leadership in the Colombian Chocó, 1670,1808BULLETIN OF LATIN AMERICAN RESEARCH, Issue 2 2007CAROLINE A. WILLIAMS This article explores the consequences for the native population of the Colombian Chocó of the emergence, over the course of the eighteenth century, of an elite of caciques and indios mandones or principales whose functions of powers far exceeded those of the warrior chiefs that had traditionally acted as leaders of their people. Appointed for the purpose of facilitating the collection of tribute and the supply of labour to European settlers, caciques and mandones were almost universally rejected by native communities during the early phases of Spanish colonisation (c. 1630,1690), and they disappear from the historical record after Independence. Eighteenth-century sources, however, not only record the existence of a clearly defined elite of mandones or principales in villages across the region, but show these individuals engaging actively with the colonial authorities, on behalf of their communities, at local and audiencia levels. This article argues that, at a time of a much strengthened European presence in the region, caciques and mandones came to understand their roles in ways that were entirely different from those intended by the Spanish, and in so doing acquired the legitimacy that had eluded their seventeenth-century predecessors. Far from serving merely as intermediaries between settlers and indigenous populations, indios mandones acted as negotiators on behalf of the indigenous population, whose task was to defend and/or advance the interests of the communities they had been appointed to control. [source] Controls on modern alluvial fan processes in the central Alps, northern ItalyEARTH SURFACE PROCESSES AND LANDFORMS, Issue 3 2004Giovanni B. Crosta Abstract Alluvial fan development in Alpine areas is often affected by catastrophic sedimentary processes associated with extreme ,oods events, causing serious risks for people living on the fans. Hazard assessment in these areas depends on proper identi,cation of the dominant sedimentary processes on the fans. Data from a set of 209 alluvial fans from the central Alps of Italy are presented in this paper and analysed with the help of various statistical techniques (linear regression, principal components analysis, cluster analysis, discriminant analysis and logistic regression). First, we used modern sedimentary facies and historical records (,ood events since 15th century), to distinguish between the two dominant sedimentary processes on alluvial fans: debris ,ows and stream,ows. Then, in order to analyse the main controls on past and present fan processes, 36 morphological, geological and land-use variables were analysed. As with observations for arid-environment fans, catchment morphology is the most in,uential factor in the study area, whereas geology and land use are minor controls. The role of climatic change and landsliding within the catchments also seems to be very important and is discussed. Statistical techniques also help in differentiating groups of alluvial fans by sets of controlling factors, including stage and type of evolution. Finally, by using discriminant analysis and logistic regression, we classi,ed alluvial fans according to the dominant sedimentary process, with a success rate ranging between 75 and 92 per cent. Copyright © 2004 John Wiley & Sons, Ltd. [source] Shifting altitudinal distribution of outbreak zones of winter moth Operophtera brumata in sub-arctic birch forest: a response to recent climate warming?ECOGRAPHY, Issue 2 2007Snorre B. Hagen Climatic change is expected to affect the extent and severity of geometrid moth outbreaks, a major disturbance factor in sub-arctic birch forests. Previous studies have reported that the two geometrid species involved, autumnal moth and winter moth, differ in their temperature requirements and, consequently, in their altitudinal and latitudinal distribution patterns. In this study, we document the altitudinal distribution of winter moth outbreaks in a large coastal area in northern Norway. We show that, in the present winter moth outbreak, defoliated birch stands were seen as distinct zones with a rather constant width in the uppermost part of the forest and where the upper limit coincided with the forest line. The outbreak zone closely followed the spatially variable forest line as an undulating belt, although some of the variation in outbreak zone width was also related to variation in topographical variables, such as distance from the coast, forest line altitude, and slope of the terrain. A distinct outbreak zone at the altitudinal forest line is the typical picture that has been depicted in more qualitative historical records on previous outbreaks of autumnal moth rather than winter moth. We suggest that the recent documented climate warming in this region may have induced a shift in distribution of the winter moth both relative to topography and geography. Further investigation is, however, required to substantiate these suspicions. [source] The myth of plant species saturationECOLOGY LETTERS, Issue 4 2008Thomas J. Stohlgren Abstract Plant species assemblages, communities or regional floras might be termed ,saturated' when additional immigrant species are unsuccessful at establishing due to competitive exclusion or other inter-specific interactions, or when the immigration of species is off-set by extirpation of species. This is clearly not the case for state, regional or national floras in the USA where colonization (i.e. invasion by exotic species) exceeds extirpation by roughly a 24 to 1 margin. We report an alarming temporal trend in plant invasions in the Pacific Northwest over the past 100 years whereby counties highest in native species richness appear increasingly invaded over time. Despite the possibility of some increased awareness and reporting of native and exotic plant species in recent decades, historical records show a significant, consistent long-term increase in exotic species (number and frequency) at county, state and regional scales in the Pacific Northwest. Here, as in other regions of the country, colonization rates by exotic species are high and extirpation rates are negligible. The rates of species accumulation in space in multi-scale vegetation plots may provide some clues to the mechanisms of the invasion process from local to national scales. [source] Nature as historical protagonist: environment and society in pre-industrial EnglandECONOMIC HISTORY REVIEW, Issue 2 2010BRUCE M. S. CAMPBELL This article compares chronologies reconstructed from historical records of prices, wages, grain harvests, and population with corresponding chronologies of growing conditions and climatic variations derived from dendrochronology and Greenland ice-cores. It demonstrates that in pre-industrial, and especially late medieval, England, short-term environmental shocks and more enduring shifts in environmental conditions (sometimes acting in concert with biological agencies) exercised a powerful influence upon the balance struck between population and available resources via their effects upon the reproduction, health and life expectancy of humans, crops, and livestock. Prevailing socio-economic conditions and institutions, in turn, shaped society's susceptibility to these environmental shocks and shifts. [source] Hourly surface wind monitor consistency checking over an extended observation periodENVIRONMETRICS, Issue 4 2009Scott Beaver Abstract A consistency checking methodology is presented to aid in identifying biased values in extended historical records of hourly surface wind measurements obtained from a single station. The method is intended for screening extended observation periods for values which do not fail physical consistency checks (i.e., standard or complex quality assurance methods), yet nonetheless exhibit statistical properties which differ from the bulk of the record. Several specific types of inconsistencies common in surface wind monitoring datasets are considered: annual biases, unexpected values, and discontinuities. The purely empirical method checks for self-consistency in the temporal distribution of the wind measurements by explicitly modeling the diurnal variability. Each year of data is modeled using principal component analysis (PCA) (or empirical orthogonal functions, EOF), then hierarchical clustering with nearest neighbor linkage is used to visualize any annual biases existing in the measurements. The diurnal distributions for wind speed and direction are additionally estimated and visualized to determine any periods of time which are inconsistent with the typical diurnal cycle for a given monitor. The robust consistency checking method is applied to a set of 44 monitors operating in the San Joaquin Valley (SJV) of Central California over a 9-year period. Monitors from the SLAMS, CIMIS, and RAWS networks are considered. Similar inconsistencies are detected in all three networks; however, network-specific types of inconsistencies are found as well. Copyright © 2008 John Wiley & Sons, Ltd. [source] A Bayesian hierarchical extreme value model for lichenometryENVIRONMETRICS, Issue 6 2006Daniel Cooley Abstract Currently, there is a tremendous scientific research effort in the area of climate change. In this paper, our motivation is to improve the understanding of historical climatic events such as the Little Ice Age (LIA), a period of relatively cold weather around 1450,1850 AD. Although the LIA is well documented in Europe, its extent and timing are not known in areas of the globe where climatological records were not kept during this period. To study the climate, which predates historical records, proxy climate records must be used. A proxy record for the timing of climatic cooling events are the ages of the moraines left behind by glacial advances. Unfortunately, to determine the ages of these moraines in alpine environments there is little material available but lichens. Hence, lichenometry was developed to determine the ages of glacial landforms by using lichen measurements. To our knowledge, this article provides the first attempt at deriving a comprehensive statistical model for lichenometry. Our model foundation is based on extreme value theory because only the largest lichens are measured in lichenometry studies. This application is novel to extreme value theory because the quantities of interest (the ages of climatic events) are not the measured quantities (lichen diameters), i.e., it is a inverse problem. We model the lichen measurements with the generalized extreme value (GEV) distribution, upon which a Bayesian hierarchical model is built. The hierarchical model enables estimation of the hidden covariate ages of the moraines. The model also allows for pooling of data from different locations and evaluation of spatial differences in lichen growth. Parameter inference is obtained using a straightforward Markov Chain Monte Carlo method. Our procedure is applied to data gathered from the Cordillera Real region in Bolivia. Copyright © 2006 John Wiley & Sons, Ltd. [source] Ocean transport paths for the early life history stages of offshore-spawning flatfishes: a case study in the Gulf of AlaskaFISH AND FISHERIES, Issue 1 2008Kevin M Bailey Abstract Offshore- and deepwater-spawning flatfish species face the problem of transport of their planktonic stages to shallow juvenile nursery grounds that are often far shoreward in bays or estuaries. We compare life history attributes of four offshore-spawning flatfish species in the Gulf of Alaska: Pacific halibut (Hippoglossus stenolepis), arrowtooth flounder (Atheresthes stomias), rex sole (Glyptocephalus zachirus) and Dover sole (Microstomus pacificus) to examine how their larvae get from a spawning location at the edge or beyond the continental shelf to specific inshore nursery zones. We utilize historical records of survey catches of different life stages to characterize the stage-specific changes in distribution of spawning, planktonic stages and juvenile nursery areas. We infer transport mechanisms based on the shifts in distribution of the life stages and in comparison with local physical oceanography. This comparison provides insight into the different mechanisms marine species may use to solve the common ,problem' of planktonic drift and juvenile settlement. [source] Tectonic environments of ancient civilizations in the eastern hemisphereGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 5 2008Eric R. Force The map distribution of ancient civilizations shows a remarkable correspondence with tectonic boundaries related to the southern margin of the Eurasian plate. Quantification of this observation shows that the association is indeed significant, and both historical records and archaeoseismological work show that these civilizations commonly suffered earthquake damage. Close association of ancient civilizations with tectonic activity seems to be a pattern of some kind. In the hope that dividing the civilizations into subsets might clarify the meaning of this relation, primary and derivative civilizations were compared. Derivative civilizations prove to be far more closely related to the tectonic boundaries. Similarly, the civilizations that endured the longest (and that have been described as most static) are systematically the farthest from plate boundaries. It is still unclear how the relation actually worked in ancient cultures, i.e., what aspects of tectonism promoted complexity. Linkages to water and other resources, trade (broadly construed), and societal response seem likely. Volcanism appears not to be involved. © 2008 Wiley Periodicals, Inc. [source] Hydrogeologic controls on streamflow sensitivity to climate variationHYDROLOGICAL PROCESSES, Issue 22 2008Anne Jefferson Abstract Climate models project warmer temperatures for the north-west USA, which will result in reduced snowpacks and decreased summer streamflow. This paper examines how groundwater, snowmelt, and regional climate patterns control discharge at multiple time scales, using historical records from two watersheds with contrasting geological properties and drainage efficiencies. In the groundwater-dominated watershed, aquifer storage and the associated slow summer recession are responsible for sustaining discharge even when the seasonal or annual water balance is negative, while in the runoff-dominated watershed subsurface storage is exhausted every summer. There is a significant 1 year cross-correlation between precipitation and discharge in the groundwater-dominated watershed (r = 0·52), but climatic factors override geology in controlling the inter-annual variability of streamflow. Warmer winters and earlier snowmelt over the past 60 years have shifted the hydrograph, resulting in summer recessions lasting 17 days longer, August discharges declining 15%, and autumn minimum discharges declining 11%. The slow recession of groundwater-dominated streams makes them more sensitive than runoff-dominated streams to changes in snowmelt amount and timing. Copyright © 2008 John Wiley & Sons, Ltd. [source] Validation of hydrological models for climate scenario simulation: the case of Saguenay watershed in QuebecHYDROLOGICAL PROCESSES, Issue 23 2007Yonas B. Dibike Abstract This paper presents the results of an investigation into the problems associated with using downscaled meteorological data for hydrological simulations of climate scenarios. The influence of both the hydrological models and the meteorological inputs driving these models on climate scenario simulation studies are investigated. A regression-based statistical tool (SDSM) is used to downscale the daily precipitation and temperature data based on climate predictors derived from the Canadian global climate model (CGCM1), and two types of hydrological model, namely the physically based watershed model WatFlood and the lumped-conceptual modelling system HBV-96, are used to simulate the flow regimes in the major rivers of the Saguenay watershed in Quebec. The models are validated with meteorological inputs from both the historical records and the statistically downscaled outputs. Although the two hydrological models demonstrated satisfactory performances in simulating stream flows in most of the rivers when provided with historic precipitation and temperature records, both performed less well and responded differently when provided with downscaled precipitation and temperature data. By demonstrating the problems in accurately simulating river flows based on downscaled data for the current climate, we discuss the difficulties associated with downscaling and hydrological models used in estimating the possible hydrological impact of climate change scenarios. Copyright © 2007 John Wiley & Sons, Ltd. [source] Development of a New Comprehensive Ocean Atlas for Indian Ocean utilizing ARGO DataINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 2 2010B. Prasad Kumar Abstract The World Ocean Atlas (WOA), also termed ,Levitus Climatology', is a global ocean climatology containing monthly, seasonal and annual means of temperature (T) and salinity (S) fields at standard ocean depths. The monthly climatology for T and S is available for standard depths up to 1000 m. The database used in the preparation of this climatology (WOA) are historical records of Conductivity, Temperature and Depth (CTD) casts and other available marine observations collected in the past. The methodology used in preparation of this WOA is objective analysis which is essentially non-synoptic and widely scattered in the space domain. We understand that ARGO data has so far not been blended with WOA, nor has its impact for improving WOA climatology been attempted. Presently, with the wealth of marine data from ARGO profilers in the Indian Ocean, we propose a new approach to reconstruct T and S fields optimally utilizing the ARGO data. Here we develop a new model using Delaunay Tessellation with QHull algorithm delivering three-dimensional T and S fields from a non-uniform scattered database up to a depth of 1000 m. For gaps in a data-sparse region, we use all available quality-checked Ocean Station Data (OSD) and Profiling Float Data (PFL) information on T and S, in addition to the existing ARGO data. The initiative here was to replace WOA data points with realistic information from ARGO and in situ data, thereby producing a new climatology atlas. We demonstrate the robustness of our approach, and the final climatology on T and S is better compared with the existing state-of-the-art WOA. The advantage of the proposed methodology is the scope of improving the ocean atlas with the addition of more ARGO data in the near future. The clustered approach in modelling enables ocean parameter retrieval in geometrically disconnected regions with an option for hot restart. We believe that the new climatology will benefit the research community immensely. Copyright © 2009 Royal Meteorological Society [source] | ||||||||||||||||||||||||||||