bluuebunny/crossref_metadata_2025 huggingface dataset:
A Hamiltonian Approach for Tsallis Thermostatistics
Authors: Andrade J. S. de , Almeida M. P.
Published: November 2020

Since the pioneering work of Tsallis in 1988 [15] in which a nonextensive generalization of the Boltzmann-Gibbs (BG) formalism for statistical mechanics was proposed, intensive research has been dedicated to the development of the conceptual framework behind this new thermodynamical approach and to its application to realistic physical systems. In order to justify the Tsallis generalization, it has been frequently argued that the BG statistical mechanics has a domain of applicability restricted to systems with short-range interactions and non-(multi)fractal boundary conditions [14]. Moreover, it has been recalled that anomalies displayed by mesoscopic dissipative systems and strongly non- Markovian processes represent clear evidence of the departure from BG thermostatistics. These types of arguments have been duly reinforced by recent convincing examples of physical systems that are far better described in terms of the generalized formalism than in the usual context of the BG thermodynamics (see Tsallis [14] and references therein). It thus became evident that the intrinsic nonlinear features present in the Tsallis formalism that lead naturally to power laws represent powerful ingredients for the description of complex systems. In the majority of studies dealing with the Tsallis thermostatistics, the starting point is the expression for the generalized entropy Sq, where A; is a positive constant, q a parameter, and / is the probability distribution. Under a different framework, some interesting studies [8] have shown that the parameter q can be somehow linked to the system sensibility on initial conditions. Few works have been committed to substantiate the form of entropy (1) in physical systems based entirely on first principles [1, 13]. For example, it has been demonstrated that it is possible to develop dynamical thermostat schemes that are compatible with the generalized canonical ensemble [12].
Temperature Fluctuations and Mixtures of Equilibrium States in the Canonical Ensemble
Authors: Touchette Hugo
Published: November 2020

It has been suggested recently that "Q-exponential" distributions, which form the basis of Tsallis' nonextensive thermostatistical formalism, may be viewed as mixtures of exponential (Gibbs) distributions characterized by a fluctuating inverse temperature. In this chapter, we revisit this idea in connection with a detailed microscopic calculation of the energy and temperature fluctuations present in a finite vessel of perfect gas thermally coupled to a heat bath. We find that the probability density related to the inverse temperature of the gas has a form similar to a x2 density, and that the "mixed" Gibbs distribution inferred from this density is non-Gibbsian. These findings are compared with those obtained by a number of researchers who worked on mixtures of Gibbsian distributions in the context of velocity difference measurements in turbulent fluids as well as secondary distributions in nuclear scattering experiments…. Most, if not all, textbooks on thermodynamics and statistical physics define temperature as being a quantity which, contrary to other thermodynamic observables like energy or pressure, does not admit fluctuations. Because of that, it is somewhat surprising to see papers with the expression "temperature fluctuations" in their titles appearing from time to time in serious scientific journals on subjects as various as particle physics and fluid dynamics (see, e.g., Ashkenazi and Steinberg [3], Ching [9], Chiu et al. [10], and Stodolsky [24]). Indeed, how can the temperature of a system, however small, fluctuate if one defines it "as equal to the temperature of a very large heat reservoir with which the system is in equilibrium and in thermal contact" [18]? Also, in the case of the reservoir, how can temperature be a fluctuating parameter if its definition requires one to assume the thermodynamic limit, in other words, to assume that the system acting as a reservoir is composed of an infinite number of particles or degrees of freedom? Presumably, the thermodynamic limit should rule out any fluctuations of thermodynamic quantities like the mean energy or the pressure, so that if temperature is related to these quantities, how can it fluctuate?
Power-Law Persistence in the Atmosphere: An Ideal Test Bed for Climate Models
Authors: Bunde Armin , Eichner Jan
Published: November 2020

We review recent results on the appearance of long-term persistence in climatic records and their relevance for the evaluation of global climate models and rare events. The persistence can be characterized, for example, by the correlation C(s) of temperature variations separated by s days. We show that, contrary to previous expectations, C(s) decays for large s as a power law, C(s) ~ s- γ. For continental stations, the exponent γ is always close to 0.7, while for stations on islands γ ≌ 0.4. In contrast to the temperature fluctuations, the fluctuations of the rainfall usually cannot be characterized by long-term power-law correlations but rather by pronounced short-term correlations. The universal persistence law for the temperature fluctuations on continental stations represents an ideal (and uncomfortable) test-bed for the state-of-the-art global climate models and allows us to evaluate their performance. In addition, the presence of long-term correlations leads to a noval approach for evaluating the statistics of rare events. The persistence of weather states on short terms is a well-known phenomenon: a warm day is more likely to be followed by a warm day than by a cold day and vice versa. The trivial forecast that the weather of tomorrow is the same as the weather of today was, in previous times, often used as a "minimum skill" forecast for assessing the usefulness of short-term weather forecasts. The typical time scale for weather changes is about one week, a time period which corresponds to the average duration of so-called "general weather regimes" or "Grosswetterlagen," so this type of short-term persistence usually stops after about one week. On larger scales, other types of persistence occur, one of them is related to circulation patterns associated with blocking [5]. A blocking situation occurs when a very stable high-pressure system is established over a particular region and remains in place for several weeks. As a result, the weather in the region of the high remains fairly persistent throughout this period. Furthermore, transient low-pressure systems are deflected around the blocking high so that the region downstream of the high experiences a larger than usual number of storms.
Network Concepts, Measures, and the Multitheoretical, Multilevel Analytic Framework
Authors: Monge Peter R. , Contractor Noshir
Published: November 2020

This chapter begins with an overview of network analysis concepts and measures. Those readers who are new to the area, or who are familiar with the social theories described in this book but not with network analysis itself, should find a careful reading of the first section of this chapter to be essential in understanding the remainder of the chapter and book. Network analysis has become a fairly technical topic, and there are a number of concepts, measures, and analytic strategies that require careful explication. This section of the chapter should provide sufficient background in network analysis to enable an informed reading of the network literature. We hasten to emphasize, however, that it is only a brief introduction. Hence, like all other introductory materials, an attempt is made to trade-off conceptual rigor with simplicity. An extensive literature exists on network analysis, including several fine texts and a number of excellent review chapters. Those who wish to explore further the network analysis material presented in the first third of this chapter should consult the sources in the references that we have identified under “Relations in a World of Attributes.” Those who are more familiar with network analysis will find the first section of this chapter less important. A quick skim should provide ample insight into our selection and use of concepts and definitions. The second section introduces the MTML framework. It shows how various network properties at different levels of analysis can represent the generative mechanisms from different social theories. It also shows how combining theories can provide broader explanations of emergent networks than each theory can alone. As a part of that framework we introduce the statistical ideas pertaining to realizations of a graph and discuss p* analytic strategies and the PSPAR computer program that can be used to analyze relevant data. This section concludes with an extended presentation of the MTML model, which broadly classifies variables into endogenous and exogenous factors, each with multiple levels. Examples are provided for each of the ten classes of hypotheses generated by this framework.
Exchange and Dependency Theories
Authors: Monge Peter R. , Contractor Noshir
Published: November 2020

Extensive research has been conducted that seeks to explain the emergence of networks based on exchange and dependency mechanisms. Social exchange theory, originally developed by Romans (1950, 1974) and Blau (1964), seeks to explain human action by a calculus of exchange of material or information resources. In its original formulation, social exchange theory attempted to explain the likelihood of a dyadic relationship based on the supply and demand of resources that each member of the dyad had to offer. Emerson (1962, 1972a, 1972b) extended this original formulation beyond the dyad, arguing that in order to examine the potential of exchange and power-dependence relationships, it was critical to examine the larger network within which the dyad was embedded. Since then several scholars have developed this perspective into what is now commonly referred to as network exchange theory (Bienenstock & Bonacich, 1992, 1997; Cook, 1977, 1982; Cook & Whitmeyer, 1992; Cook & Yamagishi, 1992; Markovsky, Wilier, & Patton, 1988; Skvoretz & Wilier, 1993; Wilier & Skvortez, 1997; Yamagishi, Gillmore, & Cook, 1988). Network exchange theory posits that the bargaining power of individuals is a function of the extent to which they are vulnerable to exclusion from communication and other exchanges within the network. The argument is that individuals forge network links on the basis of their analysis of the relative costs and returns in exchanging their investments with others in the network. This is in contrast with theories of self-interest where actors seek to maximize their individual investments independent of its exchange value. Likewise, individuals maintain links based on the frequency, the uncertainty, and the continuing investments to sustain the interaction. Location in the network may confer on some people an advantage over others in engaging in exchange relationships. Aldrich (1982) notes that this argument is at the core of several theories dealing with social exchange as well as resource dependence theories. Within organizations, network researchers have proposed a social exchange mechanism for the study of (1) power, (2) leadership, and (3) trust and ethical behavior. At the interorganizational level, researchers have (1) tested resource dependence theory, (2) examined the composition of corporate elites and interlocking board of directorates, and (3) sought to explain the creation, maintenance, and dissolution of interorganizational links.
Homophily, Proximity, and Social Support Theories
Authors: Monge Peter R. , Contractor Noshir
Published: November 2020

This chapter discusses three families of theoretical mechanisms—homophily, proximity (physical and electronic), and social support—that have been identified by social scientists as important motivations for why we create, maintain, dissolve, and reconstitute our communication networks. While much of this research is conducted in nonorganizational settings, this chapter focuses on the theory and research that we consider to be most germane to communication and other organizational networks. Several researchers have attempted to explain communication networks on the basis of homophily, that is, the selection of others who are similar. Brass (1995a, p. 51) notes that “similarity is thought to ease communication, increase predictability of behavior, and foster trust and reciprocity.” Homophily has been studied on the basis of similarity in age, gender, education, prestige, social class, tenure, and occupation (Carley, 1991; Coleman, 1957; Ibarra, 1993b, 1995; Laumann, 1966; Marsden, 1988; McPherson & Smith-Lovin, 1987). Several lines of reasoning provide support for the homophily hypothesis. These fall into two general categories: the similarity-attraction hypothesis (Byrne, 1971) and the theory of self-categorization (Turner, 1987). The similarity-attraction hypothesis is exemplified in the work of Heider (1958) who posited that homophily reduces the psychological discomfort that may arise from cognitive or emotional inconsistency. Similarly, Sherif (1958) suggested that individuals were more likely to select similar others because by doing so they reduce the potential areas of conflict in the relationship. The theory of self-categorization (Turner & Oakes, 1986) suggests that individuals define their social identity through a process of self-categorization during which they classify themselves and others using categories such as age, race, gender. Schachter (1959) argued that similarity provided individuals with a basis for legitimizing their own social identity. The manner in which individuals categorize themselves influences the extent to which they associate with others who are seen as falling into the same category. It is easy to see that the theoretical mechanism by which homophily influences the likelihood of a communication relation is based on the similarity among specific attributes of the actors.
Trace Metal Cycling
Authors: Bianchi Thomas S.
Published: November 2020

Like many other elements, natural background levels of trace elements exist in crustal rocks, such as shales, sandstones, and metamorphic and igneous rocks (Benjamin and Honeyman, 2000). In particular, the majority of trace metals are derived from igneous rocks, simply based on the relative fraction of igneous rocks in comparison with sedimentary and metamorphic rocks in the Earth’s crust. The release of trace metals from crustal sources is largely controlled by the natural forces of physical and chemical weathering of rocks, notwithstanding large-scale anthropogenic disturbances such as mining, construction, and coal burning (release of fly ash). As discussed later in the chapter, adjustments can be made for anthropogenic loading to different ecosystems based on an enrichment factor which compares metal concentrations in the ecosphere to average crustal composition. Biological effects of weathering, such as plant root growth and organic acid release associated with respiration also contribute to these weathering processes. As some trace metals are more volatile than others, release due to volcanic activity represents another source of metals with such properties (e.g., Pb, Cd, As, and Hg). Just as Goldschmidt (1954) grouped elements (e.g., siderophiles, chalcophiles, lithophiles, andatomophiles) based on similarities in geochemical properties, trace metals also represent a group of elements with similar chemical properties. One particularly important distinguishing feature of these elements is their ability to bond reversibly to a broad spectrum of compounds (Benjamin and Honeyman, 2000). Thus, the major inputs of trace metals to estuaries are derived from riverine, atmospheric, and anthropogenic sources. Although trace elements typically occur at concentrations of less than 1 ppb (part per billion) (or μg L−1, also reported in molar units), these elements are important in estuaries because of their toxic effects, as well as their importance as micronutrients for many organisms. The fate and transport of trace elements in estuaries are controlled by a variety of factors ranging from redox, ionic strength, abundance of adsorbing surfaces, and pH, just to name a few (Wen et al., 1999).
The Grand Tour
Authors: Fagan Brian
Published: November 2020

While many English archaeological travelers visited Avebury, Stonehenge, and other monuments at home, the more affluent traveled the classical lands. By the eighteenth century, the so-called “grand tour,” a leisurely journey through Europe, became an essential part of a gentleman’s education. Typically, the oldest son of a well-off family went abroad to complete his education, often with a tutor both to instruct and to keep an eye on his charge: “If a young man is wild, and must run after women and bad company, it is better he should do so abroad.” At first these tours were a form of education for courtiers and career diplomats, meant to train a young gentleman to take his place in a world where mere patriotism was not enough. But they soon became a kind of finishing school for the aristocracy. “Sir,” pronounced Dr. Samuel Johnson, “a man who has not been to Italy is always conscious of an inferiority, from his not having seen what it is expected a man should see. The grand object of travelling is to see the shores of the Mediterranean.” Until the late sixteenth century, the journey through Europe was both dangerous and uncomfortable, thanks to bandits, smallpox epidemics, robbers, and appalling conditions on the road. There was also a danger of being seized by the Inquisition as a Protestant, especially at Easter, when the authorities watched for those who failed to take the sacrament. In 1592 and 1595, the pope complained at the number of English heretics who traveled to Venice. Travel for pleasure was by this time fashionable. By 1700, the grand tour had become the ideal way of imparting taste and knowledge into the minds of ignorant youths who would otherwise indulge in unbridled debauchery. There were bound to be numerous hazards and mishaps along the way for the long sightseer. Guidebooks provided (usually inaccurate) maps and directions to hotels along the post routes. The Gentleman’s Pocket Companion for Travelling into Foreign Parts, first published in 1722, laid out a delicious, if hazardous, scenario of what could happen at an inn.
Introduction
Authors: Berger Antony R.
Published: November 2020

This volume is a contribution to the new and rapidly expanding field of medical geology that links geologists and other earth scientists with plant and animal biologists and medical, dental, and veterinary specialists in efforts to resolve local and global health issues. The topics mentioned range from the health effects of arsenic, mercury, and fibrous minerals, natural hazards that contribute to the etiology of endemic diseases, to questions on the identification of such hazards. Medical geology aims to strengthen and integrate research that can reduce environmental threats to the health and well-being of humans and animals. It embraces disciplines as diverse as mineralogy and pathology (Geology and Health 2001, Geosciences and Human Health 2001). Health generally refers to people and other living creatures, whereas the focus of geology is on the inanimate and the distant past. Although these may be separate arenas or compartments for investigations, the direct links are hard to ignore. Life itself has evolved within a matrix of earth materials — rocks, minerals, soils, water, air — the availability of which has a profound control on what all living creatures ingest and how they develop, both biologically and culturally. The air we breathe, the water we drink, and the nutrients we consume depend on the geological environment that we can only partially control. As we struggle to cope in a world rushing toward 10 billion people, a better understanding of the ways in which the natural environment influences our health should permit more intelligent decisions for the future. The general consensus concerning global change recognizes that humans have had a powerful impact on their surroundings. The other side to that relationship — the sometimes harmful effects of geological materials and processes on us — is the subject of this volume. Combining knowledge and expertise from the earth sciences with that from the medical and life sciences has numerous applications to the resolution of health issues. Coordinating efforts can sharpen the definition of a problem, aid in strategies of reclamation, define and locate sources of potable water, and develop economical solutions based on geological principles that can help to ease, if not prevent, suffering and disease.
Human Geophagy: A Review of Its Distribution, Causes, and Implications
Authors: Abrahams Peter W.
Published: November 2020

Geophagy (or geophagia) can be defined as the habit of eating clay or earth, a practice about which there is a great deal of misunderstanding. Though many people know and accept that geophagy is undertaken by wild and domesticated animals, and that humans can inadvertently ingest soil by (for example) hand-to-mouth activity, the deliberate consumption of soil by humans appears to be more difficult to comprehend. Yet geophagy (or pica) is a widespread among contemporary nonhuman primates (Krishnamani and Mahaney 2000), suggesting that the practice predates human evolution, and that soil ingestion has continued for a multiplicity of reasons. Therefore, although words such as ‘evil,’ ‘odd,’ ‘filthy’ and ‘degrading’ have been applied to geophagy as practiced by humans, a more enlightened appraisal is to suggest that soil consumption should be considered to be within the normal range of human behavior (Vermeer 1986). The oldest evidence for human geophagy comes from a prehistoric site at Kalambo Falls where the bones of Homo habilis, the immediate predecessor of Homo sapiens, have been found alongside a white clay believed to have been used for geophagical purposes (Root-Bernstein and Root- Bernstein 2000). Human migration then transferred geophagy to other parts of the earth, although Laufer (1930) concluded that the practice is not universal, being unknown in some countries such as Japan, Korea, and parts of Africa. To a certain extent this may be attributable to a lack of reporting on geophagy. For example, although the practice is not recorded in Namibia by Lagercrantz (1958, Figure 1),Thomson (1997) reports that the deliberate consumption of soil is commonly undertaken by pregnant women in the eastern Caprivi region of the country. Geophagy can still be found relatively easily throughout many societies of the world today. While investigating geohelminth (i.e., parasitic worm) infection and mineral nutrient deficiencies in children and pregnant women, Geissler et al. (1997, 1998) indicated the prevalence of geophagy in parts of Kenya. In these studies, 73% of 285 school children aged 5-18 years indulged in the practice, whereas 154 of 275 pregnant women (56%) reported eating soil regularly.
Environmental Iodine in Iodine Deficiency Disorders, with a Sri Lankan Example
Authors: Fordyce Fiona M. , Johnson Chris C.
Published: November 2020

Iodine is an essential element for human and other animal health and forms an important constituent of the thyroid hormones thyroxine (T4, also known as tetraiodothyronine) and triiodothyronine (T3). These hormones play a fundamental biological role in controlling growth and development (Hetzel and Maberly 1986). If the amount of utilizable iodine reaching the thyroid gland is inadequate, or if thyroid function is impaired, hormone production can be reduced, resulting in a group of conditions collectively referred to as Iodine Deficiency Disorders (IDD) (Fernando et al. 1987, Hetzel 1989). The World Health Organization (WHO 1993) estimate that in excess of one billion people worldwide are at risk from IDD, the most common manifestation of which is goiter (Fig. 9.1). Iodine deficiency is the world’s most common cause of preventable mental retardation and brain damage, and has a significant negative impact on the social and economic development of communities. Although it is likely that IDD are multifactorial diseases involving other trace element deficiencies and goitrogens (goiter-promoting substances) in foodstuffs, a lack of adequate dietary iodine remains a major concern (Stewart and Pharaoh 1996). The link between environmental iodine and IDD has been known for the last 80 years. During this time, the medical community has become well organized when tackling the problem, exemplified by the work of the International Council for the Control of IDD (ICCIDD) ( ), which provides an excellent dissemination point for discussion and information. Remediation strategies often focus on enhancing dietary intakes of iodine via the introduction of iodinated salt and iodinated oil programs (Stanbury and Hetzel 1980). However, these methods are not always successful and other strategies, including environmental interventions, require development (DeLong et al. 1997) In contrast to the wealth of information about the symptoms, assessment, and treatment of IDD, there is very little on the primary cause, a lack of readily available iodine in the environment and diet. Our knowledge of environmental iodine geochemistry is limited, mainly because the analytical methods for assessment are not routine and iodine is not an element that has been systematically determined in geochemical surveys. However, in the past two decades, improved analytical methodologies and an interest in iodine from different perspectives have added much to our knowledge.
Life in a Copper Province
Authors: Robbins Eleanora I. , Harthill Michalann
Published: November 2020

The North American Lake Superior region contains a world-class copper province nearly 300,000 km² in area. A dozen major copper deposits and hundreds of smaller mineral accumulations are located in Michigan, Minnesota, and Ontario (Morey and Sims 1996), many of which include As, nickel (Ni), platinum (Pt), palladium (Pd), Co, Mo, and Fe, as well as Cu (Nicholson et al. 1992). Historically, the province has hosted a variety of life forms; fossil biota have been traced as far back as 2.6-2.75 Ga. Palynological and microbial research (Robbins 1985, Robbins et al. 1994) prompts speculation about possible correlations between copper and the biota that evolved there. Because the region has been subjected to continental collisions, volcanism, glaciation, rifting, weathering, sea level rise and fall, waxing and waning of lakes, soil formation, and now to human settlement and development including mining, the fossil record is discontinuous. This review of the geologic formations in the Lake Superior region from the Precambrian to the present, and their copper and biotic occurrences and associations, attempts to illuminate some of those geologic/ biologic correlations, and includes mention of modern environmental concerns. Copper is one of nearly 75 chemical elements contributing to metabolic or structural functions of organisms (Dexter-Dyer et al. 1984). Bioassimilation varies and depends not only on availability from the environment, but also on the species, gender, and age of organism with specific concentrations also depending on diet, health, tissue assayed, and various synergisms with other trace elements such as Fe and Zn. Indeed, copper is an essential element and co-factor contributing to copper-associated polypeptides that provide catalytic and electron transfer functions in almost every known group of organisms alive today, from bacteria to humans. Copper proteins contribute to skin pigmentation, nerve coverings, and in mechanisms of development, maintenance, and repair of connective tissues important for well-functioning cardiovascular systems (Eisler 2000). Presently, over two dozen essential copper proteins, some with porphyrin-copper functional groups (similar to the porphyrin-iron association in hemoglobin), have been identified, each with its specific developmental or physiological function (Cowan 1998).
Amazonian Landscapes : Gender, War, and Historical Repetition
Authors: Dowler Lorraine
Published: November 2020

It has been speculated that legends and myths are usually born out of everyday life. Surprisingly, it could be argued that the legend of the Amazons mirrors contemporary life in that women who actively participate in warfare are considered “out of place” with the normative landscape. As Enloe argues, the Amazonian world is a place apart, where gender roles are inverted, or worse, “what is wrong about the Amazons is not only that they are women who fight using military equipment and tactics, but that they live without men.” However, unlike the Amazons, Western societies are comforted by men being the soldiers, warriors, and heroes of war, while women are either victims or seraphic icons of war. As a society, we are consoled by nurturing images of women in the role of nurses on the battlefield or, most important, as champions of the home front. Cock contends that when people go to war, they do so specifically as men and women, rather than in nationalist solidarity. She argues that the military, as a masculine power structure, actually magnifies how masculinity and femininity are defined within society. This seems to hold constant even in the exceptional case of the Amazons. Many feminists argue that throughout history representations of these female warriors have been dichotomous in nature. On the one hand, Amazonian images mark women’s emotional and physical strength while simultaneously rendering them erotic, thereby reinforcing men’s virility. As Kleinbaum argued, “As surely as no spider’s web was built for the glorification of flies, the Amazon idea was not designed to enhance women.” In his book War and Gender Goldstein details some popular representations of the myth to illustrate this point. In the 1931 play The Warrior’s Husband, Katharine Hepburn’s portrayal of the warrior queen Antiope radically challenged contemporary understandings of gender roles of her time. However, the play’s reviews overlooked these questions of identity in favor of essentializing Hepburn’s body with such statements as the play where “she first bared her lovely legs.”
Dynamic Metageographies of Terrorism : The Spatial Challenges of Religious Terrorism and the “War on Terrorism”
Authors: flint colin
Published: November 2020

Smoke pluming from the towers of the World Trade Center and a mushroom cloud resulting from a “bunker-buster” bomb dropped on a presidential palace of Saddam Hussein: the two related images suggest that the geopolitics of the twenty-first century will be very much about the “shock and awe” of terrorism. Terrorism and counter-terrorism are both geopolitical in that they utilize and attempt to change geographic structures for political ends. By examining the geographic components in definitions of terrorism, we can understand how changes in the geographic scope of terrorist activity are useful in explaining the changing motivations and implications of terrorism. The rise of terrorism motivated by religious ideologies is especially central to questions of how the geography and goals of terrorism are changing. In addition, states, especially the United States of America, have come to define terrorism as a matter of global geopolitics rather than domestic policing. However, a focus upon the geography of counterterrorism suggests that there is a geographic mismatch between the organization of terrorists and the spatial means and goals of governments. In a word, states still rely upon the control of sovereign territory to counter terrorist networks. This too has implications for future conflict. Since the attacks of September 11, 2001, there has been a deluge of essays, analysis, and political punditry, often intertwined or disguised, on the topic of terrorism. The justification of another essay must rest on the possibility of further insight. Academic geography is a perspective rather than a defined subject matter, and I hope to use its key concepts to provide new ways of understanding the motivations behind contemporary terrorist acts, the geopolitics of antiterrorism, and its negative political geographic implications. Specifically, three geographic concepts are integrated into my argument, and I identify the importance of another that others are more qualified to discuss. First, the concept of geohistorical context is useful in identifying the complexities of the temporal and spatial influences upon, and of, terrorism. For example, the attacks of September 11, 2001, were simultaneously of that hour and of the past and present century.
Conflict at the Interface : The Impact of Boundaries and Borders on Contemporary Ethnonational Conflict
Authors: Newman David
Published: November 2020

Boundaries may have become more permeable than in the past, but they remain the hard lines that determine the territorial extent of the state and, by definition, the citizenship of those residing therein. Notwithstanding the discourse of deterritorialization and the “end of the state,” the hard boundaries that separate states in the international system remain important delimiters of power and partial sovereignty in the contemporary world. The relative impact of these boundaries on the surrounding borderland regimes has changed, in many cases to allow greater movement of people, goods, information, and cultural exchanges. But the impact of these changes remains highly differentiated and affects some areas, such as Western Europe, far more than others, where boundaries retain their traditional role as barriers to movement and interaction. In attempting to understand these changes, boundary studies have undergone a major renaissance during the past decade. From the study of hard territorial lines and the process of boundary demarcation, contemporary research has taken on a wider range of boundary-related topics, such as territorial identities, borderlands and border regimes, the perception of boundaries, and the nature of boundary management. The analysis of boundaries has also shifted in focus from the preeminence of international boundaries to include a range of spatial and administrative intrastate scales, in which the functional impact of the boundary/border on the daily lives of people is as great as, if not greater than, the line that separates one state from another. It is the process of bordering, rather than the course of the line per se, that is important to our understanding of how boundaries affect the nature of interaction, cooperation, and/or conflict between peoples. This is part of a dynamic process in which boundaries not only reflect a given formal political or administrative status as determined by the state, but are also reformulated as a result of war, conflict resolution, negotiations, unilateral imposition, and so on. Conflict still takes place in and around boundaries and borderlands, in some cases as a result of traditional issues of demarcation with respect to territorial attributes, such as natural resources, and in others as a result of their incompatibility with the expanding horizons of identity politics.
Monitoring Agricultural Drought in Australia
Authors: Day Kenneth A. , Rickert Kenwyn G.
Published: November 2020

Since European settlement of Australia began in 1788, drought has been viewed as a major natural threat. Despite warnings by scientists (e.g., Ratcliffe, 1947) and many public inquiries, government policies have, in the past, encouraged closer land settlement and intensification of cropping and grazing during wetter periods. Not surprisingly, drought forms part of the Australian psyche and has been well described in poetry, literature (e.g., Ker Conway, 1993), art, and the contemporary media (newspapers and television). Droughts have resulted in social, economic, and environmental losses. Attitudes toward drought in Australia are changing. Government policies now consider drought to be part of the natural variability of rainfall and acknowledge that drought should be better managed both by governments and by primary producers. Nonetheless, each drought serves as a reminder of the difficult challenges facing primary producers during such times. We begin this chapter with a brief overview of drought in Australia and its impacts on agricultural production, the environment, rural communities, and the national economy. We outline some of the ways governments and primary producers plan for and respond to drought and describe in detail an operational national drought alert system. Australia has mainly an arid or semiarid climate. Only 22% of the country has rainfall in excess of 600mmper annum, confined to coastal areas to the north, east, southeast, and far southwest of the country (http://www.bom.gov.au/climate/ahead/soirain.shtml). Australia also has high year-to-year and decade-to-decade variation in rainfall due, in part, to the influence of the El Niño/Southern Oscillation (ENSO) phenomenon (http://www.bom.gov.au/climate/ahead/soirain.shtml). The Interdecadal Pacific Oscillation (IPO) also contributes to the rainfall variability at annual and decadal scales and modulates ENSO impacts on rainfall (Power et al., 1999). The current geographic boundaries of agricultural production were reached in the late 19th century, and the entire agricultural region has experienced drought, in some form, over the past 100 years. Protracted dry periods occurred during the period from late 1890s to 1902 in eastern Australia, during the mid to late 1920s and 1930s over most of the continent, during the 1940s in eastern Australia, during the 1960s over central and eastern Australia, and during 1991–95 in parts of central and northeastern Australia.
Introduction
Authors: Alexander Earl B. , Coleman Roger G. , Keeler-Wolfe Todd , Harrison Susan P.
Published: November 2020

Ultramafic, or colloquially “serpentine,” rocks and soils have dramatic effects on the vegetation that grows on them. Many plants cannot grow in serpentine soils, leaving distinctive suites of plants to occupy serpentine habitats. Plants that do grow on serpentine soils may be stunted, and plant distributions are commonly sparse relative to other soils in an area. Plant communities on serpentine soils are usually distinctive, even if one does not recognize the plant species. Because of these distinctive features, ultramafic rocks and serpentine soils are of special interest to all observers of landscapes. Geology underlies both conceptually and literally the distinctive vegetation on serpentine soils. The occurrence of special floras on particular substrates within particular regions makes rocks and soils of key significance to plant evolution and biogeography. Sophisticated interpretations of these interrelationships require a combined knowledge of geology, soils, and botany that few people possess. Even highly specialized professionals generally lack the requisite expertise in all three disciplines. The science of ecology, which in principle concerns interactions among all aspects of the environment, seldom incorporates a deep understanding of rocks and soils. Some scientists have attempted to bridge this gap through creating a discipline known as geoecology (Troll 1971, Huggett 1995), which forms the basis for our interdisciplinary exploration of serpentine rocks and soils in western North America. The term “serpentine” is applied in a general sense to all ultramafic rocks, soils developed from them, and plants growing on them. Ultramafic rocks are those with very high magnesium and iron concentrations. The word serpentine is derived from the Latin word serpentinus, meaning “resembling a serpent, or a serpent’s skin,” because many serpentine rocks have smooth surfaces mottled in shades of green to black. The distinctive chemistry of ultramafic rocks and serpentine soils restricts the growth of many plants and makes them refuges for plants that thrive in serpentine habitats, including serpentine endemics (species that are restricted to these soils) and other species that have evolved means of tolerating these habitats. Often the means of tolerance include visible adaptations such as slow growth and relatively thick, spiny foliage.
Serpentine Soil Distributions and Environmental Influences
Authors: Alexander Earl B. , Coleman Roger G. , Keeler-Wolfe Todd , Harrison Susan P.
Published: November 2020

Serpentine soils occur in all but one of the twelve orders (Alexander 2004b), which is the highest level in Soil Taxonomy (Soil Survey Staff 1999), the primary system of soil classification utilized in this book (appendix C). They occur in practically every environment from cold arctic to hot tropical and from arid to perhumid (always wet). Thus the variety of serpentine soils is very great even though they occupy only a small fraction of the earth. Serpentine soils have been found in all states and provinces that are adjacent to the Pacific Ocean from Baja California to Alaska. They are most concentrated in the California Region, where they have been mapped in 34 counties in California and in 5 counties in southwestern Oregon. Serpentine lateritic (or “nickel laterite”) soils, which have not been mapped separately from other soils, are economically significant in California and southwest Oregon, even though they are not widely distributed in western North America. A representative serpentine soil is shown in figure 6-1. Serpentine soils, or soils in magnesic (serpentine) families, are represented in 11 of the 12 soil orders. Spodosols and Histosols in magnesic families occur only where there is a thin cover of nonserpentine materials over the serpentine materials, and there are no serpentine Andisols. Andisols contain amorphous and poorly ordered aluminum-silicate minerals, which are responsible for andic soil properties of these soils. Serpentine soil parent materials do not contain enough aluminum for the development of andic soil properties that are definitive of Andisols. Alfisols are soils with argillic (or natric) horizons having more than 35% exchangeable bases (Ca2+, Mg2+, Na+, and K+) on the cation exchange complex. Al3+ and H+ are the common nonbasic (acidic) cations on the exchange complex. The Mg2+ that serpentine soil parent materials release upon weathering keeps the basic cation status of soils high, unless they are leached intensively. Some of the soil horizon sequences are A-Bt, A-Btn, and A-Bt-Btk in Alfisols. Soils of Dubakella Series and other moderately deep Mollic Haploxeralfs with a mesic soil temperature regime are the most extensively mapped serpentine Alfisols in California and southwestern Oregon. Figure 6-1 is representative of the Mollic Haploxeralfs.
Blue Mountains, Domain 6
Authors: Alexander Earl B. , Coleman Roger G. , Keeler-Wolfe Todd , Harrison Susan P.
Published: November 2020

The Blue Mountains domain is mostly in northeastern Oregon. It is the name that we and others (Orr and Orr 1996) have adopted for the Central Highlands subprovince of the Columbia Intermountain province (Freeman et al. 1945). Small areas of Blue Mountains ultramafic rocks are exposed in an arcuate trend from central Oregon through northeastern Oregon into western Idaho. They are in the Baker and Wallowa terranes (Vallier and Brooks 1995). These terranes with the ultramafic rocks are covered or surrounded by Tertiary volcanic flows, largely Columbia River basalt. The ultramafic rocks are exposed in the Canyon Mountain and Sparta complexes and in smaller areas from the edge of the Idaho Batholith near Riggins in Idaho south–southwest across northeastern Oregon to the Aldrich Mountains south of Dayville. The Snake River has cut a deep gorge through the Blue Mountains domain. At Hells Canyon it is >2000 m deep. Strawberry Mountain southeast of John Day rises to 2755 m. Ultramafic rocks are exposed from about 975 m at the foot of the Strawberry Range, near Canyon City, to 2243 m on Baldy Mountain in the Strawberry Range and a bit higher on Vinegar Hill, which is about 45 km northeast of the Strawberry Range, although the summit of Vinegar Hill (2478 m above sea level) is not composed of ultramafic rocks. Summers are hot and dry and winters are cold, with snow that persists through winters at the higher elevations. Mean annual temperatures are mostly in the 3°C–9oC range, and mean annual precipitation ranges from 25 to 100 cm. The frost-free period is about 150 days at lower elevations and <60 days at higher elevations. The ultramafic rocks were exposed by late Tertiary uplift and erosion of the overlying volcanic sequence. The older rocks are composed of a volcanic island arc complex that contains marine sediments interlayered with mafic volcanic flows. Deep erosion of this area has exposed the roots of the volcanic arc. The roots contain gabbro and peridotite–serpentine at their lowest levels. Seven-thousand-year-old volcanic ash from Mt.
Northern Cascade-Fraser River, Domain 7
Authors: Alexander Earl B. , Coleman Roger G. , Keeler-Wolfe Todd , Harrison Susan P.
Published: November 2020

The Northern Cascade–Fraser River domain conforms to the Northern Cascade Mountains physiographic province in northwestern Washington and southern British Columbia, the San Juan Islands between the southern tip of Vancouver Island and the Northern Cascade Mountains, and much of the Interior Plateau province of British Columbia. The thread that connects these areas is the north–south Straight Creek–Fraser River fault system that runs through the Northern Cascade Mountains and northward along the Fraser River. The localities of domain 7 are along faults that branch off from this major fault system. The Northern Cascade Mountains are indeed mountainous, and the Interior Plateau of British Columbia is an area of dissected plateaus and scattered mountains. The Fraser River flows northwest in the Rocky Mountain Trench, which separates the North American craton on the northeast from accreted terranes on the southwest; then it turns around the northwest end of the Cariboo Mountains to the Interior Plateau. In the Interior Plateau, the Fraser River flows from Prince George south about 500 km to the Northern Cascade Mountains before turning westward toward the Pacific Coast. The northern part of domain 7 is in that part of the Fraser River basin, including tributaries northwest of Prince George, which is in the Interior Plateau province. Low, hilly terrain dominates the San Juan Islands. All of these areas in domain 7, except the Ingalls complex on southeast margin of the Northern Cascade Mountains, were covered by the Cordilleran ice sheet during the last stage of the Pleistocene glaciation, leaving <15 ka years for soil development on the current ground surfaces. Although alpine glaciers formed in the southeastern margin of the Northern Cascade Mountains, they did not cover all of the soils, allowing some of them longer time for development. Elevations in domain 7 range from sea level on San Juan Islands to mostly in the 600–1500 m range on the Interior Plateau of British Columbia, and up to 4392 m on Mt. Rainier in the Northern Cascade Mountains.