How far from Jerusalem? Tropical customs and the question of race in the Book of John Mandeville

The Book of John Mandeville, while ostensibly a pilgrimage guide documenting an English knight’s journey into the East, is an ideal text in which to study the developing concept of race in the European Middle Ages. The Mandeville-author’s sense of place and morality are inextricably linked to each other: Jerusalem is the center of his world, which necessarily forces Africa and Asia to occupy the spiritual periphery. Most inhabitants of Mandeville’s landscapes are not monsters in the physical sense, but at once startlingly human and irreconcilably alien in their customs. Their religious heresies, disordered sexual appetites, and monstrous acts of cannibalism label them as fallen state of the European Christian self. Mandeville’s monstrosities lie not in the fantastical, but the disturbingly familiar, coupling recognizable humans with a miscarriage of natural law. In using real people to illustrate the moral degeneracy of the tropics, Mandeville’s ethnography helps shed light on the missing link between medieval monsters and modern race theory.

The occurrence of two new plankton diatom populations in the English Lake District: Aulacoseira islandica

Samples of planktonic algae from major lakes in the English Lake District have been investigated over many years as part of a long-term monitoring programme set up by the Freshwater Biological Association and continued by the Institute For Ecology. Some lakes have been sampled regularly for long periods, others less frequently or only occasionally. Windermere north and south basins, and the neighbouring lakes Blelham Tarn and Esthwaite Water, have been under observation, mostly on a weekly basis, since the programme began in 1945. During this time diatoms have played a significant role in the population dynamics of these lakes.

I. A seismotectonic study of the Middle America Subduction Zone. II. Lithosphere and upper mantle structure of the Canadian Shield and Eastern North America

This thesis consists of two separate parts. Part I (Chapter 1) is concerned with seismotectonics of the Middle America subduction zone. In this chapter, stress distribution and Benioff zone geometry are investigated along almost 2000 km of this subduction zone, from the Rivera Fracture Zone in the north to Guatemala in the south. Particular emphasis is placed on the effects on stress distribution of two aseismic ridges, the Tehuantepec Ridge and the Orozco Fracture Zone, which subduct at seismic gaps. Stress distribution is determined by studying seismicity distribution, and by analysis of 190 focal mechanisms, both new and previously published, which are collected here. In addition, two recent large earthquakes that have occurred near the Tehuantepec Ridge and the Orozco Fracture Zone are discussed in more detail. A consistent stress release pattern is found along most of the Middle America subduction zone: thrust events at shallow depths, followed down-dip by an area of low seismic activity, followed by a zone of normal events at over 175 km from the trench and 60 km depth. The zone of low activity is interpreted as showing decoupling of the plates, and the zone of normal activity as showing the breakup of the descending plate. The portion of subducted lithosphere containing the Orozco Fracture Zone does not differ significantly, in Benioff zone geometry or in stress distribution, from adjoining segments. The Playa Azul earthquake of October 25, 1981, M_s=7.3, occurred in this area. Body and surface wave analysis of this event shows a simple source with a shallow thrust mechanism and gives M_o=1.3x10²⁷ dyne-cm. A stress drop of about 45 bars is calculated; this is slightly higher than that of other thrust events in this subduction zone. In the Tehuantepec Ridge area, only minor differences in stress distribution are seen relative to adjoining segments. For both ridges, the only major difference from adjoining areas is the infrequency or lack of occurrence of large interplate thrust events.

Part II involves upper mantle P wave structure studies, for the Canadian shield and eastern North America. In Chapter 2, the P wave structure of the Canadian shield is determined through forward waveform modeling of the phases P_nl, P, and PP. Effects of lateral heterogeneity are kept to a minimum by using earthquakes just outside the shield as sources, with propagation paths largely within the shield. Previous mantle structure studies have used recordings of P waves in the upper mantle triplication range of 15-30°; however, the lack of large earthquakes in the shield region makes compilation of a complete P wave dataset difficult. By using the phase PP, which undergoes triplications at 30-60°, much more information becomes available. The WKBJ technique is used to calculate synthetic seismograms for PP, and these records are modeled almost as well as the P. A new velocity model, designated S25, is proposed for the Canadian shield. This model contains a thick, high-Q, high-velocity lid to 165 km and a deep low-velocity zone. These features combine to produce seismograms that are markedly different from those generated by other shield structure models. The upper mantle discontinuities in S25 are placed at 405 and 660 km, with a simple linear gradient in velocity between them. Details of the shape of the discontinuities are not well constrained. Below 405 km, this model is not very different from many proposed P wave models for both shield and tectonic regions.

Chapter 3 looks in more detail at recordings of P_nl in eastern North America. First, seismograms from four eastern North American earthquakes are analyzed, and seismic moments for the events are calculated. These earthquakes are important in that they are among the largest to have occurred in eastern North America in the last thirty years, yet in some cases were not large enough to produce many good long-period teleseismic records. A simple layer-over-a-halfspace model is used for the initial modeling, and is found to provide an excellent fit for many features of the observed waveforms. The effects on P_nl of varying lid structure are then investigated. A thick lid with a positive gradient in velocity, such as that proposed for the Canadian shield in Chapter 2, will have a pronounced effect on the waveforms, beginning at distances of 800 or 900 km. P_nl records from the same eastern North American events are recalculated for several lid structure models, to survey what kinds of variations might be seen. For several records it is possible to see likely effects of lid structure in the data. However, the dataset is too sparse to make any general observations about variations in lid structure. This type of modeling is expected to be important in the future, as the analysis is extended to more recent eastern North American events, and as broadband instruments make more high-quality regional recordings available.

The ionic composition of surface waters in the English Lake District, related to bedrock geology, with some singular facts and speculation on the existence of mineral-rich groundwaters

This article is based on a survey of tarns conducted mainly in the summers of 1983 to 1985, plus a survey made in the winter of 1985, in which streams were sampled on the wide variety of rock-types occurring on the fringes of the Lake District. Differences in composition of major ions and their concentrations in the surface waters of Cumbria reflect the complex geological structure of the region. At altitudes above 300 m, on Borrowdale Volcanics and Skiddaw Slates, surface waters are derived from atmospheric precipitation, with additional inputs of some ions - especially calcium and bicarbonate - from catchment rocks and soils. In some of the low-lying large lakes on the fringes of the central fells, water composition is also dominated by inputs from upper catchments; examples are Wastwater, Ullswater and Haweswater. However in other lakes there is evidence (Derwentwater and Bassenthwaite Lake) of inputs from saline groundwater.

Some statistical aspects of the long-term gill net monitoring programme for pike Esox lucius in Windermere (English Lake District)

For more than 55 years, data have been collected on the population of pike Esox lucius in Windermere, first by the Freshwater Biological Association (FBA) and, since 1989, by the Institute of Freshwater Ecology (IFE) of the NERC Centre for Ecology and Hydrology. The aim of this article is to explore some methodological and statistical issues associated with the precision of pike gill net catches and catch-per-unit-effort (CPUE) data, further to those examined by Bagenal (1972) and especially in the light of the current deployment within the Windermere long-term sampling programme. Specifically, consideration is given to the precision of catch estimates from gill netting, including the effects of sampling different locations, the effectiveness of sampling for distinguishing between years, and the effects of changing fishing effort.

The ecology of Bassenthwaite Lake (English Lake District)

Bassenthwaite Lake is, in many ways, different from the other major lakes in the English Lake District: it is the most northerly, the shallowest, has the largest catchment and the shortest mean retention time. There is also considerable temporal variation in lake level. This article summarises the limnological features of Bassenthwaite Lake, the catchment and physical characteristics before describing the water chemistry, phytoplankton, macrophytes, zooplankton, invertebrates, fish, mammal and invertebrate population. The authors then describe the ecological pressures faced by Bassenthwaite Lake such as nutrients, sediments and introduced species.

Financial Futures Markets and Their Impact on the Real Economy in Middle and Low Income Countries

This project analyses the influence of the futures market on middle and low income countries. In it, I attempt to show that investments made by large investment funds in this market, as well as by certain pension plans, bring major consequences whose effects are more evident in less developed countries. The cornerstones of the work are as follows; to attempt to see the existing relationship between the commodity futures market and its underlying assets; analysing products such as wheat, rice and corn in-depth, because these are the most basic foodstuffs at a global level; to determine how an increase in trading in these markets can affect the lives of people in the poorest countries; to analyse investor concern regarding the consequences that their investments may have. Throughout the project we will see how large speculators use production forecasting models to determine the shortage of a commodity in order to take a position in the futures market to profit from it. In addition we will see how an increase in trading in this market causes an increase in the price of the underlying asset in the spot market. As for investor concern, I can say it is negligible, but the idea of running pension plans or investment funds that follow some social criteria has been welcomed by those interviewed, which makes me think that different legislation is possible. This legislation will only come into existence if it is demanded by the people. A fact that now becomes complicated because without a minimum financial basis, they cannot even know how the large investment funds trade with hunger in the world. The day when most people understand how large speculators profit from famine will be the day to put pressure on governments to begin to put limits on speculation. This makes financial awareness necessary in order to achieve a curb in excessive speculation.

A study of the reproductive biology of dace in the middle Ob [introduction , summary and table captions only] [Translation from: Trudy tomsk. gos. Univ. 125, pp.77-91]

The Siberian Dace (Leuciscus leuciscus baicalensis (Dyb)is an important trade fish in Siberian waters. In the Ob basin more than 30,000 centners are produced annually. Catches of dace fluctuate significantly both between different rivers and between years in the Tomsk region. Defining the stocks of dace in the waters of the Tomsk region and explaining the fluctuations over time seems to be a very important and relevant question for the workers of the fishing industry. An answer, however, requires an accurate knowledge of the biology of dace; its reproductive, feeding and migration habits and the conditions of wintering etc. In the following we examine one of the above questions i.e. the biology of the reproduction of dace. The study was carried out in the Middle Ob in May 1951. This tranlations provides the introduction, summary and table captions only of the original article.

The phytoplankton of an enriched, soft-water lakel subject to intermittent hydraulic flushing (Grasmere, English Lake District)

This paper describes some characteristic features of the phytoplankton of Grasmere, one of the smaller of the principal lakes of the English Lake District, and attempts to relate these to distinctive physical and chemical properties of the lake. Quantitative data presented herein are derived from 5-m vertical column samples, collected with a flexible polyethylene hose close to the deepest point of Grasmere, generally at intervals of 14 days ( 7 days from 1972 to 1978, inclusive). The study concludes that although Grasmere has been subject to increased phosphorus-loading and has quickly developed many features associated with eutrophication, the composition of its plankton has retained the characteristics of a mesotrophic, soft-water lake: a vernal diatom maximum, generally dominated by Asterionella, is followed by summer growths of nanoplanktonic species, of various colonial Chlorophyceae, before a substantial return to Asterionella-dominance in the autumn.

Acid precipitation and its effects on aquatic systems in the English Lake District

There is no evidence of an increase in the acidity (lower pH or alkalinity) of water-bodies in the Lake District over the last 50 years. Brown trout occur in acid streams and upland tarns where pH is 4.5-5.2 throughout the year. Their occurrence in such waters in Britain and Ireland has been known for most of this century and there is no previous evidence of harmful effects on salmonid fisheries, though numbers of fish are naturally low. However, many benthic invertebrates that are common in hill-streams where pH is above 5.7 do not occur in more acid streams. This phenomenon occurs in the headwaters of several western rivers in Cumbria. It is not a recent response to "acid rain". Harmful effects of pH are undoubtedly more pronounced in waters that are poor in other dissolved ions. Low concentrations of sodium, potassium, calcium and chloride are especially important and may limit the distributions of some aquatic animals even where pH is above 5.7. The concentration of sulphate ions is usually relatively high but this is not important to the fauna; concentrations are at least two times higher in productive alkaline water-bodies than they are in unproductive acid waters.

'The highly nervous system of the English Lakes': aquatic ecosystem sensitivity to external changes, as demonstrated by diatoms.

The author reviews the stratigraphic diatom profile of Cumbrian lakes since the last glaciation. Knowledge of both present and previous interglacials suggests that a natural cycle of change is imposed on all lakes. The nature of inwashed material is dependant on climatic and natural soilcycles and this affects the water quality and sensitive aquatic biota. Anthropogenic effects are superimposed upon this with forest clearance and pollution. Whilst some Cumbrian diatom profiles extend over the entire post glacial, others cover only detailed sections relating to particular problems. Causes and effect of recent changes in lakes can be studied using indicator species but palaeocology contributes greatly to understanding of long term changes.

The role of specially designated wildlife sites in freshwater conservation - an English perspective

The value of specially designated sites in conserving biodiversity has been a hotly debated issue for many years. The debate has recently been given fresh impetus by the creation of Natural England, the new Government Agency responsible for the protection and enhancement of the natural environment in England, and the challenges facing the management of designated sites resulting from the increasingly tangible effects of climate change. In the freshwater environment, the role of designated sites is very much under the spotlight because of the implementation of the European 'Water Framework' Directive, which aspires to holistic, ecologically-based management of aquatic habitats.This paper explores the underlying premises of, and rationale for, special site designations for wildlife, and provides a frank account of the inevitable clash of management philosophies that designated sites create in the freshwater environment, drawing on experiences of managing designated freshwater sites in England over the past decade. A positive role is outlined for designated sites in freshwater conservation, which addresses these management conflicts in a way that not only meets Government obligations towards these sites but also paves the way for enlightened, progressive management of the wider freshwater resource. As part of this account, attempts are made to clarify the relationship between key biodiversity-related policy drivers in the freshwater environment, and to explain how the spectre of climate change can be addressed within designated site management. The importance of strategic freshwater science, collaboratively designed and funded, in maximising the value of the designated freshwater site network to the wider freshwater habitat resource, is stressed.

Major ions in 25 frequently sampled tarns in the English Lake District (1954-56, 1974-1976) [Dataset]

This dataset provides raw data of chemical analyses made during studies on seasonal variations of 25 frequently sampled tarns in Cumbria. Measurements of sodium, calcium, potassium, magnesium, pH, chloride ions, alkalinity, sulphite, strong acids and nitrate were taken between 1954 and 1956 and between 1974-1976.

Concentrations of major ions in 182 tarns in the English Lake District (1953-1978) [Dataset]

This dataset provides raw data of chemical analyses made during studies on seasonal variations of 182 tarns in the English Lake District, Cumbria. Measurements of sodium, calcium, potassium, magnesium, pH, chloride ions, alkalinity, sulphite, strong acids and nitrate were taken between 1953 and 1978.