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Medium 9780253351982

Epilogue: Diving in the Cincinnatian Sea

Richard Arnold Davis Indiana University Press ePub

 

Many paleontologists, ourselves included, became fascinated with fossils and embarked on scientific careers long before we ever encountered living marine animals. For many of us, the greatest thrill has been our first encounters with living representatives of the animal groups we knew first only as grey, lifeless forms encased in rock. Both of us have been privileged to examine firsthand living relatives of animals of our favorite groups of fossils—crinoids for Meyer and nautiloid cephalopods for Davis. Our experiences have fueled a curiosity that affects practically anyone who contemplates the fossil richness of the Cincinnatian or other comparable fossiliferous strata. Many times, in the field, we stand on a Cincinnatian outcrop where fossils are abundant in almost every rock, and we wonder: what did the Cincinnatian sea actually look like? How did these creatures behave when alive? If we could travel back in time to dive into the Cincinnatian sea, what would we see?

In his book The Crucible of Creation, the paleontologist Simon Conway Morris (1998) takes the reader on a journey through time in an imaginary time machine that lands on the shores of the Cambrian sea in western Canada of 520 million years ago. The time machine then descends into the sea and enables time traveling scientists to view the varied and bizarre animals found as fossils in the famous Burgess Shale. Conway Morris recreated the environment of the Cambrian sea and the life within it from the evidence of the fossils and rocks, but he embellished the scenario with a measure of speculation and fantasy.

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Medium 9781845938116

7 The Effects of Plant-Soil Feedbacks on Invasive Plants: Mechanisms and Potential Management Options

Monaco, T.A., Editor CAB International PDF

7

The Effects of Plant–Soil

Feedbacks on Invasive Plants:

Mechanisms and Potential

Management Options

Valerie T. Eviner1 and Christine V. Hawkes2

1

2

Department of Plant Sciences, University of California, USA

Section of Integrative Biology, The University of Texas, USA

Introduction

There are countless examples of management projects that have attempted to decrease or eradicate invasive species at a site, only to have them rapidly recolonize within a few years. While this is often attributed to reinvasion through propagules remaining at the site, or high propagule pressure from the surrounding landscape (Leung et al., 2004;

Lockwood et al., 2005), this also may be due to invasive species changing site conditions to favor conspecifics over native species.

Many studies have documented that invasive plants can impact numerous soil properties and processes (Leffler and Ryel, Chapter 4, this volume; Ehrenfeld, 2010), and that invader impacts on soil can influence competitive dynamics between plant species, often favoring the invaders (Callaway and

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Medium 9781576336366

Solutions: GED Chemistry

Ace Academics Ace Academics ePub
Medium 9780253355058

8 The Geospatial Semantic Web, Pareto GIS, and the Humanities

David J Bodenhamer Indiana University Press ePub

TREVOR M. HARRIS, L. JESSE ROUSE, AND SUSAN BERGERON

The so-called spatial turn in the humanities represents a complexity of ideas and applications and the term is in dire need of unpacking. At the very base level the spatial turn represents an awareness of the significant role that space plays in human actions and events, and specifically the influence that space plays in humanities disciplines. Without question, the spatial turn has been heavily driven by the growing awareness and availability of Geographic Information Systems (GIS).1 There have long been exchanges between geography and the humanities that extend as far back as Carl Sauer’s inaugural work in cultural geography and his use of examples from history, archaeology, and cultural landscape studies.2 Historical geography has certainly been at the forefront of this symbiosis in seeking to explore geographies of the past through a blend of human geography and the historical method.3 It is not surprising then that the early usage of GIS in the humanities has been predominantly in historical GIS, which has drawn upon the primary strengths of GIS in the areas of mapping, gazetteers, and vector boundary delineation to support the geographies of major databases such as historical censuses and the production of atlases. Significantly there has been little demonstrated use of GIS in the humanities that draws upon the extensive spatial analytical sophistication of the technology. In the disparate, largely uncoordinated and application-driven foray of GIS into the humanities, mapping has been without question the dominant expression of the geospatial turn and in many ways the (re)discovery of the power of the map has become synonymous with the spatial turn.

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Medium 9781780644202

28: Can Small Still Be Beautiful? Moving Local Sweetpotato Seed Systems to Scale in Sub-Saharan Africa

Low, J. CABI PDF

28 

Can Small Still Be Beautiful? Moving

Local Sweetpotato Seed Systems to Scale in Sub-Saharan Africa

M. McEwan,1* C. Almekinders,2 P.E. Abidin,3 M. Andrade,4

E.E. Carey,5 R.W. Gibson,6 A. Naico,4 S. Namanda7 and S. Schulz8

1

International Potato Center Sub-Saharan Africa (CIP-SSA),

Nairobi, Kenya; 2­Wageningen University, Wageningen, The Netherlands;

3

CIP, Lilongwe, Malawi; 4CIP, Maputo, Mozambique; 5CIP, Kumasi,

Ghana; 6Natural Resources Institute, Chatham Maritime, UK; 7CIP,

Kampala, Uganda; 8CIP, Addis Ababa, Ethiopia

Abstract

In sub-Saharan Africa (SSA), a range of farmer-­based practices for the conservation and multiplication of sweetpotato planting material has evolved. In bimodal rainfall areas, sequential planting ensures that a ware crop is in the ground for most of the year, and vines are harvested from one crop to plant the next one. In unimodal areas with a long dry season, practices include the use of ‘volunteer’ planting material from sprouting roots which have been left in the ground from the previous crop. The predominant sources of planting material are from the farmer’s own field or from friends or neighbours. However, these practices result in limited amounts of planting material being available at the start of the rains and contribute to the build-up of pests and diseases contributing to suboptimal root crop production. Sweetpotato breeding efforts are leading to the development of new varieties that are preferred by farmers and consumers. However, without strong linkages to seed multiplication and dissemination efforts these varieties may not quickly benefit large numbers of smallholder farmers and consumers. Increasingly there are specialized vine multipliers who have been supported by

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Medium 9781576336373

Work and Energy: GED Physics

Ace Academics Ace Academics ePub
Medium 9781607321408

GYMNOSPERMS

Ronald C. Wittmann University Press of Colorado ePub

The gymnosperms are woody vascular plants that do not produce true flowers, but instead bear mega- and microsporangia on the open faces of sporophylls that are often grouped together in cones. In eastern Colorado these fall into two families, separated by the following key.

1a.   Fruit a gray, berry-like cone, the scales fused together and only detectable by their protruding tips; shrubs or small trees with decussately arranged, scale-like leaves or flat sharp needles. Cupressaceae, CYPRESS FAMILY

1b.   Fruit a woody cone with spirally arranged scales; small or large trees with needle leaves. Pinaceae, PINE FAMILY

This is a very ancient family, going back to the Jurassic, with relictual species and genera scattered over the world. Cupressus, the true cypress, has centers of diversity in California and around the Mediterranean. Juniperus is also essentially a Mediterranean genus, with a single outlier, J. communis, in the mountains of the Northern Hemisphere. Sabina is well represented by a number of species in the mountains and steppes of North America and Eurasia. The common names “cedar” and “juniper” are very loosely used for various genera of this family. In fact, the true cedars (Cedrus) belong to the pine family.

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Medium 9781603442909

Gas Hydrates in the Gulf of Mexico

Buster, Noreen A. Texas A&M University Press ePub

Deborah R. Hutchinson, Carolyn D. Ruppel, Harry H. Roberts, Robert S. Carney, and Michael A. Smith

Interest in the Gulf of Mexico has been greatly accelerated in the past decade, and there is much evidence that this interest will continue, which should result in the eventual solution of many of the present riddles of the Gulf of Mexico. When S. A. Lynch wrote these words half a century ago (Lynch 1954, p. 83), gas hydrates were not anticipated as one of the riddles of the Gulf of Mexico. The occurrence of gas hydrates in the Gulf was first predicted in 1979, when key indicators in seismic data suggested their presence (Shipley et al. 1979a). Samples of these elusive materials were not discovered in the Gulf until about 1983 when hydrate was recovered in cores and dredges in the Green Canyon area (Brooks et al. 1984; Kennicutt et al. 1985). Since these first discoveries in the Gulf, studies have expanded rapidly; now the Gulf is one of the best-studied natural laboratories for understanding seafloor gas hydrate mounds and marine gas hydrate occurrence within a leaky world-class petroleum system.

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Medium 9780253002358

15 Evolution in the Tasman Sea

Rudolf A. Raff Indiana University Press ePub

In the early 1980s, I started earnestly hunting for the right organism as an experimental system for delving into evo-devo. I thought the ideal animal would be one in which the evolution of early embryonic and larval development could be readily studied because embryos and larvae are crucial stages in development and are simple in cell numbers and types compared to adults. My first efforts were made using the familiar sea urchins of the Northern Hemisphere. I found that we could explore evo-devo at the gene level in sea urchins and published our first evo-devo paper in 1984. In it we showed that a major innovation in the expression of histone genes in sea urchin eggs had taken place with the origins of advanced sea urchins in the Mesozoic, while brontosaurs munched their way across the landscape. We could thus correlate a unique gene regulatory mechanism with a set of macroevolutionary events in sea urchin evolution. But the events were too distant in the past to help unravel ongoing developmental evolution. So I’d have to look farther afield.

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Medium 9780253000804

1: The Arctic Setting

Roland A. Gangloff Indiana University Press ePub

The Arctic Coastal Plain circa Seventy Million Years Ago

The Arctic coastal plain is crisscrossed by a host of meandering rivers that drain the northern slope of the rugged ancestral Brooks Range to the south. The rivers are pregnant with organic-rich sediment and rush headlong to the northern sea, being fed by melting snowfields and the common cloudbursts that sweep in from the Western Interior Seaway to the north and east. Large herds or aggregates of duck-billed dinosaurs move along river banks feeding on dense “gardens” of mud-loving horsetail rushes that have sprung forth from their subterranean rhizomes into the reawakening sunlight.1 Monodominant patches of drought-resistant ferns are interspersed with clumps of herbaceous angiosperms and grasses on small ridges and levee slopes.2 Stacks and tangles of lichen and moss-encrusted logs and branches form along the edges of sloughs and oxbow lakes. Large logs of deciduous conifers, such as Parataxodium from forests deep in the interior, have mixed with smaller ones that had spent their lives closer to where they now lie.

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Medium 9789383828593

Ch_3_F

K.V.S.G. Murali Krishna Laxmi Publications PDF

Effects of Air Pollutants

31

3

EFFECTS OF AIR

POLLUTANTS

A normal human being breathes about 25,000 times a day at a rate of about 1�2 litres of air per breath i.e., about 25,000 to 50,000 litres/day i.e., about 30 to 60 kg of air per day. Thus the quantity of air consumed by an average man is about 25 times more by weight and 20,000 times more by volume than the quantity of water consumed. A person can survive for five weeks without food and five days without water but only five minutes without air. In addition, the air we breath interacts with the most sensitive organs of human body. Hence the air we breath must be of a very good quality. Unfortunately man is not equipped with household or portable air cleaning devices unlike water filters etc. and thus demands a clean ambient air for his health and well-being which is more than a luxury today.

Air that surrounds a man has a direct impact on his health and property. The health of a man is determined by the interplay and integration of the internal environment of man himself and the external environment that surrounds him. A disease is only due to a disturbance in the delicate balance between man and his environment. Now a days it is not only stacks or chimneys alone where soot is detected as a cause of cancer but carcinogens are found else where also in the environment where very potent cancer causing agents such as benzopyrene and many other polyaromatic hydrocarbons are present in significant concentrations in air. Of course, man is the primary source of air pollutants. He breathes fresh air and emits polluted air containing pathogens and other aeroallergens, CO, CO2 and odours. A study by the World Health Organisation shows that 75�90% of all cancers are caused due to environmental factors and are related to agents present in air, water, work environment and personal choice of lifestyle including tobacco smoking and chewing, alcohol consumption and sexual promiscuity. The effects of air pollutants on atmosphere, animals including man, materials and vegetation are thoroughly discussed in this chapter.

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Medium 9780253356512

5. From Corrosion to Collapse: The Destruction of Native Communities

Nicholas A. Robins Indiana University Press ePub

“Neither Livestock nor Lands nor Houses”: A Horrific Homecoming1

The mita, mercury, and silicosis did not just kill and maim individuals, they also did the same to countless indigenous communities throughout the altiplano and valleys as their effects reverberated throughout the region. As a key element in the colonial exploitative equation, the mita exacerbated both the ongoing abuses against Indians by their overlords as well as divisions among the elite as they competed for Indian labor. Further complicating the situation were the myriad physical and mental effects of quicksilver and silicosis previously described. In addition, while Potosí was for many years the most important mining town in the Andes, silver production and mercury pollution occurred throughout the region on both small and large scales. As a result, both free and forced laborers, mine owners, colonial officials, clergymen, artisans, and anyone or anything else in these areas that breathed were at a high risk of being poisoned. Governors, priests, officials, and commoners did not stay in one place but often moved as they sought better lives or purchased new jurisdictions, positions, and parishes. The result was that the human effects of mercury and silver production were by no means limited to Huancavelica, Potosí, and other mining centers, and those who were poisoned became carriers who imported their afflictions to towns and cities that did not produce silver or mercury. Such was the profoundly exploitative nature of colonial society, however, that mercury only exacerbated entrenched practices and abuses. Examining what natives had to contend with in their villages rounds out the picture of what awaited them if they returned home from the mita, and underscores the broader, regional effects of the amalgamation economy.

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Medium 9780874217919

8 On the Same Page

Bruce L. Smith Utah State University Press ePub

I eagerly delivered reports—annual progress reports, habitat inventory summaries, status reports of big game species—to the Tribal Fish and Game Committee and Joint Business Council. Certain council members would thumb the pages and glance curiously at me as if to say, “I am not impressed by how much time you spend at a typewriter.”

Most of these documents were skimmed at best. I knew that. But I regarded chronicling our findings an essential contribution for succeeding biologists, tribal leaders, and the Shoshone and Arapaho people. This permanent record was the benchmark by which future efforts to restore WRIR’s natural treasures would be gauged.

I liked that my position provided access to tribal decision-makers. It is not that it conferred a sense of self-importance; rather it made my work feel relevant. Being at the Joint Business Council’s beck and call and able to schedule a time slot to present some pressing matter of my work to this governing body was gratifying and often hastened decision making.

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Medium 9781780648378

1: Cherry Production

Quero-Garcia, J. CABI PDF

1 

Cherry Production

Géza Bujdosó1* and Károly Hrotkó2

National Agricultural Research and Innovation Centre Fruitculture Research

Institute, Budapest, Hungary; 2Szent István University, Faculty of Horticultural

Science, Budapest, Hungary

1

1.1 Introduction

Sweet (Prunus avium L.) and sour (syn. tart,

Prunus cerasus L.) cherry ripen first among stone fruits, followed by apricot, peach and plum. Because sweet cherry is first on the fresh market, it is in high demand in the late spring and early summer. Sweet cherry cultivars with a red fruit colour dominate the market, while cultivars of yellow, white or blush colour are in less demand. Sour cherries have smaller fruit size and are less firm than sweet cherries. The vast majority of sour cherries are processed; however, sour cherries with higher sugar content are becoming more common on the fresh fruit market in recent decades.

Sweet cherry cultivars span a longer maturity period than sour cherries. In temperate zones of the northern hemisphere, sweet cherry cultivars mature from the end of April (in southern growing regions) to

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Medium 9780253008831

27 Taphonomy of a Subadult Teratophoneus curriei (Tyrannosauridae) from the Upper Campanian Kaiparowits Formation of Utah

Alan L Titus Indiana University Press ePub

Jelle P. Wiersma and Mark A. Loewen

The Upper Campanian Kaiparowits Formation of Utah has recently produced an associated subadult skeleton of the tyrannosaurid dinosaur Teratophoneus curriei. The approximately 65% complete skeleton includes most of the skull; representative elements from the entire axial column; a complete pelvis; and the right femur, tibia, and fibula. The quarry also has produced leaves, logs, abundant aquatic mollusks, a partial hatchling hadrosaurid, elements from a larger subadult hadrosaurid, a crocodilian, a bird, and a lizard, all preserved in a silty claystone, resulting in a multitaxic monodominant bonebed assemblage. We interpret the sedimentology of the quarry as the result of deposition in shallow standing water in a floodplain depression following an overbank flood. All of the elements lack any indication of surface weathering, insect modification, scavenging, or predation. The skull, vertebrae, and pelvis exhibit breakage penecontemporaneous with burial. These elements exhibit greenstick fractures perpendicular to the bedding plane. Recovered elements exhibit exceptional preservation with an absence subaerial weathering or predation marks. We suggest a taphonomic history of death and burial of the animal in standing water followed by an overbank flood event. This resulted in burial and disarticulation of the skeleton in fine-grained sediments, followed by partial trampling of the skull and skeleton in shallow standing water or waterlogged sediment. This interpretation contrasts with interpretations of most other vertebrate localities in fine-grained sediments within the Kaiparowits Formation, which exhibit multiple examples of predation and insect modification.

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