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1.
Plaggen agriculture was the dominant land use system in the Pleistocene cover sand area of Northwest Europe before the introduction of chemical fertilisers. In today's landscape Fimic horizons and driftsand deposits are characteristic survivors of plaggen agriculture. The age and accumulation rate of these phenomena cannot be satisfactorily determined by conventional methods like pollen analysis and radiocarbon dating. The results of optical dating applied to a Fimic horizon of a plaggen soil near Weert (Netherlands) are compared with those from conventional methods.  相似文献   

2.
Ammonia is the crucial intermediate for the production of nitrogen fertilisers. BASF, today still one of the largest chemical companies in the world, was the first company to develop a process for the synthesis of ammonia from its compounds hydrogen and nitrogen: the well‐known Haber–Bosch process. Other processes were developed as well in the 1910s and ’20s but these technologies have often been classified as ‘imitations’, neglecting the crucial role they played in the take‐off of the fertiliser industry in the late 1920s and neglecting engineering contractors, companies that specialised in the design and construction of plants for the process industries. Engineering contractors diffused ammonia synthesis across the world and enabled the take‐off of the fertiliser industry. This paper attempts to show the role engineering contractors can play in the chemical industry and attempts to give a more balanced account of the history of ammonia synthesis by focusing on the fertiliser industry instead of BASF.  相似文献   

3.
Abstract

Traditionally, the study of man has been based on the study of his tools and artefacts, ideas and religion. Such an approach, tbough useful, is often inadequate, for it can fail to take into account items essential to man' survival which consequently play a major role in his history. Such an item is salt. The establisbment of early settlements, the rise and fall of populations, wars, large demographic shifts and the development of agriculture have in the past been intimately related to the absence or presence of salt. Power to control a population's salt supply was power over life and death. Much of our present civilization and habits are based on the ready availability of salt. Yet little attention has been paid to its importance in our lives, and little preparation has been made for a time when it may not be so easily accessible.  相似文献   

4.
Abstract

The interdisciplinary system described, for the transport of energy over long distances, has been under active investigation on a pilot plant stage for some years. Heat from a high temperature gas cooled nuclear reactor is proposed as an energy source to convert methane and steam, an endothermic chemical reaction, into carbon oxides and hydrogen – the EVA proces. The resulting gases can be pumped through pipes over long distance and, at the point of energy requirement, be converted back as an exothermic reaction – the ADAM process. Both reactions have been tested at Jülich with success and could be commercially Introduced at the end of the present century. Additional advantages are described for this closed circuit chemical heat pipe system.  相似文献   

5.
The aim of this work was to detect imprints on soil properties from former Islamic land use (9th to 11th century) using a multi-method, soil-chemical approach. Four soil profiles (with buried horizons) found in the vicinities of former Islamic settlements in Sicily were analysed for phosphorus (total, organic and inorganic), nitrogen (total, NO3 and NH4+), carbon compounds (δ13C, lipids, polycyclic aromatic hydrocarbons (PAH) and functional groups), physical and chemical C-fractions and the state of soil weathering. Two soil profiles contained ceramic sherds from the Islamic period. Inorganic nitrogen forms, phosphorous and the PAH content indicated strong impacts from traditional agriculture and/or burning. Radiocarbon dating of soil organic carbon (SOC) fractions from buried horizons showed that distinct changes must have occurred during the Islamic epoch. The isotopic composition of SOC indicated that land use was probably different in earlier times. C4 plant cultivation was expected but surprisingly lipid analyses did not confirm this. A high amount of aliphates and low C/N ratio indicated a good, long-term SOC stabilisation under the native conditions combined with Islamic land use. The irrigation of the soils probably increased the production of weakly-crystalline Fe forms that helped to stabilise SOC.  相似文献   

6.
Abstract

The Hospital of St Mary Magdalen, Partney has seen the first major excavation of a minor rural hospital. Existing by c 1115, it was amongst the earliest hospitals founded in Britain after the Norman Conquest and is one of a class of about 60 sites that were run as cells of larger religious foundations. Excavations uncovered the hospital chapel and its burial ground, as well as timber buildings. Monks/priests and lay people, possibly from the monastic estate, may have been interred in separate locations with different burial rites. Of particular note was a burial in a locked coffin or chest. Partney had ceased to function as a hospital by 1318, when it formed an administrative cell of Bardney Abbey. It was abandoned and robbed in the mid-15th century when the area was given over to agriculture.  相似文献   

7.
Abstract

An extensive survey followed by OSL (optically stimulated luminescence) dating of loess accumulation in agricultural terraces at six Byzantine and Early Islamic sites in the Negev Highlands revealed clear stratigraphic and chronological sequences. Traditionally dated to the 1st–7th centuries a.d., results from the present study demonstrate that the construction and use of largescale agricultural systems took place in the 4th–11th centuries a.d. This new chronology provides the framework for a more precise interpretation of the circumstances of construction and demise of largescale agriculture in the Negev Highlands. The agricultural fields were exploited continuously, yet ancient farmers had to confront the environmental hazards of occasional intensive floods, successive years of drought, and a constant process of loess accumulation and erosion. The constant maintenance and repair of fields necessitated an investment of labor. However, it seems that the expansion of ancient agriculture was part of the natural growth and development of Byzantine settlements in the Negev, and not the outcome of planned government enterprise. The agricultural systems were abandoned in the course of the 11th century a.d. and sporadically reused by pastoral nomads.  相似文献   

8.
ABSTRACT

The agricultural systems of the Hawaiian archipelago were some of the most intensive in the Pacific and this scale of intensity is well illustrated by the large agricultural landscapes of leeward Hawai‘i Island. Previous research in the area has centred on understanding the relationship between agriculture, political process, and large-scale environmental conditions. Much of this research has been oriented at the regional level, privileging discussion of elite management and oversight, with only limited investigation exploring farmer-centric adaptation at local scales. In this paper, we assess the integration of local and regional processes in Hawaiian agriculture using recent paired archaeological and ecological data from the Ka‘ū Field System as a case study. We demonstrate the presence of both general patterns previously identified in the archipelago and particular adaptations to the local environment of Kahuku ahupua‘a. In particular, we highlight targeted infrastructural developments that allowed for cultivation of what would otherwise be a difficult cultivation medium within the confines of a larger, likely regionally organised, field system constrained by general soil biogeochemical thresholds. We argue that such investigations provide an increased understanding on how these large-scale agricultural landscapes were formed by integration at multiple social and spatial scales.  相似文献   

9.
Abstract

Though the history of republicanism has been a popular topic of research since the mid-twentieth century, there are still various issues and areas that have remained neglected—not least the exchange of republican ideas from one cultural context to another, particularly across national boundaries. The purpose of this special issue is to offer some exploration of this neglected area, and this essay serves as an introduction to it. The essay offers an overview of the literature on republicanism that has been produced since the mid-twentieth century, it demonstrates the different ways in which republican exchange can be conceived and considers how the essays that follow contribute to our understanding of this issue, and finally it proposes a new way of thinking about republicanism.  相似文献   

10.
ABSTRACT

Canada’s dairy farmers have spent the last 40 years fighting to preserve their supply management system despite increases in the desire to liberalize trade through the expansion of regional free trade agreements and the targeting of agriculture in recent rounds of the General Agreement on Tariffs and Trade (GATT). How has Canada’s supply management system resisted trade liberalization thus far? Moreover, what strategies have Canadian dairy farmers used to lobby the government to preserve this system? The answer to these questions lay within the intersection of culture and economics. Canadian dairy farmers have been successful in framing Canadian dairy as a distinctly Canadian cultural commodity, and therefore framing supply management as the economic tool needed to defend this cultural commodity. In exploring this topic, this article will touch on Canada’s history of preserving cultural institutions, as well as the historical importance of Canada’s supply management system.  相似文献   

11.
This article presents a model of a developing economy with three sectors — industry, agriculture and energy. Industry and energy are assumed to be demand‐constrained, but agriculture supply‐constrained. The model highlights: (a) structural transformation, through labour transfer from agriculture to industry; (b) inflation, driven by the interaction of demand and the supply constraint in agriculture; and (c) the link between energy use and labour productivity. Employing a Kaldor‐Verdoorn productivity rule in industry augmented with energy intensity — energy per unit of labour — as an argument, we emphasize that labour productivity growth is driven by energy intensity rather than energy productivity growth. As a consequence, emissions reduction without North–South technology transfer and financial assistance costs growth.  相似文献   

12.
《Textile history》2013,44(1):28-56
Abstract

The economic causes of European emigration to the United States in the nineteenth century enjoy an established historiography, which considers many aspects of the pre-industrial economy from agriculture to the collapse of traditional industries. This paper examines the link between pre-industrial home textile manufacture and emigration from the German south-west. It draws on data from communities and households in the state of Württemberg, and finds that pre-industrial textile production was not a major determinant of migration patterns in the nineteenth century; instead, the localised rise and fall of textile work was influenced by the availability of emigration pathways, an inversion of results seen elsewhere.  相似文献   

13.
Abstract

This paper discusses how soil biological information can help to improve understanding of, and possibly inform decisions about, preservation of organic archaeological remains by reburial. A brief summary of the properties of the soil biological community is followed by an outline of results from recent biological investigations following the recovery of archaeologically relevant materials that had been buried for thirty-three years in one of the experimental earthworks in England UK. Examples from the soil biology and fertility literature are discussed to illustrate the effects of fluctuations in soil wetness and aeration, and of nitrogen availability on decomposition. Finally, the impact of soil handling and physical disruption on biological processes in soil are discussed, as they influence whether soil functions can be restored at a reburial site once the archaeological resources have been ‘protected’ beneath.  相似文献   

14.
This paper assesses the prospects for Soviet gas exports to Western Europe, analyzing both supply (domestic) factors, such as gas production, consumption, and transportation, and demand (foreign) factors such as gas demand and market share. This is done using a network allocation model of the Soviet gas pipeline network (for 1985, 1990, and 1995) and a country-by-country analysis of the gas market in Western Europe. In general, the outlook for increased gas exports to Western Europe, at least to the turn of the century, is rather bleak. This is mainly due to a relatively slower rate of growth of gas demand in Western Europe than projected earlier, coupled with overcontracting of gas supplies, because the USSR has enormous gas reserves, ample production, and no major pipeline bottlenecks restricting export volumes. Its huge pipeline construction program allows both domestic consumption and exports to be comfortably accommodated  相似文献   

15.
Abstract

The British farming community is rapidly diminishing due to its ageing workforce, the rise of second-home ownership, and the costs involved in running a farming business in the twenty-first century. The private nature of this community, often coupled with a deeply held mistrust of non-farmers has made it difficult to ascertain farmers’ own feelings on their current situation, and how things have reached such a position. This article explores how some of the major twentieth-century events for agriculture have affected a single Yorkshire farming community by tracing the deteriorating relationship between farmers and the government, through changing legislation and reactions to crises, from a point where farmers were held to be vital to Britain’s survival through to one where the agricultural community finds it plausible that their own government would actively try to destroy their livelihoods.  相似文献   

16.
ABSTRACT

For over a century the church that the Greek monks of Dayr Mar Saba are known to have possessed inside the walls of Jerusalem in the twelfth century has usually been associated with a chapel surviving inside the Disy family house opposite the police barracks south of the Citadel, while the Zāwiyyat al-Shaykh Ya?qūb (Ya?qūbiyya), on the east side of Christ Church, has been identified as having originally been built in the twelfth century, possibly by Monophysites, as a church dedicated to St James the Persian, or the ‘Cut-up’ (Intercisus). New documentary research, however, now makes it appear more likely that Mujīr al-Dīn was correct in attributing the building of the Ya?qūbiyya to the Greeks and that it was also the church referred to by pilgrims in the twelfth century as that of St Sabas. This means that the identity of the church in Dār Disy, if indeed it was a church, remains to be determined.  相似文献   

17.
Abstract

Excavations on the multi-period settlement at Old Scatness, Shetland have uncovered a number of Iron Age structures with compacted, floor-like layers. Thin section analysis was undertaken in order to investigate and compare the characteristics of these layers. The investigation also draws on earlier analyses of the Iron Age agricultural soil around the settlement and the midden deposits that accumulated within the settlement, to create a 'joined-up' analysis which considers the way material from the settlement was used and then recycled as fertiliser for the fields. Peat was collected from the nearby uplands and was used for fuel and possibly also for flooring. It is suggested that organic-rich floors from the structures were periodically removed and the material was spread onto the fields as fertilisers. More organic-rich material may have been used selectively for fertiliser, while the less organic peat ash was allowed to accumulate in middens. Several of the structures may have functioned as byres, which suggests a prehistoric plaggen system.  相似文献   

18.
Abstract

Based on microfossil and soil data, we discuss a different methodological approach to agricultural and domestic archaeological studies, taking two Formative sites in the north-west Argentinian high valleys (province of Catamarca) as case studies, independently of traditional datasets and historical analogies. As a result of our investigations we not only recognised the vegetal species cultivated in ancient fields (dated to c. AD 800) but also distinguished some of the agricultural practices, such as crop rotation and alternation, use of animal fertilisers and irrigation resources, as well as the abandonment of the site. From this perspective, corral episodes could also be distinguished. In residential enclosures, we obtained results concerning activity areas, the definition of floors and the identification of reoccupations.  相似文献   

19.
20.
Abstract

The global phenomenon of the birth of agriculture remains an enigma and challenges the role of food storage. Much has been written about their invention. A general explanation is needed for its progression in various parts of the world, which is both sociologically based and founded on the archaeological data. This task led Alain Testart to claim that it was by developing their existing skill sets (foraging, pottery, food storage and small-scale agriculture) that nomadic hunter-gatherers, burdened by an increasingly diverse set of tools and equipment, became sedentary. This sedentarism in turn allowed them to specialise in those activities, which had (literally) weighed them down: notably, breeding the first plant cultivars and, often, storing food.  相似文献   

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