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41.
Recently, rice fields dated between 5000 and 2500 BC were found at the Tianluoshan sit in east China. The early rice fields dated between 5000 and 4500 BC are the oldest rice fields known. The discovery has provided data of recovering reclamation, cultivation, and the ecological system of rice fields in the Neolithic age. People opened up marshes of dense reeds with fire and wooden or bone spades, in order to create rice fields. In the rice fields, there was not only rice, but a lot of weeds as well. The excavations proved that little or even no weeding or irrigation was adopted. However, tilling soil by wooden and bone tools was evidenced. The average yields are estimated to have been about 830 kg for the early period and 950 kg per hectare for the later period. The cultivation system was low-level. Although the Tianluoshan people cultivated rice, they still obtained a great deal of food by gathering and hunting.  相似文献   
42.
Abstract: Our goal in this paper is to identify how recent escalations in immigration enforcement and changes in migration practices affect the ability of the state to continue to serve two of its key “productive” functions: protecting capital accumulation within industry and ensuring the state's own political legitimacy in the eyes of the public. We draw on our ethnographic research on Latino migrant dairy farm workers in Wisconsin to examine the ways in which a group of migrant workers experiences the process of being enforced as “illegal” bodies. We find that migrant dairy workers’ palpable sense of “deportability” articulates with the specific structure of dairy work in ways that make the economically and politically “ideal” migrant: compliant at work and invisible otherwise.  相似文献   
43.
Results of analyses of the photoperiod response gene (PPD-H1) and simple sequence repeats (SSRs) in modern landraces of cultivated barley were used as evidence for the mechanism of agricultural spread in Neolithic Europe. In particular, we explored the usefulness of considering adaptive genes as indicators of past selective pressures acting on crops, during their spread through Europe. In some areas, such as the Alpine region, Britain and Scandinavia, we have evidence to suggest that the adaptation of crops to certain climatic conditions may have contributed to the timing of agricultural spread. At the northern fringes of Europe, and in higher altitude locations in central Europe, the introduction of more suitably adapted cereals may have facilitated successful agriculture to trigger agricultural expansion. This research opens up the possibility of investigating other genetic adaptations to climate, which would permit a fuller evaluation of the relative contributions of climate/crop and forager/farmer interactions in the process of agricultural spread.  相似文献   
44.
由于"左"的错误和自然灾害,中国在1959~1961年出现了三年经济困难,当时最突出的问题是农业生产遭遇严重挫折,粮食极度短缺。为加快农业生产的恢复,20世纪60年代初,国家制定了"吃饭第一"的方针,要求各行各业支援农业。利用财政手段增加对农业的投入是贯彻这一方针的重要举措。国家财政支援农业的措施主要有两方面:一是减少提取农业剩余;二是直接增加对农业和农村的财政投入。  相似文献   
45.
在三年困难时期(1959—1961),由于政策上"左"的失误以及严重自然灾害的破坏,我国农业生产遭遇严重挫折,粮食产量连年大幅减少,给人民生活带来严重影响。为了促进农业生产的恢复,国家提出各行各业支援农业。其中,工业对农业的支援是其中一个重要组成部分。工业支援农业的内容主要有:压缩工业规模,增加生产农机、农具、化肥等。通过工业支援农业,农业生产得到一定程度的恢复。  相似文献   
46.
This article concerns the cross-interaction problem among multi-foundations on a linearly viscoelastic medium at very small shear strains. In the analysis, the foundations are discretized into a number of sub square-elements. The dynamic response within each sub-element is described by the Green’s function, which is obtained by the Fourier-Bessel transform and the precise integration method. Incorporating the displacement boundary condition and the force equilibrium of the foundations, it obtains the dynamic impedance and compliance functions of the foundations. Extensive results for two rigid circular foundations placed at different separations are presented. Parametric studies are carried out on the dynamic interaction among adjacent foundations. Illustrative results for several closely spaced foundations are also illustrated.  相似文献   
47.
An American geographer and noted international authority on water management problems in Russia and Central Asia presents an account of an expedition, in late 2005 (under the sponsorship of the National Geographic Society) to Kazakhstan and Uzbekistan, focused on the Aral Sea. The steadily drying inland sea, with a surface area of 67,500 km2 in 1960, had split into two parts and shrunk to 17,380 km2 in 2006. The paper provides an up-to-date overview of the crisis and presents an optimistic scenario of the sea's future, noting development of economic activities (particularly fisheries) in its surrounding settlements. Journal of Economic Literature, Classification Numbers: O13, Q15, Q25. 6 figures, 1 table, 55 references.  相似文献   
48.
Abstract

One of the basic areas of interaction between water as natural resource and human societies as agents of cultural transformation is the technology of irrigation. In Africa at least 66 per cent of the available water is used for purposes of irrigation. For more than 4 000 years irrigation has secured food supplies for humans on a continent that is noted for its relative shortage of sufficient natural water supplies.

There is a remarkable hidden power of water in the history of southern Africa. This is particularly the case when we consider the development of early irrigation technologies of Iron Age farmers. The small irrigation furrow of the subsistence farmer was just as important to an insular community of Bantu-speaking people in pre-colonial times, as is the sophisticated irrigation technology in present-day South Africa. Currently there is a paucity of information about pre-colonial indigenous irrigation technology. This can be ascribed to a number of factors of which the invasion of modern Western traditions in the nineteenth century is perhaps the most important. A number of other factors for the apparent blind-spot is also presented in this study.

In southern Africa there are traces of indigenous pre-colonial irrigation works at sites such as Nyanga in Zimbabwe; the Limpopo River Valley; Mpumalanga; and South Africa's eastern Highveld. Reference is also made in this article to specific strategies of irrigation used by Iron Age communities, prior to the advent of a colonial presence. Finally, attention is also drawn to pre-colonial land tenure and state formation against the backdrop of Wittfogel's theories on hydraulic society.  相似文献   
49.
In the now burgeoning scholarship on memory, there is a discernible shift from considering the politics of dominant public memory towards sites of counter-memories where vernacular forms of memory activism take place. This paper contributes to this by focusing its attention on plans to preserve Green Ridge in Kampar, Malaysia, a tract of forested hill that was the location of a fierce battle fought between the Japanese and Allied forces in the Asia-Pacific theatre of the Second World War. Specifically, it details the rescaling strategies of one particular individual to enhance the reach and relevance of the site for Malaysians writ large, primarily aimed at lobbying for Green Ridge to be officially marked as local and national heritage. This paper then interrogates issues that have hindered this process with the potential to ultimately thwart the preservation of the site for posterity. In doing so, the paper exemplifies memory activism as ‘work’, where local actors–through the mobilisation of scale politics–represent proactive agents in effecting change in public memory from below. Second, it highlights the fragmented nature of vernacular remembering and how this can impede memory work as much as champion memory formally obscured.  相似文献   
50.
Abstract: Much attention has been given in recent years to the rise of alternative food networks However, the very concept of “alternative” has come under increasing scrutiny, as theorists grapple with what is meant by alternative and whether the concept adequately captures the key components of such a diverse range of networks and communities. Drawing on poststructuralist political economy, I propose the concept of autonomous food spaces as one possible lens for approaches food‐provisioning activities that situate food within the broader context of non‐capitalist communities seeking to build relationships of mutual aid and non‐market exchanges. I use the examples of a radical collective kitchen, Food Not Bombs, and a community‐supported agriculture operation, Vegetables Unplugged, to explore the potential for autonomous food spaces as part of a broader “politics of possibilities” beyond capitalism.  相似文献   
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