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1.
古代江南地区圩田开发及其对生态环境的影响   总被引:5,自引:0,他引:5  
江南地区的圩田大致滥觞于三国之际,迅速发展于两宋,全盛于明清,是我国江南人民在长期治田治水实践中创造的农田开发的一种独特形式。文章以大量历史文献资料为基础,全面考察了江南地区圩田开发的历程与特点,研究了江南圩田兴盛的历史因素和自然条件,并简要分析了圩田的作用。在此基础上,具体探讨了圩田开发对生态环境所造成的影响,认为因过渡围垦破坏了江南地区原有的湖泊河流水文环境,造成“水不得停蓄,旱不得流注”的严重局面,这便给圩田大大增加了防患水灾的压力;历代地方政府在圩田管理方面也是各自为政,各地圩田缺乏相互间的协作,使因破圩而形成的局部水灾年年有之;大量构筑圩田,使湖泊面积大为缩小,影响其调节水量的功能,破坏了本地区的生态条件,致使灾害频频发生。此外,围湖特别是废湖以后,使众多的水生资源也遭到了严重破坏。  相似文献   
2.
Written sources and iconographic evidence suggest that honey and beehive products, used in culinary, medicinal, and technological functions since pre-Neolithic times, were likely known and used in Phoenician and Punic Sardinia. The role of these resources is nonetheless poorly understood because no direct evidence survives on a macroscopic level. Significant advances in the knowledge about beeswax and beehive products processing in the past have been offered in recent decades by organic residue analyses (ORA), an approach that enables the characterisation of surviving chemical compounds or suites of compounds that provide information relating to human activity in the past. The relatively recalcitrant nature of lipid compounds comprising beeswax means that this commodity is among the products that can be unambiguously identified through ORA. Here we present and discuss the results of analyses undertaken on 368 pottery sherds from Phoenician and Punic Sardinia (eighth to third century BCE). These analyses offer direct evidence for the presence of beehive products on the island, suggesting the use of honey for culinary purposes in pots, and possibly connecting one specific vessel category with beeswax decanting during beekeeping and honey production processes. Our results also now clearly illustrate the widespread use of beehive products in pre-Roman Sardinia.  相似文献   
3.
Abstract

From 1865 to about 1910 studies of the chemistry of the brain were afflicted by the hypothesis that cerebral lipid matter consisted of a giant molecule from which all the simpler lipids were derived as breakdown products. In successive periods the main proponents of this ‘protagon’ theory were Oscar Liebreich, Arthur Gamgee and William Cramer. The theory was disproved by the careful and detailed studies of JLW Thudichum whose work on the brain was described in many papers, government reports, and two outstanding monographs. The controversy involved rough moments, generated by both sides, but by 1910, a few years after his death, Thudichum was fully vindicated in his opposition to the protagon concept and his classification of brain lipids became the accepted standard for biochemistry as a whole.  相似文献   
4.
Following the last humid phase of the Late Holocene, human groups left the Saharan latitudes of northern Mali at around 2500 cal. years BC to settle further south. The Kobadi population was among the first Neolithic human groups to enter the Niger Inland Delta in central Mali. People adapted to their new environment by intensifying one of their former subsistence practices, namely fishing. The rich and diversified ichthyofauna exploited was dominated by large Nile perches and a variety of catfish taxa. It testifies to relatively stable hydrological conditions: a fluvial lake which was probably linked permanently to the main Niger River. Fish were caught with harpoons and probably also with diverse fishing devices such as nets, baskets and fences. Preparation processes prior to cooking cannot be determined, but fish were probably cooked on hot coals or stones, the left‐overs of the meals being discarded randomly at the site. Intense exploitation of the aquatic environment near Kobadi provided an abundant, secure and predictable source of protein. Besides fish and riparian mammals, reptiles such as turtles, monitors and crocodile were hunted. Domestic cattle provided milk and/or meat. These animals were either raised at the site or obtained by means of exchange with pastoral groups roaming the hinterlands. From the 2nd millennium BC, the focus on aquatic resources at Kobadi, mostly through the intensification of fish exploitation, may demonstrate the beginning of economic specialisation in the Niger Inland Delta. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
5.
The Archaeology of Aquatic Adaptations: Paradigms for a New Millennium   总被引:1,自引:0,他引:1  
Although aquatic resources are often seen as central to the development of post-Pleistocene cultural complexity, most models of human evolution have all but ignored the role of aquatic or maritime adaptations during the earlier stages of human history. When did aquatic resources, maritime adaptations, and seafaring first play a significant role in human evolution? I explore this fundamental question by (1) reviewing various theories on the subject; (2) discussing a variety of problems that prevent archaeologists from providing a clear answer; and (3) examining the archaeological record for evidence of early aquatic resource use or seafaring. I conclude that aquatic resources, wherever they were both abundant and relatively accessible, have probably always been used opportunistically by our ancestors. Evidence suggests, however, that aquatic and maritime adaptations (including seafaring) played a significantly greater role in the demographic and geographic expansion of anatomically modern humans after about 150,000 years ago. Another significant expansion occurred somewhat later in time, with the development of more sophisticated seafaring, fishing, and marine hunting technologies.  相似文献   
6.
Archaeological leather samples recovered from the ice field at the Schnidejoch Pass (altitude 2756 m amsl) in the western Swiss Alps were studied using optical, chemical molecular and isotopic (δ13C and δ15N of the bulk leather, and compound-specific δ13C analyses of the organic-solvent extracted fatty acids) methods to obtain insight into the origin of the leather and ancient tanning procedures. For comparison, leathers from modern native animals in alpine environment (red deer, goat, sheep, chamois, and calf/cow) were analyzed using the same approach. Optical and electron microscopically comparisons of Schnidejoch and modern leathers showed that the gross structure (pattern of collagen fibrils and intra-fibrils material) of archaeological leather had survived essentially intact for five millennia. The SEM studies of the hairs from the most important archaeological find, a Neolithic leather legging, show a wave structure of the hair cuticle, which is a diagnostic feature for goatskins. The variations of the bulk δ13C and δ15N values, and δ13C values of the main fatty acids are within the range expected for pre-industrial temperate C3 environment. The archaeological leather samples contain a mixture of indigenous (from the animal) and exogenous plant/animal lipids. An important amount of waxy n-alkanes, n-alkan-1-ols and phytosterols (β-sitosterol, sitostanol) in all samples, and abundant biomarker of conifers (nonacosan-10-ol) in the legging leathers clearly indicate that the Neolithic people were active in a subalpine coniferous forest, and that they used an aqueous extract of diverse plant material for tanning leather.  相似文献   
7.
黄浦江水上旅游系统规划和开发   总被引:12,自引:0,他引:12  
张璟 《人文地理》2006,21(3):44-47
文章分析了水上旅游相对于陆上景区旅游的特性,说明其规划中系统观念运用的重要性,列出了黄浦江水上旅游系统的构成要素。文章剖析了两组核心要素即码头、游船和航线,管理、服务和营销,分别指出其规划开发的要点。文章指出码头的规划要注意合理布局、集中管理,提高码头利用率与经营效能。新建造或引进船型中应注意其通透性、景观性、现代性、主题化、系列化等。航线设计上应注意水陆结合、突出主题、联合开发等。  相似文献   
8.
Lipids preserved within the walls of ancient pottery vessels are routinely analysed to reveal their original contents. The provenience of aquatic lipids in pottery is generally connected to vessel function (e.g., for cooking or storing fish, shellfish and aquatic mammals). However, ethnographic reports from early historic Alaska mention the use of aquatic oils for waterproofing low-fired pottery. Results of lipid residue studies on Alaskan pottery reflect an exclusive function of pottery to process aquatic resources. However, can one be sure these residues are the product of vessel function and not a remnant of the manufacturing process? The study presents the results of an experiment where the preservation of aquatic lipids during the firing process at different temperatures was measured. It was found that nearly all lipids were removed at firing temperatures of ≥ 400°C. Petrographic analysis of Alaskan pottery samples indicates that firing temperatures were generally > 550°C but < 800°C. The contribution of pre-firing manufacture-derived lipids to samples fired at these temperatures may be regarded as negligible. While the possible presence of aquatic lipids from post-firing surface treatments cannot be excluded, such treatments appear unnecessary for well-fired pottery.  相似文献   
9.
Initiatives aimed at protecting aquatic ecosystems often prove difficult to implement—particularly in water‐stressed, semi‐arid regions where the demand for water for human consumption is high. This article reports on an investigation of the factors that shaped the development and implementation of policies for aquatic ecosystem protection in the Oldman River Basin (ORB), a crucial watershed in semi‐arid southern Alberta. The analysis reveals critical cultural and historical considerations that confront those attempting to protect and restore aquatic ecosystems in the ORB and highlights specific factors that influence implementation of measures to protect it. In addition to the most basic consideration—demand for water exceeds supplies—eight specific factors that influenced aquatic ecosystem protection in this region are identified and evaluated. These include (1) clarity of actors’ roles/ jurisdictional responsibilities; (2) communication; (3) definition of key terms; (4) funding and organizational capacity; (5) leadership; (6) legal standing; (7) data and monitoring; and (8) public education. We argue that while these factors are important, critical cultural and historical considerations that influence water policy in the province also must be addressed in any efforts to protect aquatic ecosystems in southern Alberta.  相似文献   
10.
A new heterosporous fern species, Azolla boliviensis sp. nov., is described from latest Maastrichtian (latest Cretaceous) to Paleocene (earliest Palaeogene) terrestrial sediments of the Eslabón and Flora Formations, Subandean belt, Bolivia. The species is represented by dissociated but abundantly co-preserved megasporocarps, megaspores, microsporangia, massulae and microspores. The genus consistently characterizes warm-climate lacustrine settings. Fossil Azolla is first identified around the Early to mid-Cretaceous but the genus apparently underwent dramatic radiation during the Late Cretaceous. Abundant Azolla remains in Bolivia add to this portrait of rapid geographie dispersai and diversification near the close of the Cretaceous. The ranges of many Azolla species span the Cretaceous- Palaeogene boundary and the potential of Azolla to withstand altered environmental conditions, such as periodic frost damage, drought, and salinity change, and its ability to undergo rapid vegetative regeneration in association with nitrogen-fixing cyanobacterial symbionts, suggest that the survival of this group was favoured during the adverse conditions of the end-Cretaceous event.  相似文献   
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