WATER TABLE AND REDOX CONDITIONS IN DEEP TROPICAL PEAT

Changes in redox potential(RP)are the resultof the combined effects between many chemical,physical and biological processes in the soil.Soil oxi-dation and reduction depend on soil respiration,diffu-sion of oxygen and carbon dioxide in soil and onchanges …     

大小兴安岭高位泥炭孢粉纪录及泥炭发育和演替过程研究

根据３个高位泥炭剖面孢粉分析和＾１４Ｃ测年数据，以及植物残体、微量元素与营养元素等分析相互印证，揭示大小安岭分别５０００ａ Ｂ．Ｐ．和２７００ａ Ｂ．Ｐ．以来孢粉组合特征和植物群与气候演变过程。分析表明大小兴安岭高位泥炭形成了低、中和高位发育阶段的演变，大兴安岭高位泥形成晚于小兴安岭。１３００ａ Ｂ．Ｐ．大小兴安岭普遍发育高位泥炭。该区图强和汤北（９４－Ａ）高位泥炭剖面分别是大小兴安岭高位泥炭标准     

RADIOCARBON DATING OF A PEAT DEPOSIT IN THE CUCAMONGA FAULT ZONE,CALIFORNIA*

A sequence of peat beds was deposited in a small sag pond along the Cucamonga fault zone during late Holocene. The stratigraphic section of this deposit is described; several beds have been radiocarbon dated. Comparison of radiometric and stratigraphic chronologies allows reconstruction of the geomorphic history of the sag pond, which extends back 3000 years, and establishes evidence that the fault has been active within the very recent geologic past.     

COLONIAL EXPERIENCE AND THE DEVELOPMENT OF TROPICAL GEOGRAPHY IN FRANCE

This article broadly positions the successful establishment of the field of French tropical geography in the immediate postwar period against developments stemming from a longer history of French colonial engagement in Africa, Asia and South America, and clarifies the seemingly late timing of, and paradoxes involved in, the creation of a body of French scientific knowledge about the tropics. Colonial scientific research did not develop in France until the end of the nineteenth century. However, the colonial geography appearing at this time did not rely on fieldwork but, rather, catered to the demands of the business class for overseas expansion and to public curiosity. Even while the medical geography of tropical areas and knowledge of tropical soils and ecology progressed greatly between 1900 and 1940, there were still only a few French geographers working in the tropics. With the advent of the Second World War, when “big science” appeared in France and its colonial empire, the number of French geographers involved in tropical research grew rapidly. The field of tropical geography built up by Pierre Gourou was a synthesis of approaches developed in South America, Africa and Indochina. Although it soon came under strong criticism for its pessimistic view of prospects for industrialisation and urbanisation in the tropics, it seduced French geographers because it matched the contemporary interest in zonality and relied on a genre de vie analysis of, typically, rural areas. Thus, the postwar blossoming of tropical geography shaped by Gourou was more a response to various internal dynamics within French geography than an exercise in imperialism. Its demise was not due to the eclipse of French colonialism but, rather, its inability to deal with the modernisation of tropical societies.     

西双版纳勐养保护区热带林保护GIS研究

西双版纳是生物多样性的荟萃地, 利用 Ｇ Ｉ Ｓ进行保护研究十分重要。研究共分３ 个部分： （１） Ｇ Ｉ Ｓ的建立。（２） Ｇ Ｉ Ｓ的应用。其中包括物种资源保护、环境监测和可持续发展规划。（３） 提高 Ｇ Ｉ Ｓ实用性的探讨。结果认为： 保障数据源质量、数据标准化、控制数据处理和增强数学模型的灵敏度是提高 Ｇ Ｉ Ｓ实用性的重要途径。