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Within the next five years, Chinese trade with Africa is predicted to reach $100 billion per year. Much of this springs from China's growing expansion into Africa's oil markets. It is argued that Chinese oil diplomacy in Africa has two main goals: in the short-term to secure oil supplies to help feed growing domestic demand back in China; and in the long-term, to position China as a global player in the international oil market. Yet at the same time, this oil safari is being accompanied by an explicit stance that emphasizes state sovereignty and 'non-interference' in domestic affairs and is wholly disinterested in transparency or human rights. Consequently, Beijing has increasingly been accused of turning a blind eye to autocracy and corruption. China is also threatening to undercut efforts by the African Union and its western partners to make government and business more accountable. While China is providing investment where little was previously forthcoming, concerns about Beijing's engagement with Africa's oil industries need to be resolved, not least by African leaders themselves.  相似文献   
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Economic globalisation has led to a huge increase in demand for food, goods and services by expanding urban middle class populations. These demands cause environmental changes that in turn feed back upon the urban environment and human population. While the global changes are well researched, the cumulative significance of local environmental changes is less well known. Yet, the local changes may have greater impact on the decisions which individuals make that affect soil erosion and land degradation. People respond to family circumstances and to local economic opportunities in ways that most suit the needs of their families and households. Several demonstration projects that were not adopted offer lessons in understanding how people make their land‐use decisions. An understanding of people's past experiences, present needs and views of the future helps those seeking to improve environmental management to promote policies and actions that are likely to succeed by being acceptable to those involved.  相似文献   
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To help improve the well‐being of the local people, a joint Vietnamese‐UK team set out to establish a way of estimating soil and nutrient losses under different land management scenarios, using field data extrapolated through remote sensing and GIS, to obtain catchment‐wide estimates of the impact of land cover change. Immigration from remote provinces to the Dong Phu District of Binh Phuóc Province, about 120 km north of Ho Chi Minh City, has led to disruption of soil surface stability on easily eroded clayey sandstones, creating rapid nutrient depletion that affects crop yields and siltation in the channel of the Rach Rat river downstream. The poor farmers of the areas see crop yields drop dramatically after two or three years of cultivation due to the fertility decline. Soil loss varies dramatically between wet season and dry season and with ground cover. Erosion bridge measurements showed a mean loss of 85.2 t ha?1 y?1 under cassava saplings with cashew nuts, 43.3 t ha?1 y?1 on uncultivated land and 41.7 t ha?1 y?1 under mature cassava. The rates of erosion were higher than those reported in many other parts of Vietnam, reflecting the high erodibility of the friable sandy soils on the steep side‐slopes of the Rach Rat catchment. However, although the actual measurements provide better soil loss data than estimates based on the parameters of soil loss equations, a large number of measurement sites is needed to provide adequate coverage of the crop and slope combinations in this dissected terrain for good prediction using GIS and remote sensing.  相似文献   
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Over Bonavista Peninsula, in northeast Newfoundland, ice-flow directional indicators reveal two styles of glaciation. The inner part was glaciated by ice of the Newfoundland Ice Cap, flowing northeast but drawn down strongly into deep channels in Bonavista and Trinity bays and basally deflected northward by a line of hills bisecting the peninsula. The outer peninsula was almost completely glaciated by the contiguous, dynamically independent Bonavista Ice Divide, with coastward flow. Near the northeast extremity a low plateau, mantled with blockfield and bearing no obvious traces of glaciation, is flanked by a subdued end moraine. The moraine is argued to represent the local entire Wisconsinan glaciation limit. Evidence from soil development on the moraine and elevations of emerged post-glacial shore features, as well as from comparison with glacial history in nearby areas, is used to argue a late Wisconsinan (pre-12,000–13,000 BP) age for the later part of glaciation. Evidence of widespread till deposition far offshore can be harmonized with evidence of incomplete Wisconsinan glaciation onshore by postulating persistent discharge of inland ice through the deep, compound fiord basins that flank Bonavista and other east Newfoundland peninsulas Les indicateurs du passage des glaciers dans la péninsule de Bonavista située au nord-est de Terre-Neuve signalent l'oeuvre de deux styles de glaciation. La Calotte Glaciaire de Terre-Neuve recouvrait tout I'intérieur de la Péninsule; se déplaçantvers le nord-est, elle était forcee de suivre par les baies profondes de Bonavista et de Trinité, et détournée à sa base en direction du nord par les collines qui franchissent la péninsule du nordau sud. Pour sa part, I'extérieur de la péninsule gisait entièrement sous le Diviseur Glaciaire Bonavista, qui tout en étant contigu obéissait à une dynamique indépendante et s'écoulait en direction des côtes. A I'extrémité nord-est de la pénin sule, sous un manteau de blocs rocheux, se trouve un bas plateau qui ne porte aucune trace de glaciation et qui est bordé d'une fine moraine terminale. Selon l'argument proposé, cette moraine représente en cet endroit la limite extrême des glaciers du Wisconsin. Des indices provenant de la formation des sols sur cette moraine et des hauteurs atteintes par la mer postglaciaire, de même qu'une comparaison avec l'histoire des glaciations dans les zones environnantes, permettent d'avancer que la fin de la dernière glaciation remonte à celle du Wisconsin (avant 12 000 à 13 000 ans AP). Des liens existent entre les dépots très répandus de till, loin au large des côtes, et les indices d'une glaciation incomplète durant le Wisconsin sur ces côtes, dans la mesure où l'on postule qu'il y eut une décharge soutenue de glace en provenance de l'intérieur, le long des fiords profonds et complexes qui bordent la peninsule de Bonavista de même que d'autres péninsules de Terre-Neuve.  相似文献   
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Caravan parks are an important component of the tourist industry. They serve as the dormitory and the focal point for the immediate environs at places of interest. This paper investigates the characteristics and the occupancy of parks which were inundaled by water during the April/May floods of 1988 in New South Wales. It looks at the number of people at risk, and the appropriateness of caravan parks occupying land liable to flood. This form of accommodation offers people a great flexibility in their holidaying patterns but when long-term or permanent caravans are concentrated in parks on floodprone land they pose a number of problems. In addition to human elements such as personal property damage and social disruption, substantial disaster relief payments from public funds are required. It appears quite inappropriate 10 allow floodprone caravan parks to have sites occupied on a long-term basis.  相似文献   
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