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世界黄麻、红麻纤维与制品的生产和贸易
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作者 黄培坤 《中国麻作》 北大核心 1995年第2期40-42,共3页
100多年以来,世界黄麻生产久兴不衰,但近10多年以来,由于合成纤维和集装箱运输取代了部分麻袋;国际市场上稻米价格高,农民将部分麻田改种水稻;以及世界市场上黄麻供需形势的变化,价格不稳定,导致黄麻种植面积、纤维和制品... 100多年以来,世界黄麻生产久兴不衰,但近10多年以来,由于合成纤维和集装箱运输取代了部分麻袋;国际市场上稻米价格高,农民将部分麻田改种水稻;以及世界市场上黄麻供需形势的变化,价格不稳定,导致黄麻种植面积、纤维和制品的产量均有所下降。本文报道近10年来世界黄麻、红麻种植面积、纤维和制品的生产、进出口和价格等情况。 展开更多
关键词 黄麻纤维 纤维制品 合成纤维 海森布 红麻纤维
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Implications of mass elevation effect for the altitudinal patterns of global ecology 被引量:10
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作者 张百平 姚永慧 《Journal of Geographical Sciences》 SCIE CSCD 2016年第7期871-877,共7页
The varied altitudinal gradient of climate and vegetation is further complicated by mass elevation effect(MEE), especially in high and extensive mountain regions. However, this effect and its implications for mountain... The varied altitudinal gradient of climate and vegetation is further complicated by mass elevation effect(MEE), especially in high and extensive mountain regions. However, this effect and its implications for mountain altitudinal belts have not been well studied until recently. This paper provides an overview of the research carried out in the past 5 years. MEE is virtually the heating effect of mountain massifs and can be defined as the temperature difference on a given elevation between inside and outside of a mountain mass. It can be digitally modelled with three factors of intra-mountain base elevation(MBE), latitude and hygrometric continentality; MBE usually acts as the primary factor for the magnitude of MEE and, to a great extent, could represent MEE. MEE leads to higher treelines in the interior than in the outside of mountain masses. It makes montane forests to grow at 4800–4900 m and snowlines to develop at about 6000 m in the southern Tibetan Plateau and the central Andes, and large areas of forests to live above 3500 m in a lot of high mountains of the world. The altitudinal distribution of global treelines can be modelled with high precision when taking into account MEE and the result shows that MEE contributes the most to treeline distribution pattern. Without MEE, forests could only develop upmost to about 3500 m above sea level and the world ecological pattern would be much simpler. The quantification of MEE should be further improved with higher resolution data and its global implications are to be further revealed. 展开更多
关键词 mass elevation effect intra-mountain base elevation TREELINE altitudinal belt Tibetan Plateau
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