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In recent times major changes have occurred in extensive areas of Lapland inhabited by the reindeer-herding Lapps of northern Fennoscandia (Norway, Sweden, Finland, and the Kola Peninsula in the Soviet Union). Their customary way of life, delicately attuned to the ecological conditions of the arctic and subarctic areas, is buffetet between the environment-adapted life of the timeless tundra, forests, and swapms and the modern industrialized economy of northern Europe.The Lapps in the northern part of the reindeer-herding region have maintained some of the old nomadic ways and are closely tied to the habits of the reindeer, providing a simple but excellent example of the way that man can use nature without destroying it. The continued practice of reindeer ecology may serve as the catalyst that will keep the occupation of reindeer husbandry alive and make possible an orderly fusion with modern trends. 相似文献
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For the period September 1978 to December 1982 we have identified 55 solar flare particle events for which our instruments on board the ISEE-3 (ICE) spacecraft detected electrons above 10 MeV. Combining our data with those from the ULEWAT spectrometer (MPI Garching and University of Maryland) electron spectra in the range from 0.1 to 100 MeV were obtained. The observed spectral shapes can be divided into two classes. The spectra of the one class can be fit by a single power law in rigidity over the entire observed range. The spectra of the other class deviate from a power law, instead exhibiting a steepening at low rigidities and a flattening at high rigidities. Events with power-law spectra are associated with impulsive (<1 hr duration) soft X-ray emission, whereas events with hardening spectra are associated with long-duration (<1 hr) soft X-ray emission. The characteristics of long-duration events are consistent with diffusive shock acceleration taking place high in the corona. Electron spectra of short-duration flares are well reproduced by the distribution functions derived from a model assuming simultaneous second-order Fermi acceleration and Coulomb losses operating in closed flare loops. 相似文献