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971.
以贵州肇兴侗寨为案例地,运用列斐伏尔的空间生产理论,采用田野调查与深度访谈结合的方法,从物理空间、社会空间、意义空间3个维度审视多元权力主体的“物质-关系-情感”联结以及与旅游发展的自洽性。结果表明:1)物理空间在权力主体的更迭下得以重新规划,有助于劳动力的回流。村寨的原真性在规制的约束下得以维护,但建构的景观符号是对民族村寨的错位表达。2)对于社会空间中的冲突,当地居民采取退让不退出的策略与管理者达成空间错时使用与管理默契。威权人物寨老成为消解分歧、推动社会关系巩固与凝聚的代表。对游客及外来经营户的让渡与周全,体现了当地居民开放包容的待客之道与处事哲学。3)意义空间通过当地居民对节事、文化的情感注入,对文化惯习的传承、对乡约的承继、对怀旧物的回忆与想象得以再生产。对于处在发展上升期的民族村寨而言,多元权力主体会基于利益的共同性与社会关系的粘连性考虑,做出符合当地旅游发展与自身容纳限度的调适与让步,来适应旅游发展带来的空间变化。 相似文献
972.
从“水-能源-粮食”3个维度对粤港澳大湾区的生态系统服务进行评价,利用珞珈一号夜光数据修正生态阻力面,运用最小累积阻力模型构建并优化湾区的生态安全格局。结果表明:1)粤港澳大湾区生态源地总面积为9 626.1 km2,主要分布在研究区东部和西部的山地、丘陵地区,对应位于江门市、惠州市中部和肇庆市;2)生态廊道共计38条,总长度为2 023.09 km,其中最短为11.76 km,最长为304.99 km,集中于植被覆盖较好的山地丘陵地区,中部无廊道分布;3)生态源地辐射区面积为28 929.5 km2,达到湾区总面积的51.88%,若要实现60%的覆盖率,则需要至少新增生态源地辐射面积4 524.856 km2;4)为了更好地优化粤港澳大湾区生态安全格局,提出在惠州市北部和南部新增两处生态源地辐射区,并构建以“一带、一轴、四组团”为核心的生态安全格局优化模式。 相似文献
973.
Fan Jie Li Sisi Sun Zhongrui Guo Rui Zhou Kan Chen Dong Wu Jianxiong 《地理学报(英文版)》2022,32(7):1203-1224
Journal of Geographical Sciences - The coordinated development of urban and rural territorial systems has long been a scientific issue of concern in geography and socioeconomic development in... 相似文献
974.
Zhangyu Dong Zongming Wang Dianwei Liu Kaishan Song Lin Li Mingming Jia Zhi Ding 《Journal of the Indian Society of Remote Sensing》2014,42(3):569-576
Increasing interest in wetlands for environmental management requires an understanding of the location, spatial extent, and configuration of the resource. The National Wetlands Inventory is the most commonly used data source for this information. However, its accuracy is limited in some contexts, such as agricultural and forested wetlands. An large number of studies have mapped wetlands worldwide from the perspective of land use and land cover change. However, information on the actual wetland planting areas annually is limited, which greatly impacts ongoing research. In this case study of the West Songnen Plain, we developed a simple algorithm for the quick mapping of wetlands by utilizing their unique physical features, such as annual display of phenological land-cover change of exposed soils, shallow flooding water, and plants from multi-temporal Landsat images. Temporal variations of the Normalized Difference Vegetation Index (NDVI) and Land Surface Water Index (LSWI) derived from Landsat images in 2010 for wetlands at different growth stages were analyzed. Results show that during the ante-tillering phase, the NDVI value (above zero) is lower than the LSWI value of paddies because of flooding of shallow water; during the reproductive and ripening phases, the NDVI value is higher than the LSWI value (above zero); and during the post-harvest wetland planting phase, the NDVI value is still higher than the LSWI value, but the LSWI value is negative. Wetland areas can be detected using one or two images in the optimum time window. The algorithm based on the difference of NDVI and LSWI values derived from Landsat images was used to extract the actual wetland planting area. Validated alongside statistical data, the algorithm showed high accuracy. Therefore, this algorithm highlights the unique features of wetlands and can help in mapping the actual wetland area annually on a regional scale. Results further indicate that the new method has a classification accuracy of 92 %. In comparison, two traditional methods based on Landsat-7/ETM registered accuracy rates of only 83 % and 87 % respectively. 相似文献
975.
976.
Use of the L2C signal for inversions of GPS radio occultation data in the neutral atmosphere 总被引:1,自引:0,他引:1
S. V. Sokolovskiy W. S. Schreiner Z. Zeng D. C. Hunt Y.-H. Kuo T. K. Meehan T. W. Stecheson A. J. Mannucci C. O. Ao 《GPS Solutions》2014,18(3):405-416
Results from processing FORMOSAT-3/COSMIC radio occultations (RO) with the new GPS L2C signal acquired both in phase locked loop (PLL) and open loop (OL) modes are presented. Analysis of L2P, L2C, and L1CA signals acquired in PLL mode shows that in the presence of strong ionospheric scintillation not only L2P tracking, but also L1CA tracking often fails, while L2C tracking is most stable. The use of L2C improves current RO processing in the neutral atmosphere mainly by increasing the number of processed occultations (due to significant reduction in the number of L2 tracking failures) and marginally by a reduction in noise in statistics. The latter is due to the combination of reduced L2C noise (compared to L2P) and increased L1CA noise in those occultations where L2P would have failed. This result suggests application of OL tracking for L1CA and L2C signals throughout an entire occultation to optimally acquire RO data. Two methods of concurrent processing of L1CA and L2C RO signals are considered. Based on testing of individual occultations, these methods allow: (1) reduction in uncertainty of bending angles retrieved by wave optics in the lower troposphere and (2) reduction in small-scale residual errors of the ionospheric correction in the stratosphere. 相似文献
977.
Kuznetsov S. N. Bogomolov A. V. Denisov Yu. I. Kordylewski Z. Kudela K. Kurt V. G. Lisin D. V. Myagkova I. N. Podorol'skii A. N. Podosenova T. B. Svertilov S. I. Sylwester J. Stepanov A. I. Yushkov B. Yu. 《Solar System Research》2003,37(2):121-127
Based on X-ray, gamma-ray, and charged-particle measurements with several instruments onboard the Coronas-F satellite and on ACE and GOES experimental data presented on the Internet, we investigate the parameters of the solar flare of November 4, 2001, and the energetic-particle fluxes produced by it in circumterrestrial space. The increase in relativistic-electron fluxes for about 1.5 days points to a moving source (shock front). The structure of the energetic-particles fluxes in the second half of November 5, 2001, can be explained by the passage of the coronal mass ejection that was ejected on November 1, 2001, and that interacted with the shock wave from the flare of November 4, 2001. 相似文献
978.
E. P. Mazets S. V. Golenetskii V. N. Ilyinskii V. N. Panov R. L. Aptekar Yu. A. Guryan M. P. Proskura I. A. Sokolov Z. Ya. Sokolova T. V. Kharitonova A. V. Dyatchkov N. G. Khavenson 《Astrophysics and Space Science》1981,80(1):3-83
Data are presented on the temporal structure, fluxes, energy spectra and coordinates of the sources of gamma-ray bursts detected in the KONUS experiment on Venera 11 and Venera 12 space probes in the period September 1978 to May 1979. The statistical distributions of gamma bursts in duration, intensity, and peak power, as well as the distribution of the burst sources over the celestial sphere presented are based on the updated KONUS information obtained until February 1980. 相似文献
979.
本文给出利用中国、意大利、南非射电望远镜对一个近赤道源样本在5GHz频率上进行MK2VLBI普测中10颗弱源的相关流量和其中部分源用HartRAO望远镜观测的总流量值,作为进一步的MK3或VLBA记录系统的VLBI观测依据. 相似文献
980.