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51.
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???????????2002??2003???2004??2005??????????????????????????????????????????????????????????????????Ч?????????????????????????????????????????????????????????????????????????????????????????????????? 相似文献
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YuLong Duan FaSi Wu DongPeng He RuiHong Xu HuYuan Feng Tuo Chen GuangXiu Liu WanFu Wang 《寒旱区科学》2021,13(6):522-532
In this study, a systematic survey of cultural airborne fungi was carried out in the occurrence environments of wall paintings that are preserved in the Tiantishan Grottoes and the Western Xia Museum, China. A bio-aerosol sampler was used for sampling in four seasons in 2016. Culture-dependent and -independent methods were taken to acquire airborne fungal concentration and purified strains; by the extraction of genomic DNA, amplification of fungal ITS rRNA gene region, sequencing, and phylogenetic analysis, thereafter the fungal community composition and distribution characteristics of different study sites were clarified. We disclosure the main environmental factors which may be responsible for dynamic changes of airborne fungi at the sampling sites. The concentration of cultural airborne fungi was in a range from 13 to 1,576 CFU/m3, no significant difference between the two sites at the Tiantishan Grottoes, with obvious characteristics of seasonal variation, in winter and spring were higher than in summer and autumn. Also, there was a significant difference in fungal concentration between the inside and outside of the Western Xia Museum, the outside of the museum was far more than the inside of the museum in the four seasons, particularly in the winter. Eight fungal genera were detected, including Cladosporium, Penicillium, Alternaria, and Filobasidium as the dominant groups. The airborne fungal community structures of the Tiantishan Grottoes show a distinct characteristic of seasonal variation and spatial distribution. Relative humidity, temperature and seasonal rainfall influence airborne fungal distribution. Some of the isolated strains have the potential to cause biodeterioration of ancient wall paintings. This study provides supporting information for the pre-warning conservation of cultural relics that are preserved at local sites and inside museums. 相似文献
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The key indicators of transboundary water apportionment based on international laws and cases 总被引:1,自引:0,他引:1
Transboundary water, more competitive utilization and uncertain availability under the globalization trend, the issue of its apportionment which directly impacts national benefits of each riparian state is becoming one of the important topics in the world. Water is scarce in China, the most important upstream state in Asia, and this task has to be thought over in the coming future. Based on "International Freshwater Treaties Database" (1820-2007) by Oregon State University, and publications and reports on transboundary water utilization and management since 1999, 28 indicators of water apportionment adopted in 49 international treaties and cases in 1864-2002 are divided into 6 types, the spatial and temporal characteristics of the adopted indicators are analyzed in order to find the key indicator(s) of transboundary water apportionment. The major results include: the major adopted indicators, have significant differences among 5 regions/continents, the indicators at rank first and second place in the developed region (North America and Europe) according to the adopted times are "keeping minimum water flow" and "mean annual runoff", but in the developing region (Asia, Africa and South America), the ranking order of the above two indicators is reversed; the major adopted indicators in the watersheds with insufficient water are "mean annual runoff" and "keeping minimum water flow", the ones in the watersheds with sufficient water are "keeping minimum water flow" and "maximum water intake"; the international treaties signed from the first phase to the fourth phase, the developing process shows a progress of "fewer-increasing a lot-decreasing rapidly-equation basically", the regional distribution of the treaties shifts mainly from the developed region to the developing one, especially to Asia and Africa; the major adopted indicators shifts from "keeping minimum water flow" and "mean annual runoff" in 1864-1945, to "keeping minimum water flow" and "maximum water intake" in 1946-1971, then to "hydraulic facility operation" and "mean annual runoff" in 1972-1991, and finally to "keeping minimum water flow" and "mean annual runoff" in 1992-2002, the process shows similar a loop. Finally, the key indicator on transboundary water apportionment can be determined as "keeping minimum water flow". 相似文献
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特克斯河流域近236a降水变化及其趋势预测 总被引:3,自引:0,他引:3
根据2006年采自特克斯河流域6个采样点的树轮样本研制的树轮宽度年表与气象资料,通过相关普查发现,特克斯河流域树轮标准化年表与上年7月至当年6月的降水存在显著的正相关,最高单相关系数为0.727.用库尔克尔也灭,小白代的树轮宽度标准化年表序列,可较好地重建该地区最近236 a的降水序列,方差解释量达54%,并通过交叉检验表明重建结果是稳定可靠的.近236 a,特克斯河流域上年7月至当年6月降水经历了8个偏湿阶段和8个偏干阶段,同时重建降水序列具有10.3 a、7.5 a、6.0 a、3.0 a、2.1 a的变化准周期,并在1790年,1911年,1929年,1974年发生过降水突变.采用毛毛虫-奇异谱分析法(Caterpillar-ssa)对该地区未来20 a的降水的自然变化进行预测.结果表明,21世纪的最初几年降水量将延续20世纪90年代以来增加的趋势,之后出现下降,并在2013~2016年前后最低值出现. 相似文献
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建设智慧景区,对于景区实现精细化、低碳化、移动化的管理方向,并最终实现"智慧旅游"的发展战略具有重要意义。目前对于智慧景区的探讨多集中于技术、管理和服务层面,尚无文献从游客视角对智慧景区评价指标体系进行研究。本文运用因子分析方法,构建了基于游客的智慧景区评价指标体系,提出应该从景区智能管理系统、信息服务智能系统、智慧游览系统、智慧预报系统、旅游电子支付、景区综合智能系统、景区安全救助智能系统、景区智能交通系统和景区资源保护智能系统9个方面进行智慧景区的建设。在此基础上,运用模糊综合评价方法,以南京夫子庙秦淮风光带为例,进行了智慧景区的实证评价。最后,对夫子庙秦淮风光带智慧景区建设的优势、不足以及对策进行了分析。 相似文献
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