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1.
旅游业是一个对外界环境较敏感的行业,易受到突发事件的影响。暴恐事件属于危机事件的一种形式,由于其突发性、不确定性,对旅游业的破坏力大、持续时间长,因此应积极采取应对措施来降低暴恐事件给旅游业带来的冲击和损失。搜集昆明近三十年来的入境旅游统计数据,建立昆明入境旅游客流量和旅游外汇收入本底趋势线,结合月指数和本底线距平方法,高分辨率地分析了"3. 01"暴恐事件的影响。研究发现:2014年"3. 01"暴恐事件发生之后,昆明入境旅游客流量和入境旅游外汇收入受到了严重的冲击,2014—2016年三年共损失客流量86. 7万人次,损失率高达19. 3%;入境旅游收入损失共计43688. 6万美元,损失率高达26. 2%,该影响持续至今并有逐年扩大趋势。 相似文献
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在人工合成的化学农药造成严重环境污染的今天,随着人们健康和环保意识的不断提高,从除虫菊植株中提取出来的天然除虫菊酯以其高效广谱性和环境友好性再次引起人们的关注。通过对比天然除虫菊酯和目前使用广泛的人工合成的拟除虫菊酯,从化学结构、作用范围、杀虫效力、抗性、生态毒性、稳定性和成本等方面进行分析,发现拟除虫菊酯在应用过程中逐渐暴露出高抗性、毒性和环境蓄积性等弊端,而天然除虫菊酯却是具有环境友好性的生物农药。最后,从政策、市场需求和技术等层面对天然除虫菊酯的发展方向提出建议。 相似文献
4.
燃煤电厂海水烟气脱硫工艺原理初探 总被引:12,自引:1,他引:11
海水烟气脱硫工艺是利用天然的纯海水(燃煤电厂可直接利用电厂的冷却循环水)作为烟气中SO2的吸收剂,无需其它任何添加剂,也不产生任何废弃物,具有技术成熟、工艺简单、系统运行可靠、脱硫效率高(理论脱硫效率可达98%)和投资运行费用低等特点,目前在一些国家和地区已得到日益广泛的应用。本文是在部分模拟试验的基础上,对海水烟气脱硫工艺进行了简单的阐述。 相似文献
5.
Removal of thiobencarb in aqueous solution by zero valent iron 总被引:2,自引:2,他引:0
A cost-effective method with zero valent iron (ZVI) powder was developed for the purification of thiobencarb (TB)-contaminated water. The removal treatment was performed in the batch system. A sample solution of 10 ml containing 10 microg ml(-1) of TB could be almost completely treated by 100mg of ZVI at 25 degrees C for 12h of treatment time. Since the formation of chloride ion in the aqueous solution during the treatment of TB was observed, the removal of TB with ZVI may contain two processes: reduction (degradation) and adsorption. Because the present treatment for TB is simple, easy handling and cheap, the developed technology with ZVI can contribute to the treatment of agricultural wastewaters. 相似文献
6.
This study combined laboratory based microcosm systems as well as field experiments to evaluate the mobility of atrazine on a Ultisol under humid tropical conditions in Brazil. Results from sorption experiments fit to the Freundlich isotherm model [K(f) 0.99 mg kg(-1)/(mg l(-1))(1/n)], and indicate a low sorption capacity for atrazine in this soil and consequently large potential for movement by leaching and runoff. Microcosm systems using (14)C-atrazine to trace the fate of the applied herbicide, showed that 0.33% of the atrazine was volatilized, 0.25% mineralized and 6.89% was recorded in the leachate. After 60 d in the microcosms, 75% of the (14)C remained in the upper 5 cm soil layer indicating atrazine or its metabolites remained close to the soil surface. In field experiments, after 60 d, only 5% of the atrazine applied was recovered in the upper soil layers. In the field experiments atrazine was detected at a depth of 50 cm indicating leaching. Simulating tropical rain in field experiments resulted in 2.1% loss of atrazine in runoff of which 0.5% was adsorbed onto transported soil particles and 1.6% was in solution. Atrazine runoff was greatest two days after herbicide application and decreased 10 fold after 15 d. The use of atrazine on Ultisols, in the humid tropics, constitutes a threat to water quality, causing surface water and ground water pollution. 相似文献
7.
落实科学发展观,构建和谐社会是当前我国社会主义建设的目标与发展原则。和谐社会的内涵包括众多内容,即民主法治、公平正义、诚信友爱、充满活力、安定有序、人与自然和谐相处等,从宏观上来看,就是促进经济、社会与生态的协调与可持续发展。生态学是研究生物及环境间相互关系的科学,随着生态学的不断发展及其与经济学、社会学等学科的交融,逐渐成为认知自然、社会与经济关系,促进其协同发展的理论基础,在构建和谐社会过程中将起着重要的、不可代替的作用。 相似文献
8.
Improvements on Flood Alleviation in Germany: Lessons Learned from the Elbe Flood in August 2002 总被引:1,自引:0,他引:1
The increase in damage due to natural disasters is directly related to the number of people who live and work in hazardous
areas and continuously accumulate assets. Therefore, land use planning authorities have to manage effectively the establishment
and development of settlements in flood-prone areas in order to avoid the further increase of vulnerable assets. Germany faced
major destruction during the flood in August 2002 in the Elbe and Danube catchments, and many changes have been suggested
in the existing German water and planning regulations. This article presents some findings of a “Lessons Learned” study that
was carried out in the aftermath of the flood and discusses the following topics: 1) the establishment of comprehensive hazard
maps and flood protection concepts, 2) the harmonization of regulations of flood protection at the federal level, 3) the communication
of the flood hazard and awareness strategies, and 4) how damage potential can be minimized through measures of area precaution
such as resettlement and risk-adapted land use. Although attempts towards a coordinated and harmonized creation of flood hazard
maps and concepts have been made, there is still no uniform strategy at all planning levels and for all states (Lae
nder) of the Federal Republic of Germany. The development and communication of possible mitigation strategies for “unthinkable
extreme events” beyond the common safety level of a 100-year flood are needed. In order to establish a sustainable and integrated
flood risk management, interdisciplinary and catchment-based approaches are needed. 相似文献
9.
The methodology of materials accounting is presented and applied to developing nutrient balance (nitrogen and phosphorus)
in a river basin. The method is based on the balance principle: inputs and outputs of each nitrogen and phosphorus related
sub-systems were balanced. The application of the methodology strategies was illustrated by means of a case study of the Krka
river, Slovenia. Different pathways of emission to surface waters were taken into account: WWTP discharges, direct discharges,
erosion/runoff and baseflow. Total annual emission into the river Krka was estimated to be 362 tonnes N/year and 73.3 tonnes
P/year. The main sources of nitrogen are diffuse sources, emitted via baseflow (52%). Other important sources are effluents
from WWTP, which account for 36% of total emissions. Other sources like erosion and direct discharges to surface water (animal
manure, industry, households) are of lower magnitude. Erosion is main source of phosphorus emission (55% of total emission),
WWTP effluents account for 37% of total emission, while other sources are less important. Besides reduction of point sources
by means of wastewater collection and implementation of nutrient removal technology, managing agricultural nitrogen and phosphorus
to protect water quality should become a major challenge in the Krka river basin. 相似文献
10.