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11.
12.
西安地区旅游景点水体卫生细菌学调查及保护对策 总被引:1,自引:0,他引:1
以粪大肠菌和异养细菌总数做指标,对西安地区旅游景点水体的卫生细菌学状况进行了调查。结果表明,西安市区内旅游景点的人工湖、天然湖等大都受到不同程度的污染,而离市区较远、海拔较高的旅游景点则污染较轻。 相似文献
13.
R. G. W. Smith George Mulamoottil 《Journal of the American Water Resources Association》1979,15(6):1524-1537
ABSTRACT: In Ontario no major studies have been attempted in the area of water-oriented recreation to guide planned development. To fill this gap a comprehensive investigation was undertaken on a group of lakes in the District of Muskoka, one of the premier tourist regions of the province. This paper presents the results of this study which focusses on the lake environment, recreational activities, attitudes, and perceptions of the cottagers. 相似文献
14.
The effects of trampling on the coral communities of the outer reef flat and reef crest were investigated at Heron Island at the southern end of the Great Barrier Reef. Eighteen months of trampling at various intensities increased the percentage cover of unoccupied substrate and the cover of mobile rubble. The morphology of the coral was the most important feature relating to trampling resistance. Branching corals were reduced on the outer reef flat, and most broken branches were recorded in the initial phases of the experiment. The reef crest was much more resistant.A short-term trampling experiment showed that trampling detached a greater mass and larger fragments of coral on the outer reef flat than on the reef crest. Further trampling reduced the sizes of the detached fragments on the outer reef flat. A drift experiment indicated that greatest movement of fragments occurred on the reef crest and here the largest fragments moved greater distances.We concluded that all habitats would be changed by reef walking and that by one measure the outer reef flat was 16 times more vulnerable than the reef crest. The routes taken by reef walkers need to be chosen in relation to the trampling resistance of the habitat. 相似文献
15.
应用环境噪声主观反应调查和现场实地测试调查的统计结果,根据心理学确定阈值的原则,提出我国风景旅游区两种区域类型的环境噪声标准的建议,并对标准的可行性和代表性进行了分析和讨论. 相似文献
16.
利用地下盐穴进行各种工业废物的埋藏处理目前在国外已得到很好的应用。文章针对油田废钻井液的填埋处理技术,详述了建设盐穴所需要选择的地质条件:必须具有良好的封闭性;造穴方式主要通过水溶洗盐形成地下溶洞;埋藏废物需要通过一系列的特定工艺才能完成;废钻井液埋藏处理后需要进行监测以防止产生污染事故。一般来说,由于地下盐穴埋深大、盐穴封闭性好,具有较高的安全性。利用盐穴进行废钻井液的埋藏具有费用低、容量大、占地少、安全性高等优点。 相似文献
17.
Francesca Beolchini Viviana Fonti Sevda Özdemiroğlu Ata Akcil Antonio Dell’Anno 《Chemistry and Ecology》2017,33(2):103-113
Acidophilic S-oxidising bacteria isolated from sulphur-rich deep caves (Frasassi, Italy), characterised by relatively low temperature, were tested for their ability to mobilise (semi-)metals from contaminated sediments. Sediment samples from two commercial Italian seaports were used to set up bioleaching experiments. The effect of different growth substrates was also investigated. Our experiments revealed that S-oxidising bacteria isolated from Frasassi caves have a high potential to remove As from contaminated marine sediments, as never reported before. Although As solubilisation efficiency was quite low (i.e. about 30%), only a small amount of As was associated with non-residual fractions of the sediment. On the contrary, the solubilisation efficiencies of Zn and Ni (20% and 10%, respectively) were lower than those previously obtained by the use of other acidophilic bacteria and mainly influenced by the experimental conditions rather than by the presence of the S-oxidising bacteria. Results presented here open new perspectives in bioleaching applications for the remediation of contaminated sediments. Indeed, microbial strains adapted to relatively low-temperature environments could improve sediment bioleaching at temperature regimes where mesophilic and thermophilic strains are not favoured. Such strains could be exploited for developing selective bioremediation procedures for sediments contaminated with As, to be applied in multistep biotreatment processes. 相似文献
18.
The amount of solid waste in the vicinity of the river Ganga increased rapidly during the festive days of Ardh-Kumbh. The
initial amount of solid waste was 775.0 kg, observed on 30th January 2004 in the Har Ki Pauri area, which increased to 4,550.0 kg
on the main bathing day of 4th May 2004, showing nearly a six-fold increase. The total amount of solid waste collected during
nine days of observations was 23,865.0 kg. The rate of solid waste generation fell sharply during the following week, after
the main bathing day, and was found to be 1,155.0 kg, which is still about 14.90% higher than the initial value. 相似文献
19.
为了分析洞穴滴水Ca2+、Mg2+和降雨、气温内在联系、进一步帮助解译周围地区地表环境,我们从2011年6月至2012年5月对贵州石将军洞滴水Ca2+、Mg2+等地球化学特征和周围气候进行了为期一年的监测,发现7个滴水点Ca2+、Mg2+年际变化趋势具有明显一致性,分为波动区、高值区及低值区,滴水点Mg/Ca比值与月降雨量没有明显一致性变化,但波动区,高值区及低值区均值与月降雨量具有很好的相关性,能够反应外界降雨量变化。并且研究发现,在低值区由于温度和土壤CO2的影响,造成滴水Ca2+、Mg2+在1月份突变性降低,成为年际变化的波谷期。 相似文献
20.
大连的旅游经济和吸引外资的环境因子修正系数的探讨 总被引:1,自引:0,他引:1
通过对大连的旅客及投资者的实地问卷调查 ,统计得出大连的旅游经济的环境因子修正系数为 0 .4 6 ,吸引外资的环境因子修正系数为 0 .2 2。 相似文献