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11.
本次调查中共记录到35种植物,其中矿区28种植物,非矿区27种植物。矿区和非矿区共有种有20种。测定同时出现在矿区及非矿区的8种植物的荧光动力学曲线,发现白莲蒿(A.sacrorum)、臭椿(Ailanthus altissima)、杠柳(Periplo-ca sepium)、黄栌(Cotinus coggygria)及荆条(Vitex negundo Var.Canna-bifolia)在矿区和非矿区生长状况差异不显著。胡枝子(Lespedeza bicolo)、酸枣(Ziziphus jujuba var.spinosa)及榆树(Ulmus pumila)在矿区生长良好,这说明矿区恶劣的土质条件虽然影响着一些植物的生长,但是良好的光照条件却为这些植物的生长提供更多的机会。  相似文献   
12.
A process based life cycle assessment of dimension stone production in the UK has been carried out according to PAS 2050. From a survey of eight production operations, on a cradle-to-site basis for UK destinations the carbon footprint of sandstone is 77 kgCO2e/tonne, that of granite is 107 kgCO2e/tonne and that of slate is 251 kgCO2e/tonne. These values are considerably higher for stone imported from abroad due to the impact of transport. Reducing the reliance on imported stone will contribute to emissions reduction targets as well as furthering the goals of sustainable development.  相似文献   
13.
石林风景区旅游环境容量研究   总被引:6,自引:0,他引:6  
研究旅游环境容量,要以生态、环境质量、设施、游客感应和客流分布5类指标为依据。据此分析,石林风景区游览容量有余而住宿、交通容量不足。应通过合理分布客流和扩大交通、住宿容量使其到2000年形成游览容量15000人/天,交通容量14000人/天和住宿容量8000人/天的旅游环境容量构成。  相似文献   
14.
兴文石林是喀斯特岩溶地质风景名胜区兴文石海的中心景区,喀斯特岩溶山地的生态环境具有一定脆弱特性。随着旅游业的不断发展,景区加大了开发力度,可能导致景区脆弱性的加剧,为了保证在旅游开发中能对景区重要的地质资源进行更好地保护。采用生态脆弱区评级指标厦权重值评分法对兴文石林的10个主蒂点进行了研究,分析得出,兴文石林存在轻生态脆弱性、中生态脆弱性和强生态脆弱性三种梯度趋向,其中,脆弱性最强区域面积达到2平方公里的面积,这些区域分布在景区的边缘地带,因此。要实现旅游资源的可持续利用,必须对强生态脆弱性区域实行禁游和实行退耕还林等措施,以防止脆弱区域的扩大和脆弱性加剧。  相似文献   
15.
Environmental management of the stone cutting industry   总被引:1,自引:0,他引:1  
Environmental Management of the stone cutting industry in Hebron is required to reduce the industry's adverse impact on the downstream agricultural land and the adverse impact on the drinking water aquifers. This situation requires the implementation of an industrial wastewater management strategic approach and technology, within the available technical and financial resources. Ten pilot projects at different locations were built at Hebron to reduce or eliminate the incompatible discharge of the liquid and solid waste to the environment and improve the stone cutting industry's effluent quality. A review of existing practices and jar test experiments were used to optimize the water recycling and treatment facilities. The factors reviewed included influent pumping rates and cycles, selection of the optimal coagulant type and addition methods, control of the sludge recycling process, control over flow rates, control locations of influent and effluent, and sludge depth. Based on the optimized doses and Turbidity results, it was determined that the use of Fokland polymer with an optimal dose of 1.5mg/L could achieve the target turbidity levels. The completion of the pilot projects resulted in the elimination of stone cutting waste discharges and an improvement in the recycled effluent quality of 44-99%. This in turn reduced the long term operating costs for each participating firm. A full-scale project that includes all the stone cutting firms in Hebron industrial area is required.  相似文献   
16.
Qin HB  Zhu JM  Su H 《Chemosphere》2012,86(6):626-633
A high degree of association between Selenium (Se) and organic matter has been demonstrated in natural environments, but Se fractions and speciation in organic matter is unclear. In this study, a method for quantifying organic matter associated with Se (OM-Se) was developed to investigate Se fractions in organic matter in Se-rich soils and weathered stone coal from Enshi, China, where Se poisoning of humans and livestock has been documented. Initially, Se was extracted using water and a phosphate buffer. Subsequently, OM-Se was extracted using NaOH, and then speciated into Se associated with fulvic acids (FA-Se) and humic acids (HA-Se). Both FA-Se and HA-Se were further speciated into the weakly bound and strongly bound fractions using a customized hydride generation reactor. The results show that FA-Se (1.91-479 mg kg−1) is the predominant form of Se in all Se-rich soils and the weathered stone coal samples, accounting for more than 62% of OM-Se (3.07-484 mg kg−1). Weakly bound FA-Se (1.33-450 mg kg−1) was prevalent in the total FA-Se, while weakly bound HA-Se (0.62-26.2 mg kg−1) was variable in the total HA-Se (1.15-32.5 mg kg−1). These data indicate that OM-Se could play a significant source and sink role in the biogeochemical cycling of Se in the supergene environment. Weakly bound FA-Se seems to act as a potential source for bioavailable Se, whereas strongly bound HA-Se is a possible OM-Se sink which is not readily transformed into bioavailable Se.  相似文献   
17.
针对<红楼梦>第70回中记载的海啸,利用多种历史海啸资料进行了分析,结果表明,其提出的海啸系1751年3月15日(农历),在掖县、维县、平度、昌邑发生的海啸.  相似文献   
18.
对溧水神仙洞的发掘和进行地质、地貌、孢粉、古脊椎动物与古人类、C14 年代及考古等多学科综合研究结果表明 :该洞是石炭系石灰岩沿层面裂隙经地下水溶蚀而成 ;洞穴堆积物的时代应属全新世早期 ,或新石器时代早期 ,绝对年代距今约为 1.1万年。其中发现的动物群为我国南方晚更新世动物群向现代动物群过渡的类型 ,而代表中 -晚更新世的最后鬣狗与代表新石器时代文化标志的陶片共生 ,为我国第四纪时代的划分 ,或新、旧石器时代文化的划分提供了重要依据。陶片则迄今为止是我国具有完整地层层位记录的最古陶片。它的发现 ,不仅将我国新石器时代文化大大推前 ,更为重写中华古史 ,校正“中华五千年文明”的提法 ,将中华文明追溯到一万年前并重排世界古文明位次增加了依据。同时 ,智人颞骨的发现 ,对长江中、下游古人类的研究 ,也提供了新的资料  相似文献   
19.
针对目前国内外碎石桩复合地基抗液化判别方法的研究现状进行了简要归纳和分析 ,其研究结果表明 :已有的判别方法存在着较大的局限性 ,还不能很好地反映碎石桩的排水效应、减震效应及各效应的综合作用 ;桩径、桩长、桩距等加固参数对加固效果的影响还不能在判别标准中得到合理的体现。最后 ,笔者对今后的研究工作提了几点建议  相似文献   
20.
The traditional defence against propagating coal dust explosions is the application of dry stone dust. This proven and effective safety measure is strictly regulated based on extensive international experience. While new products, such as foamed stone dust, offer significant practical benefits, no benchmark tests currently exist to certify their dust lifting performance in comparison to dry stone dust. This paper reviews the coal dust explosion mechanism, and argues that benchmark testing should focus on dust lifting during the initial development of the explosion, prior to arrival of the flame. In a practical context, this requires the generation of shock waves with Mach numbers ranging from 1.05 to 1.4, and test times of the order of 10's to 100's of milliseconds. These proposed test times are significantly longer than previous laboratory studies, however, for certification purposes, it is argued that the dust lifting behaviour should be examined over the full timescales of an actual explosion scenario. These conditions can be accurately targeted using a shock tube at length scales of approximately 50 m. It is further proposed that useful test time can be maximised if an appropriately sized orifice plate is fitted to the tube exit, an arrangement which also offers practical advantages for testing. The paper demonstrates this operating capability with proof-of-concept experiments using The University of Queensland's X3 impulse facility.  相似文献   
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