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81.
Malgorzata Kwiecień 《Environmental monitoring and assessment》1997,46(3):191-207
A new, direct method was developed for quantifying inorganic particulate aerosols trapped by the forest canopy, and for determining the resulting input of elements to a forest ecosystem. The method is based on direct measurements of only six parameters. Using this method, it is possible to determine the load of aerosols trapped by the forest canopy and deposited to leaves, as well as the load of aerosols falling to the forest floor by impaction on plants. It is also possible to estimate the aerosol input of soluble and insoluble elements to an ecosystem. With this new method it has been found that the load of aerosols trapped by the canopy of a mixed forest located in the Rybnik Coal Basin averaged 189.0 kg x ha-1 x growing season-1, or 39.3% of the total inorganic particles reaching the ecosystem. The trapped aerosols provided 13.4 kg x ha-1 of soluble nitrogen and 0.91 kg x ha-1 of insoluble nitrogen over the growing season. At the same time, the input of soluble nitrogen from the atmosphere with rainfall to an open area averaged 13.9 kg x ha-1, and the input of insoluble nitrogen with inorganic dusts averaged 1.4 kg x ha-1. 相似文献
82.
茶尘(大叶种)分散度的测定 总被引:1,自引:0,他引:1
论述了利用图像分析系统对茶尘(大叶种)分散度的测定,得到了分散度的结果,并对测定结果进行了讨论. 相似文献
83.
Accumulation of metals in deciduous tree foliage fromurban areas in western-south Poland was monitored duringthe vegetation season of 2000 year. Concentrations of Al,Ba, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sr, Ti and Znwere measured in birch, willow, linden and maple leavesusing the ICP-AES method. Seasonal variations of metalconcentrations and their relations with sampling sitewere investigated. The most dynamic accumulation of Al,Cd, Cr, Ni and Pb was observed for examined species. Thehighest differences in element concentrations forinvestigated sites were found for Ba, Cd, Mn and Ni.Interelement correlations were investigated. In allfoliar samples synergistic relationships between Al–Crand Ca-Sr were found. Statistically significant negativecorrelations were observed only for Cd and Ti in birch leaves. 相似文献
84.
九华山佛茶文化旅游开发研究 总被引:3,自引:0,他引:3
九华山佛茶文化旅游既有历史优势,又有区位优势,开发九华山佛茶文化旅游是将九华山的佛教旅游资源与茶文化旅游资源中的寺院茶文化相结合。更新观念、重视特形象设计、丰富完善旅游产品、加大旅游商品开发和不断开拓旅游市场等是九华山佛茶文化旅游开发的重要举措。 相似文献
85.
针对我国在用车排放比较严重的现状,我们认为:短期内易于实现,花费不高,不用对现有车辆作重大技术变动的有效措施是完善在用车I/M计划和进行在用国的加速淘汰工作。而且,对于用率和高污染车辆,完善的I/M计划也是更有效控制机动车排放污染所必需的。 相似文献
86.
Chandrajith R Abeypala U Dissanayake CB Tobschall HJ 《Environmental geochemistry and health》2007,29(5):429-434
The purpose of this study was to assess the fluoride content of Ceylon Tea, which is a popular beverage throughout the world.
The fluoride content of tea infusions prepared from different grades of tea leaves collected from different parts of the tea-growing
regions (25 samples) of Sri Lanka was measured using a fluoride-selective electrode. Fluoride leaching was found to vary from
0.32 to 1.69 mg F/l, but there were no significant differences in terms of fluoride leaching between tea from different tea-growing
regions or between tea of different grades. Dental fluorosis is widespread throughout the dry zone of Sri Lanka, and drinking
water has traditionally been considered to be the main contributory factor to the development of fluorosis. However, diet,
the consumption of tea in particular, may also contribute to the manifestation of dental diseases. 相似文献
87.
Weather,climate, politics,or God? Determinants of American public opinions toward global warming 总被引:1,自引:0,他引:1
Wanyun Shao 《环境政策》2017,26(1):71-96
2012 American National Election Study data supplemented with monthly temperature data from the United States Historical Climatology Network are used to examine how religion, politics, and weather and climate affect views of global warming. Evangelical fundamentalism is the most consistent factor among all religion-related variables in determining perceptions of global warming, those more oriented toward evangelical fundamentalism being less likely than others to believe in the existence, anthropogenic cause, and adverse impact of global warming. Controlling for the effects of traditional political predisposition variables, including party identification and political ideology, support for the Tea Party plays a dominant role in determining views of global warming; support for the Tea Party leading to higher likelihood of disbelief in the existence, anthropogenic cause, and negative impact of global warming. Warming winters coupled with cooling springs of the past decade are positively related with belief in the existence of global warming. 相似文献
88.
茶渣生物炭制备及其对溶液中四环素的去除特性 总被引:9,自引:6,他引:3
以茶渣(tea waste)为对象,在300、 500和700℃限氧条件下热解制备成生物炭(TWBC300、 TWBC500和TWBC700),研究其对溶液中四环素(tetracycline,TC)的去除特性.采用元素分析、比表面积分析仪、傅里叶红外光谱(FTIR)和X射线光电子能谱(XPS)对TWBC300、 TWBC500及TWBC700进行表征;考察生物炭添加量、溶液初始pH、离子类型及强度等因素对四环素去除效果的影响;结合吸附动力学、吸附等温线和仪器表征结果探究生物炭对溶液中四环素的作用机制.结果表明,适合的生物炭投加量为4.0g·L~(-1).溶液初始pH对生物炭去除四环素的影响较小.溶液中阳离子类型对生物炭吸附四环素的抑制作用依次是Mg~(2+)Ca~(2+)K~+Na~+.NH~+_4能略微促进生物炭对四环素的吸附,而铜离子却显著抑制生物炭对四环素的去除.环境温度增加能提升生物炭对四环素的去除效果.拟二级动力学方程和Langmuir模型可以较好地拟合茶渣生物炭吸附四环素的过程.茶渣生物炭对四环素的吸附量依次是TWBC700TWBC500TWBC300.孔隙扩散、氢键和π-π作用是茶渣生物炭去除四环素的主要机制.因此,高温制备的茶渣生物炭可作为废水中四环素去除的良好吸附剂. 相似文献
89.
90.
基于GIS的贵州省茶园生态适宜性研究 总被引:3,自引:0,他引:3
通过利用GIS技术,在土地利用现状以及喀斯特空间分布的基础上初步划分茶叶种植适宜地和不适宜地。选择对茶叶生长密切相关的地形地貌(海拔、坡度、坡向)、气候条件(光、热、降水条件及空气相对湿度)及土壤条件(土壤pH值)等8个生态评价因子,通过专家打分确定各因子权重,应用GIS空间叠加分析模块实现贵州茶园生态适宜性评价。结果表明:贵州省适宜茶叶种植的面积为32417.00km2,占国土面积的18.40%,其中非常适宜种植茶叶的区域面积为10618.00km2,占国土面积的6.03%;适宜种植茶叶的区域面积为11554.00km2,占国土面积的6.56%;比较适宜种植茶叶的区域面积为10245.00km2,占国土面积的5.81%;不适宜种植茶叶的区域面积为143735.45km2,占国土面积的81.60%。以上评价结果将为贵州茶产业的大力发展提供科学依据和技术基础。 相似文献