广州市土地资源的保护和可持续利用研究   总被引：7，自引：1，他引：7  

陈朝辉  徐海清 《热带地理》1996,16(4):350-356

本文分析了广州市土地利用的结构及其变化趋势，指出土地利用上存在的主要问题和隐患 为采取有效措施，加强对耕地和环境的保护，以保证土地资源的可持续利用。  相似文献   

环境制图中数量特征的表示方法研究     

欧竹斌 《地理科学》1996,(1)

对环境制图中反映数量特征的定点符号法,包括几种连续和分级比率符号、非比率分级符号以及相关内容数量特征的表示进行了具体分析比较.对表示要素数量特征面状分布的网格法和等值线法,也结合实例进行了评述.  相似文献   

长周期地震观测中的环境干扰     

邱国荣 《地震地磁观测与研究》1992,13(2):61-66

文章根据长周期地震观测的理论和我国763长周期台网的观测实践,分析了长周期观测中的环境干扰。认为长周期观测对环境干扰(主要指温、湿度)敏感,但影响长周期仪器正常工作的关键是潮湿,尤其是记录室的潮湿。文章以763台网优秀台站的观测实践为例,认为只要掌握了环境干扰的规律,在防潮问题上采取有效措施,长周期地震观测是完全可以做到仪器工作稳定,管理得心应手。  相似文献   

春小麦单叶气孔行为及蒸腾作用的模拟   总被引：1，自引：0，他引：1  

郑海雷  黄子琛 《高原气象》1992,1(4):423-430

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Use of lichens in detecting environmental risk and in geochemical prospecting     

G. Dongarrà  D. Ottomello  G. Sabatino  M. Triscari 《Environmental Geology》1995,26(3):139-146

This paper provides data on variations in the contents of As, Sb, Ni, V, Pb, Cu, Cr, Au, Zn, Sc, and Al, measured in the thalli of a saxicolous lichen species,Xanthoria calcicola Ochsner s.l., collected in northeastern Sicily, near an industrial zone and along a belt crossing areas of known ores containing sulfides of heavy metals. A total of 91 lichen samples were collected on roof tiles (39) and on rocks (52). In the industrial zone, analysis of lichen thalli revealed high contents of nickel and vanadium, decreasing at increasing distances from the source of contamination. The results have also revealed the versatility ofXanthoria calcicola in geochemical prospecting for heavy metals such as Pb, Zn, As, Au, Sb, Ni, V, and Cu. The contents of these elements in the analyzed lichens highlight the same geochemical associations observed in prospecting surveys on samples of river sediments and identify similar anomalies. Interpretation of data in terms of enrichment factors (EFs) turned out to be particularly useful.  相似文献   

Barometric pumping effects on soil gas studies for geological and environmental characterization     

D. E. Wyatt  D. M. Richers  R. J. Pirkle 《Environmental Geology》1995,25(4):243-250

Data from two free soil gas sampling programs are evaluated for the effects of barometric pumping over time on measured soil gas volumes. One program collected data from the trapped atmosphere immediately above two hazardous waste landfill areas. Of these areas, one had extremely high soil gas emanations, whereas the other had a more modest soil gas release. The second experimental program involved the collection of free soil gas samples on a rough grid with an approximate spacing of 1.6 km over a 720-sq-km area. This reconnaissance effort was designed to establish regional soil gas background values and to establish the utility of this method as a geological mapping tool in the Atlantic Coastal Plain. Methane, ethane, propane, and hydrogen data are used for this study. The data suggest that there is a predictable change in soil gas volume with a given change in barometric pressure. The rate of change is greater with large soil gas volumes in permeable soils versus lower soil gas volumes in impermeable soils; however, a simple linear relationship seems to generate a predictable curve with a margin of error of approximately 50%. Furthermore, the results of this study indicate that barometric pumping effects should be strongly considered during soil gas screening efforts at hazardous waste sites as well as in regional studies for hydrocarbon source potential mapping.  相似文献   

在某污染的工业废物填埋场环境水文 地质评价中的同位素水文学研究     

王志明  肖丰  邓金贵  李森 《铀矿地质》1993,(6)

本文论述了某污染的工业废物填埋场场址的地质、水文地质条件,应用水化学方法、环境同位素技术(地下水中氚及氢、氧稳定同位素)和同位素单孔示踪技术等同位素水文学领域中的新方法对区内地下水的活动条件以及填埋场场址区分布的第四系孔隙潜水和第三纪红层孔隙-裂隙水的成因进行了分析,测量并确定了填埋场下部地下水的流速及流向。研究结果表明场区地下水的运动与地表水无直接水力联系。污染的工业废物填埋后不会通过地下水的迁移造成对地表水的污染,进而证实填埋场的地质、水文地质条件对处置污染的工业废物是安全可靠的。  相似文献   

Heavy Metal Load of Sediments of the River Gurk (Carinthia/Austria) — Merits and Limitations of Sequential Leaching Schwermetallbelastung des Sediments der Gurk in Kärnten — Vorzüge und Einschränkungen sequentieller Löseverfahren     

M. Sager  W. Vogel 《洁净——土壤、空气、水》1993,21(1):21-32

By means of the analysis of sediments cored in the small river Gurk (Carinthia/Austria), the input of Ag, Cd, Ce, Cr, Hg, La, Mo, Ni, V, and W from a chemical industrial plant could be detected. To estimate the actual load, and to obtain data for comparison with other sites, both unsieved fine sediments and sediments sieved to 20 μm were investigated from the same cores. Environmental mobilities of toxic heavy metals (Co, Cr, Cu, Ni, Zn) have been shown by sequential leaching following Tessier/Förstner. In the last step, HNO₃ leaches a purely geogenic fraction, which is fairly constant along the investigated river. Whereas the additional Cr from the input of the chemical plant is mainly found in the oxalate-leachable fraction, short-time-load to unpolluted sediments in the laboratory is found mainly in hydroxylamine/acetic acid. Both is due to the high affinity of Cr to Fe- and Mn-oxides. Adsorption/desorption experiments reveal that the low carbonate content of the Gurk sediments increases the importance of Fe/Mn-oxides for the sorption of Cr compared to other samples containing carbonate. The Ni-load was primarily found in weak-acid-leachable and oxalate-leachable fractions. Similarly, the oxalate-leachable fraction is dominant for adsorption of other metals and phosphorus. Other interelement relationships among the amounts leached, which are attributable partly to carbonate-, silicate-, organic or coating phases, have been found by means of factor analyses together with marker fractions for each type.  相似文献   

我国砷中毒病区的环境特征研究   总被引：18，自引：0，他引：18  

林年丰  汤洁 《地理科学》1999,19(2):135-139

我国饮水型砷中毒的流行屡见报道,台湾嘉南,新疆奎屯,内蒙古河套及山西大同等地是我国几个有代表性的病区。病区多为河湖相和滨海相沉积,粘土,粘土质淤泥和有机淤泥层发育,为富含有要质的还原环境,地下水中的含量一般为０．２－０．６ｍｇ／Ｌ。有时还有氟,腐殖酸,甲基胂酸和某些烷烃类等的有害有机化合物。  相似文献   

Photodegradation of pharmaceuticals in the aquatic environment: A review   总被引：6，自引：0，他引：6  

Anne?L.?Boreen  William?A.?ArnoldEmail author  Kristopher?McNeillEmail author 《Aquatic Sciences - Research Across Boundaries》2003,65(4):320-341

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