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Crustaceous lichens sensitive monitor of caesium-137 radiation level in terrestrial environment 下载免费PDF全文
<正> The activity of caesium-137(Bq/kg)in the crustaceous lichens and othersamples was determined to prove the feasibility that crustaceous lichens work as a sen-sitive biology monitor to record the caesium-137(Bq/kg)radiation levels of terrestri-al environment.The measurements were performed with GEM series HPGe(high-pu-rity Germanium)coaxial detector system(ADCAM-100)made by EC & GORTECCompany in USA.It was found that the activity of caesium-137(Bq/kg)in the cru-staceous lichens was one order of magnitude higher than that found in surface soil,and was over three orders of magnitude higher than those found in the familiar biologi-cal samples.These results proved that crustaceous lichens may be one of the mostsensitive biolog-ical monitors about the remote transmission and environmental radia-tion levels of caesium-137. 相似文献
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The~(137)Cs activity and its geographical significance in terrestrial ecosystem of Great Wall Station, Antarctica 下载免费PDF全文
The radioactive isotope 137 Cs is one of the important tracers for studying the physical processes and the human impacts on the environment. Based on the investigation results of the terrestrial ecosystem of Great Wall Station, Antarctica, it was shown that there are some artificial radioactive elements 137 Cs in Antarctic terrestrial ecosystem. The sequence of 137 Cs specific activities is as follows: crustaceous lichen>fruticose lichen>surfacemoss>surface soil, and the crustaceous lichen is one of the most sensitive ways in monitoring the impact of the longterm diffusion of 137 Cs on the environment. 相似文献
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山东省耕地资源安全问题研究 总被引:10,自引:0,他引:10
构建耕地资源安全概念模型,通过对人口资源压力极值状态下的耕地资源安全需求与可能供给之间的综合平衡,分析山东省耕地资源安全态势。2004年山东省耕地总量为754万hm2,预测2020年全省耕地资源的安全需求量为747万hm2,同期各种原因将减少耕地42.5万hm2,后备耕地潜力为50万hm2。理论上可保障耕地资源安全,但实践操作难度较大,据此提出保障山东省耕地资源安全的相应对策。 相似文献
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滦河源区东沟小流域土壤风蚀特征分析 总被引:8,自引:5,他引:8
土壤风蚀是世界许多地区面临的一个严峻环境问题,土壤风蚀特征是建立土壤风蚀预报模型,制定土壤风蚀防治措施的基础信息,综合考察了湾河源区东沟小流域地理环境特征,分析了不同风蚀强度下暗粟钙土的诊断特性,其结果表明,自然环境提供了土壤风蚀的物质条件,区域日益强化的农牧业及砍薪材活动则是土壤风蚀的触发驱动力;失去植被保护的干旱松散表土,在大风驱动下,其中的细砂和极细砂(0.01-0.10mm)首先以跃移,悬浮方式流失,而粗砂(2-0.25mm)则相对是非可风蚀颗粒;建立了定量刻划土壤风蚀相对强度指数,即SWEI=粗砂含量/风蚀粒子含量,东沟小流域自然暗粟钙土表土SWEI≤2.0,轻度风蚀区表土SWEI≥3.0,重度风蚀区表土SWEI≥9.0,而在风积区表土SWEI≤1.5,该指标较好地反映了区域土壤风蚀强度的差异性。 相似文献
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The activity of caesium-137 (Bq/kg) in the crustaceous lichens and other samples was determined to prove the feasibility that crustaceous lichens work as a sensitive biology monitor to record the caesium-137 (Bq/kg) radiation levels of terrestrial environment. The measurements were performed with GEM series HPGe ( high-purity Germanium) coaxial detector system (ADCAM -100 ) made by EC & GORTEC Company in USA. It was found that the activity of caesium-137 (Bq/kg) in the crustaceous lichens was one order of magnitude higher than that found in surface soil, and was over throe orders of magnitude higher than those found in the familiar biological samples. These results proved that crustaceous lichens may be one of the most sensitive biological monitors about the remote transmission and environmental radiation levels of caesium-137. 相似文献
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南析乔治王岛菲尔德斯半岛土壤矿物化学风化特征分析 总被引:1,自引:0,他引:1
本文在考察菲尔德斯半岛土环境、土壤理化性状的基础上部分析了本区性土壤的粘土矿物组成粘粒和全土中土壤大量元素的含量,认为亚南极海洋性气候区土壤次生粘土矿物主要是蒙中石、伊利石和绿泥石;土壤矿物风化过程包括脱盐基,周期性滞水氧化-还原脱铁锰和微弱的脱硅过程。 相似文献