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中国典型季风海洋性冰川区雪坑中主要阴、阳离子的来源研究 总被引:1,自引:0,他引:1
Snowpacks samples were colleted from two glaciers: Baishui No.1 glacier and Hailuogou No.1 glacier in June, 2006. The method of sea-salt ions tracer, correlation analysis and trend analysis were used in this research in order to confirm the source of main ions, it is indicated that Na^+ is mainly from marine moisture and other ions mainly originate from land dust. The non-marine source percent of Cl^-, NO3^- , SO4^2-, K^+, Ca^2+ and Mg^2+ is 52%, 99%, 100%, 98%, 99.9% and 83%, respectively, in Hailuogou No.1 glacier, while the corresponding value in Baishui No.1 glacier is 68%, 99%, 100%, 98%, 99% and 59%. The non-marine source of ions is from dust of Central Asia arid regions carried by westerly circulation and the plateau borne-areas with Qinghai-Tibet Plateau winter monsoon in two glacial areas. However, the import of local dust in glacial area has made a great contribution to ions concentration in Baishui No.1 glacier, which accounts for the reason why the ions concentration in Baishui No.1 glacier is much higher than that of Hailuogou No.1 glacier. It is obvious that the source of each ion is different between Hailuogou No.1 glacier and Baishui No.1 glacier. There are three reasons which can explain it: firstly, the difference in the internal environment of glacial area, such as lithology, mountain-valley wind system, topographical relief and so on; secondly, the influence exerted by ions elution in snowpacks section, and ions elution in Hailuogou No.1 glacier is very strong; and thirdly, the difference caused due to varying ions transporting styles, deposition modes, chemical characteristics and post-ions-deposition process. 相似文献
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广西环江流域硫污染农田的土壤酸化与酸性土壤分布 总被引:8,自引:0,他引:8
矿业活动通过多种途径将矿石中伴生的还原态硫带入土壤而导致周边土壤酸化, 是目前矿山周边普遍面临的重要环境问题。本文以广西环江为例, 探寻大面积农田酸化的原因和 酸度分布特征。研究结果表明: 矿物组成分析(X-ray)、硫形态分析(EXAFS) 和同位素分析 结果表明: 环江农田土壤酸化的原因是洪水携带含硫尾砂进入农田, 还原态硫氧化产酸导致 土壤酸化。由于矿渣中还原态硫的污染, 受污染土壤的酸度、铁和硫的浓度显著高于未受矿渣污染的土壤。大环江沿岸出现不同的污染特征: 上游土壤的Fe, SO42- (SS)和St 含量较高, 但土壤尚未发生明显酸化; 中下游农田土壤H+ 和SO4 2- 含量较高, 土壤发生明显的酸化现象, 还存在继续酸化的风险。土壤受还原态硫污染后, 如果将旱地改为水田, 则可以降低土壤还原态硫的氧化速度和减缓酸化速度。 相似文献
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基于相同结构不同设计参数的高桩码头建立计算模型,研究两种结构自身动力特性的差异以及在地震作用下抗震性能的差异。研究表明:在相同荷载条件、场地条件、材料用量的前提下六桩码头的刚度要大于八桩码头;天津波作用下六桩码头的桩身加速度响应较大,且两种结构桩身加速度差异值随着震度的增大而增大;在相同峰值的罕遇地震下六桩码头的桩顶位移响应要小于八桩码头,而其残余位移要大于八桩码头;相同荷载条件下八桩码头的延性能力明显强于六桩码头,其极限塑性率是六桩码头极限塑性率的2.28倍;八桩码头在峰值加速度为800gal地震作用下达到极限曲率,六桩码头在峰值加速度为1 150gal的地震作用下达到极限曲率。 相似文献
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农产品质量溯源系统的研究 总被引:2,自引:0,他引:2
主要针对传统农产品质量追溯系统存在的广度较窄、精度不细致等问题,依托"热带特色农产品溯源系统"项目,利用无线射频识别技术,设计并实现农产品质量溯源系统,给出农产品质量溯源系统总体架构以及主要设计流程,并对标签转换、数据同步等关键技术进行阐述。 相似文献
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辽宁省中、新生代盆地深层地热地质条件良好,复杂的地质构造以及理想的地层岩性决定了其深层地热资源的成生.综合各盆地的地热地质条件,考虑深大断裂的发育及影响地段,以及热储层的岩性,同时兼顾所处的地理位置,最后圈定五大盆地中十个地段为勘察的有利地段,为地热井施工井位的选择提供了有利的地质条件. 相似文献
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Changes of the Hailuogou Glacier, Mt. Gongga,China, against the Background of Global Warming in the Last Several Decades 总被引:2,自引:0,他引:2
Great change, associated with global warming, has occurred at the Hailuogou (海螺沟)has retreated 1 822 m in the past 106 years, with an annual mean retreat of 17.2 m, and the front elevation has risen by 300 m since 1823. Comparison of glacier variations and temperature fluctuations in China and the Northern Hemisphere, over the last 100 years, indicates that glacier retreat stages occurred during the warm phase, and vice versa. Mass balance records during 1959/60--2003/04 have shown that the glacier has suffered a constant mass loss of snow and ice. The accumulated mass balance, -10.83 m water equivalent, indicates an annual mean value of -0.24 m water equivalent. The correlation between the mass balance and temperature is significant, which also indicates that climate warming is the crucial cause of glacier loss.Local hydrological and climatic data demonstrate that runoff from the glacier has been increasing both seasonally and annually.The correlation analysis and trend analysis indicate that ice and snow melted water is the main cause of an increase in the runoff. As the climate has become warmer, changes in the glacier surface morphology have obviously occurred. These include a decrease in glacier thickness, enlargement of glacial caves, and reduction of the size of clefts on the glacier surface. The ablation period has lengthened and the ablation area has expanded. A variety of factors thus provide evidence that the Hailuogou glacier has suffered a rapid loss of snow and ice as a result of climatic warming. 相似文献