硅酸盐类样品中硅、铁、铝、钛、锰、钙、镁、钾、钠和磷的x射线荧光光谱测定

本文拟定了一种以熔融法制备样片,用X射线荧光光谱测定硅酸盐类样品中Si、Fe、Al、Tj、Mn、Ca、Mg、K、Na、P等元素的分析方法。在对不同靶材X光管和分光晶体实验对比的基础上,选择了最佳的测量条件。该法具有快速、准确,测量范围广,检测限低,价格便宜等优点。经过近百个各种类型标样或管理样品的分析对比表明,本法不仅适用于硅酸盐类岩石样品的分析,还适用于铁矿、铝土矿、碳酸盐类岩矿样品以及水泥、耐火材料等样品的分析。     

西苏门答腊实武牙地区晚三叠世花岗岩锆石年代学及其特提斯构造意义

苏门答腊岛位于东特提斯构造域,沿该岛分布了大量不同时代和成因的花岗岩,但这些花岗岩的形成时代和延伸以及对比均未能得到很好的界定,也限制了对东南亚主要岩浆岩带延伸及其构造背景的理解.对西苏门答腊实武牙地区新识别出的花岗岩体开展了精细的LA-ICP-MS锆石U-Pb年代学研究.结果显示,3个花岗岩样品的锆石均为典型的岩浆成因,其岩浆年龄分别为215.1±2.4 Ma（MSWD=0.14）、206.1±5 Ma（MSWD=0.22）、214.3±5 Ma（MSWD=0.11）,锆石年代学研究表明西苏门答腊存在晚三叠世的岩浆作用.对比东南亚花岗岩省内同期侵入岩认为,西苏门答腊实武牙地区的晚三叠世花岗岩可与东南亚西部花岗岩省进行对比和联系,该套晚三叠世花岗岩可能形成于中特提斯洋初始俯冲的弧后裂谷环境.      

珠江口沉积柱样^210Pb法年龄测定结果及其环境地球化学意义

提供了珠江河口及河道１０个沉积柱＾２１０Ｐｂ法的ＣＦ模式（稳恒放射性通量模式）和ＣＡ模式（稳恒初始放射性模式）的年龄测定结果,并据此讨论珠江三角洲近百年来沉积环境的演化,研究结果表明,西江河道和珠江广州河道１９８０年以前沉积速率为０．５－１．０ｃｍ／ａ．１９８０年以后沉积速率增长加快,９０年代达到４－６ｃｍ／ａ,沉积通量为４－６ｇ／（ｃｍ＾２．ａ）河口沉积速率逐年增长趋势,但一般比河道柱样小得多,     

舒城县东部地区地下水环境质量评价与污染分析

根据舒城东部地区地下水环境实地调查结果,本文选取78个地下水样,按埋深10m以浅、10m以深进行地下水质量分类评价和污染分析.结果表明:①地下水水质绝大部分为Ⅳ类、Ⅴ类水,地下水污染非常严重,主要污染因素是Fe、Mn、Al、Hg、NO3-和氨氮等.②埋深10m以浅的地下水水质主要是Fe、Mn、Al、Hg、NO3-和氨氮...     

Evapotranspiration management based on the application of SWAT for balancing water consumption: A case study in Guantao,China

Rapid social and economic development results in increased demand for water resources. This can lead to the unsustainable development and exploitation of water resources which in turn causes significant environmental problems. Conventional water resource management approaches, such as supply and demand management strategies, frequently fail to restore regional water balance. This paper introduces the concept of water consumption balance, the balance between actual evapotranspiration (ET) and target ET, and establishes a framework to realize regional water balance. The framework consists of three stages: (1) determination of target ET and actual ET; (2) quantification of the water-saving requirements for the region; and (3) reduction of actual ET by implementing various water saving management strategies. Using this framework, a case study was conducted for Guantao County, China. The SWAT model was utilized to aid in the selection of the best water saving management strategy by comparing the ET of different irrigation methods and crop pattern adjustments. Simulation results revealed that determination of SWAT model parameters using remote sensing ET is feasible and that the model is a valuable tool for ET management. Irrigation was found to have a greater influence on the ET of winter wheat as compared to that of maize, indicating that reduction in winter wheat cultivation is the most effective way to reduce regional ET. However, the effect of water-saving irrigation methods on the reduction of ET was not obvious. This indicates that it would be difficult to achieve regional ET reduction using water-saving irrigation methods only. Furthermore, selecting the best water saving management strategy by relying solely on the amount of reduced ET was insufficient, because it ignored the impact of water conservation measures on the livelihood of the agricultural community. Incorporating these considerations with our findings, we recommend changing the current irrigation method to sprinkler irrigation and replacing 20% of the winter wheat-maize cultivated area with cotton, as the best strategy to achieve water balance in the study area.     

香草坪花岗岩体年代学和地球化学特征

香草坪岩体主要岩性为中粗粒斑状黑云母花岗岩,SHRIMP锆石U-Pb法年龄为211±2Ma,属于印支期岩浆作用产物。岩石地球化学特征研究表明,其ACNK,微量元素模式图曲线形态总体向右倾,以及轻稀土富集、Eu明显亏损的稀土配分模式曲线特征,与华南S型花岗岩的地球化学特征相似。该岩体高(87Sr/86Sr)i和低εNd(t)的特点,表明其可能是前寒武系中等成熟度的基底岩石经部分熔融形成的。该区基底岩石较高的铀含量,可为香草坪岩体提供充足的铀元素,形成铀元素的初始富集。     

Spatial and temporal variation of organic carbon in the northern South China Sea revealed by sedimentary records

Three sediment cores were taken from the Pearl River estuary and adjacent northern South China Sea (SCS). These sediment cores span the time interval 1900–2000 AD. The stratigraphy of the concentration, the ratio of total organic carbon (TOC) to total nitrogen (TN) and stable isotope (δ¹³C_org) of organic carbon (OC) from three high-resolution sediment cores were analyzed. The stratigraphic profiles of OC concentration, TOC/TN ratios and δ¹³C_org for the near past 100 yrs indicate that terrestrial organic matter decreases from 68.3% to 27.4% of the TOC in the Pearl River estuary, while Dapeng Bay (offshore east of Hong Kong) apparently had throughout little terrestrial organic matter input. The highest deposited OC occurs at the Humen River mouth and the OC concentrations are higher in the outer estuary than in the inner shelf of the northern SCS. The deposited OC at the River mouth increased with time, which could be caused by the high precipitation of land-derived organic matter and the high input of terrestrial organic matter, which is likely related to the rapid urbanization and industrial development in the Pearl River Delta since the 1970s. The OC concentrations did not exhibit an obvious increase with time in most areas of the Pear River estuary and adjacent inner shelf of the SCS, but the algal-derived OC concentration inferred from the δ¹³C_org values increased with time especially from 1980 to 2000 in the outer Pearl River estuary and Dapeng Bay. This increase is presumably caused by enhanced primary marine productivity supported by higher anthropogenic nutrient inputs.     

Climate change in the 21st century simulated by HadGEM2-AO under representative concentration pathways

We present climate responses of Representative Concentration Pathways (RCPs) using the coupled climate model HadGEM2-AO for the Coupled Model Intercomparison Project phase 5 (CMIP5). The RCPs are selected as standard scenarios for the IPCC Fifth Assessment Report and these scenarios include time paths for emissions and concentrations of greenhouse gas and aerosols and land-use/land cover. The global average warming and precipitation increases for the last 20 years of the 21st century relative to the period 1986-2005 are +1.1°C/+2.1% for RCP2.6, +2.4°C/+4.0% for RCP4.5, +2.5°C/+3.3% for RCP6.0 and +4.1°C/+4.6% for RCP8.5, respectively. The climate response on RCP 2.6 scenario meets the UN Copenhagen Accord to limit global warming within two degrees at the end of 21st century, the mitigation effect is about 3°C between RCP2.6 and RCP8.5. The projected precipitation changes over the 21st century are expected to increase in tropical regions and at high latitudes, and decrease in subtropical regions associated with projected poleward expansions of the Hadley cell. Total soil moisture change is projected to decrease in northern hemisphere high latitudes and increase in central Africa and Asia whereas near-surface soil moisture tends to decrease in most areas according to the warming and evaporation increase. The trend and magnitude of future climate extremes are also projected to increase in proportion to radiative forcing of RCPs. For RCP 8.5, at the end of the summer season the Arctic is projected to be free of sea ice.     

The South China Sea Monsoon Experiment(SCSMEX) Implementation Plan

ＴｈｅＳｏｕｔｈＣｈｉｎａＳｅａＭｏｎｓｏｏｎＥｘｐｅｒｉｍｅｎｔ（ＳＣＳＭＥＸ）ＩｍｐｌｅｍｅｎｔａｔｉｏｎＰｌａｎＤｉｎｇＹｉｈｕｉ（丁一汇），ＣｈａｏＱｉｎｇｃｈｅｎ（巢清尘），ＺｈａｎｇＹａｎ（张雁），ＧａｎＺｉｊｕｎ（甘子钧）①ａｎｄＺｈａ...     

小波的SAR和光学图像融合方法比较研究

本文通过光学图像和SAR图像的融合,对几种典型的小波融合方法进行了分析对比实验,并使用各种评价标准对它们的融合效果给出了评价。在此基础上,对光学图像和SAR图像融合效果的各种评价标准做出了讨论并提出自己的看法。