BSZ-2型数字钟的检修方法

BSZ-2型数字钟目前仍应用于模拟地震观测中。本文介绍了该钟的工作原理，并对检修过程中常见问题进行了分析总结。     

基于B/S结构的地震信息管理系统设计

为满足地震科研与应急工作需要,建立基于B/S结构的地震信息数据库管理系统.该系统采用Oracle数据库、Java开发软件、Tomcat网站服务器组合开发,实现重点监视区域数据的共享及应用.     

基于遗传算法和统计学的电阻率测深二维反演研究

本文介绍了一种以遗传算法和统计学为基础的反演方法,该方法利用一维反演结果的统计学特征确定地层电性结构并设计初始模型,使用遗传算法修改模型,经过二维有限单元法正演达到拟合误差最小,从而完成电阻率测深数据的二维反演.这个方法的优点在于不需要解大型线性方程组,降低计算量,先判断地层电性结构,反演后给出用地电断面表示的直观的解释结果.理论模型试算和模型实验证明该方法效果较好.     

探讨利用SCIAMACHY数据反演温室气体二氧化碳

自工业革命以来CO2已经成为引起全球气候变暖的一种最主要的人为温室气体,由此引起的全球气候变化是当今社会经济可持续发展面临的最严峻挑战之一.为了更好的研究二氧化碳在时间与空间尺度上的格局及变化,综合分析CO2与太阳辐射、地面反照率、气溶胶等要素之间的关系,本文回顾了以往利用新型卫星传感器获取多源遥感数据的特点,分析了多种反演计算方法的优缺点,并结合地面实测数据进行对比分析的方法与理论,全面阐述国际上有关CO2柱浓度反演的思想.作者认为目前在地面观测站较少的情况下,针对先进的SCIAMACHY传感器数据利用DOAS相关算法及BESD算法进行CO2柱体浓度反演的数据连续,技术成熟,并由此提出了下一步工作中应解决的3个问题.     

三峡水库澎溪河流域高阳回水区夏季水体CO2分压日变化特性

水柱中CO2分压(pCO2)的时空分布在一定程度上可反映水中碳的环境地化特征.本研究在夏季分层期间对三峡水库澎溪河(小江)流域高阳回水区段进行了昼夜连续观测发现,恒定的温跃层中pCO2随水深增加而显著增大,表层0.5 m处pCO2均值为152±71μatm,而在水深10.0 m处pCO2均值为4568±1089μatm,同水温、pH及DO存在明显的负相关关系,进一步分析认为水温等将影响微生物、浮游植物的代谢过程及水气界面对流传输,进而对pCO2分布产生影响.对水气界面CO2扩散通量的估算结果表明,夏季分层期间高阳水域总体上表现为CO2的汇,其对大气CO2的吸收量最大值于15:00左右,达到-0.33 mmol/(m2.h);最弱在次日凌晨3:00左右,吸收量仅为-0.17 mmol/(m2.h).     

强震人员损失回归预测方法

在回顾近年对地震人员损失预测的研究工作的基础上,根据USGS的PAGER系统中地震人员损失回归模型,利用发生在1970-2008年间的128条地震现场调查灾害记录建立了我国东、西部区域适用的地震人员损失预测模型;并利用发生在1980-2007年间的234条地震损失记录建立了地震人员重伤数与人员死亡数的回归关系;最后利用模型对2008年四川汶川地震的人员损失进行评估计算,得到了与实际震害损失相接近的评估结果。     

Analysis of Stock Market Development and CO2 Emissions on OECD Countries via an Empirical Model

Accompanying economic growth, CO₂ emissions have polluted the natural environment worldwide. This study highlights the special problems with stock market development and CO₂ emissions in 25 Organization for Economic Cooperation and Development (OECD) countries during 1971–2007 to trace the trend of CO₂ emissions while countries grow their economies. A panel‐data model is applied to analyze the relationships between stock market (SM) development, energy consumption, gross domestic product (GDP), and CO₂ emissions in 25 OECD countries. Low‐GDP countries show different results from high‐GDP countries in the trends of SM development and CO₂ emissions, and dynamic effects occur in SM development and CO₂ emissions under various GDP conditions. There is a negative relationship between SM development and CO₂ emissions if countries enjoy high economic growth, which means that these countries avoid CO₂ emissions through SM development. However, a positive relationship is found between SM development and CO₂ emissions if countries experience low economic growth, which means that SM development does not show the boycott‐effect relationship with CO₂ emissions when countries experience low levels of economic development. This study shows a correlation between SM development and CO₂ emissions among OECD countries.     

贺兰山—银川地堑及邻区重力异常特征及构造意义

贺兰山—银川地堑及邻区地质结构复杂,对该区域深浅结构特征的研究具有重要意义.本文采用重力归一化总梯度成像和二维小波多尺度分解方法对研究区内重力异常进行了垂向和横向构造分析.重力归一化总梯度成像结果显示高低转换带的倾角、倾向与地质上的贺兰山东麓断裂、银川断裂和黄河断裂分布吻合较好,贺兰山西麓断裂与贺兰山东麓断裂汇交深度约18km,银川断裂与黄河断裂汇交深度约25km;二维小波多尺度分解成像结果表明正谊关断裂、贺兰山西麓断裂、芦花台断裂和银川断裂为上地壳断裂,贺兰山东麓断裂、青铜峡—固原断裂以及黄河断裂为下地壳断裂,且这三大断裂可能分别是阿拉善地块东南边界和鄂尔多斯地块西南边界;1739年平罗M8.0古地震震中与银川断裂在重力剖面深度约15km汇交,其垂向高低梯度为强变形带,同时古地震震中位于重力正负异常转换部位的低值区,据此可推断此次古地震的发震构造是银川断裂.这些结论可提高对贺兰山—银川地堑及邻区地质结构的认识,为该区地壳动力学过程及强震的孕震机理研究提供一定的科学依据.     

Calibration method affects the measured δ2H and δ18O in soil water by direct H2Oliquid–H2Ovapour equilibration with laser spectroscopy

The direct H₂O_liquid–H₂O_vapour equilibration method utilizing laser spectroscopy (DVE-LS) is a way to measure soil pore water stable isotopes. Various equilibration times and calibration methods have been used in DVE-LS. Yet little is known about their effects on the accuracy of the obtained isotope values. The objective of this study was to evaluate how equilibration time and calibration methods affect the accuracy of DVE-LS. We did both spiking and field soil experiments. For the spiking experiment, we applied DVE-LS to four soils of different textures, each of which was subjected to five water contents and six equilibration times. For the field soil experiment, we applied three calibration methods for DVE-LS to two field soil profiles, and the results were compared with cryogenic vacuum distillation (CVD)-LS. Results showed that DVE-LS demonstrated higher δ²H and δ¹⁸O as equilibration time increased, but 12 to 24 hr could be used as optimal equilibration time. For field soil samples, DVE-LS with liquid waters as standards led to significantly higher δ²H and δ¹⁸O than CVD-LS, with root mean square error (RMSE) of 8.06‰ for δ²H and 0.98‰ for δ¹⁸O. Calibration with soil texture reduced RMSE to 3.53‰ and 0.72‰ for δ²H and δ¹⁸O, respectively. Further, calibration with both soil texture and water content decreased RMSE to 3.10‰ for δ²H and 0.73‰ for δ¹⁸O. Our findings conclude that the calibration method applied may affect the measured soil water isotope values from DVE-LS.     

Water uptake of riparian plants in the lower Lhasa River Basin,South Tibetan Plateau using stable water isotopes

Riparian plants can adapt their water uptake strategies based on climatic and hydrological conditions within a river basin. The response of cold-alpine riparian trees to changes in water availability is poorly understood. The Lhasa River is a representative cold-alpine river in South Tibet and an under-studied environment. Therefore, a 96 km section of the lower Lhasa River was selected for a study on the water-use patterns of riparian plants. Plant water, soil water, groundwater and river water were measured at three sites for δ¹⁸O and δ²H values during the warm-wet and cold-dry periods in 2018. Soil profiles differed in isotope values between seasons and with the distance along the river. During the cold-dry period, the upper parts of the soil profiles were significantly affected by evaporation. During the warm-wet period, the soil profile was influenced by precipitation infiltration in the upper reaches of the study area and by various water sources in the lower reaches. Calculations using the IsoSource model indicated that the mature salix and birch trees (Salix cheilophila Schneid. and Betula platyphylla Suk.) accessed water from multiple sources during the cold-dry period, whereas they sourced more than 70% of their requirement from the upper 60–80 cm of the soil profile during the warm-wet period. The model indicated that the immature rose willow tree (Tamarix ramosissima Ledeb) accessed 66% of its water from the surface soil during the cold-dry period, but used the deeper layers during the warm-wet period. The plant type was not the dominant factor driving water uptake patterns in mature plants. Our findings can contribute to strategies for the sustainable development of cold-alpine riparian ecosystems. It is recommended that reducing plantation density and collocating plants with different rooting depths would be conducive to optimal plant growth in this environment.