广西沙田柚农业地质

沙田柚生长好坏、产量品质高低 ,与所在地质环境有密切关系 ,种植在碎屑岩和花岗岩环境区及河流阶地、江心洲、山麓地貌环境区的沙田柚 ,长势好、产量品质高。种植在碳酸盐岩环境区及山坡型、岩溶洼地地貌区的沙田柚 ,长势差、产量品质低。影响沙田柚长势、产量品质的关键元素是Na,Na是沙田柚的特需元素。     

电测深ρ＿s差值法的应用效果

用电测深研究地电断面、寻找隐伏多金属矿体时，以往采用ρ＿ｓ（或η＿ｓ）等值线断面图进行地质推断解释，因受浅源信号的干扰，效果差。本文提出了采用ρ＿ｓ（或η＿ｓ）差值法，能排除浅源干扰信号，反映出地电断面的相对变化，突出了深部微弱信息，取得了较好的地质解释效果。     

南疆盆地沙尘气溶胶光学特性及我国沙尘天气强度划分标准的研究

依据气溶胶光学厚度测量原理,利用布设于塔里木盆地腹地塔中和盆地西南边缘和田气象站的2部CE318自动跟踪太阳光度计于2002年6月至2003年11月期间的探测结果,结合地面气象实测资料,分析了南疆盆地大气气溶胶的光学特性。同时结合我国已有的沙尘气溶胶光学特性的研究成果,初步提出了依据气溶胶光学厚度判断沙尘天气强度的标准。结果表明:塔中、和田气溶胶光学厚度随波长的增大多呈现减小趋势,塔中个别季节有些例外;2站气溶胶光学厚度的日变化基本保持对称的抛物线形,在春、夏季尤为明显;Angstrom浑浊度系数β的拟合曲线显示β随能见度增大而减小,波长指数α随能见度的变化趋势说明弱沙尘天气下,大气中主要弥漫着小粒径的气溶胶颗粒,而强沙尘天气则以大粒径为主;沙尘气溶胶光学厚度随晴空、浮尘、扬沙、沙尘暴依次增加;沙尘天气发生时,气溶胶光学厚度的临界值基本为晴空值的两倍,沙漠地区气溶胶光学厚度≥1.1206,北京≥0.3174。而发生沙尘暴的阈值则有很大不同,沙漠区气溶胶光学厚度至少 > 3.0,北京由于大气污染等因素,其判断沙尘暴发生的阈值为1.9982。另外笔者认为AOD与水平能见度之比值能够较全面地考虑水平和垂直两个方向的要素变化,衡量沙尘天气强度更具有合理意义,值得更深一步的探讨。     

地壳中流体的大规模流动系统及其成矿意义

地壳中的水量相当于海洋体积的水量,已确定的水溶液活动深度可达２０ｋｍ,根据驱动力的不同,地壳中主要存在三大流动系统,即重力,浮力和应力驱动系统。本文评述了当前国际上有关大规模流体运移研究扩要进展和发展趋势,介绍了有关流动系统的模式和运动机制,并简要论述了其成矿意义。文章指出,目前区域古流体场地球化学背景问题已成为区域规律和热液成矿理论中一个不容回避的关键课题,地壳中大规模流动系统将成为今后地质流体研究的重要方向之一。     

基于高精度DEM和RS技术的滑坡环境指标参数快速提取方法——以陕西省宝鸡市金台区长乐塬特大型滑坡为例

DEM和RS技术是研究滑坡地质灾害的重要资料和手段。近年来,随着高空间分辨率遥感卫星和高精度雷达卫星的上天,可以获取现时性高精度的DEM,使滑坡地质灾害的研究由二维向三维提升。利用IRS-P5数据生成的5m精度的DEM,借鉴GOOGLE的三维可视性原理,将其和高空间分辨率QuickBird(0.61m)数据叠置到数字地球之上,制作成三维可视性图像,进行滑坡环境指标参数提取方法研究。研究结果表明,该方法可直接读取滑坡环境指标的三维参数,具有客观、准确、快速的特点,可为滑坡灾害评估和区域地质灾害危险性评价提供定量化资料。     

探讨建立基于Web的中国南极环境评估系统

本文根据“马德里协议”与ATCM通过的其他相关议案对南极环境管理、监测和环境影响评估的要求,在系统研究澳大利亚南极局自2003年起运行的南极环境评估系统[1]的基础上,探讨如何建立中国南极环境评估系统(Ch inese Antarctic Environm entEvaluation System,CAEES)。该系统在设计中将结合中国南极考察活动的特点、规模、发展战略以及环境保护要求,涵盖一系列静态或动态的南极环境要素数据,同时综合相关学科专家的评估意见。该系统拟采取基于W eb的数据库技术来实现南极环境的实时动态评估以及中国南极环境状况报告(Ch inese Ant-arctic Environm ental Report,CAER)的自动生成。     

1993年咸宁地震群震害损失及发震成因探讨

1993年7~8月,湖北省咸宁地区发生了一系列ML≤4.1的地震。从地震系列、地表破坏状况和地震宏观等烈度线展布特征出发,深入研究了地震与地质构造及地下水动态变化的关系,得出结论地震群可能为抽取地下水引起的构造变动而诱发。     

Trace Metals in Selected Benthic Invertebrates from Belgian Coastal Waters (1981–1996)

Mercury, cadmium, lead, copper, zinc and chromium were assessed in brown shrimp (Crangon crangon), swimming crab (Liocarcinus holsatus), hermit crab (Pagurus bernhardus), starfish (Asterias rubens) and cut trough shell (Spisula subtruncata) from ten sampling stations off the Belgian coast, including three dredge spoils disposal sites. Calculations of time trends indicated that on the whole concentrations of trace metals had significantly decreased since 1981, also on dredged material dumping sites. Starfish and hermit crab were found to be the most promising benthic indicator species for metal contamination. Globally, the location of the sites, including the dredge spoils disposal zones, showed to be of little influence on the concentrations of trace metals.     

The key indicators of transboundary water apportionment based on international laws and cases

Transboundary water, more competitive utilization and uncertain availability under the globalization trend, the issue of its apportionment which directly impacts national benefits of each riparian state is becoming one of the important topics in the world. Water is scarce in China, the most important upstream state in Asia, and this task has to be thought over in the coming future. Based on ＂International Freshwater Treaties Database＂ （1820-2007） by Oregon State University, and publications and reports on transboundary water utilization and management since 1999, 28 indicators of water apportionment adopted in 49 international treaties and cases in 1864-2002 are divided into 6 types, the spatial and temporal characteristics of the adopted indicators are analyzed in order to find the key indicator（s） of transboundary water apportionment. The major results include： the major adopted indicators, have significant differences among 5 regions/continents, the indicators at rank first and second place in the developed region （North America and Europe） according to the adopted times are ＂keeping minimum water flow＂ and ＂mean annual runoff＂, but in the developing region （Asia, Africa and South America）, the ranking order of the above two indicators is reversed; the major adopted indicators in the watersheds with insufficient water are ＂mean annual runoff＂ and ＂keeping minimum water flow＂, the ones in the watersheds with sufficient water are ＂keeping minimum water flow＂ and ＂maximum water intake＂; the international treaties signed from the first phase to the fourth phase, the developing process shows a progress of ＂fewer-increasing a lot-decreasing rapidly-equation basically＂, the regional distribution of the treaties shifts mainly from the developed region to the developing one, especially to Asia and Africa; the major adopted indicators shifts from ＂keeping minimum water flow＂ and ＂mean annual runoff＂ in 1864-1945, to ＂keeping minimum water flow＂ and ＂maximum water intake＂ in 1946-1971, then to ＂hydraulic facility operation＂ and ＂mean annual runoff＂ in 1972-1991, and finally to ＂keeping minimum water flow＂ and ＂mean annual runoff＂ in 1992-2002, the process shows similar a loop. Finally, the key indicator on transboundary water apportionment can be determined as ＂keeping minimum water flow＂.     

Overview of Ecological Restoration Technologies and Evaluation Systems

Ecological degradation is a global problem, and ecological restoration technologies have played and will continue to play an important role in its mitigation. However, the lack of systematic research and evaluations of ecological technologies has thus far affected their effective application in vulnerable ecological regions. This study therefore provides an overview of the main technologies for remediating soil and water erosion, desertification, and rock desertification in China and throughout the world. It addresses key issues and recommends approaches for evaluating ecological restoration technologies. Restoration technology emerged as early as 1800. Over the years such technology has changed from single objective applications to multi-purpose, multi-objective applications employing strategies that take into account ecosystem rehabilitation and integrated ecological and socioeconomic development. Along with this technological evolution, different countries have taken pertinent actions as part of their restoration initiatives. However, key issues remain, including the lack of location-specific restoration technologies and a methodological strategy to assess and prioritize existing technologies. This study proposes a four-level analytical hierarchical framework in conjunction with an indicator system that highlights the establishment and adaptation of associative indicators, while also recommending a three-phase evaluation method (TheMert), targeting TheMert to qualitative (quick and extensive) and quantitative (detailed) evaluations in order to select the most appropriate restoration technologies available. This study can also be used as a basis for understanding the evaluation and prioritization of restoration technologies, while increasing the awareness of decision makers and the public on the role of technology in restoring degraded ecosystems.