时域反射技术在地学研究中的应用

综合介绍了时域反射技术在地学研究中的应用。包括时域反射仪的工作原理、测量参数(特征阻抗、介电常数、土壤含水量、土壤电导率)、时域反射探针技术以及时域反射技术在农业地质、水文地质、灾害地质等研究中的应用与进展。     

The Production of Methanol by Flowering Plants and the Global Cycle of Methanol

Methanol has been recognised as an important constituent of the background atmosphere, but little is known about its overall cycle in the biosphere/atmosphere system. A model is proposed for the production and emission to the atmosphere of methanol by flowering plants based on plant structure and metabolic properties, particularly the demethylation of pectin in the primary cell walls. This model provides a framework to extend seven sets of measurements of methanol emission rates to the global terrestrial biosphere. A global rate of release of methanol from plants to the atmosphere of 100 Tg y^–1 is calculated. A separate model of the global cycle of methanol is constructed involving emissions from plant growth and decay, atmospheric and oceanic chemical production, biomass burning and industrial production. Removal processes occur through hydroxyl radical attack in the atmosphere, in clouds and oceans, and wet and dry deposition. The model successfully reproduces the methanol concentrations in the continental boundary-layer and the free atmosphere, including the inter-hemispheric gradient in the free atmosphere. The model demonstrates a new concept in global biogeochemistry, the coupling of plant cell growth with the global atmospheric concentration of methanol. The model indicates that the ocean provides a storage reservoir capable of holding at least 66 times more methanol than the atmosphere. The ocean surface layer reservoir essentially buffers the atmospheric concentration of methanol, providing a physically based smoothing mechanism with a time constant of the order of one year.     

浅议学科交叉与地球系统科学

以整体系统的观念认识地球 ,强化学科间的交叉与渗透 ,是 2 1世纪初地球科学发展的主题。各国都十分重视推动学科交叉研究 ,并将学科交叉分为Modidisciplinary、Interdisciplinary、Transdiscipli nary三个层次。地球系统科学的两大前沿为“地球系统的联系”和“地球系统的演化” ,2 1世纪地球科学的突破在于地球系统变化理论的形成。笔者指出 :目前 ,我们的观念还跟不上地球科学的发展 ,尤其是“学科交叉”的理念不强 ,缺乏地球系统科学的思维 ,但我们有开展地球系统科学研究的有利条件     

Changes in the mode of Southern Ocean circulation over the last glacial cycle revealed by foraminiferal stable isotopic variability

Benthic foraminiferal oxygen and carbon isotopic records from Southern Ocean sediment cores show that during the last glacial period, the South Atlantic sector of the deep Southern Ocean filled to roughly 2500 m with water uniformly low in δ¹³C, resulting in the appearance of a strong mid-depth nutricline similar to those observed in glacial northern oceans. Concomitantly, deep water isotopic gradients developed between the Pacific and Atlantic sectors of the Southern Ocean; the δ¹³C of benthic foraminifera in Pacific sediments remained significantly higher than those in the Atlantic during the glacial episode. These two observations help to define the extent of what has become known as the ‘Southern Ocean low δ¹³C problem’. One explanation for this glacial distribution of δ¹³C calls upon surface productivity overprints or changes in the microhabitat of benthic foraminifera to lower glacial age δ¹³C values. We show here, however, that glacial-interglacial δ¹³C shifts are similarly large everywhere in the deep South Atlantic, regardless of productivity regime or sedimentary environment. Furthermore, the degree of isotopic decoupling between the Atlantic and Pacific basins is proportional to the magnitude of δ¹³C change in the Atlantic on all time scales. Thus, we conclude that the profoundly altered distribution of δ¹³C in the glacial Southern Ocean is most likely the result of deep ocean circulation changes. While the characteristics of the Southern Ocean δ¹³C records clearly point to reduced North Atlantic Deep Water input during glacial periods, the basinal differences suggest that the mode of Southern Ocean deep water formation must have been altered as well.     

软科学与决策咨询研究

文章比较系统地分析了软科学的概念，提出了软科学研究现象，对探讨了软科学与决策咨询的关系，论述了决策咨询研究的现实意义，认为软科学是决策咨询的学科基础，软科学研究走向市场是大势所趋，而决策咨询是软科学研究成果市场化的基本形式，大力发展咨询产业是我国社会主义市场经济建设的重要组成部分。     

依靠科技进步加快经济发展

河南省煤田地质局经济的持续快速发展,得益于不断推进科技进步。表现为着力巩固发展地勘优势,使核心技术得到不断升级和创新,形成强势竞争力。科技进步的核心问题是人。尊重人才的关键是改革用人机制,用事业留人,用待遇留人,用感情留人。     

内蒙古达茂旗北部奥陶纪花岗岩类特征及其构造意义

研究区奥陶纪花岗岩分布于乌兰布拉格 -哥舍深大断裂 (槽台断裂 )以北 ,岩石类型主要有闪长岩、石英闪长岩、斜长花岗岩和花岗闪长岩。岩石中 Si O2 质量分数为 5 6.76%～ 69.2 4 % ,Al2 O3较高 (多 >1 6% ) ,富 Na2 O贫 K2 O,A/ CNK均 <1 .1 ,为准铝质的钙碱性岩石系列。稀土总量普遍较低 ,为 (63 .4 1～ 1 4 0 .61 )× 1 0 - 6 ,轻重稀土分馏强烈 ,铕异常不明显 (δEu=0 .95～1 .2 2 6)。痕量元素特征与典型的火山弧花岗岩相似。结合区域地质背景 ,认为该套花岗岩类为与洋壳消减有关的岛弧型花岗岩 ,岩浆起源于加厚陆壳的底部。从花岗岩的分布及迁移规律推测 ,华北陆块与其北缘增生带之间的早古生代洋壳可能是由南西向北东的斜向消减     

大洋多金属结核研究概况

从多金属结核的分布及富集规律、物质成分、内部结构、形成机制等方面论述了目前国内外的一些研究动态,对目前在这一研究领域提出的一些新概念、新方法作了一定的介绍.在分析和总结前人研究成果的基础上,指出了在这一研究领域还存在的一些问题及今后研究的方向.     

拓展国际合作的视野--出席第23届IUGG大会有感

第23届IUGG大会一个突出的特点就是学科间的交叉和融合，充分反映了新世纪地球科学以实现全球变化的预测为目标，进行多学科综合研究的发展趋势。文章从IUGG内部跨学科的合作研究，IUGG与国际科联(ICSU)各专业委员会之间的合作交流，以及IUGG与政府间组织和其他国际机构的合作三个层面，简要介绍了IUGG在全球范围内开展国际合作研究的概况。在此基础上，结合我国的实际，就拓展国际合作领域，提高我国地球科学研究水平，扩大我国的国际影响等提出了相应的建议。     

分形学:现代地图学的非线性数学分析方法

分析了地图学的传统数学分析方法，讨论了对象复杂性与方法简单化的矛盾，阐述了分形几何学，为现代地图学研究的定量化、系统化提供了新的数学分析方法。