自然灾害对农产品市场价格影响研究——以汶川地震为例

本文构建了一个用于分析自然灾害对区域农畜产品市场价格影响的自然灾害影响农业生产的分析模型,并基于多种统计与调查资料模拟了汶川特大地震对全国农畜产品市场价格的影响。模拟表明,汶川地震对全国水稻、小麦、玉米和猪肉主要农畜产品的市场价格的变化影响甚微,没有影响全国农业生产的基准面。不过,汶川地震毋容置疑地对当地农业生产造成了...     

中国重大科技计划中人文-经济地理学研究进展

为跟踪世界科技的最新进展,解决中国快速发展过程中所面临的关键性和突出性重大问题,中国政府开展了一系列重大科技专项计划,如科技支撑计划等。气候变化、地表过程、土地利用、自然灾害是近年来人文一经济地理学者参与最广、研究最深的领域,在地表过程的人文驱动机制、资源环境承载能力评价等方面取得了重大进展和突破,为政府编制规划、开展环境外交等提供了科学依据。本文分析了上述研究计划的基本概貌,以及人文一经济地理学者在其中承担的主要任务。从个人终端消费导向的碳足迹研究、人文地理过程的系统动力学研究、土地利用重点问题咨询与决策、灾区资源环境承载能力评价等方面总结了人文一经济地理学在其中做出的主要贡献和社会影响。     

泾河流域农业旱灾风险定量评估及其空间特征

泾河流域是农业旱灾的多发地区,但是对该地农业旱灾的发生规律、旱灾影响及旱灾恢复和准备措施方面开展的研究还较少。本文根据自然灾害风险评估的理论框架,建立了1km栅格精度的泾河流域农业旱灾风险空间评估模型,并对农业旱灾致灾因子危险性及农业承险体脆弱性进行评估,最后综合评估该地区农业旱灾风险。在此基础上,分析研究区农业旱灾危险性、承险体脆弱性及风险的空间特征。本研究采用Z指数方法评估泾河流域农业旱灾致灾因子的强度,选取农作物生长季缺水率、土壤有效含水量、有效灌溉面积比以及坡度等4个指标评估研究区1km空间尺度的农业旱灾脆弱性。农业旱灾风险综合评估的结果表明,泾河流域农业旱灾风险的高风险区位于该地区北部,低风险区位于该地区南部,且不同等级风险区呈现出自东向西、自南向北逐渐降低的总体趋势,但不同等级风险区呈现间隔分布的趋势。     

CHANGES IN SOVIET NATURAL GAS FLOWS: 1970–1985*

Natural gas flows in the USSR are modeled using the out-of-kilter algorithm after the transmission system is abstracted into a network of demand and supply nodes and bounded arcs. Evaluation of the resulting flow pattern is done for 1970, 1975, 1980, and 1985. Shifts in gas supplies from the European area to Central Asia and now to West Siberia have necessitated changes in the Soviet natural gas pipeline system. The system is entering a period of long run stability between the geographic distribution of supply and demand in contrast to a continually changing distribution pattern before 1980.     

Role of carotenoids in lake sediments for reconstructing trophic history during the late Quaternary

Cultural eutrophication of lakes occurring over the last 100 years is well known. Less well known is the eutrophication of lakes in earlier, late Quaternary time due to human and other causes. The recent and earlier trophic changes are documented in the sedimentary record by several groups of parameters. Among the most revealing of these are the diverse carotenoid pigments that originate from phytoplankton, photosynthetic bacteria, and other biota. The interpretation of the carotenoids in ancient sediments is facilitated by the study of carotenoids in recent sediments from lakes with relevant limnological and historical information. I support these contentions with evidence from several Swiss lakes, with emphasis on the late Quaternary development of Pfaffikersee and Soppensee.This is the eighth of a series of papers to be published by this journal that was presented in the paleolimnology sessions organized by R. B. Davis and H. Löffler for the XIIth Congress of the International Union for Quaternary Research (INQUA), which took place in Ottawa, Canada in August 1987. Drs. Davis and Löffler are serving as guest editors of this series.     

自然系列地图轮廓界线统一协调问题

本文讨论了自然系列地图编制中的一个重要问题——自然界线之间的统一协调。作者通过对自然界线的定性、定量研究，阐述了自然界线及其相互联系的特征。并在此基础上提出了自然系列地图轮廓界线统一协调的主要方法和措施。     

Tree-Ring Analysis And Natural Hazard Chronologies: Minimum Sample Sizes And Index Values*

Tree-ring dating is employed to reconstruct chronologies of occurrence for a variety of natural hazards. The number of trees sampled varies greatly as does the minimum number of tree-ring responses. The number of trees to be sampled and an acceptable tree-ring response index should be dictated by the nature and geographical extent of the specific hazard under study. Repetitive sampling of different numbers of 30 avalanche-damaged trees showed significant differences in number of tree-ring responses over a 55-year-period. More sampling and use of a higher minimum response index allowed greater confidence in the chronology constructed from tree-rings and compared to historical records. Three geographic scales of analysis that can confound tree-ring responses are identified, and three guidelines for choosing sample size, given variations in processes, are suggested.     

豫中南天然矿泉水资源形成条件与勘查开发前景

河南省中南部处在复杂的地质、水文地质背景下。复杂的地质构造，齐全的地层岩石，强烈的新构造运动控制着天然矿泉水的形成条件。其赋存与分布除受构造体系中活动性断裂及其复合控制外，尚与地层岩性分布密切相关。天然矿泉水资源的形成机制可分为山区活动性断裂机制型和新生代断陷盆地机制型。河南省中南部天然矿泉水分布广泛、类型较全、资源丰富、水质优良，具有广阔的勘查与开发利用前景。     

小视场CCD图像的几何定标

针对长焦距望远镜CCD观测天然卫星的情况,导出了用两颗亮星作为定标时,CCD视场几何参数(比例尺和指向)测量的误差公式,进而设计了多定标星定标时正确的归算方案。新方案不仅对天然卫星的位置测量,也对同类型的小视场CCD位置测量具有指导意义。