美国墨西哥湾岸地区石油生产综合体的形成

墨西哥湾岸是美国石油工业的核心地区。本文分析了本地区在有利的区域条件和社会、经济、技术发展要求的共同作用下,石油生产地域综合体的形成过程。分析中强调了主导部门在区域经济开发和区域经济地理研究中的意义。     

THE POLITICAL ECONOMY OF FOREST POLICY IN MEXICO AND CHILE

Widespread agreement exists on the broad outlines of the concept of sustainable development for developing countries. This calls for a development model capable of meeting basic needs without depleting natural resources at a rate that robs future generations of their use. In this regard, citizen participation is also considered key to legitimise such policy choices. However, there is considerable disagreement over the substance and meaning of the major components of the concept and the relationship between them. This paper argues that positions in policy disputes over the sustainable development of the forest cluster in two distinct approaches: market‐friendly initiatives and grassroots development. Since market economies prevail almost everywhere, the question that is posed concerns the conditions under which the grassroots development approach is included as a significant complement to market‐friendly initiatives. This is a political question, requiring an examination of actors, interests and power resources. The paper thus applies a political economy framework to a paired comparison of Mexico, where grassroots development approaches (community forestry) had notable successes, and Chile, where market‐friendly forest policy crowded out alternatives.     

A JÖKULHLAUP FROM A LAURENTIAN CAPTURED ICE SHELF TO THE GULF OF MEXICO COULD HAVE CAUSED THE BØLLING WARMING

Since the rapid rate of global warming at the onset of the Bølling interstadial became evident, its cause has been under debate. It coincides closely in time with a strong global transgression called meltwater pulse 1a. One attempt at solution says that a meltwater pulse of Antarctic origin could cause an increase in North Atlantic Deep Water formation, and thus give rise to the Bølling interstadial. However, others have disputed that Antarctic meltwater would have that effect, and furthermore, the start of the Bølling interstadial is not even associated with an increase in North Atlantic Deep Water. A controversial hypothesis says that some Laurentian meltwater came from a jökulhlaup (sub-glacial outburst flood), but no study has yet shown unequivocally that sufficient amounts of water could be stored under the ice. Furthermore, according to all available data a melt-water pulse from the Laurentian ice would give rise to strong cooling, not warming. Nevertheless, meg-afloods appear instrumental in accumulating the Mississippi Fan, created entirely during the Quaternary period, and dramatic climate changes are characteristic of this period. This paper presents a hypothetical chain of events, building on the published literature and simple calculations, to investigate whether the order of magnitude is reasonable. The hypothesis is that a jökulhlaup from a Laurentian captured ice shelf flowed out through the Mississippi, boosted the Gulf Stream, reinvigorated the North Atlantic circulation, and as a result triggered the Bølling warm phase.     

浙江瓯江口南岸潮滩相带的时空变化

瓯江口南岸潮滩可分为三个沉积地貌相带：高潮滩物质由砂、泥混合沉积组成，沿岸沙堤增长；中潮滩物质以砂质为主，坑、洼地貌遍布，滩脊发育，是潮滩中最活跃，对水动力条件反映最敏感的相带；低潮滩物质由泥质组成，滩面平缓，是稳定的淤积带。潮滩相带的沉积物、地貌特征具有明显的时空变化，瓯江入海的水沙对瓯江口南岸潮滩演变产生明显的影响。     

长江口浑浊带含沙量的潮流变化及其成因分析

实测数据显示在长江口南槽浑浊带内,近河床含沙量在很多情况下在转流后1—3h内出现峰值,在涨、落急流速最大时含沙量却迅速下降。本文利用实测数据计算了不问潮时的泥沙垂向紊动扩散系数,发现它与底层含沙量有类似的变化过程,结合近底层高浓度悬沙的迁移,认为转流后出现的含沙量峰值主要是由于憩流期沉降到河床的悬沙重新悬浮引起的。重新悬浮是浑浊带的重要成因。     

泥石流运动流型与流态特征

泥石流的运动流型与流态是研究泥石流运动力学的重要内容。以云南东川蒋家沟泥石流运动观测为例,对阵流型、连续型、复合型三种流型及相应的流量过程特征进行了分析;借鉴水力学的流态理论,对天然沟遭中泥石流的流动状态(即层动流、波动流现象)进行了探讨分析,指出在一阵流动过程中也会出现几种不同流态特征。     

云南蒋家沟泥石流运动要素观测数据整编

根据中国科学院东川泥石流观测研究站所在地蒋家沟的多年观测数据,利用成熟的计算和分析方法,按建立数据库的要求对泥石流运动要素的原始观测数据进行了计算机处理,提出了建立泥石流运动要素数据库的内容及其指标和计算公式,并对数据库的编建原则、特点及结果表达进行了讨论。     

未来长江口流量和潮位变化及其对河口水质的影响

本文通过长江口实测氯度与流量和潮位资料的相关分析,预估了未来河口水质的变化。计算表明,当大通站下泄流量不足13×10³m³/s时,未来东线调水及海平面上升,将使长江口南支河段水质严重恶化;三峡水库建成后,枯季1-3月增加下泄水量虽可抵消东线调水的影响,但在水库蓄水的10月遇枯水年分,水质将大幅度下降。     

辽东潮间浅滩的综合特征

辽东潮间浅滩是我国淤泥质海岸的重要组成部分。因位处海陆结合部,承受海水周期性浸淹,故兼有海洋与陆地的物理、化学和生物学等共同特征。因此,潮间浅滩是一个特定的生态系统,构成完整的自然综合体。     

MUEBLES RÚSTICOS IN MEXICO AND THE UNITED STATES

ABSTRACT. Sales of muebles rústicos, or rustic wooden furniture made in Mexico, have grown rapidly in the United States since 1994. Analysis of the recent rise of the industry tracks manufacturing and marketing methods in major production areas of Mexico. Consumer taste for “authentic” handmade goods of simple design and the vogue of the “Santa Fe” style across the American Southwest mesh with Mexican producers' need to seek foreign markets during an economic crisis. Changing style preferences, along with the furniture's handcrafted appearance, its competitive cost, and the makers' flexible production methods, are reasons for the increased popularity of this folk commodity.     

RAISED MARINE TERRACES ALONG THE GULF OF ADEN COAST OF SOMALIA

Mapping in the Galweda-Elayu area of northern Somalia has revealed depositional and erosional marine terraces at elevations of approximately 16 m, 8 m, and 2 m. These terraces vary from 0–2300 m, 200–2200 m, and 0–800 m in width, respectively. Sediments exposed in stream-valley walls demonstrate that the two higher terraces were formed by marine transgressions followed later by regressions to below present sea level. Beach ridges on the terraced alluvial fan at the mouth of togga Galweda imply that sea level and/or land elevation varied by at least 6 m during the formation of the 16-m terrace and by at least 3 m during the formation of the 8-m terrace. ²³⁰Th/²³⁴U ages of corals suggest that the 8-m terrace was formed during deep-sea isotope substage 5c (105 kyr B.P.) and the 2-m terrace during substage 5a (80 kyr B.P.). A 7-kyr-old coral from above the present storm beach on the outer flanks of the 2-m terrace suggests that sea level in the Gulf of Aden was close to its present level by the middle Holocene. No material suitable for dating was recovered from the 16-m terrace, but on morphological grounds and based on marine-terrace elevations elsewhere in the Red Sea-Gulf of Aden rift zone, we believe that the 16-m terrace was formed during isotope substage 5e (132–120 kyr B.P.), when global sea level was about 6 m above present.     

潮汐盐沼环境特点及高分辨率海面变化有孔虫标尺

潮汐盐沼是海洋边缘海环境的最边缘部分,是海陆过渡的真正边界。盐沼环境因素具明显的垂直分带性,各环境参数变化是典型的海洋或陆地不可相比的,盐沼坡度平缓,由海向陆的环境变化在这里分异清楚;沉积中垂向变化平面上得到极大的放大等。据国外研究,盐沼环境控制着有孔虫的特征和分布,利于盐沼有孔虫的垂直分带恢复古海平面变化,精确到±２０ｃｍ,甚至±５ｃｍ,这在海面变化、环境演变、全球变化研究上有重要意义。     

长江河口北槽非均匀泥沙起动分析

20世纪80年代后期以来,长江河口的北槽被开辟为上海港的入海通道,深水航道工程也在此修建,现在长江口的深水航道工程一期工程已经结束,一期工程后的航道治理的效果如何,其主要指标之一是看航道泥沙的落淤的程度,泥沙回淤港池的动力条件很复杂,而多种动力条件引起的泥沙起动也是判断河槽冲淤的重要特性之一.利用一期工程结束后2003年长江河口北槽枯季调查的资料和窦国仁、张瑞瑾、唐存本的泥沙起动公式,计算长江河口北槽的泥沙起动流速,并对结果和实测值进行了对比,得到深水航道所在的北槽底部泥沙的流速远大于该地泥沙的起动流速,故河槽将进一步加深,向更有利的方向发展.     

苏北岸外辐射沙洲王港西洋潮流通道稳定性研究*

在粉砂淤泥海岸,利用潮流通道建港,稳定性是一个首要问题。该文首先分析了西洋潮流通道的环境背景,然后根据实测资料,利用多种方法,包括地理息信系统、遥感研究、沉积物粒度、矿物、微体及水文泥沙资料分析等对西洋的稳定性作了综合研究,认为,西洋通道特别是其西水道是一条稳定性好的潮流通道。     

THE TIDAL FLATS MORPHOLOGICAL DEVELOPMENT AND THE COASTAL UND RECMMATION IN SHANGHAI

1.IntroductionShanghaiisloeatedonthesouthbankofChanaiiangEstuarywithHangzhouBayinitss0uthandEaStChinaSeainitseast.ThetotallotofcoastallineandrivershorelinearoundShanghaiis449.7kn.Wthitsabundantwat6rdischarge,largequantityofswhmatsarecarnedanddrpositedinChanaiiangEStuaryundertheinteractionofmanneandnorunanneprocesseswhichformedvastexPansesofhdalflatsontheestuaryanditSadjaodbay(Li,l990)(Figurel).ll.DynedcFact0r0fTidalflats1.Waterandscdlinentc0ndih0nWatrdi,chargeatDatongStationis9.26xl0"…