Understanding El Niño — The importance of Grey Literature in Coastal Ecosystem Research and Management     

Sven Thatje  Jürgen Laudien  Olaf Heilmayer  Cornelia E. Nauen 《Marine Policy》2007

Access to information about past states of the environment and social systems is fundamental to understand, and cope with, the challenges of climate change and over-exploitation of natural resources at the onset of the 21st century. The loss of (old) data is a major threat to understanding better and mitigating long-term effects of human activities and anthropogenic changes to the environment. Although this is intuitively evident for old and local literature of any kind, even present-day international publishing of papers without the underlying raw data makes access to basic information a crucial issue. Here, we summarise experience resulting from a EU-funded International Science & Technology Cooperation (INCO) project (CENSOR) addressing Coastal Ecosystem Research and Management in the El Niño Southern Oscillation (ENSO) context. We show that indeed “Grey Literature” is still one of the most important sources of knowledge about natural science research and management of natural resource systems in Latin American countries. We argue that public archiving of original data of present-day research and old (Grey) Literature and easy public access are important for appreciating today's global environmental challenges caused by human activities, both past and present.  相似文献   

关中地区的新石器古文化发展与古环境变化的关系   总被引：11，自引：2，他引：9       下载免费PDF全文

吕厚远  张健平 《第四纪研究》2008,28(6):1050-1060

气候环境变化作为影响或制约古文化发展、演化的重要因素,虽然经常受到质疑,但依然被越来越多的考古工作者,包括一些古气候学者所接受。关中地区是我国古代文明重要的发源地之一,为探讨气候环境变化与古文化演化之间可能存在的联系提供了条件。本文对已有很好研究基础的渭南全新世黄土剖面的孢粉、植硅体、蜗牛化石及磁化率和粒度记录进行综合分析,研究得出该区全新世以来有3次突出的气候温暖湿润期（9000～7300aB.P.,6800～5500aB.P.和4500～4300aB.P.）和3次明显而短暂的寒冷干旱期（7300～6800aB.P.,5500～5000aB.P.和约4000aB.P.）。温暖湿润气候期与关中地区的老官台（8000～7000aB.P.）、仰韶（7000～5000aB.P.）、龙山（5000～4000aB.P.）等文化繁盛期几乎是同步的,而发生在7300～6800aB.P.,5500～5000aB.P.及4000aB.P.前后的寒冷干旱气候环境,不是简单的气候冷暖变化,而是影响了生物、水、大气等表生地球系统的气候变化事件,改变了该区的植被类型和生物群落的变迁,这3次气候变化事件时间上大致对应了老官台-仰韶-龙山-夏商文化交替的时间。然而,根据目前的气候记录及时间分辨率还难以判断更次一级的气候环境变化与各文化期不同文化类型变化之间的关系。对关中地区泉护遗址植硅体的分析显示,4500aB.P.以来水稻含量的增加与气候变干的趋势并不一致,推测可能与古人利用渭河水资源种植水稻有关。研究认为关中地区气候环境变化与文化发展之间的关系,有一定的规律可寻,但是由于目前对古气候-古环境变化的幅度、详细的考古文化性质的认识不足,以及时间分辨率和年代学的限制,还无法确切说明什么程度的气候环境变化对哪些文化类型通过什么机制产生了何种程度的影响。  相似文献   

基于神经网络方法的芦苇叶面积指数遥感反演   总被引：2，自引：0，他引：2  

陈健  倪绍祥  李云梅 《国土资源遥感》2008,(2):62-67

提出了一种从TM图像上获取芦苇冠层叶面积指数的方法:首先对芦苇的生长背景进行分类;然后,对不同的背景光谱利用冠层反射率(FCR)模型计算得到查找表;最后,利用实测数据和查找表中的数据作为参数进行BP神经网络模型训练,从而得到芦苇冠层LAI。结果表明,人工神经网络方法有很强的非线性拟合能力,能够消除背景对反演结果的影响,有效提高LAI反演的精度。  相似文献   

三峡库区高切坡致灾因素及防护对策——以重庆市万州区为例   总被引：1，自引：0，他引：1  

祝介旺  和海芳  柏松  伍法权 《中国地质灾害与防治学报》2008,19(2):7-11

三峡库区百万移民的搬迁建设导致大量高切坡的形成。未及时治理或治理不当的高切坡,不同程度地发生破坏,影响了人们的正常生活,甚至引发了地质灾害。因此,科学认识及治理高切坡十分必要。重庆市万州区高切坡主要有风化及差异风化、崩塌和土体滑塌等破坏形式。影响破坏的因素主要为工程地质条件、气候及时间效应。针对高切坡不同的破坏形式,以安全、经济及环境和谐的人文理念作为设计指导思想,充分论证了高切坡的防护方案,即：削坡、排水以及格构防护较适合万州区高切坡的防护。这些措施,既能很好地解决高切坡的防护问题,又能兼顾环保、降低造价。研究结果可以作为三峡地区高切坡类地质灾害防护设计的参考。也可为其它流域类似问题借鉴。  相似文献   

三峡水库区兴山后坝滑坡成因分析   总被引：2，自引：0，他引：2  

艾飞  侯天顺  关国杰 《中国地质灾害与防治学报》2008,19(3):1-5

文章通过对三峡水库区兴山后坝滑坡的地质、结构及变形特征研究以及稳定性分析,阐明了该滑坡成因和影响因素。研究发现,滑坡活动主要受地形地貌、地层岩性、人类工程活动以及降雨等因素的影响。运用剩余推力法对比分析天然及暴雨条件下不同层位的滑坡稳定性系数,得出在暴雨作用下滑坡表层滑带稳定性系数最小,不同滑带的稳定性受降雨的影响也各不相同,呈表层〉浅层〉深层的规律;这主要受滑带土的粘土矿物组分的影响。  相似文献   

钢筋混凝土桩网复合地基沉降计算方法优选     

黄国林 《云南地质》2008,27(1):97-101

钢筋混凝土桩网复合地基是一种新的地基处理技术。本文对适用于钢筋混凝土桩网复合地基沉降计算的方法进行探讨。  相似文献   

三峡库区地质灾害易损性模糊综合评价   总被引：3，自引：1，他引：2  

胡焕校  张立明 《地质灾害与环境保护》2008,19(2):57-61

地质灾害是灾害危险性对承灾体易损性综合作用的结果,减灾应从减少地质灾害的发生频率和降低其易损性入手,限于目前的科学水平,人们难以改变地质灾害的发生过程,那么降低地质灾害易损性就成为减灾的重要措施,因此进行灾害易损性评价就显得尤为重要。本文以三峡库区为研究区,选取人口密度、国内生产总值密度等指标,运用模糊综合评判对其进行了定量评估。由于各指标因子在地质灾害易损性中的作用具有模糊性,因此运用模糊模型进行评价具有一定的意义。将库区地质灾害易损性程度划分为4个等级,研究结果表明,三峡库区地质灾害易损性程度总体较高。易损度较高的地区应强化减灾意识、调整人口结构以及加大防灾投入,以降低本地区的地质灾害易损性。  相似文献   

REE Abundance and REE Minerals in Granitic Rocks in the Nanling Range,Jiangxi Province,Southern China,and Generation of the REE‐rich Weathered Crust Deposits     

Shunso Ishihara  Renmin Hua  Mihoko Hoshino  Hiroyasu Murakami 《Resource Geology》2008,58(4):355-372

Studies of Mesozoic granites associated with rare earth element (REE)‐rich weathered crust deposits in southernmost Jiangxi Province indicate that they have high‐K to shoshonite compositions and belong to ilmenite‐series I‐type granites. Of the studied rocks at 59–292 ppm of bulk REE content, the highest are seen in the biotite granites of Dingnan (358, 429 ppm) and mafic biotite granite of the Wuliting Granite (344 ppm) near the Dajishan tungsten mine, both areas where weathered‐crust REE deposits occur. REE‐bearing accessory minerals in these granites are mainly zircon, apatite and allanite, and REE‐fluorocarbonates are common. REE enrichment occurs in the rims of apatite crystals, and in fluorocarbonates that occur along grain boundaries of and cracks in major silicate minerals, and in fluorocarbonates that replaced altered biotite. It is therefore thought that a major part of the REE content of these granites was concentrated during deuteric activity, rather than during magmatic crystallization. The crack‐filling REE‐fluorocarbonates could subsequently have been easily leached out and deposited in weathered crust developed during a long period of exposure.  相似文献   

Late Paleozoic volcanism in the central part of the Southern Permian Basin (NE Germany, W Poland): facies distribution and volcano-topographic hiati     

Marion Geißler  Christoph Breitkreuz  Hubert Kiersnowski 《International Journal of Earth Sciences》2008,97(5):973-989

  相似文献   

An implementation of rock engineering system for ranking the instability potential of natural slopes in Greek territory. An application in Karditsa County   总被引：1，自引：0，他引：1  

D. Rozos  L. Pyrgiotis  S. Skias  P. Tsagaratos 《Landslides》2008,5(3):261-270

This paper presents an application of rock engineering system (RES) in an attempt to reveal and assess the inherent instability potential of 388 sites where equivalent landslides have been manifested and recorded in the region of Karditsa County, Greece. The main objective has been defining the principal causative and triggering factors responsible for the manifestation of landslide phenomena, quantify their interactions, obtain their weighted coefficients, and calculate the instability index, which refers to the inherent potential instability of each natural slope of the examined region. From the statistical interpretation of the data reported in a well-documented database and concerning the examined failure sites, a clear correlation between the instability index and the area affected by a single landslide event has been revealed. Almost the entire failure sites, 98% of the examined slope sites, exhibit an instability index value over 55, a value which is thought to be a critical threshold for landslide manifestation concerning natural slopes in Karditsa County. It is argued that the presented RES methodology, engaging the selected set of parameters, could be considered as an effective expert's tool for ranking, in an objectively optimal and simple way, the instability potential of natural slopes in Karditsa County, and thus providing a tool for sound zoning landslide hazard.  相似文献