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第四纪研究 , 2009,
Abstract:
我国东北地区晚更新世中晚期环境变化与猛犸象—披毛犀动物群绝灭研究综述

地球科学进展 , 2009,
Abstract: 通过对文献资料的总结、统计分析,结合对我国东北地区的实地考察和初步研究结果,论述了我国东北地区晚更新世中晚期以来环境变化与猛犸象—披毛犀动物群演化、灭绝的研究现状和存在问题及其与国际对相应时段猛犸象研究之间的差距。提出加强对我国东北地区晚更新世气候环境的重建、认识气候变化的区域特点和突变性,系统而可靠地建立以猛犸象—披毛犀为主的化石动物年代序列、区分主要类型化石动物年代是研究的关键。以独立的气候环境变化和化石动物的年代序列为参照系,在区域环境变化的框架内讨论化石动物群生存的气候环境、生态特征和灭绝过程,进而探讨动物群演化及灭绝与气候环境变化的关系。这将为认识区域环境突变、动植物对环境变化的响应、我国东北地区晚更新世猛犸象—披毛犀动物群与欧亚大陆其它地区猛犸象之间的内在联系,认识人类演化与生存环境的适应、动植物演替与绝灭的临界条件等一系列重大科学问题提供资料。
撒哈拉沙漠东北部苏丹境内东西断面粒度分布特征及其成因与环境

中国沙漠 , 1996,
Abstract: 对撒哈拉沙漠东北部苏丹境内东西方向36个样品粒度分析结果表明:其粒度组成可分为10种不同的类型;粒度参数具以下特征值:MZ=1.34~2.43;标准偏差δI=0.51~1.43;偏度SKI有正有负,变化于-0.3~0.47;峰态KG=0.66~1.04。同时显示,绝大多数样品的频率曲线为多峰态,具有典型河流沙的粒度特征;不同样品及粒度分布形式在地域上无明显规律性。分析结果说明非洲撒哈拉沙漠东北部沙漠砂的形成与河流作用有关。
撒哈拉沙漠东北部全新世气候环境与人类活动

中国沙漠 , 1997,
Abstract: 现代极端干旱的撒哈拉沙漠东北部,在12000aB.P.前出现了代表湿润气候记录的湖相沉积;全新世以来,在9900~2400aB.P.形成了大面积的连续湖泊,并在9800~6450aB.P.达到鼎盛时期。在6000aB.P.~3600aB.P.前,湖泊演化进入波动期,反映了该时期气候环境周期性的变动并具600年的准周期。撒哈拉沙漠东北全新世湿润时期,是该区古人类发展与进步、繁演与分化的时期;也是自然演变史上一个十分重要的时期,其中强烈的风化作用和碎屑物质积累为今日撒哈拉沙漠的形成奠定了物质基础。
基于cad/cae技术的水电站进水塔设计
,
人民黄河 , 2012,
Abstract: ?基于现代设计方法的思想,对水工建筑物的现代设计方法进行探索,通过cad三维软件的参数化功能进行结构设计,将建立的模型导入cae软件进行求解及后处理.整个过程为软件间无缝集成,实现了cad、cae之间的有效结合,可将cae分析结果快速反馈于cad设计,对初步设计不合理的地方能够便捷地进行修改,为大型水利水电工程节省设计周期.
金沙江干热河谷地理环境演化研究进展与问题
Progress and Issues on Geographical Environment Evolution in Dry-Hot Valley of Jinsha River
 [PDF]

自强, 明庆忠, , 李华勇, 段立曾
Geographical Science Research (GSER) , 2013, DOI: 10.12677/GSER.2013.21001
Abstract:
金沙江干热河谷是一种分布在金沙江流域的特殊地理景观,这些地区的生态环境与周围地区有巨大差异,形成一种局部的干旱生境。由于特殊的干、热气候条件使得这些地区的生态环境恶劣,生态系统脆弱,严重地制约了这些地区的生态保护和社会发展。本文主要对近几十年来众多学者对金沙江干热河谷的生态环境特点、植被、水土及演化原因的研究进行了回顾,认为现阶段研究主要存在以下问题:干热河谷的界定不清;干热河谷形成原因及过程研究不明;人地关系研究不足;整体、系统的研究较少。有鉴于上述问题,我们提出了未来研究应予重视或优先研究的方向:重视干热河谷的界定研究;加强干热河谷形成原因和过程的研究;开展人地关系的深层次研究;深入干热河谷对全球变化响应的研究;开展整体、系统的研究。
Dry-hot valley of Jinsha River is a special geographical landscape distribute in Jinsha River drainage area. Those areas are brush-fire arid environment and their ecological environment have very huge difference with the surrounding areas. Due to the special dry and hot climate, the ecological environment are harsh and fragile, and restrict those areas’ ecological protection and social development. This article primarily reviewed the studies of recent decades from the aspects of the natural environment characteristics, the vege-tation, the water and soil and the cause of environment evolution in dry-hot valley of Jinsha River. The au-thors think that the studies at present stage have the following problems. The differentiation of dry-hot valley is not clear; the still confusing; lack of environment and human-nature relationship research; the integral and systematic researches are few. For the problems, we present several aspects that should be pay attention and give priority to consider in the future. Attach importance to the differentiation of dry-hot valley; strengthen the research of cause and process of evolution; do more deep level human-nature relationship and the response of dry-hot valley to global change researches; do some integral and systematic researches.
金沙江堵江堰塞事件及其地貌环境效应研究进展
Research Progress of Landslide Dam Events of Jinsha River and Its Geomorphologic and Environmental Effects
 [PDF]

段立曾, 明庆忠, , 李华勇, 自强
Advances in Geosciences (AG) , 2013, DOI: 10.12677/AG.2013.31002
Abstract:
强烈的新构造运动和区域地质地貌条件使得堵江堰塞事件在金沙江河谷广泛发育,通过总结前人研究与笔者野外考察和分析研究后认为,堵江堰塞事件发育对金沙江河谷演化的作用与影响大致为以下次序:构造活动及气候异常事件发生滑坡堵江事件形成堰塞坝()堰塞坝()解体消亡河谷地貌及环境变化现代金沙江河谷地貌的形成。同时,堵江堰塞现象有在地质构造破碎带、河谷纵比降变化、构造运动活跃和异常气候事件高发期高频发育之规律和具有突发性、短暂性等显著特点堵江堰塞造成区域沉积过程和河流下切动力过程的快速改变以及水文、局域气候、地质稳定性、河谷地貌和生态环境的快速变化。堵江堰塞事件在各河段的发生形式、发育年代和机制、期次及次生地貌环境效应表现各异,加上后期侵蚀及堵江过程对于前期遗迹的破坏作用使得其研究变得十分复杂而困难。因此,在其系统研究、年代的确定、堰塞坝()的识别、堰塞湖钻探采样及其沉积物信息提取研究等方面还有更大的深入探讨和提升空间。
Strong neotectonic movements and regional landscape conditions results in landslide damming events are widely exist in JinshaRivervalley. Through summarizing the study results by other researchers and the our field invest- tigations, the development processes of the landslide damming of Jinsha River and its effects on the evolution of land- scape can be described as following sequences: strong neotectonic activities and climatic anomaly events → the occur- rence of landslide blocking river → landslide dam (dammed lakes) formation → landslide dam (dammed lakes) bro- ken/collapse → river re-shaping the valley
生态文明视野下云南高原湖滨生态城镇群的构建及其可行性探析
Explore and Analysis about the Construction of Eco-Cities in the Catchment of Plateau Lakes and It’s Feasibility in Yunnan Province under the View of Ecological Civilization
 [PDF]

段立曾, , 明庆忠, 李华勇, 自强
Sustainable Development (SD) , 2013, DOI: 10.12677/SD.2013.32006
Abstract: 随着明代汉族的移民、明清以来工商业的发展和19世纪后期开始的城市人口集聚增加直到现代经济社会的快速发展,云南省城镇化水平、城镇人口和用地上升到一个前所未有的高度。随之带来的是包括昆明及各地州城市因城镇扩张和区域生态环境不协调的城市病,严重制约云南省未来的可持续发展。高原湖滨生态城镇群的构建是缓解这一矛盾的重要决策之一,其以低碳经济、西部大开发中国面向西南开放的重要桥头堡城镇上山等为背景;以云南省湖泊众多、水系发达和区域开发潜力等为优势,高原湖滨生态城镇群的构建将在区域产业结构和经济发展、区域生态环境改善和生态文化提升方面具有重要的战略和现实意义。其中,田园城镇发展模式、生态功能核心区和产业集聚小区是其核心内容,但也面临着区域构造活动强烈、自然灾害频发和湖泊污染等挑战
The immigration of ethnic Han in the Ming Dynasty, the development of manufacturing and commerce since the Ming-Qing period, the intensification of populational congregation since the late 19th century, and the rapid growth of modern economy have all contributed to the unprecedented high levels of urbanization, urban population, and land use in Yunnan Province. Such a situation leads to the most of cities, including Kunming have the “city disease”, that referring to the unlimited urban expansion and uneven development of the regional ecological environment, which seriously endanger the sustainable development of Yunnan province. The construction of plateau lake eco-cities is one of the functional suggestions to alleviate this contradiction, which based on the policies of
洱海生态环境研究现状及存在问题
The Research Status and Problems on Ecology and Environment of Lake Erhai
 [PDF]

蔡燕凤, , 陈光杰, 段立曾, 自强, 王熊飞, 李华勇
Advances in Geosciences (AG) , 2013, DOI: 10.12677/AG.2013.34034
Abstract:
近年来,随着洱海生态环境的日益恶化和流域大面积快速开发,洱海的生态环境问题引起了国内外学者的广泛关注。本文对上世纪50年代以来在洱海所做的研究工作进行分析、总结,对洱海环境(包括洱海富营养化、重金属污染、流域开发和植被状况)、生态(包括生物多样性、食物链变化、生态系统特征变化)方面的研究现状进行了分析,结合所得数据进一步分析了气象因素(气温、降水与风速)与水质变化的关系,指出洱海及流域研究中还存在许多问题与不足(如蓝藻爆发历史、对浮游动物和食物链的详细研究、区分多重压力对洱海富营养化的驱动强度)。以期对洱海生态、环境的情况有一个综合了解,为以后在洱海继续开展相关科研工作提供一定的认知基础,更好地为洱海的生态修复工作提供建设性意见。
There are wide concerns from scholars at domestic and overseas on the ecological environment of Lake Erhai recently as a consequence of worsening status, massive and rapid development on the catchment of Lake Erhai. This paper summarizes the research status of Lake Erhai which has been collected since 1950s, analyzes the current situation of the environment (including eutrophication, heavy metal pollution, and catchment development and vegetation status) and ecology (including biological diversity, food web change, and characteristics changes of ecological system), and makes a further analysis on the meteorological factors (including temperature, precipitation and wind speed). Through those data we point out that there are some problems still exist in the research of Lake Erhai, for instance, the Cyano- phyta explosion history, the detailed research on zoo-plankton and food chain, the distinction of drive strength of multi- ple pressure on the process of eutrophication of Lake Erhai for the purpose that we can have a comprehensive under- standing of the situation on ecology and environment of Lake Erhai. In this way we can have cognitive bases for the further relative work carried out in Lake Erhai and support some constructive opinions for ecological restoration work of Lake Erhai preferably.
柴达木察尔汗盐湖贝壳堤剖面介形类组合及其环境意义
,王强,彭金兰,陈光杰
第四纪研究 , 2008,
Abstract: 柴达木盆地察尔汗贝壳堤剖面记录了约39.7~17.514CkaB.P.期间古湖泊高湖面扩张、收缩的演化历史。剖面中丰富的介形类,皆为我国东部山间盆地~平原区系与西部高原区系常见种。依据青海地区现代介形类分布调查,可知研究剖面高湖面发育期为淡水湖,其中高分异度介形类组合代表近静水的浅湖环境,单种或近单种土星介大量出现层位指示缓流水环境,大量原生双壳类共生可能指示静水、较深水环境。据地层中介形类分布,自下而上划分为7个组合-沉积环境带,分别为:①少量湖沼种出现(积水洼地形成带)——湖泊前期,②单种缓流水种连续出现(湖泊初始形成带)——高湖面初始形成期,③高分异度组合、介形类富集(浅水大湖带)——高湖面水深加大期,④中分异度组合、介形类少量出现(深湖带)——高湖面最盛期,⑤中分异度组合、介形类少量出现、双壳类连续富集(湖泊变浅带)——高湖面略下降期,⑥缓流水介形类繁盛、双壳类多少不等(湖泊水位下降带)——古湖泊退缩期和⑦介形类稀少带——古湖泊快速消亡期。贝壳堤剖面所见双壳类在现代介形类调查区域没有发现,它们在地层中的出现,进一步指示大体相当MIS3阶段时期柴达木盆地比现代更温暖的气候背景,降水条件好于现代。
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