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151.
Developing land use scenario dynamics model by the integration of system dynamics model and cellular automata model 总被引:8,自引:1,他引:8
HE Chunyang SHI Peijun CHEN Jin Li Xiaobing PAN Yaozhong LI Jing LI Yuechen & LI Jinggang Key Laboratory of Environmental Change Natural Disaster Ministry of Education of China Beijing Normal University College of Resources Science & Technology Beijing Normal University Beijing China 《中国科学D辑(英文版)》2005,48(11):1979-1989
Models of land use change are useful tools for un-derstanding the analysis of the cause and conse-quences of land use changes, assessing the impacts of land use system on ecological system and supporting land use planning and policy[1,2]. Modeling land use scenario changes and its potential impacts on the structure and function of the ecosystem in the typical regions are regarded as one of the good ways to un-derstand the interactive mechanism between land use system and ecological system[3―10… 相似文献
152.
153.
Hildegard?WestphalEmail author Iris?Surholt Christian?Kiesl Holger F. ?Thern Thomas?Kruspe 《Pure and Applied Geophysics》2005,162(3):549-570
Carbonate rocks are well known for their complex petrophysical behavior where, in contrast to siliciclastic rocks, different parameters, including porosity and permeability, usually are not directly related. This behavior is the result of thorough reorganization of porosity during diagenesis, and it turns prediction of reservoir quality of carbonate rocks into a challenge. The study presented here deals with the problem of utilizing NMR techniques in prediction of petrophysical properties in carbonates.We employ a visual porosity classification as a priori knowledge for better interpreting NMR data for prediction purposes. This allows for choice of suitable T2 cutoff values to differentiate movable from bound fluids adapted for the specific carbonate rock, thus resulting in better interpretation of NMR data. The approach of using a genetic pore type classification for adapting the conventional method for T2 cutoff determination, which originally was developed for siliciclastic rocks, is promising. Similarly, for permeability determination on the basis of NMR measurements, the classification of carbonate rocks based on porosity types also shows potential. The approach implemented here has the promise to provide a basis of standardized interpretation of NMR data from carbonate rocks.Acknowledgment We are grateful to Baker Hughes INTEQ, Celle, for permission to publish the results of this work. This study was part of I.S.s Masters Thesis at Hannover University that was carried out in collaboration with Baker Hughes INTEQ, Celle, Germany. We appreciate comments of an anonymous referee and PAGEOPH editor Brian J. Mitchell. 相似文献
154.
155.
通过岩心、薄片观察,从岩石学特征入手,结合测井资料,对塔里木盆地巴楚—麦盖提地区石炭系的陆源碎屑—碳酸盐混积岩和混积层系进行了研究。根据混积强度将混积岩划分为混积型碎屑岩、混积型碳酸盐岩和高度混积岩。巴楚组下泥岩段和中泥岩段发育混积型碎屑岩,巴楚组生屑灰岩段、中泥岩段和小海子组发育混积型碳酸盐岩,卡拉沙依组上泥岩段、巴楚组下泥岩段及巴什托局部地区的中泥岩段发育高度混积岩。高度混积岩出现在海退期沉积的碎屑岩段,代表了陆源碎屑—碳酸盐强烈混合的过渡性沉积环境。研究区石炭系可识别出4个三级层序,混积层系主要发育在海侵体系域早期和高位体系域晚期,以间断混合和相缘混合为主。研究认为混积强度是评价混合沉积环境性质的主要参数,并将其划分为4级。下泥岩段存在混积强度达3级以上的混积界面,能用于地层对比。最后,结合混合沉积特征讨论了构造运动和海平面变化对研究区石炭系层序组以上的混合沉积的控制作用。 相似文献
156.
Luděk Sýkora 《GeoJournal》1999,49(1):79-89
The article overviews the most important changes in the internal urban structure of Prague since 1989. Post-communist urban
development has been influenced by government-directed reforms of political and economic system, internationalisation and
globalisation, public policies favouring unregulated market development, economic restructuring in terms of deindustrialisation
and growth of producer services, and increasing social differentiation. The three most transparent processes of urban change
in Prague have been (1) commercialisation of the historical core; (2) revitalisation of some inner city neighbourhoods; and
(3) residential and commercial suburbanisation in the outer city.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
157.
为了研究东台吉乃尔盐湖卤水蒸发时的相化学,确定钾、镁和锂盐的结晶特性,在实验室内25℃等温蒸发实验基础上和自然条件下进行了冬夏季日晒蒸发试验.东台吉乃尔盐湖卤水是由氯化钠饱和的多组分复杂体系构成的.卤水中存在的离子是Na+、K+、Mg2+、Li+、Ca2+、B3+、SO42-和Cl-.试验数据与Na+、K+、Mg2+Cl-、SO42-KH2O五元体系介稳平衡数据进行了讨论和比较.Autenrieth相图被用来表示各数据间的关系和证明冬夏季蒸发时结晶行为的差别. 相似文献
158.
Alessandro Beghini Zdeněk P. Bažant R. Chambon D. Kolymbas I. Herle 《国际地质力学数值与分析法杂志》2004,28(4):365-372
159.
Visiting professors Václav Hanuš Jiří Vaněk Reviewer M. Krs 《Studia Geophysica et Geodaetica》1979,23(3):218-234
Summary The morphology of the Wadati-Benioff zone in the region of Central America, based on the distribution of 1377 earthquake foci, verified the existence of an intermediate aseismic gap and its relation to active andesitic volcanism, and the non-uniformity of subduction due to the hampering effect of the main structural features of the subducting Cocos plate. Four deep seismically active fracture zones, genetically connected with the process of subduction, and three fracture zones manifesting the possible boundary between the Americas and Caribbean plates were identified in the continental wedge. 相似文献
160.
Black band disease as a possible factor of the coral decline at the northern reef-flat of Yongxing Island,South China Sea 总被引:1,自引:0,他引:1
Black band disease(BBD),characterized by the Cyanobacterial dominated pathogenic consortium,is thought to play a key role in the global decline of the coral reef ecosystems.The present paper originally documents a case of BBD from Yongxing Island(Xisha Islands,South China Sea),and further probes the reasons of this abnormal phenomenon.Prior to 2007,corals at northern reef-flat of Yongxing Isand were in healthy growth.Catastrophic coral mortality occurred between 2007 and 2008.The 16S rRNA gene sequencing and PCR amplification,with universally conserved primers,were applied to detect the contagious bacterial community of the microbial mat.The results demonstrated that six bacterial divisions constituted the clone libraries derived from the BBD mat,and that Cyanobacteria are the most diversely represented group that inhabit BBD bacterial mats,despite the fact that species in five others divisions(α-Proteobacteria,γ-Proteobacteria,Bacteroidetes,Verrucomicrobia and Actinobacteria) are also consistently diverse within the BBD mats of diseased coral.Other factors such as coral bleaching,typhoons,ocean acidification and crown-of-thorns starfish outbreaks,are not primarily responsible for the coral mortality within such a short time interval.The disaster expansion of BBD associated with Cyanobacterial blooms is a more likely mechanism impacting these coral reefs.Excessive human activity enhances the eutrophication of the marine water of the reefal region and may result in occurrence of the BBD. 相似文献