897 resultados para disaster
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Climate change is amongst the most dreaded problems of the new millennium. Bangladesh is a coastal country bounded by Bay of Bengal on its southern part and here natural disasters are an ongoing part of human life. This paper discusses about the possible impact of climate change through tropical cyclones, storm surges, coastal erosion and sea level rise in the coastal community of Bangladesh and how they cope with these extreme events by the help of mangrove ecosystem. Both qualitative and quantitative discussions are made by collected data from different research work those are conducted in Bangladesh. Mangrove ecosystem provides both goods and services for coastal community, helps to improve livelihood options and protect them from natural disaster by providing variety of environmental support
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O município de Petrópolis, palco de recorrente de problemas ambientais envolvendo movimentos de massa concentrados historicamente na sua área mais urbanizada, os distritos Sede e Cascatinha, vive nas últimas décadas um crescimento populacional que se orienta basicamente para antigas áreas rurais de Itaipava, Pedro do Rio e Posse. O objetivo geral da pesquisa é investigar como este crescimento vem ocorrendo, analisando as características geológico-geomorfológicas dos novos espaços ocupados, os fatores predisponentes às novas condições de risco envolvendo os movimentos de massa e as inundações. Assim, foi elaborado um panorama sócio-evolutivo do processo de ocupação do solo em Petrópolis, considerando especialmente a dinâmica demográfica registrada nos distritos através dos censos demográficos a partir da década de 1940. Utilizando o geoprocessamento como ferramenta e a classificação visual de segmentação de OrtofotosCarta IBGE na escala 1: 25.000, foram produzidos mapas de uso do solo para o município e distritos detalhando a área ocupada. Com o fim de atender ao diagnóstico das situações de risco foi realizado o levantamento da situação atual da ocorrência dos movimentos de massa e inundações no município, comparando levantamentos anteriores e verificando a distribuição das ocorrências e a população atingida. Por fim, a avaliação da execução da política de desenvolvimento e expansão urbana definida no Plano Diretor de Petrópolis e na Lei de Uso, Parcelamento e Ocupação do Solo, analisando o zoneamento e seus usos (rural, rururbano, urbano e zona de proteção especial) resultando no entendimento de como os aspectos normativos vem sendo tratados, naquilo que são respeitados e naquilo que não são cumpridos na dinâmica da ocupação do espaço, levantando as ações de prevenção, ou não, dos problemas ambientais. Contudo, a definição dos objetivos do trabalho teve dois momentos. O primeiro com a análise da expansão urbana construindo novas condições de risco e o segundo momento, lamentavelmente, aquele no qual as evidências ganharam contorno de realidade com o ocorrido em dezembro de 2010 e em janeiro de 2011, principalmente quando inundações bruscas associadas aos deslizamentos de terra nas encostas atingiram áreas de Petrópolis e de outros municípios da região Serrana do Estado do Rio de Janeiro, certamente, a maior tragédia ambiental ocorrida no Centro-Sul do país até então. Com mais de 900 mortos, centenas de desaparecidos e milhares de desabrigados e desalojados, os eventos suplantaram os objetivos do trabalho, colocando novas questões, ao mesmo tempo em que a realidade demonstrou a coerência e pertinência daqueles objetivos com os problemas apresentados. Assim, dentre os objetivos passou a constar também a verificação in loco das conseqüências de movimentos de massa e inundações nas áreas apontadas anteriormente, como foi o caso do vale do Rio Santo Antônio em Itaipava. O trabalho, assim, se pautou por indicar a necessidade ter-se maior atenção às novas áreas de ocupação no município, considerando a natureza do território, contribuindo como um subsídio na prevenção ao risco.
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The aim of this research is to study the impact of religious coping, social support and subjective severity on Posttraumatic Growth (PTG) in people who lost their homes after the earthquake in Chile in 2010 and who now live in transitional shelters. One hundred sixteen adult men and women were evaluated using a subjective severity scale, the Posttraumatic Growth Inventory (PTGI), the Multidimensional Scale of Perceived Social Support (MSPSS) scale of social support and the Brief RCOPE scale of religious coping. The multiple linear regression analysis shows that social support and positive religious coping have an impact on PTG. On using a bootstrap estimate, it was found that positive religious coping fully mediates the relationship between subjective severity and PTG.
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244 p.
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Tendo como panorama um bairro destruído pelas chuvas em 2010 na cidade de Niterói/RJ (Morro do Bumba) e um questionamento sobre uma tendência individualizante nas práticas psicológicas, esta pesquisa objetiva pensar práticas e efeitos da psicologia em situações de emergências e desastres. Utilizando falas de especialistas neste tema, acompanhando uma certa reivindicação de que a Psicologia das Emergências e dos Desastres seja um novo campo, uma nova disciplina, trazemos um tensionamento entre planejamentos de atuação, falas oficiais e experiências do que foi possível fazer concretamente no Morro do Bumba, pelos profissionais surpreendidos em meio ao caos daqueles dias. Assim, o presente trabalho se propõe a passear por práticas sorrateiras, intervenções subversivas, transdisciplinares, positivando que nenhuma experiência em psicologia é neutra ou objetiva na medida em que o campo de atuação provoca deslocamentos em nossos sistemas de pensamento. Neste movimento de trazer as possíveis atuações psi em resposta aos desastres ocorridos em Niterói/RJ, ante a falta de políticas públicas necessárias à assistência da população desabrigada, pensando historicamente a própria ocupação dos morros no Rio de Janeiro.
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Em janeiro de 2011, o grande número de escorregamentos naturais e induzidos que afetaram a Região Serrana do Estado do Rio de Janeiro, durante o Megadesastre, são processos destruidores de grande impacto, mas com tempo de recorrência maior. Em particular a bacia do rio Vieira (noroeste de Teresópolis), afetada pelo evento, apresentou magnitude espetacular do desastre registrado, com os materiais mobilizados em fluxos gravitacionais de massa atingindo quilômetros de distâncias das suas escarpas principais, o que causou, horas depois, prejuízos significativos. A pesquisa da presente dissertação discutiu a caracterização destes processos e dos ambientes deposicionais, a partir da análise das feições sedimentológicas e apreciação das características mecânicas, do vale do rio Vieira para estabelecer base de conhecimento da evolução da paisagem local. O método de trabalho utilizou o reconhecimento dos condicionantes geológicos e a leitura do registro sedimentar. A corrida de massa do Vieira foi zoneada em diferentes estágios de comportamento baseado na classificação de fluxos gravitacionais de massa de Middleton e Hampton (1973). Esta classificação é adequada para linha de pesquisa, pois os autores definem fluxos gravitacionais de sedimentos como um termo geral para fluxos de sedimentos ou misturas sedimentos/fluidos, que fluem sob a ação da gravidade. Os resultados obtidos caracterizam o fenômeno do ponto de vista geológico, estratigráfico e geomorfológico. Uma corrida de massa afetou o canal do rio Vieira desde a sua nascente, na cota 1750m, até o fim da sua planície de inundação, na cota 900m; o movimento de massa com extensão de 7,5km, 30-100m de largura máxima e 4m de espessura média, causou diretamente 86 mortes e a destruição de casas e lavouras da zona rural do bairro Vieira, Teresópolis-RJ. O fluxo gravitacional do Vieira aparentemente contou com diferentes condicionantes e envolveu diferentes fases, passando pelo debrisflow e pelo mudflow, provavelmente em diferentes pulsos, e no seu estágio final para o waterflow.
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•2011 PICES Science: A Note from the Science Board Chairman (pp. 1-6) •2011 PICES Awards (pp. 7-9) •Beyond the Terrible Disaster of the Great East Japan Earthquake (pp. 10-12) •A New Era of PICES-ICES Scientific Cooperation (p. 13) •New PICES Jellyfish Working Group Formed (pp. 14-15) •PICES Working Group on North Pacific Climate Variability (pp. 16-18) •Final U.S. GLOBEC Symposium and Celebration (pp. 19-25) •2011 PICES Rapid Assessment Survey (pp. 26-29) •Introduction to Rapid Assessment Survey Methodologies for Detecting Non-indigenous Marine Species (pp. 30-31) •The 7th International Conference on Marine Bioinvasions (pp. 32-33) •NOWPAP/PICES/WESTPAC Training Course on Remote Sensing Data Analysis (pp. 34-36) •PICES-2011 Workshop on “Trends in Marine Contaminants and their Effects in a Changing Ocean” (pp. 37-39) •The State of the Western North Pacific in the First Half of 2011 (pp. 40-42) •Yeosu Symposium theme sessions (p. 42) •The Bering Sea: Current Status and Recent Events (pp. 43-44) •News of the Northeast Pacific Ocean (pp. 45-47) •Recent and Upcoming PICES Publications (p. 47) •New leadership for the PICES Fishery Science Committee (p. 48)
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This paper describes the resettlement process of a community devastated by annual floods, to newly constructed housing in Pune, India. The relocation from Kamgar Putala slum to a housing society at Hadapsar was organized by a community-led NGO partnership in 2004. The housing development was coordinated by the local NGO Shelter Associates with significant community participation. The housing has been revisited in 2010 to evaluate the sustainability of the resettlement project’s delivery model via stakeholder perception. The process of organizing for resettlement after natural disaster is described along with the implementation and evaluation of the new housing nearly six years after initial occupation. The strong partnership approach overcame a series of political and financial hurdles at various stages of the relocation project. The story of resettling Kamgar Putala is detailed alongside an outline of the current political climate for an alternative slum-upgrading policy in India and Pune. The advantages of an empowered community supported by an influential local NGO demonstrate a commendable team effort which has tackled the threat of floods. The paper highlights the merits of a community-led partnership approach to housing development for achieving sustainable urban development as well as the alleviation of poverty in a developing context.
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After earthquakes, licensed inspectors use the established codes to assess the impact of damage on structural elements. It always takes them days to weeks. However, emergency responders (e.g. firefighters) must act within hours of a disaster event to enter damaged structures to save lives, and therefore cannot wait till an official assessment completes. This is a risk that firefighters have to take. Although Search and Rescue Organizations offer training seminars to familiarize firefighters with structural damage assessment, its effectiveness is hard to guarantee when firefighters perform life rescue and damage assessment operations together. Also, the training is not available to every firefighter. The authors therefore proposed a novel framework that can provide firefighters with a quick but crude assessment of damaged buildings through evaluating the visible damage on their critical structural elements (i.e. concrete columns in the study). This paper presents the first step of the framework. It aims to automate the detection of concrete columns from visual data. To achieve this, the typical shape of columns (long vertical lines) is recognized using edge detection and the Hough transform. The bounding rectangle for each pair of long vertical lines is then formed. When the resulting rectangle resembles a column and the material contained in the region of two long vertical lines is recognized as concrete, the region is marked as a concrete column surface. Real video/image data are used to test the method. The preliminary results indicate that concrete columns can be detected when they are not distant and have at least one surface visible.
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This paper describes the resettlement process of a community devastated by annual floods, to newly constructed housing in Pune, India. The relocation from Kamgar Putala slum to a housing society at Hadapsar was organized by a community-led NGO partnership in 2004. The housing development was coordinated by the local NGO Shelter Associates with significant community participation. The housing has been revisited in 2010 to evaluate the sustainability of the resettlement project's delivery model via stakeholder perception. The process of organizing for resettlement after natural disaster is described along with the implementation and evaluation of the new housing nearly six years after initial occupation. The strong partnership approach overcame a series of political and financial hurdles at various stages of the relocation project. The story of resettling Kamgar Putala is detailed alongside an outline of the current political climate for an alternative slum-upgrading policy in India and Pune. The advantages of an empowered community supported by an influential local NGO demonstrate a commendable team effort which has tackled the threat of floods. The paper highlights the merits of a community-led partnership approach to housing development for achieving sustainable urban development as well as the alleviation of poverty in a developing context. © 2011 Taylor & Francis.
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目前全球缺水、水污染、洪涝灾害以及水土流失仍然非常严重,尤其在我国北方地区。流域水文模型可用来进行不同需水管理的情景分析,为解决我国水问题提供科学依据。分布式水文模型是流域水文模型的发展方向,具有显著特点:1)应用前景广泛,不仅可以模拟流域水文过程,还可以协助模拟泥沙或污染物的运移过程,为水利工程设计、水土保持、环境保护等领域提供技术支持;2)能够预测流域土地利用或气候变化下的流域水文响应过程变化,为管理部门提供决策支持;3)模型所需要的参数全部具有物理意义,可通过实际测量确定,适合模拟实测系列较短或是无观测流域的水文过程;4)对于目前国际水文界的前沿问题—水文尺度转换提供了一种有效的解决途径。 然而分布式水文模型还不完善,如1)真实性问题。对一些水文过程和边界条件还不确定。2)尺度转换问题。目前很少考虑尺度对参数有效性的影响。3)检验问题。还无法判断对有些难以测量的水文状态变量的模拟正确与否。4)计算时间和数据存储的问题。有些分布式水文模型虽然具有很强的水文物理基础和完善的模型结构,但是计算时间过长和(或)数据存储过大,难以应用。上述问题的核心就是对分布式水文模型的核心—单元水文模型的研究不够,需要为进一步完善单元水文模型进行研究。 本文采用饱和入渗理论、Saint-Venant方程、Richards方程、Penman-Monteith方程等等构建了以有限差分法求解的适用于森林流域的单元水文模型,并通过实验室模拟试验和坡地径流场资料进行了验证,主要结论为: 通过不同坡度和不同雨强下的室内坡面产汇流实验模拟,表明:该模型模拟的坡面流和壤中流过程与实测过程基本一致,峰现时间、径流历时、峰值流量、出流总量模拟值与实测值的相对误差均较小,基本小于10%。模型的模拟精度较高,实用性较强,为深入研究壤中流机制和改进流域降雨-径流模型提供了理论依据。 通过坡地径流观测场实测资料的验证,表明:该模型模拟的坡面流过程精度较高,累计流量的精度更高于小时过程的精度,离差系数、效率系数、确定系数均较理想,具有应用价值,有助于改善分布式水文模型在森林流域的模拟效果。
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Thermally induced evolution of phase transformations is a basic physical-chemical process in the dissociation of gas hydrate in sediment (GHS). Heat transfer leads to the weakening of the bed soil and the simultaneous establishment of a time varying stress field accompanied by seepage of fluids and deformation of the soil. As a consequence, ground failure could occur causing engineering damage or/and environmental disaster. This paper presents a simplified analysis of the thermal process by assuming that thermal conduction can be decoupled from the flow and deformation process. It is further assumed that phase transformations take place instantaneously. Analytical and numerical results are given for several examples of simplified geometry. Experiments using Tetra-hydro-furan hydrate sediments were carried out in our laboratory to check the theory. By comparison, the theoretical, numerical and experimental results on the evolution of dissociation fronts and temperature in the sediment are found to be in good agreement.
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The hydraulic conductivity function of fractures is a key scientific question to describe and reveal the process and the role of water seepage reasonably. In this paper, the generation technology of random fracture network and the latest numerical computation method for equivalent permeability tensor of fracture network are applied to analyze the landslide located at Wangjiayuanzi in Wanzhou District of Chongqing by simulating the changes of the seepage field caused by the running of the Three Gorges Reservoir. The influences of the fracture seepage on the seepage field and stability of the landslide were discussed with emphasis. The results show that the fractures existing in the soil increase the permeability coefficient of the landslide body and reduce the delay time of the underground water level in the landslide which fluctuates relative to the water level of reservoir,that causes the safe coefficient of the slope changes more gently than that of the same slope without fractures. It means, if only water level fluctuating condition is concerned, the fractures existing in the soil plays a positive role to the stability of slopes.
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A depth-averaged two-dimensional hydrodynamics model and a two-dimensional water quality model, bases on the alternating direction implicit (ADI) method, is developed to study the distribution characteristics of total phosphorus (TP) in Taihu Lake. Wind stress, the pollution source from the inflow rivers, releasing rate of TP from the bottom sediment and water diversion from Yangtze River are the effecting factors of TP distribution. By using the model proposed in this paper, the concentration field of the total phosphorus was simulated, which leads to the conclusion that the flow field has a great influence on the spatial and temporal distribution of TP in the Taihu Lake.
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干旱胁迫是全球范围内影响植物生存、生长和分布的重要环境因子。岷江上游干旱河谷区,由于生态环境的脆弱性和长期人类活动的干扰和过度利用,导致植被严重退化,水土流失加剧,山地灾害频繁,干旱化和荒漠化趋势明显。这种趋势若不能遏制,将严重阻碍区域社会经济的快速协调发展,并且威胁成都平原地区的发展和长江中下游地区的生态安全。因而开展干旱河谷生态恢复研究成为解决这些问题的关键。水分匮乏是限制干旱河谷生态恢复的关键因子,在全球气候变化的背景下,干旱胁迫在区域尺度上可能会更加严重,并使干旱河谷的生态环境更加恶化。因此,深入研究干旱河谷乡土植物对干旱胁迫的响应和适应机理,具有非常重要的理论和实践意义。 本论文以岷江上游干旱河谷的三种乡土豆科灌木,白刺花(Sophora davidii)、小马鞍羊蹄甲(Bauhinia faberi var. microphylla)和小雀花(Campylotropics polyantha)理论和实践意义。为研究对象,在人工控制条件下设计了4-5个连续性干旱胁迫处理,系统地研究了灌木幼苗的生长、生物量积累和水分利用效率(WUE)、形态结构和生理过程等对干旱胁迫的反应,揭示了幼苗的干旱适应能力及种间差异。主要研究结论如下: 1) 灌木生长和繁殖对干旱胁迫的反应 在干旱胁迫下,幼苗生长速率显著减小,叶片衰老和脱落比率增大,这些变化随着胁迫强度的增加具有累积效应。叶片比茎对干旱胁迫的反应更敏感。在严重干旱胁迫下,幼苗的有性繁殖被限制,但在中等程度干旱胁迫下,幼苗的有性繁殖能力被提高。 2) 灌木生物量积累及其分配和WUE对干旱胁迫的反应 在干旱胁迫下,灌木各器官的生物量都显著减小,但是生物量的分配侧重于地下部分,使得根茎比在干旱条件下增大。幼苗的耗水量(WU)随着干旱胁迫的增加而显著减少。白刺花和小马鞍羊蹄甲WUE在干旱胁迫下降低;小雀花的WUE在中等干旱胁迫下升高。 3) 灌木叶片结构特征对干旱胁迫反应 白刺花叶片具有较为典型的旱生型结构,而小马鞍羊蹄甲和小雀花则为中生型结构。在1至2年的干旱胁迫下,灌木叶片结构组成未发生本质性的改变,主要是细胞大小的变化。在中等和严重干旱胁迫下,叶肉组织厚度明显减小;并且气孔和表皮细胞面积也显著减小,气孔和表皮细胞密度显著增大;叶肉细胞层数、P/S值、表皮厚度等无显著变化。 4) 灌木对干旱胁迫的生理响应 气体交换参数和叶片相对含水量(RWC)在中等干旱胁迫下发生了明显的改变,而叶绿素荧光参数和光合色素含量在严重干旱胁迫下才发生显著变化。在干旱胁迫下,净光合作用速率(Pn)、气孔导度(gs)和RWC呈下降趋势,而叶片温度(Tl)呈增加趋势,蒸腾速率(Tr)的变化不明显。除了日最大Pn减小以外,干旱胁迫对气体交换参数的日变化无显著影响,但是对光合-光响应曲线有显著的影响,使有效光合时间缩短。在严重干旱胁迫下光系统受到损害而代谢减弱,PSⅡ中心的内禀光能转换效率(Fv/Fm)、量子产量(Yield)、光化学淬灭参数(qP)显著降低,而非光化学淬灭参数(NPQ)明显增加。气孔限制和非气孔限制对Pn的影响与干旱胁迫强度有关。在中度胁迫下,气孔限制起主导作用,在严重胁迫下非气孔限制起主导作用,40% FC水分条件可能是灌木由气孔限制向非气孔限制的转折点。 5) 灌木对干旱胁迫的适应能力及其种间差异 三种灌木对干旱胁迫具有较好的适应能力,即使在20% FC,幼苗未因干旱胁迫III而死亡;80% FC适宜于幼苗生长。白刺花生长速率慢,耗水量较少,具有较强的耐旱和耐贫瘠能力,并具有干旱忍受机制,能够在较干旱的环境中定居和生长。小马鞍羊蹄甲和小雀花,生长快,水分消耗量较大,尤其是小雀花,对干旱胁迫的忍受能力较弱,具有干旱回避机制,因而适宜于在较为湿润的生境中生长。综合分析表明,生长速率较慢的物种抗旱能力较强,其更适宜于作为干旱地区植被恢复物种。 Drought is often a key factor limiting plant establishment, growth and distribution inmany regions of the world. The harsh environmental conditions and long-termanthropogenic disturbance had resulted in habitat destruction in the dry valley ofMinjiang river, southwest China. Recently, it tended to be more severe on the vegetationdegradation, soil erosion and water loss, natural disaster, as well as desertification, whichimpact on regional booming economy and harmonious development, and would be verydangerous to the environmental security in the middle and lower reaches of Yangzi River.Therefore, ecological restoration in the dry valley is one of the vital tasks in China. Waterdeficit is known to affect adversely vegetation restoration in this place. Moreover, in thecontext of climate change, an increased frequency of drought stress might occur at aregional scale in the dry valleys of Minjiang River. The selection of appropriate plantingspecies for vegetation restoration in regard to regional conditions is an important issue atpresent and in further. The research on responses of indigenous species to drought stresscould provide insights into the improvement of the vegetation restoration in the dry valleys of Minjiang River. In this paper, the responses of three indigenous leguminous shrubs, Sophora davidii,Bauhinia faberi var. microphylla and Campylotropics polyantha, to various soil watersupplies were studied in order to assess drought tolerance of seedlings, and to compare interspecific differences in seedlings’ responses to drought stress. The results were as follows: 1 Growth and reproduction of shrubs in response to drought stress Seedling growth reduced significantly while leaf senescence accelerated underdrought stress, the cumulative responses to prolonged drought were found. The capacityfor reproduction was limited by severe drought stress, and improved by moderate droughtstress. Leaf responses were more sensitive than shoot to various water supplies. 2 WUE, biomass production and its partitioning of shrubs in response to drought stress Drought stress reduced significantly the total dry mass and their components ofseedlings, and altered more biomass allocation to root system, showing higher R/S ratiounder drought. Water use (WU) and water-use efficiency (WUE) of both S. davidii and B.faberi var. microphylla declined strongly with drought stress. The WU C. polyantha ofalso declined with drought stress, but WUE improved under moderate drought stress. 3 Anatomical characteristics and ultrastructures of leaves in response to drought stress There were xeromorphic for S. davidii leaves and mesomorphic for B. faberi var.microphylla and C. polyantha at the all water supplies. The foundational changes in leafstructures were not found with drought stress. However, mesophyll thickness, the areas ofstomatal and epidermis reduced slightly while the densities of stomatal and epidermisincreased under severe drought stress. Variations in these parameters could mainly be duoto cell size. Other structures did not displayed significant changes with drought stress. 4 Physiological responses of shrubs to drought stress The gas exchange parameters and leaf relative water content (RWC) were affectedby moderate stress, while chlorophyll fluorescence and chlorophyll content were onlyaffected by severe stress. Drought stress decreased net photosynthesis rate (Pn), stomatalconductance, light-use efficiency and RWC, and increased leaf temperature. Therespiration rates (Tr) were kept within a narrower range than Pn, resulting in aprogressively increased instantaneous water use effiecency (WUEi) under drought stress.Moreover, drought stress also affected the response curve of Pn to RAR, there was adepression light saturation point (Lsat) and maximum Pn (Pnmax) for moderate andsevere stressed seedling. However, diurnal changes of gas exchange parameters did notdiffer among water supplies although maximum daily Pn declined under severe stress.VISevere stress reduced Fv/Fm, Yield and qP while increased NPQ and chlorophyll content.Photosynthetic activity decreased during drought stress period due to stomatal andnon-stomatal limitations. The relative contribution of these limitations was associatedwith the severity of stress. The limitation to Pn was caused mainly by stomatal limitationunder moderate drought stress, and by the predominance of non-stomatal limitation undersevere stress. In this case, 40% FC water supply may be a non-stomatal limitation 5 Interspecific differences in drought tolerance of shrubs Three shrubs exhibited good performance throughout the experiment process, evenif at 20% FC treatment there were no any seedlings died, 80% FC water supply wassuitable for their establishment and growth. S. davidii minimized their water loss byreducing total leaf area and growth rate, as well as maintained higher RWC and Pncompared to the other two species under drought stress, thus they might be more tolerantto the drought stress than the other two species. On the contrary, it was found that C.polyantha and B. faberi var. microphylla had higher water loss because of their stomatalconductance and higher leaf area ratios. They reduced water loss with shedding theirleaves and changing leaf orientation under drought stress. Based on their responses, thestudied species could be categorized into two: (1) S. davidii with a tolerance mechanismin response to drought stress; (2) C. polyantha and B. faberi var. microphylla withdrought avoidance mechanism. These results indicated that slow-growing shrub speciesare better adapted to drought stress than intermediate or fast-growing species in present orpredicted drought conditions. Therefore, selecting rapid-growing species might leavethese seedlings relatively at a risk of extreme drought.