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1.
潜在蒸散发量计算公式在贵州省适用性分析   总被引:1,自引:0,他引:1       下载免费PDF全文
利用贵州省18个气象站1961~2001年逐日气象资料,采用Penman-Monteith方程计算潜在蒸散发量,对以辐射和气温为基础的简化公式参数进行率定,对比分析不同计算公式推求的潜在蒸散发量之间的差异以及用于气候变化情景下预测适用程度。结果表明,各种潜在蒸散发量公式经参数率定后计算的多年平均蒸散发量相近,但变化趋势存在较大差异。与考虑综合气象因子对潜在蒸散发影响的Penman-Monteith公式计算结果相比,以辐射为基础的蒸散发公式在该地区的适用性较好,以气温为基础的蒸散发公式用于气候变化情景下潜在蒸散发量预测,结果偏大。  相似文献   

2.
土壤水资源的变化和补给特征研究   总被引:5,自引:0,他引:5  
夏自强  李琼芳 《水文》2001,21(5):1-5
阐述了土壤水资源的结构,利用实验和观测资料分析了土壤含水量、包气带蓄水量、土壤蒸散发量的空间分布特点,通过观测和模型模拟计算的成果分析了土壤蓄水量和土壤蒸散发量多年平均变化过程,以及不同地下水埋深时大气降水、地下水对土壤水资源补给过程和补给特点。  相似文献   

3.
夏季黑河流域蒸散发量卫星遥感估算研究   总被引:8,自引:0,他引:8       下载免费PDF全文
依据空气动力学方法和蒸散发量时间尺度扩展方案,利用MODIS资料和气象资料,计算中国西北内陆河黑河流域复杂地形下,2004年夏季7月蒸散发量空间分布及总量。利用Landsat-5TM资料对比分析发现,估算地表水热传输过程时,采用高分辨率遥感资料的估算结果受下垫面非均匀性影响程度,明显小于采用中分辨率资料。通过"金塔实验"湍流观测资料验证表明,利用高分辨率资料估算日蒸散发量的相对误差在10%以内。对月蒸散发量计算分析表明,黑河流域海拔2000m以上祁连山区,7月平均蒸散发量是海拔2000m以下山前地区的2.2倍,而山前平原区绿洲(NDVI>0.10区域)平均蒸散发量又是荒漠戈壁地区的12.3倍。因此,流域中下游绿洲地区特别是农业灌溉区是夏季主要水资源消耗区。  相似文献   

4.
农田蒸散发量变化规律分析   总被引:5,自引:0,他引:5  
王朝华 《水文》2005,25(3):35-37,55
根据冉庄水资源实验站大型地中蒸渗仪在种植小麦、玉米情况下的农田蒸散发量实测资料,分析了农田蒸散发量的时程及深度变化规律,提出了在实验条件下农田蒸散发量的数值范围。  相似文献   

5.
区域蒸散发量的气候学计算方法   总被引:6,自引:0,他引:6  
冯国章 《水文》1994,(3):7-11
本文介绍了一种计算区域蒸散发量的气候学方法。本法应用Bouchet区域蒸散发互补关系概念,以陕西省55个流域或区间的常规地面气候观测资料为基本输入,建立了区域蒸散发互补关系模型。该模型具有计算成果合理,精度较高,适应性广等特点。  相似文献   

6.
蒸散发对降雨径流预报的精度往往起决定作用,但目前尚不能可靠地量测,其计算方法也比较粗糙,是一个相对薄弱的环节。现就一种流域蒸散发计算方法作一探讨,以供有关部门参考。一、蒸发能力、陆面蒸散发能力在流域蒸散发计算中,区分燕发能力和陆面蒸散发能力的概念,有助于分清各种影响因素,分别进行计算,继而计算流域蒸散发量。蒸发能力。它是仅由大气状况所决定的,  相似文献   

7.
基于实测资料对日蒸散发估算模型的比较   总被引:1,自引:0,他引:1  
利用设置于江西省南昌县的新型高精度自动蒸渗仪,于2007年9月1日至2008年8月31日的实测陆面实际蒸散发过程,检验了面蒸散发互补关系模型CRAE (Complementary Relationship Areal Evapotranspiration)、GG模型 (Granger-Gray)、平流-干旱模型AA (Advection-Aridity)3个逐日路面实际蒸散发模型在不同时间尺度上的计算精度,并对计算误差的影响因素进行了讨论.结果表明:该地区实测年蒸散发量为746.1 mm,采用各模型的推荐经验参数对该地区蒸散发的估算结果误差较大,普遍干旱条件下蒸散发的计算值比观测值偏小,而湿润条件下的计算值偏大.通过对各模型的经验参数进行调整,各模型对年蒸散发量的计算精度大为提高,但逐日蒸散发过程的计算精度改进效果有限,在7日的时间尺度上,计算结果显著优于逐日的计算结果,在此时间尺度下,AA模型仍存在一定的系统误差,CRAE模型的估算精度相对较差,GG模型的总体计算效果相对最好.根据与蒸渗仪观测结果的对比分析,根据区域特征进行参数调整后的模型,需要在7日及更长时间尺度上,蒸散发模型的估算结果较为可靠.上述研究对全面认识陆面实际蒸散发特征、理解各蒸散发模型在不同时间尺度上的模拟能力、正确认识气候变化条件下的水循环特征具有重要意义.  相似文献   

8.
对新安江模型蒸散发计算的改进   总被引:4,自引:1,他引:4  
基于DEM构建数字流域水文模型,在此基础上,利用新安江模型作径流计算。利用陆面模式SSIB中大气动力阻抗法计算蒸散发的方法改进新安江模型的蒸散发计算,从而改进新安江模型对流域出流量的模拟,得到更为合理的陆面水文模型。以安徽水阳江流域为研究区域,利用改进前后的新安江模型进行径流模拟。结果表明,对新安江模型蒸散发计算的改进提高了模型对径流量的模拟效果。  相似文献   

9.
基于改进White方法的地下水蒸散发研究   总被引:2,自引:0,他引:2  
在依赖地下水的植被广泛分布的干旱半干旱地区,蒸散发是地下水排泄的主要方式,因而准确计算地下水蒸散发量,对地下水资源评价具有重要意义。目前水量残差法、地下水极限埋深法和地下水水位日动态法可以用于计算地下水蒸散发量,由于地下水动态信息容易获取,长期以来得到广泛关注。分析了利用地下水动态信息的White方法在计算地下水净补给量方面的不足之处,提出了改进的White方法,即利用相邻两天地下水位上升段的平均斜率计算地下水的净补给量,并利用数值模拟方法对改进的White方法的计算精度进行了评价,表明改进后的方法较原始方法精度提高了16%。最后利用苏贝淖流域实测的地下水动态数据,采用改进的White方法计算了地下水蒸散发量。研究成果对干旱区水资源可持续开发利用具有一定的科学意义和应用价值。  相似文献   

10.
基于陆地表面能量平衡系统对鄂尔多斯盆地北部海流兔河流域2012年蒸发量进行了反演,对蒸散发量的空间分布进行了分析并讨论了地下水位埋深对蒸发量的影响。结果表明:在枯水期海流兔河流域地表蒸散发的主要影响因素是地表土壤的含水率程度,而在丰水期的主要影响因素是植被覆盖状况和地表土壤的湿润程度;根据计算,海流兔河流域2012年总蒸散发量约为8.76×108 m3。  相似文献   

11.
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco.  相似文献   

12.
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414.  相似文献   

13.
Robert L. Linnen   《Lithos》2005,80(1-4):267-280
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species.  相似文献   

14.
Some olistolites reworked in a Tertiary flysch of Mount Parnon (Peloponnesus, Greece) exhibit a Late Permian assemblage, dominated by Paradunbarula (Shindella) shindensis, Hemigordiopsis cf. luquensis and Colaniella aff. minima. This association corresponds to the Late Wuchiapingian (=Late Dzhulfian), a substage whose algae and foraminifera are generally little known. Contemporaneous limestones crop out in the middle part of the Episkopi Formation in Hydra, but they are rather commonly reworked in Mesozoic and Cainozoic sequences. The palaeobiogeographical affinities shared by the foraminiferal markers of Greece, southeastern Pamir, and southern China, are very strong (up to the specific level), and are congruent with the Pangea B reconstructions. To cite this article: E. Skourtsos et al., C. R. Geoscience 334 (2002) 925–931.  相似文献   

15.
PALEONTOLOGY     
正20141596 Liu Yunhuan(School of Earth Sciences and Resources,Chang’an University,Xi’an 710054,China);Shao Tiequan Early Cambrian Quadrapyrgites Fossils of Xixiang Boita in Southern Shaanxi Province(Journal of Earth Sciences and Environment,ISSN1672-6561,CN61-1423/P,35(3),2013,p.39-43,3 illus.,20 refs.)  相似文献   

16.
正20141719 Chen Zhijun(State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China);Chen Jianguo Automated Batch Mapping Solution for Serial Maps:A Case Study of Exploration Geochemistry Maps(Journal of Geology,ISSN1674-3636,CN32-1796/P,37(3),2013,p.456-464,2 illus.,2 tables,10 refs.)  相似文献   

17.
正20140962 Chen Fenning(Xi’an Institute of Geology and Mineral Resources,Xi’an710054,China);Chen Ruiming Late Miocene-Early Pleistocene Ostracoda Fauna of Gyirong Basin,Southern Tibet(Acta Geologica Sinica,ISSN0001-5717,CN11-1951/P,87(6),2013,p.872-886,6illus.,56refs.)  相似文献   

18.
PETROLOGY     
正1.IGNEOUS PETROLOGY20142008Cai Jinhui(Wuhan Center,China Geological Survey,Wuhan 430205,China);Liu Wei Zircon U-Pb Geochronology and Mineralization Significance of Granodiorites from Fuzichong Pb-Zn Deposit,Guangxi,South China(Geology and Mineral Resources of South China,ISSN1007-3701,CN42-1417/P,29(4),2013,p.271-281,7illus.,  相似文献   

19.
正20141205Cheng Weiming(State Key Laboratory of Resources and Environmental Information System,Institute of Geographic Sciences and Natural Resources Research,CAS,Beijing 100101,China);Xia Yao Regional Hazard Assessment of Disaster Environment for Debris Flows:Taking Jundu Mountain,Beijing as an  相似文献   

20.
正20141266Fan Chaoyan(Guangdong Provincial Key Laboratory of Mineral Resources and Geological Processes,Guangzhou 510275,China);Wang Zhenghai On Error Analysis and Correction Method of Measured Strata Section with Wire Projection Method(Journal of  相似文献   

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