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141.
Seasonal and spatial distributions of phytoplankton biomass associated with monsoon and oceanic environments in the South China Sea 总被引:5,自引:3,他引:2
Seasonal variations of phytoplankton/chlorophyll-a (Chl-a) distribution, sea surface wind, sea height anomaly, sea surface temperature and other oceanic environments for long periods are analyzed in the South China Sea (SCS), especially in the two typical regions off the east coast of Vietnam and off the northwest coast of Luzon, using remote sensing data and other oceanographic data. The results show that seasonal and spatial distributions of phytoplankton biomass in the SCS are primarily influenced by the monsoon winds and oceanic environments. Off the east coast of Vietnam, Chl-a concentration is a peak in August, a jet shape extending into the interior SCS, which is associated with strong southwesterly monsoon winds, the coastal upwetling induced by offshore Ekman transport and the strong offshore current in the western SCS. In December, high Chl-a concentration appears in the upwelling region off the northwest coast of Luzon and spreads southwestward. Strong mixing by the strong northeasterly monsoon winds, the cyclonic circulation, southwestward coastal currents and river discharge have impacts on distribution of phytoplankton, so that the high phytoplankton biomass extends from the coastal areas over the northern SCS to the entire SCS in winter. These research activities could be important for revealing spatial and temporal patterns of phytoplankton and their interactions with physical environments in the SCS. 相似文献
142.
This work develops a top‐down modelling approach for storm‐event rainfall–runoff model calibration at unmeasured sites in Taiwan. Twenty‐six storm events occurring in seven sub‐catchments in the Kao‐Ping River provided the analytical data set. Regional formulas for three important features of a streamflow hydrograph, i.e. time to peak, peak flow, and total runoff volume, were developed via the characteristics of storm event and catchment using multivariate regression analysis. Validation of the regional formulas demonstrates that they reasonably predict the three features of a streamflow hydrograph at ungauged sites. All of the sub‐catchments in the study area were then adopted as ungauged areas, and the three streamflow hydrograph features were calculated by the regional formulas and substituted into the fuzzy multi‐objective function for rainfall–runoff model calibration. Calibration results show that the proposed approach can effectively simulate the streamflow hydrographs at the ungauged sites. The simulated hydrographs more closely resemble observed hydrographs than hydrographs synthesized using the Soil Conservation Service (SCS) dimensionless unit hydrograph method, a conventional method for hydrograph estimation at ungauged sites in Taiwan. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
143.
长三角房价收入比时空演变格局及收敛性研究 总被引:2,自引:1,他引:2
房价收入比是衡量房地产健康状况和探测居民住房支付能力的重要指标。以2008—2018年长三角307个区县为研究单元,运用数值-位序法则和趋势面分析对房价收入比的总体分布特征进行探究,利用LISA时间路径分析房价收入比的时空动态性特征,并检验区域房价收入比的收敛性。结果表明: ① 长三角房价收入比总体上呈上升趋势,空间上表现为东高西低、南高北低的格局,上海、浙江、江苏和安徽依次降低。② 上海和浙江南部房价收入比的空间结构更具动态性,而江苏和安徽更加稳定;长三角房价收入比的空间演化整体上具有较强的空间锁定效应和空间整合性。③ 长三角区县房价收入比整体上不存在σ收敛,但各时间段上均存在显著的绝对β收敛,且各省份内部也均存在着俱乐部收敛现象。城市群房价收入比的变动对居民的流动有着重要的指示作用,并具有扩散效应和虹吸效应。加强城市群房地产市场一体化建设,是促进城市群区域一体化发展的有效途径。 相似文献
144.
三维真实感地形建模与可视化 总被引:1,自引:1,他引:0
研究了三维真实地形建模与可视化的整个流程,利用OpenGL通用图形程序接口实现了基于DEM数据与遥感影像的三维地形的快速生成与仿真;并将三维地形生成技术应用到了天山公路三维地质灾害场景可视化中。详细阐述了以遥感影像作为地形纹理的处理方式与流程以及构建真实地形场景技术的方法和优化方案,提出了在实际应用中建立个性化三维地形系统的重要性。 相似文献
145.
Characterization of marine microplankton communities of Qingdao coastal areas using randomly amplified polymorphic DNA(RAPD) 总被引:1,自引:1,他引:0
Microplankton communities of three coastal sites of Qingdao, Shandong Province, China were investigated using RAPD (random amplified polymorphic DNA) molecular markers and morphological observations. Eight RAPD-primers were selected to amplify the DNA polymorphy. The genetic distances inferred from the pairwise similari-ties were calculated for the phylogenetic tree construction. Meantime, the traditional microscopic determination, a way of visualizing the species composition, was performed to detect the major taxa of microplanktons from all samples. Results showed that: (1) the band sharing index values were in the range of 0. 504 2-0. 763 2 among samples from the same sampling site at different time scales, while 0.406 5-0.685 7 among the samples from different stations at the same time scales, indicating that spatial variations of microplankton communities were more pronounced than temporal ones; (2) samples from the same station basically clustered together, cor-responding to the geographic distribution of the sampling sites; (3) diversity derived from genetic and morpho-logical data did not correspond with each other well. 相似文献
146.
???????????????????????????鹹????????????μ?????????????????????????????????????μ??????????????????1?????????????????????????????2???????????????μ????????????γ???????£???80??????????????????????????????????????????μ???????????????60???????3??????????????????????????????????????????????????????????????????????С??????????????????μ????????????????????????4???????????????????й?????γ?????????????????????????? 相似文献
147.
This study investigates the impact of climate change on rainfall, evapotranspiration, and discharge in northern Taiwan. The upstream catchment of the Shihmen reservoir in northern Taiwan was chosen as the study area. Both observed discharge and soil moisture were simultaneously adopted to optimize the HBV‐based hydrological model, clearly improving the simulation of the soil moisture. The delta change of monthly temperature and precipitation from the grid cell of GCMs (General Circulation Models) that is closest to the study area were utilized to generate the daily rainfall and temperature series based on a weather generating model. The daily rainfall and temperature series were further inputted into the calibrated hydrological model to project the hydrological variables. The studies show that rainfall and discharge will be increased during the wet season (May to October) and decreased during the dry season (November to April of the following year). Evapotranspiration will be increased in the whole year except in November and December. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
148.
福建东山岛地质灾害特征与成因初探 总被引:5,自引:5,他引:0
海岛是海上陆地国土和人类开发海洋的远涉基地及前进支点。海岛大幅度地快速增长的开发活动与工程建设使脆弱的海岛生态环境正遭受到严重威胁。东山岛是福建第二大岛,近10年随着水产养殖与育苗、风电建设、环岛公路和房地产开发等海岛利用和开发强度的加大,海岛地质灾害及潜在风险陡增。基于现场调查和遥感影像解译,分析东山岛赋存的地质灾害类型及其分布,初步探究了主要地质灾害的诱因,为更有效地保护和可持续性开发东山岛,制定合理长效规划、防灾与减灾对策提供准确依据,并为福建及周边基岩岛的地质灾害调查与防治提供实测数据参考。 相似文献
149.
ArcGIS中地理的处理可以通过Python脚本语言来完成.Python脚本语言结合ArcGIS地理工具,实现工作流自动地完成,可以在很大程度上简化数据生产的步骤,提高工作效率,进而保证数据质量.现以辽宁某地区的资产数据和路网数据,依据线性参考获得桩号为实践案例,介绍了在ArcGIS中利用Python批处理地理数据,提供了自动执行批量处理的解决方案[1]. 相似文献
150.
Pei-Sheng Chen Xiao-Hong Yang Hong-Guang Shan National Astronomical Observatories /Yunnan Observatory Key Laboratory for the Structure Evolution of Celestial Objects Chinese Academy of Sciences Kunming China 《中国天文和天体物理学报》2010,10(4)
We collected almost all Highly Processed Data Products(HPDP)of ISO SWS01 spectra for the Galactic visual carbon stars,infrared carbon stars,extreme carbon stars and carbon-rich proto-planetary nebulae(PPNs).Those infrared spectra are primarily analyzed and discussed.It is shown that either spectral shapes/peaks,or main molecular/dust features are evidenced to change in the sequence of visual carbon stars,infrared carbon stars,extreme carbon stars and carbon-rich PPNs.Statistically,in this sequence,continua are gradually changed from blue to red and locations of spectral peaks of continua are also gradually changed from short wavelengths to long wavelengths.In addition,in this sequence,intensifies of main molecular/dust features are also gradually changed from prominent in the short wavelengths to prominent in the long wavelengths.Furthermore,from 2MASS and IRAS photometric data,the sequence is also proved.Results in this paper strongly support the previous suggestion for the evolution sequence of carbon-rich objects in our Galaxy,that is the sequence of visual carbon stars→infrared carbon stars→extreme carbon stars→carbon-rich PPNs. 相似文献