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UV-B辐射增强对壶状臂尾轮虫摄食的影响 总被引:4,自引:0,他引:4
研究了UV-B辐射条件下壶状臂尾轮虫(Brachionusurceus)对6株海洋微藻:小球藻(Chlorellasp.)、绿色巴夫藻(Pavlovauiridis)、扁藻(Tetraselmischuii)、球等鞭金藻8701(IsochrysisgalbanaPark8701)、牟氏角毛藻(Chaetocerosmuelleri)和小新月菱形藻(Nitzschiaclostertum)的室内摄食实验。结果表明,UV-B辐射增强对壶状臂尾轮虫的摄食有显著的抑制作用。与对照组相比,壶状臂尾轮虫对给定饵料单胞藻的滤水率和摄食率都随UV-B辐射剂量的增大而显著减小(P<0.05)。而且壶状臂尾轮虫对每一种饵料单胞藻的滤水率和摄食率是不相同的,这说明壶状臂尾轮虫对饵料单胞藻是有选择性的。 相似文献
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The Climate Forecast Systems (CFS) datasets provided by National Centers for Environmental Prediction (NCEP), which cover the time from 1981 to 2008, can be used to forecast atmospheric circulation nine months ahead. Compared with the NCEP datasets, CFS datasets successfully simulate many major features of the Asian monsoon circulation systems and exhibit reasonably high skill in simulating and predicting ENSO events. Based on the CFS forecasting results, a downscaling method of Optimal Subset Regression (OSR) and mean generational function model of multiple variables are used to forecast seasonal precipitation in Guangdong. After statistical analysis tests, sea level pressure, wind and geopotential height field are made predictors. Although the results are unstable in some individual seasons, both the OSR and multivariate mean generational function model can provide good forecasting as operational tests score more than sixty points. CFS datasets are available and updated in real time, as compared with the NCEP dataset. The downscaling forecast method based on the CFS datasets can predict three seasons of seasonal precipitation in Guangdong, enriching traditional statistical methods. However, its forecasting stability needs to be improved. 相似文献
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沃克巷是西部大盆地中NW向延伸的地带,长700km,宽100-300km.Krantz的奇数轴模式被用来建立内华达西部沃克巷中沃克湖和Excelsior-Coaldale两构造片的三维应变模型。地震震源机制断层/辅助平面与航天飞机成像雷达-B(SIR-B)图像上的一条构造线平行或近于平行。地震震源机制表明Excelsior-Coaldale构造片断层为走向滑动,而沃克湖构造片断层以倾向滑动为主。三 相似文献
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准噶尔东部SAR与TM复合图像处理及其地质应用 总被引:1,自引:0,他引:1
利用航天SAR与TM复合图像对准噶尔东部将军戈壁地区铀成矿环境与成矿条件进行研究。讨论了将军戈壁的地质背景、铀源条件、铀矿化与氧化还原带的关系,提出了铀成矿的若干有利条件,预测了铀成矿远景区并选出找矿的重点层位。 相似文献
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