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Validation of three infiltration models on purple soil under simulated rainfall

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Progress in Natural Science:Materials International 2007年第9期17卷 1059-1066页

作者： Wang Yukuan1,2,fu Bin1,3,xu Pei1,2,Wang Daojie1,2,Wang Xiantuo1,3 and Wang Yongqiang1,3(1.Key Laboratory of mountain Surface Process and Hazards,chinese academy of Seiences,Chengdu 610041,china 2.Institute of mountain Hazards and Environment,chinese academy of sciences,Chengdu 610041,china 3.Graduate University of the chinese academy of sciences,Beijing 100049,china) Key Laboratory of mountain Surface Process and Hazards Chinese Academy of Seiences Chengdu 610041 China Institute of mountain Hazards and Environment， chinese academy of sciences， Chengdu 610041 China Graduate University of the chinese academy of sciences Beijing 100049 China

So as to find models suitable for the prediction of water infiltration in purple soil,infiltration rates simulated by three popular empirical infiltration models,Horton model,Kostiakov model,and the modified Kostiakov model,were compared by using those observed results on slope in purple soil under rainfall simulation.28 sets of infiltration data were divided into two parts for parameter estimation and validation *** performance of the three infiltration models was evaluated with the Nash and Sutcliffe efficiency *** results show that the percent for Nash and Sutcliffe efficiency greater than 0.7 is about 69.7% for the Horton model,and 48.48%,and 54.55% for the Kostiakov model and the modified Kostiakov model,*** model is better than Kostiakov model and the modified Kostiakov model in most rain events in the ***,Kostiakov model is still suitable for reasonable prediction of the infiltration in purple soil sloping farmland because fewer parameters are ***,rainfall intensity has significant effects on the parameter values used in the simulation *** simulation results can be improved by choosing suitable parameters according to the rainfall intensity.

关键词： infiltration model sloping farmland purple soil rainfall simulation

THE MOTION PROPERTIES OF THE STARS CONFINED TO THE SYMMETRIC AXIS OF AN OSCILLATION KUZMIN DISK

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南京大学学报(自然科学) 1997年第4期 151-153页

作者： fu yanning 1,2) \ \ Sun Yisui 1) ( 1) Department of Astronomy, nanjing University, 2.0008, nanjing, PRC 2) purple mountain observatory, Academia Sinica, 2.0008, nanjing, PRC)

ＴＨＥＭＯＴＩＯＮＰＲＯＰＥＲＴＩＥＳＯＦＴＨＥＳＴＡＲＳＣＯＮＦＩＮＥＤＴＯＴＨＥＳＹＭＭＥＴＲＩＣＡＸＩＳＯＦＡＮＯＳＣＩＬＬＡＴＩＯＮＫＵＺＭＩＮＤＩＳＫＦｕＹａｎｎｉｎｇ１，２）ＳｕｎＹｉｓｕｉ１）（１）Ｄ... 详细信息

ＴＨＥＭＯＴＩＯＮＰＲＯＰＥＲＴＩＥＳＯＦＴＨＥＳＴＡＲＳＣＯＮＦＩＮＥＤＴＯＴＨＥＳＹＭＭＥＴＲＩＣＡＸＩＳＯＦＡＮＯＳＣＩＬＬＡＴＩＯＮＫＵＺＭＩＮＤＩＳＫＦｕＹａｎｎｉｎｇ１，２）ＳｕｎＹｉｓｕｉ１）（１）ＤｅｐａｒｔｍｅｎｔｏｆＡｓｔｒｏｎ...

关键词： celestial mechanics galactic dynamics galaxy oscillation

Solar Partial N-burst

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chinese Journal of Astronomy and Astrophysics 2003年第4期3卷 381-390页

作者： Zong-JunNing Yu-YingLiu Qi-Junfu fu-Yingxu NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012 purplemountainobservatory ChineseAcademyofSciencesNanjing210008

We present a new sub-class of type Ⅲ solar radio burst at the highfrequencies around 6.0 GHz. In addition to a descending and an ascending branch on the dynamicspectrum, it has an inverted morphology different from the simple type U-burst. We call it 'partialN-burst' because it is interpreted as the known N-burst minus its first branch. The partial N-burstpresented here was detected among a reverse slope type Ⅲ (RS-Ⅲ) burst group prior to the type Ⅴsolar radio continuum and was simultaneously recorded by two spectrometers at the NationalAstronomical Observatories, chinese academy of sciences (NAOC, 5.20-7.60 GHz) and at purple mountainobservatory (PMO, 4.50-7.50 GHz) on 1999 August 25. After the N-burst and M-burst, the partialN-burst is a third piece of evidence for a magnetic mirror effect in solar radio observation, whenthe same electron is reflected at a pinched foot of a flare loop.

关键词： sun: radio radiation sun: magnetic fields

Changes in overland flow and sediment during simulated rainfall events on cropland in hilly areas of the Sichuan Basin,china

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Progress in Natural Science:Materials International 2009年第11期19卷 1613-1618页

作者： Bin fu,Yukuan Wang~*,Pei xu,Daojie Wang Key Laboratory of mountain Hazards and Earth Surface Process,Institute of mountain Hazards and Environment, The chinese academy of sciences,Chengdu 610041,china [a]Key Laboratory of mountain Hazards and Earth Surface Process Institute of Mountain Hazards and Environment The Chinese Academy of Sciences Chengdu 610041 China

Water and soil loss are the major causes of the land degradation in the hilly area of the Sichuan Basin,china,where purple soil(FAO, Calcaric Regosols) is widely *** research has been conducted on changes in overland flow and sediment during rain events on sloping cropland in this *** this study,45 artificial rainfall events were applied to five runoff plots with slopes of 9%,18%,27%, 36%,and 47%,*** showed that erosion processes on purple soil of sloping cropland are complex,because the sediment concentration changes with time under different *** to correlations between runoff discharge and sediment concentration, all erosion events were classified into three types:(1) positive correlation;(2) negative correlation;and(3) no *** correlations were dominant,accounting for 60%of all *** intensity,slope gradient,and tillage treatment were the main factors that influenced erosion events.

关键词： Discharge-sediment concentration relationships Water erosion Artificial rainfall Hilly area of the Sichuan Basin purple soil

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星系振动的动力学研究进展

天文学进展 1998年第3期16卷 242-249页

作者：傅燕宁孙义燧南京大学天文系南京210093 中国科学院紫金山天文台南京210008

概括地介绍了盘星系的运动学边缘弯曲现象、盘星系中心的HI发射线空洞和棒旋星系中核球的长轴和棒的长轴不互相平行也不互相垂直等星系振动的问接观测证据；综述了星系振动动力学的理论研究情况，主要介绍了利用非静态维里方程和N体数... 详细信息

概括地介绍了盘星系的运动学边缘弯曲现象、盘星系中心的HI发射线空洞和棒旋星系中核球的长轴和棒的长轴不互相平行也不互相垂直等星系振动的问接观测证据；综述了星系振动动力学的理论研究情况，主要介绍了利用非静态维里方程和N体数值模拟得到的有关结果；展望了该领域今后的发展趋势，指出了建立引力自治的星系振动模型的必要性。

关键词：星系动力学天体力学星系振动

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不同施肥制度下紫色土坡耕地氮素流失特征

水土保持学报 2005年第5期19卷 65-68页

作者：汪涛朱波武永锋况福虹徐泰平中国科学院成都山地灾害与环境研究所西南农业大学资环学院重庆400716

利用野外径流小区试验,比较了川中紫色土丘陵区12种不同施肥制度下坡耕地侵蚀产沙特征和氮素迁移特征。结果表明,在单次降雨量达到44 mm时,相对于不施肥而言,农家肥配施化肥分别降低坡地径流与侵蚀量68.2%,67.3%,秸秆还田配施化肥分别降... 详细信息

利用野外径流小区试验,比较了川中紫色土丘陵区12种不同施肥制度下坡耕地侵蚀产沙特征和氮素迁移特征。结果表明,在单次降雨量达到44 mm时,相对于不施肥而言,农家肥配施化肥分别降低坡地径流与侵蚀量68.2%,67.3%,秸秆还田配施化肥分别降低80.3%,92.6%。不同施肥制度下随地表径流迁移的颗粒态氮占总氮的比例大部分都在60.0%以上。坡耕地平衡施肥能降低坡耕地土壤氮素随径流的损失,增施了磷、钾肥后,总氮迁移量分别降低了41.0%和46.1%。与不施肥相比较,农家肥配施化肥减少径流总氮69.0%,秸秆还田配施化肥减少90.5%。

关键词：施肥制度紫色土坡耕地氮素流失

1997年3月9日日全食8.6mm波段射电观测

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天体物理学报 1999年第1期19卷 97-103页

作者：吴洪敖周树荣查德元姚骑均许富英秦志海中国科学院紫金山天文台南京大学天文系

１９９７年３月９日日全食８．６ｍｍ波段射电观测资料的分析表明：８．６ｍｍ波段射电太阳的半径为１．０１２Ｒ，总流量为２５４０ｓｆｕ（１ｓｆｕ＝１０－２２Ｗ／ｍ２Ｈｚ），日面平均亮温度为９６３２Ｋ，径向亮温度分布，在日面... 详细信息

１９９７年３月９日日全食８．６ｍｍ波段射电观测资料的分析表明：８．６ｍｍ波段射电太阳的半径为１．０１２Ｒ，总流量为２５４０ｓｆｕ（１ｓｆｕ＝１０－２２Ｗ／ｍ２Ｈｚ），日面平均亮温度为９６３２Ｋ，径向亮温度分布，在日面光学边缘内侧０．９３６－０．９９２Ｒ处，存在临边增亮，平均增亮幅度相对于日面中心为９．７％．

关键词：日全食毫米波亮温度分布波段射电观测

The runoff characteristics under simulated rainfall on purple soil sloping cropland

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chinese Journal Of Geochemistry 2011年第3期30卷 317-322页

作者： xu Pei fu Bin Key Laboratory of mountain Surface Process and Hazards Chinese Academy of Sciences Chengdu 610041 China Institute of mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China

Rainfall runoff is a critical hydrological process related to soil erosion and agricultural non-point pollu-tion. In this study, 25 simulation experiments on rainfall were carried out in five runoff plots. Rape (Brassica campestris) was planted on the downslope of the plots. Experiments were conducted when the vegetation coverage reached 80%. Each plot was subjected to five rainfall events differing in intensity. The results showed: (1) the runoff coefficients of overland flow and subsurface flow were less than 0.6 and 0.005, respectively; (2) the discharge of overland flow was the quadratic function of time; (3) runoff coefficient was the function of slope gradient and rain-fall intensity. When the slope gradient increased from 8.7% to 46.6%, the runoff coefficient of overland flow first increased and then decreased. The runoff coefficient reached the maximum when the slope gradient was within the range of 17.6%-36.4%; and (4) the process of subsurface flow generation included the increasing phase and reces-sion phase. Discharge was a logarithm function of time in the increasing phase, and an exponential function in the recession phase. Runoff coefficient of subsurface flow decreased first and then increased when the slope gradient varied from 8.7% to 46.6% and was not correlated with rainfall intensity.

关键词：模拟降雨径流特性紫色土坡耕地农业非点源污染径流系数降雨强度径流小区

Assessment of the Performance of WEPP in purple Soil Area with Simulated Rainfall Experiments

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Journal of mountain Science 2012年第4期9卷 570-579页

作者： fu Bin WANG Yukuan xu Pei YAN Kun Key Laboratory of mountain Hazards and Earth Surface Process ChineseAcademy of SciencesChengdu 610041China Institute of mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China

The water erosion prediction project （WEPP） model is a popular water erosion prediction tool developed on the basis of the physical processes of water erosion. Although WEPP has been widely used around the world, its application in china is still insufficient. In this study, the performance of WEPP used to estimate the runoff and soil loss on purple soil （Calcaric Regosols in FAO taxonomy） sloping cropland was assessed with the data from runoff plots under simulated rainfall conditions. Based on measured soil properties, runoff and erosion parameters, namely effective hydraulic conductivity, inter-rill erodibility, rill erodibility, and critical shear stress were determined to be 2.68 mm h-1, 5.54 x l0^6 kg s-1 m-4, 0.027 s m-1 and 3-5 Pa, respectively, by using the recommended equations in the WEPP user manual. The simulated results were not good due to the low Nash efficiency of 0.41 for runoff and negative Nash efficiency for soil loss. After the four parameters were calibrated, WEPP performed better for soil loss prediction with a Nash efficiency of 0.76. The different results indicated that the equations recommended by WEPP to calculate parameters such as erodiblity and critical shear stress are not suitable for the purple soil areas, Sichuan Province, china. Although the predicted results can be accepted by optimizing the runoff and erosion parameters, more research related to the determination of erodibility and critical sheer stress must be conducted to improve the application of WEPP in the purple soil areas.

关键词： WEPP Soil erosion Simulated rainfall purple soil Erodibility