Calculating soil moisture by remote sensing and analyzing hydrologic cycle process in the Yellow River basin

Based on the AVHRR pathfinder remote sensing data, soil moisture, precipitation and evaporation during the period of 1982–1998, soil moisture of all layers of soil-profile (0–1 m) in the Yellow River basin over the 17 years are calculated by the remote sensing model of calculating soil water. The Yellow River basin is divided into seven subcatchments as control sections at the location of six hydrologic stations (Lanzhou, Toudaoguai, Longmen, Sanmenxia, Huayuankou and Lijin). After calculating soil moisture and obtaining runoff data and precipitation data, the dynamical features of hydrological cycle in the Yellow River basin are analyzed for the period from 1982 to 1988 using water balance method. The conclusions are as follows: It is feasible to calculate the soil water on the macro-scale, in the soil profile with temporal continuity by means of remote sensing and survey in land. Some values of the key water cycle factors in the Yellow River are obtained, which include the annual precipitation of 4000 km³, the evapotranspiration of 3000–3500 km³, and the soil moisture transformation of −500–500 km³. Consequently, we analyzed the process of the water cycle in the Yellow River over the 17 years, and the results show that the segment upstream of Lanzhou city is a relatively humid region, and the area of internal waters and the reaches of Shanshan is the most desiccated region. Therefore, the runoff in the depth process is intensive and the runoff-generating process is weak in more arid regions.

     

Monitoring on soil erosion and sediment delivery at a typical basin of the middle and lower reaches of the Jialing River by remote sensing

The monitoring work was performed on soil erosion in Lizixi drainage arearespectively in 1986 and 1999 by multiple methods with the information extracted from theLandsat TM imagery and Spot imagery. The variation of erosion quantity in this area iscalculated based on the monitoring result of the erosion intensity and area in these twoyears. The change of sediment delivery is also analyzed. The research result shows thatcompared to 1986, in 1999, the erosion area reduced, especially for the area of moderateintensity and above, and the intensity and quantity of erosion decreased. Compared tothis period from 1965 to 1986, the sediment delivery ratio has been changed from 0.27 to0.11 after 1986. The research result could help the decision-making for further water andsoil conversation work in Lizixi drainage area, and it also offers reference for monitoring, evaluating and predicting soil erosion in other drainage areas.     

Web GIS design and realization for groundwater resources in the Yellow River basin

1PrefaceInthelastfewyears,thetechnologyofGeographicalInformationSystem(GIS)hasbeenwidelyusedandplayedagreatroleinthescientificresearchandproductionintheYellowRiverbasin.Uptonow,alotofdepartmentshavealreadydevelopedspecializedGISproductsorputforwardtherelevantdesignsofGISintheYellowRiverbasinfortheresearchofdifferentreachesanddifferentsubjectsofthisregion.TheCFCCfortheYellowRiverConservancyCommissionhasbuiltadatabasesys-temforthelowreachesoftheYellowRiverforthefloodpreventionin1991[1]…     

Study on the changes of water cycle and its impacts in the source region of the Yellow River

TheYellowRiveroriginatesfromtheQingnanPlateauofQinghaiProvince.Con-cerningitshydrological,geological,geomorphicandclimaticfeatures,severalwayscanbefoundtodefinethesourceregionoftheYellowRiver[1].Thesourceregionstudiedinthispaperisinthemostnarrowsense.Itliesinlatitude34°—35°15′northandlongi-tude95°40′—98°30′east[2—4].Thegaugedareais20930km2,averageprecipitation310mm,evaporationability1300—1600mm,andthealtitudeisabove4200m.Thisareaistypicalofaridplateauwithanaveragetemperatureof?4…     

黄河三角洲软土的特征及地基处理方法

通过整理大量的岩土工程、工程地质与水文地质勘察资料,总结了黄河三角洲地区软土的特征。同时论述了与软土层相伴生的无粘性土的地震液化性质。提出了该地区的地基处理方法。黄河三角洲60%的面积范围内发育软土层,软土层由近饱和或饱和的粘性土、淤泥及淤泥质粉土组成,属冲积与滨海～浅海沉积。该三角洲地区地基处理宜采用换土垫层、挤密桩、化学加固、桩基、箱基与箱桩等方法。     

基于遥感数据的宁夏地区土壤水分反演方法比较

利用MODIS产品数据MOD11A2和MOD13A2获取地表温度(TS)、昼夜温差(DST)、归一化植被指数(NDVI)、增强植被指数(EVI),构建宁夏区域2005年4、7、10月逢8、18、28日TS-NDVI、TS-EVI、DST-NDVI、DST-EVI特征空间,根据TS-NDVI、TS-EVI、DST-NDVI、DST-EVI特征空间建立了温度植被干旱指数(TV-DI)、温度增强植被指数型干旱指数(TE-DI)、温差植被干旱指数(DTVDI)、温差增强植被指数型干旱指数(DTEDI),并以这些干旱指数作为土壤水分监测指标,反演了宁夏区域2005年4、7、10月的土壤水分.利用实测10cm土壤水分进行相关分析,结果表明DTEDI在宁夏土壤水分反演中表现较好,DTVDI表现略好.     

土壤湿度的空间变异特征及尺度效应分析

基于遥感信息分析了土壤湿度的空间变异及尺度效应问题.利用多尺度遥感数据获得了归一化植被指数和地表温度,并基于此参数提取了干旱/半干旱地区的土壤湿度指数;基于分形理论,利用表面积计算方法,通过计算一系列不同尺度窗口像元的曲面面积,研究了三维曲面面积随尺度变化的规律,即定量描述了不同尺度遥感图像提取的土壤湿度指数值的变化特性,随着尺度的增加,驻点像元数减少,说明其空间异质性降低;并利用半变差函数研究了不同空间分辨率下土壤湿度的异质性特征.结果表明:空间分辨率越大,其整体空间异质性程度越小,与实际情况相符,说明利用分形几何学和地统计学方法分析土壤湿度指数的空间异质性特征是可行的.通过该研究可以有效地确定土壤湿度遥感监测的尺度,更好地了解区域尺度的土壤干旱程度及水资源情况.     

SMOS L2土壤水分数据产品在我国农区的验证

为了了解SMOS土壤水分数据产品对我国农区的作用,选取河南省4个站点(濮阳、卢氏、信阳、商丘),利用2011,2012年的4月、8月土壤水分实测数据和同期降雨数据,对SMOS L2土壤水分数据产品进行了验证分析。实验结果表明:针对我国的农耕地区,SMOS土壤水分反演值的干值偏差依然显著;受降水频次和强度的影响,其数值对湿季降水的响应要好于干季;而与实测值的相对和绝对差异亦显示,湿季两种土壤水分值的相关性优于干季;此外,通过站点间的比较,地理位置和土壤质地对其差异也存在一定影响。     

基于光谱学与遥感技术的矿区废弃地土壤特性参数分析

为了研究露天煤矿开采形成的废弃地对生态环境的影响,以阜新海州露天煤矿排土场作为研究对象,选取了36个采样点。首先测量了采样点土壤的反射光谱,然后在各点采集土壤样品并分析其特性参数。对36个采样点土壤样本的全氮、pH值、有机质和电导率等7个参数与光谱反射率进行相关性分析,得出:pH值与光谱反射率正相关,全氮、有机质、速效磷与反射率负相关;在600 nm红色波段之后pH值、有机质和全氮的相关系数较高;土样的速效氮、速效磷、速效钾及电导率与光谱反射率之间没有明显的相关性。在光谱分析基础上,利用SPOT5遥感影像相应波段灰度值建立了pH值、有机质、全氮等土壤参数的预测方程,获得了较高的精度。以上结果表明:可以用光谱反射率数据和遥感影像对废弃地土壤特征进行定量分析,为植被恢复提供决策数据。     

气候变暖下黄河源区冻土变化的数值模拟

近40年来,黄河源区地温长期处于增温状态,多年冻土出现表层融化。冻土退化后,土壤含水率减少,导致寒区径流的变化。所以研究冻土为寒区水资源估算提供了重要的依据。利用土壤水分迁移方程和热传导方程,采用中心差分格式并在一定假设前提下建立起冻土水热耦合迁移数学模型。对黄河源区站点的冻融深度进行模拟,结果表明：计算值和近2 a冻土的上、下限实测值吻合较好。由此表明采用的数学模型和数值方法是合理、可信的,在此基础上讨论了土壤冻融过程的一般规律。     

康熙时期黄淮水灾成因探析

康熙时期曾大规模地兴修黄淮水利,这是中国历史上一次浩大的人与自然的斗争,为“康乾盛世”繁盛局面的形成奠定了基础,这次大规模地兴修黄淮水利主要是因为当时水灾发生频繁。引发黄淮水灾的原因有两个方面：一是自然原因,二是社会原因 。通过对历史资料的分析和比较可以得出：人为活动所造成的破坏是引发水灾的主要原因。     

塔里木河流域遥感波段及重构向量的特征空间分析

遥感波段及其重构向量的特征空间研究是遥感模型构建的基础,针对塔里木河流域下垫面,研究了波段之间、Ts-NDVI、Ts-Albedo、Abedo-NDVI及植被指数之间在特征空间中的表征,并对其物理、生态学意义进行了分析.研究结果表明:某些特征空间中的点位分布存在一定的规律,这为地物信息提取提供可能,同时也为遥感技术更深一步研究提供借鉴.     

Efficiency of sediment transport by flood and its control in the Lower Yellow River

1IntroductionIntheriversystemwithsediment-ladenflow,WaterUseforSedimentTransport(WUST)isaveryimportantcomponentofecologicalwaterdemands,whichmaintainfundamentalfunctionofallecosystemcomponentsataspecificlevelofcondition[1].EnoughWUSTisthepremisetokeepthestableriver-bedandhealthyriverecosystem;alsoitisthebaseflowofriverfortheexploitationofwaterresources.Comparingwithotherrespectsrelatedwithwaterdemandsofriverecosystemsuchastheminimumflowforfishesorripariantrees,researchesontheWUSTarequite…     

基于遥感的黄河三角洲湿地时空变化特征及驱动因素研究

为适应黄河三角洲湿地快速频繁变化的特点并提高数据解释力度,为黄河三角洲科学规划和管理保护提供必要参考,基于Landsat影像密集观测1986—2021年15个时期的黄河三角洲湿地,研究湿地时空变化,定量分析驱动因素。结果表明:(1)黄河三角洲湿地存在波动变化和阶段性特征,自然湿地减少1 579.07 km²,滩涂和草甸灌丛损失率均超过60%;人工湿地面积增加了1 210.67 km²。(2)农田、建设用地和人工湿地扩张与自然湿地萎缩显著相关,相关系数分别为-0.682、-0.963、-0.976;2009年后因退耕还湿,开垦的影响减弱。(3)输沙量与自然湿地面积相关系数为0.614,在水文因素中起主导作用;1993年以前河口泥沙淤积效应强于海洋侵蚀作用,随后反转。(4)气温升高和干旱事件加剧了湿地损失。     

Study on thermal infrared remote sensing of Yarlung Zangbo River and Bangong Co-Nujiang River suture belt in Qinghai-Tibet Plateau

The area change of heat abnormity is not in accordance with conclusions of former thermal infrared remote sensing studies of the Qinghai-Tibet Plateau, which were that the temperature of Yarlung Zangbo River suture belt of the southern Plateau is high and the northern temperature is low. The study result in this paper shows that the highest temperature is found in the Bangong Co-Nujiang River suture belt, the Yarlung Zangbo River suture belt temperature is the second highest, and the northern Tibet temperature is the lowest. The study demonstration area was the suture belt areas of the Yarlung Zangbo River and the Bangong Co-Nujiang River in the Qinghai-Tibet Plateau, where the land temperature of the Qinghai-Tibet Plateau and the bore temperature of field land surface were measured and the emissivity of land surface was calculated. In addition, the authors explore the mechanism of the relationship between thermal infrared remote sensing and constructing thermodynamics and reach four new conclusions about the thermodynamics of the Tibet Plateau.     

关于黄河淤背区水土流失问题的探讨

黄河淤背区的存在 ,对确保黄河防洪安全有着重要意义 ,但淤区的水土流失现状堪忧 .通过对淤区水土流失成因、机理以及如何合理开发治理的分析探讨 ,提出了防治淤区水土流失的措施 .在发挥其防治效益的同时 ,也应重视开发种植效益 ,以改善黄河淤背区的生态环境     

安徽淮北地区墒情监测预报和抗旱决策信息系统研究

文章阐述了在安徽淮北地区建立墒情监测预报和抗旱信息系统的重要性,提出适用于淮北地区的土壤墒情监测方法和预报模型,对系统的情息传输、结构及功能作了较详细的介绍,在类似的干旱、半干旱地区均有参考和应用价值。     

普适型GPS用于黄河盐锅峡水位监测分析

黄河水文变化复杂,现有水位监测方法费时费力且不能很好满足时间分辨率和空间分辨率两个方面的需求.地基GPS-IR技术的出现为水位监测提供了新的手段,但目前大多数地基GPS-IR技术采用的接收机为高精度大地测量型接收机,成本高、时效性差,不适合大范围推广.首先介绍了普适型GPS接收机的组成,并对GPS数据观测质量进行了分析...     

黄河下游断流及其对策

黄河下游断流逐年加重,对国民经济产生不容忽视的影响。本文阐述了黄河发生断流的原因,并从节约用水、实施南水北调工程、利用现有水库调蓄水资源、制定切实可行的流域分水方案几个方面来探讨解决问题的措施。     

Basic research in the field of thermal infrared remote sensing

This overview paper points out that one of the problems impeding further development of remote sensing is that not much attention has been paid to basic research. Key contents of basic research in remote sensing, including modeling, inversion, scaling and scientific experiments, are reviewed. Significance of basic research is demonstrated through summarizing the intentions and progress of the project "Quantitative Remote Sensing Research on Land Surface Energy Exchange".