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  

刘波  翟建青  高超  姜彤  王艳君 《地球科学进展》2010,25(9):974-980

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   

黑河流域日蒸散发遥感估算研究   总被引：6，自引：2，他引：4       下载免费PDF全文

李星敏-  卢玲  李新  杨文峰  黄春林  王钊 《高原气象》2010,29(1):109-114

地表蒸散的估算在干旱半干旱区水资源研究中具有重要意义。利用NOAA/AVHRR遥感资料、NCEP再分析格点资料和气象站点资料,根据能量平衡模型和FAO-17 Penman公式,计算了研究区域内逐日蒸散发量;对于晴天,用遥感模型反演出瞬时蒸散,进而推算出日蒸散;同时用FAO-17 Penmen公式和气象资料,计算研究区域内的同一天的蒸散,利用气象资料计算得到的蒸散与遥感估算的蒸散的关系,估算非晴空日的蒸散,进而得到逐日蒸散发结果。与同类研究结果的比较表明:该方法能够估算逐日蒸散发,通过气象与遥感资料结合,提高了气象格点资料的空间分辨率,弥补了难以得到遥感逐日晴空资料的不足,同时也为流域内同类研究提供参考依据。  相似文献   

Rainfall interception from a lowland tropical rainforest in Brunei   总被引：7，自引：0，他引：7  

A. P. Dykes 《Journal of Hydrology》1997,200(1-4):260-279

Results from a programme of throughfall measurements in a lowland tropical rainforest in Brunei, northwest Borneo, indicate that interception losses amount to 18% of the gross incident rainfall. The high annual rainfall experienced by the study area results in annual interception losses of around 800 mm, which may result in total annual evapotranspiration losses significantly higher than in other rainforest locations. An improved version of Gash's analytical interception model is tested on the available data using assumed values for the “forest” parameters, and is found to predict interception losses extremely well. The model predictions are based on an estimated evaporation rate during rainfall of 0.71 mm h⁻¹. This is significantly higher than has been reported in other tropical studies. It is concluded that these results are distinctive when compared with previous results from rainforests, and that further, detailed work is required to establish whether the enhanced evaporation rate is due to advective effects associated with the maritime setting of the study area.  相似文献   

极端干旱区柽柳林地蒸散量及能量平衡分析   总被引：2，自引：4，他引：2  

司建华  冯起  席海洋  常宗强 《干旱区地理》2006,29(4):517-522

运用波文比-能量平衡法对极端干旱区柽柳林地的蒸散量及能量通量进行了连续的测定和估算,并对柽柳林地蒸散特点和能量平衡进行了分析和探讨。结果表明:柽柳林地的日平均蒸散量为1.6 mm/d,整个生长季的蒸散量为248.2 mm,蒸散量的季节变化系数为47%±3%。柽柳林地蒸散量的季节变化与土壤水分条件密切相关。柽柳林地蒸散量受气象因子和下垫面条件的影响和制约。在极端干旱区,感热通量消耗了绝大多数的能量,潜热通量在整个生长季只占很小的一部分,夜间,土壤储存的能量是大气能量的主要来源,而白天土壤是能量的主要汇源。  相似文献   

Water balance of a tropical woodland ecosystem, Northern Australia: a combination of micro-meteorological, soil physical and groundwater chemical approaches     

P. G. Cook  T. J. Hatton  D. Pidsley  A. L. Herczeg  A. Held  A. O''Grady  D. Eamus 《Journal of Hydrology》1998,210(1-4):161-177

A combination of micro-meteorological, soil physical and groundwater chemical methods enabled the water balance of a tropical eucalypt savanna ecosystem in Northern Australia to be estimated. Heat pulse and eddy correlation were used to determine overstory and total evapotranspiration, respectively. Measurements of soil water content, matric suction and water table variations were used to determine changes in soil moisture storage throughout the year. Groundwater dating with chlorofluorocarbons was used to estimate net groundwater recharge rates, and stream gauging was used to determine surface runoff. The wet season rainfall of 1585 mm is distributed as: evapotranspiration 810 mm, surface runoff (and shallow subsurface flow) into the river 410 mm, groundwater recharge 200 mm and increase in soil store 165 mm. Of the groundwater recharge, 160 mm enters the stream as baseflow in the wet season, 20 mm enters as baseflow in the dry season, and the balance (20 mm) is distributed to and used by minor vegetation types within the catchment or discharges to the sea. In the dry season, an evapotranspiration of 300 mm comprises 135 mm rainfall and 165 mm from the soil store. Because of the inherent errors of the different techniques, the water balance surplus (estimated at 20 mm) cannot be clearly distinguished from zero. It may also be as much as 140 mm. To our knowledge, this is the first time that such diverse methods have been combined to estimate all components of a catchment's water balance.  相似文献   

不同地表覆盖条件下区域水分盈亏的遥感分析——以中国北方为例   总被引：9，自引：0，他引：9  

陈云浩  李晓兵  李霞  高清竹  谢锋 《地球科学进展》2002,17(2):283-288

依据能量平衡和水分平衡原理，建立不同地表覆盖条件下的区域缺水计算方法，实现了利用遥感数据对我国北方缺水状况的宏观监测和快速反应。模型的具体步骤是：首先，利用NOAA/AVHRR数字影像进行地表覆盖分类，结合气象数据建立区域实际蒸散模型，并利用经联合国粮农组织修正的Penman公式计算区域潜在蒸散量。然后，由区域实际蒸散量和潜在蒸散量，构造出反映区域缺水程度的缺水指数。最后，利用该方法对1999年7月我国北方的区域水分盈亏状况进行了研究，讨论了区域缺水指数与土壤墒情、背景环境参数、地表覆盖类型的关系。  相似文献   

World patterns and amounts of detrital soil carbon     

Vernon Meentemeyer  John Gardner  Elgene O. Box 《地球表面变化过程与地形》1985,10(6):557-567

Soil carbon data were collected from published sources for 50 measurement sites spanning the globe's major climate and vegetation types. For each site, climate, vegetation, and land-use variables were determined and entered into a multiple curvilinear regression program to predict soil carbon. The best model incorporates an estimate of site disturbance, annual actual evapotranspiration, and annual soil moisture deficit, and yields an R = 0-803. The curvilinear regression equation was coupled with a large climatic database and computer cartography programs to produce first-generation maps of estimated soil carbon. These maps correctly portray soil carbon as high in boreal and cool temperate zones and low in deserts and tropical zones. Computer planimetry of maps of soil carbon for an ‘undisturbed’ world and for a ‘disturbed’ world resulted in estimates of 1457 × 10⁹ mtC and 504 × 10⁹ mtC respectively. These estimates compare favourably with recent estimates using other approaches. Clearly, the disturbance factor is critical to future refinements in estimates, suggesting the need for detailed studies of the relationship between land-use history and the creation and destruction of this important carbon pool.  相似文献   

大型称重式蒸渗计的研制   总被引：11，自引：1，他引：11       下载免费PDF全文

柯晓新  林日暖 《应用气象学报》1994,5(2):151-157

介绍了安装在兰州干旱气象研究所定西综合试验站的大型称重式蒸渗计，它的有效蒸散面积4.0m2,原状土柱深约2.6m,测试精度0.1mm,是我国气象部门研制的第一台大型称重式蒸渗计。  相似文献   

A model for heat and water balance estimation and its application to land use and climate variation     

Janusz Olejnik  Andrzej Kedziora 《地球表面变化过程与地形》1991,16(7):601-617

This paper presents a method, which has been recently developed in the Department of Agrometeorology of the Poznań Agricultural University, for estimating heat balance components based on standard meteorological data, plant development stage, and land-use conditions. Estimates of latent heat flux components made it possible to obtain values of areal evapotranspiration and surface runoff. The method was applied in four catchment areas in Central Poland under present climatic conditions as well as under new, expected climatic conditions caused by an increase of ‘greenhouse gases’ in the atmosphere. Some changes in land use were also considered. The results show significant changes in the water balance when comparing present and future conditions of precipitation and evapotranspiration.  相似文献   

应用MODIS数据推估区域地表蒸散   总被引：4，自引：1，他引：3       下载免费PDF全文

刘朝顺  高炜  高志强 《水科学进展》2009,20(6):782-788

通过"热增强"方法,充分利用MODIS数据的时间分辨率和空间分辨率的优势,基于对SEBAL模型改进的基础上,反演并验证了山东省的地表蒸散。结果表明,蒸散反演结果与实测值具有很好的一致性,日平均相对误差约为-11.34%。同时分析了研究区2005年和2006年不同土地利用/覆盖类型下蒸散的逐月变化规律,发现水域的月平均蒸散量最大,其次为水田,林地、旱田和草地基本相当,人工用地的月平均蒸散量最小。  相似文献