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61.
Review on estimation of evapotranspiration from remote sensing data: From empirical to numerical modeling approaches 总被引:5,自引:0,他引:5
Dominique Courault Bernard Seguin Albert Olioso 《Irrigation and Drainage Systems》2005,19(3-4):223-249
Different methods have been developed to estimate evapotranspiration from remote sensing data, from empirical approaches such
as the simplified relationship to complex methods based on remote sensing data assimilation along with SVAT models. The simplified
relationship has been applied from small spatial scale using airborne TIR images to continental scale with NOAA data. Assimilation
procedures often require remote sensing data over different spectral domains to retrieve input parameters which characterize
surface properties such as albedo, emissivity or Leaf Area Index. A brief review of these different approaches is presented,
with a discussion about the main physical bases and assumptions of various models. The paper reports also some examples and
results obtained over the experimental area of the Alpilles Reseda project, where various types of models have been applied
to estimate surface fluxes from remote sensing data. 相似文献
62.
R. Singh J.C. Refsgaard L. Yde G.H. Jørgensen M. Thorsen 《Irrigation and Drainage Systems》1997,11(3):185-213
A modelling system that combines the hydraulic simulations of the canal and hydrological simulations of the irrigated command is introduced. It uses MIKE 11 and MIKE SHE, two well-established modelling systems, for the hydraulic and hydrological simulations respectively. In addition, it also has an irrigation scheduling module and a crop growth module. The modelling system is applied to the Mahanadi Reservoir Irrigation Scheme, a large irrigation project in Central India. The results show that presently a significant amount of water is wasted in the command during the monsoon season. It is demonstrated that the minimization of this wastage could lead to a substantial crop production in the subsequent dry season. Furthermore, the simulations illustrate the versatility of the modelling system for planning and analysing the various aspects of an irrigation project. 相似文献
63.
我国植保机械及施药技术现状与发展趋势 总被引:10,自引:1,他引:10
阐述了我国植保机械及施药技术的现状,分析了我国施药技术中存在的问题以及与国外植保机械发展水平的差距,并提出了发展趋势。 相似文献
64.
Remotely sensed (RS) data is a major source to obtain spatialdata required for hydrological models. The challenge for thefuture is to obtain besides the more direct observable data(landcover, leaf area index, digital elevation model andevapotranspiration), non-visible data such as soilcharacteristics, groundwater depth and irrigation practices.In this study we have explore the option of using inversemodeling to obtain these non-RS-visible data. For a commandarea in Haryana, India, we applied for the 2000–2001 rabiseason a RS-GIS-combined inverse modeling approach to derivenon-RS-visible data required in the regional application ofhydrological models. A Genetic Algorithm loaded stochasticphysically based soil-water-atmosphere-plant model (SWAP) wasdeveloped for the inverse problem and used in the study. Theresults showed good agreement with the inventoried data suchas soil hydraulic properties, sowing dates, groundwaterdepths, irrigation practices and water quality. The deriveddata could be used to predict the state of the system at anytime in the cropping season, which can be used to evaluateoperational management strategies. 相似文献
65.
To facilitate weed suppression, oilseed rape or canola (Brassica napus) has been genetically modified (GM) over the last two decades to incorporate herbicide tolerance (HT). The introduction of oilseed rape in commercial agriculture raises concerns about potential adverse agronomic and environmental effects linked to both the genetic modification and altered agricultural practice. How will this new crop modify the existing cropping practice? What are the potential agro-environmental implications of its introduction? This paper analyses and schematises recorded and conceivable agricultural practice changes with GMHT oilseed rape introduction and its likely agro-environmental effects. It develops a conceptual systematics of influencing factors, subsequent practice changes and likely agro-environmental effects. The results can be used to design the mandatory monitoring of adverse GM crop effects. 相似文献
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67.
周振民 《中国农村水利水电》1992,(6)
该文以系统工程的原理方法,结合山东省陈垓引黄灌区北二干渠系统实际情况,分别以灌溉净效益最大和轮灌时间最短为目标,建立了作物最优种植面积和渠系优化配水模型,应用计算机求解,取得了满意的作物优化布局和优化配水成果。实践证明,本项成果在节水、灌溉增产、提高灌区科学管理水平等方面都有着十分重要的作用。 相似文献
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