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261.
Simulation of 1D surface and 2D subsurface water flow and nitrate transport in alternate and conventional furrow fertigation 总被引:3,自引:0,他引:3
Hamed Ebrahimian Abdolmajid Liaghat Masoud Parsinejad Enrique Playán Fariborz Abbasi Maryam Navabian 《Irrigation Science》2013,31(3):301-316
Increasing water and fertilizer productivity stands as a relevant challenge for sustainable agriculture. Alternate furrow irrigation and surface fertigation have long been identified as water and fertilizer conserving techniques in agricultural lands. The objective of this study was to simulate water flow and fertilizer transport in the soil surface and in the soil profile for variable and fixed alternate furrow fertigation and for conventional furrow fertigation. An experimental data set was used to calibrate and validate two simulation models: a 1D surface fertigation model and the 2D subsurface water and solute transfer model HYDRUS-2D. Both models were combined to simulate the fertigation process in furrow irrigation. The surface fertigation model could successfully simulate runoff discharge and nitrate concentration for all irrigation treatments. Six soil hydraulic and solute transport parameters were inversely estimated using the Levenberg–Marquardt optimization technique. The outcome of this process calibrated HYDRUS-2D to the observed field data. HYDRUS-2D was run in validation mode, simulating water content and nitrate concentration in the soil profiles of the wet furrows, ridges and dry furrows at the upstream, middle and downstream parts of the experimental field. This model produced adequate agreement between measured and predicted soil water content and nitrate concentration. The combined model stands as a valuable tool to better design and manage fertigation in alternate and conventional furrow irrigation. 相似文献
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玛丽帕·吐达洪 阿不都外力·阿布都热依木 孜来古丽·米吉提 卡依尔·玉素甫 马丽艳木·阿木东 艾尼江·尔斯曼 祖母拉提·阿布都热依木 艾尔肯·热合曼 《干旱区研究》2011,28(6):1071-1080
以西昆仑山2个海拔样点的土样为对象,利用(LB和TSA)2种培养基,基于16S rRNA基因序列的系统发育,采用纯培养法对其可培养细菌多样性进行研究。2样点中共分离到91株细菌,分为25个属,52个种。厚壁菌门(Firmicutes)占总菌数的48.75%,放线菌门(Actinobacteria)占36.25%,γ-变... 相似文献
264.
Maryam MOSLEHI JOUYBARI Asgahr BIJANI Hossien PARVARESH Ross SHACKLETON Akram AHMADI 《干旱区科学》2022,14(10):1099-1108
Biological invasions can alter soil properties within the range of their introduced, leading to impacts on ecosystem services, ecosystem functions, and biodiversity. To better understand the impacts of biological invasions on soil, we compared topsoil physiochemical properties at sites with invasive alien tree species(Prosopis juliflora), native tree species(Prosopis cineraria, Acacia tortilis, and Acacia ehrenbergiana), and mixed tree species in Hormozgan Province of Iran in May 2018. In this s... 相似文献