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261.
Justin B. France Maryam Haghighi Amy Watson Tessa Mills 《Journal of plant nutrition》2014,37(7):1056-1062
Information is scant on the mineral nutrition of plants undergoing partial rootzone drying (PRD). Researchers applied PRD to ‘Petopride’ tomato in a glasshouse by alternating irrigation to one side of the plant with half of the water in control (C). Roots in PRD treatment had higher magnesium (Mg) and copper (Cu) than C roots. Leaves in PRD treatment had lower P and higher K than C leaves. Minerals in leaves of C and PRD were within literature reported sufficiency ranges. Fruit of the PRD treatment had higher nitrogen (N) and zinc (Zn), but lower phosphorus (P), calcium (Ca), manganese (Mn) and boron (B) than C fruit. Mineral nutrition of fruit was most affected by PRD compared to that of leaf and root. Fruit of the PRD treatment had a higher incidence of blossom end rot (BER) than C fruit. Incidence of BER notwithstanding, although PRD affected the mineral nutrition of the tomato plant, there was no evidence that the lower yield in PRD was due to poor mineral nutrition. 相似文献
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263.
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
264.