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Gholamhassan Ranjbar; Farhad Dehghani; Arash AlaEddin; Vali Soltani Gerdfaramarzi; Sardar Keshtkar
Abstract
Lack of fresh water resources has led to production of salt tolerant species. This study was conducted in 2019-2020 to investigate the effect of irrigation water salinity on forage yield, plant height, and shoot ash content of Salicornia bigelovii and native Salicornia ecotypes including Bushehr (S. ...
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Lack of fresh water resources has led to production of salt tolerant species. This study was conducted in 2019-2020 to investigate the effect of irrigation water salinity on forage yield, plant height, and shoot ash content of Salicornia bigelovii and native Salicornia ecotypes including Bushehr (S. sinus persica), Central Plateau, Gorgan and Urmia of S. persica under irrigation with Persian Gulf (60 dS m-1) and groundwater (20 dS m-1), in Bushehr and Yazd conditions, respectively. Results showed that there were significant differences between the species and ecotypes in terms of fresh and dry weight of forage in both conditions. The highest fresh and dry weight of forage were related to Bushehr ecotype in both conditions, but the lowest of these traits were in S. bigelovii in Yazd and in Gorgan and Urmia ecotypes in Bushehr conditions. The amount of fresh forage for Bushehr ecotype were about 9333 and 22940 g m-2 in Bushehr and Yazd, respectively. In general, plant height under seawater irrigation conditions varied from 23.0 cm to 35.5 cm in Bushehr condition, and 56.5-78.0 cm in Yazd condition under saline groundwater. Regardless of species and ecotypes, the average shoot ash content in Bushehr and Yazd conditions were, respectively, 53.83% and 47.76%. Based on the results of the study, Bushehr ecotype could be considered as superior for planting and forage production in the southern coastal strip. In Yazd condition, due to better water quality, all species and ecotypes produced high fodder yield. However, due to high water requirement of Salicornia, its production in arid areas, especially in the central regions of the country, is not recommended.
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Hossein Beyrami; Mohammad Hassan Rahimian; Farhad Dehghany
Abstract
Water and soil resources of the country are limited, and the optimal use of water resources in agriculture requires estimation of the exact amount of water consumption by different plants in different conditions. This study was conducted to investigate evapotranspiration, crop coefficient, and water ...
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Water and soil resources of the country are limited, and the optimal use of water resources in agriculture requires estimation of the exact amount of water consumption by different plants in different conditions. This study was conducted to investigate evapotranspiration, crop coefficient, and water requirements of salicornia under lysimetric conditions in a factorial experiment with completely randomized design. The experimental treatments were two species of salicornia (Salicornia bigelovii and Salicornia persica) and two levels of irrigation water salinities (8 and 25 dS.m-1) in three replications. The actual evapotranspiration (ETa), reference evapotranspiration (ET0), and crop coefficients (Kc) of salicornia species were determined at three main salicornia growth stages. The results showed that increase in irrigation water salinity from 8 to 25 dS.m-1caused significant changes in yield (biomass and seed yield) of the two salicornia species at the 1-percent probability level. Moreover, the amount of irrigation water consumption in different treatments and replications varied from 28 to 33 thousand cubic meters per hectare. For the salinity level of 8 dS.m-1, the Kc values at the beginning, middle, and end of growing season of bigelovii specie were obtained as 1.18, 1.55, and 1.42, respectively, while for the salinity level of 25 dS.m-1, these values were 1.06, 1.37, and 1.26, respectively. For persica specie, the Kc values of the beginning, middle, and end of the growing season were 1.37, 1.58, and 1.10 (for salinity level of 8 dS.m-1) and 1.15, 1.38 and 1.27 (for salinity level of 25 dS.m-1), respectively. In addition, water use efficiencies of salicornia varied from 0.21 to 0.38 kg.m-3 at different treatments and species.
f dehghani; r r; m.j malakouti; saeed saadat
Abstract
Calcium and magnesium ions are two plant nutrients and are omnipresent in all natural systems. Calcium to magnesium ratio (Ca:Mg) is an important factor in evaluation of water quality for irrigation. A Ca: Mg ratio of less than unity, in particular in saline condition, adversely affects soil physico-chemical ...
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Calcium and magnesium ions are two plant nutrients and are omnipresent in all natural systems. Calcium to magnesium ratio (Ca:Mg) is an important factor in evaluation of water quality for irrigation. A Ca: Mg ratio of less than unity, in particular in saline condition, adversely affects soil physico-chemical characteristics, and could decrease plant yield through nutritional imbalance. Frequent drought and groundwater over-draft have lowered groundwater level and its quality severely, including increase in salinity and, in many cases, relative increase in magnesium ion concentration. In order to assess distribution and changes in Ca:Mg ratio, laboratory analysis data of more than 6200 irrigation water samples were collected from 11 provinces. Data analysis revealed that Ca:Mg ratio was less than unity in about 55% of the samples. It was also found that increase in salinity had a significant correlation with Ca and Mg ions concentrations, but had no relation with their ratio. Correlation analysis indicated that maximum correlation was between Na ion concentration and salinity (R2= 0.86), and 60% of Ca and Mg variation could be explained with variation in salinity. However, no significant relation was found between salinity and Ca:Mg ratio. Using such irrigation water gradually increases exchangeable Mg ion and decreases soil quality (degradation of soil structure and lowering infiltration rate), and causes plant nutritional disorder. Consequently, more detailed assessment of these waters and their effects on soil and plant is enormously important from both economic and environmental points of view.