Showing 64 results for Salinity
M. Shamsaddin Saied, H. Farahbakhsh, A. A Maghsoodi Mude,
Volume 11, Issue 41 (10-2007)
Abstract
In order to study the effects of salinity on germination, vegetative growth and some physiological characteristics of canola cultivars, two experiments were conducted at Research Station of Agricultural College of University of Kerman in 2004. The experimental design was a Completely Randomized Block with four replications. Treatments comprised all combinations of different levels of three factors including variety (Kobra × Regent, Ceres and Okapi), salt type (NaCl, CaCl2) and electrical conductivity of saline solution (0, 4, 8, 12 dS/m). Results of variance analysis showed that salinity has a very significant effect on germination percentage, germination homogeneity, germination rate, rootlet and polomul length at the end of the germination stage. Shoot length, dry weight, diameter and number of nodes per shoot were significantly affected also by salinity at vegetative growth. Regarding the two types of salt, none of the measured traits were significantly different. All the mentioned traits decreased with increasing salinity the highest and the lowest values were recorded at control and at 12 dS/m salinity levels. Membrane ion leakage was the only trait which increased significantly. Comparison of means showed germination percentage and germination homogeneity at germination stage and the number of nodes at vegetative growth stage were affected less than other traits by salinity, and they only decreased significantly with increasing salinity to 12dS/m. The effect of cultivar on these traits was also significant (P<0.001). In both growth stages, cultivars response to salinity was different. At germination stage, Ceres and Kobra * Regent cultivars were the most sensitive and tolerant ones in terms of all traits and there was no significant difference between Okapi and Kobra *Regent. At vegetative growth stage, however, Okapi showed less growth than Kobra * Regent and their difference was significant. It seems that evaluation of traits response at germination stage can not be effective to determine salt tolerance of canola cultivars.
M. Soltani Huwyzeh, S.a.m. Mirmohammady Maibody , A. Arzani,
Volume 11, Issue 42 (1-2008)
Abstract
Sugarcane is one of the most important sugar crops in the world. Because of semi-arid climate and salinity of its cultivation area in our country, increasing salt tolerance of sugarcane is signifying. To achieve this goal determining salt tolerant cultivars and understanding salinity mechanisms in sugarcane are very important. This study was conducted to evaluate 8 commercial and promising sugarcane cultivars at early stage of growth. A complete randomized design with three replicates and four salinity treatments (0, 0.25, 0.5, 0.75 % NaCl) was used in a hydroponics system. The effect of salinity on absorption, transport and accumulation of Na+, Cl- , K+ and Ca2+ ions in shoot and root was determined. At high level salt concentration, Cl- content in shoot and root increased. Result showed that sodium accumulation in sugarcane plants was more than potassium. By increasing salinity level, sodium uptake and its translocation to shoots increased reducing growth and dry matter yield of plants. With rising salt concentration from medium (0.5%) to high (0.75%), content of chloride in shoot and root of NCO-310 was constant showed that this cultivar had genetic ability to avoid Cl- uptake. CP82-1592 with lowest ratio of shoot / root chloride had minimum transport of Cl- to shoots. Also this cultivar had high content of Ca2+ in shoot and low Na+/Ca2+ ratio at all salinity levels. CP48-103 had low sodium in shoot and relatively low sodium in root. Thus it probably has genetic potential to avoid sodium uptake. At last, exclusion of Na+ and Cl- to older leaves and tillers was seen in CP82-1592 and CP72-2086 cultivars. According to results, to avoid once of absorption and transport, and exclusion of harmful Na+ and Cl- ions were mechanisms that could be used in salinity tolerance of sugarcane.
M. Naderi Khorasgani, A. Karimi,
Volume 11, Issue 42 (1-2008)
Abstract
This research was carried out to study the impacts of geomorphologic characteristics of claypan on land use and land degradation. Databank of the study area was constructed and digital terrain model of claypan was prepared. By using GIS techniques spatial distributions of the subsurface drainage network, sediment transportation index and wetness index were calculated. The results indicate that the depth to the claypan is between 0 (where the pan is exposed at the surface) to 605 cm. There are several depressions in the claypan which are filled by new sediments. Each depression has a catchment which is charged by the drainage water of its attributed lands. While a depression drains naturally or synthetically, the attributed soils over the depression are in non saline or moderate salinity condition otherwise, a marshland, a waterlogging area or a salt crust zone develops over there. The results also indicated that soil surface salinity is a function of depth to claypan and drainage condition of area. The trends of salinity extension are different for closed and open catchments and the depth to the claypan could be estimated using electrical conductivity. The results also show that analysis of microtopography of soil surface and soil stratification should be considered for designing irrigation and drainage networks.
A. Mohammadi Mohammadabadi, S.j. Hosseinifard, N. Sedaghati,
Volume 12, Issue 43 (4-2008)
Abstract
Effect of change from the conventional (flooding) to subsurface irrigation system was studied on mature pistachio trees (Cultivar Ohadi) in Kerman pistachio research station for four years. This experiment was carried out in a randomized complete block design including 7 treatments and 3 replications. The experiment also used two irrigation intervals (7&14 days) and three water rates according to pan coefficient (20%, 40%& 60% evaporation from surface of class A pan) for subsurface irrigation system with 6 treatments the conventional (flooding) irrigation system was tested as control. The pipes of subsurface irrigation system were installed at 90cm distance from trees trunk at each side of trees, and 50cm from soil surface. Mean of pressure and discharge in the pipes was 0.8 to 1 atmosphere and 5.4 Lh-1m-1, respectively. Different factors of quantity and quality pistachio yield, current vegetative growth, water use efficiency and soil electrical conductivity were measured. The results showed that change of conventional (flooding) to subsurface irrigation system is possible and the best treatment can have water rate of 7174 m3ha-1y-1 with 14 days irrigation interval. In comparison with other treatments, this treatment has better quantity and quality pistachio yield. Water use efficiency (WUE) of this treatment was 164g dry yield per cubic meter. Nevertheless, application of water rate of 4783 m3ha-1y-1 can result in the deficiency of irrigation water. At this water rate, WUE was 177g dry yield per cubic meter. However, it was found that the application of lower water rate (<4783 m3ha-1y-1) produced severe effects on the treated pistachio trees, e.g. decreasing the growth rate, yield and increasing the early splitting in pistachio fruits. Finally, it is concluded that 14-day interval irrigation is the preferred treatment for pistachio trees. Also, soil salinity showed considerable change in subsurface irrigation treatments after irrigation system was changed, especially in the first year.
M. Shamseddin, H. Farahbakhsh ,
Volume 12, Issue 43 (4-2008)
Abstract
To study the effect of salt stress on quantitative and qualitative parameters of canola (Brassica napuse. L) cultivars, and determine the possible mechanisms of salt tolerance and the best salt tolerance indices, an experiment was conducted under a rain-shelter at experimental field of university of Kerman in 2004. The experimental design was a complete randomized block (RCOD) with four replications. Treatments consisted of all combinations of different levels of three factors including variety (Kobra×Regent, Ceres and Okapi), salt types (NaCl and CaCl2) and electrical conductivity of saline solution (0, 4, 8 and 12 dS/m). All treatments were randomly distributed in each replication. Results of the analysis of variance showed that grain yield, yield components, oil and protein contents were significantly affected by salinity (P< 0.001). All the mentioned traits reduced with increasing salinity. It was also found that there were significant differences among genotypes for the mentioned traits. Cultivar of Kobra×Regent showed the highest values of the above traits except for the oil content. Proline, protein and sugar contents were also affected significantly by salinity (P<0.001). The highest and lowest sugar concentrations and protein contents were recorded for control and 12dS/m treatments, respectively. Proline content showed a reverse response and increased with increasing salinity. Mean productivity (MP), geometric mean productivity (GMP) and stress tolerance index (STI) are suggested to be the most suitable indices in order to select genotypes of high productivity under both stress and normal conditions. Based on these results, Kobra*Regent was selected as the most tolerant cultivar.
N. R. Jalali, M. Homaee, S. Kh. Mirnia,
Volume 12, Issue 44 (7-2008)
Abstract
Canola (Brassica napus L.) in response to salinity represents various resistances with respect to its phonologic stages. Most plants such as Canola are resistant at germination stage. However, at seedling or earlier growth stages, plants become more sensitive to salinity but their tolerance increases with age. Salt tolerance of various plants has been extensively studied however, the results have either been qualitative or expressed as average values over root zone salinity for the whole growth season. Thus, developing appropriate models for quantitative characterization of plant response to salinity at different growth stages is essential. Canola which is considered as high economic value plant was selected for this study. Two productive stages for canola are recognized as flowering and ripening. To determine the effect of salinity on canola at vegetative growth stages, a greenhouse experiment was conducted on a natural saline loamy sand soil, using salinity treatment including one non-saline water (tap water) and 8 saline waters of 3 to 17 dS.m-1. The canola plants were irrigated with tap water before the desired stage and then salinity treatments were imposed. The Maas and Hoffman (1977), van Genuchten and Hoffman (1984), Dirksen et al., (1993), and Homaee et al., (2002b) models were used to predict relative transpiration (Ta/Tp ) and relative yield ( Y/Ym) as a function of soil salinity. The maximum error (ME), root mean square error (RMSE), coefficient of determination (CD), modeling efficiency (EF) and coefficient of residual mass (CRM) statistics were calculated to compare the models and their efficiencies. The results indicated that the van Genuchten and Hoffman (1984) model provides best prediction at flowering stage. However the Homaee et al. (2002b) model offers better prediction at ripening growth stage.
M. Hajghani, M. Saffari, A. A. Maghsoudi Moud,
Volume 12, Issue 45 (10-2008)
Abstract
Soil salinity is an increasing environmental stress on crops in most areas of Iran since farmers use underground saline water for irrigation. In order to investigate the effects of salt stress on germination and seedling growth of safflower (Carthamus tinctorius L.), an experiment was conducted at two stages (germination seedling growth), using four levels of NaCl salinity (0, 5, 10, 15 ds/m), and four cultivars of spiny and non-spiny safflower ( a landrace from Isfahan bred cultivars of IL, LRV and PI). The design was factorial and completely randomized based on 3- replicates (CRD). Germination percentage, germination velocity index, root and shoot length, root and shoot dry weight, root to shoot dry weight ratio and salt tolerance index were measured at germination stage. In seedling growth stage, traits such as, stem length, number of leaves, chlorophyll index, root and shoot dry weight, root to shoot dry weight ratio and salt tolerance index were also measured. Results for both growth stages showed that salt stress decreased all the above mentioned traits, significantly, in all cultivars. Salinity × variety interaction at germination stage was also significant, compared to seedling growth stage. Salt tolerance index decreased significantly with increasing salinity at both stages, but differences between cultivars were not significant. Cultivars PI and IL were characterized as the tolerant ones at germination and seedling growth stages, respectively. It could be concluded that safflower cultivars responded differently to salinity in germination phase compared to seedling growth phase, and that safflower suffers more from salinity during germination stage.
Y Hosseini, M Homaee, N Karimian, S Saadat,
Volume 12, Issue 46 (1-2009)
Abstract
Modeling plant response to salinity and nitrogen deficiency is very important for estimating optimum yield in arid and semi-arid regions. For this purpose, the models of Leibig-Sprengel (LS) and Mitscherlich-Baule (MB) originally proposed to explain plant response to nutrients only were modified to evaluate plant yield response to combined nitrogen and salinity stress conditions. Afterwards, in order to model canola (Brassica napus L.) response to combined salinity and nitrogen stress, an experiment was designed with different nitrogen and salinity levels. The water salinity treatments consisted of non-saline water, 3, 6, 9 and 12 dS m-1. The nitrogen treatments were 0, 75, 150 and 300 mg kg soil-1 added as ammonium nitrate. The results indicated that both modified models can satisfactorily predict canola yield. However, the modified MB model (R2=0.94) provided better estimation than the modified LS model (R2=0.87). The calculated statistics including Maximum Error, Root Mean Square Error, Modeling Efficiency, Coefficient of Determination and Coefficient of Residual Mass for the modified models indicated that the estimated relative grain yield for soil nitrogen, salinity and each rate of soil nitrogen in salinity levels by modified MB model compared with those by modified LS model is closer to the measured relative yield. Therefore, the use of modified MB model for estimating canola relative grain yield in salinity and nitrogen stresses is recommended. Using modified LS model showed that the salinity threshold value changes with the applied nitrogen. In this case, by application of each 75 mgN kg-1 soil, the salinity threshold value decreased 4 dS m-1 in saline conditions. Application of nitrogen decreased chloride concentration in grains under saline conditions. Nitrogen uptake also augmented with increasing canola transpiration, because nitrogen was carried over from soil to the uptake sites mainly by mass flow.
S Bazi, M Haydari, N Mehdinejad, F Abasi,
Volume 12, Issue 46 (1-2009)
Abstract
To evaluate effects of different salinity levels on activity of antioxidant enzymes (CAT, APX and GPX) and osmotic components (carbohydrate and proline) in two sorghum genotypes, an experiment was conducted as completely randomized factorial design with three replications in Zabol university in 2007. Three levels of salinity control (0), 100 and 200 mM NaCl and two sorghum genotypes (Payam and Sistan) were compared. Results showed that by increasing salinity levels from 0 to 200 mM NaCl, the activities of these three antioxidant enzymes were significantly increased and the highest level of activity was observed in 200 mM salinity. Payam cultivar had the highest level of APX and GPX enzyme activity in these experiments. salinity significantly changed two osmotic adjustment concentrations (Carbohydrate and proline) and increased their concentrations. The highest proline and carbohydrate were showN in Sistan and Payam, respectively. In this study we found positive correlation between osmotic components and antioxidant enzyme activity. The results showed that in these two sorghum cultivars the two mechanisms help with salinity tolerance. A direct relationship between activity of the antioxidant- enzymes and accumulation of osmotic regulators (carbohydrate and proline) was observed. In Payam genotype, as the activity of the enzymes and accumulation of osmotic regulators increased, the weight of the plants decreased. The decrease in weight could mean some of plant energy is allocated to the production of antioxidant enzymes and osmotic regulators.
B Salari, M Shamsedin Said, A Askarian Sardari,
Volume 12, Issue 46 (1-2009)
Abstract
In order to study the effect of NaCl priming on some agronomical and physiological traits of corn (single cross 704), an experiment was conducted at Agricultural Research Station of Bahonar University of Kerman in 2005. The experimental design was completely randomized designs with 3 replications. Treatments were a combination of all different levels of two factors including salinity levels (1, 4, 8, 12, 16 dS/m) and salinity solution for NaCl priming (1, 4, 8, 12, 16 dS/m). Results showed that salinity and NaCl priming had significant effects on total emergence, mean time to emergence, root and stem length, number of leaf, relative water content, ion leakage and K+/Na+. Mean comparison showed that increasing salinity decreased all plant characteristics (with the exception of mean time to emergence and ion leakage) by %49.5, %33.49, %23.97, %18.64, %14.05 and %40.20, respectively. However, increasing salinity led to 1.2 and 1.3 increase in mean time to emergence and ion leakage of leaves, respectively. Mean comparison also showed that NaCl priming decreased negative effects of salt stress, and all mentioned traits under NaCl priming increased as compared with control. The results showed that NaCl priming is a useful method for increasing salt tolerance in corn plant.
A Razavinasab, A Tajabadi, H Shirani, H Dashti,
Volume 13, Issue 47 (4-2009)
Abstract
To study the effect of nitrogen, salinity and organic matter on growth and root morphology of pistachio (Cv. Badami), a greenhouse experiment was conducted. Treatments consisted of four nitrogen (N) levels (0, 60, 120 and 180 mg kg-1 soil as urea), four salinity levels (0, 800, 1600 and 2400 mg NaCl kg-1 soil) and three organic matter (OM) levels (0, 2 and 4% soil as farmyard manure). Treatments were arranged in a factorial manner in a completely randomized design with three replications. As the salinity levels increased, leaf, stem and root dry weights and root density, were significantly reduced. Addition of N up to 120 mg kg-1 soil, had no significant effect on growth, but the highest N level (180 mg kg-1), due to nutrient imbalance, reduced abovementioned plant parameters. In low salinity levels, N application improved the growth of pistachio seedlings, but at the highest salinity level, N addition didn’t suppress the adverse effects of soil salinity. Due to useful physical and nutritional properties of soil organic matter, addition of OM significantly increased leaf, stem and root dry weights, stem height, shoot/root ratio and root density.
M Eskandari Torbaghan, A.l Astaraei, M Eskandari Torbaghan , A Ganjali,
Volume 13, Issue 50 (1-2010)
Abstract
Chlorine and sulfate toxicity in water and soils are the main factors limiting growth and yield of most plants. Tolerance and sensitive indexes related to Cl and SO4 in irrigation water and effect of nitrogen fertilizer on barley were evaluated in a completely randomized design with three replications, under greenhouse conditions. Quantity salinity tolerance and susceptibility indices such as Mean Productivity (MP), Tolerance Index (TOL), Geometric Mean Productivity (GMP), Stress Susceptibility Index (SSI), Reduction Yield Ratio (Yr) and Stress Tolerance Index (STI) on the basis of plant yield with stress (Ys) and without stress (Yp) conditions were determined. Results showed that STI had a positive and highest significant correlation with grain and straw yields, compared to other indexes. Study of Standard Beta contents in grain and straw with STI index showed that the impact of Cl had a greater effect on reduction of salinity tolerance than SO4. Also Cl/SO4 ratios of 1:3 and 1:2 for grain and 1:2 and 1:1 for plant straw brought about highest tolerance to salinity, compared to non stress conditions. The scatter plot also confirmed such findings.
M. Boyerahmadi, F. Raiesi , J. Mohammadi,
Volume 14, Issue 51 (4-2010)
Abstract
Similar to plants, soil salinity may reduce microbial growth and activities in different ways. The aim of this study was to determine the effects of different levels of salinity on some microbial indices in the presence and absence of plant's living roots. In this study, five levels of salinity using NaCl, CaCl2, MgCl2 and KCl and three soil media (soil with no plant, soil cultivated with wheat and clover) replicated three times consisted our factorial experiment arranged in a completely randomized design. Results show that salinity caused a significant reduction in accumulated microbial respiration, microbial biomass carbon, substrate-induced respiration, and carbon availability index in uncultivated soil and in the soils planted with clover and wheat. Results also show that salinity caused a significant increase in metabolic quotient (qCO2) in uncultivated soil, and soils planted with clover and wheat. Microbial activity of cultivated soils at high salinity levels was almost similar to that of the uncultivated soils. We observed a small difference in soil microbial activity among the three media at high salinity levels, indicating the role of indirect effects of salinity might be less important with increasing salinity levels. We also found out that at low salinity levels, the available carbon was not a limiting factor for soil microflora, while at high salinity levels the activity of soil microbes might be carbon-limited. The lower values of qCO2 in cultivated soils compared with the uncultivated soil support the positive influence of root and its exudates on soil microbial activity in saline soils. The existence of plants in saline environments may help in alleviating the detrimental influence of low to medium salinity on most soil microbial activities, likely via the added root exudates and root turnover.
Atlassi Pak, Nabipour , Meskarbashee ,
Volume 14, Issue 51 (4-2010)
Abstract
Gray mold, caused by Botrytis cinerea, is a serious disease of cut rose flowers (Rosa hybrida L.) in Iran. In order to elucidate the effects of different potassium and calcium levels in nutrient solution on susceptibility of cut rose flowers to gray mold, this experiment was carried out as factorial design in a randomized complete block with four replications at Safi Abad Agricultural Research center in 2008 for one year. In this experiment, rose plants were grown and subjected to three levels of potassium (1.0, 5.0 and 10.0 mM) in combination with two levels of calcium (1.6 and 4.8 mM) under hydroponic condition. Rose flowers from two consecutive harvesting periods were sprayed with the conidial suspension (104 spore/ml) of B. cinerea isolate. At the end of experiment the disease severity was recorded and analyzed. The results indicated that application of 10.0 mM K in the nutrient solution led to increasing rose disease severity to gray mold (30.4 % day-1) compared to 1.0 mM (24.8 % day-1) and 5.0 mM (26.2 % day-1) of K levels (P< 0.01). The increased susceptibility was associated with a decreased concentration of Ca in the rose petals. Correlation analysis revealed that susceptibility of rose flowers to gray mold significantly increased with K to sum cations ratio in the nutrient solution (r = 0.94*). The increase of Ca supply from 1.6 to 4.8 mM resulted in decline of disease severity from 29.6 to 24.6 % day-1 (P< 0.01). Therefore, balanced application of potassium and calcium (5.0 and 4.8 mM, respectively) is recommendable for preventing antagonistic effects between them and reducing of rose gray mold intensity under hydroponic conditions.
M Gorgi, M Zahedi, A. H Khoshgoftarmanesh2,
Volume 14, Issue 53 (10-2010)
Abstract
An experiment was conducted in order to evaluate the effects of increased concentration of potassium and calcium in hydroponic nutrient solution on the response of safflower to salinity. The experiment was carried out in a glasshouse using a completely randomized design. Four saline treatments (Johnson solution containing 100 mM of NaCl, Johnson solution containing 100 mM of NaCl + 10 mM potassium, Johnson solution containing 100 mM of NaCl + 5 mM calcium, Johnson solution containing 100 mM of NaCl + 10 mM potassium + 5 mM calcium) and Johnson solution without any addition of salt as control. Leaf area per plant, shoot and root dry matter was decreased in saline treatments. The concentration of potassium and calcium in the plants were decreased but those of sodium were increased at salinity. The extent of shoot and root dry mater reduction with salinity was less in saline treatment with additional calcium alone. The addition of potassium into the nutrient solution could not mitigate the negative effects of salt stress on the plants. Increasing the concentration of both potassium and calcium in saline nutrient solution resulted in a greater reduction of shoot dry matter. The results showed that the negative effects of salinity may be alleviated by increasing the concentration of calcium in nutrient solution.
A. Haghverdi, B. Ghahraman, M. Kafi, K. Davari ,
Volume 15, Issue 58 (3-2012)
Abstract
The objective of current study was to perform screening experiment, (phase zero of response surface methodology) the analysis of salinity and water tensions for spring wheat in Mashhad region and derive water production functions. The experiment was performed in the Research Field of Agricultural Faculty of Ferdowsi University of Mashhad in 2009-2010. Two water sources were selected: saline water (10 dS/m) and water without salinity limitation (0.5 dS/m). A single replicate factorial experiment with four variables and water requirements in different growth stages, was done with each variable having two levels, 20% and 100% of water requirements. The central points of experiment area with two replications were added for estimating the curvature in the fitted response surface. The results showed the water requirements in heading and flowering were the most important variables. The fitted water production functions estimated the yield of saline and non saline plots with correlation coefficients equalsing 0.95 and 0.99. In general, the obtained results proved the efficiency of the screening experiment in identifying the relative importance of variables and excluding the ineffective variables
M. Navabian, M. Aghajani,
Volume 16, Issue 60 (7-2012)
Abstract
In Guilan province, Sefidrud River, as the main source of irrigating rice in Guilan province, has been subjected to increasing salinity and a decreasing discharge because of decreasing in the volume of sefidrud dam, diverting water upstream and entering different sewages into the river. This research tries to determine optimum irrigation depth and intermittent periods in proportion to salinity resistance at different growth stages using optimization- simulation model. After calibration, Agro-hydrological SWAP model was used to simulate different growth stages of rice. Optimization results were obtained for managing fresh and saline intermittent water, 8-day intermittent period, for salinity of 0.747 dS/m in sensitive maturity stage and salinity of 3.36 dS/m in resistant vegetative, tiller and harvest growth stages. It is suggested that the depth of irrigation water be 1, 3, 3 and 5 cm for vegetative, tiller, maturity and harvest stages, respectively. Comparing managements of irrigation and saline based on the resistance of different growth stages to salinity and exploitation of irrigating water with a constant salinity during growth periods of the plant showed that irrigation management based on resistance of different growth periods of the plant to salinity causes rice yield to be improved by 23percent.
S. Eskandari , V. Mozafari,
Volume 16, Issue 60 (7-2012)
Abstract
A greenhouse experiment was conducted to study the effects of soil copper (Cu) and salinity on growth and chemical composition of two pistachio cultivars. A factorial experiment was carried out as a completely randomized design with three replications. Treatments consisted of four Cu levels (0, 2.5, 5, and 7.5 mg Kg-1soil as CuSO4.2H2O), five salinity levels (0, 800, 1600, 2400, and 3200 mg NaCl Kg-1 soil) and two pistachio cultivars (Badami-e-Zarand and Ghazvini). Results showed that salinity significantly decreased growth parameters. Application of 3200 mg NaCl Kg-1 soil decreased shoot and root dry weights, leaf area and stem height by 67, 72, 45 and 76 % respectively. Application of 7.5 mg Cu Kg-1 soil increased shoot dry weight and leaf area by 24 and 26% respectively. Morever, there was no significant difference between growth parameters of two pistachio cultivars, except for leaf area index. Salinity stress significantly decreased shoot and root P, k and Cu total uptake, and increased that of Na and Cl. Application of 5 mg Cu Kg-1 soil significantly increased shoot Cu uptake. Since total uptake of all elements for Badami cultivar was significantly higher than the Ghazvini, it could be concluded that the latter cultivar is probably more resistant to the saline conditions.
A. R. Vaezi, A. Hoseinshahi, P. Abdinejad,
Volume 16, Issue 62 (3-2013)
Abstract
Flood spreading is one of the suitable methods to control the floods and conservation of soil and water in arid and semi-arid regions. Since soil properties may be influenced by the flood spreading, this study was carried out to investigate the effect of the flood spreading on physicochemical soil properties in Garacharyan plain located in North West of Zanjan in 2009. Three flooded areas and one control area were selected for soil sampling. Two hundred sixteen soil samples and twenty seven soil samples were taken from three flooded areas and control area, respectively. Soil infiltrability was also measured at three points both in the flooded areas and in control area. Results of the physical soil properties indicated that the soil infiltrability and available water content were significantly (p< 0.001) affected by the flood spreading in the study plains. With a decrease in sand percentage and an increase in clay in the flooded areas, soil infiltrability strongly declined. The available water content negatively correlated (p< 0.001) with clay in the areas. Soil chemical properties, including salinity, potassium, and bicarbonate, contrary to pH and total neutralizing carbonates and nitrogen, significantly (p< 0.001) increased in the flooded areas as compared with control area. Increasing of the salinity in the flood plains is associated with potassium in the flood plains (p< 0.001). There was no significant difference in organic matter and carbonate contents between the flooded areas and control area. The study revealed that controlling suspended load and solvent solids in the floods is necessary to prevent the degradation of the soil physicochemical properties (porosity, infiltration, plant water supply, and salinity and bicarbonate) and as a result improve the effectiveness of the flood spreading method in the flooded areas.
B. Khalili Moghadam, Z. Ghorbani, E. Shahbazi,
Volume 18, Issue 69 (12-2014)
Abstract
Salt with various kinds and contents is one of the most important factors affecting soil splash erosion rate. The aim of the present study was to evaluate various salinity and alkalinity levels on splash erosion rate and its components (upslope, down slope and total splash) in different slopes. A factorial experiment with three factors was conducted in a completely randomized design with three replications by a Multiple Splash Set (MSS). The treatments included splash erosion rate at 4 levels of salinity and alkalinity (EC: 2 dSm-1, SAR: 2، EC: 15, SAR: 24 ،EC: 56, SAR: 42، EC: 113, SAR: 47), two levels of rainfall intensity (2.5 and 3.5 mm.min-1) and 5% and 15% slope levels. The results showed that the organic carbon and mean weight diameter (MWD) decreased at higher levels of salinity and alkalinity. The effect of saline and sodic, slope and rainfall intensity levels on the splash erosion rate and its components was significant. Also, slope×saline and sodic, rainfall intensity×saline and sodic, slope×saline and sodic×rainfall intensity interaction treatment caused a significant increase in splash erosion rate and its components. It seems that splash erosion is increased in saline and sodic soils due to the reduction in OC and MWD
