JWSS - Journal of Water and Soil Science

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Understanding the nitrogen remobilization by plant, in order to obtain cultivars with higher quality, has specific importance in plant physiology. In this experiment, a bread and a durum wheat cultivar, were treated with different rates and times of nitrogen application, by using split factorial on the basis of randomized complete block design with three replications at Shiraz region during 2001-2002. Main plots consisted of two levels of cultivars ( Falat and Yavaros) and sub plots included nitrogen (40, 80 and 160 (kg ha^-1) and times of nitrogen application (T1= all N fertilizer at planting , T2= 1/2 at planting + 1/2 during stem elongation and T3= 1/3 at planting + 1/3 during stem elongation + 1/3 at heading stage). The results showed that there was a significant difference between cultivars in flag leaf nitrogen content at maturity stage, N remobilization and its efficiency from flag leaf to grains and also grain protein percentage. Durum wheat was more efficient in nitrogen remobilization and therefore, had a higher grain protein percentage. Increase in rates and times of nitrogen application had significant effect on most of the measured traits. There were significant interactions between cultivars, rates and times of N application, indicating that durum wheat was more efficient in N remobilization from flag leaf to the grain. It appeared that N remobilization efficiency was the important factor affecting the grain protein percentage. Also increases in yield are associated with corresponding decreases in wheat protein.

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To determine the effects of different intensities of leaf removal at different reproduction stages of sunflower on seed yield and oil percentage, and the most sensitive stages to defoliation, an experiment was carried out by split-spilt plot design in randomized complete block with 3 replications at research farm, College of Agric. Urmia University, in 2004. The main factor, sub factor and sub-sub factor in our experiment were: 1. two cultivars, Uroflor and Alstar, 2. defoliation at four reproduction stages, star shape of inflorescence (R₂), pollination stage (R₅), seed setting initiation (R₆) and final period of seed setting (R₇), and 3. four defoliation intensities ( 0% as an undefoliated control, 25%, 50% and 75% ). Seeding was accomplished on May 23. Average triple factor interactions verified that different defoliations at R₂ stage have significantly reduced seed yield and oil percentage of both Uroflor and Alstar cultivars. Out of this reduction, 75 percent defoliation at R₂ was the most, while at R₅ and R₆ stages 50 and 75 defoliation caused significant reduction on seed yield in comparison with control. At R₇ stage different defoliations had no significant effect on seed yield of Uroflor cultivar, while, on Alstar cultivar, 75 percent defoliation at R₇ stage caused significant difference in relation to control. Also average triple interaction among factors showed that none of defoliation percentages had significant effect on oil percentage. In view of the fact that, seed development and filling occurred after defoliation at R₂ and R₅ , the most variation resulted from defoliation of valued traits like number of filled seed per head and weight of 1000 seeds, observed at R₂ and R₅ stages and consequently reduced seed and oil yields. On the bases of this experiment it could be concluded that sunflower cultivation with losses of 50 and 75 percent will be economically unprofitable and it will be more desirable to replace it with any other suitable crop in the region.

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Mayonnaise sauce is a nutritious food product with high caloric content, which is usually incorporated into other products as an ingredient. The product should be produced under hygienic conditions to avoid its physical and chemical deterioration along with microbial spoilage, which mostly happens due to the lack of thermal treatment. Mayonnaise is often stored for long periods at room temperature in large plastic containers before consumption. To carry out the investigation, samples of the sauce in large plastic containers and glass jars were obtained directly from a commercial producer. After preliminary quality examinations, they were allocated into 3 lots and stored at 5, 25 or 40^oC for up to 6 months. They were then subjected to physical, chemical, microbiological and organoleptic tests at monthly intervals. The results showed no significant microbial growth even when kept at higher temperatures. Significant chemical changes (autoxidation), however, occurred in both containers at temperatures close to 40^oC. Organoleptic examinations revealed significant changes, especially in color and emulsion stability, which were more evidenced for those stored at higher temperature. It was concluded that the storage of mayonnaise sauce in large plastic containers at higher temperatures should be avoided mostly due to deterioration through physical, chemical and organoleptic changes of the sauce.

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This study was conducted to investigate the effect of formic and sulphuric acids on chemical composition, dry matter (DM) and crude protein (CP) degradability of alfalfa silage and its effect on early lactating Holstein cow as three trials. In the first trial, chopped alfalfa (22 and 33% DM) was ensiled with three levels of formic acid (0.0, 15 and 20 ml/kg DM) and two levels of sulphuric acid (0 and 4 ml/kg DM). In the second trial, DM and CP degradability coefficients of silages (Treatment 1: without acid Treatment 2: 15 ml formic acid + 4 ml sulphuric acid per kg DM) and alfalfa hay (Treatment 3) were determined using nylon bag technique in two cannulated steers. In the third trial, silages (treatments 1 and 2) were replaced with 50% of alfalfa hay in the early lactation Holstein cow diet (11 cows, 19 ± 8 days in milk). Diets were fed for 49 days. Dry matter intake, milk production and milk composition were evaluated. Blood metabolites were determined in weeks 4 and 6. Effect of wilting on pH was significant (p<0.05). Quickly degradable fraction (a) of DM was similar in both silages (0.35) but was higher (0.5) for hay rather than the silages. Slowly degradable fraction (b) of DM of the acid - treated silage was higher compared with the hay (0.39 and 0.32, respectively). Fraction (a) of CP in acid treated silage was less than the control silage and hay (0.46, 0.57 and 0.57, respectively). Fraction (b) of CP in acid - treated silage was less compared with the control silage and hay (0.41, 0.28 and 0.35, respectively). There were no significant differences between the treatments on the cow’s performance. However, time effect on milk fat and solid non-fat was significant (p<0.01). Blood glucose concentration before feeding with treatment 2 was significantly higher (p<0.01) than cows feeding with treatment 1.

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The increased potential for soil erosion and compaction due to continuous row crop production and intensive tillage is causing some concern and has led to the consideration of reduced tillage techniques as part of the solution. The objective of this study was to investigate the short-term (one-year) influences of different management practices on the physical properties of a sandy loam soil under corn crop. Treatments were the combinations of three tillage systems (no-till, NT chisel plow, CP and moldboard plow, MP) and three composted cattle manure rates [0, 30 and 60 ton (dry weight) ha^-1]. The experiment was carried out in a split-plot design. Three replicates of the treatments were applied in a randomized block design. Saturated hydraulic conductivity (K_s), total porosity (TP), macro-porosity (Macro-P), micro-porosity (Micro-P) of soil and mean weight diameter (MWD) of aggregates, were measured to a depth of 22.5 cm when 100 percent of the tassels appeared. Tillage and manure combination had significant effects on Log[ K_s], TP, Macro-P and Micro-P. The MP system increased pore space and continuity due to complete inversion and loosening, and as a result K_s, TP, Macro-P and Micro-P were higher than NT system. Higher Macro-P observed for CP might have caused higher K_s versus MP. Reduced tillage systems increased MWD and the increment of manure caused an increase in MWD over all tillage treatments. The results indicate short-term positive effects of manure application on soil pore size characteristics and aggregate stability under moldboard and chisel plowings in the region.

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The effect of overgrazing on vegetation changes in central Zagros has been studied by a few scientists, but there is no detailed information on the impact of such practices on soil properties. The objective of this study was to assess the effect of climate and grazing management on selected soil biochemical properties. Fourteen experimental range sites protected against grazing as well as their adjacent overgrazed sites in Chadegan, Pishkuh and Poshtkuh were selected. In each site, samples were collected from the depths 0-5 and 5-15 cm. Soil organic C (OC), microbial biomass C (MBC), total nitrogen (TN), organic C to total N ratio (C/N), microbial biomass C to organic C ratio (C_mic/C_oc) and metabolic quotient (qCO2) were measured and/or calculated. The results showed that the lowest SOC, MBC, TN and Cmic/Coc occur in Chadegan due to low fresh materials input. The above parameters in Pishkuh and Poshtkuh regions are 2.5 to 3 times greater than those in Chadegan area. Grazing intensity in Pishkuh is less than that in Poshtkuh region and there is no significant difference between grazed and protected sites in Pishkuh. But, there is a significant difference between grazed and protected plots in Poshtkuh due to a higher grazing intensity. Higher C_mic/C_oc and lower qCO2 suggest that the quality of organic matter is better in Poshtkuh and Pishkuh. In conclusion, highly degraded rangelands in Pishkuh and Poshtkuh seem to be able to recover very quickly with proper management, while Chadegan region needs a much longer period of time to restore.

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This study was performed in two barley fields, in Experimental Station, Agricultural College of Ferdowsi University of Mashhad in 2003. Sampling was done by systematic method in which samples were taken from the corners of 7m*7m grids using 0.5m 0.5m size quadrates in three stages (pre herbicide, post herbicide and pre harvesting stages). The results indicted that the density of annual weed seedlings in sugar beet- barley rotation was more than fallow- barley rotation, and the density of perennial weed seedlings in fallow-barley rotation was more than sugar beet- barley rotation. Map of species distribution and density confirmed patchiness distribution of the weeds. The shape and size of patches differed based on the field and weed species, but spatial distribution did not change considerably before and after the application of herbicide. Percentage of free weeds area was 11.5% and 1.5% in fallow-barley rotation and 0.6% and 0% in sugar beet- barley rotation in the first and second sampling stages, respectively. These results indicate beside emphasis on weed infestation. The result also indicates inefficacy of sugarbeet-barley rotation compared to follow-barley rotation. Apparently, the evaluation of management and paying special attention to weed dispersal within the field assist in the implementation of appropriate management strategy, which includes high efficacy, and profit for farmers as well as least damage to crops.

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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.

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The purpose of this study was to assess characteristics of and reasons for farmers’ disagreement on implementation of land consolidation projects. Part of needed information was collected through questionnaire and interviewing 75 farmers in 6 unsuccessful villages in Kermanshah and Lenjanat region and also visiting some performed and ongoing projects. Other part of information was obtained by questionnaire and interviewing 44 experts involved with performing the project in Jahad Agricultural offices. Fragmentation of properties were measured by Januszewski fragmentation coefficient. Correlation coefficient and comparison of mean were used to analyzed the information. The results showed that disagreement of farmers is the most important obstacle for progress on land consolidatin projects, which accounted for farmers. In Lanjanat, these farmers have a better land structures in respect to size and fragmentation of parcels. In both rejoin reasons for farmer’s disagreement are divided in three groups: logical-justified reasons, logical-unjustified and illogical. Mediation, preference and legislative force are the three interactive methods to satisfy these farmers. To decrease disagreements and promote land consolidation in the two regions, following suggestions are offered: education and extension, correcting the technical and adminestrative methods of land consolidation and legal and judicial supports to implement the projects.

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  During the past years, safflower genotypes have been selected from local variety of Isfahan, named Kouseh. The response of these genotypes to planting date might be different. To determine this, performances of several genotypes selected from Kouseh plus Arak 2811 ) as check ( were studied at the Agricultural Research Station, Isfahan University of Technology in 2002-2004. The experiment was conducted using a split-plot arrangement within a randomized complete block design with three replications. Planting dates were considered as the main plots and subplots consisted of 22 genotypes of safflower. Number of days from planting to emergence was highest (18.0 days) in early spring planting and lowest (10.3 days) in late spring planting. Days from planting to head visible, flowering and physiological maturity were decreased with delay in planting from autumn to late spring. Days from planting to emergence, head visible and physiological maturity were not influenced by genotype. Genotypes C116 and DP29 had the highest (145.0) and genotype ISF28 the lowest (140.2) days from planting to flowering. Plant height, number of first and second degree branches, number of heads per first and second degree branches, number of seeds per head, 1000-seed weight and seed weight per plant reduced significantly with delay in planting from autumn to late spring. Genotypes C128 and DP7 had the highest (120.0 and 120.5 cm, respectively) and genotype DP9 the lowest (104.2 cm) plant height. Genotypes DP6 and DP9 had the highest (12.8) and the lowest (6.7) first degree branches per plant, respectively. Arak-2811 had the highest (16.9) and genotypes DP9 and DP5 the lowest (7.2 and 7.1, respectively) second degree branches per plant. Number of heads per first degree branches was not significantly affected by genotype. Arak-2811 and genotype C114 had the highest (12.8 and 12.2, respectively) and genotype DP9 the lowest (5.1) number of heads per second degree branches. Genotype DP7 had the highest (45.9) and genotype C111 had the lowest (28.0) number of seeds per head. Genotypes DP3 and C128 had the highest (34.2 g) and lowest (22.0 g) 1000-seed weight, respectively. Genotype DP25 had the highest (20.5 g) and genotypes DP29 and DP9 the lowest (9.9 and 10.0 g) seed weight per plant. Harvest index was not affected by planting date and genotype. The result of this study showed that safflower may yield more in fall planting under conditions similar to this experiment. Genotype DP25 might be recommended for this planting date, genotypes ISF66 and DP25 for early spring planting and genotypes DP7 and ISF14 for summer planting.

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  Photosynthesis and wheat grain yield responses to supplemental irrigation with different amount of applied water under dryland conditions were investigated. Therefore, a two-year field experiment was conducted research farm of College of Agriculture, Shiraz University during 2004-2005. Five levels of irrigation including dryland conditions, irrigation at stem elongation, booting, flowering and grain filling were main plots and two wheat cultivars: Agosta and Fin-15 were subplots, and three rates of nitrogen including zero, 40 and 80 kgha^-1 were sub sub-plots. The results showed that in both years, photosynthetic rate, stomatal conductance, substomatal CO₂ concentration and transpiration rate, were significantly higher under irrigation at stem elongation stage compared to other supplemental irrigation treatments. In all of the four supplemental irrigation treatments, photosynthetic rate, stomatal conductance, substomatal CO₂ concentration and transpiration rate decreased with decreasing the amount of applied water to each plot. In both years, the highest grain yield was obtained from supplemental irrigation at stem elongation stage, and the lowest yield was harvested at dryland conditions. The highest photosynthetic parameters, yield and yield components were obtained from interaction of supplemental irrigation at stem elongation stage × Fin-15 and 80 kg N ha^-1 in both years. The supplemental irrigation in 2004 and 2005 increased the grain yield 200 and 221 percent, respectively, compared to dryland conditions. Thus, supplemental irrigation at sensitive stem elongation stage could affect significantly wheat grain yield of rainfed wheat cultivars and provision of adequate water for a supplemental irrigation at the appropriate growth stage could double the grain yield of rainfed wheat.

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  Blast, caused by Magnaprthe grisea, is often an important fungal disease in the production of rice in temperate and tropical areas including Iran. To determine reaction of rice cultivars against blast disease, 40 rice genotypes from Iran and other sources from Asia were selected. Four blast isolates from different races were used to test all rice genotypes in different greenhouse tests. In blast nursery, experiments were conducted in a Randomized Complete Block Design (RCBD) with three replications. In different experiments inoculated plant materials were evaluated for Infected Neck Number(INN), Neck Lesion Size(NLS), Infection Type(IT), Diseased Leaf Area(DLA), Area Under the Disease Progress Curve(AUDPC), Lesion Number(LN), and Sporulating Region Diameter(SRD). Most of the Iranian traditional cultivars together with CO-39 and C104-PKT showed susceptible reaction for AUDPC, IT, INN and NLS. Performance of improved cultivars from Iran, IRRI and NILs (except C104-PKT) was resistant. Some cultivars including Fujiminori, Onda , Hassan saraii were moderatly susceptible to leaf blast in blast nursery. All components of resistance in both growing stages in greenhouse and nursery tests were significantly correlated. In some cases such as cultivar Haraz different reaction was observed in seedling and flowering stages, indicating that genetics of resistance in two stages could be different.

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  The purpose of this research was to study factors on farmer’s request to land consolidation projects and also consolidation’ adventages in utilization units. The data of this study was collected through completing questionnaires and interviewing 34 experts connected with administrating of land consolidation projects in agricultural offices and service centers in Kermanshah township and Lenjanat region in Isfahan. Data was also collected through visiting some performed and performing projects. The results showed that in Kermanshah land consolidation improves the technology, farm management and land more than other production factors. In Lenjanat it improves technology and farm management in comparison with other factors. In both regions the aplicant villages of the projects have a larger ownership and more fragmentaed parcels than other villages. Moreover they have younger exploiters, more educated and less in number. It is also notworthy that these regions obtain more extention education, are nearer to agricultural offices, and have closer relation with extention agents.

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  The purpose of this study was to investigate and analyze the factors affecting farmers’ attitudinal dimensions toward participation in Water Users’ Association (WUA) by comparing two groups of farmers in irrigation networks with WUA and without it. The methodological approach was a descriptive-correlational and causal-comparative study of the survey type. The target population in the study consisted of 2551 farmers of irrigation networks in Khorasan-e-Razavi Province, Iran. Using stratified random sampling technique, 335 participants were chosen. Data were collected through a questionnaire, and analyzed using SPSS, V.13. Content and face validity of the instrument were obtained by the faculty members of Agricultural Extension and Education, Agronomy and Irrigation Departments at Tarbiat Modarres University and also specialists board of Agricultural Jihad Organization and Regional Water Joint-stock Company in Khorasan-e-Razavi Province. The reliability analysis was conducted and cronbach’s alpha values for the various sections of instrument were estimated between 0.73 and 0.86. The descriptive findings of the study showed that the majority of farmers’ overall attitude with respect to participation in WUA was at a good level. The results obtained from Pearson correlation analysis indicated that there are significant and positive relationships between such variables as education level, size of irrigated cultivated landholding, annual income, extension contacts, social capital components, water users’ perceptions regarding irrigation networks status and farmers’ participation status concerning irrigation networks management with the farmers’ overall attitude toward participation in WUA. The result of stepwise multivariate regression analysis indicated that 61.1% (R² = 0.611) of the variance in farmers’ attitudes with respect to participation in WUA could be explained by farmers’ behaviour regarding optimum farm water management, social participation, social confidence, water users’ perceptions regarding irrigation networks status, farmers’ participation status concerning irrigation networks management. Also, significant differences were found between the two respondent groups in irrigation networks with WUA and without it in relation to farmers’ attitudinal dimensions.

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  Continuous measurement of river discharge is a hard and expensive task in hydrology. To overcome this problem, the stage readings at hydrometric gauges are permanently taken and the discharge of any time at which the actual discharge is unavailable will be estimated through a relationship between discharge and stage. To study the stage-discharge relations and the capability of long-term data in establishing a permanent stage-discharge relationship, and also to determine the best time to measure the discharge of rivers, a study was conducted at the hydrometric station of the Zayandehrud regulatory dam using data from 1990 to 2003. The data were analyzed using simple regression analysis, the percentage of relative error and factor analysis. The results indicated that the best model to show the stage-discharge relation at the studied station is a power function model. Moreover, the model used for every year can only be used for that year. The results also showed that the most suitable times for the measurement of discharge are July, December and March.

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  Organic fertilization has been practiced in Iran due to the shortage of soil organic matter. In recent years, attention has been payed to the organic fertilizers because their commercial production has recently started and demands for their application have increased. The objectives of this study were to investigate the effects of organic fertilizer type, rates and times of application on the N mineralization potential (NMP) in a calcareous soil (fine loamy, mixed, thermic, Typic Haplargid) in Isfahan region. The soil samples were collected from a previousely established field experiment. The experiment design was split plot with three replications. Each main plot was split into subplots receiving 1, 2 and 3 annual consecutive applications of cow manure and sewage sludge at the rates of 0, 25 and 100 Mg ha^-1. The soil samples were taken from 0-15 cm depth, 6 months after the third application of the organic fertilizers. Nitrogen mineralization potential was measured by a long-term leaching-incubation procedure. Results indicated that NMP was similarly affected by cow manure and sewage sludge. Nitrogen mineralization potential in the treatments which received 100 Mg ha^-1 organic fertilizers, was 4 and 1.7 times greater than that of control and 25 Mg ha^-1 treatments, respectively. A significant increase was also observed in NMP in the treatments which received different times of application. The NMP in the three-year applied treatments was 5, 2.5 and 2.1 times greater than that of control, two- and one-year applied soils. Significant correlations were observed between NMP and corn yield (r=0.531**) and corn N uptake (r=0.568***). The product of NMP and N mineralization rate constant was also significantly correlated with corn yield (r=0.710***) and corn N uptake (r=0.734***). Different patterns were observed between the responses of total N and NMP in the treated soils.

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  Adopting proper agricultural management and conserving soil organic matter are important components of sustainable agriculture. Soil organic matter content is a key attribute in soil quality. Labile organic matter pools can be considered as suitable indicators of soil quality that are very sensitive to changes in soil management practices. This research was carried out to investigate some organic carbon labile pools as an indicator evaluating the effects of different managements on some quality parameters of two calcareous soils. The study was conducted in 2 locations: 1- plots that receiving 0 (C1), 25 (C2), 50 (C3) and 100 (C4) Mg/ha of manure for five years successively with a cropping rotation of wheat –corn every year and plots under three cropping rotations (C5, C6 and C7) at Lavark experimental farm and 2- inquiry research station of Fozveh at different plots with three different cropping rotations (C8, C9 and C10) with a given cropping history recorded for the last 5 years. Soil samples were taken from the center of each plot and the depths of 0-5 cm and 5-15 cm. Their organic carbon, hot water soluble carbohydrate, particulate organic matter (POM), organic carbon and hot water soluble carbohydrate of POM, mean weight diameter of water stable aggregates were determined. Different managements consisting of different levels of manure and types of cropping rotation had significant effects on the soil characteristics measured. The greateast amount of carbohydrate and aggregate stability was obtained in the plots of 100 Mg/ha of manure in Lavak and in alfalfa plots in Fozveh station. Also, the results showed that aggregate stability has a better correlation with hot water soluble carbohydrate in comparison with other soil organic pools. Therefore, the carbohydrate extracted by hot water may be used as an index to assess the impacts of different agricultural management systems on soil quality.

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  Tillage is one of the important managing factors that can destroy or improve soil structure. Soil structure is affected by the machines and shape of the wheels. Field experiments were conducted at Hamadan Agricultural Research Station on a coarse loamy mixed mesic Calcixerolic Xerocrepts soil to measure and evaluate the effects of tillage and wheel-induced compaction on selected soil physical properties. Treatments included tillage methods (Moldboard Plow and Chisel Plow, (MP, CP)) performed using three customary tractors in Iran [John Deer (J), Romany (R) and Massey Ferguson ( MF) ]. Traffic zone and non traffic zone were other treatments. A split-plot design with three replications was used in a completely randomized arrangement of treatments. Soil samples were taken at the end of wheat growth season in traffic and non- traffic zone and from four layers and compared for bulk density (BD), cone index (CI), and mean weight diameter (MWD). The influence of both tillage methods on BD in most soil depths was not significant, meanwhile, BD was higher in the deeper layers. Wheel traffic did not affect BD significantly, but its effect decreased by increasing the depth. Commonly, conservation tillage increased structural stability as evaluated by MWD. Cone index illustrated the same trend as for BD, with some variation because of it higher sensitivity, so it was significantly was increased in CP rather than in MP for the traffic zone. Such a difference was not observed in non-traffic zone. The CI was also significantly increased in traffic zone compared with non-traffic zone. J significantly increased CI in two first layer in comparing with MF, but there was not significant difference between J and R. The MWD was increased by chisel plow in non-traffic zone and this increment was significant in fourth soil layer (22.5- 30 cm). Wheel traffic caused the increase of MWD in the second layer and significant difference was not observed in other layers. Overall, R caused less destruction in soil structure and tillage methods changed some of soil physical properties.

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  Application of slag and converter sludge, major by-products of Esfahan Zob Ahan factory, to enrich two organic amendments for corn nutrition, was investigated. Farm manure and its vermicompost mixed with different rates of slag and sludge were incubated in 3 Kg pots at field capacity moisture and home temperature for three months. The applied rates of slag and sludge were 0, 5 and 10 percent (w/w) of pure iron from these compounds to the organic amendments. Iron sulfate with the above ratios was also examined for comparison. Sub-samples of the incubated materials were taken after 0, 10, 25, 45, 65 and 90 days of incubation and examined for DTPA extractable Fe, Mn, Zn and Cu. After the incubation, the enriched amendments were applied to a soil sample to grow corn. Three Kg soil samples, taken from Chah Anari experimental farm, Esfahan University of Technology, were mixed with 17 gr of the amendments (50 ton/ha) placed in 3 Kg pots. In each pot two corn seeds (single cross 704) were planted and after 70 days crop yield and concentration of Fe, Mn, Zn, Cu in the plant tissues were determined. Results showed that the use of iron sulfate strongly increased DTPA extractable Fe and Mn of the amendments. In enrichment by converter sludge, the best result was obtained in the mixture of 10 percent pure iron with the vermicompost on 60 days of incubation. Treatment of 5 percent pure iron from slag mixed with the manure increased DTPA extractable Fe and Mn with the time, but the 10 percent treatment was not much effective in this regard. The highest rates of iron uptake by the plants occurred in the iron sulfate and 10 percent converter sludge treatments, respectively however, the highest rate of the plant Mn uptake was observed in 5 percent iron from converter sludge mixed with vermicompost. In general, 10 percent pure iron from converter sludge was the most effective enrichment treatment, increasing the plant uptake of Fe, Mn, Zn and Cu micronutrients.

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  Applying of intensive cultivation especially in marginal and sensitive regions, after conversion of rangelands to cropland farms, commonly causes reduction in soil quality, and thus an increase in soil degradation, erosion and runoff. This study was conducted to evaluate the land use change effects on some soil physical and chemical properties such as mean weight diameter (MWD), soil organic matter (SOM), bulk density (BD) and saturated electrical conductivity (ECe). For the experiment, soil samples were collected from 8 regions (rangeland and cultivated range) from west and southwest of Isfahan. Samples were taken from two soil layers 0-15 and 15-30 cm. Results showed that after conversion of range to cultivated lands, in some regions, SOM content was increased about 39% but in some regions decreased about 26%. This is due to the initial conditions of the regions. The ECe also increased by 41% due to this conversion. However, no changes were observed to the MWD, BD and pH in different treatments. Although there were little change to the physical and chemical properties of soil as a result of this conversion, those properties which were changed, could have a degradation effect and lower the soil quality.