JWSS - Journal of Water and Soil Science

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Turfgrass is important in urban landscape and by considering that organic matter has a important roll in improving physical and chemical soil characteristics using an organic matter instead of manure and MSW seems necessary .in this research the possibility of using new method of culture such as hydromulching (i.e. mixing seed, organic matter, water, and fertilizer and then distributing it) spent mushroom compost (SMC) has done .for these reason we use two level of SMC 6- month old and one –year old .in two time ,spring and autumn .the experiment design as a factorial Randomized Complete Block Design with 3 replications .Germination ,establishment ,uniformity ,density ,color was measured .results showed that SMC is better than manure especially 6-month old SMC as it is than one-year old SMC .in the spring establishment and germination is better . So using hydromulching by 6-month compost in spring is recommended.

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Phytoremediation is a new, in-situ and emerging remediation technology for contaminated soils. This technology, compared to other methods, is a sustainable, natural, relatively cheap and applicable to large scale area. Modeling phytoremediation provides quantitative insight for the governing process as well as for managers to assess the remediated sites. The objective of this study was to introduce a macroscopic phytoremediation model for Ni and Cd- polluted soils. The proposed model assumes that relative transpiration reduction function can resemble total soilNi and Cd concentrations. Combining the related functions of soil and plant responses to soil Ni and Cd concentrations, the phytoremediation rate of Ni and Cd was predicted. In order to test the proposed model, large quantities of soil were thoroughly polluted with Ni and Cd. Upland Cress (Lepidum sativum) and Ornamental Kale (Brassica olerace var. Viridis) seeds were then germinated in the contaminated soils. The experimental pots were irrigated with fresh water to reach field capacity. Upland Cress and Ornamental Kale were harvested three and four times, respectively. At each harvest, relative transpiration, Ni and Cd contents of soil samples and plants were measured. Comparison of the maximum error, root mean square error, coefficient of determination, modeling efficiency and coefficient of residual mass indicated that the non-threshold non-linear model provide high efficiency to predict relative transpiration for Upland Cress and Ornamental Kale, respectively. The results also indicated that the proposed macroscopic model can well predict the phytoemediation rate of the Ni and Cd by Upland Cress (R2>0.83) and Ni by Ornamental Kale (R2=0.78).

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Nowadays in the world, soilless culture as a kind of technique is known to give vegetable crops higher yield and quality. This experiment was conducted at research greenhouse of Agriculture and Natural Research Center of Golestan province in spring 2005. The purpose of this research was to investigate the effects of irrigation frequency and substrates on yield and fruit quality of greenhouse tomato (CV. Hamra). Irrigation was carried out for 4, 8 and 12 times a day. The substrates were Perlite, Leca and Perlite + Leca (1:1, w/w). The experimental design was factorial in the form of randomized complete design with four replicates. The substrates used in the experiment had no effect on most factors. However, TA (0.43 mg/100 l) and fruit set (48%) were increased significantly by perlite and Leca substrates, respectively. The results indicated that higher and lower marketable yields were obtained from plants irrigated 12 (1830.5 g/plant) and four times (1156.7 g/plant) per day, respectively. Also increasing irrigation schedule decreased the Titratable acidity but didn't significantly affect the other factors. According to these results, Irrigation of 12 times per day and Leca substrate increased vitamin C and marketable yields, leading to optimum quality and quantity fruit set and the decreased TA (0.33 mg/100 l) in fruits in this treatment.

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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

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Application of conceptual hydrological models is an important issue in watersheds for researchers, especially in arid and semi-arid regions. The hydrological behaviors are complicated in such watersheds and their calibration is more difficult. In this article, the conceptual and semi-distributed SWAT model is used for a semi-arid Nishabour watershed with 9350 km2 area. Streamflow simulation is considered for 8 years. Nishabour watershed modeling led to 22 subbasins and 146 Hydrologic response units. SUfI2 approach is used for calibration and uncertainty analysis of watershed modeling. Results showed that calibration and validation of watershed model is not satisfactory, because of uncertainties in conceptual model such as dam structures, and land subsidence. Another reason is related to the complexity of hydrological system in arid regions which has simplified in hydrological models. Moreover, the complex behavior between runoff and subsurface flow in low depth of rainfall events usually effects in hydrological simulation results. Finally, it concluded that we cannot rely on conceptual hydrologic models with different sources of uncertainty without including them in hydrological modeling at arid and semi-arid watersheds.

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Quantitative evaluation of evapotranspiration on a regional scale is necessary for water resources management, crop production and environmental assessments in irrigated lands. In this study, in order to estimate ETo and because of few synoptic stations and also little recorded meteorological data in North Khorasan Province, Iran, with arid and semi-arid climate, 7 stations from neighboring provinces were used. Reference evapotranspiration was calculated using 6 different methods which required a small amount of input data, including Class A pan, Hargreaves-Samani, Priestly-Tailor, Turc, Makkink and the method proposed by Allen et al (1998) to estimate ETo with missing climate data. Besides, the standard FAO-Penman-Monteith was used (because there was no Lysimetric data in the region) to evaluate the applied formulas. Since there was no agreement over the appropriate method to calculate ETo in the selected stations, by using significance test of regression lines, a linear regression equation was computed for each month, in order to convert the best calculating method to FAO-Penman-Monteith formula. Evaluations of these equations showed their acceptable accuracy, in comparison with the previous researches, specifically for cold months (MAE values ranged from 0.3 to 1.4 mm/day).