JOURNAL OF WATER AND SOIL RESOURCES CONSERVATION
Year:2019 | Volume:9 | Issue:1 |Papers Count:9

Organic amendments are used in soils, with a goal of improving soil properties such as fertility and nutrition. This study was conducted to evaluate and compare the effect of vermicompost, on the phosphorus (P) isotherm, phosphorous buffering capacity (PBC) and standard phosphorus requirements (SPR) with more commonly used sheep manure, poultry manure and grape waste in five vineyard calcareous soil of Malayer area in Hamadan province. Organic amendments were added to soils at the rate of 2 % and the samples were incubated for one month at 25± 2 ᵒ C and field capacity. Isotherm experiments in treated and control soils were carried out by concentrations of P ranging from 0 to 200 mg kg-1 of KH2PO4 in the presence of 0. 01 M CaCl2. Phosphorus sorption curves were well fitted to the Freundlich and Van-Hay equations. Incorporation of organic amendments increased soils available P, and decreased Kf constant, PBC and SPR in treated soils. The SPR average of control soils were 17. 1 mg kg-1, while in treated soils ranged from 9. 3 to 14. 5 mg kg-1. The PBC average of treated soils, with vermicompost, sheep manure, poultry manure and grape waste decreased 41. 0, 37. 9, 29. 9 and 21. 6 % than PBC average of control soils, respectively. The results indicated that conventional soil amendments such as sheep manure and poultry manure in vineyard soil can be replaced with vermicompost, an organic fertilizer with low salinity and natural pH which increases P availability in soil. We suggest further studies on P leaching from vermicompost treated soils.

Water repellency is one of the important physical properties of soil that affects the soil moisture curve, hydraulic conductivity, and so on. The aim of present study is to investigate the effects of adding natural and artificial biochars on water repellency and some other physical and chemical properties of soil. This study was conducted in factorial design with various levels of additives (natural and waste compost biochars) in a randomized complete block design in three repetitions. The considered factors are natural biochar in four levels (0, 1, 3 and 5%) and municipal waste compost biochar in four levels (0, 1, 3 and 5%) with the total of 16 treatments. The water repellency of natural and municipal waste compost biochar was measured by means of the water drop penetration time (WDPT) test and the actual time required for infiltration (tp ) was recorded for each 16 treatments. The results showed that increasing the percentage of applied biochars increased. The highest amount of tp belongs to treatments No. 5 and 16 were 156 and 170 s, respectively, which increased by 98 and 99 times in comparison with the control treatment. 12 of 16 treatments were classified as wet table or non-waterrepellent soil, one treatment in slightly and three treatment as strongly water repellent soil. In general, it can be said that application of biochars, especially the natural biochar, in terms of water repellency does not cause any infiltration problem. Also, it can be concluded that bulk density had an average decrease rate of 4. 3% and organic matter and pH had an average increase of 2. 2 and 1. 8 percentage respectively.

Water and nitrogen are the main factors limiting the maximum yield Achievement. Application of nitrogen fertilizer has great impact to increasing agricultural production. On the other hand, the high use of these fertilizers is due to the low efficiency of these fertilizers. This research was conducted in response to the challenges of water scarcity and inappropriate management of nitrogen utilization. To quantitate the reaction of the plant and calculate the water and fertilizer efficiency, two irrigation levels, full irrigation (I1) and deficit irrigation equal 30% (I2) as the first factor and two nitrogen levels of 200 (N1) and 160 (N2) kg per hectare, it was considered as a second factor. Experiments were carried out as field treatments and in lysimeters as a factorial in a completely randomized block design with three replications. The cultivars used were maize hybrid 611 and 704 mediator SC, which were cultivated in two seasons of spring and autumn, respectively. Based on the results of this study, leaf area index with higher nitrogen application in the same moisture conditions is increased. Nitrogen increase, while that enough water is available to the plant, increases the weight of 1000 seeds, grain yield, biological yield and harvest index. Optimum use of water and nitrogen fertilizer increases grain yield and therefore increases water use efficiency. With increasing nitrogen content, nitrogen use efficiency decreases in corn cultivation. Under stress conditions, with increasing nitrogen consumption, fertilizer N-recovery efficiency is also reduced by decreasing the absorption of this element by the plant. The economic and biological efficiency of water use in autumn cultivation was more than spring cultivation. Low spring yield and high rainfall during autumn crop period were due to the efficiency and more productivity of water use in autumn cropping. In Khuzestan weather conditions, the use of early cultivars is recommended instead of the mediator for spring crop due to coincide the pollination time with intense heat.

The aim of this study was to study the effect of landform and geological formations on some physico-chemical properties of soils in order to better identify the soil in order to optimize land management and promote the sustainable agriculture of the southern part of Orumieh Plain with an area of 35000 (ha) in West Azarbaijan province, Iran. In this research, satellite images, aerial photographs, topographic and geology maps were used to identify and distinguish different forms of land. Separation of soil series were carried out based on geomorphologic and geophysical methods. 40 soil profiles were drilled and described in standard dimensions. Five soil profiles were sampled every genetic horizon and transferred to the laboratory. The moisture and temprature regime of the soils were determined as Xeric and Mesic. Soils of the studied area were classified as Inceptisols and grate subgroups of Fluventic. The most dominant formations in the Barandoz and Ghasemlou river catchment were limestone, and lime is one of the determinant factors in the formation of rocks at different soils in the study area. On the other hand, physiography and topography have also played a significant role, so that the upper terraces have more developed soils and some sloping regions had young and less evolved soils. With decreasing height and proximity to Lake Urmia, the effect of groundwater level and its salinity on the profiles is evident. In the meantime, the margin of the rivers due to the sediments of the present age have young and uncoated soils.

Regarding the development trend of pistachio gardens in many provinces and the severe shortage of water resources in these areas, the supply of water requirement of pistachio is not feasible. In order to optimize management in water shortage conditions, it is necessary to evaluate the different levels of water supply during pistachio growth stages. The purpose of this study is determine the water supply status at different stages of pistachio growth using satellite images and SEBAL algorithm in Sirjan Plain. The actual evapotranspiration of pistachios was estimated using the SEBAL algorithm and Landsat 8 images. The result of this model was validated with Landsat 7 images. This model could calculate actual evapotranspiration of pistachio the same as other research with 20% error (0. 6 mm/day). The results showed that supply of water in the third stage of growth (at the peak consumption) due to increased pistachio water requirement, insufficient water supply led to 30% deficit irrigation in Sirjan plain. In order to better irrigation management, production can be increased by reducing irrigation in the second stage and increasing irrigation in the third stage. The rate of deficit irrigation in the Sirjan Plain was 17% and it was in the tolerable threshold for the pistachio. The results show that the pistachio tree is resistant to deficit irrigation (up to 26%) in low salinity levels. In high water salinity (4000 μ mho / cm), the effect of deficit irrigation and salinity is combined and pistachio production is rapidly reduced due to deficit irrigation.

Nowadays, using superabsorbent polymers such as pumice is one of practical approaches to increasing water storage in soil and increasing irrigation efficiency. To investigate the effects of pumice on chemical and physical characteristics of soil, growth parameters and irrigation schedule of onion, an experiment in CRD design as factorial with three factors including: 1) soil type (with two raters: a) sandy loam and b) clay loam, 2) irrigation schedule (with two rates: a) 7 and b) 4 days) and 3) pumice (with four rates: 0, 2. 5, 5 and 7. 5 percentage by weight) and three replications was conducted. Results showed that increasing pumice rate could increase bulb dry matter, bulb diameter and bulb height. Pumice also could increase seales number in bulb, p and K concentration in plant and also available P and K concentration and CEC in soil. Pumice application in both soils, increased soil salinity, but in none of soils, soil EC was not more than 5 dS/m. Pumice application in both soils could decrease soil pH and compaction significantly. There was no significant difference between 5% and 7. 5% of pumice rates, in bulb dry matter in sandy loam, height and diameter of bulb in clay loam, P and K concentration of onion and soil, CEC, compaction, salinity in sandy loam and drainage salinity. Between irrigation rates was no significant difference in none of properties, in treatments that received pumice. It can be concluded that using 5% pumice in soil, we can increase irrigation schedule of onion from 4 to 7 days.

The quantitative and qualitative decline of groundwater in recent years has needed for proper management of water from these valuable resources. One of the important ways to achieve this goal is to monitoring groundwater quality. In the present study, 12 water quality parameters related to 63 wells in Ardebil plain were measured in June and September (dry and wet season), 2013-2012, then water quality indices were studied. After calculating the indices, the ArcGIS10 software were used to prepare the maps and then calculate some important statistical parameters. The results showed that groundwater in Ardebil Plain with EC and SAR indexes average, 405. 17 microseisms per cm and 2. 8 in the C3-S1 class, according to Wilcox classification, and had a low to moderate limit Salinity and without any limit in term of penetration in the soil. RSC, KR and PI Indicators, which express the risk of sodium, indicate that there is no sodium constraint and have a good quality. The CR index with 0. 8 average also indicated a lack of groundwater corrosion risk. Investigating the Na and Cl also indicates an average limit for water toxicity for the plants cultivated in Ardebil plain. On the other hand, the zoning maps of the studied indices showed that salinity in some parts of the plain has a low to moderate limit, and in eastern and southern parts, it has no limitation. According SAR index most part of plain was unlimited, with only a small portion of the southern plain with moderate constraints. The LSI index showed that in most plain areas, the value of this index is greater than zero, and therefore there will be a risk of droplets.

To study the effect of different methods of partial root-zone drying irrigation and plant density on yield and water productivity of forage corn a field experiment was carried out in split plot arrangement using randomized complete block design with four replications at soil and water research institute, Karaj, Iran in 2014-2015 growing year. Different irrigation methods in three levels: I1: conventional furrow irrigation, I2: intermittent alternate furrow irrigation, I3: the fixed alternate furrow irrigation that were located in the main plots and plant density in three levels: D1: 75000 plants per hectare, D2: density of 85, 000 per hectare, D3: density of 95, 000 plants per hectare that were located in the sub plots. Results showed that the highest water productivity of Grain yield was achieved in treatment of the intermittent alternate furrow irrigation which showed 21. 6 % significant increase in comparison to conventional furrow irrigation. Generally, method of intermittent alternate partial irrigation was a significant advantage compared to other irrigation methods in order to increase water productivity. The highest water productivity for biological fresh yield (11. 97 kg. m-3) and WP for biological dry yield (3. 91 kg. m-3) was achieved in treatment of the intermittent alternate furrow irrigation and density of 85, 000 plant per hectare that increased 27. 2% and 31. 2% as compared to control treatment, respectively. Thus, method of partial root-zone drying irrigation (intermittent alternate) and density of 85, 000 plants per hectare to increase productivity of forage corn is suggested in Karaj area.

Accurate planning for adaptation to climate change is very important in each region. In this study, using the meteorological data of the six synoptic stations in the Ghezel Ozan basin in the period 1989-2016, and by employing the four GCM models, under the two scenarios RCP4. 5 and RCP8. 5, data were generated for the horizons 2050. Then, some parameters such as the air temperature, precipitation, potential evapotranspiration (ET0), precipitation deficit (PD) during the growing season, dryness intensity were calculated. ET0 was calculated by Pristeley-Taylor (PT) and Penman-Monteith (PM) methods. Then, ET0 obtained from the PT method was calibrated using four Artificial Intelligence methods (namely Eureqa Formulize, ANN, ANFIS and SVM) with PM method for each station. For spatial analysis, three geostatistical methods namely IDW, Kriging, and Cokriging were utilized. The results indicated an increase of 0. 9-2 º C in mean air temperature and an increase in precipitation between 27 and 49 mm will be experienced in the future period. Furthermore, ET0 and dryness intensity will be increased at all the stations. The increase in average PD (in the whole basin) will be about 6% to 9%. In average, the rate of increase in agroclimatic indices in the RCP8. 5 scenario will be about four percent more than the RCP4. 5 scenario. Among the methods of interpolation, the modified Cokriging based on DEM (Digital Elevation Model) showed the more suitable one among others. The length of the growing season will be elongated from 15 to 35 days. No significant changes will be occurred for dryness period. The spatial variation of future climate variables is expected to be not changed comparing the base period.