Journal of Soil Management and Sustainable Production
Year:2016 | Volume:5 | Issue:4|Papers Count:11

Background and Objectives: Application of various composts has been intensified in agriculture, due to manifestation of negative effects of chemical fertilizers on environment and soil fertility. However, their usage should be accompanied by environmental and nutritional studies. To produce maximum yield, most farmers apply nitrogen fertilizer more than the recommended level, which leads to increase production costs, water pollution and the environment. Therefore, proper management of this element due to resource constraint and also due to its high cost, as an input in agriculture, is one of the most important factors in the success of crop production and soil management. Wheat is a very important strategic crop which wide area of the world is assigned to cultivate it each year. The optimal use of fertilizers can lead to significant savings in production costs and preserve the environment. The aim of this study was to evaluate the effect of organic fertilizer, chemical and combination of them on wheat cultivars (N8019 and Darya) to reduce consumption and increase the efficiency of chemical fertilizers.Materials and Methods: In order to study the effects of sulfur granular compost on yield and yield components of two wheat cultivars, a pot experiment was conducted in a completely randomized factorial design with four replications. The first factor was consisted of three levels of nitrogen (0, 25 and 50 mg/kg of soil as urea), the second one was four levels of compost (0, 5, 10 and 15 g/kg of soil) and the third one was cultivars (Darya and N8019).Results: Results showed that the maximum number of grains per spike, spike weight, 100-kernel weight, straw yield and biological yield were obtained in 25 mg N/kg of soil treatment.Conclusion: The greatest grain yield, dry weight and harvest index were achieved with 50 mg/kg nitrogen. Negative effects were observed in the compost-treated plots, so that the maximum spike length and weight shoot dry weight, straw and biological yield were found in the zero level of compost (control) which showed a decrease in the mentioned variables with increasing the compost level. Negative response of wheat to the compost is likely related to the C/N ratio and probably to increase the solubility of heavy metals and/or toxic compounds that resulted in reduce or prevent soil biological activities. Both cultivars showed a positive response to the nitrogen treatment. N8019, however, was significantly superior to Darya.

Background and Objectives: Nowadays, the use of organic wastes in agriculture system is an important issue for both soil conservation and residual disposal. Municipal waste compost is a valuable source of some macro and micro nutrients and organic matter that enhanced different crops yield such as wheat, soybean and canola. Furthermore, application of Trichoderma fungus species can improve plant growth and development in addition to increases in biomass, biotic and abiotic stresses resistance and nutrient absorption. Therefore, the current experiment was aimed to evaluate the municipal waste compost and Trichoderma species fungi efficacy on seedling emergence parameters, growth and some micronutrients uptake of garden cress (Lepidium sativum L.).Materials and Methods: The experimental arrangement was factorial in a randomized complete block design with three replications in plastic pots (15 cm diameter). Treatments consisted of three levels of municipal waste compost (15, 30, 45 Mg ha-1 alone and plus 50% chemical fertilizer), recommended chemical fertilizer (100 kg ha-1 of urea, potassium sulfate and triple super phosphate) and a check (no compost or chemical fertilizer application) and three Trichoderma species (viridae, harzianum and hamatum). Trichoderma spores were adjusted in 108 mL colony forming units for 1 kg/soil dry weight. Some growth characters such as plant height, root length, fresh and dry matters of root and aerial parts were recorded 35 days after sowing. The root and aerial part samples were washed with distilled water and oven dried at 65oC for at least 2 days. The extract of plant ashes (0.5 g) was prepared with 2.5 CC of HCl (38%) and further diluted to 50 cm3. Then, micronutrient concentrations (Fe, Zn, Cu and Mn) were determined by Atomic Absorption Spectrometry. The statistical analysis of experiment data was performed by using SAS software and mean comparison of evaluation traits was done by least significant difference (LSD) method at 5% level of probability.Results: The results showed that application of 15 Mg ha-1 enriched compost and inoculation of soil with T. harzianum fungous promoted final emergence percentage, field emergence rate and cumulative emergence rate. In the current experiment, the 30 and 45 Mg ha-1 enriched municipal waste compost increased fresh and dry weight of aerial part (up to 21%) and plant height and root length (up to 16%) as compared to chemical fertilizer alone. Also, T. harzianum fungi increased fresh and length of plant root (20 and 5.30%, respectively) compared to T. viridae. The mean comparisons of fertilizer and Trichoderma interaction effects on plant tissue micronutrient content indicated that the maximum Mn content belonged to 15 and 30 Mg ha-1 municipal waste compost (enriched and non-enriched) inoculated with T. hamatum and the highest plant Fe content was observed in co-inoculation of 45 Mg ha-1 enriched compost and T. hamatum.Conclusion: In conclusion, application of 40 Mg ha-1 municipal waste compost markedly improved the quantity and quality characters of garden cress compared to the chemical fertilizer treatment. Also, Trichoderma species had different efficiencies on the studied parameters, so that T. harzianum specie showed superiority in seedling establishment, growth parameters and plant quality compared to the T. viridae.

Background and Objectives: Soil pollution with heavy metals because of its damaging effects on the environment, including human health threat, toxicity in plants and long-term effects on soil fertility have become a global concern. Lead is the most common heavy metals in polluted areas that enter to ecosystems, plants and the food chain from various sources. As a nonessential element for plants, lead inhibits not only photosynthesis, changes enzyme activities, hormonal status and respiration but also plant growth, metabolism and mineral nutrient balance. It has been demonstrated that heavy metals, like lead, can significantly influence the uptake and translocation of some nutrients in plants. Thus, the imbalance of nutrients might be a symptom of heavy metal toxicity in plants. Thereby, interactions between lead and mineral nutrients may provide a specific insight into the role of mineral nutrients in lead accumulation and translocation in plants. Iron is the micronutrient most often found to be deficient in plants. Among the nutrients showing interactions with heavy metals, Fe is one of the most frequently concerned in many respects. Heavy metals influence Fe availability and adsorption in the root apoplasm, uptake into root cells, transport to the shoot and utilization in leaves. In turn, Fe deficiency may also modify heavy metal uptake and accumulation. The objective of this study was to investigate the interactive effect of iron and lead on cress (Lepidium sativum L.) growth.Materials and Methods: For this, a factorial pot experiment in a completely randomized design with three iron levels (0, 20 and 40 mg kg-1) and three lead levels (0, 500 and 1000 mg kg-1) was carried out in triplicate. Lead and iron treatments were applied from lead nitrate and iron sequestrene-138 sources, respectively.Results: The results showed that shoot fresh and dry weights, SPAD value, Fe content and uptake and lead translocation index of cress decreased with the increase of lead content in the soil (P£0.01), but the lead content and uptake increased (P£0.01). The increase of soil iron content significantly increased the shoot dry weights (P£0.01), SPAD value and iron content and uptake (P£0.05) and caused a significant decrease in the lead content, uptake (P£0.01) andtranslocation index (P£0.05). Interactive effect of iron and lead indicated that iron application along with lead significantly increased the shoot dry weight of cress (P£0.05) and significantly decreased the lead content and uptake of cress (P£0.05).Conclusion: Iron plays an important role in reducing the adverse effects of lead in the cress. Hence, Applying 40 mg kg-1 of Fe as iron sequestrene-138 to reduce the adverse effects of lead on the cress is recommended.

Background and Objectives: Among the factors that control organic matter content of soils used for agricultural production, crop rotations and management practices are under the control of a manager. Tillage is one of the management tools, which can be defined as a modification of soil structure resulting from the operation of mechanized implements. Soil quality is governed primarily by the tillage practices used to fulfill the contrasting soil physical and hydrological requirements. Different tillage management could affect crop yield because of their effects on water conservation and soil chemical and physical properties. According to the cause, this study was carried out in order to investigate the effect of different tillage methods on wheat yield and soil physical and chemical properties in wheat - fallow rotation, in station of Ghamloo (Kurdistan).Materials and Methods: This experiment was conducted by randomized completed block design with 4 replications and 5 treatments in 2 phases for 3 years since 2004. The tillage treatments were: chisel plow in fall +sweep in spring (A1); non moldboard plow + sweep in spring (A2); no tillage in fall + Herbicide in spring (A3); no tillage in fall + sweep in spring (A4); check (Moldboard plow in spring) (A5). In all treatments, variety of Azar 2 with grain drill was planted equally. Also, in order to determine the effects of tillage methods on some physical and chemical properties of soil and plant, measurements were performed.Results: The results of combined variance analysis revealed that the wheat yield and components in different years were different due to the difference in rate and distribution of precipitation and cold weather in different years. The product yield in the first year (1963 kg ha-1) was the highest. Effect of tillage treatments on wheat quantity and quality and also yield components was significant, so that, the highest amounts of almost measured factors, obtained from treatment (A3).Conclusion: Based on the results of the investigations, for obtaining higher product quantity and quality of dryland wheat in the study region, it is suggested to apply no-tillage + herbicide in spring system.

Background and Objectives: Phosphorus (P) deficiency is frequently reported in many regions of the world, certainly in calcareous soils of arid and semi-arid regions. In calcareous soils, the soluble P is rapidly converted to insoluble precipitates of Ca-phosphates due to high content of CaCO3. Soil organic phosphorus (SOP), which can comprise up to 80% of the soil P, plays a significant role in P nutrition of crops specially in high P fixing calcareous soils. Soil organic P is a heterogeneous mixture of organic substances and the different fractions of SOP might have different effects on soil fertility and quality. Organic amendments such as sewage sludge and animal manures can be recycled to agricultural lands as a source of organic matter and phosphorus. Organic amendments may influence P dynamics in soils. This study was conducted to investigate the short-term (100 days) effects of some organic amendments on the soil organic P (SOP) fractions and their availability to wheat in a calcareous soil.Materials and Methods: A calcareous soil, which suffer from P deficiency, was collected in summer 2013 from Kerman province, air-dried, crushed and transferred to pots including two levels of sewage sludge (SS), cow manure (CM), poultry manure (PM) and no organic amendment (CO) in four replicates. Four wheat seeds were sown in each pot and kept for 100 days in a controlled greenhouse. At harvest, shoot dry weight and shoot P concentration were measured. Soil organic P fractions including labile organic P (LOP), moderately labile organic P (MLOP), moderately non-labile organic P (MNLOP) and non-labile organic P (NLOP) was also measured.Results: Soil application of organic amendments significantly increased shoot dry weight and shoot P uptake of plants. The highest values were found in soil amended with 4% level of sewage sludge. Organic amendments markedly (P<0.05) increased all organic P fractions compared with the control. Moderately labile organic P was affected by organic amendments more than the other fractions. Regardless of applied levels, the magnitude effect of organic amendments on different OP fractions was ranked in the following order: SS>CM>PM. A significant correlation was observed between labile organic P with soil available P (r=0.92**), P uptake by wheat (r=0.92**) as well as between MLOP and shoot dry weight (r=0.96**), showing that labile and moderately labile organic P fractions have more contributors to available P than the others.Conclusion: These results suggest that adding of organic amendments can increase P availability and plant growth due to increase in soil OP fractions especially labile and moderately labile organic P fractions.

Background and Objectives: One of the outcomes of the industrial development has been the increase in CO2 levels in the atmosphere from 280 to 367 Microliter per liter by the end of 20th century. Many studies have investigated the effects of increasing CO2 levels on plant. Increase in atmospheric CO2 levels and increasing concentration of heavy metals in agricultural lands can effect plant growth, production and have negative impact on human health through food chain. This study was aimed to investigate the effects of different levels of CO2 and cadmium on growth and cadmium uptake by wheat and sorghum.Materials and Methods: A greenhouse experiment was carried out with pots containing 3.5 kg soils and in split factorial design. Treatments included four levels of cadmium (0, 10, 20 and 40 mg Cd kg-1 soil) (from Cd (NO3)2) and two levels of CO2 (400 and 900 mL L-1). Cadmium uptake by plants roots and shoots and phytoremediation indices were calculated for both plants.Results: The results indicated that increasing CO2 levels, enhanced maximum shoot and root dry weight by 26% and 17% for wheat and 18% and 13% for sorghum, respectively. Increasing CO2 levels did not have any effect on Cd uptake by wheat but increased Cd uptake by 37-44% in shoot and 26-37% in root for sorghum. Phytoremediation indices were calculated based on the effect of increasing CO2 level on plant dry matter and Cd uptake. Although, Bio Concentration Factor, Biological Accumulation Coefficient and Tolerance Index were all less than unit, but with increase in CO2 levels these indexes and Remediation Ratio increased for sorghum.Conclusion: Since the increase on CO2 concentration increased cadmium uptake and remediation ratio in sorghum, this plant has a higher potential for extracting cadmium from polluted soils, specially in areas where increase in CO2 levels are an issue. This can be important in industrial areas and the agricultural lands around them. The interactions between soil cadmium and increasing CO2 levels in the atmosphere with respect to climate change requires further research to study its effect on various plants.

Background and objectives: Among various nutritional requirements for production, nitrogen is known to be an essential element for plant growth and development. Nitrogen deficiency limits cell division, chloroplast development, enzyme activity and reduces dry matter yields. Although nitrogen is the key element in increasing of productivity, but large rates of fertilizer N loss to the environment could cause a serious environmental problem such as groundwater contamination. Chemical fertilizers combined with organic manures result in increase of soil organic matter, improvement of soil properties and increase of crop yield. Determination of the effects of Azotobacter, Azospirillum and Psedomunas inoculation and spraying time of nitrogen on fertilizer use efficiency and growth of triticale is very important to maximize yield and economic profitability of triticale production in a particular environment. Moreover, it seems that there is little investigation about the combined effects of nitrogen fertilization and bio fertilizer on growth of Triticale. Considering the above facts, the present study was performed to know the effects of Azotobacter, Azospirillum and Psedomunas inoculation and spraying time of nitrogen on fertilizer use efficiency and growth of Triticale.Materials and methods: A factorial experiment was conducted based on randomized complete block design with three replications in research farm of the Faculty of Agriculture, University of Mohaghegh Ardabili in 2012. Treatments were: seed inoculation with plant growth promoting rhizobacteria in four levels containing (without inoculation as control, seed inoculation with Azotobacter chroococcum strain 5, Azospirillum lipoferum strain OF, Psedomunas putida strain 9 and spraying nitrogen fertilizer in four levels (without spraying as control, spraying in boot stage, ear emergence, grain filling period) from urea.Results: Results indicated that spraying of nitrogen fertilizer × seed inoculation with PGPR had significant effects on growth indices, yield and yield components at 0.01 probability level. The highest values of total dry matter, crop growth rate and relative growth rate and leaf area index were observed in inoculated plants with Azotobacter chroococcum × nitrogen spraying in boot stage and the lowest were recorded in non-seed inoculation and without spraying. Maximum of yield and yield components, fertilizer use efficiency were obtained in seed inculation with Azotobacter chroococcum × nitrogen spraying in boot stage.Conclusion: It seems that in order to increase these traits, is suggested nitrogen spraying in boot stage × seed inoculation with Azotobacter.

Background and Objectives: Heavy metals added to an aquatic system by natural and anthropogenic sources during their transport, are distributed between different compartments of ecosystems such as water and sediment. Measurement of bioavailability and mobility are required in order to understand the behavior of heavy metals in sediments and to prevent potential toxic hazards. Metals are introduced into aquatic environment from various sources and accumulated in sediments. The distribution of metal along route of rivers is also different. Distribution of metals in bioavailable fractions make them more susceptible to be released to water.Material and Methods: Seventeen surface sediment samples were collected from 0-10 cm depth of rivers Abshineh and analyzed for total and bioavailable concentrations of zinc (Zn), cadmium (Cd), nickel (Ni), copper (Cu) and lead (Pb). Abshineh River is the major source of drinking water for Hamadan city and many urban, agricultural and industrial areas active along the river.Results: Downstream sediments have lower clay, calcium carbonate equivalent and organic matter in comparison with upstream sediments. Average total (± Standard Deviation) Zn, Cd, Ni, Cu and Pb concentrations of the sediments were 93.08±20.66, 1.24±0.63, 57.72±13.08, 19.23±7.62 and 52.47±8.52 mg kg-1, respectively. The sediments were polluted with respect to Cd and Pb to some extent. Total metals concentrations were correlated with sediment physical and chemical properties. EC, organic matter, CEC and clay were sediment parameters that showed significant positive correlations with total heavy metals concentrations indicating that heavy metals concentrations are controlled by sediments grain size. Sediments of Abshineh River were polluted with respect to cadmium to some extent. Sediments in upper reach was not polluted by metals, while in lower reach the concentration of metals increased and reached to pollution especially regarding cadmium and lead. The majority of metals had strong bonding with sediment components indicating their low bioavailability to organisms.Conclusion: There is a highly significant correlation exist between bioavailable and total Zn and Cu which can be due to the common sources of introduction to the river. Percent of DTPA-extractable Cd was much higher than the others, which suggests that possible mobility of this metal from exchangeable phase. The bioavailability of the five studied metals from Abshineh probably decline in the following order: Cd>Cu>Pb> Ni=Zn. Cadmium and Pb had higher bioavailability in comparison with other metals suggesting that these metals were distributed in non-labile fractions of sediments.

background and Objectives: Soil survey, mapping and evaluation studies has long been characterized by tension between the recognition that soils or soil properties vary continuously across the landscape and the necessity in soil classification of defining discrete entities. On the other hand, soil classes are usually separated by arbitrary threshold values for soil properties. In this regard, uncertainty will be an integral and attached part to phenomena, data and spatial information. Therefore, each soil mapping project has some deficiencies and uncertainties associated with incomplete and imperfect field measurements and limitations of soil cartographic representation. This paper is concerned with the concept of taxonomic adjacency and pedodiversity to compare the potential variability and uncertainty associated with arbitrary classification boundaries or thresholds in taxonomic criteria of both Soil Taxonomy and WRB systems.Materials and Methods: After preparing the primary interpretative map (1:50,000 scale) for part of the Lalehzar region (Kerman province), based on the geopedologic approach, separated unit boundaries on the map were controlled and corrected in the field according to the semidetailed soil surveys. Then, soil profiles were dug in each of the geomorphic units and finally 20 soil profiles were described and sampled in the study area. After necessary physical and chemical analyses on the samples, soils classification was finalized based on both Soil Taxonomy (2010) and WRB (2007) systems. Afterwards, based on the separated soil classes in both mentioned classification systems, the taxonomic adjacency matrix of studied soils were prepared using algebraic graph theory. Then, the largest eigenvalue of the matrix (the spectral radius) was used for calculating taxonomic adjacency index of soil map of the region. Besides, the diversity of the soils of the area was calculated using Shannon diversity index and is compared with the taxonomic adjacency index.Results: Results showed that according to the Soil Taxonomy system, soils of the area were in three Entisol, Inceptisol and Alfisol orders; however, based on the WRB system, Regosol, Cambisol, Calcisol and Luvisol reference groups were the dominant soils of the area. Besides, Soil Taxonomy criteria have greater degree of uncertainty in the classification of the soils of the studied area compared to the WRB system. Due to differences in the geomorphic units, the WRB system showed better the small amount of taxonomic adjacency in the soils of the area.Conclusion: Comparison of the taxonomic adjacency index results with those of the Shannon diversity index in showing the diversity of the soils indicated that the WRB system has acted more accurately than the Soil Taxonomy system. In general, the relationship between taxonomic adjacency and landscape was clearly visible in the study area.

Background and Objectives: Boron is one of the essential micronutrients required for plant growth. The concentration of boron in irrigation water or in soil plays an important role in both quality and quantity characteristics of plants. The optimal concentration range for boron is narrower than for other plant essential nutrients. If boron concentration becomes slightly higher than the necessary levels for growth, its toxicity symptoms appear on plant leaves. Knowledge about factors affecting boron adsorption by minerals commonly found in soils of arid and semiarid areas may help us in management and reclamation of boron polluted soils. The main objective of this study was to investigate the adsorption characteristics of biotite for boron in batch experiments.Materials and Methods: The adsorption of boron on the adsorbent was studied as a function of pH in the range of 6.5-9.0 with two boron concentrations of 5 mg L-1 and 15 mg L-1. To study the effect of cations and ionic strength on boron adsorption, Mg (NO3)2, Ca (NO3)2 and NaNO3 background electrolytes at three concentration levels (0.03, 0.09 and 0.18 M) were used. Adsorption isotherms were derived by adsorption of boron from solutions containing different concentrations in the range of 1-15 mgL-1 using a 24h batch equilibration. In order to interpret the adsorption behavior of boron, FTIR spectra of the adsorbent was recorded using FTIR spectrophotometer before and after adsorption experiments and species activities of boron were estimated using the Visual MINTEQ speciation program.Results: The results showed that the amount of boron adsorption increased with increasing equilibrium pH and ionic strength of solution. Boron adsorption increased from 1.28 mmol kg-1 to 2.64 mmol kg-1 as the ionic strength of solution increased from 0.03 M to 0.18 M. Greater adsorption was observed in the presence of Ca2+ and Mg2+ions as compared with Na+ ions at the same concentrations. It thus seems that the much greater loss of B from solution observed in the Ca system was caused by Ca-borate ion pair (CaH2BO3 + and MgH2BO3 +) adsorption. Adsorption isotherms of boron were well described by the Freundlich and Langmuir isotherms. Maximum boron adsorption capacity (qmax) of biotite was obtained to be 27.2 mmol kg-1.Conclusion: In general, the experimental data showed that less than 6% of initial boron concentration was adsorbed by biotite. Thus, it seems that this mineral does not have a reasonable adsorption capacity for B.

Background and Objectives: Nowadays the use of fertilizers and pesticides, mining, industrial and non-industrial waste disposal, results in the destruction of most important habitats i.e., the soils. In this regard, the presence of organic and mineral pollutants in the soil, is one of the challenges that human beings face. Lead has been of great importance in heavy metals and hazardous metals in the second rank and highly toxic effects on living organisms. Cadmium, another example of heavy metals due to its toxicity to humans and animals is of great importance from the viewpoint of the environment. Many studies about the relationship between the silicon and the tolerance of plants to heavy metals and the role of silicon in the modified biotic and abiotic stress have been done. This research project was performed to reduce the toxicity of cadmium and lead in spinach by silicon.Materials and Methods: In order to investigate the use of bio-refining of silicon on cadmium and lead in spinach, a pot experiment was done in Qaemshahr Agriculture University in 2012 as a completely randomized design with four replications. Treatment include silicon (150 mg/kg of Potassium silicon), Pb (100 mg/kg of chloride), Cd (100 mg/kg of chloride), silicon+Pb, silicon+Cd and control as used soil.Results: The results showed that the maximum concentration of lead in the shoots and roots (respectively 42.45 and 178.20 mg per kg dry matter) was obtained by taking the lead. The accumulations in the treatment of lead + Si (27.82 and 61.90 mg kg DM, respectively) were lower. The length of the shoots on the use of cadmium (14.06 inches) and a minimum length of root involving the use of lead (10.37 inches), decreased as 42.4 and 28.8 percent respectively. The lowest plant fresh weight of individual consumption of lead and cadmium and cadmium together with silicon consumption in comparison with control were 69.1, 69.2 and 65 percent.Conclusion: The results showed the impact on silicon consumption during the shoot and root compared to the control. It also reduces the accumulation of lead and cadmium zinc application in shoot and root, respectively.