mahmood fazeli sangani

Risk assessment is utilized to prioritize preventive measures based on the probability of dispersal success of pests. A main part of the risk assessment procedure is to determine the effects of environmental variables on the current and potential geographical distributions. In the present study, the spatial distribution of the Mediterranean pine engraver, Orthotomicus erosus (Wollaston), was mapped and predicted using MaxEnt. Presence records of O. erosus (north, northeast, west and centre of Iran), environmental and topographic variables, with the lowest correlations among themselves and the highest effects on the pest distribution were used. A total of 76 presence records of O. erosus were collected. The results of the distribution prediction modelling revealed that the northern part of Iran and the areas along the Zagros are the most suitable habitats for this species. Examining environmental variable importance on the distribution of O. erosus showed that the variables related to temperature and precipitation had more contribution in the MaxEnt model, respectively than the altitude. Furthermore, the high accuracy of the model (0.928) indicated that the MaxEnt had an acceptable performance for the prediction of O. erosus distribution. These findings would provide primary and critical information about the potential distribution of O. erosus in Iran, which could be effective for the stable population regulation of this destructive pest.

Carbon dioxide is one of the main greenhouse gases that affect the world's air temperature. Small changes in the amount of carbon dioxide emissions from the soil have a significant effect on the concentration of this gas in the atmosphere. Soil respiration, the process that emits carbon dioxide from the soil to the atmosphere, is one of the most important carbon flows in the ecosystem and includes two components of heterotrophic respiration (microbial respiration) and autotrophic respiration (root respiration). Researchers measure the rate of soil respiration for every 10 degrees Celsius of temperature change with an index called temperature sensitivity of soil respiration (Q10). The evidence shows that the Q10 value of the soil is not constant and has a negative correlation with temperature and a positive correlation with soil moisture. Also, the amount of soil organic carbon, incubation temperature and the interaction of these two have a significant effect on soil organic carbon decomposition. Accordingly, this research measures the temperature sensitivity (Q10) in soil under tea cultivation and investigates its relationship with some soil chemical characteristics and topographic indices.

After surveying the east and west tea gardens in Guilan province in the north of Iran, 200 samples were taken at a depth of 0 to 40 cm. The experiments were conducted to determine Organic Carbon, Labile carbon, Bulk density, PH, Cation Exchange Capacity, Microbial Biomass and soil microbial respiration. To measure Q10, two temperature treatments of 25 and 35 °C were used. Elevation, slope and aspect were obtained using a DEM map in ArcGIS 10.5 and other topographical indicators such as wetness index, slope length, relative slope position, catchment area, channel network base level, vertical distance to channel network, convergence index, profile curvature and plan curvature were extracted from DEM map in Saga GIS 2.1.0. Pearson correlation was used to investigate whether there is any relationship between soil temperature sensitivity with other soil properties. Then, principal component analysis (PCA) was performed to determine a minimal data set. All the statistical analyses were done with SPSS 24. Regression charts were also drawn using Excel software.

The Q10 values varied from 1.19 to 1.58. This index has the most negative correlation with organic carbon (-0.863), Labile carbon (-0.863), microbial biomass (-0.837), respiration at 25 °C (-0.831) and 35 °C (-0.8) at 1% level and negative correlation with elevation at 5% (-0.159). The principal component analysis showed that the first six components (PC1, PC2, PC3, PC4, PC5 and PC6) have special values of more than one and were able to describe 73% of the total variance. The first main component (PC1) describes 23.125% of the total variance and includes soil organic carbon, labile carbon, microbial biomass and Q10 which have the highest factor loading in this component. The second one (PC2), which explains about 12.99% of the total variance, has the highest factor loading with the vertical distance to the channel network (0.880). The third component (PC3) explains about 12.22% of the total variance. In PC3, clay has the highest factor loading. In the fourth component catchment area, convergence profile and slope length have the highest factor loading, respectively. Finally, the fifth and the sixth components are related to the elevation, slope and plan curvature.

The highest positive factor loading is related to soil organic carbon (0.981). Therefore, the first main component can be "part of the role of organic carbon in microbial biomass, labile carbon and temperature sensitivity". The results showed that Q10 has the highest negative correlation with soil microbial biomass and organic and labile carbon. In other words, the higher the soil organic and microbial biomass carbon, the lower the amount of Q10. Also, the second component can be considered as topographic indicators related to the channel network. Topographic indices can be used very strongly to model making soil organic carbon. The third component is related to clay properties. Several studies have indicated that the amount of clay has a high relationship with cation exchange capacity and it is a good indicator to determine the quality of soil. According to the results, although the correlation between some characteristics obtained from soil topographical analysis can prove the possibility of using them as auxiliary variables in predicting soil organic carbon, this point should be taken into account that other factors also play a role in the process of soil formation and development.

The Mediterranean pine engraver, Orthotomicus erosus (Wollaston) (Col.: Curculionidae: Scolytinae), is a destructive bark beetle in pine forests worldwide. Regarding the recent outbreak of O. erosus in Iran, its flight activity and population density were monitored in four contaminated sites in western Tehran. These four sampling sites included Tabiat Park, Khargush Darreh Forest Park, Chitgar Park behind Bam Riding Club as well as Chitgar Park 9th Aghaghiya Street (western Tehran). Two pheromone traps (ECONEX ORTHOTOMICUS EROSUS 60 DAYS pheromone, Spain) were installed in each sampling site at the height of 2.5 m in the south direction of the pine trees. The number of trapped adults was recorded at 10-day intervals from April 2019 to March 2020. In total, 8514 adults of O. erosus were collected using pheromone traps during the sampling period. The results showed that the adult flight started from April in four sampling sites. The flight periods of adults continued until November in Tabiat Park, Khargush Darreh Forest Park, and Chitgar Park, behind Bam Riding Club. Differently, the last adults were collected in October in Chitgar Park, 9th Aghaghiya Street. In addition, the flight peaks of O. erosus occurred in August in Tabiat Park, Khargush Darreh Forest Park, and Chitgar Park, behind Bam Riding Club. However, the highest number of adults were trapped in July in Chitgar Park, 9th Aghaghiya Street. Based on our results, the number of trapped adults was significantly different in sampling sites. The mean number of trapped adults was the highest (183.25 ± 0.11) in Chitgar Park, 9th Aghaghiya Street and lowest (106.32 ± 0.07) in Tabiat Park during the whole monitoring experiment. These findings on flight activity and population fluctuation of O. erosus in local conditions could be helpful to establish an efficient and successful management program for this destructive pest.

In kiwifruiy vineyards, the high concentration of bicarbonate ions in irrigation water or soil is one of the main limiting factors on growth and production. The high levels of bicarbonate in irrigation water caused soil alkalinity and reduced the root accessibility to nutrients such as irons. Iron deficiency in kiwifruit vineyards caused leaves chlorosis and therafter, fruits. Fruits with iron deficiency have an unacceptable taste and low shelf life. Iron deficiency is usually more severe in June and July with increasing irrigation frequency. Growing suitable rootstocks that have a high tolerance to soil alkalinity is a good strategy to overcome this problem. Therefore, in this study, the response of seedlings in different populations of kiwifruit from three different species to irrigation water bicarbonate was investigated.

In this study, the effect of different concentrations of bicarbonate ions in irrigation water (0, 170, 350, and 550 mg L-1) on leaf chlorosis and iron uptake of seedlings of six kiwifruit seed populations (Green 11, Bruno, Red 2, Red 6, Red 22 and Baby kiwi) from three different species (Actinidia deliciosa, A. chinensis and A. arguta) was investigated as a factorial experiment in a completely randomized design with three replications in research greenhouse of faculty of agricultural sciences, University of guilan. Each replication was one potted seedling. The plants were irrigated with different bicarbonate level for 6 weeks with three days intaervals. Traits such as leaf fall percentage, stem diameter, chlorosis percentage, necrosis percentage, chlorophyll a, b, total chlorophyll, carotenoids and iron content of leaves were measured.

The results showed that increasing bicarbonate concentration in irrigation water caused leaf abscission. The highest leaf abscission percentage was observed in Baby kiwi from A. arguta with 16.6% and the lowest one in Bruno (1.19%) from A. deliciosa species as compared to their control, when exposed to high bicarbonate stress. Genotype type, different levels of bicarbonate and their interaction did not show a significant effect on the percentage of stem diameter changes. The Red2 from A. chinensis species seedlings showed the highest leaf chlorosis (38.46%) and the lowest leaf chlorosis was found in Green 11 seedlings from A. deliciosa with 6.95%. With increasing the amount of bicarbonate in irrigation water, the percentage of leaf necrosis also increased. Total leaf chlorophyll and carotenoid content significantly declined in all genotypes with increasing bicarbonate ion content in irrigation water. With increasing bicarbonate ion concentration in irrigation water, leaf iron content significantly decreased. The lowest iron declining percentage compared to the control when seedlings exposed to 170, 350, and 550 (mg L-1) of bicarbonate of irrigation water was found in Bruno from A. deliciosa species with 3.28, 4.29, and 4.72%, respectively. Moreover, the results showed that there is a significant correlation between leaf iron content and chlorophylls content, chlorosis percentage and necrosis percentage.

Overall, because of low leaf abscission and higher iron absorption in Bruno seedlings when exposed to high bicarbonate concentration in irrigation water or soil cab be recommend as a souperior rootstock.

Organic matter is one of the most important factors affecting soil properties, and understanding its effect on potassium and calcium selectivity can help the management of these two essential nutrients. This study examined the effect of organic matter on potassium and calcium selectivity in a binary exchange system in soil with dominant illite mineralogy. Organic matter was added to soil at a rate of 2%, and then the soil was incubated for ten months. The experiment was performed at an ionic strength of 0.1 M using solutions with a different equivalent fractions of potassium (ẼK) and calcium (ẼCa) between 0 and 1. Then Vanselow (KV), Gapon (KG) and Davis (KD, n = 2, 4, 6) selectivity coefficients and thermodynamic parameters including exchange equilibrium constant (Kex) and free energy changes of the exchange reaction (ΔG°ex) were calculated using exchange data with and without considering the effect of calcium carbonate dissolution on exchangeable calcium values. Comparison of K-Ca exchange isotherms with non-preference isotherm (NP) showed that potassium was preferred over calcium up to ẼK≃0.8, before and after adding organic matter, however at higher ẼK, calcium was preferentially selected. All selectivity coefficients increased with increasing equivalent fraction of potassium in the exchange phase (EK), which indicates that these selectivity coefficients are not true equilibrium constants. Moreover, Kex was less than 1, and ΔG°ex was positive, indicating a preference for potassium over calcium by soil. Also, after the addition of organic matter Kex, increased, and ΔG°ex decreased, indicating a decrease in soil preference for potassium. In addition, results showed that considering the effect of calcium carbonate dissolution on exchangeable calcium value has a significant impact on selectivity coefficients and thermodynamic parameters of exchange in calcareous soil. This highlights the need to pay attention to the dissolution of calcium-containing minerals in the soil during exchange studies.

The development of an accurate for monitoring the soil moisture is very important step in soil and water conservation activities and studies. The purpose of this study is to provide solutions to optimally determine the number of sensors required to monitor soil moisture bases on geostatistical approaches and intelligent monitoring of the water status in soil. In this research, 87 samples were taken as a regular network from the surface depth (0-30) cm. Three levels of the samples number were considered. By decreasing the samples number, the estimation accuracy decreases and the component effect increases, that indicates an increase in the random and non-structural part of the property. With the high sample number, the fitness of the model was 1.2% and 2.7% more than when the average and the minimum sample number. Reducing the samples has increased the radius of effect and decreased the ratio of structural to non-structural variance of properties. So the radius of effect of field capacity when the sensors number is at its maximum level is 36.8% and 38.4% less than the other two levels, respectively. As the samples number decreases, the estimation error increases sharply. Based on the findings, the use of between 20 and 30 sensors per 100 hectares produced the best results. The kriging method was an excellent estimator for moisture mediation. The proposed method can be used in determining the optimal sensors number for irrigation planning.

Due to the importance of zinc in rice plant nutrition, the present study was conducted to determine the effect of waterlogging period on the amount of plant available zinc in acidic and alkaline soils separately based on a completely randomized design. Variation in distribution of different forms of zinc before and after waterlogging was also compared. Soils were submerged for a period of 90 days and then the parameters of Eh, pH and plant available zinc were measured at 0, 7, 15, 30, 45 and 90 days after waterlogging. Different forms of zinc were also determined using sequential extraction method. Generally, the amount of plant available zinc decreased in both acidic and alkaline soils during the waterlogging period. Submergence condition led to a significant decrease in soluble + exchangeable and organic forms of zinc, while at the end of the submergence period, the carbonate form of zinc significantly increased in alkaline soil. In both acidic and alkaline soils, no significant changes were observed in the form of zinc bound to manganese oxide, while the amount of zinc bound to amorphous and crystalline iron oxides increased and the amount of residual zinc significantly decreased. In general, the results showed that the concentration of zinc in waterlogged soils is mainly affected by the changes in various forms of iron. Furthermore, plant available forms of zinc decreased in waterlogged condition which can lead to zinc deficiency in rice plants. Hence, it is recommended that the amount of plant available zinc in soil should be managed via soil or foliare application of zinc fertilizers in a way that its decline during waterlogging period has less negative impact on plant yield.

Main portion of organic wastes usually is burned or left in fields or landfills, which leads to pollution of soil, water, and air. The use of organic wastes for biochar production can be considered as a solution for the above-mentioned problems. Biochar is a rich carbon material which is produced via pyrolysis of various biomasses in anaerobic or limited oxygen condition. Inspire of world attention to biochar application in soil, effects of particle size, and method of biochar application has also been studied in a few pieces of research. Biochar is mixed with surface soil without the selection of a given class of particle size in most researches. Furthermore, olive kernel is considered as the main waste in agro-industrial integration, which often has no special use and is left in nature. Therefore, the use of olive kernel as a feedstock for biochar production can be a great approach for the management of these wastes and improvement of soil quality. Therefore, the purpose of this research is: 1- biochar production of olive kernel and its characterization and 2- A study of biochar addition effects with different particle sizes as the suspension on soil physical and erosion related properties of an erosion- prune soil.

An erosion-prone slit clay soil was sampled as undisturbed via metal cylinders (diameter and height of 25 and 15 cm, respectively) from 0 to 10 cm of soil located at Rudbar, Southern of Guilan, Biochar was produced of olive kernel at 650 C○ and 2 hours and 45 minutes. Biochar yield was calculated based on produced biochar per unit weight of feedstock (olive kernel). pH and electrical conductivity of olive kernel was determined at 1:5 (olive kernel powder : water) and 1:20 (biochar : water). Carbon, hydrogen, and nitrogen content and Fourier Transform Infrared Spectroscopy of olive kernel and biochar were assessed through Elemental Analysis and Fourier Transform Infrared Spectroscopmeter, respectively. Biochar was milled, and with particle size of 53-250 and 250-500 micron at 1 and 2 weight percent as a water suspension was injected to cylinder containing undisturbed soil. Four cylinders without biochar was also considered as a control treatment. Soil cylinders were located at a greenhouse at 20-25 C○ for 10 months (300 days) and their moisture was held approximately at 70 percent of field capacity. At the end of the tenth-mont of incubation, samples were provided of cylinders, and some soil properties and soil loss were studied.

The studied soil had a silt clay texture. Containing an abundant amount of silt can increase sensitivity of soil to surface crust formation. Carbon and hydrogen content was increased and decreased 44 and 69 percent, respectively as a result of olive kernel transformation to biochar. Result of Fourier transform infrared spectroscopy also showed olive kernel transformation to biochar has led to decrease of volatile organic components and increase of carbon and nitrogen content.
Results of this study showed that biochar with coarser particle size (250-500 micron) led to more increase of hydraulic conductivity compared to ones with finer particle size (53-250 micron). Although, biochar application result in aggregate stability improvement and runoff production decrease, biochar with particle size of 53 to 250 and 250 to 500 micron had no significant difference compared to each other. Runoff delay time and sediment yield were more and less, respectively in all biochar treatments in comparison with control (without biochar). The most increase of runoff delay time (5.65 minutes) was also was observed at 2 percent biochar application level of 250 to 500 micron. Biochar with particle size of 53 to 250 and 250 to 500 micron result in more decrease of sediment yield at 1 and 2 percent biochar application levels, respectively.

Generally, the results of this research showed that the transformation of organic wastes such as olive kernel can be considered as a useful approach to manage this kind of wastes. Olive kernel biochar with having less hydrogen to carbon molar ratio compared to feedstock (olive kernel) has long-term persistence in soil.  Furthermore, olive kernel biochar application as a suspension in an erosion-prone clay slit has positive effects on improvement of aggregation and hydraulic conductivity, and potential erosion decline.  Therefore, biochar production of olive kernel and its application as a suspension not only prevent soil degradation in time of application in soil but also lead to long-term carbon sequestration, improvement of important properties influencing soil quality, and sustainable use of unused wastes. A Study of biochar particle size and application-level also showed a specific type of biochar does not exert similar effects on different properties of a given soil, and particle size and level of biochar application must prescribe according to the desired goal.

The aim of this study was to evaluate the removal of phosphate, nitrate and ammonium from Saravan landfill leachate by chlorella vulgaris. The effect of leachate on growth characteristics of chlorella vulgaris, including dry cell weight, chlorophyll and carotenoids content was also investigated. The experiment was performed as repeated measures in a completely randomized design with three replications. Leachate levels were considered as main plot (zero leachate (L0), diluted leachates of 1:1 (L11) and 2:1 (L21)) and sampling time (0, 2, 4, 6, and 8 days) as sub-plot. Total chlorophyll in L0 treatment was the maximum and in L11 treatment was significantly more than the one in L21 treatment (p < 0.05). Microalgae dry cell weight and nutrient removal increased over time, so that the highest amount of dry cell weight and the lowest amount of nutrients in leachate (L11) was observed at 8th day after incubation. The percentage removal of phosphate, nitrate and ammonium at the end of 8th day of incubation was 92.76, 56.94 and 98.70, respectively. The kinetic equation of biomass production was also determined in relation to phosphate, nitrate and ammonium removal. The results showed that the nutrient removal followed the first-order model, and Monod's equation was able to well describe the growth of microalgae under restricted substrate conditions. The R2 values of Lineweaver–Burk for phosphate and ammonia were 0.97 and 0.99, respectively. Therefore, this equation can be used to remove phosphate and ammonium. Finally, it seems that chlorella vulgaris can be used for bioremediation of Saravan leachate.

Addition of biochar to soil has been recently considered as an amendment to reduce soil erosion. Biochar contains pyrogenic carbon, which is produced by heating residue of various crops, woods (or in other words various biomass) in restriction or absence of oxygen. Biochar can affect soil organic matter level and aggregate stability. Reduction of soil erosion through maintenance and  the increase of organic matter, increase of aggregate stability and improvement of hydraulic conductivity, and enhancement of moisture retention as a result of biochar application should be considered as an important achievement. It is important to study the effect of the different methods of biochar addition to the soil. The method of uniformly mixing biochar with surface soil which has been used in most studies can disturb the natural structure and lead to soil degradation. Therefore, it is an important issue to introduce a practical method that is associated with minimal soil manipulation, especially in erosion-prone soils. The effect of the biochar addition as suspension in water has never been reported in previous studies. Therefore, the aim of this study was to investigate the effects of adding different levels of biochar produced from two types of feedstocks (horticulture and agriculture wastes) in form of aqueous suspension on the properties of two types of erosion-prone soils in southern Guilan.

Two erosion-prone soils which were undisturbed, were sampled by metal cylenders (diameter and height of 25 and15 cm, respectively) of marl lands located in southern guilan. These soils were named as SL and L. Texture of SL and L were sandy loam and loam, respectively. Two types of biochar were produced from different feedstocks including pruned branches of ash tree (Fraxinus excelsior) and rice husk by slow pyrolysis at a temperature of 550 °C in a muffle furnace, titled as WB and RB respectively. The yield of biochar was determined based on weight of biochar produced per unit weight of raw material. The amount of ash in the biochar was determined by heating five grams of biochar at 500 °C for more than 8 hours and weighing it again. The pH and electrical conductivity were measured in a mixture of biochar and deionized water with a weight ratio of 1: 20 (biochar: water). The total amount of carbon, hydrogen, and nitrogen in biochars was determined by dry combustion. Two types of produced biochars were milled with a particle size of 63-250 microns, at levels of 0.7 and 1.4% by weight. Three repetitions in the form of aqueous suspensions were added to the cylinders containing undisturbed soil. Three cylinders of soil without biochar were also considered as control treatment. Soil cylinders were placed in a greenhouse for six months at a temperature range of 20-25°C and underwent several cycles of drying and wetting. At the end of incubation period, soil samples were obtained from cylinders. Soil properties including pH, electrical conductivity, organic carbon, hydraulic conductivity and aggregate stability were also measured. Thin sections were also taken out of soils and state of soil structure and voids were studied. The effect of two factors, including biochar type and biochar application level were analyzed as factorial in a completely randomized design by SAS statistical software. The comparison of the means was done by Duncan's test at the probability level of five percent.

The WB compared to RB, had a higher yield, and less ash content, pH, electrical conductivity and H/C and O/C. More mineral ash in biochar is likely to provide more electrical conductivity in RB. Both biochar had an alkaline pH (more than 7). The biochar used in previous studies were usually alkaline, but biochar can be produced with any pH in the range of 4 to 12. The raw biomass has a H/C  molar ratio of about 1.5, but with the pyrolysis, this ratio decreases. WB had less H/C compared to RB. Therefore, it can be concluded that WB had more aromatic carbon and it can probably be a more effective tool for carbon sequestration in soil. Presence of a lot of pores in biochar, especially WB which were visible in SEM photos, are very effective on vital soil functions such as aeration and hydrology. The organic carbon content of SL and L soils were significantly higher at biochar treatments compared to control. The hydraulic conductivity of SL soil at both application levels of WB and RB was significantly lower than the control. However, both application levels of WB and 1.4% of RB led to significant increase and decreases of hydraulic conductivity of L soil, respectively. The mean comparison showed no difference between bulk density of treatments and application levels of biochar to control treatment of SL soil. However, Bulk density of biochar treated L soils were less than control. Biochar treatment also result in significant increase of: mean weight and geometric mean diameter and decrease of fractal dimension of aggregates in L Soil.

WB and RB biochars had no significant effects on indexes of soil aggregate stability and bulk density of SL soil, but they led to significant improvement of bulk density and aggregate stability of L Soil. Although, assessment of thin section showed partial improvement of soil structure of both SL and L soils. Therefore, more time than 6 months of incubation probably is needed to significant improve of aggregate stability of SL. Application of both biochars led to increase of organic carbon of both SL and L soils. Hydraulic conductivity was decreased in SL soil as result of both biochar application which can lead to the increase of water retention. Although the increase of hydraulic conductivity of  L soils due to WB can be considered as a suitable approach for the decrease of  the runoff, Generally, it can be concluded that due to the significant effect of feedstock type on biochar characteristics and different characteristics of soils, various types of biochar do not have a similar effect on a particular soil, therefore, a type of biochar cannot have the same effect on different types of soil.

Considering high potential of zero-valent iron nanoparticles (NZVI) for contaminants remediation in surface and groundwater, it is important to investigate factors affecting their stability in aquatic environments. In this study, the effects of surface coating and background solution characteristics including nanoparticle concentration, ionic strength, electrolyte type and dissolved organic matter content on the stability of NZVI in aqueous suspensions were investigated. A number of four two-way factorial experiments based on completely randomized design with three replications were conducted to explore the effects of surface coating and each of four background solution characteristics on the stability of NZVI suspension. Initially, bare NZVI (B-NZVI) and Carboxymethyl cellulose coated NZVI (CMC-NZVI) were synthesized and characterized. Thereafter NZVI suspensions were prepared in distilled water at different levels of selected characteristics. The hydrodynamic diameter and zeta potential were then measured in each of prepared suspension. Results indicated CMC-NZVI suspensions were more stable rather than B-NZVI in all tested solutions. Increase in nanoparticle concentration, ionic strength and cation valence of background solution, increased hydrodynamic diameter and decreased zeta potential of NZVI which lead to more aggregation of NZNI and less stability of suspension. On the contrary, increase in dissolved organic matter content resulted in more stability of NZNI suspension. Results also showed that there are significant interactions between nanoparticle type and solution characteristics; as B-NZVI is more sensitive to change in solution chemistry than CMC-NZVI.