kamran parvanak

In recent years, some farmers in the plains of Saman in the province of Chaharmahal and Bakhtiari have changed the use of almond orchards in this area to agricultural land and pastures in order to provide food and fodder. Since these activities are mostly carried out without sufficient knowledge of the soil environment, there can be a serious threat to reduce soil quality. Therefore, studies on the effect of different managements on different soil characteristics and in the direction of a sustainable soil resource are very important. In this research, the effect of land use change in these areas on some physical and chemical indicators of soil quality was investigated.

In order to investigate the effect of land use change on some physical and chemical indicators of the soil quality of three land use systems comprising a permanent almond orchard, permanent pasture and almond orchard converted to land were selected in the plain of Saman. 15 samples of soil (45 samples in total) were taken from 0 to 30 cm in the form of networks (30 x 30 meters) in each of the three land use systems considered. Some physical and chemical parameters of studied soil samples measured by standard methods.After collecting and saving data in Excel, a one-side analysis of variance (ANOVA) was performed on using the SPSS18 software and the comparison of the means was also carried out on the basis of the LSD test at a probability level of 1%.

The results of analysis of variance data showed that changing land use (changing of almond orchards to agricultural land) had significant effect on the indeces examined physical and chemical of at 0.01 level. The Land use change did not change the surface soil texture of the study areas. The soil texture of all three-study system was almost the same (clay loam inclined to sandy clay loam). According to the findings of the mean comparison, when almond orchards were converted to agricultural land, there was a significant reduction in total porosity, mean weighted diameter of soil aggregates (MWD), base infiltration rate, and soil organic carbon by 12%, 56%, 50%, and 54%, respectively. Conversely, there was a notable increase of 10%, 5%, 44%, and 18% in bulk density, pH, electrical conductivity, and soil lime percentage at a significance level of 0.01 (pr<0.01).In this study, substituting improved pasture plants with land grazed pasture significantly augmented the average of soil organic carbon, total porosity, solidity of soil aggregates (MWD) and base infiltration rate by 48%, 14%, 69%, and 40%, respectively, as compared to agricultural land at a significance level of 0.01 (pr<0.01). However, no significant difference was observed at a significance level of 0.01 (pr>0.01) between almond orchard and pasture land concerning the evaluated indicators.

Overall, the parameters analyzed indicate that organic carbon, mean weighted diameter of soil aggregates (MWD), and bulk density are reliable indicators of soil quality in the study area. The average values of these indicators provide an optimal alternative for management and tillage practices in various land uses. Moreover, due to the delicate and vulnerable ecosystems of Saman Plain, it is recommended to avoid converting garden lands (such as almond orchards) into agricultural lands within the study area. This approach will help prevent soil erosion in one of the most sensitive areas of the country.

Petroleum sludge is the waste of crude oil refining processes, and are the most priority organic pollutants found in the environment. The present study was carried out to evaluate the growth and phytoremediation ability of ornamental tall fescue (Festuca arundinacea Schreb.) and sunflower (Helianthus annuus L.) plant to petroleum sludge produced by Isfahan Refinery in contaminated soils in a greenhouse experiment. For this purpose, the air-dried petroleum sludge sample was added to an uncontaminated soil at ratios of 0 (control), 10 and 20% (w/w) and mixed thoroughly. Plastic pots were filled with called mixture (3 kg). The experiment layout consisted of split-plots arranged in a completely randomized design with three replicates. The results showed that with increasing sludge level from 0 to 10 and 20 %, the tall fescue germination decreased significantly (P<0.01). In sunflower plant this decrease was not significant. The mean values of plant heights and root and shoot dry weights for tall fescue only in 20% level of petroleum sludge showed a significant reduction when compared with control. However, in sunflower plant, this reduction was not significant in all three petroleum sludge levels (P<0.01). The highest reduction of total petroleum hydrocarbons (89%) in tall fescue rhizosphere was observed in petroleum sludge level of 10%. By increasing the petroleum sludge up than 10%, total petroleum hydrocarbons in rhizosphere of two plants significantly decreased (P<0.01). Because, tall fescue plant produces more roots than shoots and have more fibrous root systems that caused more reduct TPH, application this plant recommend as a appropriate species for phytoremediation of contaminated soils to petroleum sludge of Isfahan Refinery.

IntroudationSalvia sahendica is a perennial native odorant plant of Iran with a right stem, crustal and about 90-40 cm height. Due to the importance of the use of Salvia sahendica in various pharmaceutical, food and sanitary industries, and because of its potential for cultivation in stressful climates, this plant has attentions to cultivate in low-yielding lands. Until now, there is not a comprehensive study on the response of Salvia sahendica to drought stress. Therefore, in order to evaluate the possibility of production and development of its cultivation under drought stress conditions, this research was carried to investigate the effects of drought stress on some physiological parameters, percentage and yield of essential oil of Salvia sahendica and determining the tolerance threshold of this plant to stress in 1395 in field conditions. Material and MethodsThis experiment was conducted at the research farm of Mobarakeh steel complex which located at 40th kilometers of southwest of Isfahan, at latitude of 32˚ 21′ northern and longitude of 51˚ 27′ eastern. After field preparation, the plants were cultivated in plots with size of 1.5 × 1.5m by 50 × 50 cm spacing in a randomized complete block design with three replicates and 9 plants per replicate. At the beginning of planting, all plots were irrigated three times a week for two weeks until the plants were established. Then, the effect of various irrigation intervals including 4 (as control, which is traditionally the optimum irrigation rate of plant in studied area), 8, 12 and 16 days intervals were applied. At the end of the summer, a sample was taken from the cultivated plant. The plants were fractioned to roots and shoots and some physiological and biochemical indices including, relative water content of leaves (RWC), water potential of leaves, total chlorophyll and chlorophyll a and b, proline and soluble sugars contents, electrolyte leakage, the essential oil percentage and yield were determined. Statistical analysis was performed on the data using MSTAT-C software at 5% level and the correlation between traits was determined by SPSS software. Results The results of analysis of variance showed that the effects of different levels of irrigation intervals on water potential of leaves, relative water content of leaves, soluble sugars, electrolyte leakage, percentage and essential oil yield were discriminated at 1% statistical level while on proline and total chlorophyll, chlorophyll a and b contents at 5%. Based on the results of the comparison of the mean, by increasing irrigation interval from 4 to 8 and 12 days, the differences in the means of all investigated parameters were not significant and only in 16 days irrigation interval the noted parameters differed significantly(pr<0.05). The highest amount of RWC (95%), chlorophyll a, b and total chlorophyll were 2.47, 1.32, and 0.98 mg.g-1 respectively in control treatment. The highest water potential of leaves (-1.78 MPa), proline accumulation (3.1 mg.g-1) and electrolyte leakage (57.7%) were observed in16- day irrigation interval. Maximum amount of soluble sugar, percentage and essential oil yield by the mean of 2.55 mg.g-1, 0.3% and 14.3 kg.ha-1 respectively were obtained in the 12-day irrigation interval. The correlation of traits showed a negative relationship between chlorophyll a, chlorophyll b with proline, soluble sugars, percentage and essential oil yield. Conclusion By considering that non-significant differences were observed in stress resistance indices of this plant up to 12-days interval in comparison with control, it can be concluded with 95% confidence that an optimal irrigation interval for using of this plant in areas arid and semi-arid regions is 12 days irrigation interval, which saves irrigation water. Also, the results of this study showed that Salvia sahendica resisted to water stress by increasing accumulation of proline and soluble sugars (osmotic regulation). Therefore, the accumulation of proline and soluble sugars can be considered as a sensitive indicator for determining the degree of leaf turgidity. Also, in order to produce the highest amount of essential oil from Salvia sahendica, the mild stress (12-day irrigation) can be used.

Microbial contamination is one of the main concerns about the use of treated wastewater in irrigation. Therefore, the present study conducted to investigate the effect of treated wastewater on microbial contamination of urban landscape soils in Zahedan.

In this study, a 1600 m2 plot of palm trees in Zahedan were irrigated with treated wastewater and one plot were irrigated with well water (control treatment) were selected. From the soil of two plot, a random sample of 16 samples from 0 to 50 cm depth were collected in 1397. Sampling were done from treated wastewater and well water. Physical, chemical and microbiological properties of treated wastewater and well water and microbial parameters of soil samples were measured according to standard methods. Data were analyzed using a randomized complete block design with MSTAT-C softwares.

Based on the results of analysis of variance, the application of treated wastewater has a significant effect on the microbial parameters of irrigated soils in a 1% statistical level. The results of comparison of meanings by LSD showed, the application treated wastewater at compared to well water significantly (p<0.05) were increased total coliforms, fecal coliforms and egg parasites of soils to 93.3%, 86.8% and 80% respectively. Also, the soil microbial parameters of palm trees were higher than that of the control treatment and the standard limit for agricultural land.

The chemical quality of Treated Wastewater of the Zahedan was consistent with the standards of the Iranian environmental organization in terms of its application in agriculture. However, number of the total coliforms, fecal coliforms and egg parasites of treated Wastewater, as well as in the surface soil of palm trees were irrigated with this wastewater was relatively high that could be accepted for limited irrigation according to the Global Health Guidelines.

The grass is one of the plants that is used widely in the landscape of industrial centers. This plant has a high water requirement. So, because of low precipitations in recent years, from some medicinal plants are applied in landscape. Because, these plants not only resist to adverse environmental conditions, but also have low water requirement, nutrition and low maintenance cost in comparison to grass. However, in each region their adaptation and yield depends on various factors such as climatic conditions, physical and chemical conditions of the soil, water quality, irrigation intervals and type of plant. For this reason, the present study was designed to evaluate the compatibility of Salvia sahendica plant to water stress and determining the appropriate irrigation regime to apply as landscapes in industrial centers.

This experiment was conducted at the research farm of Isfahan Mobarakeh Steel Company. After field preparation, the research treatments including five irrigation interval (2 (control), 4, 8, 12 and 16 days) as the main factor and two plant including grass and Salvia sahendica as subsidary factors was carried out in a Split plot design with randomized complete block design with 2 × 2 meters plotted in 3 replications in 1395. After the establishment of plants, the water stress was applied by irrigation intervals. At the end of the summer, the plants (leaf, root and whole plant) were harvested and plant growth factors were measured in three replications. The means comparison conducted by LSD method using MSTAT-C software.

The results of analysis of variance showed that the effects of irrigation interval, species and their interaction were statistically significant at 1% on all morphological and physiological traits. Based on the results of the means comparison, by increasing the irrigation interval from 2 to 4, 8 and 16 days, a significant reduction in the studied traits were observed in the grass (pr<0.05). while, the lowest percentage of viability (5%), surface coverage (5%), visual scoring (10%), leaf area index (4%), relative water content of leaves (9%) and chlorophyll index (3%) was observed in the 16-day interval as compared with control plant, but the reduction of these traits in the Salvia sahendica was not significant to 16 days (pr>0.05). In this plant, the lowest records of named traits were (60%), (67%), (66%), (80%), (68%) and (59%) respectively in 16 days interval. In the grass, proline content, electrolyte leakage, the ratio of root to shoot dry weight and the root highest length were significantly increased by increasing irrigation intervals to more than 2 days (pr <0.05). These traits increased 4.7, 4.2, 2.3 and 2.6 times respectively in the 16-days irrigation interval in this plant. In Salvia sahendica, this parameters was not afftected to 16-days interval. In 16-days interval, these traits increased by 1.2, 2, 1.7 and 1.9 times respectively.

By considering that non-significant decreases were observed (pr>0.05) in the studied parameters of Salvia sahendica up to 12-days interval in comparison with control, it can be concluded that an optimal irrigation regime of this plant in order to use in the landscape is irrigation interval of 12-days. It saves water resources in comparison with grass. According to results, the use of Salvia sahendica is recommended for use as landscape and alternative of grass in the studied area and in other similar areas at confidence level of 95%.

Upon the conducted samplings through 1997-2006 in different regions of Iran including:Fars, Isfahan, Tehran, Semnan, Guilan, Mazandaran, and Golestan provinces, 214 speciesof host plants belong to 127 genera, and 58 families for Iranian whiteflies (Homoptera:Aleyrodidae) were ldentified. The most number of whiteflie's host plants were determinedin the families Leguminosae (21 species), Malvaceae (18 species), Solanaceae (14 species),Compositae (13 species), Rosaceae (14 species), Rutaceae (8 species), Euphorbiaceae (8species), Oleaceae (8 species), and Brassicaceae (7 species), respectively. On the basis ofconducted studies in different seasons, and different regions of the sampled provinces,many host plants including: Eucalyptus camaldulensis (Myrtaceae), Myrtus communis(Myrtaceae), Vitex pseudo - negundo (Verbenaceae), Malva parviflora (Malvaceae),Ziziphus lotus (Rhamnaceae) and Ricinus communis (Euphorbiaceae) were determined asimportant shelters for hibernation and survival of aleyrodids, because of evergreen andhaving the abundant foliages through year. Therefore, identification of important whiteflie's host plants in winter and early of spring, and planning for reduction or elimination of them from around the fields, can be accounted as fundamental process in Integrated Pest Management (IPM) of aleyrodids.