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Background & Objective: Vermicomposting is a promising, cost-effective, and environmentally friendly technology in organic waste management. In this study, the production of vermicompost by Eisenia Foetida earthworm from agricultural residues and sheep manure has been discussed. Materials and methods: In this study, sheep manure, straw and grape leaves wastes were used in different proportions to produce vermicompost. Perforated plastic boxes were used to support the growth of earthworms. After adjusted different proportions of these residues, their humidity was controlled and a number of earthworms of Eisenia Foetida species were introduced to each box. The pH and EC parameters were measured every two weeks and C/N ratio three times during the experiment. The duration of experiment was 120 days. The ANOVA test was used to compare the averages and Tukey and Kruskal-Wallis post-tests were also used to identify the source of differences in the mentioned variables. Findings: The results showed that the pH increased during vermicomposting process and was acidic again at the end of the process. The highest C/N decrease ratio and the highest EC increase were observed in the 100% sheep manure bed (b1) and the lowest C/N decrease was observed in the 100% straw bed (b6). Conclusion: Using vermicomposting is effective in waste management. It is recommended to use sheep manure in combination with other wastes to produce high quality fertilizer as well as increase the rate of vermicomposting process.

Introduction: Salinization of soil has been reported as a problem in many parts of the world. Salinization could occur either as a result of natural processes e.g. high concentrations of salt in parent materials or groundwater and/or anthropogenic actions such as over-irrigation. The salinization probably affects the chemical and physical properties of soil, soil microbiological processes, plant growth, and soil fauna. Both quantity and quality of water, however, are the most important eco-factors needed for earthworm survival and development, and also biodegradation processes. Materials and Methods: In order to investigate the effect of irrigation water salinity on the survival and growth of earthworm Eisenia Fetida, an experiment was conducted in a completely randomized design with three replications under environmental conditions of the laboratory of Soil Sciences Department of Bu-Ali Sina University in Hamedan. The different types of water used in this study were: distilled water and saline water made with NaCl salt with electrical conductivity (EC) of 2, 4, 6, and 8 dS m-1. The experiment was carried out using completely randomized design in plastic containers of size 19 × 13 × 8 cm. Ten earthworms per container used in each exposure regime were introduced into the relevant test salinity by placing them on the surface and allowing them to burrow in. The test containers were covered with perforated lids to limit water loss due to evaporation and kept in 16 hours light, 8 hours dark at 25°C in a climate chamber for 42 days. Sampling was done at 3, 15, 21, 27, 33, 39, and 42 days after earthworms were introduced to the substrates to investigate mortality and weight changes of earthworms. The LC50 (concentration at which 50% of the earthworms are killed) and the EC50 (effect concentration at which a 50% reduction in a measured parameter) values for the salts expressed as conductivity (dS m-1) were calculated on day 27 and 42 by using the Probit Analysis. Results and Discussion: On day 3, no significant effect of salinity on percentages of survival was found. The survival rate of Eisenia fetida was significantly affected in the EC range used during 42 days (Table 2). The irrigation with distilled water (EC0) had the highest survival rate while the irrigation water with EC 8 dS m-1 had the lowest value. During the 39 days of exposure, no significant difference was found in survival rate of earthworms between EC 2, EC 4 and EC 6 dS m-1, but at the end of day 42, the salinity levels with EC 8 dS m-1 had a significant effect on percentage of earthworm survival in which 91.68% mortality occurred. The mean weight change of earthworms exposed to water with EC 2 dS m-1 was not significantly different (p < 0.01) from those exposed to the distilled water during 39 days, but there was a decrease in earthworm weight on day 42. The calculated LC50 for mortality after 27 and 42 days was 7.5 and 4.31 dS m-1, respectively, and EC50 for growth was 7.94 and 6.82 dS m-1, respectively. Conclusion: Our results showed that increased salinity had harmful effects on the growth and mortality of the earthworms (Eisenia fetida). Salinity can have detrimental effects on earthworms at concentrations considered safe for many plant species. We determined 42 day LC50 for mortality 4.31 dS m-1 (2521 mg lit-1). The EC50 for growth was 6.82 dS dS m-1 (3989 mg lit-1). The weight of earthworms was significantly affected by NaCl and dispersion analysis showed that NaCl concentration had a statistically significant influence on the weight of earthworms. The argument for using NaCl is that it is the predominant salt in most saline environments particularly in wastewaters. Since the salt type is dependent on the source of the contamination, it is, therefore, possible that other salts apart from NaCl could be the main compounds in saline toxicity in a specific area. The results of the current study suggest that the effects of salinity depend on the salt composition. Therefore, it would be important to assess the type of salt ions in soil in risk assessment, as this affects the extent of toxicity to soil organisms. [ABSTRACT FROM AUTHOR]

The activity of terrestrial organisms and their populations is an appropriate index for assessing the quality and health of the soil in forest ecosystems, which related to the fertility, and reproduction of the habitat. Current research studied the effect of four forest stands with different composition of Fagus/Carpinus/ Alnus/Diospyros (600 -700 m), Fagus/Carpinus/Alnus (1100 - 1200 m), Fagus/Carpinus (1600 -1700 m) and pure Fagus (2100 - 2200 m) located in Golband district of Noushahr, on litter and soil qualitative characters. In each of forest stands, eight organic and mineral samples (25×25 area to 30 cm soil depth) were taken and transferred to the laboratory. To investigate the difference and or non-difference the studied characteristics among different forest stands, one-way ANOVA and the Duncan multiple tests were employed. The litter (carbon and nitrogen contents) and soil (water content, pH, organic C, total N, earthworm density/biomass, nematode density and microbial activities) properties were measured. According to results, the maximum of soil earthworms (with higher ratio of epigeic) and nematodes recorded under Fagus mixed with Carpinus, Alnus and Diospyros. In addition, tree diversity in mixed stand of Fagus/Carpinus/Alnus/Diospyros improved microbial activities (i.e. basal respiration, substrate induced respiration, microbial biomass C and N, microbial and metabolic quotients and carbon availability index) compared to the other studied forest stands. PCA is indicating the outstanding effects of soil organic and mineral layers on the variation of soil biological properties. The result of this research shows the positive role of tree species diversity in improving qualitative and soil health.

This study aimed to recycle sawdust and blood powder using Eisenia foetida earthworm and investigate some biochemical changes of these waste materials during vermicomposting. Blood powder was mixed with sawdust in proportions of 0, 5 and 10% and the mixture was allowed to pass through earthworm guts for four months. At intervals of 1, 2, 3, 4, 6, 8, 12 and 16 weeks, the biological activity (i.e. basal respiration), pH, EC, total organic carbon, total nitrogen and C:N ratio were determined. The results showed that the period of time, the concentration of blood powder and the interaction between these two significantly affected all parameters. As the incubation time increases, the cumulative amount of mineralized carbon, the total nitrogen and EC increase in all vermicompost treatments whereas organic carbon, C:N ratio and pH decreased. Adding blood powder to sawdust bed resulted in an increase in carbon mineralization rate, EC and total nitrogen while pH, organic carbon and C: N ratio decreased. At the end of incubation time, the treatment of sawdust with 10 % blood powder resulted in the highest amount of released CO2 (142.1 µg C g-1), EC (3.7 dS m-1) and total nitrogen (2.24 %) and the lowest amount of pH (6.6), organic carbon (22.5 %) and C: N ratio (12.4). According to the results, the process of vermicomposting can be used as a safe method for the disposal of sawdust and blood powder

Background and purpose: Increasing entry of heavy metals into the environment and its effects on social structure of soil organisms disturbs the soil ecosystem. Study of molecular and cellular soil invertebrate responses as biomarkers of environmental health can provide useful information in relation to the effect of pollutants on them. Accordingly the aim of this research was to study the effects of cadmium and lead on Biomass, lipid peroxidation (LPo) and total antioxidant capacity (TAC), as cell physiology markers, in Eisenia fetida earthworm. Materials and methods: In this study, acute toxicity test was carried out according to the Organization for Economic Co-Operation and Development (OECD) guidelines (NO 207). TAC and LPo levels were assayed by ferric reducing antioxidant power and thiobarbituric acid methods, respectively. Results: LC50 as a viability marker, for Cd and Pb (µg/cm2) were 54.84 and 14.18 in 24h, and 34.1 and 8.4 in 48h, respectively. By increase in concentrations of lead and cadmium the rate of mortality, weight loss, LPo and TAC increased. E. fetida was found to be more sensitive to Cd than Pb (P

Introduction: Land application of organic wastes and biosolids such as municipal sewage sludge has been an important and attractive practice for improving different properties of agricultural soils with low organic matter content in semi-arid regions, due to an increase of soil organic matter level and fertility. However, application of this organic waste may directly or indirectly affect soil bio-indicators such as microbial and enzymatic activities through a change in the activity of other soil organisms such as earthworms. Earthworms are the most important soil saprophagous fauna and much of the faunal biomass is attributed to the presence of these organisms in the soil. Therefore, it is crucial to evaluate the effect of earthworm activity on soil microbial and biochemical attributes, in particularly when soils are amended with urban sewage sludge. The purpose of this study was to evaluate the earthworm effects on biochemical and microbiological properties of a calcareous soil amended with municipal sewage sludge using Factor Analysis (FA). Materials and Methods: In the present study, the experimental treatments were sewage sludge (without and with 1.5% sewage sludge) as the first factor and earthworm (no earthworm, Eiseniafoetida from epigeic group, Allolobophracaliginosa from endogeic group and a mixture of the two species) as the second factor. The study was setup as 2×4 full factorial experiment arranged in a completely randomized design with three replications for each treatment under greenhouse conditions over 90 days. A calcareous soil from the 0-30 cm layer with clay loam texture was obtained from a farmland field under fallow without cultivation history for ten years. The soil was air-dried and passed through a 2-mm sieve for the experiment. Sewage sludge as the soil organic amendment was collected from Wastewater Treatment Plant in Shahrekord. Sewage sludge was air-dried and grounded to pass through a 1-mm sieve for a uniform mixture with soil matrix.Heavy metals concentrations were found to be below the maximum permissible limits for municipal sewage sludge. After applying sewage sludge treatments, the pots were irrigated (70% soil field capacity) for three months to achieve a relative equilibrium condition in the soil. Eight adult earthworms with fully-developed clitellum were added to each pot. In the pots with both earthworm species, 4 specimen of each earthworm species was added. At the end of the experiment (90 days), soil samples were collected from treatments and were separately air-dried for chemical analysis or kept fresh and stored (4oC) for microbial analysis. Finally, data obtained from the study were analyzed using multivariate analysis. Results and Discussion: Factor analysis led to the selection of three factors with eigen value greater than 1. The first, second and third factors were accounted for 62, 17.7 and 9.2% of the variability in soil data, respectively. The three factors together explained 89% of the original variability (i.e., variance) in the soil dataset. Consequently, three factors were retained to represent the original variability of the dataset. The first factor had 16 highly weighted variables with a negative loading for soil pH and positive loadings for other variables. The first factor, which included most soil indicators as input variables, clearly separated sewage sludge treatments. Most of the soil microbial characteristics were increased by sewage sludge application due to the high contents of organic matter and nutrients in sewage sludge, as well as low concentrations of heavy metals. Fungal respiration, bacterial respiration and microbial biomass carbon loaded heavily on the second factor with a negative loading for fungal respiration and positive loadings for bacterial respiration and microbial biomass carbon. The second factor, which included microbial biomass and community composition, noticeably discriminated earthworm treatments. In sewage sludge treatments, the dependence of E. foetidaspecies on soil microorganisms as a food source declined, because of the consumption of organic waste by this epigeic species. However, the activity and impact of A. caliginosa species from endogeic group was only related to soil microbial biomass probably due to selective feeding of soil microorganisms. Conclusion: Factor analysis was used successfully in discriminating the effects of sewage sludge and earthworm either alone or in combination on soil microbial and biochemical parameters. A. caliginosa species in soils amended with sewage sludge had a positive effect on microbial community and biomass, while E. foetidaspecies had no such effect. A. caliginosa species indirectly benefited from sewage sludge application following the increase of soil microbial biomass. In summary, A. caliginosa species positively affected microbiological and biochemical properties in soils amended with sewage sludge due to its less dependence on this organic resource.

Earthworm biomass is one of the most important quantitative indices of forests soil. Estimating the earthworm biomass in forest soils is often difficult due to changes in soil properties. This study aims at comparing the performance of multiple linear regression and regression tree models in estimating the earthworm biomass in different forest conditions. Earthworm biomass was sampled in 40 forest gaps and adjacent virgin forest. They were then separated from soil using hand-sorting method and weighted in 0.01 gr precision in compartment 32 Shastkolate forest. Physical and chemical soil properties were analyzed by using standard laboratory methods. The best fitted models were specified in multiple linear regression and regression tree models for estimating the earthworm biomass. The fitted models were then validated by using Mean Error (ME), Root Mean Square Error (RMSE) and Relative Error (RE) measures. Soil bulk density and total nitrogen explained 24% of total earthworm biomass variances in virgin forest while canopy area solely explained 66% of total variances in canopy gap. Multiple linear regression models overestimated the earthworm biomass while regression tree model underestimated the biomass in virgin forest but it was precise estimator in canopy gap. According to the results and due to heterogeneity in forest environment, it is recommended the research is done hierarchically for finding the important and effective variables (gap area and soil potassium in the current study) and after the site stratification based on these variables, the relationship between independent and dependent variables is studied.

Introduction: Earthworms are among the most important organisms in soil and their activities can be an indicator of soil quality. These organisms may be influenced by organic wastes application such as sewage sludge and subsequently affect soil quality. One of the quick and easy methods for soil quality monitoring is the use of biological indicators such as microbial activity. It is due to their quick response to changes in the environment. The purpose of this study was to evaluate the effect of earthworms on nitrification rate and arginine ammonification as microbial activity in a calcareous soil amended with urban sewage sludge. Materials and Methods: The studied soil was sampled from Shahrekord University land and sewage sludge belonged to the refinery sludge ponds of shahrekord. Based on dry weight, this organic waste had carbon and nitrogen, approximately 67 and 110 times more than tested soil, respectively. The organic waste in terms of quality and heavy metal concentrations was in class A. Experimental treatments were sewage sludge (without and with 1.5% sewage sludge) and earthworm (no earthworm, Eiseniafoetida from epigeic group, Allolobophracaliginosa from endogeic group and a mixture of the two species) as 2×4 full factorial experiment arranged in a completely randomized design with three replications. After applying sewage sludge, the pots were irrigated three months to achieve a balance in the soil. An adult earthworm per kg of soil was added and in the mixed treatments comparison species were 1:1. To prevent the exit of earthworms, the pots was closed with a thin lace. At the end of the experiment, soil was completely mixed. Part of it was stored in the refrigerator to measure the microbiological parameters. Chemical properties were measured by the air-dried soil. The effectiveness of a factor in the observed changes is shown by partial effect size (Tabachnick and Fidell 2012). So, partial effect size (Eta2p) for each source of variation (SS, earthworm and SS×earthworm) was calculated. Results Discussion: According to Eta2p, the role of sewage sludge application to increase total nitrogen was almost twice the earthworm and had a greater effect on the property. Because of low concentrations of heavy metals and high nutrient in sewage sludge, it increased nitrification rate and arginine ammonification by 16.7 and 62.5 percent, respectively. Considering that the indices represent microbial biomass activity, so we can say sewage sludge application increased theri activities. Sewage sludge application increased total nitrogen, because provided the substrate for heterotrophic bacteria. Consequently, ammonium production improved and stimulated activity of Nitrosomonas and Nitrobacter. There was a positive and significant correlation between total nitrogen, arginine ammonification and nitrification rate, that confirmed the occurrence of this process. Earthworm inoculation affected these two indicators (p

A 12-week feeding trial was carried out to assess the effect of fish meal replacement by earthworm meal (Eiseniafoetida) on growth performance, feed efficiency and carcass composition of Siberian sturgeon (Acipenserbaerii). Fish with mean weight 21.32 ± 1.91 (mean ± SD) were fed with five experimental diets which 0% (Control), 10% (EWM10), 20% (EWM20), 30% (EWM30) and 40% (EWM40) of fish meal protein was replaced by earthworm meal protein. At the end of the feeding trial final body weight, weight gain, condition factor, feed coefficient ratio (FCR) and specific growth rate (SGR) were monitored. Fish fed EWM10 and EWM20 had highest weight gain and final weight respectively but no significant differences were observed between different treatments (P>0.05). Fish fed EWM40 had lowest final weight and weight gain and significant differences were observed between this treatment and EWM10 and EWM20 (P0.05). Fish fed EWM30 showed lowest carcass lipid content that was significantly lower than control treatment (P< 0.05). This treatment also had highest moisture content and was significantly higher than control treatment (P

Soil macrofauna biodiversity has an important role in ecosystem services. In order to find how soil macrofauna biodiversity is related to trees and shrubs in riparian forest of Maroon River in Khuzestan province, soil macrofauna were collected using hand-sorting procedure from 0-10 and 10-25 cm soil depths in 50 cm × 50 cm plots, 50 meters from each other on transects 100 meters apart and perpendicular to the river. Totally, 175 sampling plots were taken. In each plot, quantitative characteristics of trees and shrubs were measured. Soil macrofauna abundance and biomass were highest at 0-10 cm soil depth. Macrofauna biodiversity had a stronger correlation with Tamarisk properties than Euphrates poplar. In contrast, macrofauna biodiversity was not different under Tamarisk and Euphrates poplar. But earthworm was higher under Euphrates poplar cover. The most important parameter of soil macrofauna biodiversity in this area was crown cover. Therefore we could state that regardless of tree species, crown cover of these forests should be conserved because it maintains soil macrofauna biodiversity.

This experiment was carried out to evaluate the effect of earthworm (Eisenia fetida) in diet for rainbow trout in a complete randomized design with 5 treatments in triplicates using 15 cages in a pound for 8 weeks. Ten fish with average weight 120 g was stocked in each replication.The earthworm (as fed) at the levels of 0, 25, 50, 75 and 100% was replaced with fish meal in rainbow trout diet. Results showed that feed intake decreased significantly (P < 0.05) as earthworm increased. The diets contain 25% and 50% earthworm showed no significane differences compared to control for weight gain, specific growth rate and feed conversion ratio (P > b0.05). The chemical composition analysis of fish meat showed that there were no significant effects between control and 25% and 50% earthworm in diet for dry matter, crude protein and ash, but fat content significantly decreaed as earthworm increased (P < 0.05). This present study showed that the earthworm (Eisenia fetida) can be used in rainbow trout diet up to 50% instead of fish meal.

Regarding the importance of Zagros forest ecosystems and the recent wildfires, interaction between fire severity and soil properties and macrofauna was investigated in this study. For this purpose three burning severity levels including: low (occurred at forest floor or outside oak sprout clumps), moderate and high severity (occurred inside the oak sprout clumps) were considered and compared respectively to control plots inside and outside the oak sprout clumps. Fifteen 0.5 × 0.5× 0.2 m. sample plots were randomly selected for each above-mentioned treatment along transects in the both burned and control blocks. Sampling was performed for two times, including 13 months (autumn) and 20 months (spring) after fire. Soil macrofauna were hand sorted and classified after their determination. Results indicated that low burning level changed neither the soil properties nor the macrofauna total number, whereas high burning level changed significantly both the macrofauna total number and the soil properties. Presence of earthworm and silverfish was positively correlated to litter thickness, soil organic carbon, nitrogen and moisture, based on canonical correspondence analysis (CCA), whereas elimination of earthworm and silverfish was positively correlated to decrease of the soil and litter properties at moderate and high burning levels.

Background and purpose: Increasing entry of heavy metals into the environment and its effects on social structure of soil organisms disturbs the soil ecosystem. Study of molecular and cellular soil invertebrate responses as biomarkers of environmental health can provide useful information in relation to the effect of pollutants on them. Accordingly the aim of this research was to study the effects of cadmium and lead on Biomass, lipid peroxidation (LPo) and total antioxidant capacity (TAC), as cell physiology markers, in Eisenia fetida earthworm. Materials and methods: In this study, acute toxicity test was carried out according to the Organization for Economic Co-Operation and Development (OECD) guidelines (NO 207). TAC and LPo levels were assayed by ferric reducing antioxidant power and thiobarbituric acid methods, respectively. Results: LC50 as a viability marker, for Cd and Pb (µg/cm2 ) were 54.84 and 14.18 in 24h, and 34.1 and 8.4 in 48h, respectively. By increase in concentrations of lead and cadmium the rate of mortality, weight loss, LPo and TAC increased. E. fetida was found to be more sensitive to Cd than Pb (P<0.05). Conclusion: According to the results, in presence of lead and cadmium LPo and TAC increase significantly in E. fetida earthworm. Therefore, measurement of MDA and TAC as cell physiology markers could be used to evaluate the sensitivity of E. fetida earthworm to Cd and Pb in management of pollution resources and environmental health. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVE: Increasing of world population and excessively consumption of the needed materials result to greatly household solid wastes generation that can threaten human health and environment. Thus, application of appropriate methods for solid waste disposal is effective on community health. This study was performed to identify the capability of native earthworms of Mazandaran province (Iran) for compost production from household solid wastes.METHODS: In this cross sectional study, the types of earthworms were separated based on appearance characteristics. Plastic bin, loam soil, sand and animal fertilizer were used for bedding. 50gr of vegetable (lettuce) was poured on the bed. Earthworms with a certain number and weight were located on soil bed. Sequential water was added to beds for moisture control. Seventeen and thirty-five days after loading, the soil of different beds were assessed for chemical and microbiological analysis. FINDINGS: The organic matter, organic carbon, nitrogen, phosphorous and electrical conductivity in initial substrate and vermicompost increased from 16.8% to 40.2 and 45.2%, from 1.95% to 3.9 and 5.85%, from 1.1% to 3.6 and 3.9%, from 1.8% to 2 and 2.6% and from 344 to 372 and 1068 microsiemens per centimeter, respectively. Ash percentage, C/N ratio and total coliforms in initial substrate and vermicompost decreased from 83.2% to 65% and 59.8%, from 1.75% to 1.63% and 1.49 %and from 4.5×106 to 3.3×103 and 1.3×103 MPN/100ml, respectively. CONCLUSION: The results of this study showed that earthworms can produce compost from household solid wastes during 17 days.

Populus euphratica Oliv. forests in river floodplains of Khuzestan province are degraded heavily. Tree plantation is one of the methods for restoration of these degraded sites. The plantations of Eucalyptus camaldulensis, Acacia salicina and Dalbergia sissoo were established in randomized complete block design in 1993 with three replications along Dez river. Soil macrofauna were collected by hand sorting, using two randomly located 0.25m2 sampling frames at each plot. All macroinvertebrate organisms (macroscopic organisms) in litter and mineral soil up to 25cm, were collected. Totally, 18 samples were collected. In these treatments, earthworm constituted the largest part of soil macrofauna. Earthworm abundance and biomass were highest in Acacia plantation whereas Arthropods did not show any significant differences. Since soil macrofauna was dominated with earthworm, its variations are in line with earthworm. The abundance and biomass of earthworm and soil macrofauna were negatively correlated with the C/N ratio. Lower earthworm abundance and biomass under Eucalyptus plantation could be as a result of its leaf phenolics or soil nitrogen limitation. Totally, it could be concluded that different tree species had various effects on soil macrofauna (especially earthworm) abundance and biomass. As Acacia species increased the soil macrofauna and improved soil fertility, it could be preferred species for plantation in this area.