Biosorption Potentials of Pleurotus tuber-regium (Fr.) Sing in Lead and Cadmium Polluted Soil

Background/Aim: The heavy metals, cadmium (Cd) and lead (Pb), are often implicated as environmental pollutants. Therefore, the biosorption potential of Pleurotus tuber-regium in lead and cadmium polluted soil was investigated by this work. Methods: Four kilograms of each humus soil sample was weighed into eight different black nursery cellophane bags and polluted with 0.5 g, 1.0 g and 2.0 g of lead and cadmium in triplicate. Pleurotus sclerotia were then planted in these polluted soil samples, and distilled water was added ad libitum. Results: The results showed that the growth performance was dose-related in lead-polluted soil. The Pleurotus tuber regium mushroom in the lead-polluted soil samples indicated a dose-dependent absorbed lead concentration in the results. Cadmium-polluted soil samples did not support the growth of the Pleurotus tuber regium mushroom at the various concentrations of cadmium used after day 30. Therefore, the findings suggest that the Pleurotus tuber regium mushroom and its sclerotia have intrinsic properties for the absorption of lead and cadmium. Conclusion: The findings suggest that the Pleurotus tuber regium mushroom and its sclerotia have intrinsic properties for the absorption of lead and cadmium.

Differential Variation in Non-structural Carbohydrates in Root Branch Orders of Fraxinus mandshurica Rupr. Seedlings Across Different Drought Intensities and Soil Substrates

Non-structural carbohydrates (NSCs) facilitate plant adaptation to drought stress, characterize tree growth and survival ability, and buffer against external disturbances. Previous studies have focused on the distribution and dynamics of NSCs among different plant organs under drought conditions. However, discussion about the NSC levels of fine roots in different root branch orders is limited, especially the relationship between fine root trait variation and NSC content. The objective of the study was to shed light on the synergistic variation in fine root traits and NSC content in different root branch orders under different drought and soil substrate conditions. The 2-year-old Fraxinus mandshurica Rupr. potted seedlings were planted in three different soil substrates (humus, loam, and sandy–loam soil) and subjected to four drought intensities (CK, mild drought, moderate drought, and severe drought) for 2 months. With increasing drought intensity, the biomass of fine roots decreased significantly. Under the same drought intensity, seedlings in sandy–loam soil had higher root biomass, and the coefficient of variation of 5th-order roots (37.4, 44.5, and 53% in humus, loam, and sandy–loam soil, respectively) was higher than that of lower-order roots. All branch order roots of seedlings in humus soil had the largest specific root length (SRL) and specific root surface area (SRA), in addition to the lowest diameter. With increasing drought intensity, the SRL and average diameter (AD) of all root branch orders increased and decreased, respectively. The fine roots in humus soil had a higher soluble sugar (SS) content and lower starch (ST) content compared to the loam and sandy–loam soil. Additionally, the SS and ST contents of fine roots showed decreasing and increasing tendencies with increasing drought intensities, respectively. SS and ST explained the highest degree of the total variation in fine root traits, which were 32 and 32.1%, respectively. With increasing root order, the explanation of the variation in root traits by ST decreased (only 6.8% for 5th-order roots). The observed response in terms of morphological traits of different fine root branch orders of F. mandshurica seedlings to resource fluctuations ensures the maintenance of a low cost-benefit ratio in the root system development.

Bacterial Diversity in Soil Surround Subterranean Termites-Damaged Wooden Buildings in Seonamsa Temple and Effect of the Termites on Bacterial Diversity in Humus Soil

In order to determine the changes in microbial community due to termites, soil microorganisms surrounding the termites were investigated. First, bacterial communities from soil with termites collected at Seonamsa temple, Suncheon city, Korea were compared by next-generation sequencing (NGS, Illumina Miseq). The bacterial composition of soil from Daeungjeon without termites and the soil from Josadang, Palsangjeon, and Samjeon with termites were compared. Next, the bacterial composition of these soils was also compared with that of humus soil cultured with termites. A total high-quality sequences of 71,942 and 72,429 reads were identified in Seonamsa temple’s soil and humus soil, respectively. The dominant phyla in the collected Seonamsa temple’s soil were Proteobacteria (27%), Firmicutes (24%) and Actinobacteria (21%), whereas those in the humus soil were Bacteriodetes (56%) and Proteobacteria (37%). Using a two-dimensional plot to explain the principal coordinate analysis of operational taxonomic unit compositions of the soil samples, it was confirmed that the samples were divided into soil with and without termites, and it was especially confirmed that the Proteobacteria phylum was increased in humus soil with termites than in humus soil without termites.

Enzymative Activity of Soils in the Activity Territory of the Dzhida Tungsten-Molybdenum Combine (Western Zabaikalie)

The enzymatic activity (catalase, cellulase) of soils and technogenic sand on the territory of the former Dzhida tungsten-molybdenum combine (Western Transbaikalia) was studied. The objects of the study were the surface 0-10 cm layers of alluvial dark humus soil (Fluvisols) as a background, man-made sand (waste after mining and processing of tungsten and molybdenum ores) and soils of recultivated contours № 1, 3, 4. At the same depth, linen cloths were laid to assess the activity of cellulase. Differences in the activity of soil enzymes of the background soil and soils on the studied contours were established, depending on the level of heavy metals content in them and the technologies used for reclamation.

SCREENING OF THE CONTENT OF SOME HEAVY METALS AT THE HUMUS SOIL HORIZON OF THE TRANSCARPATHIAN REGION

Based on the screening of some heavy metals (HMs) content in the humus soil horizon of the Transcarpathian region, the regularities of the distribution of HMs in the soils of different landscape zones have been established. It is shown that increasing of the terrain height, the content of HMs in soils decreases (except for Mn and Hg) and for the total HMs content the values of the Spearman correlation coefficient are: Cu – (-0.84); Zn – (-0.83); Mn 0.77; Mo – (-0.91); Co – (-0.82); Pb – (-0.83); Hg – absent; for the content of acid-soluble forms: Cu – absent; Zn – (-0.72); Mn 0.75; Mo – (-0.89); Co – (-0.86); Pb – (-0.77); Hg is absent. This pattern is associated with the tectonic and geological features of the different landscape zones. The calculation of the migration coefficient (the ratio of the content of acid-soluble forms to the gross content) has been shown that in mountainous regions this indicator has the highest value for Zn, Pb, and Cu. That means the potential danger of migration of these heavy me­tals and their bioavailability. This is probably connected to the type of soil in the mountai­nous areas of the region. A pronounced inter-element correlation of the HMs content in soils (except for Hg) has been established and the corresponding values of Pearson’s coefficients for the gross content are: Cu:Zn – 0,96; Cu:Mn – (-0,84); Cu:Mo – 0,89; Cu:Co – 0,99; Cu:Pb – 0,87; Zn:Mn – (-0,79); Zn:Mo – 0,91; Zn:Co – 0,96; Zn:Pb – 0,86; Mn:Mo – (-0,86); Mn:Co – (-0,84); Mn:Pb – (-0,75); Mo:Co – 0,87; Mo:Pb – 0,81; Co:Pb – 0,87. This makes it possible to predict the content of several HMs in the soils of the Transcarpathian region based on the results of determining one of them. In general, the content of HMs in the humus soil horizon (total content and content of mobile forms) is lower than the corresponding values of maximum permissible concentrations.

Investigating the environmental pollution caused by steel slag in Dana steel rolling mill plant, Katsina

Presence of heavy metals in the soil may contaminate the surrounding environment which causes chronic diseases. The waste steel slag in Dana steel rolling mill Katsina, Nigeria is always dumped within the premises of the company. Therefore, this research examined the level of environmental pollution caused by the deposited steel slag. Minipal 4 version of PW4030 X –Ray Fluorescence Spectrometer (XRF Spectrometer) was used to analyse the chemical composition of sample A (slag), sample B (mill scale), sample C (humus soil) and sample D (humus soil and slag) at Centre for Energy Research and Training, Ahmadu Bello University, Zaria, Kaduna State, Nigeria. Chemical compounds were detected in all the samples with oxides, Fe2O3 (11.8% - 86.13%) and SiO2 (4.41% - 57.7%) dominating. Product moment correlation coefficient was used to compare the effect of Slag (sample A) on Humus soil (sample C). The result obtained has shown that, the calculated value r = + 0.763 is greater than the table value r = + 0.483 at 5% level of significance and 15 d.f. This indicates that, the correlation between the two samples is highly significant. Fe2O3, MnO and ZnO trace elements in the humus soil were enriched after cultured with slag sample and P2O5, K2O, CaO, and SO3 trace elements that are useful for plants growth and development were leached.

Hibernation Period in Some Land Snail Species (Gastropoda: Helicidae): Epiphragmal Structure and Hypometabolic Behaviors

In this study, the hypometabolism behavior, epiphragm formation process, and the mineral composition of the epiphragmal structure of the Helix pomacella, Eobania vermiculata, Helix melanostoma, and Helix asemnis land snails were investigated during the hibernation period. 100 snails selected among mature individuals, 25 from each species, were collected from nature for the research. The snails were placed in four 50x50x5 cm pans containing 20-cm-deep humus soil. Snails were fed with lettuce by free feeding until the hibernation period. Hypometabolism behavior of snails that had hibernated between November and December 2018, and January and February 2019 were examined as entering the hibernation stage, hibernation stage, and leaving the hibernation stage. The ionic concentration (Calcium, Iron, and Phosphorus) of the epiphragm layer formed during the hibernation process was analyzed, its formation duration, and its degradation at the end of the hibernation period were examined. In the study, it was determined that the weight before hibernation reduced by 18-22% in all examined species (H. pomacella, E. vermiculata, H. melanostoma, and H. asemnis). The highest values in terms of epiphragm formation duration (19±0.30 days), weight (0.41±0.26 g), and thickness (0.310±0.22 mm) were determined in H. asemnis. In terms of the ionic concentration, the highest Calcium level was determined in H. asemnis (29.96±0.12 mg/g) while the highest Phosphorus level (4.02±0.20 mg/g) was determined in E. vermiculata, and the highest Iron content was found in H. pomacella (19.50±0.33 mg/g). The degradation duration of the epiphragm layer at the end of hibernation was determined the longest in E. vermiculata (7 days) whereas the shortest in H. pomacella (3 days). As a result of the present research, it was seen that the epiphragm layer is important for snails in terms of a sustainable life cycle and that the ecological tolerances of snails depend on the epiphragmal structure.

INCREASING SOIL FERTILITY

This article presents information about the importance of using composts prepared in different proportions nowadays to increase and maintain soil fertility. It is written about as a result of the usage and preparation of composts by mixing various organic wastes with phosphogypsum to improve and maintain soil fertility, a certain increase in humus in the soil, a decrease in soil capacity mass and an increase in porosity, the accumulation of nutrients in the soil provide an additional yield of 5-6 c / ha per hectare of cotton. KEYWORDS: soil, fertility, humus, soil properties, bulk density, porosity, compost, organic fertilizers, various wastes, cotton yield, yield.