Dumpsite Soil Research Articles

Soil degradation and Cu, Cr, Ni, Pb and Zn contamination in dumpsites of humid and semiarid tropical regions in northeastern Brazil.

We investigated soil characteristics and heavy metal content changes in 12 inactive dumpsites in humid and semiarid tropical climates in Northeast Brazil. The metals Cu, Cr, Ni, Pb and Zn in soil samples were determined by atomic absorption spectrophotometry. Other parameters measured include pH, electric conductivity, soil texture, soil organic carbon, total porosity and available P. The soil contents of sand, clay, soil organic carbon, available P and heavy metals, and soil bulk density, total porosity and pH were efficient indicators of soil degradation. We found no influence of current use, soil class or climate on the soil response. The mean concentrations of heavy metals in the dumpsite soils followed the order Zn (49.96mgkg-1) > Cu (38.48mgkg-1) > Pb (24.64mgkg-1) > Cr (21.94mgkg-1) > Ni (7.77mgkg-1). They were 6- to 36-fold higher than the background values for the region and were above the Brazilian guideline values for metals. The four dumpsite soils that showed simultaneous contamination with two or more heavy metals were located in the semiarid region. This challenges the assumption that soil impacts in the semiarid region are minimal due to lower leaching and high evaporation. Soil changes increase with time under activity, size and decommission time of the dumpsite. These data are important for local authorities to establish more effective targeting policies for closure of dumps and control of the spread of contaminants in areas impacted by the disposal of municipal waste.

Heavy Metals Concentration and Arthropod Population in Some Selected Dumpsites from Calabar, Cross River State, Nigeria

The aim of this research is to investigate the influence of refuse dumping on arthropods population and heavy metals concentration in Calabar Cross River state, Nigeria. Soil, and arthropod samples were collected from Lemna, Nassarawa, University of Calabar female hostel and Goldie market dumpsites which were labeled S1, S2, S3, and S4, respectively while same samples were picked from a plot of land labeled PC as a control. Arthropods were identified using light microscope and identification guide while heavy metals Cd, Pb, Cr, Ni, Co, As and Hg were analysed in soil and arthropods using Atomic absorption spectrophotometer (AAS). The results obtained showed 8363 arthropod individuals consisting of 19 species dominated by Muscidae (flies) family which constitutes about 20.39% whose presence indicates high level of pollution of the dumpsite and a possible health implication on people living around the dumpsites because these organisms are vectors for diseases such as yellow fever, malaria, Heavycholera and typhoid fever. Cadmium was the highest occurring heavy metal in dumpsites soil with a concentration of 1.457±0.493 mg/kg in S4 while As was the lowest with a concentration of 0.001 ± 0.000 mg/kg in S1 and Hg was below detection limit in all dumpsites. In arthropods, Cd had the highest occurrence with a concentration of 0.020 ± 0.001 mg/kg in S4 while Pb in S2 and Co in S1 with concentration of 0.001 ± 0.000 each were the lowest occurring metals. Heavy metals concentration in soil and arthropods from the dumpsites was higher than that of the control which shows the influences of refuse dumping and strong (> 5) positive correlation between mean metal concentrations in soil and arthropods suggests that these arthropods can be used as bio-indicators of heavy metals contamination and accumulation. It is therefore recommended that wastes be segregated and proper disposal methods should be adopted.

Orizontal transfer of haloalkane dehalogenase (LinB) gene among novel hexachlorocyclohexane (HCH) degrading sphingomonads isolated from contaminated soil

Soil samples from a HCH dump site and agricultural fields were collected from northern part of India in order to determine residue levels of a-, b-, g- and d- HCH and distribution of HCH degrading sphingomonads. The concentration of HCH residues was found to be very high in dump site soil (upto 4252.47µg/g) but it was low in the soil collected from the agricultural lands (upto 7.7µg/g). Eight novel HCH degrading strains could be isolated from HCH dump site soil but none from agricultural soil. Southern blot hybridization studies revealed the presence of haloalkane dehalogenase (LinB) genes alongwith IS6100 mobile genetic element in all of these strains. Further, 16S rDNA based phylogenetic analysis showed that these strains belong to the genus Sphingobium of family sphingomonadacae. An evidence for horizontal transfer of linB gene among these novel sphingomonads (only five were analysed) was derived by phylogenetic incongruency based approach. The sequence analysis of linB gene of novel isolates showed high sequence similarity (>98.9 to 100%) with each other indicating they were the homologs of same gene. Comparison of “species tree” with “linB gene tree” revealed incongruency among both the trees thus proving that this gene has disseminated among these novel sphingomonads in a recent HGT event. Presence of IS6100 element in all the strains further supported the evidence. This study reveals that the members of family sphingomonadacae are acquiring lin genes by horizontal transfer under high selective pressure of HCH and such phenomenon at a contaminated site is quite significant for bioremediation of HCH.

Concentration and Toxicological Risk Assessment of Heavy Metal Pollution in Dumpsite Soils within Benin City, Nigeria

Indiscriminate disposal of refuse and industrial effluents is a challenge in Nigeria. This poses a plethora of health and ecological risks from heavy metal contamination of soils. This study investigated the levels of heavy metal contamination in dumpsite soils and its effects on human health within Benin metropolis, Nigeria. The specific objectives were to determine the human and ecological risks via different exposure pathways. Soil samples were collected from three sampling stations, digested and analyzed for lead, cadmium, zinc, chromium, iron, nickel, manganese and copper using the Atomic Absorption Spectrophotometer (AAS). Pollution Indices and Human health risk were estimated using appropriate formulae. Results showed that that the mean concentrations of the investigated metals in the three stations were chromium (17.12±1.00, 17.65±1.05 and, 17.24±1.05 mg/kg), nickel (37.60±7.95, 40.98±1.46 and, 41.25±0.92 mg/kg), copper (48.57±4.91, 47.76±3.66 and, 48.05±3.46 mg/kg), lead (8.2±0.22, 8.17±0.52 and, 8.25±0.16 mg/kg), manganese (94.52±4.90, 94.98±6.69 and, 95.06±4.63), iron (467.98±36.69, 464.90±22.36 and, 462.15±10.64 mg/kg), cadmium (2.30±0.16, 2.22±0.11 and, 2.22±0.10 mg/kg) and zinc (142.93±3.93, 142.29±3.41 and, 142.87±3.86 mg/kg) respectively. Human health risk assessment revealed that the highest and lowest daily intake for the ingestion, inhalation and dermal pathway for both adults and children were Zinc and lead. Daily intake for children was higher than for adults via the three pathways with lifetime cancer risk (LCR) higher for children than adults. Carcinogenic and non-carcinogenic risk assessment shows that there were minimal risks from heavy metal contamination of the soils. Effective management and continuous monitoring of dumpsite soils is recommended to prevent negative impacts to man and the environment.

Ex situ studies on Macrotermes bellicosus as a potential bioremediation tool of polluted dump soil sites for Sub Saharan Africa

ABSTRACT Soil is a fragile ecosystem that could be contaminated by several factors such as anthropogenic and natural means: heavy metals, pesticides, hydrocarbon or petrochemicals, and leachates from wastes. This ex situ study intends to determine the bioremediation potentials of African mound termites (Macrotemes bellicosus) with their ability to improve the physical and to reduce the chemical and heavy metal contents in dumpsite soils. Three sites have been investigated (virgin soil, active dumpsite, dormant dumpsite). The influence of M. bellicosus on the dumpsite soil was appraised statistically using General Linear Model Analysis of Variance set at p > 0.05 is not significant. The activities of the termites reduced the heavy metals to Fe(III) (1.10 mg/kg), Mn(III) (1.37 mg/kg), Zn (15.30 mg/kg), Cu(II) (0.95 mg/kg), Cr(III) (0.19 mg/kg), Cd (2.25 mg/kg), Pb (0.10 mg/kg), Ni (0.08 mg/kg), V(V) (0.05 mg/kg), and THC (0.90 mg/kg) with F values of 2.07, 1.87, 1.51, 1.36, 1.47, 1.35, 1.85, 3.04, 3.00, and 1.42. The termites were able to significantly reduce the levels of the chemical loads of the dump soil at different day intervals (0, 30, 60, and 90 days) in the active site. Gentle variations were also noticed in dormant and virgin sites correspondingly. The level of heavy metal concentrations in Macrotemes bellicosus was in the following ranks: Fe(III)>Zn>Pb>Cr(III)>Cd>Mn(III)>Cu(II)>Ni>V(V). The bioaccumulation factors for heavy metals in the termites revealed that Fe(III) and Zn had values >1 and ≥1, correspondingly. The study established the potentials of insects like Macrotemes bellicosus for entomoremediation purposes. Prospective utilization of this novel biosystems and biotechnology will enhance the restoration and healthy ecological balance of any dumpsite soil or polluted environments in situ.

Production of α-amylase from Aspergillus flavus S2-OY using solid substrate fermentation of potato (Solanum tuberosum L.) peel

Amylases find commercial applications in diverse industries. This study investigated the production of α-amylase from a fungus, using potato peel as an alternative substrate. Six fungal isolates from the soil of cassava waste dumpsite were tentatively identified as two Aspergillus species and one species each of Rhizopus, Trichocladium, Neosartorya and Ascodermis. They were screened for their relative amylolytic activities using the starch agar hydrolysis test. Molecular characterization, using the ITS rRNA gene sequencing, was used to confirm the identity of the selected fungus as Aspergillus flavus S2-OY. Amylase production from the fungus via solid substrate fermentation of potato peel was carried out and the effect of production parameters investigated. Maximum α-amylase production was at an incubation period of 72 h, pH of 5.0 and temperature of 25 °C. Casein and maltose were the best nitrogen and carbon sources, respectively while the optima inoculum and moisture volumes for enzyme production were 1.5 mL and 5.0 mL, respectively. Aspergillus flavus S2-OY has great potential for α-amylase production using potato peel as an alternative and cheap substrate, under solid substrate fermentation condition. This has implications for the cost-effective production of an industrial enzyme and reduction of environmental pollution problems through effectual management of agro-industrial wastes.

Molecular Characterization of Fungi Associated with Dump Site Soil

Aims: A study was conducted to identify fungal species isolated from dumpsite soil in University of Port Harcourt using molecular techniques.
 Methodology: Molecular methods for determining the species of a fungus based on the amplification and sequencing of the internal subscribed spacer (ITS) region of the fungal rRNA operon using molecular markers was applied. Soil sample was collected from a dumpsite in the University of Port Harcourt, Rivers State, Nigeria. Isolation of fungi associated with the dumpsite soil was carried out using spread plate method. Fungal genomic DNA was extracted using Quick-DNA Fungal/Bacterial Miniprep kit. The ITS1-2 gene of the isolates was amplified by Polymerase Chain Reaction (PCR) using the primer pair; ITS4 and ITS5.
 Results: The sequences of the amplified ITS region were blasted against known sequences on the National Centre for Biotechnology Information (NCBI) database. Nucleotide sequence analysis revealed the species identity of the fungal isolates to be: Aspergillus fumigatus, Trichoderma harzianum, Aspergillus felis, Aspergillus templicola, Aspergillus flavipes, Aspergillus fumigatus and Cunninghamella binariae. Phylogenetic analysis was carried out to ascertain the relationship between the isolates and other closely-related isolates on GenBank. Isolates 2 (Trichoderma harzianum) and 7 (Cunninghamella binariae), 3 (Aspergillus felis) and 6 (Aspergillus fumigatus), and 4 (Aspergillus templicola) and 5 (Aspergillus flavipes) were found to be more closely related to each other.
 Conclusion: The molecular techniques employed successfully identified the organisms to the species level as these techniques are based on the genetic constitution of organisms. The result obtained from this study will complement the information on the fungal organisms associated with dumpsite soil.

Constituents of Leachate Generation and Migration in Ministry of Agriculture Forest Nursery Open Dumpsite in Jos Plateau State, Nigeria

The constituents of leachate generation and migration in ministry of agriculture nursery open dumpsite in Jos Plateau were determined. Leachate extraction from solid waste (SW) was carried out. Test dumpsite soil with different elevations. Elevations were with uniform density. Representative solid waste dumpsite soil sample were collected from one dumpsite. The collected SW soil subjected to column experimental test, results showed physicochemical parameters (pH, TSS,TDS and EC) range of descriptive value in terms of histogram values of 5.66 – 8.23(1.0m to 1.5m depth) pH, 90.65 – 1125.96mg/l (0.5 to 2.0m depth) TSS, 17.78 – 156mg/l (1.5 to 0.5m depth) TDS, 9.02 – 80.01 us/cm and principal component summary analysis. The histogram and principal component summary values increase. Alkalinity has highest concentration, followed by hardness which has least, BOD5 has lower values, followed by COD which has higher value, Cl−increasing, S04 2-, N03 values increases, P04 in waste decreases with increase time and depth. The Na+, increasing K+ second to Na+, increases, Mg2+ and Ca2+ in MSW increases as time and depth proceed. The results of Cu, Fe, Cd and Pb in histogram had moderate to high values. All were examined for physicochemical, alkalinity and hardness, BOD5, COD, anions, cations and heavy metals to study the seasonal variation of significant parameters. The results from the leachate analysis were used as a tool to identify the processes and mechanisms affecting the soil and water chemistry from the study area.

Pollution sources identification, health, and radiological risk assessment of naturally occurring radioisotopes and heavy metals in waste dumpsites in Ijebu-Ode, Ogun State, Southwest Nigeria

This study evaluates human health, pollution, and radiological risk assessment of potentially toxic metals (PTMs) (Pb, Cd, Cr, Ni, and Zn), radioisotopes (238U, 232Th, and 40K) and its associated radiological indices from dumpsite soils in Ogun State, Nigeria, using a calibrated atomic absorption spectrophotometer (AAS) and highly shielded γ-ray spectrometry using NaI(TI) detector. Fourier transform infrared spectrometer (FTIR) complemented by X-ray diffraction (XRD) techniques were used to evaluate the mineralogical composition of the soils. Multivariate statistical analysis was used to apportion the source of PTMs and the radioisotopes. The mean concentration of Pb, Cd, Cr, Ni, and Zn obtained were 22.35, 17.95, 20.83, 19.02, and 75.88 mg kg−1, respectively. The activity concentrations of 238U, 232Th, and 40K ranged from 49.71 ± 16.3 − 314.15 ± 55.2, BDL − 87.54 ± 7.38, and BDL − 3721.3 ± 231.6 Bqkg−1, respectively. The values obtained were above the global average value in most of the samples. According to the four-pollution and ecological risk assessment model, the dumpsite soils are strongly to low polluted and enriched with toxic metals in the order Zn > Cr > Pb > Ni > Cd. The estimated carcinogenic risk of the three carcinogenic PTMs for children and adults were higher than the acceptable limit (1 × 10−6). The results of the PCA and HCA results are consistent with the correlation coefficient analysis which showed that mixed natural, anthropogenic and lithogenic sources mainly from aggregation of lead-containing materials in the waste on the dumpsite, vehicular emission and industrial discharges are the main sources of Pb, Ni, and Cd in the three studied dumpsites. Thus, dumpsite soil poses great threat to health, increased pollution and enhances the radiological risk to the general population via human multiple exposure routes.

A thermostable extracellular α-amylase from Aspergillus flavus S2-OY: Purification, characterisation and application in raw starch hydrolysis

An amylolytic fungus was isolated locally from the soil of a cassava waste dumpsite. It was identified as Aspergillus flavus S2-OY using 18S rRNA gene sequencing with gene bank accession number MZ267053.1. α-Amylase was produced from the fungus through solid substrate fermentation of potato (Solanum tuberosum L.) peel, a cheap and renewable substrate. The fungal enzyme was purified 13.41-fold by ammonium sulphate and ion exchange chromatography (CM Sephadex C-50), with final yield of 13.41%. Apparent molecular weight of 55.0 kDa was obtained for the purified enzyme, using SDS-PAGE. Optima pH (6.0) and temperature (70 °C) of α-amylase activity were determined for the enzyme which also showed thermal stability up to 70 °C, with 80% residual activity after 120 min. The enzyme exhibited a wide range of pH stability (4.0 to 7.0). Kinetic parameters Km and Vmax values obtained with soluble starch were 158 µg/ml/min and 1.51 mg/ml, respectively. The enzyme was slightly inhibited by Mg2+. Mn2+, Zn2+, Na+, K+, Hg2+ and the chelating agent, EDTA, at 5.0 mM concentration. However, it was activated by Sn2+. The enzyme hydrolysed gelatinised and ungelatinized raw yam, corn, rice and millet starches strongly but cassava starch moderately. These results revealed that cost-effective α-amylase production from Aspergillus flavus S2-OY could be realised with the use of potato peel as a cheap substrate, under solid substrate fermentation condition. Also, the fungal α-amylase is a raw starch-hydrolysing, acid to neutral and thermostable enzyme with potential for broad biotechnological applications.

Environmental Implications of Municipal Dump Site on Soil Nitrogen in Calabar Metropolis, Nigeria

Organic matter exhibit strong variations in nitrogen retention and transformation cycle in soil. However, nitrogen could be altered by seasonal variations, leading us to hypothesize that the open municipal waste dump site in Calabar exposed to dry and wet season could alter nitrogen dynamics in that soil. A total of sixty (60) composite soil samples were collected at different landscape positions (summit crest, shoulder slope, toe slope, interfluve slope, valley floor) of a municipal dump site and a control (no refuse area) during the dry and wet seasons in Calabar and analyzed to ascertain the effects on forms and status of soil nitrogen. The soils were loamy sand across the study location with pH values of 4.50, 7.00, 6.70, 7.30, 5.00, 7.30 (dry season) and 5.00. 7.30, 7.00, 7.40, 5.90, 7.40 (wet season) for the control, summit crest, shoulder slope, toe slope, interfluve slope and valley floor accordingly. Values obtained for total nitrogen (N) from the study site were generally low (<0.21 %), with values for dry season slightly higher than the wet season. NH4+ recorded higher content in wet than in dry season with values ranging between 12.11-14.11 mg/kg (control), 14.60 - 15.90 mg/kg (Summit crest); 18.25 - 20.05 mg/kg (Shoulder slope), 18.30 - 20.20 mg/kg (Toe slope), 12.30 - 14.00 mg/kg (Interfluve slope) and 9.24 -11.07 mg/kg (Valley floor). The Shoulder and toe slopes recorded the highest NH4+ concentration in the wet season. N02- contents documented for the control site were within the ranges of 2.78- 3.20 and 3.22-3.62 mg/kg while the dumpsite had values between 2.49-3.45 and 2.98 -3.22 mg/kg was observed for the shoulder position, the toe slope contained between 2.30-2.75 and 2.70 -2.82 mg/kg, the inter fluve slope had similar ranges of 2.32-2.90 and 2.70-3.08 mg/kg, and the valley floor 2.45-2.60 and 2.78-2.98 mg/kg. N02- values were higher for the wet than dry season. NO3- nitrogen was observed to be excessive across the dumpsite with the highest values > 80 mg/kg obtained at the valley floor. The NO3- values were higher in dry season across the all the landscape positions than in the wet season. The values were equally higher for the dumpsite than the control. It was observed that the dumpsite soils contend excessive NO3- which could be converted to nitrous oxide (N2O) thus contributing to green house (GHG) emissions. It was also noted that seasonal variation did not significantly affect the N content at the different landscape positions of the municipal dumpsite in Calabar. It is highly recommended that municipal waste be sorted and the organic materials composted to harness the rich NO3- content as observed in this research.
 
 Received: 22 September 2021 / Accepted: 25 October 2021 / Published: 5 November 2021

ISOLATION, CHARACTERIZATION AND ANTIBACTERIAL SREENING OF ANTIBIOTICS PRODUCED FROM STREPTOMYCES ISOLATED FROM DUMPSITE SOILS IN ILORIN, NORTH CENTRAL NIGERIA

Antibiotics are one of the most exploited metabolites produced by soil actinomycetes. This study isolated fifteen actinomycetes (A1 – A15) from dumpsite soils within Ilorin metropolis & screened them for antibacterial activity. Isolates were identified with morphology & biochemical characteristics.Their activity against clinical bacteria (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae & Staphylococcus aureus) was determined. Their bioactive metabolites after fermentation was assayed for by agar well diffusion & compared with reference antibiotics. Molecular analysis of two most active isolates was done. The most active metabolite was subjected to GCMS. All isolates were identified as Streptomyces, 7 isolates exhibited activity against 3 test bacteria with highest (10.5mm±0.35) by Streptomyces griseoplanus while S. aureus demonstrated total resistance to all isolates. Secondary activity revealed 7 of the metabolites as effective against the bacteria with highest activity (28.5±1.04mm) by S. sparsogenes showing similar activity with Cefuroxime (28.01±0.01mm). The two most active isolates were Streptomyces griseoplanus strain NR725RL-ISP 5009 & Streptomyces sparsogenes strain NBRC 1308616S & RNA nucleotide similarity revealed close phylogenic relationship. GC-MS revealed10 compounds in S. sparsogenes strain NBRC 1308616S metabolite. Streptomyces from dumpsite soils within Ilorin produced bioactive compounds against clinical test bacteria and thus could be potential sources of antibiotics.

Photocatalytic degradation of low-density polythene using protein-coated titania nanoparticles and Lactobacillus plantarum

ABSTRACT The biodegradation of low-density Polyethylene (LDPE) is usually time-consuming, In the presence of Titania-nanoparticles, LDPE is photocatalytically degraded in smaller fragments afterward the bacteria can effectively degrade polyethylene. In the current study, potent polyethylene degrading bacteria were screened from the soil of the local dumpsite and identified using 16s rRNA sequencing. The protein-coated titania nanoparticle (TNPs) was synthesized using Sol-gel Method and characterized by XRD, and SAED-HRTEM. The photocatalytic biodegradation of LDPE (30 microns) in presence of 1M NaOH was studied by exposing it to UV irradiation, visible light, and high temperature (50°C) for 21 days separately and photocatalytic biodegradation was assessed by monitoring % weight loss at every 7 days’ time interval, tensile strength, and FTIR. After 21 days of photocatalytic biodegradation, LDPE film containing both TNPs and Lactobacillus plantarum along with 1M NaOH in presence of visible light was unveiled oxidation and enumerated via the occurrence of strong absorptions band of the carbonyl group (C=O) and also the breaking and weakening of existing absorptions bonds along with the new carbonyl functional group formation. The decline in tensile strength was measured at 21% after 21 days. Thus, experimental results on LDPE after exposure to visible irradiation along with Lactobacillus plantarum and 5% protein-coated TNP showed improvement in degradation rate and elongation 59 % and 51% within 21 days, respectively in comparison to another study (49 % Weight loss and 12% elongation after 45 days). An excellent application of this research is significantly reduced plastic waste via a maintained procedure.

Nitrogen addition facilitates phytoremediation of PAH-Cd cocontaminated dumpsite soil by altering alfalfa growth and rhizosphere communities

Thousands of unlined landfills and open dumpsites seriously threatened the safety of soil and groundwater due to leachate leakage with a mass of pollutants, particularly heavy metals, organic contaminants and ammonia. Phytoremediation is widely used in the treatment of cocontaminated soils because it is cost-effective and environmentally friendly. However, the extent to which phytoremediation efficiency and plant physiological responses are affected by the high nitrogen (N) content in such cocontaminated soil is still uncertain. Here, pot experiments were conducted to investigate the effects of N addition on the applicability of legume alfalfa remediation for polycyclic aromatic hydrocarbon‑cadmium (PAHCd) co-/contaminated soil and the corresponding microbial regulation mechanism. The results showed that the PAH dissipation rates and Cd removal rates in the high-contamination groups increased with the external N supply, among which the pyrene dissipation rates in the cocontaminated soil was elevated most significantly, from 78.10% to 87.25%. However, the phytoremediation efficiency weakened in low cocontaminated soil, possibly because the excessive N content had inhibitory effects on the rhizobium Ensifer and restrained alfalfa growth. Furthermore, the relative abundance of PAH-degrading bacteria in the rhizosphere dominated PAH dissipation. As reflected by principal coordinate analysis (PCoA) analysis and hierarchical dendrograms, the microbial community composition changed with N addition, and a more pronounced shift was found in the rhizosphere relative to the endosphere or shoots of alfalfa. This study will provide a theoretical basis for legume plant remediation of dumpsites as well as soil contaminated with multiple pollutants.

Impact of Wastes on Some Properties of Soil around an Active Dumpsite in Ibadan, Southwestern Nigeria

Recently most farmers in developing country like Nigeria has resulted to the use of solid wastes as compost to replenish the deteriorated soils while some are farming on the abandoned waste dumpsite due to their richness in organic matter. This study assessed the soil nutrient and fertility status by investigating the influence of wastes (if any) on physical and chemical properties of soils in and around Lapite dumpsite for environmental sustainability. Ten soil samples each collected from three locations: dumpsite, downslope and upslope sites at depth of 0-20cm were analyzed for soil texture, bulk density, porosity, electrical conductivity, pH, organic carbon, organic matter content (OMC), total nitrogen (TN), available phosphorus (AP), Na, K, Ca, Mg, Fe, Zn, Cu, Pb and Ni. Significant differences were observed on soil physical: moisture content (18.05-38.11 %); Bulk density (1.01-1.54 g/cm3); porosity (49.09-74.56 %) and chemical properties: : OMC (1.39-5.98 %);TN (0.58-1.60 %); AP(0.35-1.09 %) among others in soils from the studied location sites at p ≤ 0.05; however, no remarkable impact was noticed on soil texture. This study has shown that deposition of wastes has impacted the physical and chemical properties by improving soil organic matter contents and increasing nutrient contents such as exchangeable bases and micronutrient, thus enhancing soil organic matter, fertility and productivity status of the soil for maximum plant growth. However, increase in heavy metal concentrations in dumpsite soils call for incessant assessment and monitoring, thus sorting, reuse and recycling should be encouraged to reduce the metal loads over time.

Lipolytic Activities of Bacteria and Fungi Isolated from Soil Samples

This study was carried out at the Department of Microbiology, Microbiology Laboratory, Ado-Ekiti State University, Ekiti State, Nigeria between July, 2018 to March, 2019. Due to the diverse biotechnological importance of lipases as a biocatalytic enzyme, extracellular production of microbial lipases has to gain lots of interest. This study, therefore, focused on the physicochemical parameters of lipase producing microorganisms from different soil samples. Microorganisms were isolated from four different soil samples using Nutrient Agar (NA) and Potato Dextrose Agar (PDA). The isolates were identified and characterized. Production, an assay for Lipase enzymes, purification, the effect of pH, Temperature and metal ion was investigated. The isolates were culturally, morphologically and biochemically characterized. Two of the bacteria strains (Bacillus sp. and Staphylococcus sp.) and four fungi (Fusarium sp., Aspergillus fumigatus, Aspergillus niger, and Trichophyton sp.) isolates were able to produce lipid using Sudan Black B Fat staining techniques. Fusarium sp. isolated from dumpsite soil had the highest specific lipase activity (21.16 µmol/min/ml) while Bacillus sp. isolated from red oil spill soil had the highest lipase activity (0.59 µmol/min/mg). The specific activity of partially purified lipase for Fusarium sp. was 2.39 µmol/min/mg while Bacillus sp. had a specific activity of 2.46 µmol/min/mg. 30oC - 50oC, pH 7.0 to 9.0 and KCl2 (139.672%) supported the highest production of lipase by the Bacillus sp. and Fusarium sp. This study demonstrated that the Bacillus sp. produced a high amount of lipase activity followed by Fusarium sp. Extensive and persistent screening for new microorganisms and their lipolytic activities will help to provide faster ways to solve most environmental soil pollution.

Effect of dumpsite organic manure soil on growth, nutrient content, and yield of Curcuma longa L.(turmeric) in Owerri, Imo State

Curcuma longa L.(turmeric) is one of the most essential available spices in Nigeria. The field study was conducted at Teaching and Research Farm of Faculty of Agriculture and Veterinary Medicine, Imo State University, Owerri, Nigeria. During the planting season of 2019 to assess effect of different levels of Dumpsite Organic Manure Soil on Growth parameters, nutrient content and yield of turmeric. The experiment was laid in Randomized Block Complete Design with three replications. T­1: Control, T2: 05 tons; T3 10 tons, T4: 15 tons of Dumpsite Organic Manure Soil. The result of the study revealed that high doses (T­4­) of Dumpsite soil significantly influenced maximum growth parameters viz; plant height, leaf area, leaf length, leaf area index.15 tons of Dumpsite Organic Manure Soil (T4) recorded the maximum yield per hectare (17.66kg/h) while the lowest (6.863kg) was obtained from control. The result of proximate composition showed that 15 tons (T4) of dumpsite organic manure soil significantly improve the Ash, Fibre, Protein and carbohydrate contents compare to control. Moisture content (81%) and fat content (0.6369%) were higher in control compare to other treatment levels. The result has shown that Dumpsite Organic Manure Soil has potential to improve growth of Turmeric (Curcuma longa L.) and other crops.

Acetaminophen degradation using bacterial strains isolated from winogradsky column and phytotoxicity analysis of dump site soil

The increase in pollution increased the threat level of living organisms in the environment. Municipal Solid Waste is one of the most important wastes which contribute to polluted sites affecting livelihood. They pollute the water stream, marine environment ecology, soil fertility, and agriculture production. This, in turn, reduces the microflora of the marine environment, agricultural soil, and fertility. This could be analyzed by setting up a Winogradsky column using dumpsite soil samples. The current work was designed to study the municipal solid wastes from different dumpsite soil. Soil characterization revealed that the pH of Kodungaiyur and Otteri was 7.3 and 6.4. The bulk density was 0.067 g/cm3 and 0.069 g/cm3. The Porosity resulted to be 0.511 particle/volume and 0.513 particle/volume for Kodungaiyur and Otteri. The Kodungaiyur soil containing contaminants supplied with natural sources showed a 100% germination index, and Otteri soil containing contaminants supplied with natural sources showed a maximum vigour index. The presence of medicinal strips in the collected soil samples led to the study on Acetaminophen degradation. HB1 showed to be 79 ± 0.005% at optimum pH 5 containing 100 mg/L of Acetaminophen at day four among the isolated bacterial strains. Further, the intermediate formation was determined using FTIR and GC-MS. The isolated HB1 bacterial strain was identified as Staphylococcus hominis, which is heterotroph.

Analysis and microbial degradation of Low-Density Polyethylene (LDPE) in Winogradsky column

Plastic pollution is threatening the world and the life in it. Cost-effective and eco-friendly treatment is the need of the hour. Treating plastics using chemical methods adds up chemicals into the environment with toxic byproducts. The physical method, a slow and expensive process, is not the better alternative. The process should rely on the environmental sources producing eco-friendly byproducts. The byproducts such as biofuel could be utilized for a sustainable environment, but the conversion of plastics into biofuel is expensive. Hence, biodegradation is the better, sustainable, and cost-effective process for plastic/any other pollutant removal. The study focuses on the construction of Winogradsky column using dumpsite soil. The column amended with Low-Density Polyethylene (LDPE) serves as a carbon source for native microbes. The utilization of microbes in every niche for the degradation enhances the degradation of LDPE. The Otteri soil resulted in 35.4 ± 0.3%, while Kodungaiyur and agriculture soil show 29.7 ± 0.6% and 19.8 ± 0.8%. The AFM analysis shows the disruption of smooth LDPE surface by forming ridges and grooves, which further confirms the occurrence of degradation. The FTIR analysis shows the incorporation of OH, CO, and other CO–O–CO in the CH backbone of LDPE. The oxidation of LDPE will aid in cleavage and result in the process of weathering. The tensile strength decreased after LDPE treatment (23.88 MPa - control, 22.50 MPa – Kodungaiyur, and 14.92 MPa – Otteri). Thus, utilizing the native microbes present in every niche enhances the degradation of pollutants.

Soil concentrations, compositional profiles, sources and bioavailability of polychlorinated dibenzo dioxins/furans, polychlorinated biphenyls and polycyclic aromatic hydrocarbons in open municipal dumpsites of Chennai city, India.

Several studies have reported the release of halogenated persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs) associated with open burning of municipal solid waste. Considering soil as a sink for such organic contaminants, we conducted an in-depth study on the surface soil concentrations of polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs), polychlorinated biphenyls (PCBs) and sixteen USEPA enlisted PAHs collected from thirteen zones of the two major municipal dumpsites, Kodungaiyur dumpsite (KDS) and Perungudi dumpsite (PDS) of Chennai city. Indigenous microbes from dumpsite soil samples were isolated and identified based on 16S rRNA sequencing and phylogenetic analysis. Using indigenous microbes, we have elucidated the bioavailability of the targeted organic pollutants for each site.Range of Σ17PCDD/Fs, Σ25PCBs and ∑16PAHs varied between 3.96-612pg/g (96.0pg/g; median), ND-182ng/g (6.35ng/g; median) and 0.62-3649ng/g (64.3ng/g; median), respectively. All the dumpsite samples showed bioavailability for POPs and PAHs. Toxicity equivalent values (TEQs) associated with dioxin-like PCBs and PCDD/Fs from the zones where dumped municipal solid wastes were collected from electronic-waste/IT-corridor/port areas and toxic PAHs from the zone receiving wastes from the industrial corridor of the city were higher than the soil permissible limit prescribed by the World Health Organization.