Alterações nas propriedades químicas e microbianas de solos cultivados com videiras sob manejo orgânico e convencional no sul do Brasil

O cultivo orgânico com inclusão de material orgânico fresco altera propriedades físicas e químicas do solo e, com isso, pode resultar em modificações nas características biológicas deste. Assim, o objetivo deste estudo foi estudar os efeitos do manejo da videira (Vitis labrusca L.) sobre as propriedades químicas e microbianas do solo. Em outubro de 2006, amostras de solo foram coletadas de dois experimentos instalados em 2000 e de uma área adjacente com floresta. Os seguintes tratamentos foram avaliados em um esquema fatorial 2 x 2 x 2: (i) orgânico (ORG) e convencional (CONV); (ii) dos cultivares (IAC-766/Isabel e IAC-766/Bordô); e (iii) da heterogeneidade espacial (linha e entrelinha) sobre as propriedades químicas e microbianas de um solo arenoso. Foi observada a formação de três grandes grupos (CONV, ORG/linha e ORG/entrelinha), que se destacaram na área de floresta. As variáveis químicas e microbianas, com exceção do K, foram alteradas em relação aos manejos da videira. Houve efeitos do cultivar no N da biomassa microbiana e na respiração basal (CO2). Também foram observados efeitos de heterogeneidade espacial do solo no C da biomassa microbiana e em atributos químicos, como P, pH, Mg e micronutrientes. No sistema orgânico da videira, aumentaram-se o carbono orgânico do solo (COS) e a biomassa microbiana na linha e entrelinha, em comparação com a videira convencional. Os aumentos foram de 172 % no SOC, 100 % no Cmic e 223 % no Nmic, na linha do orgânico. Os manejos da videira e a heterogeneidade espacial do solo foram os fatores mais relevantes no agrupamento (ou separação) das áreas devido às mudanças nos atributos químicos do solo, principalmente o COS, e na biomassa microbiana

Indoor Quality of Residential Homes and Schools of an Industrial Area in Asansol: Characterization, Bioaccessibility and Health Risk Assessment of Potentially Toxic Elements

Bioaccessibility of eight potentially toxic elements (PTEs), their human exposure and health risk assessments were determined in the indoor dust of residence and schools from the Asansol Industrial area, India. The PTEs concentrations were maximum during the winter both at houses and schools. The average PTEs concentrations throughout the year in Asansol were 3.16, 120, 156, 41708, 2354, 61.3, 115 and 345 mg.kg-1 for Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn respectively. X-ray powder diffraction indicated an abundance of quartz in the indoor dust. Principal component analysis (PCA) indicated multiple sources such as traffic, industries, and lithogenic sources for PTEs in indoor dust. Percentage of bioaccessibility was maximum for Cd (55.3% throughout the year). Total PTEs concentration and a bioaccessible fraction of PTEs both were used for health risk assessment, and non-carcinogenic health risk was <1 for total PTEs and the bioaccessible fraction of PTEs. Health risk of total PTEs’ (HItotal) for Mn was high for both children and adult (6.76E-01 and 1.3E-01, respectively). Monte Carlo simulation model indicated that all the cumulative probability of Hazard Quotient (HQ) for collectively eight metals was below 1

Potassium Influencing Physiological Parameters, Photosynthesis and Sugarcane Yield in Subtropical India

Potassium plays an important role in the metabolism of plants, growth, development and yields. Worldwide, KCl is commonly used as source of K fertilizer in agricultural crops. The present experiment was taken up to assess the response of various sources of K on physiological attributes, yield and quality parameters of sugarcane. Treatments were no K application, potassium ammonium sulphate (H4KNO4S-9:0:30:20, NPKS ratio), slow release K fertilizer (0:0:45:0), sulphate of potash/potassium sulphate (K2SO4-0:0:50:17.5), muriate of potash (KCl-0:0:50:0) and muriate of potash (KCl) + elemental S @ 40 kg ha−1. Application of K2SO4 recorded 15.8% improvement in tiller population (during peak tillering stage) and 22.2% improvement in dry matter accumulation (at the harvest stage) over the KCl. About 12.33–24.16% increments in crop growth rate and the highest net photosynthetic rate (19.91 µmol m−2 s−1) were also recorded with application of K2SO4. Application of K fertilizers improved the availability of potassium in soil by 8.17% (254.2 kg ha−1). Potassium uptake in sugarcane crop ranged from 245 to 347 kg ha−1. The highest individual cane length (311 cm) was measured with application of K2SO4. Application of K2SO4 brings forth about 23.8% increments in millable canes, 14% in cane weight and 33.8% in cane yield over no K. Application of K also increased mean sucrose content in juice by 0.58 unit (17.0 pol per cent juice) over no use of K. Overall effect of K application on increasing sugarcane yield and sucrose content simultaneously brought forth improvement in commercial cane sugar (CCS) by 29.43% (10.50 t/ha) over no use of K. However, application of K2SO4 also improved CCS by 25.89% (11.67 t/ha) over the application of KCl

Biodegradation of anthracene by a newly isolated bacterial strain, Bacillus thuringiensis AT .ISM .1, isolated from a fly ash deposition site

The current study is aimed to evaluate the mechanism of anthracene degradation by a bacterial strain isolated from fly ash deposition site near Jamadoba Coal Preparation Plant, Jharkhand, India. The Bushnell‐Haas media cultured (containing anthracene as sole carbon source) bacterial isolate was identified by 16S rRNA gene sequence coding as the Bacillus thuringiensis strain, which showed the efficiency to degrade anthracene. The degradation efficiency of the strain has been estimated to be around 91% (for 40 mg l−1 of anthracene concentration) after 2 weeks of incubation at 33–36°C and initial pH of 6•8–7. The growth kinetics of the isolated strain has been described well by the Haldane–Andrews model of microbial growth pattern for inhibitory substrate, with a correlation factor (R 2 value) of 0•9790. The maximum specific growth rate (μ max) was 0•01053 h−1 and the value of inhibition coefficient for Haldane model was specified as 18•2448 mg l−1. In the present study, some diphenol metabolites were identified besides the known possible biodegradation products

Pollution evaluation, spatial distribution, and source apportionment of trace metals around coal mines soil: the case study of eastern India

The degradation of land by trace metals contamination around coal mining areas is a serious environmental issue, and therefore, it is necessary to have detailed information about the pollution caused by them and their sources. The objective of the work was to study the impact of trace metals (e.g., Cd, Co, Ni, Cr, Zn, Pb, and Cu) on the soil of Jharia coalfield to analyze their sources, contamination level, and their spatial distribution. The present values of the trace metals were compared by their natural background values which were then analyzed on the scale of the Potential Ecological Risk Index (PERI) and by Improved Nemerow Index (Lnm). The results of spatial distribution revealed that the majority of the soil in Jharia coalfield is moderately contaminated, a small portion of it is slightly contaminated, and altogether at moderate ecological risk due to trace metals. Multivariate statistical techniques including Principal component analysis, Cluster analysis, and Pearson’s correlation evaluated that Cu, Ni, Zn, Co, and Cr in the soil samples had the same source which is coal mining; Pb and Cd were from multiple sources. The spatial distribution maps of trace metals present in the soil of Jharia coalfield were generated using Radial basis function an interpolation method

Biofilm development of Bacillus thuringiensis on MWCNT buckypaper: Adsorption-synergic biodegradation of phenanthrene

Adsorption-synergic biodegradation of a model PAH (phenanthrene, Phe) on MWCNT buckypaper surface with a potential PAH biodegrading bacterial strain Bacillus thuringiensis AT.ISM.11 has been studied in aqueous medium. Adsorption of Phe on buckypaper follows Dubinin-Ashtakhov model (R2 = 0.9895). MWCNT generally exerts toxicity to microbes but adsorbed layer of Phe prevents the direct contact between MWCNT and bacterial cell wall. FESEM study suggests that formation of biofilms occurred on buckypaper. Lower layer cells are disrupted and flattened as they are in direct contact with MWCNT but the upper layer cells of the developed biofilm are fully intact and functional. Force-distance curves of Bacillus thuringiensis AT.ISM.11 with buckypaper indicates adhesion forces varied from −10.3 to −15.6 nN with increasing contact time, which supports the phenomenon of biofilm formation. AFM surface statistical data of buckypaper suggests increase in bacterial cell count increases the Rms roughness (95.7242–632.565) while adhering to the buckypaper surface to form biofilm. We observed an enhanced Phe biodegradation of 93.81% from that of the 65.71% in 15 days’ study period, using buckypaper as a bio-carrier or a matrix for the microbial growth. GC-MS study identified phthalic acid ester as metabolite, which is the evidence of protocatechuate pathway degradation of Phe. Current study enlightens the interaction between hydrocarbons and microbes in presence of MWCNT buckypaper matrix in aqueous system for the first time. An enhancement in biodegradation of Phe by 28.10% has also been reported which can be a basis for CNT aided enhanced biodegradation studies in future

Effect of fly ash on carbon mineralization of biochar and organic manures added to mine spoil

Mine spoil is deprived of organic carbon. Reclamation and re-vegetation of mine spoil initiate photosynthetic carbon fxation and add soil organic matter. Fly ash (FA) generated from coal-fred power stations can be used for reclamation of mine spoil. Our research was aimed to assess the efect on FA on carbon mineralization of organic manures and biochar added to mine spoil. Incubation experiments were conducted to assess the carbon mineralization of farmyard manure (FYM), chicken litter (CL), plant litter (PL), and biochar (BC) added to mine spoil in the presence and absence of FA. After 1 year of incubation, the cumulative CO2 emission was lower for the FA-added mine spoil and it was higher for PL (4.42 vs. 5.09 g CO2–C/kg soil, with and without FA, respectively) and CL (3.75 vs. 4.07 g CO2–C/kg soil) followed by FYM (1.86 vs. 1.97) and BC (0.67 vs. 0.54 g CO2–C/kg soil). The labile C pool was signifcantly lower for FA-added mine spoil, whereas the stable carbon pool was higher in FA-added soils: FYM (1.4 vs. 0.6 g CO2–C/kg soil) and CL (2.20 vs. 3.17 g CO2–C/kg soil). Substrate-induced respiration, microbial biomass carbon (MBC), and dissolved organic carbon (DOC) were signifcantly higher under PL, CL, and FYM. FA increased MBC, but decreased DOC. Overall, FA decreased CO2 emission from mine spoil probably due to the interaction of organic matter with the surfaces on FA and the resultant physical protection against microbial decomposition

Exposure and cancer risk assessment of polycyclic aromatic hydrocarbons (PAHs) in the street dust of Asansol city, India

The sources, distribution and total concentration of 16 polycyclic aromatic hydrocarbons (PAHs) in 15 urban street dust samples (each for summer, winter and monsoon season) from Asansol, an industrial city were investigated to evaluate and understand the carcinogenic risk of urban inhabitants exposed to street dust. The results showed that the total PAHs (∑PAHs) in urban street dust at Asansol ranged from 1708± 1345 ng/g to 9688 ± 3257 ng/g with an average value of 4532 ± 2031 ng/g. The 2-ring to 3-ring PAHs dominated in winter; whereas 5-ring to 6-ring PAHs contributed maximum in summer. Principal component analysis (PCA) and ratio determination were performed to identify the potential sources of PAHs. Anth/(Phe + Anth), BaP/BghiP, Fla/(Pyr + Fla), IP/(IP + BghiP), Flt/Pyr, Phen/Anth, and BaA/Chry ratios indicated mixed sources of PAHs. Our result concluded that at Asansol, biomass combustion, coal combustion, traffic emission (gasoline and diesel powered vehicles), thrash burning and domestic coal utilization activity, along with temperature and meteorological dependent played an important role in controlling the distribution of PAHs in street dust. According to the Incremental Lifetime Cancer Risk (ILCR) model, the total cancer risk for children and adults were maximum at industrial sites, i e., 1.4E-05 and 1.5E-05 respectively

Evaluation of the Fuel Value and Soil Application Potential of the Cadmium Contaminated Biochar Obtained after Water Treatment

Spent biochar obtained after water treatment especially metal adsorption could be used as a solid fuel. In this study, soil application potential and fuel value of cadmium contaminated biochar was investigated. Biochar prepared from Parthenium (PBC) and the thermally modified biochar (MPBC) was artificially contaminated with different concentrations (1, 10, 50, 100 and 200 mg/l) of Cd solution. The contaminated PBC-Cd and MPBC-Cd was applied to a red soil, and their impact on soil biological activity, maize growth and Cd bioaccumulation was assessed. Maize growth was retarded due to the contaminated biochar. Soil and plant Cd concentrations increased significantly. The soil dehydrogenase (DHA) and fluorescein diacetate hydrolases enzyme activities were adversely affected. DHA reduced from 324 to 97 mg TPF/kg/24 h in MPBC-1 to MPBC-200, while in PBC-1 to PBC-200, DHA decreased from 422 to 112 mg TPF/kg/24 h. Cd contaminated biochars obtained after waste water treatment could not be used for soil application. Fuel values of contaminated biochar were analysed by the higher heating value of biochars and their fusibility indices. The high heating value of the biochar is comparable with the lignite. Raw biochar contains significant amount of alkali elements that affected their use as a fuel. However after adsorption, the washing of the biochar alkalies significantly improved the fuel properties, especially the propensity for slagging and fouling. Biochar used for treatment of contaminated waste water could be sustainably used as a solid fuel; however further studies are needed to manage the metal enriched ash generated after combustion of these contaminated biochar