organic matter content
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2022 ◽  
Vol 28 ◽  
pp. e00461
Author(s):  
Alvaro José Gomes de Faria ◽  
Sérgio Henrique Godinho Silva ◽  
Renata Andrade ◽  
Marcelo Mancini ◽  
Leônidas Carrijo Azevedo Melo ◽  
...  

Author(s):  
S. Korkmaz ◽  
R. Kara-Gülbay ◽  
T. Khoitiyn ◽  
M. S. Erdoğan

AbstractThe Cenozoic Çankırı-Çorum basin, with sedimentary facies of varying thickness and distribution, contains raw matters such as coal deposits, oil shales and evaporate. Source rock and sedimentary environment characteristics of the oil shale sequence have been evaluated. The studied oil shales have high organic matter content (from 2.97 to 15.14%) and show excellent source rock characteristics. Oil shales are represented by very high hydrogen index (532–892 mg HC/g TOC) and low oxygen index (8–44 mgCO2/g TOC) values. Pyrolysis data indicate that oil shales contain predominantly Type I and little Type II kerogen. The biomarker data reveal the presence of algal, bacterial organic matter and terrestrial organic matter with high lipid content. These findings show that organic matters in the oil shales can generate hydrocarbon, especially oil. High C26/C25, C24/C23 and low C22/C21 tricyclic terpane, C31R/C30 hopane and DBT/P ratios indicate that the studied oil shales were deposited in a lacustrine environment, and very low Pr/Ph ratio is indicative of anoxic character for the depositional environment. Tmax values from the pyrolysis analysis are in the range of 418–443 °C, and production index ranges from 0.01 to 0.08. On the gas chromatography, high Pr/nC17 and Ph/nC18 ratios and CPI values significantly exceeding 1 were determined. Very low 22S/(22S + 22R) homohopane, 20S/(20S + 20R) sterane, diasterane/sterane and Ts/(Ts + Tm) ratios were calculated from the biomarker data. Results of all these analyses indicate that Alpagut oil shales have not yet matured and have not entered the oil generation window.


2022 ◽  
Vol 14 (2) ◽  
pp. 805
Author(s):  
Tianjing Ren ◽  
Yu’e Li ◽  
Tiantian Miao ◽  
Waseem Hassan ◽  
Jiaqi Zhang ◽  
...  

Excessive nitrogen fertilizer application in greenhouses could cause a significant variation in the nitrogen-use efficiency at the regional scale. This study aims to quantify agronomic nitrogen-use efficiency (AEN) and identify its driving factors across Chinese greenhouse tomato cultivation. Three hundred and forty-eight AEN values were obtained from 64 papers, including mineral nitrogen (MN) and mineral combined with organic nitrogen (MON) treatments. The average AEN values for the MN and MON treatments were 56.6 ± 7.0 kg kg−1 and 34.6 ± 3.5 kg kg−1, respectively. The AEN of the MN treatment was higher than that of the MON treatment for cultivation using soil with an organic matter content of less than 10 g kg−1 and the drip fertigation method. The AENs of the MN and MON treatments were divided into two segments according to the nitrogen application rate. The inflection points of the nitrogen application rate were 290 and 1100 kg N ha−1 for the MN and MON treatments, respectively. When the ratio of organic nitrogen to total nitrogen was less than 0.4, it was beneficial for improving the AEN. The soil organic matter content and the nitrogen application rate were the most critical factors determining the AEN. These results suggest that rationally reducing the nitrogen input and partially substituting mineral nitrogen with organic nitrogen can help improve the nitrogen-use efficiency.


Separations ◽  
2022 ◽  
Vol 9 (1) ◽  
pp. 12
Author(s):  
Renli Ma ◽  
John R. Dean

The former St. Antony’s Lead Works site, now the central part of an urban recreational park (Walker Riverside Park) in the east end of Newcastle upon Tyne (England, UK), has been assessed based on the Pb concentration in topsoil according to recently derived Category 4 Screening Level (C4SL) for public open space–park (POSpark, 1300 mg/kg). The site was divided into eight sampling areas following its physical layout. In total 79 soil samples were collected, characterised for acidity and organic matter content, and analysed by energy dispersive X-ray fluorescence (ED-XRF). The Pb levels in most of the samples, particularly those from the fringes of the site, are below the generic guideline value (down to 70 mg/kg). More than 16% of the samples from nearly all sampling areas, especially those sampling points around the former horizontal condenser flue and main chimney, contain levels of Pb significantly exceeding the limit (up to 206,000 mg/kg). No correlation is found between the Pb concentration in soil samples and their acidity (mostly neutral, pH 7.0 ± 0.5) or organic matter content (15.5 ± 4.1%). Using the Contaminated Land Exposure Assessment (CLEA) model (version 1.071), the site-specific risk assessment criteria (SSAC) for Lead (C4SL child), 2862 mg/kg, is obtained based on adjusted exposure frequency and occupancy period. Nearly 9% of the individual sample Pb concentrations (n = 79) across sample locations B, C, D and H are still above the specific value. Further statistical evaluation based on 95% upper confidence limit confirms that the site still represents a potential human health risk. This is because Pb concentrations, from two areas in the centre of the site (sample locations B and C), are greatly over the SSAC specific threshold (sample mean at location B is 12,350 mg/kg and at location C is 11,745 mg/kg).


2022 ◽  
Vol 43 (1) ◽  
pp. 7-24
Author(s):  
Iris Mariane da Silva Martins ◽  
◽  
Tatiane Carla Silva ◽  
Maria Julia Betiolo Troleis ◽  
Paulino Taveira de Souza ◽  
...  

Effects of soil attributes using the geostatistical tool improves the interpretation of specific soil management. Thus, this study aimed to evaluate the physical, chemical, and microbiological properties of a Typical Haplustox (Oxisol), identifying those with the best linear and spatial correlation with eucalyptus (Eucalyptus spp.) vegetative growth. The experiment was conducted at the Teaching, Research, and Extension Farm (FEPE) of the Universidade Estadual Paulista (UNESP), Campus of Ilha Solteira. Thirty-five points spaced 13 meters apart were demarcated for analysis, which were distributed in 5 rows of 7 points each. From each point, 2 soil samples were collected from the 0-10 cm depth layer. The physical, chemical, and microbiological soil properties evaluated were: sand, silt, and clay contents; penetration resistance (PR), gravimetric moisture (GM), real density (RD), microbial biomass carbon (MBC), respirometry (CO2-C), metabolic quotient (qCO2), organic matter content (OM), and hydrogenionic potential (pH). The eucalyptus attributes assessed were: plant height (PH) and circumference at breast height (CBH). Each attribute was analyzed by descriptive statistics using the SAS software. Data frequency distribution was verified by the Shapiro Wilk method, and geospatial changes were analyzed by the GS+ software. The soil property that best explained the variability in eucalyptus dendrometric attributes was real density (RD). Except for RD, all properties did not show spatial dependence (i.e., pure nugget effect), which significantly represents eucalyptus vegetative performance.


Author(s):  
S Chowdhury ◽  
D Chakraborty ◽  
MK Rahman

Fifteen soil samples (0-15cm depth) and fifteen betel leaf samples from Bara Moheshkhali, Choto Moheshkhali, Hoanak, Kalmarchora, Shaplapur union of Moheshkhali upazila, Cox’s Bazar district were collected on December-January (2020-2021). It was collected for the purpose of evaluating the color, particle density, moisture content, texture, pH, EC and organic matter content of soils and total nitrogen, phosphorous, potassium and sulfur of the soils and total protein content, nitrogen, phosphorus, potassium and sulfur of leaves. Maximum sampled soil was containing yellowish red color when moist and showed brown color when dried. Some of them were flood plain soil and that’s why showed grey color during dry and moist condition. Mean particle density was 2.49 g/cm3 and mean moisture content was 13.95%. Average sand, silt and clay were 65.08%, 18.56% and 19.26%, respectively. The texture of the soils was sandy loam to clay loam. The sand was by far the dominant fraction in the soils. Mean pH value was 5.63, organic matter was 0.30% and EC was 99.38μS/cm. Mean total nitrogen, phosphorus, potassium and sulfur of the soils were 0.04, 0.46, 0.25 and 0.26%, respectively. The mean concentration of protein, nitrogen, phosphorus, potassium and sulfur in the betel leaf samples were 20.56, 3.29, 0.39, 0.79 and 0.20%, respectively. This investigation focuses on the fertility status and physico-chemical properties of soil in betel leaf garden of only hilly island of Bangladesh, Moheshkhali. J. Biodivers. Conserv. Bioresour. Manag. 2021, 7(1): 25-32


2022 ◽  
Vol 8 (1) ◽  
pp. 65
Author(s):  
Giulio Barone ◽  
Cinzia Corinaldesi ◽  
Eugenio Rastelli ◽  
Michael Tangherlini ◽  
Stefano Varrella ◽  
...  

Fungi are a ubiquitous component of marine systems, but their quantitative relevance, biodiversity and ecological role in benthic deep-sea ecosystems remain largely unexplored. In this study, we investigated fungal abundance, diversity and assemblage composition in two benthic deep-sea sites of the Ross Sea (Southern Ocean, Antarctica), characterized by different environmental conditions (i.e., temperature, salinity, trophic availability). Our results indicate that fungal abundance (estimated as the number of 18S rDNA copies g−1) varied by almost one order of magnitude between the two benthic sites, consistently with changes in sediment characteristics and trophic availability. The highest fungal richness (in terms of Amplicon Sequence Variants−ASVs) was encountered in the sediments characterized by the highest organic matter content, indicating potential control of trophic availability on fungal diversity. The composition of fungal assemblages was highly diverse between sites and within each site (similarity less than 10%), suggesting that differences in environmental and ecological characteristics occurring even at a small spatial scale can promote high turnover diversity. Overall, this study provides new insights on the factors influencing the abundance and diversity of benthic deep-sea fungi inhabiting the Ross Sea, and also paves the way for a better understanding of the potential responses of benthic deep-sea fungi inhabiting Antarctic ecosystems in light of current and future climate changes.


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