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1.
Ying Yong Sheng Tai Xue Bao ; 32(12): 4467-4474, 2021 Dec.
Article in Chinese | MEDLINE | ID: mdl-34951288

ABSTRACT

Understanding the decomposition dynamics and driving factors of manure in the soil subjected to different reclaimed years could provide theoretical basis to rational utilization of manure and soil fertility improvement in coal mining area. Cattle manure and pig manure were mixed with soils subjected to different reclaimed years (one year, R1; 10 years, R10; and 30 years, R30) at the ratio of manure carbon to soil mass of 4 to 100, so as to examine manure decomposition characteristics using the nylon mesh bag (15 cm deep of soil buried) in the Shanxi coal mine reclamation area, with no manure addition as control (CK). Soil samples were collected at day 12, 23, 55, 218, 281, and 365 to measure the contents of soil manure residual, soil microbial biomass carbon (MBC), and dissolved organic carbon (DOC). The contributions of soil properties, manure properties, and hydrothermal condition to manure decomposition were quantified. The results showed that the decomposition rates of pig manure were significantly higher than cattle manure. The humification coefficient of pig manure (average 46.3%) was lower than that of cattle manure (average 71.7%). The humification coefficient of pig manure was significantly lower in the 30-year reclaimed soil (44.5%) compared to the 1-year and 10-year reclaimed soil (average 47.2%). There was no significant difference in the humification coefficient of cattle manure among the three reclaimed soils. The proportion and decomposition rate constant of labile carbon pool of pig manure and cattle manure were significantly different, with values of 52% and 26%, and 0.00085 and 0.00074 ℃-1, respectively. The positive effect of pig manure on MBC and DOC in reclaimed soil was significantly higher than that of cattle manure over 0-218 days, but no difference over 281-365 days. The magnitude of the enhancement of MBC and DOC in those three reclaimed soils after manure amendments showed a similar trend of R1 >R10 ≈ R30. Results of variance partitioning analysis showed that manure decomposition was mainly controlled by manure properties (17.9%) when considering soil properties, manure properties, and hydrothermal condition. In conclusion, the decomposition of pig manure but not cattle manure was regulated by reclamation year. Cattle manure, with higher humification coefficient than pig manure, was recommended for reclaimed mining area to improve soil fertility.


Subject(s)
Coal Mining , Soil , Animals , Carbon/analysis , Cattle , Dissolved Organic Matter , Manure , Mining , Swine
2.
PLoS One ; 15(3): e0229341, 2020.
Article in English | MEDLINE | ID: mdl-32150552

ABSTRACT

Very poor reclaimed soil quality and weak microbial activity occur in the reclamation area of a coal gangue landfill in the Loess Hills. The fourth and fifth years after farmland soil was reclaimed were studied, and the changes in and carbon source utilization characteristics of rhizosphere (R) and non-rhizosphere (S) soil microorganisms under organic and inorganic (OF), inorganic (F), and organic (O) fertilizer application and a control treatment (CK) in soybean (S) and maize (M) rotation systems were compared and analysed in Guljiao Tunlan, Shanxi Province, China. Biolog-EcoPlate technology was used to analyse the mechanism of soil characteristic change from the perspective of soil microbial metabolism function to provide a theoretical basis for reclamation and ecological reconstruction in this area. The average well colour development (AWCD) absorption and Shannon-Wiener index values of soybean and maize rhizosphere microorganisms were higher than those of non-rhizosphere microorganisms, and the mean value of the fertilizer treatment was higher than that for CK. Principal component analysis shows the main carbon sources that impact the functional diversity of the soybean rhizosphere and non-rhizosphere soil communities are a-cyclodextrin, a-D-lactose, ß-methyl D-glucoside, and glucose-1-phosphate and L-phenylalanine, while those for the maize rhizosphere and non-rhizosphere soil communities are D-cellobiose, glucose-1-phosphate, ß-methyl D-glucoside, methyl pyruvate, D-galactosate gamma lactone, D-mannitol, N-acetyl-D-glucosamine, D-galactosalonic acid, and L-serine. The comprehensive utilization score of the non-rhizosphere soil carbon source in the maize season increased with respect to that in the soybean season, and the maximum increase was 1.09 under the OF treatment. Redundancy analysis showed that the soil nutrient factors driving the changes in the metabolic function diversity index values of the rhizosphere and non-rhizosphere soil microbial communities in the different crop seasons in the reclamation area differed, but they were all related to the soil organic matter and available phosphorus. This may explain why OF treatment is the most beneficial to soil fertility under the rotation system in mining reclamation areas.


Subject(s)
Bacteria/metabolism , Biodiversity , Crop Production/methods , Fertilizers , Rhizosphere , Soil Microbiology , Zea mays/growth & development , Bacteria/classification , Coal , Microbiota , Waste Disposal Facilities , Zea mays/drug effects , Zea mays/metabolism , Zea mays/microbiology
3.
Iran J Radiol ; 13(1): e22144, 2016 Jan.
Article in English | MEDLINE | ID: mdl-27110337

ABSTRACT

BACKGROUND: Peripheral nerves at the elbow region are prone to entrapment neuropathies and injuries. To make accurate assessment, clinicians need stereoscopic display of the nerves to observe them at all angles. OBJECTIVES: To obtain a stereoscopic display of the peripheral nerves at the elbow region based on magnetic resonance (MR) diffusion tensor imaging (DTI) data using three post-processing methods of volume rendering (VR), maximum intensity projection (MIP), and fiber tractography, and to evaluate the difference and correlation between them. SUBJECTS AND METHODS: Twenty-four elbows of 12 healthy young volunteers were assessed by 20 encoding diffusion direction MR DTI scans. Images belonging to a single direction (anterior-posterior direction, perpendicular to the nerve) were subjected to VR and MIP reconstruction. All raw DTI data were transferred to the Siemens MR workstation for fiber tractography post-processing. Imaging qualities of fiber tractography and VR/MIP were evaluated by two observers independently based on a custom evaluation scale. RESULTS: Stereoscopic displays of the nerves were obtained in all 24 elbows by VR, MIP, and fiber tractography post-processing methods. The VR/MIP post-processing methods were easier to perform compared to fiber tractography. There was no significant difference among the scores of fiber tracking and VR/MIP reconstruction for single direction. The imaging quality scores of fiber tractography and VR/MIP were significantly correlated based on intraclass correlation coefficient (ICC) analysis (ICC ranged 0.709 - 0.901), which suggested that the scores based on fiber tractography and VR/MIP for the same sample were consistent. Inter- and intraobserver agreements were good to excellent. CONCLUSION: Stereoscopic displays of the peripheral nerves at the elbow region can be achieved by using VR, MIP, and fiber tracking post-processing methods based on raw DTI images. VR and MIP reconstruction could be used as preview tools before fiber tracking to determine whether the raw images are satisfactory.

4.
Eur J Radiol ; 84(6): 1116-27, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25836354

ABSTRACT

OBJECTIVES: To achieve 3-dimensional (3D) display of peripheral nerves in the wrist region by using maximum intensity projection (MIP) post-processing methods to reconstruct raw images acquired by a diffusion tensor imaging (DTI) scan, and to explore its clinical applications. METHODS: We performed DTI scans in 6 (DTI6) and 25 (DTI25) diffusion directions on 20 wrists of 10 healthy young volunteers, 6 wrists of 5 patients with carpal tunnel syndrome, 6 wrists of 6 patients with nerve lacerations, and one patient with neurofibroma. The MIP post-processing methods employed 2 types of DTI raw images: (1) single-direction and (2) T2-weighted trace. The fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values of the median and ulnar nerves were measured at multiple testing sites. Two radiologists used custom evaluation scales to assess the 3D nerve imaging quality independently. RESULTS: In both DTI6 and DTI25, nerves in the wrist region could be displayed clearly by the 2 MIP post-processing methods. The FA and ADC values were not significantly different between DTI6 and DTI25, except for the FA values of the ulnar nerves at the level of pisiform bone (p=0.03). As to the imaging quality of each MIP post-processing method, there were no significant differences between DTI6 and DTI25 (p>0.05). The imaging quality of single-direction MIP post-processing was better than that from T2-weighted traces (p<0.05) because of the higher nerve signal intensity. CONCLUSIONS: Three-dimensional displays of peripheral nerves in the wrist region can be achieved by MIP post-processing for single-direction images and T2-weighted trace images for both DTI6 and DTI25. The FA and ADC values of the median nerves can be accurately measured by using DTI6 data. Adopting 6-direction DTI scan and MIP post-processing is an efficient method for evaluating peripheral nerves.


Subject(s)
Diffusion Tensor Imaging/methods , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Peripheral Nerves/pathology , Peripheral Nervous System Diseases/diagnosis , Wrist/pathology , Adult , Anisotropy , Female , Humans , Male , Observer Variation , Peripheral Nerves/anatomy & histology , Reproducibility of Results , Wrist/anatomy & histology , Young Adult
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