scholarly journals Using the HPTLC-bioluminescence bacteria assay for the determination of acute toxicities in marine sediments and its eligibility as a monitoring assessment tool

Chemosphere ◽  
2019 ◽  
Vol 233 ◽  
pp. 936-945 ◽  
Author(s):  
Anna Logemann ◽  
Michaela Schafberg ◽  
Berit Brockmeyer
Keyword(s):  
Marine Sediments ◽  
Assessment Tool ◽  
Bioluminescence Bacteria

scholarly journals Drought Propagation Patterns under Naturalized Condition Using Daily Hydrometeorological Data

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Jianzhu Li ◽  
Yuangang Guo ◽  
Yixuan Wang ◽  
Shanlong Lu ◽  
Xu Chen
Keyword(s):  
Early Warning ◽  
Assessment Tool ◽  
Swat Model ◽  
Meteorological Drought ◽  
Threshold Level ◽  
Hydrological Drought ◽  
Propagation Pattern ◽  
Drought Early Warning ◽  
Hydrological Droughts

Drought propagation pattern forms a basis for establishing drought monitoring and early warning. Due to its regional disparity, it is necessary and significant to investigate the pattern of drought propagation in a specific region. With the objective of improving understanding of drought propagation pattern in the Luanhe River basin, we first simulated soil moisture and streamflow in naturalized situation on daily time scale by using the Soil and Water Assessment Tool (SWAT) model. The threshold level method was utilized in identifying drought events and drought characteristics. Compared with meteorological drought, the number of drought events was less and duration was longer for agricultural and hydrological droughts. The results showed that there were 3 types of drought propagation pattern: from meteorological drought to agricultural/hydrological drought (M-A/H), agricultural/hydrological drought without meteorological drought (NM-A/H), and meteorological drought only (M). To explain the drought propagation pattern, possible driven factors were determined, and the relations between agricultural/hydrological drought and the driven factors were built using multiple regression models with the coefficients of determination of 0.4 and 0.656, respectively. These results could provide valuable information for drought early warning and forecast.

SULFUR IN A FOSSIL WOOD FROM THE PLEISTOCENE MARINE CLAY

2004 ◽  
Vol 14 (01n02) ◽  
pp. 67-73
Author(s):  
K. KAGEMORI ◽  
N. AIKAWA ◽  
K. ISHIMARU ◽  
S. KAWAI ◽  
M. YUKAWA ◽  
...  
Keyword(s):  
Humic Substances ◽  
Sulfur Content ◽  
Marine Sediments ◽  
Crucial Role ◽  
Fossil Wood ◽  
Total Sulfur ◽  
Marine Clay ◽  
Polarizing Microscopy ◽  
Wood Tissue

In anoxic marine sediments sulfur is considered to be essential to the formation of humic substances. It is also estimated that sulfur may play a crucial role in the degradation of wood buried in marine sediments. In order to confirm this prediction, we observed the tissue of fossil wood from the marine clay aged 1.1 million years by polarizing microscopy and SEM before the determination of its sulfur content by PIXE and EDXA, and its distribution by μ-PIXE. Results show that the sample contained about 6000 μg/g of total sulfur and tracheid cells with birefringence, which have probably preserved the original wood components contain less sulfur compared to those without birefringence, which are heavily degraded. This might suggest the participation of sulfur in the degradation or the formation of humic substances occurred in wood tissue during diagenesis.

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