Study on the spectral and Cu (II) binding characteristics of DOM leached from soils and lake sediments in the Hetao region.
BACKGROUND
Dissolved organic matter (DOM) is the most active component in environmental system and its chemical and structural characteristics most likely influence its biodegradation. Four surface soil (0-20 cm) and three core sediment samples (0-10 cm) were collected from Wuliangsuhai Lake. The objectives of this study were to investigate the spectral properties and humification degree of DOM and to determine and discuss comparatively the complexing capacities and stability constants of DOM by Cu (II) in the Hetao region.


METHODS
In this study, fluorescence spectra and fluorescence quenching methods were used to evaluate the humification degree of DOM and calculate the complexing capacities and the stability constants between DOM and Cu (II).


CONCLUSIONS
Two defined peaks, at wavelengths of 260∼300 nm (peak I) and 300∼350 nm (peak II), could be identified for soil DOM at a Δλ value of 30 nm. In sediment DOM extracts, a third peak (III) was observed near 364 nm. The results show that there is a significant difference in the structure of DOM because of different sources. The humification degree is significantly higher for soil samples than those of sediment samples. The FT-IR spectra of DOM show that structure in sediment DOM is more functional groups than those in soil DOM. DOM has a stronger Cu binding affinity in soils than in sediment in the Hetao region, which may lead to potentially significant influence on the migration and transformation of Cu (II).
Key Laboratory of Energy Microbiology and Application, Biogas Scientific Research Institute of the Ministry of Agriculture, Chengdu 610041, China. gxj530520@126.com
Xujing
X
Guo
Jinyuan
J
Jiang
Beidou
B
Xi
Xiaosong
X
He
Hui
H
Zhang
Yu
Y
Deng
D002681:China; D003300:Copper / Q000737:chemistry*; D019015:Geologic Sediments / Q000032:analysis; D060106:Lakes; D012987:Soil / Q000032:analysis; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry*
D012987:Soil; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical; D003300:Copper