Temporal and spatial distribution characteristics and source analysis of dissolved organic nitrogen in the surface sediment of the Caohai Lake, southwest China

Yan, Xinting; Liao, Jia-Hao; Cao, Xingxing; Han, Zhiwei

doi:10.1007/s11356-022-22953-6

Cited by 2 publications

(1 citation statement)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The first two peaks are identified as humic acid-like substances, primarily originating from human activities such as agricultural practices [38]. The third fluorescence peak indicates tyrosine, a protein primarily derived from internal biodegradation processes [50]. The FI of the RCIS-5 spectra is significantly lower than RM and RCIS-2, detecting only the peak corresponding to tyrosine peak near (Ex, Em) = (275, 310).…”

Section: Eem Spectra Of the Dom Fractionsmentioning

confidence: 99%

Variation in the Content and Fluorescence Composition of Dissolved Organic Matter in Chinese Different-Term Rice–Crayfish Integrated Systems

Liu,

Huang,

Chen

et al. 2024

Sustainability

View full text Add to dashboard Cite

This study examines the fluorescence characteristics of dissolved organic matter (DOM) in soils from different periods of rice–crayfish integrated systems (RCISs) in China. Utilizing three-dimensional excitation–emission matrix (3D-EEM) fluorescence spectroscopy, the study investigated the hydrophobicity, molecular weight distributions, and fluorescence properties of DOM in 2-, 5-, and 7-year RCIS operations, with rice monoculture (RM) serving as a control. The findings indicate that in the initial 2 years of an RCIS, factors such as rice straw deposition, root exudates, and crayfish excretions increase dissolved organic carbon (DOC) release and alter DOM composition, increasing the humic acid content in the soil. As the system matures at 5 years, improvements in soil structure and microbial activity lead to the breakdown of high-molecular-weight humic substances and a rise in small-molecular-weight amino acids. By the 7-year mark, as the aquatic ecosystem stabilizes, there is an increase in humic substances and the humification index in the soil DOM. These variations in DOM properties are essential for understanding the effects of integrated farming systems on soil quality and sustainability.

show abstract

Section: Eem Spectra Of the Dom Fractionsmentioning

confidence: 99%

Variation in the Content and Fluorescence Composition of Dissolved Organic Matter in Chinese Different-Term Rice–Crayfish Integrated Systems

Liu,

Huang,

Chen

et al. 2024

Sustainability

View full text Add to dashboard Cite

show abstract

Seasonal variation characteristics of water quality in the Sunxi River Watershed, Three Gorges Reservoir Area

Hou

Wang

Zheng

et al. 2022

PeerJ

View full text Add to dashboard Cite

The seasonal change characteristics of water quality in the Sunxi River watershed, which is a typical watershed in the tail area of the Three Gorges Reservoir Area, must be studied to provide remediation ideas and specific measures for agricultural nonpoint source pollution in the reservoir area. A two-way repeated measures ANOVA was used to analyze the variation characteristics of chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) concentrations in the upstream and downstream of the Sunxi River watershed in spring, summer, and autumn of 2018–2021. With data from autumn 2018 taken as an example, path analysis was applied to study the effect degree of influencing factors on TN concentrations. The two-way repeated measures ANOVA illustrated that the COD, TN, and TP concentrations in the downstream were significantly higher than those in the upstream (P < 0.05). In addition, the COD concentrations were the highest in summer 2019, followed by spring of 2019 and 2021, and TN and TP concentrations were higher in spring and summer. The TN and TP concentrations were comparatively lower in the autumn. The path analysis showed that electrical conductance and dissolved oxygen directly affected the TN concentrations, and water temperature mainly affected the TN concentrations via the indirect effects of electrical conductance and dissolved oxygen. The water quality of upstream Sunxi River watershed was better than that of downstream, and the water quality in autumn was better than spring and summer in 2018–2021. For water quality management and ecological restoration of the Sunxi River watershed, further attention should be paid to the water quality changes in the downstream and in spring and summer and to the impact of water temperature, electrical conductivity, and dissolved oxygen on the water quality.

show abstract

Temporal and spatial distribution characteristics and source analysis of dissolved organic nitrogen in the surface sediment of the Caohai Lake, southwest China

Cited by 2 publications

References 45 publications

Variation in the Content and Fluorescence Composition of Dissolved Organic Matter in Chinese Different-Term Rice–Crayfish Integrated Systems

Variation in the Content and Fluorescence Composition of Dissolved Organic Matter in Chinese Different-Term Rice–Crayfish Integrated Systems

Seasonal variation characteristics of water quality in the Sunxi River Watershed, Three Gorges Reservoir Area

Contact Info

Product

Resources

About