共 7 条
Response of size-dependent chemical composition of dissolved organic and inorganic species to land use types in tropical coastal headstreams
被引:2
|作者:
Ji, Hengkuan
[1
]
Wu, Yueying
[1
]
Fu, Peijiao
[2
]
Wu, Zhipeng
[1
]
Li, Caisheng
[1
]
Hou, Zhengwei
[1
]
Chen, Lian
[3
]
Qiu, Yong
[4
]
机构:
[1] Hainan Univ, Coll Trop Crops, Haikou 570228, Peoples R China
[2] Hainan Acad Agr Sci, Vegetable Res Inst, Haikou 571100, Peoples R China
[3] Guangdong Acad Agr Sci, Sericultural & Agrifood Res Inst, Guangzhou 510610, Peoples R China
[4] Quanzhou Normal Univ, Coll Oceanol & Food Sci, Quanzhou 362000, Fujian, Peoples R China
基金:
中国国家自然科学基金;
关键词:
Dissolved organic matter;
Dissolved inorganic matter;
Size distribution;
Headwater streams;
Land use types;
Multiple spectroscopic techniques;
MATTER CHARACTERISTICS;
HUMIC-ACID;
CARBON;
DOM;
RIVER;
CHEMODIVERSITY;
COMPLEXATION;
MECHANISMS;
ABUNDANCE;
PROFILES;
D O I:
10.1016/j.ecolind.2023.110348
中图分类号:
X176 [生物多样性保护];
学科分类号:
090705 ;
摘要:
Land-use types dramatically affect the source, composition, behavior and fate of headstream chemical species. However, the influence of land-use types on the size-dependent composition of dissolved organic matter (DOM) and dissolved inorganic matter (DIM) is still unclear. Here, we evaluated the size-dependent concentration, composition and relationship of chemical species from 9 coastal headstreams (i.e. forested, agricultural and wetland headstreams) using multiple spectroscopic techniques including absorbance, excitation-emission matrix, near-edge X-ray absorption fine structure spectroscopy (NEXAFS), X-ray diffraction (XRD), scanning electron microscopy combined with energy dispersive spectroscopy (SEM-EDS) and synchrotron-based micro-X-ray fluorescence (mu-XRF). Results showed that 68.57%-85.78% of dissolved organic carbon (DOC) with abundant humic/fulvic-like substances were distributed in the <1 kDa fraction in all samples, with a higher percentage in wetland samples. Agricultural land-use increased the export of aluminosilicate minerals in >1 kDa fractions and terrestrial fulvic/humic-like substances from land to stream. Forested streams showed high DOC in the 1 kDa-0.2 mu m fraction, predominance of autochthonous DOM rich in amides, amines, carboxyl and O-alkyl groups, and abundance whitlockite and ferromanganese oxides. Wetland streams were characterized by abundant halite, sylvite, and microbially-transformed humic-like DOM rich in aromatic and phenolic groups. Morphology and correlation analysis implied DIM was closely combined with fluorescent DOM (FDOM) and colored DOM (CDOM), resulting in more irregular organo-inorganic complexes in forested and agricultural streams, and more halite and sylvite crystal blocks encapsulating by smooth and close organic-inorganic complexes in wetland streams. Redundancy analysis (RDA) analysis suggested that land-use types (17.20%) and molecular weight (14.29%) were the prominent factors impacting the composition and relationship of DOM and DIM. Land-use types altered the sources and transport patterns of chemical species in headstreams, influencing their sizedependent compositions and associated biogeochemical processes. Such information is imperative for monitoring and developing land-use policies in coastal regions undergoing intense anthropogenic alterations.
引用
收藏
页数:11
相关论文