Occurrence, transportation, and distribution difference of typical herbicides from estuary to bay
Autor: | Xiang Gu, Baodong Wang, Ming Xin, Yu Zhang, Mats Tysklind, Chunye Lin, Wei Ouyang |
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Jazyk: | angličtina |
Rok vydání: | 2019 |
Předmět: |
Pollution
Geologic Sediments Toluidines 010504 meteorology & atmospheric sciences media_common.quotation_subject Diffuse pollution Distribution (economics) Oceanografi hydrologi och vattenresurser 010501 environmental sciences Suspended particulate sediment 01 natural sciences Oceanography Hydrology and Water Resources chemistry.chemical_compound Phase partition Water Movements Acetochlor Atrazine lcsh:Environmental sciences 0105 earth and related environmental sciences General Environmental Science media_common Hydrology lcsh:GE1-350 geography geography.geographical_feature_category Herbicides business.industry Estuary mienclosed bay Bays chemistry Environmental science Estuaries business Bay Water Pollutants Chemical Environmental Monitoring |
Zdroj: | Environment International, Vol 130, Iss, Pp-(2019) |
ISSN: | 0160-4120 |
Popis: | In several watersheds, agricultural activities are the cause of pollution, mainly due to the discharge of herbicides. Often, these herbicide plumes are transported to the surrounding bays. Samples of water, suspended particulate sediments (SPSs), and sediments from 37 sites in the Jiaozhou Bay in the western Pacific Ocean were collected in April 2018. The total concentrations of atrazine and acetochlor in these samples were analyzed, that showed different patterns in each sampled area. Atrazine had 2–3 times higher concentrations in coastal areas and bays compared to the estuary, indicating that it had a higher residence time in the marine environment. In contrast, acetochlor concentration decreased with an increase in the depth of seawater. Both the spatial distributions and the vertical concentrations in water, SPS, and sediment proved that these two herbicides had different responses during transportation from the estuary to the bay. Despite the significant difference in concentration of the two herbicides in the water and sediment, their spatially averaged value in SPS was very close, indicating that the particles had saturated sorption capability. The organic carbon normalized partition coefficient (LogKoc) was used to explain the partitioning of the herbicides between water and sediment. The LogKoc difference between herbicides demonstrated that acetochlor was strongly phase partitioned in the coastal and the bay areas, thereby causing similar distributions of acetochlor in the three matrices. Atrazine had a higher LogKoc value in the estuary, which explained its higher concentration in the estuary SPS. The correlation and redundancy analyses both demonstrated that the concentrations of the herbicides in water were sensitive to dissolved organic carbon and dissolved oxygen. The current tides and bathymetry were the critical factors in determining the spatial distribution of herbicides in the water and sediment, resulting in a low herbicide load in the river mouth area. Keywords: Atrazine, Acetochlor, Phase partition, Diffuse pollution, Suspended particulate sediment, Semienclosed bay |
Databáze: | OpenAIRE |
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