کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1261234 1496667 2015 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Distribution, mixing behavior, and transformation of dissolved inorganic phosphorus and suspended particulate phosphorus along a salinity gradient in the Changjiang Estuary
ترجمه فارسی عنوان
توزیع، رفتار مخلوط کردن و تبدیل فسفر غیر معدنی محلول و ذرات معلق فسفر در امتداد شیب شوری در رودخانه چانگ لیانگ
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی (عمومی)
چکیده انگلیسی


• Distribution, mixing behavior and transformation of P species in the Changjiang Estuary
• Role of fine particles in bioavailability/transport of P
• Loss of labile P during particle settlement

Surface water and suspended particulate matter (SPM) samples were collected along a salinity gradient in the Changjiang Estuary in June, 2011 to examine the distribution, mixing behavior and transformation of dissolved and particulate phosphorus (P) species. Particulate P was fractionated into five size fractions using a water elutriation method, followed by a sequential extraction procedure (SEDEX). Dissolved inorganic P (DIP) concentrations ranged from 0.53 to 3.02 μmol L− 1 with a mean of 1.44 μmol L− 1, while total particulate P (TPP) concentrations ranged from 20.56 to 26.90 μmol L− 1 (24.21 μmol L− 1). The variation of DIP and P species in both bulk and size fractionated particles along the salinity gradient indicated a significant transformation between different P phases, especially for labile P such as exchangeable P (Ex-P), organic P (Or-P) and Fe-bound P (Fe-P) in a particulate P pool. Among all P forms, detrital P (De-P) and Or-P in SPM were the most abundant, accounting for 43.9% and 26.1% of TPP in bulk particles. De-P increased with increasing particle grain size, with an average concentration of 8.92 ± 2.20 μmol g− 1 in the clay fraction (< 8 μm) and 12.6 ± 1.49 μmol g− 1 in the sand fraction (> 63 μm), whereas Or-P and other P forms decreased gradually with increasing grain size. The average concentration of Or-P in clay fraction was 6.93 ± 1.92 μmol g− 1 and it decreased to 1.59 ± 0.61 μmol g− 1 in the sand fraction. The flux of bioavailable P (BAP, sum of Ex-P, Or-P and Fe-P) in clay fraction (< 8 μm), defined as “truly” suspended particles, was estimated to be 0.21 × 104 t P yr− 1 and accounted for 29% of the bulk BAP flux. The particulate P to specific surface area ratios (P/SSA) was lower in fine suspended particles than in coarse particles, indicating lower preservation of P in these particles. When compared with the bed sediments of the Changjiang Estuary, the P/SSA loadings in fractionated suspended particles were maintained at the same level for De-P and Fe-P, slightly higher for authigenic P (Au-P) and refractory P (Re-P) and obviously higher for labile P such as Ex-P and Or-P, further indicating the differential behavior of P forms during particle settlement in this dynamic estuary.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Marine Chemistry - Volume 168, 20 January 2015, Pages 124–134
نویسندگان
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