基于3年的野外调查数据，运用平行因子法(PARAFAC)解析三维荧光光谱(EEMs)，对三峡库区（百岁溪、九畹溪、沙镇溪和神农溪）水体中溶解有机物(CDOM)的垂直分布特征及来源进行了分析。结果表明：三峡库区POC和DOC含量具有相似的垂直分布特征，百岁溪、九畹溪、沙镇溪和神农溪POC和DOC含量随水深的增加而逐渐降低，其中表层最大，表层以下急剧降低，3 m以下降低趋势区域缓和，10 m处POC和DOC含量基本相等。其中相同水深基本表现为：百岁溪>九畹溪>沙镇溪>神农溪，局部有所波动。三峡库区营养盐垂直分布特征较为一致，其中百岁溪、九畹溪、沙镇溪和神农溪TP、TN、NH+4和NO-3含量随水深的增加而逐渐降低，其中表层最大，表层以下急剧降低，3 m以下降低趋势区域缓和，10 m处TP、TN、NH+4和NO-3含量基本相等。其中相同水深基本表现为：百岁溪>九畹溪>沙镇溪>神农溪，局部有所波动。三峡库区水质较好，总体为Ⅱ~Ⅲ类，其中TLI指数依次表现为百岁溪>九畹溪>沙镇溪>神农溪，百岁溪属于富营养级，主要是由于N含量超标，九畹溪、沙镇溪属于中营养级，神农溪属于轻度富营养。综合营养状态指数均值为35，属于中营养水平。百岁溪、九畹溪、沙镇溪、神农溪CDOM吸收系数a(280)和a(350)均表现为百岁溪<九畹溪<沙镇溪<神农溪。回归分析显示：百岁溪和沙镇溪POC和DOC与CDOM吸收系数a(280)呈显著线性相关（p<0.01）；九畹溪和神农溪POC和DOC与CDOM吸收系数a(350)呈显著线性相关（p<0.01）。三峡库区荧光指数(FI)在1.32~1.43之间，均值为1.39，说明三峡库区陆源占主要贡献。生物指数(BIX)在1.03~1.14之间，说明三峡库区CDOM主要由生物细菌活动产生。腐殖化指数(HIX)在1.62~1.97之间，说明三峡库区CDOM主要由生物细菌活动产生，与BIX指数一致。由此说明三峡库区CDOM来源于自生微生物、藻类等新近自生源。
Abstract
Based on 3-year field survey data, three dimensional fluorescence spectra (EEMs) are analyzed by PARAFAC, and the vertical distribution characteristics and source of CDOM in three gorges reservoir area (baishuixi, jiuwanxi, shazhunxi and shennongxi) are analyzed.Results show that the three gorges reservoir area of DOC and POC content with similar characteristics of vertical distribution of 0 to 10 m centenarians creek, drifting at jiuwanxi, sand town creek and shennong xi DOC and POC content gradually decreased with the increase of the depth of the water, the surface layer, the largest surface sharply reduce, reduce trend area below the 3 m, 10 m of DOC and POC content basic equal.The same water depth is basically expressed as follows: 100 years old stream > nine wan stream > sand town stream > shennong stream, local fluctuations.Nutrient vertical distribution characteristics of the three gorges reservoir is relatively consistent, with 0 to 10 m centenarians creek, drifting at jiuwanxi, sand town creek and shennong xi TP, TN, NH4+ and NO3- content gradually decreased with the increase of the depth of the water, the surface layer, the largest surface sharply reduce, reduce trend area below the 3 m, 10 m in TP, TN, NH4 + and NO3 - content basic equal.The same water depth is basically expressed as follows: baisui stream > jiuwan stream > sand town stream > shennong stream, local fluctuations.The three gorges reservoir area water quality is better, overall Ⅱ - Ⅲ classes, including TLI index in performance for drifting at baisui stream > jiuwan stream > sand town stream > shennong stream, centenarians creek to eutrophication level, mainly because of the excessive concentration of N, drifting at jiuwanxi, belongs to the trophic level in the sand town creek, shennong xi belong to light eutrophication.The mean value of the comprehensive nutrition status index was 35, belonging to medium nutrition level.The CDOM absorption coefficient a(280) and a(350) of baisui stream, jiuwan stream, shazhen stream and shennong stream are all expressed as baisui stream < jiuwan stream < shazhen stream < shennong stream.Regression analysis showed that POC and DOC of baishuixi and shazzhenxi had significant linear correlation with CDOM absorption coefficient a(280) (p<0.01).Nine wanxi and shennongxi POC and DOC have significant linear correlation with CDOM absorption coefficient a(350) (p<0.01).The fluorescence index (FI) of the three gorges reservoir area ranged from 1.32 to 1.43, with an average value of 1.39, indicating that terrestrial sources accounted for the major contribution in the three gorges reservoir area.Biological index (BIX) was between 1.03 and 1.14, indicating that CDOM in the three gorges reservoir area was mainly generated by biological and bacterial activities.The humification index (HIX) was between 1.62 and 1.97, indicating that the CDOM in the three gorges reservoir area was mainly generated by biological and bacterial activities, which was consistent with the BIX index.This indicates that the CDOM in the three gorges reservoir area is derived from autogenous microorganisms, algae and other recent autogenous sources.
关键词
三峡库区 /
溶解性有机物 /
颗粒物 /
垂直分布
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Key words
waters Three Gorges Reservoir /
dissolved organic matter /
particulate matter /
vertical variation /
sources
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参考文献
[1]KELLERMAN A M, KOTHAWALA D N, DITTMAR T, et al. Persistence of dissolved organic matter in lakes related to its molecular characteristics[J]. Nature Geoscience, 2015,8(6):454.
[2]RAYMOND P A, SAIERS J E, SOBCZAK W V. Hydrological and biogeochemical controls on watershed dissolved organic matter transport: Pulse‐shunt concept[J]. Ecology, 2016,97(1):5-16.
[3]HANSEN A M, KRAUS T E C, PELLERIN B A, et al. Optical properties of dissolved organic matter (DOM): Effects of biological and photolytic degradation[J]. Limnology and Oceanography, 2016,61(3):1 015-1 032.
[4]REPETA D J, FERRON S, SOSA O A, et al. Marine methane paradox explained by bacterial degradation of dissolved organic matter[J]. Nature Geoscience, 2016,9(12):884.
[5]LOGUE J B, STEDMON C A, KELLERMAN A M, et al. Experimental insights into the importance of aquatic bacterial community composition to the degradation of dissolved organic matter[J]. The ISME journal, 2016,10(3):533.
[6]SMEBYE A, ALLING V, VOGT R D, et al. Biochar amendment to soil changes dissolved organic matter content and composition[J]. Chemosphere, 2016,142:100-105.
[7]MCNEILL K, CANONICA S. Triplet state dissolved organic matter in aquatic photochemistry: reaction mechanisms, substrate scope, and photophysical properties[J]. Environmental Science: Processes & Impacts, 2016,18(11):1 381-1 399.
[8]SOLOMON C T, JONES S E, WEIDEL B C, et al. Ecosystem consequences of changing inputs of terrestrial dissolved organic matter to lakes: current knowledge and future challenges[J]. Ecosystems, 2015,18(3):376-389.
[9]WUNSCH U J, MURPHY K R, STEDMON C A. The one-sample PARAFAC approach reveals molecular size distributions of fluorescent components in dissolved organic matter[J]. Environmental science & technology, 2017,51(20):11 900-11 908.
[10]ROSARIO-ORTIZ F L, CANONICA S. Probe compounds to assess the photochemical activity of dissolved organic matter[J]. Environmental science & technology, 2016,50(23):12 532-12 547.
[11]MATSUOKA A, BOSS E, BABIN M, et al. Pan-Arctic optical characteristics of colored dissolved organic matter: Tracing dissolved organic carbon in changing Arctic waters using satellite ocean color data[J]. Remote Sensing of Environment, 2017,200:89-101.
[12]ROSARIO-ORTIZ F L, CANONICA S. Probe compounds to assess the photochemical activity of dissolved organic matter[J]. Environmental science & technology, 2016,50(23):12 532-12 547.
[13]SHEN Y, CHAPELLE F H, STROM E W, et al. Origins and bioavailability of dissolved organic matter in groundwater[J]. Biogeochemistry, 2015,122(1):61-78.
[14]CREED I F, MCKNIGHT D M, PELLERIN B A, et al. The river as a chemostat: fresh perspectives on dissolved organic matter flowing down the river continuum[J]. Canadian Journal of Fisheries and Aquatic Sciences, 2015,72(8):1 272-1 285.
[15]CHEN W, HABIBUL N, LIU X Y, et al. FTIR and synchronous fluorescence heterospectral two-dimensional correlation analyses on the binding characteristics of copper onto dissolved organic matter[J]. Environmental science & technology, 2015,49(4):2 052-2 058.
[16]FASCHING C, ULSETH A J, SCHELKER J, et al. Hydrology controls dissolved organic matter export and composition in an Alpine stream and its hyporheic zone[J]. Limnology and oceanography, 2016,61(2): 558-571.
[17]WILLAMS C J, FROST P C, MORALES‐WILLIAMS A M, et al. Human activities cause distinct dissolved organic matter composition across freshwater ecosystems[J]. Global change biology, 2016,22(2):613-626.
[18]OSTERHOLZ H, NIGGEMANN J, GIEBEL H A, et al. Inefficient microbial production of refractory dissolved organic matter in the ocean[J]. Nature communications, 2015,6:7 422.
[19]施周, 闫杭召, 毕晨, 等. 基于地统计学克里格插值法的村镇地表水体水质监测[J]. 环境工程学报, 2017(4):2 607-2 613.
[20]李冰, 杨桂山, 万荣荣, 等. 鄱阳湖出流水质 2004~ 2014 年变化及其对水位变化的响应: 对水质监测频率的启示[J]. 长江流域资源与环境, 2017,26(2):289-296.
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