1
|
Zapitis C, Ramsey A, Huck M, Landler L, Burian A. 'Phototaxis' in the absence of light? Locomotory patterns in unionid mussels. J Exp Biol 2023; 226:jeb245159. [PMID: 37732510 DOI: 10.1242/jeb.245159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 08/14/2023] [Indexed: 09/22/2023]
Abstract
Locomotion in benthic invertebrates can strongly affect habitat selection and ecosystem nutrient cycling. In the case of freshwater mussels, the drivers of locomotion are largely unresolved. Our aim was to assess the influence of light presence and intensity on the locomotory behaviour of freshwater mussels in controlled laboratory experiments. The species investigated in our study were Anodonta anatina and Unio pictorum, two widely distributed mussels in European lentic and lotic inland waters. At low algal concentrations, known to be associated with more frequent locomotory activities, we found that both species moved primarily in the absence of light (72.7% of all movements across experiments). However, the movements of both species were directed towards the light source, resembling a net-positive 'phototactic' response but in the absence of light. The distance to the light source, which was negatively correlated to light intensity, had a positive effect on the distance covered in locomotory activities by A. anatina but not by U. pictorum. Intraspecific variation in shell size had no impact on movement distance, indicating that the energetic costs of movement were not a limiting factor. We suggest that the observed movement towards brighter locations helps to enhance food quantity and quality, whilst movement in darkness mitigates predation risks.
Collapse
Affiliation(s)
- Charitos Zapitis
- College of Science and Engineering, School of Built and Natural Environment , University of Derby, Derby, DE22 1GB, UK
- Science Directorate, Natural England, York, YO1 7PX, UK
| | - Andrew Ramsey
- College of Science and Engineering, School of Built and Natural Environment , University of Derby, Derby, DE22 1GB, UK
| | - Maren Huck
- College of Science and Engineering, School of Built and Natural Environment , University of Derby, Derby, DE22 1GB, UK
| | - Lukas Landler
- Institute of Zoology , University of Natural Resources and Life Sciences (BOKU), 1180 Vienna, Austria
| | - Alfred Burian
- Department of Computational Landscape Ecology, UFZ- Helmholtz Centre for Environmental Research, 04318 Leipzig, Germany
- Marine Ecology Department, Lúrio University, 3202 Pemba, Mozambique
| |
Collapse
|
2
|
Shao T, Liang X, Zhuang D, Zheng K, Wang T. Seasonal variations in CDOM characteristics and effects of environmental factors in coastal rivers, Northeast China. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:29052-29064. [PMID: 36401691 DOI: 10.1007/s11356-022-24165-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 11/08/2022] [Indexed: 06/16/2023]
Abstract
Colored dissolved organic matter (CDOM) is highly spatiotemporally varied due to the effects of complex environmental factors within a catchment or system. The seasonal nutritional status and potential risks of heavy metals in the coastal rivers of the Liaohe River basin were evaluated based on 40 water samples in January, April, May, and September. Meanwhile, the effects of environmental factors on CDOM, especially human activities, were quantitatively analyzed. The trophic state index (TSI) and the potential ecological risk index (RI) of heavy metals in the Liaohe River basin exhibited significant differences. The rivers were mesotrophic in January, lightly eutrophic in May, and highly eutrophic in April and September. An extremely high RI was shown in April and May, while a high RI was exhibited in September. CDOM exhibited great seasonal characteristics and showed significant seasonal correlations with environmental factors. Based on multiple general linear model analysis, total phosphorus (TP) was the most influential factor and significantly explained 62.1% of aCDOM(440) (p < 0.01) among the water parameters, followed by total alkalinity (38.3%). The percentages of built-up area exerted significantly positive effects on aCDOM(440) (R2 = 0.44), while distance from oil extraction sites significantly negatively affected aCDOM(440) (r = - 0.328, p < 0.05). Polluting enterprises showed non-significant correlation with CDOM (r = 0.314, p = 0.178).
Collapse
Affiliation(s)
- Tiantian Shao
- Key Research Institute of Yellow River Civilization and Sustainable Development & Collaborative Innovation Center On Yellow River Civilization, Henan University, Kaifeng, 475001, China
| | - Xiaowen Liang
- Key Research Institute of Yellow River Civilization and Sustainable Development & Collaborative Innovation Center On Yellow River Civilization, Henan University, Kaifeng, 475001, China
| | - Danyuan Zhuang
- Key Research Institute of Yellow River Civilization and Sustainable Development & Collaborative Innovation Center On Yellow River Civilization, Henan University, Kaifeng, 475001, China
| | - Ke Zheng
- School of Computer and Information Engineering, Henan University, Kaifeng, 475004, China
- , Kaifeng, China
| | - Tao Wang
- Key Research Institute of Yellow River Civilization and Sustainable Development & Collaborative Innovation Center On Yellow River Civilization, Henan University, Kaifeng, 475001, China
| |
Collapse
|
3
|
Li J, Li Y, Liu M, Yu Z, Song D, Jeppesen E, Zhou Q. Patterns of thermocline structure and the deep chlorophyll maximum feature in multiple stratified lakes related to environmental drivers. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 851:158431. [PMID: 36055493 DOI: 10.1016/j.scitotenv.2022.158431] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 08/23/2022] [Accepted: 08/27/2022] [Indexed: 06/15/2023]
Abstract
Thermal stratification and the deep chlorophyll maximum (DCM), two commonly related phenomena in stratified lakes, play fundamental roles in eco-environmental processes. However, the progressive linkages among multi-dimensional environmental factors, thermal stratification and DCM were poorly explored, which greatly constrains our understanding of cross-level governance in deep lakes. In this study, the thermocline structure (i.e., thermocline depth, thickness and strength) and DCM feature (depth and thickness) and their driving factors were investigated at regional scale using data from 18 stratified lakes differing in limnological characteristics, Southwest China. Our study showed that (1) DCM occurred close to the thermocline in most lakes (represented by their depth and thickness), (2) the depths of the thermocline and DCM were both shallower than the euphotic depth, and (3) spatial heterogeneity occurred the thermocline structure and the DCM feature, reflecting different environmental factors. Specifically, water depth and light penetration depths were both positively correlated with thermocline depth and thickness and the DCM feature, and ultraviolet radiation (UVR) was more important than photosynthetically active radiation (PAR) for thermocline depth, but PAR was more important for thermocline thickness; moreover, PAR played a more prominent role than UVR for the DCM feature. As there were interactions between some environmental factors, we built a cascading path using a partial least squares path modelling for the DCM feature: lake morphometry directly impacted the thermocline structure and surface water quality; the water quality further affected light penetration depths as well as the thermocline structure; light penetration depth and thermocline structure combined directly determined the DCM feature, where the importance of light was larger. Our findings provide information on the cascading drivers of the thermocline structure and DCM feature in deep lakes and also constitute a valuable reference for deep lake management under the dual pressure of climate change and eutrophication.
Collapse
Affiliation(s)
- Jingyi Li
- Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Sciences, Yunnan University, Kunming 650500, China
| | - Yuanrui Li
- Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Sciences, Yunnan University, Kunming 650500, China
| | - Miao Liu
- Jiangsu Provincial Academy of Environmental Science, Nanjing 210098, China
| | - Zhirong Yu
- Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Sciences, Yunnan University, Kunming 650500, China
| | - Di Song
- Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed, Yunnan Research Academy of Eco-environmental Sciences, Kunming 650034, China
| | - Erik Jeppesen
- Department of Ecoscience and Arctic Research Centre, Aarhus University, Aarhus 8000, Denmark; Sino-Danish Centre for Education and Research, Chinese Academy of Sciences, Beijing 100101, China; Limnology Laboratory, Department of Biological Sciences and Centre for Ecosystem Research and Implementation, Middle East Technical University, Ankara 06800, Turkey; Institute of Marine Sciences, Middle East Technical University, Erdemli-Mersin 33731, Turkey
| | - Qichao Zhou
- Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Sciences, Yunnan University, Kunming 650500, China; Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed, Yunnan Research Academy of Eco-environmental Sciences, Kunming 650034, China.
| |
Collapse
|
4
|
Cao Q, Yu G, Qiao Z. Application and recent progress of inland water monitoring using remote sensing techniques. ENVIRONMENTAL MONITORING AND ASSESSMENT 2022; 195:125. [PMID: 36401670 DOI: 10.1007/s10661-022-10690-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 10/19/2022] [Indexed: 06/16/2023]
Abstract
Hyperspectral remote sensing, which retrieves the water quality parameters by direct high-resolution analysis of the electromagnetic spectrum reflected from the water surface, has been widely applied for inland water quality detection. Such a new approach provides an opportunity to generate real-time data from water with the noncontact method, largely improving working efficiency. By summarizing the development and current applications of hyperspectral remote sensing, we compare the relative merits of varying remote sensing platforms, popular inversion models, and the application of hyperspectral monitoring of chlorophyll-a (Chl-a), transparency, total suspended solids (TSS), colored dissolved organic matter (CDOM), phycocyanin (PC), total phosphorus (TP), and total nitrogen (TN) water quality parameters. Most studies have focused on spaceborne remote sensing, which is usually used to monitor large waterbodies for Chl-a and other water quality parameters with optical properties; semiempirical, bio-optical, and semianalytical models are frequently used. With the rapid development of aerospace technology and near-surface remote sensing, the spectral resolution of remote sensing imaging technology has been dramatically improved and has begun to be applied to small waterbodies. In the future, the multiplatform linkage monitoring approach may become a new research direction. Advanced computer technology has also enabled machine learning models to be applied to water quality parameter inversion, and machine learning models have higher robustness than the three commonly used models mentioned above. Although nitrogen and phosphorus, with nonoptical properties, have also received attention and research from some scholars in recent years, the uncertainty of their mechanisms makes it necessary to maintain a cautious attitude when treating such research.
Collapse
Affiliation(s)
- Qi Cao
- Tianjin Key Laboratory of Aqua-Ecology and Aquaculture, College of Fisheries, Tianjin Agricultural University, Tianjin, 300384, China
| | - Gongliang Yu
- CAS Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Zhiyi Qiao
- Tianjin Key Laboratory of Aqua-Ecology and Aquaculture, College of Fisheries, Tianjin Agricultural University, Tianjin, 300384, China.
| |
Collapse
|
5
|
Zhang M, Zhang Y, Zhou Y, Zhang Y, Shi K, Jiang C. Influence of cyanobacterial bloom accumulation and dissipation on underwater light attenuation in a large and shallow lake. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:79082-79094. [PMID: 35701699 DOI: 10.1007/s11356-022-21384-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 06/06/2022] [Indexed: 06/15/2023]
Abstract
Cyanobacterial bloom accumulation and dissipation frequently occur in Lake Taihu, a typically shallow, eutrophic lake due to wind wave disturbance. However, knowledge of the driving mechanisms of cyanobacterial blooms on underwater light attenuation is still limited. In this study, we collected a high-frequency in situ monitoring of the wind field, underwater light environment, and surface water quality to elucidate how cyanobacterial bloom accumulation and dissipation affect the variations in underwater light attenuation in the littoral zone of Lake Taihu. Results showed that cyanobacterial blooms significantly increased the diffuse attenuation coefficient of ultraviolet-B (Kd(313)), ultraviolet-A (Kd(340)), and photosynthetically active radiation (Kd(PAR)); the scattering of total suspended matter (bbp(λ)); and the absorption of phytoplankton (aph(λ)) and chromophoric dissolved organic matter (CDOM, ag(λ)) (p < 0.01). The Kd(PAR) decreased quickly during the processes of bloom dissipation, but the decrease of Kd(313) and Kd(340) lagged 0.5 day. Our results suggested that cyanobacterial blooms could increase particle matters and elevated the production of autochthonous CDOM, resulting in underwater light attenuation increase. Ultraviolet radiation (UVR) and PAR attenuation both have significant responses to cyanobacterial blooms, but the response processes were distinct due to the different changes of particle and dissolved organic matters. Our study unravels the driving mechanisms of cyanobacterial blooms on underwater light attenuation, improving lake ecosystem management and protection.
Collapse
Affiliation(s)
- Manxue Zhang
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China
- College of Water Resources and Hydrology, Hohai University, Nanjing, 210098, China
| | - Yunlin Zhang
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Yongqiang Zhou
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yibo Zhang
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Kun Shi
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Cuiling Jiang
- College of Water Resources and Hydrology, Hohai University, Nanjing, 210098, China
| |
Collapse
|
6
|
Ren L, Huang J, Ding K, Wang Y, Yang Y, Zhang L, Wu H. Comparative Study of Algal Responses and Adaptation Capability to Ultraviolet Radiation with Different Nutrient Regimes. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19095485. [PMID: 35564879 PMCID: PMC9104955 DOI: 10.3390/ijerph19095485] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 04/24/2022] [Accepted: 04/28/2022] [Indexed: 02/04/2023]
Abstract
Frequent outbreaks of harmful algal blooms (HABs) represent one of the most serious outcomes of eutrophication, and light radiation plays a critical role in the succession of species. Therefore, a better understanding of the impact of light radiation is essential for mitigating HABs. In this study, Chlorella pyrenoidosa and non-toxic and toxic Microcystis aeruginosa were mono-cultured and co-cultured to explore algal responses under different nutrient regimes. Comparisons were made according to photosynthetically active radiation (PAR), UV-B radiation exerted oxidative stresses, and negative effects on the photosynthesis and growth of three species under normal growth conditions, and algal adaptive responses included extracellular polymeric substance (EPS) production, the regulation of superoxide dismutase (SOD) activity, photosynthetic pigments synthesis, etc. Three species had strain-specific responses to UV-B radiation and toxic M. aeruginosa was more tolerant and showed a higher adaptation capability to UV-B in the mono-cultures, including the lower sensitivity and better self-repair efficiency. In addition to stable μmax in PAR ad UV-B treatments, higher EPS production and enhanced production of photosynthetic pigments under UV-B radiation, toxic M. aeruginosa showed a better recovery of its photosynthetic efficiency. Nutrient enrichment alleviated the negative effects of UV-B radiation on three species, and the growth of toxic M. aeruginosa was comparable between PAR and UV-B treatment. In the co-cultures with nutrient enrichment, M. aeruginosa gradually outcompeted C. pyrenoidosa in the PAR treatment and UV-B treatment enhanced the growth advantages of M. aeruginosa, when toxic M. aeruginosa showed a greater competitiveness. Overall, our study indicated the adaptation of typical algal species to ambient UV-B radiation and the stronger competitive ability of toxic M. aeruginosa in the UV-radiated waters with severer eutrophication.
Collapse
Affiliation(s)
- Lingxiao Ren
- School of Environmental Engineering, Nanjing Institute of Technology, Nanjing 211167, China; (K.D.); (Y.W.); (L.Z.); (H.W.)
- Correspondence: ; Tel.: +86-158-5066-2170
| | - Jing Huang
- Three Gorges Beijing Enterprises Nanjing Water Group Co., Ltd., Nanjing 210000, China;
| | - Keqiang Ding
- School of Environmental Engineering, Nanjing Institute of Technology, Nanjing 211167, China; (K.D.); (Y.W.); (L.Z.); (H.W.)
| | - Yi Wang
- School of Environmental Engineering, Nanjing Institute of Technology, Nanjing 211167, China; (K.D.); (Y.W.); (L.Z.); (H.W.)
| | - Yangyang Yang
- School of Environmental Engineering, Xuzhou University of Technology, Xuzhou 221018, China;
| | - Lijuan Zhang
- School of Environmental Engineering, Nanjing Institute of Technology, Nanjing 211167, China; (K.D.); (Y.W.); (L.Z.); (H.W.)
| | - Haoyu Wu
- School of Environmental Engineering, Nanjing Institute of Technology, Nanjing 211167, China; (K.D.); (Y.W.); (L.Z.); (H.W.)
| |
Collapse
|
7
|
Li D, Pan B, Han X, Li J, Zhu Q, Li M. Assessing the potential to use CDOM as an indicator of water quality for the sediment-laden Yellow river, China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 289:117970. [PMID: 34426192 DOI: 10.1016/j.envpol.2021.117970] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 08/09/2021] [Accepted: 08/12/2021] [Indexed: 06/13/2023]
Abstract
Chromophoric dissolved organic matter (CDOM) in rivers is mainly affected by natural conditions and human activities and can reflect the watershed pollution status to a certain extent. The Yellow River is one of the largest contributors to the global riverine sediment flux from the land to ocean, and there is a paucity of information on how the optical properties of CDOM have the potential to serve as an indicator of water quality for the sediment-laden Yellow River. In this study, a three-dimensional fluorescence parallel factor (PARAFAC) analysis method was applied to investigate the seasonal and spatial variations in CDOM fluorescence components and spectral characteristics from the source region to the estuary in the mainstream of Yellow River. The relationships of CDOM with water quality indicators and trophic state were also analyzed. Six PARAFAC components (C1-C6) were identified and grouped into two categories: humic-like components (C1-C4), which accounted for 85.8 %, and protein-like components (C5 and C6), which accounted for only 14.2 %. The CDOM components, spectral parameters, and their clear correlations with the main ions (Na+ and Cl-) all indicated that the humic-like components may be primarily derived from nonpoint source erosion, and the protein-like components were mainly derived from point source discharges in the watershed. The combination of the CDOM absorption coefficient at 254 nm (a(254)), spectral slope ratio (SR), specific UV absorbance SUVA254, and fluorescence index (FI) had a good predictive ability for the key water quality indicators (total nitrogen (TN), dissolved total nitrogen (DTN), total phosphorus (TP), dissolved total phosphorus (DTP), and chlorophyll a (Chl a)) and trophic state index (TSI). Therefore, some fluorophores and UV spectral parameters of CDOM in the Yellow River can be used for rapid water quality monitoring and pollution source indication, especially pollutants related to nitrogen and phosphorus nutrients in the basin.
Collapse
Affiliation(s)
- Dianbao Li
- State Key Laboratory of Eco-hydraulic in Northwest Arid Region of China, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China
| | - Baozhu Pan
- State Key Laboratory of Eco-hydraulic in Northwest Arid Region of China, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China.
| | - Xu Han
- State Key Laboratory of Eco-hydraulic in Northwest Arid Region of China, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China
| | - Junhua Li
- Yellow River Institute of Hydraulic Research, Zhengzhou, 450003, China
| | - Qingwei Zhu
- State Key Laboratory of Eco-hydraulic in Northwest Arid Region of China, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China
| | - Ming Li
- College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, China
| |
Collapse
|
8
|
Shang Y, Jacinthe PA, Li L, Wen Z, Liu G, Lyu L, Fang C, Zhang B, Hou J, Song K. Variations in the light absorption coefficients of phytoplankton, non-algal particles and dissolved organic matter in reservoirs across China. ENVIRONMENTAL RESEARCH 2021; 201:111579. [PMID: 34197817 DOI: 10.1016/j.envres.2021.111579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 05/06/2021] [Accepted: 06/20/2021] [Indexed: 06/13/2023]
Abstract
Reservoirs were critical sources of drinking water for many large cities around the world, but progress in the development of large-scale monitoring protocols to obtain timely information about water quality had been hampered by the complex nature of inland waters and the various optical conditions exhibited by these aquatic ecosystems. In this study, we systematically investigated the absorption coefficient of different optically-active constituents (OACs) in 120 reservoirs of different trophic states across five eco-regions in China. The relationships were found between phytoplankton absorption coefficient at 675 nm (aph (675)) and Chlorophyll a (Chla) concentration in different regions (R2:0.60-0.82). The non-algal particle (NAP) absorption coefficient (aNAP) showed an increasing trend for reservoirs with trophic states. Significant correlation (p < 0.05) was observed between chromophoric dissolved organic matter (CDOM) absorption and water chemical parameters. The influencing factors for contributing the relative proportion of OACs absorption including the hydrological factors and water quality factors were analyzed. The non-water absorption budget from our data showed the variations of the dominant absorption types which underscored the need to develop and parameterize region-specific bio-optical models for large-scale assessment in water reservoirs.
Collapse
Affiliation(s)
- Yingxin Shang
- Northeast Institute of Geography and Agroecology, CAS, Changchun, 130102, Jilin, China; Changchun Jingyuetan Remote Sensing Observation Station, Chinese Academy of Sciences, Changchun, 130102, China; University of Chinese Academy of Science, Beijing, 100049, China
| | - Pierre-Andre Jacinthe
- Department of Earth Sciences, Indiana University-Purdue University, Indianapolis, IN, USA
| | - Lin Li
- Department of Earth Sciences, Indiana University-Purdue University, Indianapolis, IN, USA
| | - Zhidan Wen
- Northeast Institute of Geography and Agroecology, CAS, Changchun, 130102, Jilin, China; Changchun Jingyuetan Remote Sensing Observation Station, Chinese Academy of Sciences, Changchun, 130102, China
| | - Ge Liu
- Northeast Institute of Geography and Agroecology, CAS, Changchun, 130102, Jilin, China; Changchun Jingyuetan Remote Sensing Observation Station, Chinese Academy of Sciences, Changchun, 130102, China
| | - Lili Lyu
- Northeast Institute of Geography and Agroecology, CAS, Changchun, 130102, Jilin, China; University of Chinese Academy of Science, Beijing, 100049, China
| | - Chong Fang
- Northeast Institute of Geography and Agroecology, CAS, Changchun, 130102, Jilin, China; University of Chinese Academy of Science, Beijing, 100049, China
| | - Bai Zhang
- Northeast Institute of Geography and Agroecology, CAS, Changchun, 130102, Jilin, China; Changchun Jingyuetan Remote Sensing Observation Station, Chinese Academy of Sciences, Changchun, 130102, China
| | - Junbin Hou
- Northeast Institute of Geography and Agroecology, CAS, Changchun, 130102, Jilin, China
| | - Kaishan Song
- Northeast Institute of Geography and Agroecology, CAS, Changchun, 130102, Jilin, China; Changchun Jingyuetan Remote Sensing Observation Station, Chinese Academy of Sciences, Changchun, 130102, China; School of Environment and Planning, Liaocheng University, Liaocheng, 252000, China.
| |
Collapse
|
9
|
Machine Learning Algorithms for Chromophoric Dissolved Organic Matter (CDOM) Estimation Based on Landsat 8 Images. REMOTE SENSING 2021. [DOI: 10.3390/rs13183560] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Chromophoric dissolved organic matter (CDOM) is crucial in the biogeochemical cycle and carbon cycle of aquatic environments. However, in inland waters, remotely sensed estimates of CDOM remain challenging due to the low optical signal of CDOM and complex optical conditions. Therefore, developing efficient, practical and robust models to estimate CDOM absorption coefficient in inland waters is essential for successful water environment monitoring and management. We examined and improved different machine learning algorithms using extensive CDOM measurements and Landsat 8 images covering different trophic states to develop the robust CDOM estimation model. The algorithms were evaluated via 111 Landsat 8 images and 1708 field measurements covering CDOM light absorption coefficient a(254) from 2.64 to 34.04 m−1. Overall, the four machine learning algorithms achieved more than 70% accuracy for CDOM absorption coefficient estimation. Based on model training, validation and the application on Landsat 8 OLI images, we found that the Gaussian process regression (GPR) had higher stability and estimation accuracy (R2 = 0.74, mean relative error (MRE) = 22.2%) than the other models. The estimation accuracy and MRE were R2 = 0.75 and MRE = 22.5% for backpropagation (BP) neural network, R2 = 0.71 and MRE = 24.4% for random forest regression (RFR) and R2 = 0.71 and MRE = 24.4% for support vector regression (SVR). In contrast, the best three empirical models had estimation accuracies of R2 less than 0.56. The model accuracies applied to Landsat images of Lake Qiandaohu (oligo-mesotrophic state) were better than those of Lake Taihu (eutrophic state) because of the more complex optical conditions in eutrophic lakes. Therefore, machine learning algorithms have great potential for CDOM monitoring in inland waters based on large datasets. Our study demonstrates that machine learning algorithms are available to map CDOM spatial-temporal patterns in inland waters.
Collapse
|
10
|
Zhang Y, Li K, Zhou Q, Chen L, Yang X, Zhang H. Phytoplankton responses to solar UVR and its combination with nutrient enrichment in a plateau oligotrophic Lake Fuxian: a mesocosm experiment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:29931-29944. [PMID: 33576963 DOI: 10.1007/s11356-021-12705-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 01/25/2021] [Indexed: 05/20/2023]
Abstract
Multiple stressors associated with global change are influencing the phytoplankton taxonomic composition and biomass in plateau lakes, such as higher levels of ultraviolet radiation (UVR, 280-400 nm) and the risk of eutrophication. Although the restrictive effects of high UVR on phytoplankton are generally recognized, the effects will be impacted by the UVR levels of seasonal changes and the nutrient status. In this study, in situ phytoplankton productivity was measured seasonally under full solar radiation and only visible light (photosynthetically active radiation, PAR) conditions in the plateau oligotrophic Lake Fuxian, Southwest China. To determine the single effects of UVR and nutrient enrichment and their combined impact on phytoplankton communities, a mesocosm experiment (1 month) was conducted outdoors during late summer (rainy season). The interactive experiment was designed with two radiation treatments (UVR + PAR and PAR) and four nutrient treatments (raw water, nitrogen addition, phosphorus addition, nitrogen and phosphorus addition). Our results suggested that the response of phytoplankton to UVR depended largely on nutrient availability, which was embodied in the no significant responses of phytoplankton productivity and total biomass to UVR in the oligotrophic raw water from Lake Fuxian, but the positive responses of total biomass to UVR in the nutrient enrichment treatment. Furthermore, the response of phytoplankton to UVR was also taxa dependent. Chlorophytes and dinoflagellates showed positive response to UVR, whereas chrysophytes were quite sensitive to UVR; diatoms had no significant response to UVR under all nutrient conditions, while the response of cyanobacteria to UVR was highly dependent on nutrient status. This study highlights that the increase in nutrient concentrations in oligotrophic lake not only directly promotes the growth of phytoplankton but also combines with low UVR during summer to benefit the growth of eutrophic taxa based on the non-negative effect of UVR on total phytoplankton biomass and the positive effect on eutrophic taxa.
Collapse
Affiliation(s)
- Yun Zhang
- Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Sciences, Yunnan University, Kunming, 650500, China
| | - Kaidi Li
- Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Sciences, Yunnan University, Kunming, 650500, China
- Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed, Yunnan Research Academy of Eco-environmental Sciences, Kunming, 650034, China
| | - Qichao Zhou
- Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Sciences, Yunnan University, Kunming, 650500, China.
- Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed, Yunnan Research Academy of Eco-environmental Sciences, Kunming, 650034, China.
| | - Le Chen
- Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Sciences, Yunnan University, Kunming, 650500, China
- Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed, Yunnan Research Academy of Eco-environmental Sciences, Kunming, 650034, China
| | - Xuan Yang
- Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Sciences, Yunnan University, Kunming, 650500, China
| | - Hucai Zhang
- Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Sciences, Yunnan University, Kunming, 650500, China.
| |
Collapse
|
11
|
Zhang Y, Zhou L, Zhou Y, Zhang L, Yao X, Shi K, Jeppesen E, Yu Q, Zhu W. Chromophoric dissolved organic matter in inland waters: Present knowledge and future challenges. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 759:143550. [PMID: 33246724 DOI: 10.1016/j.scitotenv.2020.143550] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 11/01/2020] [Accepted: 11/02/2020] [Indexed: 06/12/2023]
Abstract
Chromophoric dissolved organic matter (CDOM) plays an important role in the biogeochemical cycle and energy flow of aquatic ecosystems. Thus, systematic and comprehensive understanding of CDOM dynamics is critically important for aquatic ecosystem management. CDOM spans multiple study fields, including analytical chemistry, biogeochemistry, water color remote sensing, and global environmental change. Here, we thoroughly summarize the progresses of recent studies focusing on the characterization, distribution, sources, composition, and fate of CDOM in inland waters. Characterization methods, remote sensing estimation, and biogeochemistry cycle processes were the hotspots of CDOM studies. Specifically, optical, isotope, and mass spectrometric techniques have been widely used to characterize CDOM abundance, composition, and sources. Remote sensing is an effective tool to map CDOM distribution with high temporal and spatial resolutions. CDOM dynamics are mainly determined by watershed-related processes, including rainfall discharge, groundwater, wastewater discharges/effluents, and biogeochemical cycling occurring in soil and water bodies. We highlight the underlying mechanisms of the photochemical degradation and microbial decomposition of CDOM, and emphasize that photochemical and microbial processes of CDOM in inland waters accelerate nutrient cycling and regeneration in the water column and also exacerbate global warming by releasing greenhouse gases. Future study directions to improve the understanding of CDOM dynamics in inland waters are proposed. This review provides an interdisciplinary view and new insights on CDOM dynamics in inland waters.
Collapse
Affiliation(s)
- Yunlin Zhang
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Lei Zhou
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yongqiang Zhou
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Liuqing Zhang
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China
| | - Xiaolong Yao
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Kun Shi
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Erik Jeppesen
- Department of Bioscience and Arctic Research Centre, Aarhus University, Vejlsøvej 25, DK-8600 Silkeborg, Denmark; Sino-Danish Centre for Education and Research, Beijing 100190, China; Limnology Laboratory, Department of Biological Sciences and Centre for Ecosystem Research and Implementation, Middle East Technical University, Ankara, Turkey.
| | - Qian Yu
- Department of Geoscience, University of Massachusetts, Amherst, MA, USA.
| | - Weining Zhu
- Ocean College, Zhejiang University, Zhoushan, Zhejiang, China.
| |
Collapse
|
12
|
Li Z, Juneau P, Lian Y, Zhang W, Wang S, Wang C, Shu L, Yan Q, He Z, Xu K. Effects of Titanium Dioxide Nanoparticles on Photosynthetic and Antioxidative Processes of Scenedesmus obliquus. PLANTS 2020; 9:plants9121748. [PMID: 33321890 PMCID: PMC7763043 DOI: 10.3390/plants9121748] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 12/07/2020] [Accepted: 12/07/2020] [Indexed: 02/05/2023]
Abstract
The effects of the photocatalytic toxicity of titanium dioxide nanoparticle (nano-TiO2) on phytoplankton are well understood. However, as UV light intensity decreases sharply with the depth of the water column, the effects of nano-TiO2 itself on deeper water phytoplankton, such as green algae, need further research. In this research, we investigated the effects of three sizes of TiO2 (10, 50 and 200 nm) on the photosynthetic and antioxidative processes of Scenedesmus obliquus in the absence of UV light. We found that 50 nm and 10 nm TiO2 (10 mg/L) inhibited growth rates and the maximal photosystem II quantum yield compared to the control in Scenedesmus obliquus. The minimal and maximal fluorescence yields, and the contents of reactive oxygen species and lipid peroxidation, increased, indicating that photosynthetic energy/electrons transferred to oxygen and induced oxidative stress in nano-TiO2-treated samples. In addition, we found that aggregations of algae and 10 nm TiO2 were present, which could induce cell membrane disruption, and vacuoles were induced to cope with nano-TiO2 stress in Scenedesmus obliquus. These results enhance our understanding of the effects of nano-TiO2 on the photosynthetic and antioxidative processes of green algae, and provide basic information for evaluating the ecotoxicity of nano-TiO2 in freshwater ecosystems.
Collapse
Affiliation(s)
- Zhou Li
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou 510006, Guangdong, China; (Z.L.); (Y.L.); (W.Z.); (S.W.); (C.W.); (L.S.); (Q.Y.)
| | - Philippe Juneau
- Department of Biological Sciences, GRIL-EcotoQ-TOXEN, Ecotoxicology of Aquatic Microorganisms Laboratory, Université du Québec à Montréal, Succ. Centre-Ville, Montréal, QC H3C 3P8, Canada;
| | - Yingli Lian
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou 510006, Guangdong, China; (Z.L.); (Y.L.); (W.Z.); (S.W.); (C.W.); (L.S.); (Q.Y.)
| | - Wei Zhang
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou 510006, Guangdong, China; (Z.L.); (Y.L.); (W.Z.); (S.W.); (C.W.); (L.S.); (Q.Y.)
| | - Shanquan Wang
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou 510006, Guangdong, China; (Z.L.); (Y.L.); (W.Z.); (S.W.); (C.W.); (L.S.); (Q.Y.)
| | - Cheng Wang
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou 510006, Guangdong, China; (Z.L.); (Y.L.); (W.Z.); (S.W.); (C.W.); (L.S.); (Q.Y.)
| | - Longfei Shu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou 510006, Guangdong, China; (Z.L.); (Y.L.); (W.Z.); (S.W.); (C.W.); (L.S.); (Q.Y.)
| | - Qingyun Yan
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou 510006, Guangdong, China; (Z.L.); (Y.L.); (W.Z.); (S.W.); (C.W.); (L.S.); (Q.Y.)
| | - Zhili He
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou 510006, Guangdong, China; (Z.L.); (Y.L.); (W.Z.); (S.W.); (C.W.); (L.S.); (Q.Y.)
- College of Agronomy, Hunan Agricultural University, Changsha 410128, Hunan, China
- Correspondence: (Z.H.); (K.X.)
| | - Kui Xu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou 510006, Guangdong, China; (Z.L.); (Y.L.); (W.Z.); (S.W.); (C.W.); (L.S.); (Q.Y.)
- Correspondence: (Z.H.); (K.X.)
| |
Collapse
|
13
|
Li D, Pan B, Zheng X, Jiang X, Zhao G, Han X. CDOM in the source regions of the Yangtze and Yellow Rivers, China: optical properties, possible sources, and their relationships with environmental variables. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:32856-32873. [PMID: 32524401 DOI: 10.1007/s11356-020-09385-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 05/19/2020] [Indexed: 06/11/2023]
Abstract
The source regions of the Yangtze and Yellow Rivers on the Qinghai-Tibet Plateau are extremely important water resources and ecological functional areas in China, and the ecological environment is fragile and sensitive to climate change. Chromophoric dissolved organic matter (CDOM) is an important component that plays a crucial role in the biogeochemical cycle in aquatic ecosystems. However, knowledge of the distribution characteristics of CDOM in this area is limited. In this study, the optical properties, possible sources of CDOM, and their relationships with environmental variables were investigated in the two regions. The results indicated that the CDOM absorption spectra of these two source regions had a high degree of consistency, and the absorption coefficient aCDOM(355) was small, with a mean of 2.07 ± 1.10 m-1. Two fluorescence components (C1 and C2) were identified and grouped into the humic-like component with parallel factor analysis (PARAFAC) of fluorescence excitation-emission matrices (EEMs), which exhibited highly similar (excitations/emission)max positions between each pair of components in the two regions. Comprehensive CDOM spectral absorption and fluorescence parameters suggested that CDOM was mainly derived from externally input humus, and the source region of the Yellow River showed stronger allochthonous sources. The dissolved organic carbon (DOC) gradients in the water affected the fluorescence intensity and indicated that the humic-like component was an important component of DOC. Water temperature (WT) and turbidity (Turb) positively affected the concentration of CDOM and the ability to absorb light in the aquatic ecosystems. Due to global warming, the rising temperature may lead to an increase in meltwater inflow in the source area and will also bring more external inputs through the runoff.
Collapse
Affiliation(s)
- Dianbao Li
- State Key Laboratory of Eco-hydraulic in Northwest Arid Region of China, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China
| | - Baozhu Pan
- State Key Laboratory of Eco-hydraulic in Northwest Arid Region of China, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China.
| | - Xing Zheng
- State Key Laboratory of Eco-hydraulic in Northwest Arid Region of China, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China
| | - Xiaoming Jiang
- State Key Laboratory of Eco-hydraulic in Northwest Arid Region of China, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China
| | - Gengnan Zhao
- State Key Laboratory of Eco-hydraulic in Northwest Arid Region of China, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China
| | - Xu Han
- State Key Laboratory of Eco-hydraulic in Northwest Arid Region of China, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China
| |
Collapse
|
14
|
Zhang Y, Shi K, Zhou Q, Zhou Y, Zhang Y, Qin B, Deng J. Decreasing underwater ultraviolet radiation exposure strongly driven by increasing ultraviolet attenuation in lakes in eastern and southwest China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 720:137694. [PMID: 32325604 DOI: 10.1016/j.scitotenv.2020.137694] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 02/24/2020] [Accepted: 03/02/2020] [Indexed: 05/20/2023]
Abstract
Underwater light attenuation plays an important role in modulating aquatic ecosystems and is considered a sentinel of climate change and human activity. However, knowledge of the long-term exposure of underwater ultraviolet radiation (UVR) in aquatic ecosystem is still very limited. We carried out extensive UVR measurements in different seasons in five lakes at different altitudes, collected long-term Secchi disk depth (SDD) data, developed the models between UVR diffuse attenuation coefficient (Kd) and SDD, and further assessed the long-term underwater UVR exposure. Observation results from five lakes including 259 samples showed large spatial variabilities of Kd(313) (UVB) from 0.83 to 5.91 m-1 and Kd(340) (UVA) from 0.51 to 4.67 m-1. Chromophoric dissolved organic matter (CDOM) absorption coefficients were significantly correlated with Kd(313) and Kd(340). Thus, the effects of climate change and human activity on CDOM abundance, source and composition may significantly alter UVR attenuation in aquatic environments. The long-term underwater UVR exposure, which was estimated from significant positive correlations between 1/SDD and Kd(313) and Kd(340), and incident UVR, significantly decreased in Lake Fuxianhu, Lake Erhai, and Lake Qiandaohu. The regime shift from clear water state to turbid state in Lake Erhai around 2001-2003 dramatically decreased underwater UVR exposure. In conclusion, increasing UVR attenuation played a more important role in determining underwater UVR exposure than decreasing incident UVR with the relative contributions of 89.9% and 87.7% in Lake Fuxianhu, 98.0% and 97.7% in Lake Erhai, 94.4% and 92.5% in Lake Qiandaohu for UVB and UVA exposure, respectively. This is the first study to elucidate the long-term trend of underwater UVR exposure considering both increasing UVR attenuation and decreasing incident UVR.
Collapse
Affiliation(s)
- Yunlin Zhang
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Kun Shi
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qichao Zhou
- Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Science, Yunnan University, Kunming 650500, China
| | - Yongqiang Zhou
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yibo Zhang
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Boqiang Qin
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jianming Deng
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| |
Collapse
|
15
|
Ren L, Wang P, Wang C, Paerl HW, Wang H. Effects of phosphorus availability and phosphorus utilization behavior of Microcystis aeruginosa on its adaptation capability to ultraviolet radiation. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 256:113441. [PMID: 31672370 DOI: 10.1016/j.envpol.2019.113441] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 10/10/2019] [Accepted: 10/18/2019] [Indexed: 05/20/2023]
Abstract
Phosphorus (P) plays a critical role in eutrophication and algal growth; therefore, improving our understanding of the impact of P is essential to control harmful algal blooms. In this study, Microcystis aeruginosa was treated with 5-h ambient irradiation in the medium with different dissolved inorganic P (DIP) concentrations, DIP-free, moderate-DIP, and high-DIP, to explore its growth and other physiological responses. Compared to photosynthetically active radiation (PAR), UV-A (320-400 nm) and UV-B (280-320 nm) radiation had inhibitive effects on the photosynthesis and growth of M. aeruginosa, while high P availability could alleviate or eliminate the negative effects of UV radiation. The photosynthetic parameters had a minimum reduction and quickly recovered after re-inoculation under high-DIP conditions. Confirmed by SEM, photosynthetic pigments, the generation of reactive oxygen species (ROS), superoxide dismutase (SOD) activity and other methods, ambient UV radiation exerted oxidative stresses rather than direct lethal effects on M. aeruginosa. Photosynthetic parameters indicated that algal UV-adaptation processes could include decreasing photo-induced damages and increasing self-repair efficiency. The P acquired by M. aeruginosa cells can have two function, which included alleviating UV-induced negative effects and sustaining algal growth. Consequently, UV-adaptation processes of M. aeruginosa resulted in an elevated demand for DIP, which resulted to increased P uptake rates and cellular P quota under moderate and high-DIP conditions. Therefore, the production of carotenoid and phycocyanin, and SOD activity increased under UV stress, leading to a better adaptation capability of M. aeruginosa and decreased negative effects of UV radiation on its growth. Overall, our findings demonstrated the significant interactive effects of P enrichment and irradiation on typical cyanobacteria, and the strong adaptation capability of M. aeruginosa in the eutrophic UV-radiated waters.
Collapse
Affiliation(s)
- Lingxiao Ren
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing, 210098, PR China; College of Environment, Hohai University, Nanjing, 210098, PR China; College of Environmental Engineering, Nanjing Institute of Technology, 211167, Nanjing, PR China
| | - Peifang Wang
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing, 210098, PR China; College of Environment, Hohai University, Nanjing, 210098, PR China.
| | - Chao Wang
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing, 210098, PR China; College of Environment, Hohai University, Nanjing, 210098, PR China
| | - Hans W Paerl
- University of North Carolina at Chapel Hill, Institute of Marine Sciences, Morehead City, NC, USA
| | - Huiya Wang
- College of Environmental Engineering, Nanjing Institute of Technology, 211167, Nanjing, PR China
| |
Collapse
|
16
|
Zhang R, Li Y, Pan B, Li Y, Liu A, Li X. Increased expression of hub gene CXCL10 in peripheral blood mononuclear cells of patients with systemic lupus erythematosus. Exp Ther Med 2019; 18:4067-4075. [PMID: 31616519 PMCID: PMC6781829 DOI: 10.3892/etm.2019.8013] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 08/23/2019] [Indexed: 12/11/2022] Open
Abstract
Systemic lupus erythematosus (SLE) is a prototypical autoimmune disease, characterized by overactive inflammation and aberrant activation of lymphocytes. Chemokine C-X-C motif ligand 10 (CXCL10) has an important role in the initiation and deterioration of SLE. However, the expression levels of CXCL10 mRNA in T-helper (Th) cells and B lymphocytes from SLE patients have remained elusive. In the present study, a Bioinformatics analysis of differentially expressed gene (DEG) profiles obtained from RNA sequencing data for three matched samples was performed to explore the hub genes, mainly through Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes and protein-protein interaction analysis. Furthermore, the expression of CXCL10 in peripheral blood mononuclear cells (PBMCs), CD4+ Th cells and CD19+ B cells of 108 subjects, including 66 SLE patients and 42 healthy controls, was confirmed by reverse transcription-quantitative PCR. In addition, 4 single-nucleotide polymorphism (SNP) loci in the 3'-untranslated region of CXCL10 were assessed using the Snapshot SNP genotyping assay. A total of 152 clustered DEGs mainly accumulated in immune-associated GO terms and interferon-associated pathways were identified. The expression of CXCL10, one of the central genes in the interaction network cluster (the degree of interaction, MCODE score=28.414), was 6.27-fold higher in SLE patients compared with control patients. Furthermore, CXCL10 mRNA was confirmed to be elevated in PBMCs and CD19+ B cells of patients with SLE (P<0.001 for the two cell types). However, no significant difference in CD4+ T lymphocytes was present (P=0.881). In addition, no polymorphism was identified in four selected loci from the samples. Taken together, the present results demonstrated that CXCL10, one of the hub genes in the pathogenesis of SLE, is upregulated in PBMCs and B lymphocytes of patients with SLE, although none of the SNPs selected for analysis in the present study were identified to have any potential associations with SLE.
Collapse
Affiliation(s)
- Ruixian Zhang
- Department of Dermatology, The Second Affiliated Hospital of Kunming Medical University, Kunming, Yunnan 650101, P.R. China.,Institute of Environmental Hygiene, Yunnan Center for Disease Control and Prevention, Kunming, Yunnan 650022, P.R. China
| | - Ya Li
- Department of Clinical Laboratory, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan 650031, P.R. China
| | - Bangpin Pan
- Department of Dermatology, The Second Affiliated Hospital of Kunming Medical University, Kunming, Yunnan 650101, P.R. China
| | - Yi Li
- Department of Dermatology, The Second Affiliated Hospital of Kunming Medical University, Kunming, Yunnan 650101, P.R. China
| | - Aimin Liu
- Basic Nursing Teaching Department of Kunming Medical University, Kunming, Yunnan 650500, P.R. China
| | - Xiaolan Li
- Department of Dermatology, The Second Affiliated Hospital of Kunming Medical University, Kunming, Yunnan 650101, P.R. China
| |
Collapse
|
17
|
Zhou Q, Zhang Y, Li K, Huang L, Yang F, Zhou Y, Chang J. Seasonal and spatial distributions of euphotic zone and long-term variations in water transparency in a clear oligotrophic Lake Fuxian, China. J Environ Sci (China) 2018; 72:185-197. [PMID: 30244745 DOI: 10.1016/j.jes.2018.01.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 01/05/2018] [Accepted: 01/08/2018] [Indexed: 06/08/2023]
Abstract
To assess the seasonal and spatial variations and long-term trends in water optical properties in Lake Fuxian, investigations based on field work in four seasons and a long-term analysis of data from 1980 to 2014 were conducted. The results show that there was no significant variation in the euphotic depth (Zeu) across the four seasons, and no significant correlations between Zeu and potential influencing factors in seasons other than summer, suggesting that the water itself may be a major factor regulating the Zeu in general. Nevertheless, significant differences in Zeu between the north region (NR) and the south region (SR) were observed in all seasonal tests except spring. This finding relates to a higher abundance of chromophoric dissolved organic matter (CDOM) in the NR due to runoff, especially in the rainy seasons (summer and autumn). CDOM and its terrigenous component had an important impact on Zeu in summer, with the highest precipitation, and impacts from suspended solids and non-algal particles were also found in the NR in summer. The Secchi disk depth in the lake decreased clearly over the years, with significantly negative correlations with the increasing permanganate index and air temperature, implying that organic contaminants (CDOM and/or phytoplankton) are important regulators of water transparency. We estimate that the combined effects of climate warming and changes in land use and land cover are also indirect regulating factors. These findings should be considered in the protection of Lake Fuxian, owing to the importance of light penetration in aquatic ecosystems.
Collapse
Affiliation(s)
- Qichao Zhou
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed, Yunnan Institute of Environmental Science (Kunming China International Research Center for Plateau Lake), Kunming 650034, China.
| | - Yunlin Zhang
- Taihu Laboratory for Lake Ecosystem Research, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.
| | - Kaidi Li
- Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed, Yunnan Institute of Environmental Science (Kunming China International Research Center for Plateau Lake), Kunming 650034, China; School of Ecology and Environmental Science, Yunnan University, Kunming 650091, China
| | - Licheng Huang
- Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed, Yunnan Institute of Environmental Science (Kunming China International Research Center for Plateau Lake), Kunming 650034, China
| | - Fengle Yang
- Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed, Yunnan Institute of Environmental Science (Kunming China International Research Center for Plateau Lake), Kunming 650034, China
| | - Yuanyang Zhou
- Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed, Yunnan Institute of Environmental Science (Kunming China International Research Center for Plateau Lake), Kunming 650034, China; School of Ecology and Environmental Science, Yunnan University, Kunming 650091, China
| | - Junjun Chang
- School of Ecology and Environmental Science, Yunnan University, Kunming 650091, China
| |
Collapse
|
18
|
Zhou C, Chen J, Xie H, Zhang YN, Li Y, Wang Y, Xie Q, Zhang S. Modeling photodegradation kinetics of organic micropollutants in water bodies: A case of the Yellow River estuary. JOURNAL OF HAZARDOUS MATERIALS 2018; 349:60-67. [PMID: 29414753 DOI: 10.1016/j.jhazmat.2018.01.051] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 12/16/2017] [Accepted: 01/25/2018] [Indexed: 06/08/2023]
Abstract
Predicting photodegradation rate constants (k) of pollutants in water bodies is important for assessing their persistence and fate. This prediction used to be based on the k values determined under laboratory conditions that seldom consider underwater downward sunlight attenuation in the field. We studied a procedure to predict k taking the Yellow River estuary and two model chemicals (sulfamethoxazole and acyclovir) as a case. Models were developed for predicting underwater sunlight intensities from optically-active substances. Based on the predicted underwater sunlight intensities, hourly variation of k for the model compounds was predicted as a function of water depth, for a fresh water, an estuarine water and a seawater body in the estuary. Results show that photodegradation half-lives (t1/2) of the two compounds will be underestimated by dozens of times if underwater downward sunlight attenuation and intensity variation are not considered. Outdoor validation experiments show the maximum deviation between the predicted and measured k values is a factor of 2. The developed models can be employed to predict k of environmental chemicals in coastal water bodies once they are locally calibrated.
Collapse
Affiliation(s)
- Chengzhi Zhou
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian 116024, China
| | - Jingwen Chen
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian 116024, China.
| | - Huaijun Xie
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian 116024, China
| | - Ya-Nan Zhang
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian 116024, China
| | - Yingjie Li
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian 116024, China
| | - Yan Wang
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian 116024, China
| | - Qing Xie
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian 116024, China
| | - Siyu Zhang
- Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China
| |
Collapse
|
19
|
Zhang Y, Zhou Y, Shi K, Qin B, Yao X, Zhang Y. Optical properties and composition changes in chromophoric dissolved organic matter along trophic gradients: Implications for monitoring and assessing lake eutrophication. WATER RESEARCH 2018; 131:255-263. [PMID: 29304379 DOI: 10.1016/j.watres.2017.12.051] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Revised: 12/12/2017] [Accepted: 12/19/2017] [Indexed: 06/07/2023]
Abstract
Chromophoric dissolved organic matter (CDOM) is an important optically active substance in aquatic environments and plays a key role in light attenuation and in the carbon, nitrogen and phosphorus biogeochemical cycles. Although the optical properties, abundance, sources, cycles, compositions and remote sensing estimations of CDOM have been widely reported in different aquatic environments, little is known about the optical properties and composition changes in CDOM along trophic gradients. Therefore, we collected 821 samples from 22 lakes along a trophic gradient (oligotrophic to eutrophic) in China from 2004 to 2015 and determined the CDOM spectral absorption and nutrient concentrations. The total nitrogen (TN), total phosphorus (TP), and chlorophyll a (Chla) concentrations and the Secchi disk depth (SDD) ranged from 0.02 to 24.75 mg/L, 0.002-3.471 mg/L, 0.03-882.66 μg/L, and 0.05-17.30 m, respectively. The trophic state index (TSI) ranged from 1.55 to 98.91 and covered different trophic states, from oligotrophic to hyper-eutrophic. The CDOM absorption coefficient at 254 nm (a(254)) ranged from 1.68 to 92.65 m-1. Additionally, the CDOM sources and composition parameters, including the spectral slope and relative molecular size value, exhibited a substantial variability from the oligotrophic level to other trophic levels. The natural logarithm value of the CDOM absorption, lna(254), is highly linearly correlated with the TSI (r2 = 0.92, p < .001, n = 821). Oligotrophic lakes are distinguished by a(254)<4 m-1, and mesotrophic and eutrophic lakes are classified as 4 ≤ a(254)≤10 and a(254)>10 m-1, respectively. The results suggested that the CDOM absorption coefficient a(254) might be a more sensitive single indicator of the trophic state than TN, TP, Chla and SDD. Therefore, we proposed a CDOM absorption coefficient and determined the threshold for defining the trophic state of a lake. Several advantages of measuring and estimating CDOM, including rapid experimental measurements, potential in situ optical sensor measurements and large-spatial-scale remote sensing estimations, make it superior to traditional TSI techniques for the rapid monitoring and assessment of lake trophic states.
Collapse
Affiliation(s)
- Yunlin Zhang
- Taihu Lake Laboratory Ecosystem Research Station, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China; University of Chinese Academy of Sciences, Beijing, China.
| | - Yongqiang Zhou
- Taihu Lake Laboratory Ecosystem Research Station, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Kun Shi
- Taihu Lake Laboratory Ecosystem Research Station, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Boqiang Qin
- Taihu Lake Laboratory Ecosystem Research Station, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Xiaolong Yao
- Taihu Lake Laboratory Ecosystem Research Station, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Yibo Zhang
- Taihu Lake Laboratory Ecosystem Research Station, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China; University of Chinese Academy of Sciences, Beijing, China
| |
Collapse
|
20
|
Bachmann RW, Hoyer MV, Croteau AC, Canfield DE. Factors related to Secchi depths and their stability over time as determined from a probability sample of US lakes. ENVIRONMENTAL MONITORING AND ASSESSMENT 2017; 189:206. [PMID: 28374189 DOI: 10.1007/s10661-017-5911-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 03/23/2017] [Indexed: 06/07/2023]
Abstract
A probabilistic sample of lakes in the 48 coterminous US lakes was made by the United States Environmental Protection Agency in the 2007 National Lakes Assessment. Because of the statistical design, the results of our analyses of Secchi depths (SD) apply to a population of 45,265 lakes. We found statistically significant differences in mean Secchi depths between natural (1.57 m) and man-made lakes (1.18 m). The most important variable correlated with SD was turbidity, an optical measure related to suspended particles in the water column. For most lakes, chlorophyll a was highly correlated with both turbidity and SD, but several lakes had more turbidity and lower SD than expected based on chlorophyll a alone, indicating that non-algal suspended solids were an important factor. On an ecoregion basis, the non-algal suspended solids in the lake waters were related to the average levels of suspended solids in streams located in that ecoregion, and the non-algal suspended solids were more important in man-made than natural lakes. Phosphorus and nitrogen were directly correlated with chlorophyll a and turbidity and inversely correlated with SD. Based on diatom-inferred Secchi depths for the tops and bottoms of sediment cores from lakes in Ecoregions VIII and VII (excluding lakes in Minnesota) representing 40% of the natural lakes in the US, there has been no decrease in water transparency in that population of lakes in the past 70 or more years when the US population increased by 134%. We do not have information to determine if the other 60% of lakes have or have not changed.
Collapse
Affiliation(s)
- Roger W Bachmann
- Fisheries and Aquatic Sciences, School of Forest Resources and Conservation, University of Florida, 7922 NW 71 St., Gainesville, FL, 32653, USA.
| | - Mark V Hoyer
- Fisheries and Aquatic Sciences, School of Forest Resources and Conservation, University of Florida, 7922 NW 71 St., Gainesville, FL, 32653, USA
| | - Amanda C Croteau
- Fisheries and Aquatic Sciences, School of Forest Resources and Conservation, University of Florida, 7922 NW 71 St., Gainesville, FL, 32653, USA
| | - Daniel E Canfield
- Fisheries and Aquatic Sciences, School of Forest Resources and Conservation, University of Florida, 7922 NW 71 St., Gainesville, FL, 32653, USA
| |
Collapse
|
21
|
Zhang Y, Liu X, Osburn CL, Wang M, Qin B, Zhou Y. Photobleaching response of different sources of chromophoric dissolved organic matter exposed to natural solar radiation using absorption and excitation-emission matrix spectra. PLoS One 2013; 8:e77515. [PMID: 24204852 PMCID: PMC3808427 DOI: 10.1371/journal.pone.0077515] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Accepted: 09/03/2013] [Indexed: 11/18/2022] Open
Abstract
CDOM biogeochemical cycle is driven by several physical and biological processes such as river input, biogeneration and photobleaching that act as primary sinks and sources of CDOM. Watershed-derived allochthonous (WDA) and phytoplankton-derived autochthonous (PDA) CDOM were exposed to 9 days of natural solar radiation to assess the photobleaching response of different CDOM sources, using absorption and fluorescence (excitation-emission matrix) spectroscopy. Our results showed a marked decrease in total dissolved nitrogen (TDN) concentration under natural sunlight exposure for both WDA and PDA CDOM, indicating photoproduction of ammonium from TDN. In contrast, photobleaching caused a marked increase in total dissolved phosphorus (TDP) concentration for both WDA and PDA CDOM. Thus TDN∶TDP ratios decreased significantly both for WDA and PDA CDOM, which partially explained the seasonal dynamic of TDN∶TDP ratio in Lake Taihu. Photobleaching rate of CDOM absorption a(254), was 0.032 m/MJ for WDA CDOM and 0.051 m/MJ for PDA CDOM from days 0–9, indicating that phototransformations were initially more rapid for the newly produced CDOM from phytoplankton than for the river CDOM. Extrapolation of these values to the field indicated that 3.9%–5.1% CDOM at the water surface was photobleached and mineralized every day in summer in Lake Taihu. Photobleaching caused the increase of spectral slope, spectral slope ratio and molecular size, indicating the CDOM mean molecular weight decrease which was favorable to further microbial degradation of mineralization. Three fluorescent components were validated in parallel factor analysis models calculated separately for WDA and PDA CDOM. Our study suggests that the humic-like fluorescence materials could be rapidly and easily photobleached for WDA and PDA CDOM, but the protein-like fluorescence materials was not photobleached and even increased from the transformation of the humic-like fluorescence substance to the protein-like fluorescence substance. Photobleaching was an important driver of CDOM and nutrients biogeochemistry in lake water.
Collapse
Affiliation(s)
- Yunlin Zhang
- Taihu Lake Laboratory Ecosystem Research Station, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
- * E-mail:
| | - Xiaohan Liu
- Taihu Lake Laboratory Ecosystem Research Station, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Christopher L. Osburn
- Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh, North Carolina, United States of America
| | - Mingzhu Wang
- Taihu Lake Laboratory Ecosystem Research Station, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Boqiang Qin
- Taihu Lake Laboratory Ecosystem Research Station, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
| | - Yongqiang Zhou
- Taihu Lake Laboratory Ecosystem Research Station, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
- University of Chinese Academy of Sciences, Beijing, China
| |
Collapse
|
22
|
Zhang Y, Liu X, Yin Y, Wang M, Qin B. A simple optical model to estimate diffuse attenuation coefficient of photosynthetically active radiation in an extremely turbid lake from surface reflectance. OPTICS EXPRESS 2012; 20:20482-20493. [PMID: 23037096 DOI: 10.1364/oe.20.020482] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Accurate estimation of the diffuse attenuation coefficient is critical for our understanding and modelling of key physical, chemical, and biological processes in water bodies. For extremely turbid, shallow, Lake Taihu in China, we synchronously monitored the diffuse attenuation coefficient of photosynthetically active radiation (Kd(PAR)) and the remote sensing reflectance at 134 sites. Kd(PAR)) varied greatly among different sites from 1.62 to 14.68 m(-1) with a mean value of 5.62 ± 2.99 m(-1). A simple optical model from near-infrared remote sensing reflectance of MODIS channels 2 (859 nm) and 15 (748 nm) was calibrated, and validated, to estimate Kd(PAR). With the simple optical model, the root mean square error and mean relative error were 0.95 m(-1) and 17.0% respectively at 748 nm, and 0.98 m(-1) and 17.6% at 859 nm, based on an independent validation data set. Our results showed a good precision of estimation for Kd(PAR) using the new simple optical model, contrasting with the poor estimations derived from existing empirical and semi-analytical models developed in clear, open ocean waters or slightly turbid coastal waters. Although at 748 nm the model had slightly higher precision than at 859 nm, the spatial resolution at 859 nm was four times that at 748 nm. Therefore, we propose a new model based on the MODIS-derived normalized water-leaving radiances at a wavelength of 859 nm, for accurate retrieval of Kd(PAR) in extremely turbid, shallow lakes with Kd(PAR) larger than 1.5 m(-1).
Collapse
Affiliation(s)
- Yunlin Zhang
- Taihu Lake Laboratory Ecosystem Research Station, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China.
| | | | | | | | | |
Collapse
|
23
|
Environmental effects of ozone depletion and its interactions with climate change: progress report, 2011. Photochem Photobiol Sci 2012; 11:13-27. [DOI: 10.1039/c1pp90033a] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
|
24
|
Zhang Y, Yin Y, Feng L, Zhu G, Shi Z, Liu X, Zhang Y. Characterizing chromophoric dissolved organic matter in Lake Tianmuhu and its catchment basin using excitation-emission matrix fluorescence and parallel factor analysis. WATER RESEARCH 2011; 45:5110-5122. [PMID: 21840562 DOI: 10.1016/j.watres.2011.07.014] [Citation(s) in RCA: 120] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Revised: 07/06/2011] [Accepted: 07/11/2011] [Indexed: 05/31/2023]
Abstract
Chromophoric dissolved organic matter (CDOM) is an important optically active substance that transports nutrients, heavy metals, and other pollutants from terrestrial to aquatic systems and is used as a measure of water quality. To investigate how the source and composition of CDOM changes in both space and time, we used chemical, spectroscopic, and fluorescence analyses to characterize CDOM in Lake Tianmuhu (a drinking water source) and its catchment in China. Parallel factor analysis (PARAFAC) identified three individual fluorophore moieties that were attributed to humic-like and protein-like materials in 224 water samples collected between December 2008 and September 2009. The upstream rivers contained significantly higher concentrations of CDOM than did the lake water (a(350) of 4.27±2.51 and 2.32±0.59 m(-1), respectively), indicating that the rivers carried a substantial load of organic matter to the lake. Of the three main rivers that flow into Lake Tianmuhu, the Pingqiao River brought in the most CDOM from the catchment to the lake. CDOM absorption and the microbial and terrestrial humic-like components, but not the protein-like component, were significantly higher in the wet season than in other seasons, indicating that the frequency of rainfall and runoff could significantly impact the quantity and quality of CDOM collected from the catchment. The different relationships between the maximum fluorescence intensities of the three PARAFAC components, CDOM absorption, and chemical oxygen demand (COD) concentration in riverine and lake water indicated the difference in the composition of CDOM between Lake Tianmuhu and the rivers that feed it. This study demonstrates the utility of combining excitation-emission matrix fluorescence and PARAFAC to study CDOM dynamics in inland waters.
Collapse
Affiliation(s)
- Yunlin Zhang
- Taihu Lake Laboratory Ecosystem Research Station, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.
| | | | | | | | | | | | | |
Collapse
|