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Li J, Liang E, Deng C, Li B, Cai H, Ma R, Xu Q, Liu J, Wang T. Labile dissolved organic matter (DOM) and nitrogen inputs modified greenhouse gas dynamics: A source-to-estuary study of the Yangtze River. Water Res 2024; 253:121318. [PMID: 38387270 DOI: 10.1016/j.watres.2024.121318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Revised: 02/07/2024] [Accepted: 02/14/2024] [Indexed: 02/24/2024]
Abstract
Although rivers are increasingly recognized as essential sources of greenhouse gases (GHG) to the atmosphere, few systematic efforts have been made to reveal the drivers of spatiotemporal variations of dissolved GHG (dGHG) in large rivers under increasing anthropogenic stress and intensified hydrological cycling. Here, through a source-to-estuary survey of the Yangtze River in March (spring) and October (autumn) of 2018, we revealed that labile dissolved organic matter (DOM) and nitrogen inputs remarkably modified the spatiotemporal distribution of dGHG. The average partial pressure of CO2 (pCO2), CH4 and N2O concentrations of all sampling sites in the Yangtze River were 1015 ± 225 μatm, and 87.5± 36.5 nmol L-1, and 20.3 ± 6.6 nmol L-1, respectively, significantly lower than the global average. In terms of longitudinal and seasonal variations, higher GHG concentrations were observed in the middle-lower reach in spring. The dominant drivers of spatiotemporal variations in dGHG were labile, protein-like DOM components and nitrogen level. Compared with the historical data of dGHG from published literature, we found a significant increase in N2O concentrations in the Yangtze River during 2004-2018, and the increasing trend was consistent with the rising riverine nitrogen concentrations. Our study emphasized the critical roles of labile DOM and nitrogen inputs in driving the spatial hotspots, seasonal variations and annual trends of dGHG. These findings can contribute to constraining the global GHG budget estimations and controls of GHG emission in large rivers in response to global change.
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Affiliation(s)
- Jiarui Li
- College of Environmental Sciences and Engineering, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, PR China; State Environmental Protection Key Laboratory of All Materials Flux in River Ecosystems, Beijing 100871, PR China
| | - Enhang Liang
- College of Environmental Sciences and Engineering, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, PR China; State Environmental Protection Key Laboratory of All Materials Flux in River Ecosystems, Beijing 100871, PR China
| | - Chunfang Deng
- College of Environmental Sciences and Engineering, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, PR China; State Environmental Protection Key Laboratory of All Materials Flux in River Ecosystems, Beijing 100871, PR China
| | - Bin Li
- College of Environmental Sciences and Engineering, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, PR China; State Environmental Protection Key Laboratory of All Materials Flux in River Ecosystems, Beijing 100871, PR China
| | - Hetong Cai
- College of Environmental Sciences and Engineering, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, PR China; State Environmental Protection Key Laboratory of All Materials Flux in River Ecosystems, Beijing 100871, PR China
| | - Ruoqi Ma
- College of Environmental Sciences and Engineering, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, PR China; State Environmental Protection Key Laboratory of All Materials Flux in River Ecosystems, Beijing 100871, PR China; General Institute of Water Resources and Hydropower Planning and Design, Ministry of Water Resources, Beijing 100120, PR China
| | - Qiang Xu
- School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin 15030, PR China
| | - Jiaju Liu
- Research Center for Integrated Control of Watershed Water Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, PR China.
| | - Ting Wang
- College of Environmental Sciences and Engineering, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, PR China; State Environmental Protection Key Laboratory of All Materials Flux in River Ecosystems, Beijing 100871, PR China.
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Lv P, Sun S, Li Y, Zhao S, Zhang J, Hu Y, Yue P, Zuo X. Growing-season drought and nitrogen addition interactively impair grassland ecosystem stability by reducing species diversity, asynchrony, and stability. Sci Total Environ 2024; 912:169122. [PMID: 38065502 DOI: 10.1016/j.scitotenv.2023.169122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 11/28/2023] [Accepted: 12/03/2023] [Indexed: 01/18/2024]
Abstract
Aboveground net primary productivity controls the amount of energy available to sustain all living organisms, and its sustainable provision relies on the stability of grassland ecosystems. Human activities leading to global changes, such as increased nitrogen (N) deposition and the more frequent occurrence of extreme precipitation events, with N addition increasing the sensitivity of ecosystem production stability to changes in the precipitation regime. However, whether N addition, in combination with seasonal precipitation increases or severe drought, affects ecosystem stability remains unclear. In this study, we conducted a six-year environmental change monitoring experiment in a semiarid grassland in northern China to test the effects of N addition, seasonal drought, and precipitation increases on the temporal stability of ecosystem productivity. Our study revealed that an interaction between drought and N addition reduced species diversity, species asynchrony, species stability, and thus ecosystem stability. These environmental change drivers (except for precipitation increase) induced a positive relationship between species asynchrony and diversity, whereas N addition interactively with drought and precipitation increase led to a negative relationship between diversity and species stability. Only N addition interactively with drought induced a positive species diversity-ecosystem stability relationship because lower species stability was overcome by increased species asynchrony. Our study is great importance to illustrate that production temporal stability tends to be inhibited with drought, though interactively with nutrient N addition. These findings highlight the primary role of asynchronous dynamics among species in modulating the effects of environmental change on diversity-stability relationships.
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Affiliation(s)
- Peng Lv
- Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; Urat Desert-Grassland Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; Key Laboratory of Stress Physiology and Ecology in Cold and Arid Regions, Gansu Province, Lanzhou 730000, China
| | - Shanshan Sun
- Urat Desert-Grassland Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuqiang Li
- Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; Key Laboratory of Stress Physiology and Ecology in Cold and Arid Regions, Gansu Province, Lanzhou 730000, China
| | - Shenglong Zhao
- College of Resources and Environmental Engineering, Tianshui Normal University, Tianshui 741000, China
| | - Jing Zhang
- Information Center, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Ya Hu
- Urat Desert-Grassland Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; Key Laboratory of Stress Physiology and Ecology in Cold and Arid Regions, Gansu Province, Lanzhou 730000, China
| | - Ping Yue
- Urat Desert-Grassland Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; Key Laboratory of Stress Physiology and Ecology in Cold and Arid Regions, Gansu Province, Lanzhou 730000, China
| | - Xiaoan Zuo
- Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; Urat Desert-Grassland Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; Key Laboratory of Stress Physiology and Ecology in Cold and Arid Regions, Gansu Province, Lanzhou 730000, China.
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3
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Wu W, Niu X, Yan Z, Li S, Comer-Warner SA, Tian H, Li SL, Zou J, Yu G, Liu CQ. Agricultural ditches are hotspots of greenhouse gas emissions controlled by nutrient input. Water Res 2023; 242:120271. [PMID: 37399689 DOI: 10.1016/j.watres.2023.120271] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 06/05/2023] [Accepted: 06/24/2023] [Indexed: 07/05/2023]
Abstract
Agricultural ditches are pervasive in agricultural areas and are potential greenhouse gas (GHG) hotspots, since they directly receive abundant nutrients from neighboring farmlands. However, few studies measure GHG concentrations or fluxes in this particular water course, likely resulting in underestimations of GHG emissions from agricultural regions. Here we conducted a one-year field study to investigate the GHG concentrations and fluxes from typical agricultural ditch systems, which included four different types of ditches in an irrigation district located in the North China Plain. The results showed that almost all the ditches were large GHG sources. The mean fluxes were 333 μmol m-2 h-1 for CH4, 7.1 mmol m-2 h-1 for CO2, and 2.4 μmol m-2 h-1 for N2O, which were approximately 12, 5, and 2 times higher, respectively, than that in the river connecting to the ditch systems. Nutrient input was the primary driver stimulating GHG production and emissions, resulting in GHG concentrations and fluxes increasing from the river to ditches adjacent to farmlands, which potentially received more nutrients. Nevertheless, the ditches directly connected to farmlands showed lower GHG concentrations and fluxes compared to the ditches adjacent to farmlands, possibly due to seasonal dryness and occasional drainage. All the ditches covered approximately 3.3% of the 312 km2 farmland area in the study district, and the total GHG emission from the ditches in this area was estimated to be 26.6 Gg CO2-eq yr-1, with 17.5 Gg CO2, 0.27 Gg CH4, and 0.006 Gg N2O emitted annually. Overall, this study demonstrated that agricultural ditches were hotspots of GHG emissions, and future GHG estimations should incorporate this ubiquitous but underrepresented water course.
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Affiliation(s)
- Wenxin Wu
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Xueqi Niu
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Zhifeng Yan
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China; Critical Zone Observatory of Bohai Coastal Region, Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin 300072, China.
| | - Siyue Li
- Institute of Changjiang Water Environment and Ecological Security, School of Environmental Ecology and Biological Engineering, Key Laboratory for Green Chemical Process of Ministry of Education, Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education, Hubei Key Laboratory of Novel Reactor and Green Chemical Technology, Wuhan Institute of Technology, Wuhan 430205, China
| | - Sophie A Comer-Warner
- School of Geography, Earth and Environmental Science, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Hanqin Tian
- Department of Earth and Environmental Sciences, Boston College, Schiller Institute for Integrated Science and Society, Chestnut Hill, MA 02467, United States
| | - Si-Liang Li
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China; Critical Zone Observatory of Bohai Coastal Region, Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin 300072, China
| | - Jianwen Zou
- Key Laboratory of Low-carbon and Green Agriculture in Southeastern China, Ministry of Agriculture and Rural Affairs, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
| | - Guirui Yu
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China; Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Cong-Qiang Liu
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China; Critical Zone Observatory of Bohai Coastal Region, Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin 300072, China; Haihe Laboratory of Sustainable Chemical Transformations, Tianjin 300072, China
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Huang Y, Fu M, Chen G, Zhang J, Xu P, Pan L, Zhang X, Chen X. Reducing the water residence time is inadequate to limit the algal proliferation in eutrophic lakes. J Environ Manage 2023; 330:117177. [PMID: 36603259 DOI: 10.1016/j.jenvman.2022.117177] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 12/24/2022] [Accepted: 12/28/2022] [Indexed: 06/17/2023]
Abstract
The eutrophication problem now threatens many lakes and reservoirs. To avoid the occurrence of algal blooms, some cities try to increase the flow rate or directly choose lakes or reservoirs with a short water residence time (WRT) as drinking water sources. However, up to now, whether such a strategy can achieve its goal is still unclear. In this study, a newly restored lake with a WRT of approximately 3 days was chosen to investigate algal growth potential as well as its responses to external nitrogen (N) and phosphorus (P) inputs. The results suggested that although the water quality of the lake could generally meet the environmental quality standards for surface water, dissolved inorganic nitrogen reached a high level with an average value of 1.58 mg/L. Meanwhile, a considerable increase in Chl-a concentration was observed across the flow direction. Especially, in July, Chl-a concentration at the site near the outlet was 8.1 times higher than that at the inlet, and cyanobacteria became the dominant species accounting for 83% of the total cell density. Nutrient enrichment experiments showed that algae could grow rapidly within 3 days with average specific growth rates (μ) of 0.36-0.42 d-1. The addition of N and P furtherly promoted the algal growth, and μ values of the treatments with P addition were the highest at 0.67-0.83 d-1. These results indicated that even if the WRT was reduced to 3 days, the risk of the occurrence of algal blooms still exists, and this undesirable trend would be enhanced by the short-term external nutrient input. Our findings indicated that the hydrodynamic control measures may not be entirely successful in protecting the drinking water source from algal blooms, especially when its influent has already been under eutrophication.
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Affiliation(s)
- Yingying Huang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, 500 Dong Chuan Road, Shanghai, 200241, China.
| | - Min Fu
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, 500 Dong Chuan Road, Shanghai, 200241, China
| | - Guiqin Chen
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, 500 Dong Chuan Road, Shanghai, 200241, China
| | - Jieyun Zhang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, 500 Dong Chuan Road, Shanghai, 200241, China
| | - Ping Xu
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, 500 Dong Chuan Road, Shanghai, 200241, China
| | - Liping Pan
- Institute of Eco-Chongming, 3663N. Zhongshan Road, Shanghai, 200062, China
| | - Xiaohan Zhang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, 500 Dong Chuan Road, Shanghai, 200241, China
| | - Xuechu Chen
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, 500 Dong Chuan Road, Shanghai, 200241, China; Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, 3663 N. Zhongshan Road, Shanghai, 200062, China; Institute of Eco-Chongming, 3663N. Zhongshan Road, Shanghai, 200062, China.
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5
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Malherbe H, Le Maitre D, Le Roux J, Pauleit S, Lorz C. A Simplified Method to Assess the Impact of Sediment and Nutrient Inputs on River Water Quality in Two Regions of the Southern Coast of South Africa. Environ Manage 2019; 63:658-672. [PMID: 30778651 DOI: 10.1007/s00267-019-01147-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 02/04/2019] [Indexed: 06/09/2023]
Abstract
Many rivers in the southern coastal region of the Western Cape Province, South Africa, are known to be in a poor state. Since the 1990s, the river water quality of this coastal region has been affected by increasing populations and by intensifying land use activities. Simplified risk assessment approaches are critical to identify in a timely manner areas where land use activities may impact water quality, particularly for regions with limited data. For this study, a simple assessment approach to estimate the impacts of land use activities on river water quality was improved by incorporating landscape potentials that take into account environmental factors. The methods were applied to two regions experiencing intensive land use along the southern coast. The findings indicate that the incorporation of the landscape potentials, (i) the landscape sediment generation potential and (ii) the diffuse nitrate potential, to estimate the impacts of sediment and nutrient inputs on river water quality need to be considered. Agricultural activities and informal settlements contribute to the increasing sediment and nutrient inputs of the river reaches. Areas with high proportions of river reaches at increasing pollution risk need to be managed on a large scale to ensure that all the potentially affected sub-catchments are included.
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Affiliation(s)
- Hanlie Malherbe
- Department of Forestry, Hochschule Weihenstephan-Triesdorf, University of Applied Sciences, Hans-Carl-von-Carlowitz-Platz 3, Freising, 85354, Germany.
- Chair for Strategic Landscape Planning and Management, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Emil-Ramann-Str. 6, Freising, 85354, Germany.
| | - David Le Maitre
- Natural Resources and the Environment, Council for Scientific and Industrial Research, PO Box 320, Stellenbosch, 7599, South Africa
| | - Jay Le Roux
- Department of Geography, University of the Free State, 205 Nelson Mandela Dr, Park West, Bloemfontein, 9301, South Africa
| | - Stephan Pauleit
- Chair for Strategic Landscape Planning and Management, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Emil-Ramann-Str. 6, Freising, 85354, Germany
| | - Carsten Lorz
- Department of Forestry, Hochschule Weihenstephan-Triesdorf, University of Applied Sciences, Hans-Carl-von-Carlowitz-Platz 3, Freising, 85354, Germany
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6
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Levi L, Cvetkovic V, Destouni G. Data-driven analysis of nutrient inputs and transfers through nested catchments. Sci Total Environ 2018; 610-611:482-494. [PMID: 28820979 DOI: 10.1016/j.scitotenv.2017.08.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 07/31/2017] [Accepted: 08/01/2017] [Indexed: 06/07/2023]
Abstract
A data-driven screening methodology is developed for estimating nutrient input and retention-delivery in catchments with measured water discharges and nutrient concentrations along the river network. The methodology is applied to the Sava River Catchment (SRC), a major transboundary catchment in southeast Europe, with seven monitoring stations along the main river, defining seven nested catchments and seven incremental subcatchments that are analysed and compared in this study. For the relatively large nested catchments (>40,000km2), characteristic regional values emerge for nutrient input per unit area of around 30T/yr/km2 for dissolved inorganic nitrogen (DIN) and 2T/yr/km2 for total phosphorus (TP). For the smaller nested catchments and incremental subcatchments, corresponding values fluctuate and indicate hotspot areas with total nutrient inputs of 158T/yr/km2 for DIN and 13T/yr/km2 for TP. The delivered fraction of total nutrient input mass (termed delivery factor) and associated nutrient loads per area are scale-dependent, exhibiting power-law decay with increasing catchment area, with exponents of around 0.2-0.3 for DIN and 0.3-0.5 for TP. For the largest of the nested catchments in the SRC, the delivery factor is around 0.08 for DIN and 0.03 for TP. Overall, the nutrient data for nested catchments within the SRC show consistency with previously reported data for multiple nested catchments within the Baltic Sea Drainage Basin, identifying close nutrient relationships to driving hydro-climatic conditions (runoff for nutrient loads) and socio-economic conditions (population density and farmland share for nutrient concentrations).
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Affiliation(s)
- Lea Levi
- Department of Sustainable development, Environmental science and Engineering (SEED), Royal Institute of Technology (KTH), Stockholm, Sweden; Department of Physical Geography and the Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden; Department of Applied Hydraulics, Faculty of Civil Engineering, Architecture and Geodesy, University of Split, Split, Croatia.
| | - Vladimir Cvetkovic
- Department of Sustainable development, Environmental science and Engineering (SEED), Royal Institute of Technology (KTH), Stockholm, Sweden
| | - Georgia Destouni
- Department of Physical Geography and the Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden
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Botter-Carvalho ML, Carvalho PVVC, Valença APMC, Santos PJP. Estuarine macrofauna responses to continuous in situ nutrient addition on a tropical mudflat. Mar Pollut Bull 2014; 83:214-223. [PMID: 24835372 DOI: 10.1016/j.marpolbul.2014.03.049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2013] [Revised: 03/20/2014] [Accepted: 03/29/2014] [Indexed: 06/03/2023]
Abstract
A field experiment to assess the effects of continuous nutrient addition on the macrobenthic community was carried out on an estuarine mudflat on the northeast coast of Brazil. The experiment began on 5 October 2005 and ended on 8 February 2006. Macrofauna was compared at approximately four-week intervals in triplicate plots with three levels (Control - C, Low Dose - LD and High Dose - HD) of weekly fertilizer additions for 17 weeks. Inorganic fertilizer (N-P-K) was applied on nine randomly defined quadrangular plots (4m(2) each). All measurements were calculated from species abundances. Multivariate analyses as well as the univariate indices (richness, abundance and Shannon-Wiener index) showed statistically significant differences between the enriched and control areas during the period of the experiment. The expected gradual response based on the succession model of Pearson and Rosenberg was not observed. The nutrient doses used were high enough to cause severe decreases in abundance, richness and evenness, and an increase in dominance.
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Affiliation(s)
- Mônica L Botter-Carvalho
- Universidade Federal Rural de Pernambuco, Av. Dom Manoel de Medeiros s/n, Dois Irmãos, 52171-900 Recife, PE, Brazil.
| | - Paulo V V C Carvalho
- Petrobras Transporte S/A, Rua Antônio Lumack do Monte, 96, 4° andar, 51020-905 Recife, PE, Brazil
| | - Ana Paula M C Valença
- Universidade Federal de Pernambuco, Cidade Universitária, Av. Prof. Moraes Rêgo s/n, 50640-920 Recife, PE, Brazil
| | - Paulo J P Santos
- Universidade Federal de Pernambuco, Cidade Universitária, Av. Prof. Moraes Rêgo s/n, 50640-920 Recife, PE, Brazil
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