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Identification of relevant low flow in hydrologically unexamined rivers
1998
Petkovic, T. (Savezni hidrometeoroloski zavod, Beograd (Yugoslavia))
The paper presents some procedures for identification of low flow required for taking preventive measures in the rivers with no comprehensive hydrological observations. Besides using time - space parameters, temparery or simultaneous hydrometric observations in the observed rivers are also recommended. The paper concludes with the presentation of relevant low flow calculation results for one river in Zlatibor region (Serbia, Yugoslavia), which has not been examined so far.
Afficher plus [+] Moins [-]RECOTOX, a French initiative in ecotoxicology-toxicology to monitor, understand and mitigate the ecotoxicological impacts of pollutants in socioagroecosystems
2018
Mougin, Christian | Gouy, Véronique | Bretagnolle, Vincent | Berthou, Julie | Andrieux, Patrick | Ansart, Patrick | Benoit, Marc | Coeurdassier, Michael | Comte, Irina | Dagès, Cécile | Denaix, Laurence | Dousset, Sylvie | Ducreux, Laure | Gaba, Sabrina | Gilbert, Daniel | Imfeld, Gwenaël | Liger, Lucie | Molenat, Jérôme | Payraudeau, Sylvain | Samouëlian, Anatja | Schott, Céline | Tallec, Gaëlle | Vivien, Emma | Voltz, Marc | Ecologie fonctionnelle et écotoxicologie des agroécosystèmes (ECOSYS) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech | RiverLy (UR Riverly) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC) ; Institut National de la Recherche Agronomique (INRA)-La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS) | Agrosystèmes tropicaux (ASTRO) ; Institut National de la Recherche Agronomique (INRA) | Hydrosystèmes continentaux anthropisés : ressources, risques, restauration (UR HYCAR) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Agro-Systèmes Territoires Ressources Mirecourt (ASTER Mirecourt) ; Institut National de la Recherche Agronomique (INRA) | Laboratoire Chrono-environnement (UMR 6249) (LCE) ; Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC) ; Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC) | Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad) | Laboratoire d'étude des Interactions Sol - Agrosystème - Hydrosystème (UMR LISAH) ; Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro) | Interactions Sol Plante Atmosphère (UMR ISPA) ; Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro) | Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC) ; Institut Ecologie et Environnement (INEE) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Terre et Environnement de Lorraine (OTELo) ; Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS) | Bureau de Recherches Géologiques et Minières (BRGM) (BRGM) | Laboratoire de Biologie et Ecophysiologie ; Université de Franche-Comté (UFC) ; Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC) | Laboratoire d'Hydrologie et de Géochimie de Strasbourg (LHyGeS) ; Ecole et Observatoire des Sciences de la Terre (EOST) ; Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École Nationale du Génie de l'Eau et de l'Environnement de Strasbourg (ENGEES)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
[Departement_IRSTEA]Eaux [TR1_IRSTEA]ARCEAU [ADD1_IRSTEA]Hydrosystèmes et risques naturels | International audience | RECOTOX is a cross-cutting initiative promoting an integrated research to respond to the challenges of monitoring, understanding, and mitigating environmental and health impacts of pesticides in agroecosystems. The added value of RECOTOX is to develop a common culture around spatial ecotoxicology including the whole chain of pressure-exposure-impact, while strengthening an integrated network of in natura specifically equipped sites. In particular, it promotes transversal approaches at relevant socioecological system scales, to capitalize knowledge, expertise, and ongoing research in ecotoxicology and, to a lesser extent, environmental toxicology. Thus, it will open existing research infrastructures in environmental sciences to research programs in ecotoxicology of pesticides.
Afficher plus [+] Moins [-]RECOTOX, a French initiative in ecotoxicology-toxicology to monitor, understand and mitigate the ecotoxicological impacts of pollutants in socioagroecosystems
2018
Mougin, Christian | Gouy, Véronique | Bretagnolle, Vincent | Berthou, Julie | Andrieux, Patrick | Ansart, Patrick | Benoit, Marc | Coeurdassier, Michael | Comte, Irina | Dagès, Cécile | Denaix, Laurence | Dousset, Sylvie | Ducreux, Laure | Gaba, Sabrina | Gilbert, Daniel | Imfeld, Gwenaël | Liger, Lucie | Molenat, Jérôme | Payraudeau, Sylvain | Samouëlian, Anatja | Schott, Céline | Tallec, Gaëlle | Vivien, Emma | Voltz, Marc | Ecologie fonctionnelle et écotoxicologie des agroécosystèmes (ECOSYS) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech | RiverLy - Fonctionnement des hydrosystèmes ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC) ; Institut National de la Recherche Agronomique (INRA)-La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS) | Agrosystèmes tropicaux (ASTRO) ; Institut National de la Recherche Agronomique (INRA) | Hydrosystèmes continentaux anthropisés : ressources, risques, restauration (UR HYCAR) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Agro-Systèmes Territoires Ressources Mirecourt (ASTER Mirecourt) ; Institut National de la Recherche Agronomique (INRA) | Laboratoire Chrono-environnement (UMR 6249) (LCE) ; Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC) ; Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC) | Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad) | Laboratoire d'étude des Interactions Sol - Agrosystème - Hydrosystème (UMR LISAH) ; Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro) | Interactions Sol Plante Atmosphère (UMR ISPA) ; Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro) | Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC) ; Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Terre et Environnement de Lorraine (OTELo) ; Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS) | Bureau de Recherches Géologiques et Minières (BRGM) | Laboratoire de Biologie et Ecophysiologie ; Université de Franche-Comté (UFC) ; Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC) | Laboratoire d'Hydrologie et de Géochimie de Strasbourg (LHyGeS) ; Ecole et Observatoire des Sciences de la Terre (EOST) ; Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École Nationale du Génie de l'Eau et de l'Environnement de Strasbourg (ENGEES)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
[Departement_IRSTEA]Eaux [TR1_IRSTEA]ARCEAU [ADD1_IRSTEA]Hydrosystèmes et risques naturels | International audience | RECOTOX is a cross-cutting initiative promoting an integrated research to respond to the challenges of monitoring, understanding, and mitigating environmental and health impacts of pesticides in agroecosystems. The added value of RECOTOX is to develop a common culture around spatial ecotoxicology including the whole chain of pressure-exposure-impact, while strengthening an integrated network of in natura specifically equipped sites. In particular, it promotes transversal approaches at relevant socioecological system scales, to capitalize knowledge, expertise, and ongoing research in ecotoxicology and, to a lesser extent, environmental toxicology. Thus, it will open existing research infrastructures in environmental sciences to research programs in ecotoxicology of pesticides.
Afficher plus [+] Moins [-]Metal(loid) pollution, not urbanisation nor parasites predicts low body condition in a wetland bioindicator snake
2022
Lettoof, Damian C. | Cornelis, Jari | Jolly, Christopher J. | Aubret, Fabien | Gagnon, Marthe Monique | Hyndman, Timothy H. | Barton, Diane P. | Bateman, Philip W.
Urban ecosystems and remnant habitat 'islands' therein, provide important strongholds for many wildlife species including those of conservation significance. However, the persistence of these habitats can be undermined if their structure and function are too severely disrupted. Urban wetlands, specifically, are usually degraded by a monoculture of invasive vegetation, disrupted hydrology, and chronic-contamination from a suite of anthropogenic pollutants. Top predators—as bioindicators—can be used to assess and monitor the health of these ecosystems. We measured eight health parameters (e.g., parasites, wounds and scars, tail loss and body condition) in a wetland top predator, the western tiger snake, Notechis scutatus occidentalis. For three years, snakes were sampled across four wetlands along an urban gradient. For each site, we used GIS software to measure the area of different landscapes and calculate an urbanisation–landscape score. Previously published research on snake contamination informed our calculations of a metal-pollution index for each site. We used generalised linear mixed models to assess the relationship between all health parameters and site variables. We found the metal-pollution index to have the most significant association with poor body condition. Although parasitism, tail loss and wounds differed among sites, none of these parameters influenced body condition. Additionally, the suite of health parameters suggested differing health status among sites; however, our measure of contemporary landscape urbanisation was never a significant predictor variable. Our results suggest that the health of wetland predators surrounding a rapidly growing city may be offset by higher levels of environmental pollution.
Afficher plus [+] Moins [-]Multimedia distribution of polycyclic aromatic hydrocarbons in the Wang Lake Wetland, China
2022
Shi, Changhe | Qu, Chengkai | Sun, Wen | Zhou, Jingzhe | Zhang, Jiawei | Cao, Yu | Zhang, Yuan | Guo, J. (Jiahua) | Zhang, Jiaquan | Qi, Shihua
The Wang Lake Wetland is a highly valued area that is protected due to its high biodiversity. The wetland has a complicated hydrological regime and is subject to frequent human disturbance. We hypothesize that fluctuating hydrology and human activities have varied contributions to the temporal and spatial variations of polycyclic aromatic hydrocarbons (PAHs) in the wetland. Soil (SS), sediment (SD), and water, to acquire dissolved phase (DP) and suspended particulate matter (SPM), samples were collected from eight locations during low- and high-flow periods to elucidate multimedia phase distribution and transport of PAHs. Following the onset of the rainy season, the concentration of SPM-associated PAHs increased significantly, while the DP PAHs remained stable. Individual PAH ratios showed that, although pyrogenic sources are common, petrogenic derived compounds are the main source of PAHs in the Wang Lake Wetland. During the high-flow period, the empirical values for logarithms of the organic carbon-normalized partition coefficients (log KOC) of individual PAH-congeners were lower than the corresponding field-observed log KOC values from the SPM-DP and SD-DP systems, reflecting the complexity in evaluating multi-phase PAH partitioning. During the high-flow period, temperature-driven changes may have changed the sediment from a sink to a source for some high molecular weight PAHs. It was determined that human activities governed the PAH loading in the low-flow period, whereas during high-flow conditions, increased rainfall, higher temperatures, and fishery activity are the main factors controlling PAH input to the Wang Lake Wetland.
Afficher plus [+] Moins [-]Untangling radiocesium dynamics of forest-stream ecosystems: A review of Fukushima studies in the decade after the accident
2021
Sakai, Masaru | Tsuji, Hideki | Ishii, Yumiko | Ozaki, Hirokazu | Takechi, Seiichi | Jo, Jaeick | Tamaoki, Masanori | Hayashi, Seiji | Gomi, Takashi
Forest-stream ecosystems are widespread and biodiverse terrestrial landscapes with physical and social connections to downstream human activities. After radiocesium is introduced into these ecosystems, various material flows cause its accumulation or dispersal. We review studies conducted in the decade after the Fukushima nuclear accident to clarify the mechanisms of radiocesium transfer within ecosystems and to downstream areas through biological, hydrological, and geomorphological processes. After its introduction, radiocesium is heavily deposited in the organic soil layer, leading to persistent circulation due to biological activities in soils. Some radiocesium in soils, litter, and organisms is transported to stream ecosystems, forming contamination spots in depositional habitats. While reservoir dams function as effective traps, radiocesium leaching from sediments is a continual phenomenon causing re-contamination downstream. Integration of data regarding radiocesium dynamics and contamination sites, as proposed here, is essential for contamination management in societies depending on nuclear power to address the climate crisis.
Afficher plus [+] Moins [-]Multidecadal water quality deterioration in the largest freshwater lake in China (Poyang Lake): Implications on eutrophication management
2020
Li, Bing | Yang, Guishan | Wan, Rongrong
Poyang Lake is the largest freshwater lake in China and a globally important wetland with various functions. Exploring the multidecadal trend of water quality and hydroclimatic conditions is important for understanding the adaption of the lake system under the pressure from multiple anthropogenic and meteorological stressors. The present study applied the Mann–Kendall trend analysis and Pettitt test to detect the trend and breakpoints of hydroclimatic, and water quality parameters (from the 1980s to 2018) and the trend of monthly–seasonal ammonia (NH₄-N) and total phosphorus (TP)concentrations (from 2002 to 2018) in Poyang Lake. Results showed that Poyang Lake had undergone a highly significant warming trend from 1980 to 2018, with a warming rate of 0.44 °C/decade in terms of annual daily mean air temperature. The wind speed and water level of the lake presented a highly significant decreasing trend, whereas no notable trend was detected for precipitation variations. The annual mean total nitrogen (TN), NH₄-N, TP, and permanganate index (CODMₙ) concentrations showed significant upward trends from the 1980s to 2018. Remarkable abrupt shifts were detected for TN, NH₄-N, and CODMₙ in around 2003. They were in accordance with the water level breakpoint of the lake, thus implying the important role of hydrological conditions in water quality variations in floodplain lakes. A significant increasing trend has been detected for Chl-a variations during wet season from 2008 to 2018, which could be attributed to the increasing trend of nutrient concentration during the nutrient-limited phase of Poyang Lake. These hydroclimatic and water quality trends suggest a high risk of increasing phytoplankton growth in Poyang Lake. This study thus emphasizes the need for adaptive lake eutrophication management for floodplain lakes, particularly the consideration of the strong trade-off and synergies between hydroclimatic conditions and water quality variations.
Afficher plus [+] Moins [-]Contrasting temporal dynamics of dissolved and colloidal trace metals in the Pearl River Estuary
2020
Xie, Minwei | Wang, Wen-Xiong
Metal contamination in the Pearl River Estuary (PRE) is persistent-, yet a comprehensive understanding of distribution and behavior of metals in surface water of this large, multi-source estuary is still lacking. In the present study, water samples from 24 sites spanning the whole estuary during the dry and wet season were collected and fractioned. Trace metal concentrations in samples were then determined following a preconcentration technique using Nobias Chelate-PA1 resin. Distribution of trace metals exhibited variability along and across estuary, as a result of estuarine mixing, external metal loadings, addition and removal. Behavior of metals was contrasting between the dry and wet seasons, exhibiting metal-specific intercorrelations and dynamics. Colloidal metals (Mn, Ni and Cd) were primarily present in upper estuary and areas affected by external contaminant loading. Colloidal Cu was the only metal that was ubiquitous in the estuary in both seasons. It showed a high affinity for small-size organic colloids (likely fulvic acid) during the dry season. Overall, the present study demonstrated the multi-source character of the PRE and that the behavior of trace metals was controlled by the coupling of hydrologic and geochemical processes, with anthropogenic perturbations.
Afficher plus [+] Moins [-]The role of hydrological conditions for riverine Hg species transport in the Idrija mining area
2019
Baptista-Salazar, Carluvy | Biester, Harald
Estimation of mercury (Hg) species fluxes in Hg contaminated rivers is crucial to predict Hg methylation in connected sediment sinks. Cinnabar (HgS) was mined and roasted for ∼500 years in the Idrija mining area, Slovenia, which is drained by the Idrijca River to the Gulf of Trieste (GT), Italy. Mining residues dumped into the Idrijca River caused high proportions of cinnabar in sediments, whereas soils containing high proportions of natural organic matter bound to Hg (NOM-Hg) are attributed to atmospheric Hg deposition. Previous calculations of Hg fluxes have been based on the erosion of cinnabar only, and neglected transport of NOM-Hg derived from soil. Here, we estimated NOM-Hg and cinnabar fluxes in the Idrijca River and evaluated the extent of variability under changing hydrological conditions. We estimated the discharge of NOM-Hg by Idrijca's tributaries and the importance of NOM-Hg fluxes for Hg methylation in the GT. Mass balance calculations reveal that approximately 11.2 Mg y⁻¹ of NOM-Hg and 38.9 Mg y⁻¹ of cinnabar are transported by the Idrijca River to the GT under median-flow conditions. In the past 520 years, a total of 53,000 tons of Hg have been released from the Idrija mining area, of which ∼32,000 tons were NOM-Hg. Under low-flow conditions, Idrijca's tributaries deliver more than 1280 kg y⁻¹ of NOM-Hg. This study highlights the importance of Hg species analyses and their flux calculations to estimate risks of biological Hg uptake in sedimentary Hg sinks connected to Hg mining areas.
Afficher plus [+] Moins [-]Nitrate loads in sub-tropical headwater streams driven by intensive horticulture
2018
White, Shane A. | Santos, Isaac R. | Hessey, Samantha
Nitrogen runoff from fertiliser intensive land uses has become an issue worldwide, contributing to algal blooms, hypoxic waters and aquatic biodiversity losses. This study assessed potential nutrient pollution from blueberry farms in subtropical Australia and examines whether nutrient loads were driven by groundwater discharge and/or surface water runoff. Streams downstream of eight blueberry farms were compared to eight nearby control sites without any blueberry activity. In the 90 day sample period, there were three rain events >90 mm day⁻¹ that produced runoff sufficient to create flooding. Overall, the results revealed a clear link between blueberry farming and nitrogen runoff in headwater streams. While NOX (nitrate + nitrite) was the dominant nitrogen species downstream of blueberry farms, dissolved organic nitrogen (DON) was the dominant species in control sites. The concentrations and loads of NOₓ were one order of magnitude lower in the eight non-blueberry (6.3 ± 2.0 μmol L⁻¹; 1.6 ± 1.2 kg N-NOX ha⁻¹ yr⁻¹) than the eight blueberry (56.9 ± 14.2 μmol L⁻¹; 21.8 ± 8.0 kg N-NOX ha⁻¹ yr⁻¹) sites. NOX concentrations and loads were highest following rain events. Radon (²²²Rn, a natural groundwater tracer) observations and low nitrogen concentration in groundwater samples further suggest that surface runoff dominates the delivery of nitrogen to the creeks investigated. NOX concentrations and loads in creeks correlated with blueberry farm density. At >15% of blueberry land use in a catchment, there was a detectable influence in NOX concentrations and loads in the headwater streams. Assuming that our load estimates can be up-scaled to annual nitrogen creek exports, and that local farmers use the recommended amount of fertiliser (121 kg N ha⁻¹ yr⁻¹), between 18 and 25% of the used fertiliser was lost to the creeks. This implies that there are opportunities for decreasing the use of fertilisers in this catchment and managing any nitrogen that escapes to the creeks.
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