Controlling blooms of Planktothrix rubescens by optimized metalimnetic water withdrawal: a modelling study on adaptive reservoir operation DOI Creative Commons
Chenxi Mi, David P. Hamilton, Marieke A. Frassl

и другие.

Environmental Sciences Europe, Год журнала: 2022, Номер 34(1)

Опубликована: Окт. 15, 2022

Abstract Background Aggregations of cyanobacteria in lakes and reservoirs are commonly associated with surface blooms, but may also occur the metalimnion as subsurface or deep chlorophyll maxima. Metalimnetic blooms great concern when potentially toxic species, such Planktothrix rubescens, involved. P. rubescens have apparently increased frequency severity recent years, so there is a strong need to identify reservoir management options control it. We hypothesized that can be suppressed using selective withdrawal maximize its export from reservoir. expect altering light climate affect dynamics this species. tested our hypothesis Rappbode Reservoir (the largest drinking water Germany) by establishing series scenarios based on calibrated quality model (CE-QUAL-W2). Results The novel strategy, which withdrawn certain depth below within instead at fixed elevation relative dam wall, significantly reduced biomass According simulation results, we defined an optimal volume approximately 10 million m 3 (10% volume) during bloom phase. results illustrated growth most effectively if metalimnetic applied early stage rapid growth, i.e., before occurs. In addition, study showed gradually decreased increasing extinction nearly disappeared coefficient exceeded 0.55 −1 . Conclusions Our indicates rise offset well reducing intensity beneath surface. Considering widespread occurrence stratified worldwide, believe will helpful for scientists managers working other bodies minimize negative impacts harmful cyanobacteria. serve transferable tool explore local standing waters.

Язык: Английский

Reservoir water quality deterioration due to deforestation emphasizes the indirect effects of global change DOI
Xiangzhen Kong, Salman Ghaffar, Maria Determann

и другие.

Water Research, Год журнала: 2022, Номер 221, С. 118721 - 118721

Опубликована: Июнь 7, 2022

Язык: Английский

Процитировано

69
Effect of thermal stratification on denitrifying bacterial community in a deep drinking water reservoir DOI
Haihan Zhang, Kaiwen Liu, Tinglin Huang

и другие.

Journal of Hydrology, Год журнала: 2021, Номер 596, С. 126090 - 126090

Опубликована: Фев. 21, 2021

Язык: Английский

Процитировано

49
Oxygen evolution and its drivers in a stratified reservoir: A supply-side perspective for informing hypoxia alleviation strategies DOI

Yuanning Zhang,

Xueping Gao,

Bowen Sun

и другие.

Water Research, Год журнала: 2024, Номер 257, С. 121694 - 121694

Опубликована: Апрель 29, 2024

Язык: Английский

Процитировано

7
Fifteen Years of Integrated Terrestrial Environmental Observatories (TERENO) in Germany: Functions, Services, and Lessons Learned DOI Creative Commons
Steffen Zacharias, Henry W. Loescher, Heye Bogena

и другие.

Earth s Future, Год журнала: 2024, Номер 12(6)

Опубликована: Июнь 1, 2024

Abstract The need to develop and provide integrated observation systems better understand manage global regional environmental change is one of the major challenges facing Earth system science today. In 2008, German Helmholtz Association took up this challenge launched research infrastructure TERrestrial ENvironmental Observatories (TERENO). aim TERENO establishment maintenance a network observatories as basis for an interdisciplinary long‐term program investigate effects on terrestrial ecosystems their socio‐economic consequences. State‐of‐the‐art methods from field monitoring, geophysics, remote sensing, modeling are used record analyze states fluxes in different disciplines groundwater through vadose zone, surface water, biosphere, lower atmosphere. Over past 15 years we have collectively gained experience operating observing network, thereby overcoming unexpected operational institutional challenges, exceeding expectations, facilitating new research. Today, key pillar forecasting Germany, information hub practitioners policy stakeholders agriculture, forestry, water management at national levels, nucleus international collaboration, academic training scientific outreach, important anchor large‐scale experiments, trigger methodological innovation technological progress. This article describes TERENO's services functions, presents main lessons learned 15‐year effort, emphasizes continue monitoring programmes future.

Язык: Английский

Процитировано

7
Effects of dimensionality on the performance of hydrodynamic models for stratified lakes and reservoirs DOI Creative Commons
Mayra Ishikawa, Wendy González,

Orides Golyjeswski

и другие.

Geoscientific model development, Год журнала: 2022, Номер 15(5), С. 2197 - 2220

Опубликована: Март 16, 2022

Abstract. Numerical models are an important tool for simulating temperature, hydrodynamics, and water quality in lakes reservoirs. Existing differ dimensionality by considering spatial variations of simulated parameters (e.g., flow velocity temperature) one (1D), two (2D) or three (3D) dimensions. The different approaches based on levels simplification the description hydrodynamic processes result demands computational power. aim this study is to compare with dimensionalities analyze differences between model results relation simplifications. We simulations thermal stratification, substance transport density currents a medium-sized drinking-water reservoir subtropical zone, using widely used open-source models: GLM CE-QUAL-W2 Delft3D (3D). were operated identical initial boundary conditions over 1-year period. Their performance was assessed comparing measurements turbulence. Our show that all capable seasonal changes temperature stratification. Flow velocities, only available 2D 3D approaches, more challenging reproduce, but showed closer agreement observations. With increasing dimensionality, also increased terms error, correlation variance. None provided good observations mixed layer depth, which affects spreading inflowing as build outputs models.

Язык: Английский

Процитировано

26
Ensemble of models shows coherent response of a reservoir’s stratification and ice cover to climate warming DOI Creative Commons
Johannes Feldbauer, Robert Ladwig, Jorrit P. Mesman

и другие.

Aquatic Sciences, Год журнала: 2022, Номер 84(4)

Опубликована: Авг. 24, 2022

Abstract Water temperature, ice cover, and lake stratification are important physical properties of lakes reservoirs that control mixing as well bio-geo-chemical processes thus influence the water quality. We used an ensemble vertical one-dimensional hydrodynamic models driven with regional climate projections to calculate stratification, cover under A1B emission scenario for German drinking reservoir Lichtenberg. analysis variance method estimate contributions considered sources uncertainty on output. For all simulated variables, epistemic uncertainty, which is related model structure, dominant source throughout simulation period. Nonetheless, calculated trends coherent among five in line historical observations. The predicts increase surface temperature 0.34 K per decade, a lengthening summer 3.2 days decreased probabilities occurrence winter inverse by 2100. These expected changes likely quality reservoir. Similar be other comparable regions.

Язык: Английский

Процитировано

24
Data assimilation experiments inform monitoring needs for near‐term ecological forecasts in a eutrophic reservoir DOI Creative Commons
Heather L. Wander, R. Quinn Thomas, Tadhg N. Moore

и другие.

Ecosphere, Год журнала: 2024, Номер 15(2)

Опубликована: Фев. 1, 2024

Abstract Ecosystems around the globe are experiencing changes in both magnitude and fluctuations of environmental conditions due to land use climate change. In response, ecologists increasingly using near‐term, iterative ecological forecasts predict how ecosystems will change future. To date, many forecasting systems have been developed high temporal frequency (minute hourly resolution) data streams for assimilation. However, this approach may be cost‐prohibitive or impossible variables that lack high‐frequency sensors latency (i.e., a delay before available modeling after collection). explore effects assimilation on forecast skill, we water temperature eutrophic drinking reservoir conducted experiments by selectively withholding observations examine effect availability accuracy. We used situ sensors, manually collected data, calibrated quality ecosystem model driven forecasted weather generate future Forecasting Lake Reservoir (FLARE), an open source system. tested daily, weekly, fortnightly, monthly skill 1‐ 35‐day‐ahead forecasts. found varied depending season, horizon, depth, frequency, but overall performance was high, with mean 1‐day‐ahead root square error (RMSE) 0.81°C, 7‐day RMSE 1.15°C, 35‐day 1.94°C. Aggregated across year, daily yielded most skillful at 7‐day‐ahead horizons, weekly resulted 8‐ horizons. Within consistently outperformed 8‐day horizon during mixed spring/autumn periods 5‐ 14‐day‐ahead horizons summer‐stratified period, depth. Our results suggest lower weekly) adequate developing accurate some applications, further enabling development broadly without sensor data.

Язык: Английский

Процитировано

6
Future projections of thermal regimes and mixing characteristics in a monomictic reservoir under climate change DOI
Haoyu Wang, Yun Deng,

Yanjing Yang

и другие.

The Science of The Total Environment, Год журнала: 2023, Номер 906, С. 167527 - 167527

Опубликована: Окт. 1, 2023

Язык: Английский

Процитировано

13
Interacting impacts of hydrological changes and air temperature warming on lake temperatures highlight the potential for adaptive management DOI Creative Commons
Freya Olsson, Eleanor B. Mackay, Bryan M. Spears

и другие.

AMBIO, Год журнала: 2024, Номер unknown

Опубликована: Май 25, 2024

Abstract Globally, climate warming is increasing air temperatures and changing river flows, but few studies have explicitly considered the consequences for lake of these dual effects, or potential to manage inflows mitigate impacts. Using a one-dimensional model, we tested sensitivity separate interacting effects changes in temperature inflow on small, short-residence time (annual average ≈ 20 days), temperate lake. Reducing by 70% increased summer surface 1.0–1.2 °C water column stability 11–19%, equivalent effect 1.2 warming. Conversely, similar increases could result cooling, sufficient 0.75 rise, more than 1.1 if does not rise. We discuss how altering volume be added suite adaptation measures lakes.

Язык: Английский

Процитировано

5
Temperatures and hypolimnetic oxygen in German lakes: Observations, future trends and adaptation potential DOI Creative Commons
Robert Schwefel, Lipa Nkwalale,

Sylvia Jordan

и другие.

AMBIO, Год журнала: 2024, Номер unknown

Опубликована: Июль 5, 2024

Abstract We investigated trends in temperature, stratification, and hypolimnetic oxygen concentration of German lakes under climate change using observational data hydrodynamic modelling. Observations from 46 revealed that annually averaged surface temperatures increased by + 0.5 °C between 1990 2020 while bottom remained almost constant. Modelling 12 predicted further increases 0.3 °C/decade until the year 2099 most pessimistic emission scenario RCP 8.5 (RCP 4.5: 0.18 °C/decade; 2.6: 0.04 °C/decade). Again, much less summer stratification extended up to 38 days. Using a simplified model, we showed concentrations decreased 0.7–1.9 mg L −1 response period. However, model runs assuming lower productivity (e. g. through nutrient reduction) resulted even scenario. Our results suggest negative effects on budget can be efficiently mitigated control.

Язык: Английский

Процитировано

5