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35 results on '"Landis, J.-D."'

2. Nearing final design of the ITER EC H&CD Upper Launcher

Author

Strauss, D., Aiello, G., Bertizzolo, R., Bruschi, A., Casal, N., Chavan, R., Farina, D., Figini, L., Gagliardi, M., Goodman, T.P., Grossetti, G., Heemskerk, C., Henderson, M.A., Kasparek, W., Koning, J., Landis, J.-D., Leichtle, D., Meier, A., Moro, A., Nowak, S., Pacheco, J., Platania, P., Plaum, B., Poli, E., Ramseyer, F., Ronden, D., Saibene, G., Más-Sanchez, A., Santos Silva, P., Sauter, O., Scherer, T., Schreck, S., Sozzi, C., Spaeh, P., Vagnoni, M., Vaccaro, A., and Weinhorst, B.

Published
2019
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4. Gas puff imaging on the TCV tokamak.

Author

Offeddu, N., Wüthrich, C., Han, W., Theiler, C., Golfinopoulos, T., Terry, J. L., Marmar, E., Galperti, C., Andrebe, Y., Duval, B. P., Bertizzolo, R., Clement, A., Février, O., Elaian, H., Gönczy, D., and Landis, J. D.

Subjects
FUSION reactor divertors, TOKAMAKS, AVALANCHE photodiodes, PLASMA dynamics, PLASMA turbulence, GAS injection
Abstract

We present the design and operation of a suite of Gas Puff Imaging (GPI) diagnostic systems installed on the Tokamak à Configuration Variable (TCV) for the study of turbulence in the plasma edge and Scrape-Off-Layer (SOL). These systems provide the unique ability to simultaneously collect poloidal 2D images of plasma dynamics at the outboard midplane, around the X-point, in both the High-Field Side (HFS) and Low-Field Side (LFS) SOL, and in the divertor region. We describe and characterize an innovative control system for deuterium and helium gas injection, which is becoming the default standard for the other gas injections at TCV. Extensive pre-design studies and the different detection systems are presented, including an array of avalanche photodiodes and a high-speed CMOS camera. First results with spatial and time resolutions of up to ≈ 2 mm and 0.5 µs, respectively, are described, and future upgrades of the GPI diagnostics for TCV are discussed. [ABSTRACT FROM AUTHOR]

Published
2022
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6. Conceptual design of the ECH upper launcher system for ITER

Author

Heidinger, R., Bertizzolo, R., Bruschi, A., Chavan, R., Cirant, S., Collazos, A., de Baar, M., Elzendoorn, B., Farina, D., Fischer, U., Gafert, J., Gandini, F., Gantenbein, G., Goede, A., Goodman, T., Hailfinger, G., Henderson, M., Kasparek, W., Kleefeldt, K., Landis, J.-D., Meier, A., Moro, A., Platania, P., Poli, E., Ramponi, G., Saibene, G., Sanchez, F., Sauter, O., Scherer, T., Serikov, A., Shidara, H., Sozzi, C., Spaeh, P., Strauss, D., Udintsev, V.S., Vaccaro, A., Zohm, H., and Zucca, C.

Published
2009
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7. Progress on the ITER H&CD EC upper launcher steering-mirror control system

Author

Collazos, A., Bertizzolo, R., Chavan, R., Dolizy, F., Felici, F., Goodman, T.P., Henderson, M.A., Landis, J.-D., and Sanchez, F.

Subjects
Control systems -- Research, Magnetic flux -- Measurement, Magnetohydrodynamics -- Analysis, Nuclear reactors -- Innovations, Technical institutes -- Research, Business, Chemistry, Electronics, Electronics and electrical industries, International Thermonuclear Experimental Reactor -- Research
Published
2010

10. Accuracy of methods for reporting inorganic element concentrations and radioactivity in oil and gas wastewaters from the Appalachian Basin, U.S. based on an inter-laboratory comparison

Author

Tasker, T. L., primary, Burgos, W. D., additional, Ajemigbitse, M. A., additional, Lauer, N. E., additional, Gusa, A. V., additional, Kuatbek, M., additional, May, D., additional, Landis, J. D., additional, Alessi, D. S., additional, Johnsen, A. M., additional, Kaste, J. M., additional, Headrick, K. L., additional, Wilke, F. D. H., additional, McNeal, M., additional, Engle, M., additional, Jubb, A. M., additional, Vidic, R. D., additional, Vengosh, A., additional, and Warner, N. R., additional

Published
2019
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11. An overview of the ITER electron cyclotron H&CD system

Author

Massachusetts Institute of Technology. Department of Physics, Massachusetts Institute of Technology. Plasma Science and Fusion Center, Temkin, Richard J., Temkin, Richard J, Henderson, M., Albajar, F., Alberti, S., Baruah, U., Bigelow, T., Becket, B., Bertizzolo, R., Bonicelli, T., Bruschi, A., Caughman, J., Chavan, R., Cirant, S., Collazos, A., Darbos, C., de Baar, M., Denisov, G., Farina, D., Gandini, F., Gassman, T., Goodman, T. P., Heidinger, R., Hogge, J. P., Jean, O., Kajiwara, K., Kasparek, W., Kasugai, A., Kern, S., Kobayashi, N., Landis, J. D., Moro, A., Nazare, C., Oda, J., Paganakis, I., Platania, P., Plaum, B., Poli, E., Porte, L., Pioscyzyk, B., Ramponi, G., Rao, S. L., Rasmussen, D., Ronden, D., Saibene, G., Sakamoto, K., Sanchez, F., Scherer, T., Shapiro, M., Sozzi, C., Spaeh, P., Straus, D., Sauter, O., Takahashi, K., Tanga, A., Thumm, M., Tran, M. Q., Zohm, H., Zucca, C., Massachusetts Institute of Technology. Department of Physics, Massachusetts Institute of Technology. Plasma Science and Fusion Center, Temkin, Richard J., Temkin, Richard J, Henderson, M., Albajar, F., Alberti, S., Baruah, U., Bigelow, T., Becket, B., Bertizzolo, R., Bonicelli, T., Bruschi, A., Caughman, J., Chavan, R., Cirant, S., Collazos, A., Darbos, C., de Baar, M., Denisov, G., Farina, D., Gandini, F., Gassman, T., Goodman, T. P., Heidinger, R., Hogge, J. P., Jean, O., Kajiwara, K., Kasparek, W., Kasugai, A., Kern, S., Kobayashi, N., Landis, J. D., Moro, A., Nazare, C., Oda, J., Paganakis, I., Platania, P., Plaum, B., Poli, E., Porte, L., Pioscyzyk, B., Ramponi, G., Rao, S. L., Rasmussen, D., Ronden, D., Saibene, G., Sakamoto, K., Sanchez, F., Scherer, T., Shapiro, M., Sozzi, C., Spaeh, P., Straus, D., Sauter, O., Takahashi, K., Tanga, A., Thumm, M., Tran, M. Q., Zohm, H., and Zucca, C.

Abstract

This paper reviews the design and functionality of the 24 MW 170 GHz electron cyclotron heating and current drive system being planned for the ITER Tokamak. The sub-systems (power supplies, gyrotrons, transmission lines and launcher antennas) are described based on present day technologies, while on-going R&D provides component and sub-system testing with the possibility of increasing the reliability of the overall EC system. Modifications to the steering ranges of the launching antennas are under investigation that can improve the functional capabilities of the EC system without increasing cost and relaxing the engineering constraints.

Published
2017

12. Front steering configuration with internal optics for the ECRH ITER Upper Launcher

Author

Moro A., Alessi E., Bruschi A., Cirant S., Chavan R., Collazos A., Farina D., Henderson M. A., Landis J. D., Platania P., Poli E., Ramponi G., Saibene G., Shidara H., Sozzi C., and Udintsev V. S.

Subjects
___
Abstract

Amongst the possible improvements in the internal optics for the ECRH Upper Launcher of ITER, which is assessed and close to com-pletion, a full quasi-optical design for the launcher has been investigated and here proposed. This option is obtained with the replacement of the mitre bends with free space mirrors and can provide improvements in terms of a reduction of the power density with respect to the mitre bends case, additional flexibility and transmission efficiency, with an overall downgrading of the costs of the launcher. In this work we present the general ideas of this proposal, starting from the present Front Steering (FS) design and following a matching approach from given final beams and positions, in order to minimize impact on design.

Published
2008

13. Design Status of the ITER Upper Port Launcher

Author

Henderson, M.A., Chavan, R., Bertizzolo, R., Bruschi, A., Campbell, D., Cirant, S., Collazos, A., Danilov, I., Dolizy, F., Duron, J., Farina, D., Kleefeldt, K., Heidinger, R., Landis, J.-D., Poli, E., Ramponi, G., Saibene, G., Sanchez, F., Sauter, O., Serikov, A., and Shidar, H.

Subjects
___
Abstract

The purpose of the ITER ECRH upper port antenna (or launcher) will be to drive current locally to stabilise the NTMs (depositing ECCD inside of the island which forms on the q=3/2 or 2 rational magnetic flux surfaces) and control the sawtooth instability (deposit ECCD near the q=1 surface). The launcher should be capable of steering the focused beam deposition location across the resonant flux surface over the range in which the q=1, 3/2 and 2 surfaces are expected to be found, for the various plasma equilibria susceptible to the onset of NTMs and sawteeth. ITER's present reference design uses a front steering (FS) concept, with the moveable mirror close to the plasma. Two separate mirrors are used to decouple the focussing and steering aspects resulting in an optimized optical configuration providing a well focused beam over a large steering range. The launcher is capable of steering eight 2MW beams in all of the four allocated upper port plugs. The critical component of the FS launcher is the steering mechanism, which will be a frictionless and backlash free mechanical system based on the compliant deformation of structural components to avoid the in vessel tribological difficulties. An inert gas pressure controlled bellows system provides accurate angular positioning of the steering mirror. The entire launcher (mm-wave components) can be designed fail-safe in that if a given subsystem fails, it can be isolated and ITER can continue operation. In addition, in-situ leak testing of critical components (steering mechanism, cooling, diamond window, etc.) is envisioned to insure proper functioning and avoidance of disrupting ITER operation. Details of the FS launcher design relating to physics performance, mm-wave optical design, thermohydraulic, electromagnetic and integration of launcher components into the port plug will be discussed.

Published
2007

14. The ITER ECH FS launcher design for an optimized physics performance

Author

Henderson, M.A., Chavan, R., Bertizzolo, R., Campbell, D., Danilov, I., Dolizy, F., Farina, D., Kleefeldt, K., Heidinger, R., Landis, J.-D., Poli, E., Ramponi, G., Saibene, G., Sanchez, F., Sauter, O., Serikov, A., Shidara, H., Spaeh, P., and Zohm, H.

Published
2006

15. Progress of the ECRH Upper Launcher design for ITER

Author

Strauss, D., primary, Aiello, G., additional, Bruschi, A., additional, Chavan, R., additional, Farina, D., additional, Figini, L., additional, Gagliardi, M., additional, Garcia, V., additional, Goodman, T.P., additional, Grossetti, G., additional, Heemskerk, C., additional, Henderson, M.A., additional, Kasparek, W., additional, Krause, A., additional, Landis, J.-D., additional, Meier, A., additional, Moro, A., additional, Platania, P., additional, Plaum, B., additional, Poli, E., additional, Ronden, D., additional, Saibene, G., additional, Sanchez, F., additional, Sauter, O., additional, Scherer, T., additional, Schreck, S., additional, Serikov, A., additional, Sozzi, C., additional, Spaeh, P., additional, Vaccaro, A., additional, and Weinhorst, B., additional

Published
2014
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16. Guidelines for internal optics optimization of the ITER EC H&CD upper launcher

Author

Moro, A., primary, Bruschi, A., additional, Figini, L., additional, Chavan, R., additional, Farina, D., additional, Goodman, T. P., additional, Krause, A., additional, Henderson, M. A., additional, Landis, J. D., additional, Platania, P., additional, Saibene, G., additional, Sanchez Galan, F., additional, Sozzi, C., additional, and Toussaint, M., additional

Published
2014
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17. Preliminary design of the ITER ECH Upper Launcher

Author

Strauss, D., primary, Aiello, G., additional, Chavan, R., additional, Cirant, S., additional, deBaar, M., additional, Farina, D., additional, Gantenbein, G., additional, Goodman, T.P., additional, Henderson, M.A., additional, Kasparek, W., additional, Kleefeldt, K., additional, Landis, J.-D., additional, Meier, A., additional, Moro, A., additional, Platania, P., additional, Plaum, B., additional, Poli, E., additional, Ramponi, G., additional, Ronden, D., additional, Saibene, G., additional, Sanchez, F., additional, Sauter, O., additional, Scherer, T., additional, Schreck, S., additional, Serikov, A., additional, Sozzi, C., additional, Spaeh, P., additional, Vaccaro, A., additional, and Zohm, H., additional

Published
2013
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18. The ITER EC H&CD Upper Launcher: Maintenance concepts

Author

Ronden, D.M.S., primary, de Baar, M., additional, Chavan, R., additional, Elzendoorn, B.S.Q., additional, Grossetti, G., additional, Heemskerk, C.J.M., additional, Koning, J.F., additional, Landis, J.-D., additional, Spaeh, P., additional, and Strauss, D., additional

Published
2013
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19. Guidelines for Internal Optics Optimization of the ITER EC H&CD Upper Launcher.

Author

Moro, A., Bruschi, A., Figini, L., Chavan, R., Farina, D., Goodman, T. P., Krause, A., Henderson, M. A., Landis, J. D., Platania, P., Saibene, G., Galan, F. Sanchez, Sozzi, C., and Toussaint, M.

Subjects
TOKAMAKS, ELECTROMAGNETIC waves, ELECTRON beams, ELECTRON cyclotron resonance heating, ELECTRON cyclotron resonance sources, PLASMA devices, PLASMA stability
Abstract

The importance of localized injection of Electron Cyclotron waves to control Magneto-HydroDynamic instability is well assessed in tokamak physics and the set of four Electron Cyclotron (EC) Upper Launchers (UL) in ITER is mainly designed for this purpose. Each of the 4 ULs uses quasi-optical mirrors (shaping and planes, fixed and steerable) to redirect and focus 8 beams (in two rows, with power close to 1 MW per beam coming from the EC transmission lines) in the plasma region where the instability appears. Small beam dimensions and maximum beam superposition guarantee the necessary localization of the driven current. To achieve the goal of MHD stabilization with minimum EC power to preserve the energy confinement in the outer half of the plasma cross section, optimization of the quasi-optical design is required and a guideline of a strategy is presented. As a result of this process and following the guidelines indicated, modifications of the design (new mirrors positions, rotation axes and/or focal properties) will be proposed for the next step of an iterative process, including the mandatory compatibility check with the mechanical constraints. [ABSTRACT FROM AUTHOR]

Published
2014
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20. Preliminary design of the ITER ECH upper launcher

Author

Strauss, D., primary, Aiello, G., additional, Chavan, R., additional, Cirant, S., additional, deBaar, M., additional, Farina, D., additional, Gantenbein, G., additional, Goodman, T., additional, Henderson, M.A., additional, Kasparek, W., additional, Kleefeldt, K., additional, Landis, J.-D., additional, Meier, A., additional, Moro, A., additional, Plaum, B., additional, Poli, E., additional, Ramponi, G., additional, Ronden, D., additional, Saibene, G., additional, Sanchez, F., additional, Sautter, O., additional, Scherer, T., additional, Schreck, S., additional, Serikov, A., additional, Sozzi, C., additional, Spaeh, P., additional, Vaccaro, A., additional, and Zohm, H., additional

Published
2011
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21. An overview of the ITER electron cyclotron H&CD system

Author

Henderson, M., primary, Albajar, F., additional, Alberti, S., additional, Baruah, U., additional, Bigelow, T., additional, Becket, B., additional, Bertizzolo, R., additional, Bonicelli, T., additional, Bruschi, A., additional, Caughman, J., additional, Chavan, R., additional, Cirant, S., additional, Collazos, A., additional, Darbos, C., additional, de Baar, M., additional, Denisov, G., additional, Farina, D., additional, Gandini, F., additional, Gassman, T., additional, Goodman, T. P., additional, Heidinger, R., additional, Hogge, J. P., additional, Jean, O., additional, Kajiwara, K., additional, Kasparek, W., additional, Kasugai, A., additional, Kern, S., additional, Kobayashi, N., additional, Landis, J. D., additional, Moro, A., additional, Nazare, C., additional, Oda, J., additional, Paganakis, I., additional, Platania, P., additional, Plaum, B., additional, Poli, E., additional, Porte, L., additional, Piosczyk, B., additional, Ramponi, G., additional, Rao, S. L., additional, Rasmussen, D., additional, Ronden, D., additional, Saibene, G., additional, Sakamoto, K., additional, Sanchez, F., additional, Scherer, T., additional, Shapiro, M., additional, Sozzi, C., additional, Spaeh, P., additional, Straus, D., additional, Sauter, O., additional, Takahashi, K., additional, Tanga, A., additional, Temkin, R., additional, Thumm, M., additional, Tran, M. Q., additional, Zohm, H., additional, and Zucca, C., additional

Published
2009
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23. Overview of the ITER EC upper launcher

Author

Henderson, M.A., primary, Heidinger, R., additional, Strauss, D., additional, Bertizzolo, R., additional, Bruschi, A., additional, Chavan, R., additional, Ciattaglia, E., additional, Cirant, S., additional, Collazos, A., additional, Danilov, I., additional, Dolizy, F., additional, Duron, J., additional, Farina, D., additional, Fischer, U., additional, Gantenbein, G., additional, Hailfinger, G., additional, Kasparek, W., additional, Kleefeldt, K., additional, Landis, J.-D., additional, Meier, A., additional, Moro, A., additional, Platania, P., additional, Plaum, B., additional, Poli, E., additional, Ramponi, G., additional, Saibene, G., additional, Sanchez, F., additional, Sauter, O., additional, Serikov, A., additional, Shidara, H., additional, Sozzi, C., additional, Spaeh, P., additional, Udintsev, V.S., additional, Zohm, H., additional, and Zucca, C., additional

Published
2008
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24. Critical Design Issues of the ITER ECH Front Steering Upper Launcher

Author

Henderson, M. A., primary, Chavan, R., additional, Bertizzolo, R., additional, Campbell, D., additional, Duron, J., additional, Dolizy, F., additional, Heidinger, R., additional, Landis, J.-D., additional, Saibene, G., additional, Sanchez, F., additional, Serikov, A., additional, Shidara, H., additional, and Spaeh, P., additional

Published
2008
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26. The Enhanced Performance Launcher Design For The ITER Upper Port ECH Antenna

Author

Henderson, M. A., primary, Chavan, R., additional, Bertizzolo, R., additional, Bruschi, A., additional, Criant, S., additional, Duron, J., additional, Farina, D., additional, Heidinger, R., additional, Landis, J.-D., additional, Poli, E., additional, Ramponi, G., additional, Saibene, G., additional, Sauter, O., additional, Sanchez, F., additional, Shidara, H., additional, Udintsev, V. S., additional, Zohm, H., additional, Zucca, C., additional, Ryan, Philip M., additional, and Rasmussen, David, additional

Published
2007
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28. Microcomputers in US Planning: Past Present and Future

Author

Klosterman, R E and Landis, J D

Abstract

The historical development of microcomputer use in US planning is reviewed and the major ways in which microcomputers are currently being used in planning practice and education are evaluated. Seven applications of microcomputer technology in planning are examined: electronic spreadsheets, data-base management, statistical analysis and forecasting, computer-aided design and drafting, geographic information systems, planning information, and expert systems. Current educational and professional development efforts in this area are evaluated, and the prospects which continued technological advances will have for the use of microcomputers in US planning are assessed.

Published
1988
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29. Gas puff imaging on the TCV tokamak

Author

Offeddu, N., Wuethrich, C., Han, W., Theiler, C., Golfinopoulos, T., Terry, J. L., Marmar, E., Galperti, C., Andrebe, Y., Duval, B. P., Bertizzolo, R., Clement, A., Fevrier, O., Elaian, H., Gonczy, D., and Landis, J. D.

Subjects
fusion, turbulence, nstx, edge plasma, injection system
Abstract

We present the design and operation of a suite of Gas Puff Imaging (GPI) diagnostic systems installed on the Tokamak a Configuration Variable (TCV) for the study of turbulence in the plasma edge and Scrape-Off-Layer (SOL). These systems provide the unique ability to simultaneously collect poloidal 2D images of plasma dynamics at the outboard midplane, around the X-point, in both the High-Field Side (HFS) and Low-Field Side (LFS) SOL, and in the divertor region. We describe and characterize an innovative control system for deuterium and helium gas injection, which is becoming the default standard for the other gas injections at TCV. Extensive pre-design studies and the different detection systems are presented, including an array of avalanche photodiodes and a high-speed CMOS camera. First results with spatial and time resolutions of up to asymptotic to 2 mm and 0.5 mu s, respectively, are described, and future upgrades of the GPI diagnostics for TCV are discussed. (C) 2022 Author(s).

30. Progress on the ITER H&D EC Upper Launcher Steering-Mirror Control System

Author

Collazos, A., Bertizzolo, R., Chavan, R., Dolizy, F., Felici, F., Goodman, T. P., Henderson, M. A., Landis, J.-D., and Sanchez, F.

Subjects
Design, pressure control, Millimeter-wave antennas, Neoclassical Tearing Modes, Cyclotron Current Drive, Stabilization
Abstract

The ITER Heating and Current Drive Upper Launcher (H&CD EC UL) uses a pneumomechanical steering-mirror assembly (SMA) to steer the RF beams for their deposition in the appropriate location in the plasma to control magnetohydrodynamic activity (neoclassical tearing modes (NTMs) and sawtooth oscillations). For NTM stabilization, the mirror rotation needs to be controlled to an accuracy that is better than 0.1 degrees. A 10 degrees . s(-1) mirror steering speed is also required. To assess the performance of the two SMA prototypes that have been manufactured, a test stand that reproduces the expected pneumatic configuration of the UL has been built. So far, only the first SMA prototype has been tested, and tests on the second prototype are foreseen in the 2009-2010 period. The steering angle of the mirror will be deduced from the pressure applied to the mechanism since there is no in situ angle measurement at present. An "off-the-shelf" commercial servo valve with a proportional-integral-derivative controller has been used to control the pressure with good results for the switching cycle. These tests show that a more advanced controller will be required to attain the desired accuracy and speed for the modulation cycles.

31. Progress in the ITER upper launcher MM-wave

Author

Henderson, M.A., Chavan, R., Bertizzolo, R., Collazos, A., Dolizy, F., Landis, J.-D., Sanchez, F., Udintsev, V.S., Saibene, G., Cavinato, M., Bruschi, A., Cirant, S., Farina, D., Moro, A., Platana, P., Ramponi, G., Sozzi, C., Poli, E., Zohm, H., Blaum, B., and Kasparek, W.

32. mm-wave Optical System of the ITER Upper Port EC Launcher

Author

Henderson, M.A., Chavan, R., Bertizzolo, R., Bruschi, A., Cirant, S., Collazos, A., Dolizy, F., Farina, D., Kasparek, W., Landis, J.-D., Moro, A., Platina, P., Plaum, B., Poli, E., Ramponi, G., Saibene, G., Sanchez, F., Shidara, H., and Udintsev, V.S.

33. Design Status of the ITER Upper Port Launcher

Author

Henderson, M.A., Chavan, R., Bertizzolo, R., Bruschi, A., Ciattaglia, E., Cirant, S., Collazos, A., Danilov, I., Dolizy, F., Duron, J., Farina, D., Heidinger, R., Landis, J.-D., Moro, A., Platania, P., Poli, E., Ramponi, G., Saibene, G., Sanchez, F., and O., S

35. Assessing controls on sedimentation rates and sediment organic carbon accretion in beaver ponds.

Author

Rees JC, Lininger KB, Landis JD, and Briles CE

Subjects
Geologic Sediments chemistry, Ponds chemistry, Carbon analysis, Environmental Monitoring methods
Abstract

Beaver dams trap sediment, promote channel-floodplain connectivity, modify biogeochemical cycling and organic carbon (OC) storage, and influence geomorphic form. Beaver-related sediment accumulation has been investigated at longer timescales (e.g., > 1000 years) and shorter timescales (< 10 years), but we lack information on sedimentation and sediment-associated OC accretion rates over multiple decades in relatively persistent beaver ponds (10-100 years old). We coupled field surveys of 45 beaver ponds with historical aerial imagery and radiometric dating with 7 Be, 210 Pb, and 14 C to calculate sedimentation rates, mean sediment depth, and sediment OC content at two study sites in the southern Rocky Mountains, USA. Sedimentation rates in beaver ponds (median = 5.7 cm yr -1 , mean = 11.6 cm yr -1 ) decreased with pond age. Incised, single threaded reaches had greater variability in mean sediment depth compared to less incised reaches. In less incised reaches, mean sediment depth and beaver dam height increased with pond age, indicating more stable dams and depositional environments. Sediment OC content within beaver ponds (median = 0.8 %, mean = 1.7 %) increased with finer sediment grain size distributions. Sediment OC accretion rates in ponds ranged between 0.13 and 23 Mg C ha -1 per year. We used Monte Carlo simulations to estimate it would take ∼100 years or more of uninhibited beaver activity for deposition to laterally reconnect adjacent terraces in the incised study reaches, a common objective within many stream restoration projects. Our findings show that beaver ponds in complex, multi-threaded reaches better retain fine sediment over longer timescales, highlighting the need to incorporate geomorphic context when considering whether beaver can help restore incised river channels and floodplain connectivity, retain fine sediment, and store OC on the landscape., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Published
2024
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