Article
Geochemistry & Geophysics
Wentao An, Mingsen Lin
Summary: This study compares and analyzes eight different model-based incoherent polarimetric decomposition algorithms, using the new concept of generalized polarimetric entropy to describe the polarimetric information change of decomposed components. The polarimetric power entropy and polarimetric residual entropy are used to respectively represent the distribution status of Span values and residual randomness of decomposed components.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2021)
Article
Engineering, Electrical & Electronic
Paul Connetable, Allan Aasbjerg Nielsen, Knut Conradsen, Ernst Krogager, Henning Skriver
Summary: The increased amount of information from fully polarimetric synthetic aperture radar (SAR) provides additional knowledge about ground scatterers. Utilizing the polarimetric information effectively is crucial for target detection. Different approaches have been proposed to summarize the information into polarimetric features, which have been studied in relation to the physical properties of the scatterers. This article aims to review the polarimetric features used for target detection and combine them optimally for vehicle detection in open fields, based on a large airborne dataset in X-, S-, and L-bands.
IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING
(2023)
Article
Engineering, Electrical & Electronic
Arun Babu, Stefan Baumgartner, Gerhard Krieger
Summary: This article evaluates the potential of high-resolution airborne polarimetric synthetic aperture radar (SAR) in remotely estimating road surface roughness on a wide scale. Different SAR models are implemented for surface roughness estimation and a new semi-empirical model is proposed. Techniques such as additive noise subtraction and threshold masking are used to improve the reliability of the estimation. The feasibility of this approach is tested using X-band datasets and the results show good agreement with ground truth values.
IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING
(2022)
Article
Geochemistry & Geophysics
Subhadip Dey, Noelia Romero-Puig, Avik Bhattacharya
Summary: This study proposes a new method for analyzing scattering information to characterize different land cover targets more accurately, and demonstrates its effectiveness using actual data.
IEEE GEOSCIENCE AND REMOTE SENSING LETTERS
(2022)
Article
Environmental Sciences
Rui Guo, Xiaopeng Zhao, Bo Zang, Yi Liang, Jian Bai, Liang Guo
Summary: In this paper, a refined model is proposed to estimate the quad-pol information for the CP mode. The proposed model shows its superiority in estimating the quad-pol information compared to typical reconstruction models. Furthermore, experiments validate the effectiveness of the reconstruction for classification applications using a complex-value convolutional neural network.
Article
Engineering, Electrical & Electronic
Monika Gierszewska, Tomasz Berezowski
Summary: This study investigates the influence of processing parameters on wetland classification. By using various speckle filters and decomposition methods on synthetic aperture radar (SAR) data, and applying a random forest classification model, the study finds that appropriate processing parameters are crucial for SAR data classification.
IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING
(2022)
Article
Geochemistry & Geophysics
Yonghui Han, Pingping Lu, Xiuqing Liu, Wentao Hou, Yao Gao, Weidong Yu, Robert Wang
Summary: This article proposes a modified iterative calibration method using distributed targets that satisfy quasi-azimuth symmetry to calibrate both the channel imbalance and crosstalks of the circular quad-polarimetric synthetic aperture radar systems. The method eliminates the phase ambiguity of the receive channel imbalance ratio commonly found in distributed-target-based algorithms, and its effectiveness is verified through the calibration of Gaofen-3 data and the statistical analysis of residual distortion.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2023)
Article
Engineering, Electrical & Electronic
Mohammed Shokr, Mohammed Dabboor
Summary: Fully polarimetric (FP) and compact polarimetry (CP) modes are advanced technologies of synthetic aperture radar (SAR) that provide additional parameters called polarimetric parameters to fully characterize the received backscattered signal. These parameters have shown potential in improving retrieval of snow and sea ice information. They can be used for sea ice classification, concentration, surface features, identification of new ice versus open water, thickness of thin ice, and discrimination between hummocks and melt pond on multiyear ice surfaces. The review also discusses the operational use of SAR polarimetric data in ice monitoring programs.
IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING
(2023)
Article
Geochemistry & Geophysics
Cornelius Quigley, Camilla Brekke, Torbjorn Eltoft
Summary: In this study, the retrieval results for the dielectric properties of verified oil slick using airborne multifrequency synthetic aperture radar were compared. Two different inversion methods were used and the results showed consistency, especially for low dielectric values.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2022)
Article
Geochemistry & Geophysics
Thibault Taillade, Marcus Engdahl, Diego Fernandez
Summary: In this study, we evaluate the sensitivity of synthetic aperture radar (SAR) to sea surface salinity (SSS), focusing on the variations in dielectric properties and their effects on normalized radar cross section (NRCS) and copolar phase difference (CPD). We also explore the salinity sensitivity to CPD, which has not been previously investigated in the literature.
IEEE GEOSCIENCE AND REMOTE SENSING LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Paul Connetable, Knut Conradsen, Allan Aasbjerg Nielsen, Henning Skriver
Summary: This paper investigates the removal of speckle and the characteristics of the local covariance matrix in polarimetric synthetic aperture radar (SAR) images. Test statistics based on block-diagonality and change detection are used to detect man-made structures with high potential. The results show that the method is effective in highlighting buildings and urban areas, as well as in ship detection at longer wavelengths.
IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING
(2022)
Article
Geochemistry & Geophysics
Chunyu Gou, Honglei Zheng, Jie Zhang
Summary: This study focuses on evaluating the ability of fully polarimetric SAR in estimating the proportion of oil in marine oil spills. A novel method is proposed based on the correlation between different polarimetric features and the oil-water mixing ratio. The results indicate that the mean scattering angle is the most suitable feature for inverting the mixing ratio.
IEEE GEOSCIENCE AND REMOTE SENSING LETTERS
(2023)
Article
Geochemistry & Geophysics
Jorgen Andreas Agersborg, Stian Normann Anfinsen, Jane Uhd Jepsen
Summary: A nonlocal algorithm has been developed for estimating PolSAR covariance matrices on SLC format resolution, inspired by recent work on guided NLM speckle filtering. By considering patchwise dissimilarities in SAR and optical domains, the algorithm sets weights for estimating the target vectors' outer product. This method demonstrates better preservation of local structure compared to previous filtering methods and can be applied in other settings requiring preservation of SLC format resolution.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2022)
Article
Geochemistry & Geophysics
Junjun Yin, Tao Wang, Yanlei Du, Xiyun Liu, Liangjiang Zhou, Jian Yang
Summary: In this study, the SLIC clustering function was modified to adapt to the characteristics of polarimetric SAR images, with a new initialization method and the embedding of four classic statistical distances. Comparison with other algorithms showed significant improvements in segmentation results.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2022)
Article
Geochemistry & Geophysics
David Tucker, Lee C. Potter
Summary: This article proposes a CNN-based despeckling approach for polarimetric SAR (PolSAR) that uses an invertible transformation and residual learning strategy to process the complex-valued covariance matrices. Experimental results show that the proposed approach can significantly reduce speckle and preserve scene features.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2022)
Article
Ecology
Clement Duvert, Caroline A. Canham, Adria Barbeta, Diego Alvarez Cortes, Lisa Chandler, Andrew J. Harford, Amie Leggett, Samantha A. Setterfield, Chris L. Humphrey, Lindsay B. Hutley
Summary: In a study conducted in tropical northern Australia, the contributions of soil water and groundwater to the dry season water uptake of five riparian tree species were examined using soil water matric potential and water stable isotopes. The results showed that most tree species used a combination of relatively shallow soil moisture and groundwater from the capillary fringe. Neglecting isotopic effects may lead to underestimations of groundwater contributions to tree water uptake, highlighting the importance of considering these effects in source water partitioning assessments. Further research is needed to investigate the causes of deuterium depletion in xylem water.
Article
Biodiversity Conservation
Lindsay B. Hutley, Jason Beringer, Simone Fatichi, Stanislaus J. Schymanski, Matthew Northwood
Summary: This study examined interannual variability and externally forced long-term changes in carbon and water exchange at a high rainfall savanna site in northern Australia. It found significant positive trends in gross primary productivity, ecosystem respiration, net ecosystem productivity, and ecosystem water use efficiency, with radiant energy, soil water content, and precipitation being the dominant drivers of these trends. The study highlights the need to understand fluxes and their drivers from sub-diurnal to decadal scales.
GLOBAL CHANGE BIOLOGY
(2022)
Article
Plant Sciences
Andrea C. Westerband, Ian J. Wright, Allyson S. D. Eller, Lucas A. Cernusak, Peter B. Reich, Oscar Perez-Priego, Shubham S. Chhajed, Lindsay B. Hutley, Caroline E. R. Lehmann
Summary: This study reveals the relationships between wood respiration and physical properties as well as nitrogen concentration in bark and sapwood. The findings suggest that tissue density and thickness have more influence on respiration than nitrogen concentration. Australian species show lower respiration rates and nitrogen concentration compared to global species, and the respiration-nitrogen relationships are less steep.
Review
Biodiversity Conservation
Jason Beringer, Caitlin E. Moore, Jamie Cleverly, David Campbell, Helen Cleugh, Martin G. De Kauwe, Miko U. F. Kirschbaum, Anne Griebel, Sam Grover, Alfredo Huete, Lindsay B. Hutley, Johannes Laubach, Tom Van Niel, Stefan K. Arndt, Alison C. Bennett, Lucas A. Cernusak, Derek Eamus, Cacilia M. Ewenz, Jordan P. Goodrich, Mingkai Jiang, Nina Hinko-Najera, Peter Isaac, Sanaa Hobeichi, Juergen Knauer, Georgia R. Koerber, Michael Liddell, Xuanlong Ma, Craig Macfarlane, Ian D. McHugh, Belinda E. Medlyn, Wayne S. Meyer, Alexander J. Norton, Jyoteshna Owens, Andy Pitman, Elise Pendall, Suzanne M. Prober, Ram L. Ray, Natalia Restrepo-Coupe, Sami W. Rifai, David Rowlings, Louis Schipper, Richard P. Silberstein, Lina Teckentrup, Sally E. Thompson, Anna M. Ukkola, Aaron Wall, Ying-Ping Wang, Tim J. Wardlaw, William Woodgate
Summary: The Australian and New Zealand flux research and monitoring network, OzFlux, celebrated its 20th anniversary by reflecting on the lessons learned from two decades of ecosystem studies on global change biology. The network has provided valuable knowledge, information, and data not only for ecosystem researchers, but also for other users. This article focuses on eight key lessons in various areas of research and highlights the importance of long-term flux observations.
GLOBAL CHANGE BIOLOGY
(2022)
Article
Ecology
Catherine E. Lovelock, Maria F. Adame, Jennifer Bradley, Sabine Dittmann, Valerie Hagger, Sharyn M. Hickey, Lindsay B. Hutley, Alice Jones, Jeffrey J. Kelleway, Paul S. Lavery, Peter Macreadie, Damien T. Maher, Soraya McGinley, Alice McGlashan, Sarah Perry, Luke Mosley, Kerrylee Rogers, James Z. Sippo
Summary: The restoration of coastal wetlands has the potential to provide climate change mitigation and adaptation benefits, support biodiversity, and offer additional ecosystem services. Developing rigorous methods for quantifying blue carbon sequestration during restoration is crucial.
RESTORATION ECOLOGY
(2022)
Article
Biodiversity Conservation
Tommaso Jucker, Fabian Jorg Fischer, Jerome Chave, David A. Coomes, John Caspersen, Arshad Ali, Grace Jopaul Loubota Panzou, Ted R. Feldpausch, Daniel Falster, Vladimir A. Usoltsev, Stephen Adu-Bredu, Luciana F. Alves, Mohammad Aminpour, Ilondea B. Angoboy, Niels P. R. Anten, Cecile Antin, Yousef Askari, Rodrigo Munoz, Narayanan Ayyappan, Patricia Balvanera, Lindsay Banin, Nicolas Barbier, John J. Battles, Hans Beeckman, Yannick E. Bocko, Ben Bond-Lamberty, Frans Bongers, Samuel Bowers, Thomas Brade, Michiel van Breugel, Arthur Chantrain, Rajeev Chaudhary, Jingyu Dai, Michele Dalponte, Kangbeni Dimobe, Jean-Christophe Domec, Jean-Louis Doucet, Remko A. Duursma, Moises Enriquez, Karin Y. van Ewijk, William Farfan-Rios, Adeline Fayolle, Eric Forni, David Forrester, Hammad Gilani, John L. Godlee, Sylvie Gourlet-Fleury, Matthias Haeni, Jefferson S. Hall, Jie-Kun He, Andreas Hemp, Jose L. Hernandez-Stefanoni, Steven Higgins, Robert J. Holdaway, Kiramat Hussain, Lindsay B. Hutley, Tomoaki Ichie, Yoshiko Iida, Hai-sheng Jiang, Puspa Raj Joshi, Hasan Kaboli, Maryam Kazempour Larsary, Tanaka Kenzo, Brian D. Kloeppel, Takashi Kohyama, Suwash Kunwar, Shem Kuyah, Jakub Kvasnica, Siliang Lin, Emily R. Lines, Hongyan Liu, Craig Lorimer, Jean-Joel Loumeto, Yadvinder Malhi, Peter L. Marshall, Eskil Mattsson, Radim Matula, Jorge A. Meave, Sylvanus Mensah, Xiangcheng Mi, Stephane Momo, Glenn R. Moncrieff, Francisco Mora, Sarath P. Nissanka, Kevin L. O'Hara, Steven Pearce, Raphael Pelissier, Pablo L. Peri, Pierre Ploton, Lourens Poorter, Mohsen Javanmiri Pour, Hassan Pourbabaei, Juan Manuel Dupuy-Rada, Sabina C. Ribeiro, Casey Ryan, Anvar Sanaei, Jennifer Sanger, Michael Schlund, Giacomo Sellan, Alexander Shenkin, Bonaventure Sonke, Frank J. Sterck, Martin Svatek, Kentaro Takagi, Anna T. Trugman, Farman Ullah, Matthew A. Vadeboncoeur, Ahmad Valipour, Mark C. Vanderwel, Alejandra G. Vovides, Weiwei Wang, Li-Qiu Wang, Christian Wirth, Murray Woods, Wenhua Xiang, Fabiano de Aquino Ximenes, Yaozhan Xu, Toshihiro Yamada, Miguel A. Zavala
Summary: Data capturing multiple axes of tree size and shape are crucial for ecological research. To overcome the challenge of obtaining such data, researchers have developed the Tallo database, which includes georeferenced and taxonomically standardized records of individual trees from around the world.
GLOBAL CHANGE BIOLOGY
(2022)
Article
Plant Sciences
Cassandra Rowe, Emma Rehn, Michael Brand, Lindsay B. B. Hutley, Rainy Comley, Vladimir Levchenko, Costijn Zwart, Christopher M. M. Wurster, Michael I. Bird
Summary: This study explores the plant patterns in the Holocene era in the eucalypt savannas of northern Australia. It reveals that savannas are not homogeneous and are influenced by multiple dimensions of plant changes, such as climate-vegetation relationships and large disturbance events.
JOURNAL OF VEGETATION SCIENCE
(2022)
Article
Multidisciplinary Sciences
Amy E. Zanne, Habacuc Flores-Moreno, Jeff R. Powell, William K. Cornwell, James W. Dalling, Amy T. Austin, Aimee T. Classen, Paul Eggleton, Kei-Ichi Okada, Catherine L. Parr, E. Carol Adair, Stephen Adu-Bredu, Md Azharul Alam, Carolina Alvarez-Garzon, Deborah Apgaua, Roxana Aragon, Marcelo Ardon, Stefan K. Arndt, Louise A. Ashton, Nicholas A. Barber, Jacques Beauchene, Matty P. Berg, Jason Beringer, Matthias M. Boer, Jose Antonio Bonet, Katherine Bunney, Tynan J. Burkhardt, Dulcineia Carvalho, Dennis Castillo-Figueroa, Lucas A. Cernusak, Alexander W. Cheesman, Taina M. Cirne-Silva, Jamie R. Cleverly, Johannes H. C. Cornelissen, Timothy J. Curran, Andre M. D'Angioli, Caroline Dallstream, Nico Eisenhauer, Fidele Evouna Ondo, Alex Fajardo, Romina D. Fernandez, Astrid Ferrer, Marco A. L. Fontes, Mark L. Galatowitsch, Grizelle Gonzalez, Felix Gottschall, Peter R. Grace, Elena Granda, Hannah M. Griffiths, Mariana Guerra Lara, Motohiro Hasegawa, Mariet M. Hefting, Nina Hinko-Najera, Lindsay B. Hutley, Jennifer Jones, Anja Kahl, Mirko Karan, Joost A. Keuskamp, Tim Lardner, Michael Liddell, Craig Macfarlane, Cate Macinnis-Ng, Ravi F. Mariano, M. Soledad Mendez, Wayne S. Meyer, Akira S. Mori, Aloysio S. Moura, Matthew Northwood, Roma Ogaya, Rafael S. Oliveira, Alberto Orgiazzi, Juliana Pardo, Guille Peguero, Josep Penuelas, Luis I. Perez, Juan M. Posada, Cecilia M. Prada, Tomas Privetivy, Suzanne M. Prober, Jonathan Prunier, Gabriel W. Quansah, Victor Resco De Dios, Ronny Richter, Mark P. Robertson, Lucas F. Rocha, Megan A. Rua, Carolina Sarmiento, Richard P. Silberstein, Mateus C. Silva, Flavia Freire Siqueira, Matthew Glenn Stillwagon, Jacqui Stol, Melanie K. Taylor, Francois P. Teste, David Y. P. Tng, David Tucker, Manfred Turke, Michael D. Ulyshen, Oscar J. Valverde-Barrantes, Eduardo Van den Berg, Richard S. P. Van Logtestijn, G. F. (Ciska) Veen, Jason G. Vogel, Timothy J. Wardlaw, Georg Wiehl, Christian Wirth, Michaela J. Woods, Paul-Camilo Zalamea
Summary: Deadwood is a significant global carbon store, with its size influenced by biotic decay. Termites, as important decomposers in the tropics, show higher sensitivity to temperature changes than microbes in terms of wood consumption. As the climate warms and shifts towards tropical climates, termites are likely to have a greater impact on wood decay.
Article
Water Resources
Clement Duvert, Han-She Lim, Dylan J. Irvine, Michael I. Bird, Adrian M. Bass, Sarah O. Tweed, Lindsay B. Hutley, Niels C. Munksgaard
Summary: This review summarizes the research on hydrological processes in tropical streams and rivers in Australia. It highlights the initial efforts in understanding the hydrological response of forested ecosystems in the humid tropics and more recent work in savannas of the seasonal tropics. The review presents recent findings from modelling and tracer studies, identifies knowledge gaps, and discusses the potential effects of climate change and water resource development on the hydrology of the region.
JOURNAL OF HYDROLOGY-REGIONAL STUDIES
(2022)
Article
Limnology
Vanessa Solano, Clement Duvert, Christian Birkel, Damien T. T. Maher, Erica A. A. Garcia, Lindsay B. B. Hutley
Summary: This study used high-frequency measurements of dissolved O2 and CO2 concentrations to estimate the potential contribution of stream metabolism to the CO2 evasion flux in a tropical lowland headwater stream. The results showed that the stream was heterotrophic all year round, with positive net ecosystem productivity (NEP) values. Despite seasonal changes, the CO2 excess was likely transported downstream and emitted to the atmosphere.
LIMNOLOGY AND OCEANOGRAPHY
(2023)
Article
Environmental Sciences
Christine T. Y. Chung, Pandora Hope, Lindsay B. Hutley, Josephine Brown, Norman C. Duke
Summary: The mangroves in the Gulf of Carpentaria, Australia, face risks to their health due to projected changes in sea level variability and increasing maximum daily temperatures.
COMMUNICATIONS EARTH & ENVIRONMENT
(2023)
Article
Ecology
Catherine E. Lovelock, Maria Fernanda Adame, Sabine Dittmann, Valerie Hagger, Sharyn M. Hickey, Lindsay I. Hutley, Alice Jones, Jeffrey J. Kelleway, Paul S. Lavery, Peter I. Macreadie, Damien T. Maher, Luke Mosley, Kerrylee Rogers, James Z. Sippo
Summary: The Blue Carbon Accounting Model (BlueCAM) is a tool for tidal restoration projects in the Australian carbon market. However, it does not subtract allochthonous carbon from estimated net abatement. Despite this, BlueCAM is transparent, conservative, feasible, and consistent with international guidelines and Australian standards.
RESTORATION ECOLOGY
(2023)
Article
Environmental Sciences
Neil Saintilan, Yujie Sun, Catherine E. Lovelock, Kerrylee Rogers, Madeline Goddard, Lindsay B. Hutley, Jeffrey Kelleway, Luke Mosley, Sabine Dittmann, Nicole Cormier, Kirti K. Lal, Alice Jones
Summary: Australian tidal wetlands, which differ from northern hemisphere systems, have been studied through a network of monitoring stations to assess their response to sea-level rise. Mangroves have shown higher rates of accretion and elevation gain compared to other types of tidal wetlands. However, the rate of subsidence in the shallow substrate increased with higher accretion rates, resulting in lower overall elevation gain. The Australian SET-MH network serves as an important benchmark for future wetland responses to sea-level rise.
ESTUARIES AND COASTS
(2023)
Article
Geosciences, Multidisciplinary
Remko C. Nijzink, Jason Beringer, Lindsay B. Hutley, Stanislaus J. Schymanski
Summary: The Vegetation Optimality Model (VOM) is an optimality-based water-vegetation model that predicts vegetation properties and behavior. This study updated the model and assessed the impacts of these updates on the original results. The changes had modest effects on the simulation of evapotranspiration and gross primary productivity, with the greatest impacts from free drainage conditions and modified soil texture. The optimization approach of the model proved to be robust.
GEOSCIENTIFIC MODEL DEVELOPMENT
(2022)
Article
Geosciences, Multidisciplinary
Remko C. Nijzink, Jason Beringer, Lindsay B. Hutley, Stanislaus J. Schymanski
Summary: Most terrestrial biosphere models rely on local vegetation information, while optimality-based models predict vegetation properties based on general principles. This study examined the ability of an optimality-based model to predict vegetation behavior and found that it performed similarly to or better than traditional models in reproducing seasonal and annual fluxes, but still had some deviations from observations.
HYDROLOGY AND EARTH SYSTEM SCIENCES
(2022)