Institution
Commonwealth Scientific and Industrial Research Organisation
Government•Canberra, Australian Capital Territory, Australia•
About: Commonwealth Scientific and Industrial Research Organisation is a government organization based out in Canberra, Australian Capital Territory, Australia. It is known for research contribution in the topics: Population & Soil water. The organization has 33765 authors who have published 79910 publications receiving 3356114 citations.
Topics: Population, Soil water, Climate change, Gene, Context (language use)
Papers published on a yearly basis
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TL;DR: It is proposed that wheat varieties with a deeper root system, a redistribution of branch root density from the surface to depth, and with greater radial hydraulic conductivity at depth would have higher yields in rainfed systems where crops rely on deep water for grain fill.
Abstract: Wheat yields globally will depend increasingly on good management to conserve rainfall and new varieties that use water efficiently for grain production. Here we propose an approach for developing new varieties to make better use of deep stored water. We focus on water-limited wheat production in the summer-dominant rainfall regions of India and Australia, but the approach is generally applicable to other environments and root-based constraints. Use of stored deep water is valuable because it is more predictable than variable in-season rainfall and can be measured prior to sowing. Further, this moisture is converted into grain with twice the efficiently of in-season rainfall since it is taken up later in crop growth during the grain-filling period when the roots reach deeper layers. We propose that wheat varieties with a deeper root system, a redistribution of branch root density from the surface to depth, and with greater radial hydraulic conductivity at depth would have higher yields in rainfed systems where crops rely on deep water for grain fill. Developing selection systems for mature root system traits is challenging as there are limited high-throughput phenotyping methods for roots in the field, and there is a risk that traits selected in the lab on young plants will not translate into mature root system traits in the field. We give an example of a breeding programme that combines laboratory and field phenotyping with proof of concept evaluation of the trait at the beginning of the selection programme. This would greatly enhance confidence in a high-throughput laboratory or field screen, and avoid investment in screens without yield value. This approach requires careful selection of field sites and years that allow expression of deep roots and increased yield. It also requires careful selection and crossing of germplasm to allow comparison of root expression among genotypes that are similar for other traits, especially flowering time and disease and toxicity resistances. Such a programme with field and laboratory evaluation at the outset will speed up delivery of varieties with improved root systems for higher yield.
625 citations
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Max Planck Society1, University of Innsbruck2, Potsdam Institute for Climate Impact Research3, Oeschger Centre for Climate Change Research4, University of Aberdeen5, International Institute of Minnesota6, University of Antwerp7, University of Arizona8, Stockholm University9, ETH Zurich10, Commonwealth Scientific and Industrial Research Organisation11, Centre national de la recherche scientifique12, Aix-Marseille University13, Technical University of Denmark14, University of Potsdam15, University of Alcalá16
TL;DR: It is found that ecosystem responses can exceed the duration of the climate impacts via lagged effects on the carbon cycle, and forests are expected to exhibit the largest net effect of extremes due to their large carbon pools and fluxes, potentially large indirect and lagged impacts, and long recovery time to regain previous stocks.
Abstract: Extreme droughts, heat waves, frosts, precipitation, wind storms and other climate extremes may impact the structure, composition and functioning of terrestrial ecosystems, and thus carbon cycling and its feedbacks to the climate system. Yet, the interconnected avenues through which climate extremes drive ecological and physiological processes and alter the carbon balance are poorly understood. Here, we review the literature on carbon cycle relevant responses of ecosystems to extreme climatic events. Given that impacts of climate extremes are considered disturbances, we assume the respective general disturbance-induced mechanisms and processes to also operate in an extreme context. The paucity of well-defined studies currently renders a quantitative meta-analysis impossible, but permits us to develop a deductive framework for identifying the main mechanisms (and coupling thereof) through which climate extremes may act on the carbon cycle. We find that ecosystem responses can exceed the duration of the climate impacts via lagged effects on the carbon cycle. The expected regional impacts of future climate extremes will depend on changes in the probability and severity of their occurrence, on the compound effects and timing of different climate extremes, and on the vulnerability of each land-cover type modulated by management. Although processes and sensitivities differ among biomes, based on expert opinion, we expect forests to exhibit the largest net effect of extremes due to their large carbon pools and fluxes, potentially large indirect and lagged impacts, and long recovery time to regain previous stocks. At the global scale, we presume that droughts have the strongest and most widespread effects on terrestrial carbon cycling. Comparing impacts of climate extremes identified via remote sensing vs. ground-based observational case studies reveals that many regions in the (sub-)tropics are understudied. Hence, regional investigations are needed to allow a global upscaling of the impacts of climate extremes on global carbon-climate feedbacks.
625 citations
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TL;DR: In this article, a multilayer model is presented which solves simultaneously for leaf stomatal conductance, CO2 assimilation and the energy balance as a function of leaf position within canopies of well-watered vegetation.
Abstract: A model is presented which solves simultaneously for leafâscale stomatal conductance, CO2 assimilation and the energy balance as a function of leaf position within canopies of wellâwatered vegetation. Fluxes and conductances were calculated separately for sunlit and shaded leaves. A linear dependence of photosynthetic capacity on leaf nitrogen content was assumed, while leaf nitrogen content and light intensity were assumed to decrease exponentially within canopies. Separate extinction coefficients were used for diffuse and direct beam radiation. An efficient Gaussian integration technique was used to compute fluxes and mean conductances for the canopy. The multilayer model synthesizes current knowledge of radiation penetration, leaf physiology and the physics of evaporation and provides insights into the response of whole canopies to multiple, interacting factors. The model was also used to explore sources of variation in the slopes of two simple parametric models (nitrogenâ and lightâuse efficiency), and to set bounds on the magnitudes of the parameters. For canopies low in total N, daily assimilation rates are â¼10% lower when leaf N is distributed uniformly than when the same total N is distributed according to the exponentially decreasing profile of absorbed radiation. However, gains are negligible for plants with high N concentrations. Canopy conductance, Gc should be calculated as Gc=AI(fslgsl+fshgsh), where I is leaf area index, fsi and fsh are the fractions of sunlit and shaded leaves at each level, and gsi and gsh are the corresponding stomatal conductances. Simple addition of conductances without this weighting causes errors in transpiration calculated using the âbigâleafâ version of the PenmanâMonteith equation. Partitioning of available energy between sensible and latent heat is very responsive to the parameter describing the sensitivity of stomata to the atmospheric humidity deficit. This parameter also affects canopy conductance, but has a relatively small impact on canopy assimilation. Simple parametric models are useful for extrapolating understanding from small to large scales, but the complexity of real ecosystems is thus subsumed in unexplained variations in parameter values. Simulations with the multilayer model show that both nitrogenâ and radiationâuse efficiencies depend on plant nutritional status and the diffuse component of incident radiation, causing a 2â to 3âfold variation in these efficiencies.
624 citations
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Helmholtz-Zentrum Berlin1, Ben-Gurion University of the Negev2, National Renewable Energy Laboratory3, University of Erlangen-Nuremberg4, Forschungszentrum Jülich5, University of Rome Tor Vergata6, Massachusetts Institute of Technology7, Princeton University8, Chulalongkorn University9, Wuhan University of Technology10, Karlsruhe Institute of Technology11, University of Grenoble12, Commonwealth Scientific and Industrial Research Organisation13, University of Michigan14, Sapienza University of Rome15, École Polytechnique Fédérale de Lausanne16, VU University Amsterdam17, University of Jena18, Bangor University19, University of Maryland, College Park20, University of California, Davis21, Dalian Institute of Chemical Physics22, Shaanxi Normal University23, Chinese Academy of Sciences24, University of Southern Denmark25, University of Colorado Boulder26, State University of Campinas27, Boğaziçi University28, Sungkyunkwan University29, Swansea University30, Technische Universität Darmstadt31, University of Oxford32, University of Cambridge33, Skolkovo Institute of Science and Technology34, Yonsei University35, Imperial College London36
TL;DR: A consensus between researchers in the field is reported on procedures for testing perovskite solar cell stability, which are based on the International Summit on Organic Photovoltaic Stability (ISOS) protocols, and additional procedures to account for properties specific to PSCs are proposed.
Abstract: Improving the long-term stability of perovskite solar cells is critical to the deployment of this technology. Despite the great emphasis laid on stability-related investigations, publications lack consistency in experimental procedures and parameters reported. It is therefore challenging to reproduce and compare results and thereby develop a deep understanding of degradation mechanisms. Here, we report a consensus between researchers in the field on procedures for testing perovskite solar cell stability, which are based on the International Summit on Organic Photovoltaic Stability (ISOS) protocols. We propose additional procedures to account for properties specific to PSCs such as ion redistribution under electric fields, reversible degradation and to distinguish ambient-induced degradation from other stress factors. These protocols are not intended as a replacement of the existing qualification standards, but rather they aim to unify the stability assessment and to understand failure modes. Finally, we identify key procedural information which we suggest reporting in publications to improve reproducibility and enable large data set analysis. Reliability of stability data for perovskite solar cells is undermined by a lack of consistency in the test conditions and reporting. This Consensus Statement outlines practices for testing and reporting stability tailoring ISOS protocols for perovskite devices.
621 citations
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TL;DR: The synthesized COFs were successfully delaminated using a simple, safe, and environmentally friendly mechanical grinding route to transform into covalent organic nanosheets (CONs) and were well characterized via transmission electron microscopy and atomic force microscopy.
Abstract: A series of five thermally and chemically stable functionalized covalent organic frameworks (COFs), namely, TpPa-NO2, TpPa-F4, TpBD-(NO2)2, TpBD-Me2, and TpBD-(OMe)2 were synthesized by employing the solvothermal aldehyde-amine Schiff base condensation reaction. In order to complete the series, previously reported TpPa-1, TpPa-2, and TpBD have also been synthesized, and altogether, eight COFs were fully characterized through powder X-ray diffraction (PXRD), Fourier transform IR (FT-IR) spectroscopy, 13C solid-state NMR spectroscopy, and thermogravimetric analysis. These COFs are crystalline, permanently porous, and stable in boiling water, acid (9 N HCl), and base (3 N NaOH). The synthesized COFs (all eight) were successfully delaminated using a simple, safe, and environmentally friendly mechanical grinding route to transform into covalent organic nanosheets (CONs) and were well characterized via transmission electron microscopy and atomic force microscopy. Further PXRD and FT-IR analyses confirm that the...
620 citations
Authors
Showing all 33864 results
Name | H-index | Papers | Citations |
---|---|---|---|
David R. Williams | 178 | 2034 | 138789 |
Mark E. Cooper | 158 | 1463 | 124887 |
Kevin J. Gaston | 150 | 750 | 85635 |
Liming Dai | 141 | 781 | 82937 |
John D. Potter | 137 | 795 | 75310 |
Lei Zhang | 135 | 2240 | 99365 |
Harold A. Mooney | 135 | 450 | 100404 |
Frederick M. Ausubel | 133 | 389 | 60365 |
Rajkumar Buyya | 133 | 1066 | 95164 |
Robert B. Jackson | 132 | 458 | 91332 |
Peter Hall | 132 | 1640 | 85019 |
Frank Caruso | 131 | 641 | 61748 |
Paul J. Crutzen | 130 | 461 | 80651 |
Andrew Y. Ng | 130 | 345 | 164995 |
Lei Zhang | 130 | 2312 | 86950 |