1
|
Doughty CE, Keany JM, Wiebe BC, Rey-Sanchez C, Carter KR, Middleby KB, Cheesman AW, Goulden ML, da Rocha HR, Miller SD, Malhi Y, Fauset S, Gloor E, Slot M, Oliveras Menor I, Crous KY, Goldsmith GR, Fisher JB. Tropical forests are approaching critical temperature thresholds. Nature 2023; 621:105-111. [PMID: 37612501 DOI: 10.1038/s41586-023-06391-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 06/30/2023] [Indexed: 08/25/2023]
Abstract
The critical temperature beyond which photosynthetic machinery in tropical trees begins to fail averages approximately 46.7 °C (Tcrit)1. However, it remains unclear whether leaf temperatures experienced by tropical vegetation approach this threshold or soon will under climate change. Here we found that pantropical canopy temperatures independently triangulated from individual leaf thermocouples, pyrgeometers and remote sensing (ECOSTRESS) have midday peak temperatures of approximately 34 °C during dry periods, with a long high-temperature tail that can exceed 40 °C. Leaf thermocouple data from multiple sites across the tropics suggest that even within pixels of moderate temperatures, upper canopy leaves exceed Tcrit 0.01% of the time. Furthermore, upper canopy leaf warming experiments (+2, 3 and 4 °C in Brazil, Puerto Rico and Australia, respectively) increased leaf temperatures non-linearly, with peak leaf temperatures exceeding Tcrit 1.3% of the time (11% for more than 43.5 °C, and 0.3% for more than 49.9 °C). Using an empirical model incorporating these dynamics (validated with warming experiment data), we found that tropical forests can withstand up to a 3.9 ± 0.5 °C increase in air temperatures before a potential tipping point in metabolic function, but remaining uncertainty in the plasticity and range of Tcrit in tropical trees and the effect of leaf death on tree death could drastically change this prediction. The 4.0 °C estimate is within the 'worst-case scenario' (representative concentration pathway (RCP) 8.5) of climate change predictions2 for tropical forests and therefore it is still within our power to decide (for example, by not taking the RCP 6.0 or 8.5 route) the fate of these critical realms of carbon, water and biodiversity3,4.
Collapse
Affiliation(s)
- Christopher E Doughty
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ, USA.
| | - Jenna M Keany
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ, USA
| | - Benjamin C Wiebe
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ, USA
| | - Camilo Rey-Sanchez
- Department of Marine, Earth and Atmospheric Sciences, North Carolina State University, Raleigh, NC, USA
| | - Kelsey R Carter
- College of Forest Resources and Environmental Sciences, Michigan Technological University, Houghton, MI, USA
- Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Kali B Middleby
- Centre for Tropical Environmental and Sustainability Science, James Cook University, Cairns, Queensland, Australia
| | - Alexander W Cheesman
- Centre for Tropical Environmental and Sustainability Science, James Cook University, Cairns, Queensland, Australia
| | - Michael L Goulden
- Department of Earth System Science, University of California, Irvine, CA, USA
| | - Humberto R da Rocha
- Departamento de Ciencias Atmosfericas, Universidade de São Paulo, São Paulo, Brazil
| | - Scott D Miller
- Atmospheric Sciences Research Center, State University of New York at Albany, Albany, NY, USA
| | - Yadvinder Malhi
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
| | - Sophie Fauset
- School of Geography, Earth and Environmental Sciences, University of Plymouth, Plymouth, UK
| | | | - Martijn Slot
- Smithsonian Tropical Research Institute, Balboa, Ancon, Republic of Panama
| | - Imma Oliveras Menor
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
- AMAP (Botanique et Modélisation de l'Architecture des Plantes et des Végétations), CIRAD, CNRS, INRA, IRD, Université de Montpellier, Montpellier, France
| | - Kristine Y Crous
- Western Sydney University, Hawkesbury Institute for the Environment, Penrith, New South Wales, Australia
| | - Gregory R Goldsmith
- Schmid College of Science and Technology, Chapman University, Orange, CA, USA
| | - Joshua B Fisher
- Schmid College of Science and Technology, Chapman University, Orange, CA, USA
| |
Collapse
|
2
|
Li W, Li J, Wei J, Niu C, Yang D, Jiang B. Response of photosynthesis, the xanthophyll cycle, and wax in Japanese yew ( Taxus cuspidata L.) seedlings and saplings under high light conditions. PeerJ 2023; 11:e14757. [PMID: 36718441 PMCID: PMC9884039 DOI: 10.7717/peerj.14757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 12/27/2022] [Indexed: 01/26/2023] Open
Abstract
In order to understand the adaptative changes of the Japanese yew (Taxus cuspidate L.) to high light conditions, this study investigated gas-exchange, chlorophyll fluorescence, chlorophyll, and the impact of epicuticular wax on the gas-exchange and photoinhibition of Japanese yew seedlings and saplings. The chlorophyll content per unit area and photosynthetic rate in seedling leaves were significantly lower than in sapling leaves. When leaves from seedlings and saplings were exposed to 1,200 μmol·m-2·s-1 photon flux density (PFD) for 2 h, seedling leaves exhibited a greater down-regulation of maximum quantum yield (Fv/Fm) and actual photosystem II efficiency ( Φ PSII). Non-photochemical quenching (NPQ) and high energy quenching (qE) in sapling leaves were much higher than in seedling leaves when both were exposed to 1,200 μmol·m-2·s-1 PFD for 2 h. At a low level of O2, the photorespiration rate (Pr) and the ratio of photorespiration/gross photosynthetic rate (Pr/Pg) in seedling leaves were lower than in sapling leaves when both were exposed to 1,200 μmol·m-2·s-1 PFD, but this difference did not reach statistical significance (P < 0.05). Compared with sapling leaves, seedling leaves exhibited lower levels of xanthophyll pool. Epicuticular wax content on seedling leaves was significantly lower than on sapling leaves. The results of this study showed that wax coverage on the leaf surface decreased the photosynthetic rate in sapling leaves as a consequence of decreased stomatal conductance. Epicuticular wax is related to tree age and photoinhibition prevention in the Japanese yew. It is possible that lower photosynthetic rate, lower NPQ depending on the xanthophyll cycle, and lower deposition of epicuticular wax results in seedling plants that are not adapted to high light conditions.
Collapse
Affiliation(s)
- Wei Li
- Northeast Agricultural University, College of Resources and Environment, Harbin, Heilongjiang, China,Northeast Agricultural University, College of Agriculture, Harbin, Heilongjiang, China
| | - Jiacheng Li
- Northeast Agricultural University, College of Horticulture and Landscape Architecture, Harbin, Heilongjiang, China
| | - Jia Wei
- Northeast Agricultural University, College of Horticulture and Landscape Architecture, Harbin, Heilongjiang, China
| | - Chunda Niu
- Northeast Agricultural University, College of Resources and Environment, Harbin, Heilongjiang, China
| | - Deguang Yang
- Northeast Agricultural University, College of Agriculture, Harbin, Heilongjiang, China
| | - Baiwen Jiang
- Northeast Agricultural University, College of Resources and Environment, Harbin, Heilongjiang, China
| |
Collapse
|
3
|
Khalid MF, Iqbal Khan R, Jawaid MZ, Shafqat W, Hussain S, Ahmed T, Rizwan M, Ercisli S, Pop OL, Alina Marc R. Nanoparticles: The Plant Saviour under Abiotic Stresses. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:nano12213915. [PMID: 36364690 PMCID: PMC9658632 DOI: 10.3390/nano12213915] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 10/26/2022] [Accepted: 11/03/2022] [Indexed: 05/15/2023]
Abstract
Climate change significantly affects plant growth and productivity by causing different biotic and abiotic stresses to plants. Among the different abiotic stresses, at the top of the list are salinity, drought, temperature extremes, heavy metals and nutrient imbalances, which contribute to large yield losses of crops in various parts of the world, thereby leading to food insecurity issues. In the quest to improve plants' abiotic stress tolerance, many promising techniques are being investigated. These include the use of nanoparticles, which have been shown to have a positive effect on plant performance under stress conditions. Nanoparticles can be used to deliver nutrients to plants, overcome plant diseases and pathogens, and sense and monitor trace elements that are present in soil by absorbing their signals. A better understanding of the mechanisms of nanoparticles that assist plants to cope with abiotic stresses will help towards the development of more long-term strategies against these stresses. However, the intensity of the challenge also warrants more immediate approaches to mitigate these stresses and enhance crop production in the short term. Therefore, this review provides an update of the responses (physiological, biochemical and molecular) of plants affected by nanoparticles under abiotic stress, and potentially effective strategies to enhance production. Taking into consideration all aspects, this review is intended to help researchers from different fields, such as plant science and nanoscience, to better understand possible innovative approaches to deal with abiotic stresses in agriculture.
Collapse
Affiliation(s)
- Muhammad Fasih Khalid
- Environmental Science Centre, Qatar University, Doha 2713, Qatar
- Southwest Florida Research and Education Center, Horticultural Sciences Department, Institute of Food and Agricultural Science, University of Florida, Immokalee, FL 34142, USA
| | - Rashid Iqbal Khan
- Institute of Horticultural Sciences, University of Agriculture Faisalabad, Faisalabad 38040, Pakistan
| | | | - Waqar Shafqat
- Department of Forestry, College of Forest Resources, Mississippi State University, Starkville, MI 39759, USA
| | - Sajjad Hussain
- Department of Horticulture, Faculty of Agricultural Science & Technology, Bahauddin Zakariya University, Multan 60800, Pakistan
| | - Talaat Ahmed
- Environmental Science Centre, Qatar University, Doha 2713, Qatar
| | - Muhammad Rizwan
- Office of Academic Research, Office of VP for Research and Graduate Studies, Qatar University, Doha 2713, Qatar
- Correspondence: (M.R.); (O.L.P.); (R.A.M.)
| | - Sezai Ercisli
- Department of Horticulture, Faculty of Agriculture, Ataturk University, 25240 Erzurum, Turkey
| | - Oana Lelia Pop
- Department of Food Science, Faculty of Food Science and Technology, University of Agricultural Science and Veterinary Medicine, 400372 Cluj-Napoca, Romania
- Correspondence: (M.R.); (O.L.P.); (R.A.M.)
| | - Romina Alina Marc
- Department of Food Engineering, Faculty of Food Science and Technology, University of Agricultural Sciences and Veterinary Medicine, 400372 Cluj-Napoca, Romania
- Correspondence: (M.R.); (O.L.P.); (R.A.M.)
| |
Collapse
|