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Mata-Guel EO, Soh MCK, Butler CW, Morris RJ, Razgour O, Peh KSH. Impacts of anthropogenic climate change on tropical montane forests: an appraisal of the evidence. Biol Rev Camb Philos Soc 2023; 98:1200-1224. [PMID: 36990691 DOI: 10.1111/brv.12950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 03/08/2023] [Accepted: 03/10/2023] [Indexed: 03/31/2023]
Abstract
In spite of their small global area and restricted distributions, tropical montane forests (TMFs) are biodiversity hotspots and important ecosystem services providers, but are also highly vulnerable to climate change. To protect and preserve these ecosystems better, it is crucial to inform the design and implementation of conservation policies with the best available scientific evidence, and to identify knowledge gaps and future research needs. We conducted a systematic review and an appraisal of evidence quality to assess the impacts of climate change on TMFs. We identified several skews and shortcomings. Experimental study designs with controls and long-term (≥10 years) data sets provide the most reliable evidence, but were rare and gave an incomplete understanding of climate change impacts on TMFs. Most studies were based on predictive modelling approaches, short-term (<10 years) and cross-sectional study designs. Although these methods provide moderate to circumstantial evidence, they can advance our understanding on climate change effects. Current evidence suggests that increasing temperatures and rising cloud levels have caused distributional shifts (mainly upslope) of montane biota, leading to alterations in biodiversity and ecological functions. Neotropical TMFs were the best studied, thus the knowledge derived there can serve as a proxy for climate change responses in under-studied regions elsewhere. Most studies focused on vascular plants, birds, amphibians and insects, with other taxonomic groups poorly represented. Most ecological studies were conducted at species or community levels, with a marked paucity of genetic studies, limiting understanding of the adaptive capacity of TMF biota. We thus highlight the long-term need to widen the methodological, thematic and geographical scope of studies on TMFs under climate change to address these uncertainties. In the short term, however, in-depth research in well-studied regions and advances in computer modelling approaches offer the most reliable sources of information for expeditious conservation action for these threatened forests.
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Affiliation(s)
- Erik O Mata-Guel
- School of Biological Sciences, University of Southampton, Highfield Campus, Southampton, SO17 1BJ, UK
| | - Malcolm C K Soh
- National Park Boards, 1 Cluny Road, Singapore, 259569, Singapore
| | - Connor W Butler
- School of Biological Sciences, University of Southampton, Highfield Campus, Southampton, SO17 1BJ, UK
| | - Rebecca J Morris
- School of Biological Sciences, University of Southampton, Highfield Campus, Southampton, SO17 1BJ, UK
| | - Orly Razgour
- Biosciences, University of Exeter, Exeter, EX4 4PS, UK
| | - Kelvin S-H Peh
- School of Biological Sciences, University of Southampton, Highfield Campus, Southampton, SO17 1BJ, UK
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Chen Z, Yu G. Spatial variations and controls of carbon use efficiency in China's terrestrial ecosystems. Sci Rep 2019; 9:19516. [PMID: 31862964 PMCID: PMC6925132 DOI: 10.1038/s41598-019-56115-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 12/07/2019] [Indexed: 11/08/2022] Open
Abstract
Carbon use efficiency (CUE), one of the most important eco-physiological parameters, represents the capacity of plants to transform carbon into new biomass. Understanding the variations and controls of CUE is crucial for regional carbon assessment. Here, we used 15-years of continuous remote sensing data to examine the variations of CUE across broad geographic and climatic gradients in China. The results showed that the vegetation CUE was averaged to 0.54 ± 0.11 with minor interannual variation. However, the CUE greatly varied with geographic gradients and ecosystem types. Forests have a lower CUE than grasslands and croplands. Evergreen needleleaf forests have a higher CUE than other forest types. Climate factors (mean annual temperature (MAT), precipitation (MAP) and the index of water availability (IWA)) dominantly regulated the spatial variations of CUE. The CUE exhibited a linear decrease with enhanced MAT and MAP and a parabolic response to the IWA. Furthermore, the responses of CUE to environmental change varied with individual ecosystem type. In contrast, precipitation exerted strong control on CUE in grassland, while in forest and cropland, the CUE was mainly controlled by the available water. This study identifies the variations and response of CUE to environmental drivers in China, which will be valuable for the regional assessment of carbon cycling dynamics under future climate change.
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Affiliation(s)
- Zhi Chen
- Synthesis Research Center of Chinese Ecosystem Research Network, and Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China.
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Guirui Yu
- Synthesis Research Center of Chinese Ecosystem Research Network, and Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China.
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China.
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Malhi Y, Girardin CAJ, Goldsmith GR, Doughty CE, Salinas N, Metcalfe DB, Huaraca Huasco W, Silva-Espejo JE, Del Aguilla-Pasquell J, Farfán Amézquita F, Aragão LEOC, Guerrieri R, Ishida FY, Bahar NHA, Farfan-Rios W, Phillips OL, Meir P, Silman M. The variation of productivity and its allocation along a tropical elevation gradient: a whole carbon budget perspective. THE NEW PHYTOLOGIST 2017; 214:1019-1032. [PMID: 27768811 DOI: 10.1111/nph.14189] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 07/12/2016] [Indexed: 05/12/2023]
Abstract
Why do forest productivity and biomass decline with elevation? To address this question, research to date generally has focused on correlative approaches describing changes in woody growth and biomass with elevation. We present a novel, mechanistic approach to this question by quantifying the autotrophic carbon budget in 16 forest plots along a 3300 m elevation transect in Peru. Low growth rates at high elevations appear primarily driven by low gross primary productivity (GPP), with little shift in either carbon use efficiency (CUE) or allocation of net primary productivity (NPP) between wood, fine roots and canopy. The lack of trend in CUE implies that the proportion of photosynthate allocated to autotrophic respiration is not sensitive to temperature. Rather than a gradual linear decline in productivity, there is some limited but nonconclusive evidence of a sharp transition in NPP between submontane and montane forests, which may be caused by cloud immersion effects within the cloud forest zone. Leaf-level photosynthetic parameters do not decline with elevation, implying that nutrient limitation does not restrict photosynthesis at high elevations. Our data demonstrate the potential of whole carbon budget perspectives to provide a deeper understanding of controls on ecosystem functioning and carbon cycling.
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Affiliation(s)
- Yadvinder Malhi
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, OX1 3QY, UK
| | - Cécile A J Girardin
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, OX1 3QY, UK
| | - Gregory R Goldsmith
- Ecosystem Fluxes Group, Laboratory for Atmospheric Chemistry, Paul Scherrer Institute, Villigen PSI, 5232, Switzerland
| | - Christopher E Doughty
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, OX1 3QY, UK
| | - Norma Salinas
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, OX1 3QY, UK
- Universidad Nacional San Antonio Abad del Cusco, Cusco, Peru
| | - Daniel B Metcalfe
- Department of Physical Geography and Ecosystem Science, Lund University, SE 223 62, Lund, Sweden
| | | | | | | | | | - Luiz E O C Aragão
- Remote Sensing Division, National Institute for Space Research, Av. dos Astronautas, 1.758, São José dos Campos, SP, 12227-010, Brazil
- College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4QD, UK
| | - Rossella Guerrieri
- Centre for Ecological Research and Forestry Applications, CREAF c/o Universidad Autonoma de Barcelona, Edificio C, 08290, Cerdanyola, Barcelona, Spain
- School of Geosciences, University of Edinburgh, Edinburgh, EH8 9XP, UK
| | - Françoise Yoko Ishida
- College of Marine and Environmental Sciences, Centre of Tropical Environmental and Sustainabilility Science, James Cook University, Cairns, Qld, 4870, Australia
| | - Nur H A Bahar
- ARC Centre of Excellence in Plant Energy Biology, Research School of Biology, Building 134, The Australian National University, Canberra, ACT, 2601, Australia
| | - William Farfan-Rios
- Department of Biology, Wake Forest University, Winston-Salem, NC, 27109, USA
| | | | - Patrick Meir
- School of Geosciences, University of Edinburgh, Edinburgh, EH8 9XP, UK
- ARC Centre of Excellence in Plant Energy Biology, Research School of Biology, Building 134, The Australian National University, Canberra, ACT, 2601, Australia
| | - Miles Silman
- Department of Biology, Wake Forest University, Winston-Salem, NC, 27109, USA
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Marthews TR, Malhi Y, Girardin CAJ, Silva Espejo JE, Aragão LEOC, Metcalfe DB, Rapp JM, Mercado LM, Fisher RA, Galbraith DR, Fisher JB, Salinas-Revilla N, Friend AD, Restrepo-Coupe N, Williams RJ. Simulating forest productivity along a neotropical elevational transect: temperature variation and carbon use efficiency. GLOBAL CHANGE BIOLOGY 2012; 18:2882-2898. [PMID: 24501065 DOI: 10.1111/j.1365-2486.2012.02728.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Accepted: 02/14/2012] [Indexed: 06/03/2023]
Abstract
A better understanding of the mechanisms controlling the magnitude and sign of carbon components in tropical forest ecosystems is important for reliable estimation of this important regional component of the global carbon cycle. We used the JULES vegetation model to simulate all components of the carbon balance at six sites along an Andes-Amazon transect across Peru and Brazil and compared the results to published field measurements. In the upper montane zone the model predicted a lack of forest vegetation, indicating a need for better parameterization of the responses of cloud forest vegetation within the model. In the lower montane and lowland zones simulated ecosystem productivity and respiration were predicted with reasonable accuracy, although not always within the error bounds of the observations. Model-predicted carbon use efficiency in this transect surprisingly did not increase with elevation, but remained close to the 'temperate' value 0.5. Upper montane forests were predicted to allocate ~50% of carbon fixation to biomass maintenance and growth, despite available measurements showing that they only allocate ~33%. This may be explained by elevational changes in the balance between growth and maintenance respiration within the forest canopy, as controlled by both temperature- and pressure-mediated processes, which is not yet well represented in current vegetation models.
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Affiliation(s)
- Toby R Marthews
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, OX1 3QY, UK
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