Showing papers by "Guy F. Midgley published in 2021"
TL;DR: In this article, the authors analyzed >8000 risk projections of the projected impact of climate change on 273 areas of exceptional biodiversity, including terrestrial and marine environments and found that climate change is projected to negatively impact all assessed areas, but endemic species are consistently more adversely impacted.
87 citations
DOI•
Alfred Wegener Institute for Polar and Marine Research1, University of the West Indies2, University of Pretoria3, Karlsruhe Institute of Technology4, Australian National University5, British Antarctic Survey6, Scottish Association for Marine Science7, National Parks Board8, University of British Columbia9, Case Western Reserve University10, Conservation International11, King Abdullah University of Science and Technology12, Leipzig University13, Stellenbosch University14, University of São Paulo15, Technical University of Kenya16, University of Queensland17, Chiba University18, Russian Academy19, University of Erlangen-Nuremberg20, Wageningen University and Research Centre21, University of California, San Diego22, Macquarie University23, Kyushu University24, Pontifical Catholic University of Chile25, Rutgers University26, Institut de recherche pour le développement27, Ikerbasque28, Rio de Janeiro State University29, Potsdam Institute for Climate Impact Research30, Autonomous University of Barcelona31, National Centre for Biological Sciences32, Haramaya University33, University of Aberdeen34, Fisheries and Oceans Canada35, Pontifical Catholic University of Rio de Janeiro36, Indian Institute of Science37, University of Cape Town38, Amazon.com39, University of Texas at Austin40, National University of Cordoba41, University of Bern42, University of Tokyo43, Chinese Academy of Sciences44, Food and Agriculture Organization45
65 citations
TL;DR: It is concluded that substantial future biome changes due to climate and CO2 changes are likely across Africa, and adaptation strategies must be highly flexible.
Abstract: Anthropogenic climate change is expected to impact ecosystem structure, biodiversity and ecosystem services in Africa profoundly. We used the adaptive Dynamic Global Vegetation Model (aDGVM), which was originally developed and tested for Africa, to quantify sources of uncertainties in simulated African potential natural vegetation towards the end of the 21st century. We forced the aDGVM with regionally downscaled high-resolution climate scenarios based on an ensemble of six general circulation models (GCMs) under two representative concentration pathways (RCPs 4.5 and 8.5). Our study assessed the direct effects of climate change and elevated CO2 on vegetation change and its plant-physiological drivers. Total increase in carbon in aboveground biomass in Africa until the end of the century was between 18% to 43% (RCP4.5) and 37% to 61% (RCP8.5) and was associated with woody encroachment into grasslands and increased woody cover in savannas. When direct effects of CO2 on plants were omitted, woody encroachment was muted and carbon in aboveground vegetation changed between -8 to 11% (RCP 4.5) and -22 to -6% (RCP8.5). Simulated biome changes lacked consistent large-scale geographical patterns of change across scenarios. In Ethiopia and the Sahara/Sahel transition zone, the biome changes forecast by the aDGVM were consistent across GCMs and RCPs. Direct effects from elevated CO2 were associated with substantial increases in water use efficiency, primarily driven by photosynthesis enhancement, which may relieve soil moisture limitations to plant productivity. At the ecosystem level, interactions between fire and woody plant demography further promoted woody encroachment. We conclude that substantial future biome changes due to climate and CO2 changes are likely across Africa. Because of the large uncertainties in future projections, adaptation strategies must be highly flexible. Focused research on CO2 effects, and improved model representations of these effects will be necessary to reduce these uncertainties.
29 citations
Stellenbosch University1, University of Vienna2, Monash University, Clayton campus3, University of Cape Town4, King's College London5, Martin Luther University of Halle-Wittenberg6, Université Paris-Saclay7, Free University of Berlin8, Leibniz Association9, African Institute for Mathematical Sciences10
TL;DR: A common framework articulated around six processes is proposed, paving the way for a similar transition in invasion ecology, to better capture the dynamics of multiple alien species introduced in complex communities.
Abstract: CITATION: Latombe, G., et al. 2021. Mechanistic reconciliation of community and invasion ecology. Ecosphere, 12(2):e03359, doi:10.1002/ecs2.3359.
13 citations
TL;DR: The results demonstrate the importance of considering measurements of multivariate phenotypes on individual plants when evaluating trait relationships and how trait variation influences predictions of ecological and evolutionary outcomes.
6 citations
TL;DR: In this article, the authors examine complex system change at the local scale of the southern Cape and Agulhas Bank in South Africa through placing different knowledge bases on climate variability alongside each other.
Abstract: By overlaying terrestrial and marine perspectives, we examine complex system change at the local scale of the southern Cape and Agulhas Bank in South Africa through placing different knowledge bases on climate variability alongside each other. This research adds insights into how social components of complex systems interact with environmental change and contributes to confirming environmental regime shifts in the research area; identifying knowledge disconnects for ecosystem services linked to terrestrial water availability; and highlights scale disconnects in fisher observations in nearand off-shore change. The benefits of examining these diverse bodies of knowledge in parallel across terrestrial and marine systems are evident in the synergies and disconnects that emerge from our integrative approach. Although impossible to eliminate uncertainty around projected climate variability and change, this multi-evidence base strengthens advice for evidence-based, strategic decision making that is locally relevant. The methodology pursued adds to the global learning on overlaying multiple bodies of knowledge in support of sustainability.
5 citations
4 citations
TL;DR: In this paper, the authors investigated the relationship between rainfall constancy and crassulacean acid metabolism (CAM) dependence in the genus Drosanthemum and found that higher CAM dependence might provide an adaptive advantage in increasingly unpredictable rainfall environments when the anatomic exaptation (succulence) was already present.
Abstract: A flexible use of the crassulacean acid metabolism (CAM) has been hypothesised to represent an intermediate stage along a C3 to full CAM evolutionary continuum, when relative contributions of C3 vs CAM metabolism are co-determined by evolutionary history and prevailing environmental constraints. However, evidence for such eco-evolutionary interdependencies is lacking. We studied these interdependencies for the leaf-succulent genus Drosanthemum (Aizoaceae, Southern African Succulent Karoo) by testing for relationships between leaf δ13 C diagnostic for CAM dependence (i.e. contribution of C3 and CAM to net carbon gain), and climatic variables related to temperature and precipitation and their temporal variation. We further quantified the effects of shared phylogenetic ancestry on CAM dependence and its relation to climate. CAM dependence is predicted by rainfall and its temporal variation, with high predictive power of rainfall constancy (temporal entropy). The predictive power of rainfall seasonality and temperature-related variables was negligible. Evolutionary history of the tested clades significantly affected the relationship between rainfall constancy and CAM dependence. We argue that higher CAM dependence might provide an adaptive advantage in increasingly unpredictable rainfall environments when the anatomic exaptation (succulence) is already present. These observations might shed light on the evolution of full CAM.
4 citations
18 May 2021
TL;DR: These patterns suggest that effective life history strategies for the arid-30 adapted species precludes the need for rhizobial mutualism, while the more “closed” N cycling in mesic savannas, and higher competitive stress, may favour nodulation, especially under low water supply that limits root access to soil nitrogen, and signals a more competitive environment and an advantage from N2-fixing.
Abstract:
Species in the genus Vachellia (Fabaceae) have a global tropical and sub-tropical distribution. Numerous Vachellia species are currently observed to be expanding their indigenous ranges and increasing in dominance globally, suggesting an overarching driver. Most Vachellia species enhance nitrogen uptake mutualistically via specialized root nodule structures. Nodules contain N2-fixing rhizobia that consume host supplied carbon to catalyse atmospheric N2 into a plant useable form, a key element in plant growth. The rhizobial mutualism of some Vachellia species may be vital to understanding changing patterns of ecological success observed across the savanna precipitation gradient. Here, we investigated how the seedling root development and physiology of two dominant savanna woody species, the arid-adapted Vachellia erioloba and the mesic-adapted Vachellia sieberiana, responded to simulated drought events. Seedlings of both species were grown at 4%, 8% and 16% soil moisture content (SMC) for four months. Seedling growth and allometry of arid-adapted V. erioloba was unresponsive to water stress treatments, and no nodulation was observed, reflecting a fixed higher relative investment in belowground biomass. In contrast, V. sieberiana roots were nodulated, but developed the highest nodule biomass and growth rate when grown at the lowest soil moisture (4% SMC). These patterns suggest that effective life history strategies for the arid-30 adapted species precludes the need for rhizobial mutualism, possibly due to more “open” N cycling and lower competitive interactions in arid systems, while the more “closed” N cycling in mesic savannas, and higher competitive stress, may favour nodulation, especially under low water supply that limits root access to soil nitrogen, and signals a more competitive environment and an advantage from N2-fixing.