Elevated CO 2 interacts with nutrient inputs to restructure plant communities in phosphorus-limited grasslands.

Autor: Taylor CR; Soil and Ecosystem Ecology, Earth and Environmental Sciences, University of Manchester, Manchester, UK.; Plants, Photosynthesis and Soil, School of Biosciences, University of Sheffield, Sheffield, UK., England LC; Plants, Photosynthesis and Soil, School of Biosciences, University of Sheffield, Sheffield, UK., Keane JB; Plants, Photosynthesis and Soil, School of Biosciences, University of Sheffield, Sheffield, UK.; Department of Environment and Geography, Wentworth Way, University of York, Heslington, York, UK., Davies JAC; Lancaster Environment Centre, Lancaster University, Lancaster, UK., Leake JR; Plants, Photosynthesis and Soil, School of Biosciences, University of Sheffield, Sheffield, UK., Hartley IP; Geography, Faculty of Environment, Science and Economy, University of Exeter, Exeter, UK., Smart SM; UK Centre for Ecology & Hydrology, Lancaster, UK., Janes-Bassett V; Geography and Planning, School of Environmental Sciences, University of Liverpool, Liverpool, UK., Phoenix GK; Plants, Photosynthesis and Soil, School of Biosciences, University of Sheffield, Sheffield, UK.
Jazyk: angličtina
Zdroj: Global change biology [Glob Chang Biol] 2024 Jan; Vol. 30 (1), pp. e17104.
DOI: 10.1111/gcb.17104
Abstrakt: Globally pervasive increases in atmospheric CO 2 and nitrogen (N) deposition could have substantial effects on plant communities, either directly or mediated by their interactions with soil nutrient limitation. While the direct consequences of N enrichment on plant communities are well documented, potential interactions with rising CO 2 and globally widespread phosphorus (P) limitation remain poorly understood. We investigated the consequences of simultaneous elevated CO 2 (eCO 2 ) and N and P additions on grassland biodiversity, community and functional composition in P-limited grasslands. We exposed soil-turf monoliths from limestone and acidic grasslands that have received >25 years of N additions (3.5 and 14 g m -2  year -1 ) and 11 (limestone) or 25 (acidic) years of P additions (3.5 g m -2  year -1 ) to eCO 2 (600 ppm) for 3 years. Across both grasslands, eCO 2 , N and P additions significantly changed community composition. Limestone communities were more responsive to eCO 2 and saw significant functional shifts resulting from eCO 2 -nutrient interactions. Here, legume cover tripled in response to combined eCO 2 and P additions, and combined eCO 2 and N treatments shifted functional dominance from grasses to sedges. We suggest that eCO 2 may disproportionately benefit P acquisition by sedges by subsidising the carbon cost of locally intense root exudation at the expense of co-occurring grasses. In contrast, the functional composition of the acidic grassland was insensitive to eCO 2 and its interactions with nutrient additions. Greater diversity of P-acquisition strategies in the limestone grassland, combined with a more functionally even and diverse community, may contribute to the stronger responses compared to the acidic grassland. Our work suggests we may see large changes in the composition and biodiversity of P-limited grasslands in response to eCO 2 and its interactions with nutrient loading, particularly where these contain a high diversity of P-acquisition strategies or developmentally young soils with sufficient bioavailable mineral P.
(© 2024 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)
Databáze: MEDLINE
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