Surrounding species diversity improves subtropical seedlings’ carbon dynamics

Yann Salmon, Xuefei Li, Bo Yang, Keping Ma, Rolf T. W. Siegwolf, Bernhard Schmid

Tutkimustuotos: ArtikkelijulkaisuArtikkeliTieteellinenvertaisarvioitu

Kuvaus

Increasing biodiversity has been linked to higher primary productivity in terrestrial ecosystems. However, the underlying ecophysiological mechanisms remain poorly understood. We investigated the effects of surrounding species richness (monoculture, two- and four-species mixtures) on the ecophysiology of Lithocarpus glaber seedlings in experimental plots in subtropical China. A natural rain event isotopically labelled both the water uptaken by the L.glaber seedlings and the carbon in new photoassimilates through changes of photosynthetic discrimination. We followed the labelled carbon (C) and oxygen (O) in the plant-soil-atmosphere continuum. We measured gas-exchange variables (C assimilation, transpiration and above- and belowground respiration) and C-13 in leaf biomass, phloem, soil microbial biomass, leaf- and soil-respired CO2 as well as O-18 in leaf and xylem water. The C-13 signal in phloem and respired CO2 in L.glaber in monoculture lagged behind those in species mixture, showing a slower transport of new photoassimilates to and through the phloem in monoculture. Furthermore, leaf-water O-18 enrichment above the xylem water in L.glaber increased after the rain in lower diversity plots suggesting a lower ability to compensate for increased transpiration. Lithocarpus glaber in monoculture showed higher C assimilation rate and water-use efficiency. However, these increased C resources did not translate in higher growth of L.glaber in monoculture suggesting the existence of larger nongrowth-related C sinks in monoculture. These ecophysiological responses of L.glaber, in agreement with current understanding of phloem transport are consistent with a stronger competition for water resources in monoculture than in species mixtures. Therefore, increasing species diversity in the close vicinity of the studied plants appears to alleviate physiological stress induced by water competition and to counterbalance the negative effects of interspecific competition on assimilation rates for L.glaber by allowing a higher fraction of the C assimilated to be allocated to growth in species mixture than in monoculture.
Alkuperäiskielienglanti
LehtiEcology and Evolution
Vuosikerta8
Numero14
Sivut7055-7067
Sivumäärä13
ISSN2045-7758
DOI - pysyväislinkit
TilaJulkaistu - heinäkuuta 2018
OKM-julkaisutyyppiA1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä, vertaisarvioitu

Tieteenalat

  • 1172 Ympäristötiede

Lainaa tätä

Salmon, Yann ; Li, Xuefei ; Yang, Bo ; Ma, Keping ; Siegwolf, Rolf T. W. ; Schmid, Bernhard. / Surrounding species diversity improves subtropical seedlings’ carbon dynamics. Julkaisussa: Ecology and Evolution. 2018 ; Vuosikerta 8, Nro 14. Sivut 7055-7067.
@article{bb15e083b08a4d2b8ccaddb64b707b34,
title = "Surrounding species diversity improves subtropical seedlings’ carbon dynamics",
abstract = "Increasing biodiversity has been linked to higher primary productivity in terrestrial ecosystems. However, the underlying ecophysiological mechanisms remain poorly understood. We investigated the effects of surrounding species richness (monoculture, two- and four-species mixtures) on the ecophysiology of Lithocarpus glaber seedlings in experimental plots in subtropical China. A natural rain event isotopically labelled both the water uptaken by the L.glaber seedlings and the carbon in new photoassimilates through changes of photosynthetic discrimination. We followed the labelled carbon (C) and oxygen (O) in the plant-soil-atmosphere continuum. We measured gas-exchange variables (C assimilation, transpiration and above- and belowground respiration) and C-13 in leaf biomass, phloem, soil microbial biomass, leaf- and soil-respired CO2 as well as O-18 in leaf and xylem water. The C-13 signal in phloem and respired CO2 in L.glaber in monoculture lagged behind those in species mixture, showing a slower transport of new photoassimilates to and through the phloem in monoculture. Furthermore, leaf-water O-18 enrichment above the xylem water in L.glaber increased after the rain in lower diversity plots suggesting a lower ability to compensate for increased transpiration. Lithocarpus glaber in monoculture showed higher C assimilation rate and water-use efficiency. However, these increased C resources did not translate in higher growth of L.glaber in monoculture suggesting the existence of larger nongrowth-related C sinks in monoculture. These ecophysiological responses of L.glaber, in agreement with current understanding of phloem transport are consistent with a stronger competition for water resources in monoculture than in species mixtures. Therefore, increasing species diversity in the close vicinity of the studied plants appears to alleviate physiological stress induced by water competition and to counterbalance the negative effects of interspecific competition on assimilation rates for L.glaber by allowing a higher fraction of the C assimilated to be allocated to growth in species mixture than in monoculture.",
keywords = "1172 Environmental sciences, C-13, O-18, biodiversity, competition, photosynthesis, respiration, stable isotope, water, WATER-USE EFFICIENCY, DARK RESPIRED CO2, ISOTOPE COMPOSITION, ORGANIC-MATTER, BIODIVERSITY EXPERIMENTS, FOREST ECOSYSTEMS, DIEL VARIATIONS, PLANT ECOLOGY, TIME-LAG, SOIL, C-13, O-18, biodiversity, competition, photosynthesis, respiration, stable isotope, water, WATER-USE EFFICIENCY, DARK RESPIRED CO2, ISOTOPE COMPOSITION, ORGANIC-MATTER, BIODIVERSITY EXPERIMENTS, FOREST ECOSYSTEMS, DIEL VARIATIONS, PLANT ECOLOGY, TIME-LAG, SOIL",
author = "Yann Salmon and Xuefei Li and Bo Yang and Keping Ma and Siegwolf, {Rolf T. W.} and Bernhard Schmid",
year = "2018",
month = "7",
doi = "10.1002/ece3.4225",
language = "English",
volume = "8",
pages = "7055--7067",
journal = "Ecology and Evolution",
issn = "2045-7758",
publisher = "Wiley",
number = "14",

}

Surrounding species diversity improves subtropical seedlings’ carbon dynamics. / Salmon, Yann; Li, Xuefei; Yang, Bo; Ma, Keping; Siegwolf, Rolf T. W.; Schmid, Bernhard.

julkaisussa: Ecology and Evolution, Vuosikerta 8, Nro 14, 07.2018, s. 7055-7067.

Tutkimustuotos: ArtikkelijulkaisuArtikkeliTieteellinenvertaisarvioitu

TY - JOUR

T1 - Surrounding species diversity improves subtropical seedlings’ carbon dynamics

AU - Salmon, Yann

AU - Li, Xuefei

AU - Yang, Bo

AU - Ma, Keping

AU - Siegwolf, Rolf T. W.

AU - Schmid, Bernhard

PY - 2018/7

Y1 - 2018/7

N2 - Increasing biodiversity has been linked to higher primary productivity in terrestrial ecosystems. However, the underlying ecophysiological mechanisms remain poorly understood. We investigated the effects of surrounding species richness (monoculture, two- and four-species mixtures) on the ecophysiology of Lithocarpus glaber seedlings in experimental plots in subtropical China. A natural rain event isotopically labelled both the water uptaken by the L.glaber seedlings and the carbon in new photoassimilates through changes of photosynthetic discrimination. We followed the labelled carbon (C) and oxygen (O) in the plant-soil-atmosphere continuum. We measured gas-exchange variables (C assimilation, transpiration and above- and belowground respiration) and C-13 in leaf biomass, phloem, soil microbial biomass, leaf- and soil-respired CO2 as well as O-18 in leaf and xylem water. The C-13 signal in phloem and respired CO2 in L.glaber in monoculture lagged behind those in species mixture, showing a slower transport of new photoassimilates to and through the phloem in monoculture. Furthermore, leaf-water O-18 enrichment above the xylem water in L.glaber increased after the rain in lower diversity plots suggesting a lower ability to compensate for increased transpiration. Lithocarpus glaber in monoculture showed higher C assimilation rate and water-use efficiency. However, these increased C resources did not translate in higher growth of L.glaber in monoculture suggesting the existence of larger nongrowth-related C sinks in monoculture. These ecophysiological responses of L.glaber, in agreement with current understanding of phloem transport are consistent with a stronger competition for water resources in monoculture than in species mixtures. Therefore, increasing species diversity in the close vicinity of the studied plants appears to alleviate physiological stress induced by water competition and to counterbalance the negative effects of interspecific competition on assimilation rates for L.glaber by allowing a higher fraction of the C assimilated to be allocated to growth in species mixture than in monoculture.

AB - Increasing biodiversity has been linked to higher primary productivity in terrestrial ecosystems. However, the underlying ecophysiological mechanisms remain poorly understood. We investigated the effects of surrounding species richness (monoculture, two- and four-species mixtures) on the ecophysiology of Lithocarpus glaber seedlings in experimental plots in subtropical China. A natural rain event isotopically labelled both the water uptaken by the L.glaber seedlings and the carbon in new photoassimilates through changes of photosynthetic discrimination. We followed the labelled carbon (C) and oxygen (O) in the plant-soil-atmosphere continuum. We measured gas-exchange variables (C assimilation, transpiration and above- and belowground respiration) and C-13 in leaf biomass, phloem, soil microbial biomass, leaf- and soil-respired CO2 as well as O-18 in leaf and xylem water. The C-13 signal in phloem and respired CO2 in L.glaber in monoculture lagged behind those in species mixture, showing a slower transport of new photoassimilates to and through the phloem in monoculture. Furthermore, leaf-water O-18 enrichment above the xylem water in L.glaber increased after the rain in lower diversity plots suggesting a lower ability to compensate for increased transpiration. Lithocarpus glaber in monoculture showed higher C assimilation rate and water-use efficiency. However, these increased C resources did not translate in higher growth of L.glaber in monoculture suggesting the existence of larger nongrowth-related C sinks in monoculture. These ecophysiological responses of L.glaber, in agreement with current understanding of phloem transport are consistent with a stronger competition for water resources in monoculture than in species mixtures. Therefore, increasing species diversity in the close vicinity of the studied plants appears to alleviate physiological stress induced by water competition and to counterbalance the negative effects of interspecific competition on assimilation rates for L.glaber by allowing a higher fraction of the C assimilated to be allocated to growth in species mixture than in monoculture.

KW - 1172 Environmental sciences

KW - C-13

KW - O-18

KW - biodiversity

KW - competition

KW - photosynthesis

KW - respiration

KW - stable isotope

KW - water

KW - WATER-USE EFFICIENCY

KW - DARK RESPIRED CO2

KW - ISOTOPE COMPOSITION

KW - ORGANIC-MATTER

KW - BIODIVERSITY EXPERIMENTS

KW - FOREST ECOSYSTEMS

KW - DIEL VARIATIONS

KW - PLANT ECOLOGY

KW - TIME-LAG

KW - SOIL

KW - C-13

KW - O-18

KW - biodiversity

KW - competition

KW - photosynthesis

KW - respiration

KW - stable isotope

KW - water

KW - WATER-USE EFFICIENCY

KW - DARK RESPIRED CO2

KW - ISOTOPE COMPOSITION

KW - ORGANIC-MATTER

KW - BIODIVERSITY EXPERIMENTS

KW - FOREST ECOSYSTEMS

KW - DIEL VARIATIONS

KW - PLANT ECOLOGY

KW - TIME-LAG

KW - SOIL

U2 - 10.1002/ece3.4225

DO - 10.1002/ece3.4225

M3 - Article

VL - 8

SP - 7055

EP - 7067

JO - Ecology and Evolution

JF - Ecology and Evolution

SN - 2045-7758

IS - 14

ER -