Limits...
Effects of Warming on CO2 Fluxes in an Alpine Meadow Ecosystem on the Central Qinghai-Tibetan Plateau.

Ganjurjav H, Gao Q, Zhang W, Liang Y, Li Y, Cao X, Wan Y, Li Y, Danjiu L - PLoS ONE (2015)

Bottom Line: The GEP was more sensitive to climate variations than was the ER, resulting in a large increase in net carbon uptake under warming in the alpine meadow.The seasonal dynamic patterns of GEP and NEE, but not ER, were significantly impacted by warming.The effect of warming on inter- and intra-annual patterns of ecosystem CO2 fluxes and the mechanism of different sensitivities in GEP and ER to warming, require further researched.

View Article: PubMed Central - PubMed

Affiliation: Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China; Key Laboratory for Agro-Environment & Climate Change, Ministry of Agriculture, Beijing, China.

ABSTRACT
To analyze CO2 fluxes under conditions of climate change in an alpine meadow on the central Qinghai-Tibetan Plateau, we simulated the effect of warming using open top chambers (OTCs) from 2012 to 2014. The OTCs increased soil temperature by 1.62°C (P < 0.05), but decreased soil moisture (1.38%, P < 0.05) during the experiments. The response of ecosystem CO2 fluxes to warming was variable, and dependent on the year. Under conditions of warming, mean gross ecosystem productivity (GEP) during the growing season increased significantly in 2012 and 2014 (P < 0.05); however, ecosystem respiration (ER) increased substantially only in 2012 (P < 0.05). The net ecosystem CO2 exchange (NEE) increased marginally in 2012 (P = 0.056), did not change in 2013(P > 0.05), and increased significantly in 2014 (P = 0.034) under conditions of warming. The GEP was more sensitive to climate variations than was the ER, resulting in a large increase in net carbon uptake under warming in the alpine meadow. Under warming, the 3-year averages of GEP, ER, and NEE increased by 19.6%, 15.1%, and 21.1%, respectively. The seasonal dynamic patterns of GEP and NEE, but not ER, were significantly impacted by warming. Aboveground biomass, particularly the graminoid biomass increased significantly under conditions of warming. Soil moisture, soil temperature, and aboveground biomass were the main factors that affected the variation of the ecosystem CO2 fluxes. The effect of warming on inter- and intra-annual patterns of ecosystem CO2 fluxes and the mechanism of different sensitivities in GEP and ER to warming, require further researched.

No MeSH data available.


Related in: MedlinePlus

Temporal patterns of soil temperature and soil moisture in control and treatment plots in alpine meadow.C: Control, W: Warming. (a): Intra-annual patterns of soil temperature; (b) Intra-annual patterns of soil moisture; the dotted line indicate the period of spring drought in each year; (c): Inter-annual patterns of soil temperature; (d): Inter-annual patterns of soil moisture.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4492951&req=5

pone.0132044.g001: Temporal patterns of soil temperature and soil moisture in control and treatment plots in alpine meadow.C: Control, W: Warming. (a): Intra-annual patterns of soil temperature; (b) Intra-annual patterns of soil moisture; the dotted line indicate the period of spring drought in each year; (c): Inter-annual patterns of soil temperature; (d): Inter-annual patterns of soil moisture.

Mentions: The microclimate in each plot in the alpine meadow showed similar seasonal patterns during the growing seasons of 2012–2014 (Fig 1a and 1b). During the study period (from May 2012 to September 2014), the daily mean soil temperature in the treatment plots was significantly higher than in the control plot, being higher by 1.27°C, 2.09°C, and 1.52°C during the 2012, 2013, and 2014 growing seasons, respectively. The OTCs increased the daily mean soil temperature by an average of 1.62°C (P<0.05, Fig 1c) over the three years. Compared to the control plots, the soil moisture of the treatment plots reduced by 1.71%, 1.61%, and 0.83% in the 2012, 2013, and 2014 growing seasons, respectively. Thus, the average annual decrease in soil moisture caused by the OTCs was 1.38% (P<0.05, Fig 1d).


Effects of Warming on CO2 Fluxes in an Alpine Meadow Ecosystem on the Central Qinghai-Tibetan Plateau.

Ganjurjav H, Gao Q, Zhang W, Liang Y, Li Y, Cao X, Wan Y, Li Y, Danjiu L - PLoS ONE (2015)

Temporal patterns of soil temperature and soil moisture in control and treatment plots in alpine meadow.C: Control, W: Warming. (a): Intra-annual patterns of soil temperature; (b) Intra-annual patterns of soil moisture; the dotted line indicate the period of spring drought in each year; (c): Inter-annual patterns of soil temperature; (d): Inter-annual patterns of soil moisture.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4492951&req=5

pone.0132044.g001: Temporal patterns of soil temperature and soil moisture in control and treatment plots in alpine meadow.C: Control, W: Warming. (a): Intra-annual patterns of soil temperature; (b) Intra-annual patterns of soil moisture; the dotted line indicate the period of spring drought in each year; (c): Inter-annual patterns of soil temperature; (d): Inter-annual patterns of soil moisture.
Mentions: The microclimate in each plot in the alpine meadow showed similar seasonal patterns during the growing seasons of 2012–2014 (Fig 1a and 1b). During the study period (from May 2012 to September 2014), the daily mean soil temperature in the treatment plots was significantly higher than in the control plot, being higher by 1.27°C, 2.09°C, and 1.52°C during the 2012, 2013, and 2014 growing seasons, respectively. The OTCs increased the daily mean soil temperature by an average of 1.62°C (P<0.05, Fig 1c) over the three years. Compared to the control plots, the soil moisture of the treatment plots reduced by 1.71%, 1.61%, and 0.83% in the 2012, 2013, and 2014 growing seasons, respectively. Thus, the average annual decrease in soil moisture caused by the OTCs was 1.38% (P<0.05, Fig 1d).

Bottom Line: The GEP was more sensitive to climate variations than was the ER, resulting in a large increase in net carbon uptake under warming in the alpine meadow.The seasonal dynamic patterns of GEP and NEE, but not ER, were significantly impacted by warming.The effect of warming on inter- and intra-annual patterns of ecosystem CO2 fluxes and the mechanism of different sensitivities in GEP and ER to warming, require further researched.

View Article: PubMed Central - PubMed

Affiliation: Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China; Key Laboratory for Agro-Environment & Climate Change, Ministry of Agriculture, Beijing, China.

ABSTRACT
To analyze CO2 fluxes under conditions of climate change in an alpine meadow on the central Qinghai-Tibetan Plateau, we simulated the effect of warming using open top chambers (OTCs) from 2012 to 2014. The OTCs increased soil temperature by 1.62°C (P < 0.05), but decreased soil moisture (1.38%, P < 0.05) during the experiments. The response of ecosystem CO2 fluxes to warming was variable, and dependent on the year. Under conditions of warming, mean gross ecosystem productivity (GEP) during the growing season increased significantly in 2012 and 2014 (P < 0.05); however, ecosystem respiration (ER) increased substantially only in 2012 (P < 0.05). The net ecosystem CO2 exchange (NEE) increased marginally in 2012 (P = 0.056), did not change in 2013(P > 0.05), and increased significantly in 2014 (P = 0.034) under conditions of warming. The GEP was more sensitive to climate variations than was the ER, resulting in a large increase in net carbon uptake under warming in the alpine meadow. Under warming, the 3-year averages of GEP, ER, and NEE increased by 19.6%, 15.1%, and 21.1%, respectively. The seasonal dynamic patterns of GEP and NEE, but not ER, were significantly impacted by warming. Aboveground biomass, particularly the graminoid biomass increased significantly under conditions of warming. Soil moisture, soil temperature, and aboveground biomass were the main factors that affected the variation of the ecosystem CO2 fluxes. The effect of warming on inter- and intra-annual patterns of ecosystem CO2 fluxes and the mechanism of different sensitivities in GEP and ER to warming, require further researched.

No MeSH data available.


Related in: MedlinePlus