Limits...
Light and heavy fractions of soil organic matter in response to climate warming and increased precipitation in a temperate steppe.

Song B, Niu S, Zhang Z, Yang H, Li L, Wan S - PLoS ONE (2012)

Bottom Line: Climate change profoundly affects soil C and N storage via changing C and N inputs and outputs.Experimental warming reduced soil labile C (LFC, MBC, and DOC).Our results indicate that certain soil carbon fraction is sensitive to climate change in the temperate steppe, which may in turn impact ecosystem carbon fluxes in response and feedback to climate change.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Xiangshan, Beijing, China.

ABSTRACT
Soil is one of the most important carbon (C) and nitrogen (N) pools and plays a crucial role in ecosystem C and N cycling. Climate change profoundly affects soil C and N storage via changing C and N inputs and outputs. However, the influences of climate warming and changing precipitation regime on labile and recalcitrant fractions of soil organic C and N remain unclear. Here, we investigated soil labile and recalcitrant C and N under 6 years' treatments of experimental warming and increased precipitation in a temperate steppe in Northern China. We measured soil light fraction C (LFC) and N (LFN), microbial biomass C (MBC) and N (MBN), dissolved organic C (DOC) and heavy fraction C (HFC) and N (HFN). The results showed that increased precipitation significantly stimulated soil LFC and LFN by 16.1% and 18.5%, respectively, and increased LFC:HFC ratio and LFN:HFN ratio, suggesting that increased precipitation transferred more soil organic carbon into the quick-decayed carbon pool. Experimental warming reduced soil labile C (LFC, MBC, and DOC). In contrast, soil heavy fraction C and N, and total C and N were not significantly impacted by increased precipitation or warming. Soil labile C significantly correlated with gross ecosystem productivity, ecosystem respiration and soil respiration, but not with soil moisture and temperature, suggesting that biotic processes rather than abiotic factors determine variations in soil labile C. Our results indicate that certain soil carbon fraction is sensitive to climate change in the temperate steppe, which may in turn impact ecosystem carbon fluxes in response and feedback to climate change.

Show MeSH

Related in: MedlinePlus

Linear correlations between GEP and light fraction C (a) or N (b), MBC (c) and DOC (d) across all the 24 subplots.GEP, gross ecosystem productivity, whose values were the yearly mean values from 2005 to 2009.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3316559&req=5

pone-0033217-g004: Linear correlations between GEP and light fraction C (a) or N (b), MBC (c) and DOC (d) across all the 24 subplots.GEP, gross ecosystem productivity, whose values were the yearly mean values from 2005 to 2009.

Mentions: Across all the 24 subplots, LFC showed a positive relationship with the yearly mean values of GEP (R2 = 0.26, p = 0.01; Fig. 4a), ER (R2 = 0.39, p<0.01; Fig. 5a) or SR (R2 = 0.42, p<0.01; Fig. 5b). Similarly, LFN showed a positive linear correlation with GEP (R2 = 0.28, p<0.01; Fig. 4b), ER (R2 = 0.42, p<0.01; Fig. 5c) or SR (R2 = 0.44, p<0.01; Fig. 5d). Moreover, MBC and DOC, also showed positive linear correlations with GEP, ER and SR, except that DOC had no significant correlation with GEP (p>0.05; Fig. 4, Fig. 6). No significant relationship of soil light or heavy fraction C or N was found with soil temperature or moisture across the 24 subplots (p>0.05).


Light and heavy fractions of soil organic matter in response to climate warming and increased precipitation in a temperate steppe.

Song B, Niu S, Zhang Z, Yang H, Li L, Wan S - PLoS ONE (2012)

Linear correlations between GEP and light fraction C (a) or N (b), MBC (c) and DOC (d) across all the 24 subplots.GEP, gross ecosystem productivity, whose values were the yearly mean values from 2005 to 2009.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3316559&req=5

pone-0033217-g004: Linear correlations between GEP and light fraction C (a) or N (b), MBC (c) and DOC (d) across all the 24 subplots.GEP, gross ecosystem productivity, whose values were the yearly mean values from 2005 to 2009.
Mentions: Across all the 24 subplots, LFC showed a positive relationship with the yearly mean values of GEP (R2 = 0.26, p = 0.01; Fig. 4a), ER (R2 = 0.39, p<0.01; Fig. 5a) or SR (R2 = 0.42, p<0.01; Fig. 5b). Similarly, LFN showed a positive linear correlation with GEP (R2 = 0.28, p<0.01; Fig. 4b), ER (R2 = 0.42, p<0.01; Fig. 5c) or SR (R2 = 0.44, p<0.01; Fig. 5d). Moreover, MBC and DOC, also showed positive linear correlations with GEP, ER and SR, except that DOC had no significant correlation with GEP (p>0.05; Fig. 4, Fig. 6). No significant relationship of soil light or heavy fraction C or N was found with soil temperature or moisture across the 24 subplots (p>0.05).

Bottom Line: Climate change profoundly affects soil C and N storage via changing C and N inputs and outputs.Experimental warming reduced soil labile C (LFC, MBC, and DOC).Our results indicate that certain soil carbon fraction is sensitive to climate change in the temperate steppe, which may in turn impact ecosystem carbon fluxes in response and feedback to climate change.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Xiangshan, Beijing, China.

ABSTRACT
Soil is one of the most important carbon (C) and nitrogen (N) pools and plays a crucial role in ecosystem C and N cycling. Climate change profoundly affects soil C and N storage via changing C and N inputs and outputs. However, the influences of climate warming and changing precipitation regime on labile and recalcitrant fractions of soil organic C and N remain unclear. Here, we investigated soil labile and recalcitrant C and N under 6 years' treatments of experimental warming and increased precipitation in a temperate steppe in Northern China. We measured soil light fraction C (LFC) and N (LFN), microbial biomass C (MBC) and N (MBN), dissolved organic C (DOC) and heavy fraction C (HFC) and N (HFN). The results showed that increased precipitation significantly stimulated soil LFC and LFN by 16.1% and 18.5%, respectively, and increased LFC:HFC ratio and LFN:HFN ratio, suggesting that increased precipitation transferred more soil organic carbon into the quick-decayed carbon pool. Experimental warming reduced soil labile C (LFC, MBC, and DOC). In contrast, soil heavy fraction C and N, and total C and N were not significantly impacted by increased precipitation or warming. Soil labile C significantly correlated with gross ecosystem productivity, ecosystem respiration and soil respiration, but not with soil moisture and temperature, suggesting that biotic processes rather than abiotic factors determine variations in soil labile C. Our results indicate that certain soil carbon fraction is sensitive to climate change in the temperate steppe, which may in turn impact ecosystem carbon fluxes in response and feedback to climate change.

Show MeSH
Related in: MedlinePlus