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Temporal-spatial variation and controls of soil respiration in different primary succession stages on glacier forehead in Gongga Mountain, China.

Luo J, Chen Y, Wu Y, Shi P, She J, Zhou P - PLoS ONE (2012)

Bottom Line: Our results showed that there was substantial temporal (coefficient of variation (CV) ranged from 39.3% to 73.9%) and spatial (CV ranged from 12.3% to 88.6%) variation in SR.Q(10) values (ranged from 2.1 to 4.7) increased along the forest succession, and the mean value (3.3) was larger than that of temperate ecosystems, which indicated a general tendency towards higher-Q(10) in colder ecosystems than in warmer ecosystems.Our findings provided valuable information for understanding temporal-spatial variation and controlling factors of SR.

View Article: PubMed Central - PubMed

Affiliation: Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, China.

ABSTRACT
Soil respiration (SR) is an important process in the global carbon cycle. It is difficult to estimate SR emission accurately because of its temporal and spatial variability. Primary forest succession on Glacier forehead provides the ideal environment for examining the temporal-spatial variation and controlling factors of SR. However, relevant studies on SR are relatively scarce, and variations, as well as controlling factors, remain uncertain in this kind of region. In this study, we used a static chamber system to measure SR in six sites which represent different stages of forest succession on forehead of a temperate glacier in Gongga Mountain, China. Our results showed that there was substantial temporal (coefficient of variation (CV) ranged from 39.3% to 73.9%) and spatial (CV ranged from 12.3% to 88.6%) variation in SR. Soil temperature (ST) at 5 cm depth was the major controlling factor of temporal variation in all six sites. Spatial variation in SR was mainly caused by differences in plant biomass and Total N among the six sites. Moreover, soil moisture (SM), microbial biomass carbon (MBC), soil organic carbon (SOC), pH and bulk density could influence SR by directly or indirectly affecting plant biomass and Total N. Q(10) values (ranged from 2.1 to 4.7) increased along the forest succession, and the mean value (3.3) was larger than that of temperate ecosystems, which indicated a general tendency towards higher-Q(10) in colder ecosystems than in warmer ecosystems. Our findings provided valuable information for understanding temporal-spatial variation and controlling factors of SR.

Show MeSH
Relationship between SR and SM for six sites.SR and SM means soil respiration and soil moisture, respectively. The curves were fitted using equation
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pone-0042354-g005: Relationship between SR and SM for six sites.SR and SM means soil respiration and soil moisture, respectively. The curves were fitted using equation

Mentions: Significantly positive correlation between SR and SM could be found in all the six sites (p<0.001). The polynomial functions were found to provide the best fit for the relationship between SR and SM in this study (Fig. 5). The SM-based models could explain the temporal variation in SR from 12.3% for site 4 to 32.4% for site 2. Values of R2 here are smaller than the corresponding R2 value using ST-based exponential model (equation (1)) for corresponding plots. When both SM and ST are used as independent variables and fitted to equation (3), we did not find a significant increase in R2 as compared with those fitted using equation (1) for each site (Table 2).


Temporal-spatial variation and controls of soil respiration in different primary succession stages on glacier forehead in Gongga Mountain, China.

Luo J, Chen Y, Wu Y, Shi P, She J, Zhou P - PLoS ONE (2012)

Relationship between SR and SM for six sites.SR and SM means soil respiration and soil moisture, respectively. The curves were fitted using equation
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3412854&req=5

pone-0042354-g005: Relationship between SR and SM for six sites.SR and SM means soil respiration and soil moisture, respectively. The curves were fitted using equation
Mentions: Significantly positive correlation between SR and SM could be found in all the six sites (p<0.001). The polynomial functions were found to provide the best fit for the relationship between SR and SM in this study (Fig. 5). The SM-based models could explain the temporal variation in SR from 12.3% for site 4 to 32.4% for site 2. Values of R2 here are smaller than the corresponding R2 value using ST-based exponential model (equation (1)) for corresponding plots. When both SM and ST are used as independent variables and fitted to equation (3), we did not find a significant increase in R2 as compared with those fitted using equation (1) for each site (Table 2).

Bottom Line: Our results showed that there was substantial temporal (coefficient of variation (CV) ranged from 39.3% to 73.9%) and spatial (CV ranged from 12.3% to 88.6%) variation in SR.Q(10) values (ranged from 2.1 to 4.7) increased along the forest succession, and the mean value (3.3) was larger than that of temperate ecosystems, which indicated a general tendency towards higher-Q(10) in colder ecosystems than in warmer ecosystems.Our findings provided valuable information for understanding temporal-spatial variation and controlling factors of SR.

View Article: PubMed Central - PubMed

Affiliation: Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, China.

ABSTRACT
Soil respiration (SR) is an important process in the global carbon cycle. It is difficult to estimate SR emission accurately because of its temporal and spatial variability. Primary forest succession on Glacier forehead provides the ideal environment for examining the temporal-spatial variation and controlling factors of SR. However, relevant studies on SR are relatively scarce, and variations, as well as controlling factors, remain uncertain in this kind of region. In this study, we used a static chamber system to measure SR in six sites which represent different stages of forest succession on forehead of a temperate glacier in Gongga Mountain, China. Our results showed that there was substantial temporal (coefficient of variation (CV) ranged from 39.3% to 73.9%) and spatial (CV ranged from 12.3% to 88.6%) variation in SR. Soil temperature (ST) at 5 cm depth was the major controlling factor of temporal variation in all six sites. Spatial variation in SR was mainly caused by differences in plant biomass and Total N among the six sites. Moreover, soil moisture (SM), microbial biomass carbon (MBC), soil organic carbon (SOC), pH and bulk density could influence SR by directly or indirectly affecting plant biomass and Total N. Q(10) values (ranged from 2.1 to 4.7) increased along the forest succession, and the mean value (3.3) was larger than that of temperate ecosystems, which indicated a general tendency towards higher-Q(10) in colder ecosystems than in warmer ecosystems. Our findings provided valuable information for understanding temporal-spatial variation and controlling factors of SR.

Show MeSH