Simulated acid rain changed the proportion of heterotrophic respiration in soil respiration in a subtropical secondary forest

AbstractAcid rain has been regarded as a global environmental concern due to its negative effects on global ecosystems. In this study, we investigated the effects of simulated acid rain (SAR) on soil respiration rate and soil bacterial diversity in a Moso bamboo (phyllostachyspubescens) forest in subtropical China. Experimental results showed a similar seasonal pattern of soil respiration rates underdifferent SAR treatments. Seasonal mean soil respiration rates for CK (control, deionized water, pH 6.7), T1 (pH 5.6), T2 (pH 4.0) and T3 (pH 2.5) treatments were 3.44, 4.80, 4.35 and 4.51 μ mol m−2s−1, respectively. One-way analysis of variance indicated that the SAR exposure had no significant effect on soil respiration (p>0.1) and soil microbial biomass (p>0.1). Soil bacterial community diversity was calculated as the Shannon-Wiener diversity index and the results showed that only T3 treatment had significant effects on soil bacterial diversity. The DGGE analysis results revealed that T1 and CK soils had closer association and were related to the T2 soil, while T3 soil was distinctly different from the other treatments. This work highlights that the effects of SAR are important to consider in assessing the soil respiration rate, particularly under the scenario of increasing acid rain pollution.

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Impact of simulated acid rain on the composition of soil microbial communities and soil respiration in typical subtropical forests in Southwest China

Ecotoxicology and Environmental Safety ◽

10.1016/j.ecoenv.2021.112152 ◽

2021 ◽

Vol 215 ◽

pp. 112152

Author(s):

Yifan Li ◽

Yunqi Wang ◽

Weiqiang Zhang

Keyword(s):

Soil Respiration ◽

Microbial Communities ◽

Acid Rain ◽

Southwest China ◽

Soil Microbial Communities ◽

Simulated Acid Rain ◽

Subtropical Forests ◽

Soil Microbial

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Effects of Simulated Acid Rain on Soil Respiration of Pinus massoniana

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.295-298.249 ◽

2013 ◽

Vol 295-298 ◽

pp. 249-254 ◽

Cited By ~ 1

Author(s):

Nan Wang ◽

Shang Bin Bai

Keyword(s):

Soil Respiration ◽

Soil Temperature ◽

Acid Rain ◽

Control Level ◽

Pinus Massoniana ◽

Sensitivity Coefficient ◽

Simulated Acid Rain ◽

Regression Equations ◽

The Mean ◽

The Impact

In order to understand the impact of acid rain on soil respiration of P. Massoniana, a field study with 3 simulated acid rain levels (pH2. 5, 4. 0 and 6. 0) were conducted. Measurement of soil respiration was made using a LI-8100 soil CO2 emission system, the soil temperature at 10 cm depth also was recorded. Results show that: (1) The soil respiration of P. Massoniana under different acid rain levels fluctuated with distinct seasonal patterns and the soil respiration rate was influenced significantly by soil temperature. The mean rate of soil respiration under pH2.5 level were 1.79μmol m-2s-1, and increased 16% under control level (pH6.0) respectively. The mean rate of root respiration under pH2.5 level were 1.03μmol m-2s-1, and increased 12% under control level (pH6.0) respectively.(2) Significant relationships between soil respiration and soil temperature at 10 cm under different acid rain levels of P. massoniana found, which could be best described by exponential equations. The regression equations had more predicative capability than those using only temperature as a single independent variable. (3) The Q10 (temperature sensitivity coefficient of soil respiration) values at pH2.5, 4.0 levels of P. Massoniana were 1.40, 2.05, respectively. Compared with which at control level, the Q10 values tended to increase.

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Different responses of soil respiration and its components to nitrogen and phosphorus addition in a subtropical secondary forest

Forest Ecosystems ◽

10.1186/s40663-021-00313-z ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Junjun Zhang ◽

Yong Li ◽

Jinsong Wang ◽

Weinan Chen ◽

Dashuan Tian ◽

...

Keyword(s):

Soil Respiration ◽

Nitrogen Availability ◽

Secondary Forest ◽

Microbial Community Composition ◽

Nitrogen And Phosphorus ◽

Soil Nitrogen Availability ◽

Biogeochemical Models ◽

Subtropical Secondary Forest ◽

Co Addition ◽

P Addition

Abstract Background Nitrogen (N) and phosphorus (P) deposition have largely affected soil respiration (Rs) in forest ecosystems. However, few studies have explored how N and P individually or in combination to influence Rs and its components (autotrophic respiration, Ra; heterotrophic respiration, Rh), especially in highly P-limited subtropical forests. To address this question, we conducted a field manipulation experiment with N and/or P addition in a 50-year-old subtropical secondary forest. Results We found that N addition on average reduced Rs, Ra, and Rh by 15.2%, 15%, and 11.7%, respectively during 2-year field study. P addition had an inconsistent effect on Ra, with Ra increasing by 50.5% in the first year but reducing by 26.6% in the second year. Moreover, P addition on average decreased Rh by 8.9%–30.9% and Rs by 6.7%–15.6% across 2 years. In contrast, N and P co-addition on average increased Rs, Ra, and Rh by 1.9%, 7.9%, and 2.1% during the experimental period. Though Rs and Rh were significantly correlated with soil temperature, their temperature sensitivities were not significantly changed by fertilization. Ra was predominantly regulated by soil nitrogen availability (NH4+ and NO3−), soil dissolved organic carbon (DOC), and enzyme activities, while the variation in Rh was mainly attributable to changes in soil microbial community composition and soil β-D-Cellubiosidase (CB) and β-Xylosidase (XYL) activities. Conclusion Our findings highlight the contrasting responses of Rs and its components to N or P addition against N and P co-addition, which should be differentially considered in biogeochemical models in order to improve prediction of forest carbon dynamics in the context of N and P enrichment in terrestrial ecosystems.

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