Effects of nitrogen addition on soil respiration of Rhododendron simsii shrubland in the subtropical mountainous areas of China

doi:10.17521/cjpe.2015.0302

Abstract

Abstract:

Aims As the second largest C flux between the atmosphere and terrestrial ecosystems, soil respiration plays a vital role in regulating atmosphere CO₂ concentration. Therefore, understanding the response of soil respiration to the increasing nitrogen deposition is urgently needed for prediction of future climate change. However, it is still unclear how nitrogen deposition influences soil respiration of shrubland in subtropical China. Our objectives were to explore the effects of different levels of nitrogen fertilization on soil respiration, root biomass increment, and litter biomass, and to analyze the relationships between soil respiration and soil temperature and moisture.
Methods From January 2013 to September 2014, we conducted a short-term simulated nitrogen deposition experiment in the Rhododendron simsii shrubland of Dawei Mountain, located in Hunan Province, southern China. Four levels of nitrogen addition treatments (each level with three replicates) were established: control (CK, no nitrogen addition), low nitrogen addition (LN, 2 g·m^-2·a^-1), medium nitrogen addition (MN, 5 g·m^-2·a^-1) and high nitrogen addition (HN, 10 g·m^-2·a^-1). Soil respiration was measured by LI-8100 soil CO₂ efflux system. At the same time, we measured root biomass increment and litter biomass in each plot.
Important findings Soil respiration exhibited a strong seasonal pattern, with the highest rates found in summer and the lowest rates in winter. Annual accumulative soil respiration rate in the CK, LN, MN and HN was (2.37 ± 0.39), (2.79 ± 0.42), (2.26 ± 0.38) and (2.30 ± 0.36) kg CO₂·m^-2, respectively. Annual mean soil respiration rate in the CK, LN, MN and HN was (1.71 ± 0.28), (2.01 ± 0.30), (1.63 ± 0.27) and (1.66 ± 0.26) μmol CO₂·m^-2·s^-1, respectively, and it was 17.25% higher in the LN treatment compared with CK (p = 0.06). The root biomass increment was increased by LN, MN, and HN treatments by 18.36%, 36.49% and 61.63%, respectively, compared to CK. The litter biomass was increased by LN, MN, and HN treatments by 35.87%, 22.17% and 15.35%, respectively, compared with CK. Soil respiration exhibited a significant exponential relationship with soil temperature (p < 0.01, R²is 0.77 to 0.82) and a significant linear relationship with soil moisture at the depth of 5 cm (p < 0.05, R²is 0.10 to 0.15). The temperature sensitivity (Q₁₀) value of CK, LN, MN and HN plots was 3.96, 3.60, 3.71 and 3.51, respectively. These results suggested that nitrogen addition promoted plant growth and decreased the temperature sensitivity of soil respiration. The increase of root biomass under N addition may be an important reason for the change of soil respiration in the study area.

http://jtp.cnki.net/bilingual/detail/html/ZWSB201701011

Key words: temperature sensitivity (Q10), soil temperature, soil moisture, root biomass, litter biomass

Qiang ZHANG, Jia-Xiang LI, Zong-Qiang XIE. Effects of nitrogen addition on soil respiration of Rhododendron simsii shrubland in the subtropical mountainous areas of China[J]. Chin J Plant Ecol, 2017, 41(1): 95-104.

Add to citation manager EndNote|Ris|BibTeX

URL: https://www.plant-ecology.com/EN/10.17521/cjpe.2015.0302

https://www.plant-ecology.com/EN/Y2017/V41/I1/95

Figures/Tables 7

Table 1 Soil physical and chemical properties at different depth (mean ± SE)

土壤深度 Soil depth (cm)	全碳 Total C (%)	全氮 Total N (%)	C:N	全磷 Total P (mg·g^-1)	pH	土壤容重 Soil bulk density (g·cm^-3)
0-10	4.22 ± 0.16^a	0.36 ± 0.01^a	11.63 ± 0.14^a	0.77 ± 0.02^a	5.11 ± 0.01^b	0.88 ± 0.01^b
10-20	2.72 ± 0.13^b	0.26 ± 0.01^b	10.42 ± 0.19^b	0.75 ± 0.02^a	5.17 ± 0.02^b	0.98 ± 0.02^a
20-30	2.03 ± 0.13^c	0.21 ± 0.01^c	9.48 ± 0.25^c	0.75 ± 0.03^a	5.31 ± 0.03^a	1.01 ± 0.03^a

Fig. 1 Seasonal variations of soil temperature and moisture (mean ± SE).

Fig. 2 Root biomass increment (A) and litter biomass (B) under different nitrogen treatments (mean ± SE). CK, LN, MN and HN stand for 0, 2, 5 and 10 g·m-2·a-1 nitrogen addition, respectively.

Fig. 3 Seasonal variations of soil respiration under different nitrogen treatments (mean ± SE). CK, LN, MN and HN stand for 0, 2, 5 and 10 g·m-2·a-1 nitrogen addition, respectively.

Fig. 4 Soil respiration rate in the growing season under different nitrogen treatments (mean ± SE). CK, LN, MN and HN stand for 0, 2, 5 and 10 g·m-2·a-1 nitrogen addition, respectively.

Fig. 5 Relationships between soil respiration rate and soil temperature at 5 cm soil depth under different nitrogen treatments. CK, LN, MN and HN stand for 0, 2, 5 and 10 g·m-2·a-1 nitrogen addition, respectively. Q10, temperature sensitivity.

Fig. 6 Relationships between soil respiration rate and soil moisture at 5 cm soil depth under different nitrogen treatments. CK, LN, MN and HN stand for 0, 2, 5 and 10 g·m-2·a-1 nitrogen addition, respectively.

References 59

[1]	Aber JD, Nadelhoffer KJ, Steudler P, Melillo JM (1989). Nitrogen saturation in northern forest ecosystems.Bioscience, 39, 378-386.
[2]	Bond-Lamberty B, Thomson A (2010). A global database of soil respiration data.Biogeosciences, 7, 1915-1926.
[3]	Bowden RD, Davidson E, Savage K, Arabia C, Steudler P (2004). Chronic nitrogen additions reduce total soil respiration and microbial respiration in temperate forest soils at the Harvard Forest.Forest Ecology and Management, 196, 43-56.
[4]	Burton AJ, Pregitzer KS, Crawford JN, Zogg GP, Zak DR (2004). Simulated chronic NO3- deposition reduces soil respiration in northern hardwood forests.Global Change Biology, 10, 1080-1091.
[5]	Craine JM, Wedin DA, Reich PB (2001). Grassland species effects on soil CO2 flux track the effects of elevated CO2 and nitrogen.New Phytologist, 150, 425-434.
[6]	Cusack DF, Silver WL, Torn MS, McDowell WH (2011). Effects of nitrogen additions on above- and below-ground carbon dynamics in two tropical forests.Biogeochemistry, 104, 203-225.
[7]	Davidson EA, Janssens IA (2006). Temperature sensitivity of soil carbon decomposition and feedbacks to climate change.Nature, 440, 165-173.
[8]	Denman KL, Brasseur G, Chidthaisong A, Ciais P, Cox PM, Dickinson RE, Hauglustaine D, Heinze C, Holland E, Jacob D, Lohmann U, amachandran S, da Silva Dias PL, Wofsy SC, Zhang X (2007). Couplings between changes in the climate system and biogeochemistry. In: Solomon S, Qin D, Manning M, Marquis M, Averyt K, Tignor MMB, Miller HLR, Chen Z eds. Climate Change 2007, The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. RCambridge University Press, Cambridge, UK.
[9]	Deng Q, Zhou G, Liu J, Liu S, Duan H, Zhang D (2010). Responses of soil respiration to elevated carbon dioxide and nitrogen addition in young subtropical forest ecosystems in China.Biogeosciences, 7, 315-328.
[10]	Dilustro JJ, Collins B, Duncan L, Crawford C (2005). Moisture and soil texture effects on soil CO2 efflux components in southeastern mixed pine forests.Forest Ecology and Management, 204, 85-95.
[11]	Duan HL, Liu JX, Deng Q, Chen XM, Zhang DQ (2009). Effects of elevated CO2 and N deposition on plant biomass accumulation and allocation in subtropical forest ecosystems: A mesocosm study.Journal of Plant Ecology (Chinese Version), 33, 570-579. (in Chinese with English abstract)[段洪浪, 刘菊秀, 邓琦, 陈小梅, 张德强 (2009). CO2浓度升高与氮沉降对南亚热带森林生态系统植物生物量积累及分配格局的影响. 植物生态学报, 33, 570-579.]
[12]	Egerton-Warburton L, Allen E (2000). Shifts in the diversity of arbuscular mycorrhizal fungi along an anthropogenic nitrogen gradient.Ecological Applications, 10, 484-496.
[13]	Elser JJ, Andersen T, Baron JS, Bergstroem A-K, Jansson M, Kyle M, Nydick KR, Steger L, Hessen DO (2009). Shifts in lake N:P stoichiometry and nutrient limitation driven by atmospheric nitrogen deposition.Science, 326, 835-837.
[14]	Fang H, Mo JM, Peng SL, Li ZA, Wang H (2007). Cumulative effects of nitrogen additions on litter decomposition in three tropical forests in southern China.Plant and Soil, 297, 233-242.
[15]	Forster P, Ramaswamy V, Artaxo P, Berntsen T, Betts R, Fahey DW, Haywood J, Lean J, Lowe DC, Myhre G, Nganga J, Prinn R, Raga G, Schulz M, van Dorland R (2007). Changes in atmospheric constituents and in radiative forcing. In: Solomon S, Qin D, Manning M, Marquis M, Averyt K, Tignor MMB, Miller HLR, Chen Z eds. Climate Change 2007, The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, UK.
[16]	Frey SD, Knorr M, Parrent JL, Simpson RT (2004). Chronic nitrogen enrichment affects the structure and function of the soil microbial community in temperate hardwood and pine forests.Forest Ecology and Management, 196, 159-171.
[17]	Gallo M, Amonette R, Lauber C, Sinsabaugh RL, Zak DR (2004). Microbial community structure and oxidative enzyme activity in nitrogen-amended north temperate forest soils.Microbial Ecology, 48, 218-229.
[18]	Han GX, Zhou GS (2009). Review of spatial and temporal variations of soil respiration and driving mechanisms.Chinese Journal of Plant Ecology, 33, 197-205. (in Chinese with English abstract)[韩广轩, 周广胜 (2009). 土壤呼吸作用时空动态变化及其影响机制研究与展望. 植物生态学报, 33, 197-205.]
[19]	Hanson PJ, Edwards NT, Garten CT, Andrews JA (2000). Separating root and soil microbial contributions to soil respiration: A review of methods and observations.Biogeochemistry, 48, 115-146.
[20]	Högberg P (2007). Environmental science: Nitrogen impacts on forest carbon.Nature, 447, 781-782.
[21]	Högberg P, Fan HB, Quist M, Binkley D, Tamm CO (2006). Tree growth and soil acidification in response to 30 years of experimental nitrogen loading on boreal forest.Global Change Biology, 12, 489-499.
[22]	Hu HF, Wang ZH, GH, Fu BJ (2006). Vegetation carbon storage of major shrublands in China.Journal of Plant Eco- logy (Chinese Version), 30, 539-544. (in Chinese with English abstract)[胡会峰, 王志恒, 刘国华, 傅伯杰 (2006). 中国主要灌丛植被碳储量. 植物生态学报, 30, 539-544.]
[23]	Hyvonen R, Agren GI, Linder S, Persson T, Cotrufo MF, Ekblad A, Freeman M, Grelle A, Janssens IA, Jarvis PG, Kellomaki S, Lindroth A, Loustau D, Lundmark T, Norby RJ, Oren R, Pilegaard K, Ryan MG, Sigurdsson BD, Stromgren M, van Oijen M, Wallin G (2007). The likely impact of elevated CO2, nitrogen deposition, increased temperature and management on carbon sequestration in temperate and boreal forest ecosystems: A literature review.New Phytologist, 173, 463-480.
[24]	Hyvonen R, Persson T, Andersson S, Olsson B, Agren GI, Linder S (2008). Impact of long-term nitrogen addition on carbon stocks in trees and soils in northern Europe.Biogeochemistry, 89, 121-137.
[25]	IPCC (Intergovernmental Panel on Climate Change) (2013). Contribution of working group 1 to the fifth assessment report of the intergovernmental panel on climate change. In: Stocker TF, Qin DH, Plattner GK, Tignor MMB, Allen SK, Boschung J, Nauels A, Xia Y, Bex V, Midgley PM eds. Climate Change 2013: The Physical Science Basis. Cambridge University Press, Cambridge, UK.
[26]	Janssens IA, Dieleman W, Luyssaert S, Subke JA, Reichstein M, Ceulemans R, Ciais P, Dolman AJ, Grace J, Matteucci G, Papale D, Piao SL, Schulze ED, Tang J, Law BE (2010). Reduction of forest soil respiration in response to nitrogen deposition.Nature Geoscience, 3, 315-322.
[27]	Knorr M, Frey SD, Curtis PS (2005). Nitrogen additions and litter decomposition: A meta-analysis.Ecology, 86, 3252-3257.
[28]	LeBauer DS, Treseder KK (2008). Nitrogen limitation of net primary productivity in terrestrial ecosystems is globally distributed.Ecology, 89, 371-379.
[29]	Li JX, Zhang X, Xie ZQ, Lu CF, Tu XY, Xun Y (2015). Community composition and structure ofRhododendron simsii shrubland in the Dawei Mountain, Hunan Province. Biodiversity Science, 23, 815-823. (in Chinese with English abstract)[李家湘, 张旭, 谢宗强, 卢从发, 涂向阳, 寻院 (2015). 湖南大围山杜鹃灌丛的群落组成及结构特征. 生物多样性, 23, 815-823.]
[30]	Liu X, Duan L, Mo J, Du E, Shen J, Lu X, Zhang Y, Zhou X, He C, Zhang F (2011). Nitrogen deposition and its ecological impact in China: An overview.Environmental Pollution, 159, 2251-2264.
[31]	Lue CQ, Tian HQ (2007). Spatial and temporal patterns of nitrogen deposition in China: Synthesis of observational data. Journal of Geophysical Research-Atmospheres, 112, D22S05, doi: 10.1029/2006JD007990.
[32]	Luo L, Sheng GZ, Xie ZQ, Zhou LG (2011). Components of soil respiration and its temperature sensitivity in four types of forests along an elevational gradient in Shennongjia, China.Chinese Journal of Plant Ecology, 35, 722-730. (in Chinese with English abstract)[罗璐, 申国珍, 谢宗强, 周利光 (2011). 神农架海拔梯度上4种典型森林的土壤呼吸组分及其对温度的敏感性. 植物生态学报, 35, 722-730.]
[33]	Luo YQ, Hui DF, Zhang DQ (2006). Elevated CO2 stimulates net accumulations of carbon and nitrogen in land ecosystems: A meta-analysis.Ecology, 87, 53-63.
[34]	Ma YC, Zhu B, Sun ZZ, Zhao C, Yang Y, Piao SL (2014). The effects of simulated nitrogen deposition on extracellular enzyme activities of litter and soil among different-aged stands of larch.Journal of Plant Ecology, 7, 240-249.
[35]	Maskell LC, Smart SM, Bullock JM, Thompson K, Stevens CJ (2010). Nitrogen deposition causes widespread loss of species richness in British habitats.Global Change Biology, 16, 671-679.
[36]	Melillo JM, Steudler PA, Aber JD, Newkirk K, Lux H, Bowles FP, Catricala C, Magill A, Ahrens T, Morrisseau S (2002). Soil warming and carbon-cycle feedbacks to the climate system.Science, 298, 2173-2176.
[37]	Mo JM, Brown S, Xue JH, Fang YT, Li ZA (2006).Response of litter decomposition to simulated N deposition in disturbed, rehabilitated and mature forests in subtropical China. Plant and Soil, 282, 135-151.
[38]	Mo JM, Zhang W, Zhu WX, Fang YT, Li DJ, Zhao P (2007). Response of soil respiration to simulated N deposition in a disturbed and a rehabilitated tropical forest in southern China.Plant and Soil, 296, 125-135.
[39]	Mo JM, Zhang W, Zhu WX, Gundersen P, Fang YT, Li DJ, Wang H (2008). Nitrogen addition reduces soil respiration in a mature tropical forest in southern China.Global Change Biology, 14, 403-412.
[40]	Moscatelli MC, Lagornarsino A, de Angelis P, Grego S (2008). Short and mediumterm contrasting effects of nitrogen fertilization on C and N cycling in a poplar plantation soil.Forest Ecology and Management, 255, 447-454.
[41]	Pendall E, Bridgham S, Hanson PJ, Hungate B, Kicklighter DW, Johnson DW, Law BE, Luo YQ, Megonigal JP, Olsrud M, Ryan MG, Wan SQ (2004). Belowground process responses to elevated CO2 and temperature: A discussion of observations, measurement methods, and models.New Phytologist, 162, 311-322.
[42]	Peng SS, Piao SL, Wang T, Sun JY, Shen ZH (2009). Temperature sensitivity of soil respiration in different ecosystems in China.Soil Biology & Biochemistry, 41, 1008-1014.
[43]	Pregitzer KS, Burton AJ, Zak DR, Talhelm AF (2008). Simulated chronic nitrogen deposition increases carbon storage in northern temperate forests.Global Change Biology, 14, 142-153.
[44]	Raich JW, Potter CS, Bhagawati D (2002). Interannual varia- bility in global soil respiration, 1980-1994.Global Change Biology, 8, 800-812.
[45]	Rodeghiero M, Cescatti A (2006). Indirect partitioning of soil respiration in a series of evergreen forest ecosystems.Plant and Soil, 284, 7-22.
[46]	Rühling Å, Tyler G (1991). Effects of simulated nitrogen deposition to the forest floor on the macrofungal flora of a beech forest.Ambio, 20, 261-263.
[47]	Ryan MG, Law BE (2005). Interpreting, measuring, and modeling soil respiration.Biogeochemistry, 73, 3-27.
[48]	Schlesinger WH, Andrews JA (2000). Soil respiration and the global carbon cycle.Biogeochemistry, 48, 7-20.
[49]	Sotta ED, Meir P, Malhi Y, Nobre AD, Hodnett M, Grace J (2004). Soil CO2 efflux in a tropical forest in the central Amazon.Global Change Biology, 10, 601-617.
[50]	Sun ZZ, Liu LL, Ma YC, Yin GD, Zhao C, Zhang Y, Piao SL (2014). The effect of nitrogen addition on soil respiration from a nitrogen-limited forest soil.Agricultural and Forest Meteorology, 197, 103-110.
[51]	Tang XL, Liu SG, Zhou GY, Zhang DQ, Zhou CY (2006). Soil-atmospheric exchange of CO2, CH4, and N2O in three subtropical forest ecosystems in southern China.Global Change Biology, 12, 546-560.
[52]	Tarnocai C, Canadell JG, Schuur EAG, Kuhry P, Mazhitova G, Zimov S (2009). Soil organic carbon pools in the northern circumpolar permafrost region. Global Biogeochemical Cycles, 23, GB2023, doi: 10.1029/2008GB003327.
[53]	Thomas RQ, Canham CD, Weathers KC, Goodale CL (2010). Increased tree carbon storage in response to nitrogen deposition in the US.Nature Geoscience, 3, 13-17.
[54]	Tu LH, Hu TX, Zhang J, Li XW, Hu HL, Liu L, Xiao YL (2013). Nitrogen addition stimulates different components of soil respiration in a subtropical bamboo ecosystem.Soil Biology & Biochemistry, 58, 255-264.
[55]	Xu WH, Wan SQ (2008). Water- and plant-mediated responses of soil respiration to topography, fire, and nitrogen fertilization in a semiarid grassland in northern China.Soil Biology & Biochemistry, 40, 679-687.
[56]	Zheng SW, Tang M, Zou JH, Mu CL (2007). Summary of research on shrub biomass in China.Journal of Chengdu University (Natural Science Edition), 26, 189-192. (in Chinese with English abstract)[郑绍伟, 唐敏, 邹俊辉, 慕长龙 (2007). 灌木群落及生物量研究综述. 成都大学学报(自然科学版), 26, 189-192.]
[57]	Zheng XH, Fu CB, Xu XK, Yan XD, Huang Y, Han SH, Hu F, Chen GX (2002). The Asian nitrogen cycle case study.AMBIO, 31, 79-87.
[58]	Zheng ZM, Yu GR, Fu YL, Wang YS, Sun XM, Wang YH (2009). Temperature sensitivity of soil respiration is affected by prevailing climatic conditions and soil organic carbon content: A trans-China based case study.Soil Biology & Biochemistry, 41, 1531-1540.
[59]	Zhou LY, Zhou XH, Zhang BC, Lu M, Luo YQ, Liu LL, Li B (2014). Different responses of soil respiration and its components to nitrogen addition among biomes: A meta- analysis.Global Change Biology, 20, 2332-2343.