N2O production pathways relate to land use type in acidic soils in subtropical China
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Agricultural practises impact soil properties and N transformation rate, and have a greater effect on N2O production pathways in agricultural soils compared with natural woodland soils. However, whether agricultural land use affects N2O production pathways in acidic soils in subtropical regions remains unknown.
Materials and methods
In this study, we collected natural woodland soil (WD) and three types of agricultural soils, namely upland agricultural (UA), tea plantation (TP) and bamboo plantation (BP) soils. We performed paired 15N-tracing experiment to investigate the effects of land use types on N2O production pathways in acidic soils in subtropical regions in China.
Results and discussion
The results revealed that heterotrophic nitrification is the dominant pathway of N2O production in WD, accounting for 44.6 % of N2O emissions, whereas heterotrophic nitrification contributed less than 2.7 % in all three agricultural soils, due to a lower organic C content and soil C/N ratio. In contrast, denitrification dominated N2O production in agricultural soils, accounting for 54.5, 72.8 and 77.1 % in UA, TP and BP, respectively. Nitrate (NO3 −) predominantly affected the contribution from denitrification in soils under different land use types. Autotrophic nitrification increased after the conversion of woodland to agricultural lands, peaking at 42.8 % in UA compared with only 21.5 % in WD, and was positively correlated with soil pH. Our data suggest that pH plays a great role in controlling N2O emissions through autotrophic nitrification following conversion of woodland to agricultural lands.
Our results demonstrate the variability in N2O production pathways in soils of different land use types. Soil pH, the quantity and quality of organic C and NO3 − content primarily determined N2O emissions. These results will likely assist modelling and mitigation of N2O emissions from different land use types in subtropical acidic soils in China and elsewhere.
KeywordsAgricultural soil Land use N2O production pathway Subtropical China Woodland soil
This work was supported by grants from the National Natural Science Foundation of China (41571227), the “973” Project (2014CB953803) and the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD, 164320H116).
- Cai Z, Zhao W (2009) Effects of land use types on nitrification in humid subtropical soils of China. Acta Pedol Sin 46:795–801 in Chinese with English abstractGoogle Scholar
- Davidson EA (1991) Fluxes of nitrous oxide and nitric oxide from terrestrial ecosystems. In: Rogers JE, Whitman WB (eds) Microbial production and consumption of greenhouse gases: methane, nitrogen oxides and halomethanes. American Society of Microbiology, Washington DC, pp. 219–235Google Scholar
- Ding C (2008) Oxidation–reduction regimes and characteristics of natural soil, upland soil and paddy soil in China. Acta Pedol Sin 45:66–75 in Chinese with English summaryGoogle Scholar
- Firestone M, Davidson E (1989) Microbiological basis of NO and N2O production and consumption in soil. In: Andreae M, Schimel D (eds) Exchange of trace gases between terrestrial ecosystems and the atmosphere. Wiley, Chichester, pp. 7–21Google Scholar
- IPCC, Ciais P, Sabine C, Bala G, Bopp L, Brovkin V, Canadell J, Chhabra A, DeFries R, Galloway J, Heimann, M, Jones C, Le Quéré C, Myneni RB, Piao S, Thornton P (2013) Carbon and other biogeochemical cycles. In: Stocker TF, Qin D, Plattner GK, Tignor M, Allen SK, Boschung J, Nauels A, Xia Y, Bex V, Midgley PM (eds) Climate Change 2013: the physical science basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USAGoogle Scholar
- Papen H, Berg VR, Hinkel I, Thoene B, Rennenberg H (1989) Heterotrophic nitrification by Alcaligenes faecalis: NO2, NO3 −, N2O, and NO production in exponentially growing cultures. Appl Environ Microbiol 55:2068–2072Google Scholar
- WMO (2015) The state of greenhouse gases in the atmosphere based on global observations through 2014. WMO Greenhouse Gas Bulletin 11:1–4Google Scholar
- Zaman M, Di HJ, Cameron KC, Frampton CM (1999) Gross nitrogen mineralization and nitrification rates and their relationships to enzyme activities and the soil microbial biomass in soils treated with dairy shed effluent and ammonium fertilizer at different water potentials. Biol Fertil Soils 29:178–186CrossRefGoogle Scholar
- Zhang J, Cai Z, Zhu T, Müller C (2013) Mechanisms for the retention of inorganic N in acidic forest soils of southern China. Scientific Reports 3:2342–2350Google Scholar
- Zhao Q (2002) Material cycling and regulation in red soils of China. Science Press, Beijing (in Chinese)Google Scholar