1. Jiangxi Key Laboratory for Restoration of Degraded Ecosystems & Watershed Ecohydrology, Nanchang Institute of Technology, Nanchang 330099, China;
2. School of Resources and Environment, Anhui Agricultural University, Hefei 230036, China
A laboratory experiment was set up to explore the influences of oil pollution and bacterial-feeding nematodes greenhouse gas emissions and soil microbial activities. There were 5 treatments in this experiment:soil (S) as the control,5.0g/kg oil contaminated soil (SP),5.0g/kg oil contaminated soil + 5 nematodes/g dry soil (SPN5),5.0g/kg oil contaminated soil + 10nematodes/g dry soil (SPN10),5.0g/kg oil contaminated soil + 20 nematodes/g dry soil (SPN20). Compared with the control, the emissions of CO2, N2O increased by 7.03~10.16 times, 11.56~32.19 times respectively in oil contaminated soil, and the emission of CH4 wasn't impacted obviously. The oil pollution has seriously aggravated the greenhouse effect judging by the dynamic of global warming potential (GWP), and greenhouse effect has increased by 7.13~10.17times compared with the control. Oil pollution and bacterial-feeding nematodes increased microbial biomass carbon and metabolic entropy (qCO2) to a certain extent, with the microbial biomass carbon increasing at first and then decreasing. Compared with the control, the metabolic entropy of other treatments was about 6.59~9.83 times higher. The fluorescein diacetate (FDA) hydrolysis activity was inhibited before being enhanced in oil contaminated soil. While the activities of soil invertase and urease were enhanced in oil contaminated soil. To some extent, the bacterial-feeding nematodes can promote soil enzyme activity, and affect the emissions of greenhouse gases, CO2, N2O, and CH4.
IPCC. Special Report on Emissions Scenarios:A special Report of Working Group Ⅲ of the Intergovernmental Panel on Climate Change[R]. Cambridge:Cambridge University Press, 2000.
Wu H, Lu M, Lu X, et al. Interactions between earthworms and mesofauna has no significanteffect on emissions of CO2 and N2O from soil[J]. Soil Biology & Biochemistry, 2015,88:294-297.
[15]
Thakur M P, van Groenigen J W, Kuiper I, et al. Interactions between microbial-feeding and predatory soil faunatrigger N2O emissions[J]. Soil Biology & Biochemistry, 2014,70:256-262.
[16]
Porre R J, van Groenigen J W, De Deyn G B, et al. Exploring the relationship between soil mesofauna, soil structure and N2O emissions[J]. Soil Biology & Biochemistry, 2016,96:55-64.
Ingham R E, Trofymow J A, Ingham E R, et al. Interactions of bacteria, fungi and their nematode grazers:effects on nutrient cycling and plant growth[J]. Ecological Monographs, 1985,55:119-140.
[33]
Fu S L, Ferris H, Brown D, et al. Does the positive feedback effect of nematodes on the biomass and activity of their bacteria prey vary with nematode species and population size[J]. Soil Biology &Biochemistry, 2005,37:1979-1987.
Wang J H, Liu J S, Yu J B, et al. Effect of fertilizing N and P on soil microbial biomass carbon and nitrogen of black soil corn agroecosystem[J]. Journal of Soil and Water Conversation, 2004,18(1):35-38.
[38]
Zhou J H, Li X C, Jiang Y, et al. Combined effects of bacterial-feeding nematodes and prometryne on the soil microbial activity[J]. Journal of Hazardous Materials, 2011,192(3):1243-1249.
Zhou J, Hu F, Jiao J, et al. Effects of bacterial-feeding nematodes and prometryne-degrading bacteria on the dissipation of prometryne in contaminated soil[J]. Journal of Soils and Sediments, 2012,12:576-585.
