Effects of elevated nitrogen deposition on soil microbial biomass carbon in major subtropical forests of southern China

Abstract

The effects of elevated nitrogen deposition on soil microbial biomass carbon (C) and extractable dissolved organic carbon (DOC) in three types of forest of southern China were studied in November, 2004 and June, 2006. Plots were established in a pine forest (PF), a mixed pine and broad-leaved forest (MF) and monsoon evergreen broad-leaved forest (MEBF) in the Dinghushan Nature Reserve. Nitrogen treatments included a control (no N addition), low N (50 kg N/(hm²a)), medium N (100 kg N/(hm²·a)) and high N (150 kg N/(hm²·a)). Microbial biomass C and extractable DOC were determined using a chloroform fumigation-extraction method. Results indicate that microbial biomass C and extractable DOC were higher in June, 2006 than in November, 2004 and higher in the MEBF than in the PF or the MF. The response of soil microbial biomass C and extractable DOC to nitrogen deposition varied depending on the forest type and the level of nitrogen treatment. In the PF or MF forests, no significantly different effects of nitrogen addition were found on soil microbial biomass C and extractable DOC. In the MEBF, however, the soil microbial biomass C generally decreased with increased nitrogen levels and high nitrogen addition significantly reduced soil microbial biomass C. The response of soil extractable DOC to added nitrogen in the MEBF shows the opposite trend to soil microbial biomass C. These results suggest that nitrogen deposition may increase the accumulation of soil organic carbon in the MEBF in the study region.

Key words： nitrogen deposition; microbial biomass; extractable dissolved orgamic carbon (DOC); subtropical forest

Acknowledgements

This study was financially supported by the National Natural Science Foundation of China (Grant No. 30670392), the Knowledge Innovation Program of the Chinese Academy of Sciences (No. KZCX2-YW-432-2) and Postdoctoral Fellowship of Nature Science Foundation of Guangdong Province (No. 06300102).

References

1 Acea M J, Carballas T (1990). Principal components analysis of the soil microbial populations of humid zone of Galicia (Spain). Soil Biol Biochem, 22: 749–759

2 Arnebrandt K, Baath E, Soderstrom B (1990). Changes in microfungal community structure after fertilization of Scots pine forest soils with ammonium nitrate or urea. Soil Biol Biochem, 22: 309–312

3 Baath E, Berg B, Lohm U, Lundgren B, Lundkvist H (1980). Effects of experimental acidification and liming on soil organisms and decomposition in a Scots pine forest. Pedobiologia, 20: 85–100

4 Berg B (1988). Dynamics of nitrogen (¹⁵N) in decomposing Scots pine (Pinus sylvestris) needle litter: Long-term decomposition in a Scots pine forest. Can J Bot, 66: 1539–1546

5 Bowden R D, 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. For Ecol Manag, 196: 43–56

6 Boxman A W, Blanck K, Brandrud T E (1998). Vegetation and soil biota response to experimentally-changed nitrogen inputs in coniferous forest ecosystems of the NITREX project. For Ecol Manag, 101: 65–79

7 Compton J E, Watruda L S, Porteous L, DeGrood S (2004). Response of soil microbial biomass and community composition to chronic nitrogen additions at Harvard forest. For Ecol Manag, 196:143–158

8 Deforest J L, Zak D R, Pregitzer K S (2004). Atmospheric nitrate deposition and the microbial degradation of cellobiose and vanillin in a northern hardwood forest. Soil Biol Biochem, 36: 965–971

9 Diaz-Ravina M, Acea M J, Carballas T (1995). Seasonal changes in microbial biomass and nutrient flush in forest soils. Biol Fert Soils, 19: 220–226

10 Fang Y T, Zhu W X, Mo J M, Zhou G Y, Gundersen P (2006). Dynamics of soil inorganic nitrogen and their responses to nitrogen additions in three subtropical forests, South China. J Entomol Sci, 18(4): 756–763

11 Fenn M A, Poth M A, Aber J D, Baron J S, Bormann B T, Johnson D W, Lemly A D, McNulty S G, Ryan D F, Stottlemyer R (1998). Nitrogen excess in North American ecosystems: Predisposing factors, ecosystem responses, and management strategies. Ecol Appl, 8: 706–733

12 Foster N W, Nicolson J A, Haslett P W (1989). Temporal variation in nitrate and nutrient actions in drainage water from a deciduous forest. J Environ Qual, 18: 238–244

13 Frey S D, Knorr M, Parrent J L, Simpson R T (2004). Chronic nitrogen enrichment affects the structure and function of the soil microbial community in temperate hardwood and pine forests. For Ecol Manag, 196: 159–171

14 Fu S L, Yi W M, Ding M M (1995). Mineralization of soil microbial C, N, P and K in different vegetation types at Dinghushan Biosphere Reserve. Acta Phytoecol Sin, 19(3): 217–224 (in Chinese)

15 Guggenberger G, Zech W (1994). Dissolved organic carbon in forest floor leachates: simple degradation products or humic substances? Sci Total Environ, 152: 37–47

16 Haynes B E, Gower S T (1995). Belowground carbon allocation in unfertilized and fertilized red pine plantations in northern Wisconsin. Tree Physiol, 15: 317–325

17 Huang Z F, Fan Z G (1982). The climate of Dinghushan. Trop Subtrop Ecosyst, 1: 11–23 (in Chinese)

18 Huang Z L, Ding M M, Zhang Z P, Yi W M (1994). The hydrological processes and nitrogen dynamics in a monsoon evergreen broad-leaved forest of Dinghushan. Acta Phytoecol Sin, 18:194–199 (in Chinese)

19 Jenkinson D S (1987). Determination of microbial biomass carbon and nitrogen in soil. In: Wilson J R, ed. Advances in N Cycling in Agricultural Ecosystem. London: CBAT National, 368–386

20 Joergensen R G, Anderson T H, Wolters V (1995). Carbon and nitrogen relationships in the microbial biomass of soils in beech (Fagus sylvatica L.) forests. Biol Fert Soils, 19: 141–147

21 Katzensteiner K, Glatzel G, Kazda M (1992). Nitrogen induced nutritional imbalances–a contributing factor to Norway spruce decline in the Bohemian Forest (Austria). For Ecol Manag, 51: 29–42

22 Li B F (1997). Experimental studies on the effect of aluminum in the soil on the root system of Pinus taeda. J Fujian For Sci Tech, 24(1): 66–68 (in Chinese)

23 Lilleskov E A, Fahey T J, Horton T R, Lovett G M (2002). Below ground ectomycorrhizal fungal community change over a nitrogen deposition gradient in Alaska. Ecology, 83: 104–115

24 Luo H, Liu P, Xu G D (2004). Effects of aluminum stress on the microflora of red soil. Ecol Environ, 13(1): 11–13 (in Chinese)

25 Magill A H, Aber J D (1998). Long term effects of experimental nitrogen addition on foliar litter decay and humus formation in forest ecosystems. Plant Soil, 203: 301–311

26 Magill A H, Aber J D, Hendricks J J, Bowden R D, Mëlillo J M, Paul A, Steudler A (1997). Biogeochemical response of forest ecosystems to simulated chronic nitrogen deposition. Ecol Appl, 7: 402–415

27 Matlou M C, Haynes R J (2006). Soluble organic matter and microbial biomass C and N in soils under pasture and arable management and the leaching of organic C, N and nitrate in a lysimeter study. Appl Soil Ecol, 34: 160–167

28 Matson P A, McDowell W H, Townsend A R, Vitousek P M (1999). The globalization of N deposition: ecosystem consequences in tropical environments. Biogeochemistry, 46: 67–83

29 Mo J M, Xue J H, Fang Y T (2004). Litter decomposition and its responses to simulated N deposition for the major plants of Dinghushan forests in subtropical China. Acta Ecol Sin, 24(7): 1413–1420 (in Chinese)

30 Mo J M, Brown S, Peng S L, Kong G H (2003). Nitrogen availability in disturbed, rehabilitated and mature forests of tropical China. For Ecol Manag, 175: 573–583

31 Mo J M, Brown S, Xue J H, Fang Y T, Li Z A (2006). Response of litter decomposition to simulated nitrogen deposition in disturbed, rehabilitated and mature forests in subtropical China. Plant Soil, 285: 135–151

32 Paul J W, Beauchamp E G (1996). Soil microbial biomass C, N mineralization and N uptake by corn in dairy cattle slurry and urea amended soils. Can J Soil Sci, 76: 469–472

33 Phillips R P, Yanai R D (2004). The effects of AlCl₃ additions on rhizosphere soil and fine root chemistry of sugar maple (Acer saccharum). Water Air Soil Poll, 159: 339–356

34 Piao H C, Hong Y T, Yuan Z Y (2000). Seasonal changes of microbial biomass carbon related to climatic factors in soils from karst areas of southwest China. Biol Fert Soils, 30: 294–297

35 Ren R, Mi F J, Bai N B. A (2000). Chemometrics analysis on the data of precipitation chemistry of China. J Beijing Polytech Univ, 26(2): 90–95 (in Chinese)

36 Sha L Q, Zheng Z, Feng Z L, Liu Y H, Liu W J, Meng Y (2002). Biogeochemical cycling of nitrogen at a tropical seasonal rain forest in Xishuangbanna, SW, China. Acta Phytoecol Sin, 26(6): 689–694 (in Chinese)

37 Smolander A, Kurka A, Kitunen V (1994). Microbiomass C and N and respiratory activity in soil of repeatedly limed and N and P fertilized Norway spruce stands. Soil Biol Biochem, 26: 957–962

38 van Breemen N,van Dijk H F G (1988). Ecosystem effects of atmospheric deposition of nitrogen in the Netherlands. Environ Pollut, 54: 249–274

39 Vance E D, Brookes S A, Jenkinson D S (1987). An extraction method for measuring soil microbial biomass C. Soil Biol Biochem, 19: 703–707

40 Vitousek P M, Aber J D, Howarth R W, Likens G E, Matson P A, Schindler D W, Schlesinger W H, Tilman G D (1997). Human alteration of the global nitrogen cycle: Sources and consequences. Ecol Appl, 7(3): 737–750

41 Wallenda T, Kottke (1998). Nitrogen deposition and ectomycorrhizas. New Phytol, 139:169–187

42 Wallenstein M D (2003). Effects of nitrogen fertilization on soil microbial communities, Geophysical Research Abstracts. Eur Geophys Soc, 5: 13087

43 Wallenstein M D, McNulty S, Fernandez I J, Boggs J, Schlesinger W H (2006). Nitrogen fertilization decreases forest soil fungal and bacterial biomass in three long-term experiments. For Ecol Manag, 222: 459–468

44 Wang X F, Li S Y, Bai K J, Kuang T Y (1998). Influence of doubled CO₂ on plant growth and soil microbial biomass C and N. Acta Bot Sin, 40(12): 1169–1172 (in Chinese)

45 Xue J H, Mo J M, Li J, Li D J (2007). The short-term response of soil microorganism number to simulated nitrogen deposition. Guangxi Bot, 27(2): 174–179 (in Chinese)

46 Yao W H, Yu Z Y (1995). The nutrient content of throughfall inside the artificial forests on downland. Acta Ecol Sin, 15: 124–131 (in Chinese)

47 Yi Z G, Yi W M, Zhou L X, Wang X M (2005). Soil microbial biomass of the main forests in Dinghushan Biosphere Reserve. Ecol Environ, 14(5): 727–729 (in Chinese)

48 Zhou G Y, Yan J H (2001). The influence of region atmospheric precipitation characteristics and its element inputs on the existence and development of Dinghushan forest ecosystems. Acta Ecol Sin, 21: 2002–2012 (in Chinese)