氮添加对温带森林细根长期分解的影响

doi:10.7525/j.issn.1673-5102.2017.06.007

摘要/Abstract

摘要： 细根分解是森林生态系统碳循环的重要过程之一，其分解速率受到大气氮沉降增加的潜在影响。利用长期模拟氮沉降样地（2009年至今），采用凋落物分解袋方法，研究了氮添加对温带常见的5个森林树种长期细根分解的影响。结果表明：细根分解呈现先快后慢的趋势，在分解第516天质量损失达30%~50%，之后质量残留率变化较为平缓。总体上，渐近线分解模型可以更准确的反应各处理细根分解速率。氮添加对细根分解具有阶段性影响，分解前期促进细根分解，分解后期抑制分解。在细根分解后期氮添加减缓分解速率，一方面是因为木质素等较难分解的物质所占比例升高所带来的直接影响，另一方面，是因为氮添加改变了微生物活动所带来的间接影响。

关键词: 氮沉降, 温带森林, 细根, 凋落物分解

Abstract: As one of the important processes of carbon(C) cycling in forest ecosystems, fine root litter decomposition is potentially affected by elevated atmospheric nitrogen(N) deposition. Since 2009, a five-year fine root decomposition experiment was conducted in long-term N addition plots using a litter bag method. The decomposition rates of fine roots were higher at the early stage and slower at the later stage of decomposition. Mass loss of fine roots was up to 30% 50% in the 516th day of decomposition, and the variation in the remaining mass was relatively stable in the later stage. In general, the asymptotic decomposition models provided the best prediction for fine root decomposition of the five species. Nitrogen addition had a stage-specific effect on fine root decomposition, which was promotion for the early stage while inhibition for the later. At the later stage, N addition slowed down decomposition rate of fine roots, which was partly due to the direct effect of increasing proportion of recalcitrant compounds, such as lignin, and the indirect effect of alteration in microbial activity was affected by N addition.

Key words: nitrogen deposition, temperate forest, fine root, litter decomposition

中图分类号:

S789.3

李媛媛, 王正文, 孙涛. 氮添加对温带森林细根长期分解的影响[J]. 植物研究, 2017, 37(6): 848-854.

LI Yuan-Yuan, WANG Zheng-Wen, SUN Tao. Response of Fine Root Decomposition to Long-term Nitrogen Addition in the Temperate Forest[J]. Bulletin of Botanical Research, 2017, 37(6): 848-854.

参考文献

1. Liu X J,Zhang Y,Han W X,et al. Enhanced nitrogen deposition over China[J]. Nature,2013,494(7438):459-462.
2. Reay D S,Dentener F,Smith P,et al. Global nitrogen deposition and carbon sinks[J]. Nature Geoscience,2008,1(7):430-437.
3. Nadelhoffer K J,Emmett B A,Gundersen P,et al. Nitrogen deposition makes a minor contribution to carbon sequestration in temperate forests[J]. Nature,1999,398(6723):145-148.
4. Hgberg P. Environmental science:nitrogen impacts on forest carbon[J]. Nature,2007,447(7146):781-782.
5. Sedjo R A. The carbon cycle and global forest ecosystem[J]. Water,Air,& Soil Pollution,1993,70(1-4):295-307.
6. Potter C S. Terrestrial biomass and the effects of deforestation on the global carbon cycle:results from a model of primary production using satellite observations[J]. BioScience,1999,49(10):769-778.
7. Melillo J M,Aber J D,Muratore J F. Nitrogen and lignin control of hardwood leaf litter decomposition dynamics[J]. Ecology,1982,63(3):621-626.
8. 方华,莫江明. 氮沉降对森林凋落物分解的影响[J]. 生态学报,2006,26(9):3127-3136. Fang H,Mo J M. Effects of nitrogen deposition on forest litter decomposition[J]. Acta Ecologica Sa,2006,26(9):3127-3136.
9. Knorr M,Frey S D,Curtis P S. Nitrogen additions and litter decomposition:a meta-analysis[J]. Ecology,2005,86(12):3252-3257.
10. Magill A H,Aber J D. Long-term effects of experimental nitrogen additions on foliar litter decay and humus formation in forest ecosystems[J]. Plant and Soil,1998,203(2):301-311.
11. Fang H,Mo J M,Peng S L,et al. Cumulative effects of nitrogen additions on litter decomposition in three tropical forests in southern China[J]. Plant and Soil,2007,297(1-2):233-242.
12. Hobbie S E. Nitrogen effects on decomposition:a five-year experiment in eight temperate sites[J]. Ecology,2008,89(9):2633-2644.
13. Hobbie S E,Vitousek P M. Nutrient limitation of decomposition in Hawaiian forests[J]. Ecology,2000,81(7):1867-1877.
14. Ludovici K H,Kress L W. Decomposition and nutrient release from fresh and dried pine roots under two fertilizer regimes[J]. Canadian Journal of Forest Research,2006,36(1):105-111.
15. Kaspari M,Garcia M N,Harms K E,et al. Multiple nutrients limit litterfall and decomposition in a tropical forest[J]. Ecology Letters,2008,11(1):35-43.
16. Barantal S,Schimann H,Fromin N,et al. Nutrient and carbon limitation on decomposition in an Amazonian moist forest[J]. Ecosystems,2012,15(7):1039-1052.
17. Hobbie S H,Eddy W C,Buyarski C R,et al. Response of decomposing litter and its microbial community to multiple forms of nitrogen enrichment[J]. Ecological Monographs,2012,82(3):389-405.
18. Berg B. Decomposition of root litter and some factors regulating the process:long-term root litter decomposition in a Scots pine forest[J]. Soil Biology and Biochemistry,1984,16(6):609-617.
19. Berg B,Matzner E. Effect of N deposition on decomposition of plant litter and soil organic matter in forest systems[J]. Environmental Reviews,1997,5(1):1-25.
20. Keeler B L,Hobbie S E,Kellogg L E. Effects of long-term nitrogen addition on microbial enzyme activity in eight forested and grassland sites:implications for litter and soil organic matter decomposition[J]. Ecosystems,2009,12(1):1-15.
21. Berg B,Johansson M B,Ekbohm G,et al. Maximum decomposition limits of forest floor litter types:a synthesis[J]. Canadian Journal of Botany,1996,74(5):659-672.
22. Hobbie S E. Contrasting effects of substrate and fertilizer nitrogen on the early stages of litter decomposition[J]. Ecosystems,2005,8(6):644-656.
23. Berg B,Davey M P,De Marco A,et al. Factors influencing limit values for pine needle litter decomposition:a synthesis for boreal and temperate pine forest systems[J]. Biogeochemistry,2010,100(1-3):57-73.
24. Berg B,Mcclaugherty C. Plant litter:decomposition,humus formation,carbon sequestration[M]. Berlin Heidelberg:Springer,2003.
25. Prescott C E. Litter decomposition:what controls it and how can we alter it to sequester more carbon in forest soils?[J]. Biogeochemistry,2010,101(1-3):133-149.
26. Freschet G T,Cornwell W K,Wardle D A,et al. Linking litter decomposition of above-and below-ground organs to plant-soil feedbacks worldwide[J]. Journal of Ecology,2013,101(4):943-952.
27. Chen H,Harmon M E,Sexton J,et al. Fine-root decomposition and N dynamics in coniferous forests of the Pacific Northwest,U. S. A.[J]. Canadian Journal of Forest Research,2002,32(2):320-331.
28. Clemmensen K E,Bahr A,Ovaskainen O,et al. Roots and associated fungi drive long-term carbon sequestration in boreal forest[J]. Science,2013,339(6127):1615-1618.
29. Bardgett R D,Mommer L,De Vries F T. Going underground:root traits as drivers of ecosystem processes[J]. Trends in Ecology & Evolution,2014,29(12):692-699.
30. Jackson R B,Mooney H A,Schulze E D. A global budget for fine root biomass,surface area,and nutrient contents[J]. Proceedings of the National Academy of Sciences of the United States of America,1997,94(14):7362-7366.
31. 张秀娟,吴楚,梅莉,等. 水曲柳和落叶松人工林根系分解与养分释放[J]. 应用生态学报,2006,17(8):1370-1376. Zhang X J,Wu C,Mei L,et al. Root decomposition and nutrient release of Fraxinus manshurica and Larix gmelinii plantations[J]. Chinese Journal of Applied Ecology,2006,17(8):1370-1376.
32. 宋森,谷加存,全先奎,等. 水曲柳和兴安落叶松人工林细根分解研究[J]. 植物生态学报,2008,32(6):1227-1237. Song S,Gu J C,Quan X K,et al. Fine-root decomposition of Fraxinus mandshurica and Larix gmelinii plantations[J]. Journal of Plant Ecology,2008,32(6):1227-1237.
33. Lin C F,Yang Y S,Guo J F,et al. Fine root decomposition of evergreen broadleaved and coniferous tree species in mid-subtropical China:dynamics of dry mass,nutrient and organic fractions[J]. Plant and Soil,2011,338(1-2):311-327.
34. Lõhmus K,Ivask M. Decomposition and nitrogen dynamics of fine roots of Norway spruce(Picea abies(L.) Karst.) at different sites[J]. Plant and Soil,1995,168-169(1):89-94.
35. Usman S,Singh S P,Rawat Y S,et al. Fine root decomposition and nitrogen mineralisation patterns in Quercus leucotrichophora and Pinus roxburghii forests in central Himalaya[J]. Forest Ecology and Management,2000,131(1-3):191-199.
36. Dornbush M E,Isenhart T M,Raich J W. Quantifying fine root decomposition:an alternative to buried litterbags[J]. Ecology,2002,83(11):2985-2990.
37. Sun T,Mao Z J,Dong L L,et al. Further evidence for slow decomposition of very fine roots using two methods:litterbags and intact cores[J]. Plant and Soil,2013,366(1-2):633-646.
38. Sun T,Dong L L,Wang Z W,et al. Effects of long-term nitrogen deposition on fine root decomposition and its extracellular enzyme activities in temperate forests[J]. Soil Biology and Biochemistry,2016,93:50-59.
39. Eissenstat D M,Wells C E,Yanai R D,et al. Building roots in a changing environment:implications for root longevity[J]. New Phytologist,2000,147(1):33-42.
40. Vogt K A,Grier C C,Vogt D J. Production,turnover,and nutrient dynamics of above-and belowground detritus of world forests[J]. Advances in Ecological Research,1986,15:303-377.
41. Heal O W,Anderson J M,Swift M J. Plant litter quality and decomposition:an historical overview[M].//Cadisch G,Giller K E. Driven by nature:plant litter quality and decomposition. Wallingford,Oxford Shire:CAB International,1997:3-30.
42. Langley J A,Hungate B A. Mycorrhizal controls on belowground litter quality[J]. Ecology,2003,84(9):2302-2312.
43. Hobbie S E,Oleksyn J,Eissenstat D M,et al. Fine root decomposition rates do not mirror those of leaf litter among temperate tree species[J]. Oecologia,2010,162(2):505-513.
44. Xiong Y M,Fan P P,Fu S L,et al. Slow decomposition and limited nitrogen release by lower order roots in eight Chinese temperate and subtropical trees[J]. Plant and Soil,2013,363(1-2):19-31.
45. Zheng J Q,Han S J,Wang Y,et al. Composition and function of microbial communities during the early decomposition stages of foliar litter exposed to elevated CO₂ concentrations[J]. European Journal of Soil Science,2010,61(6):914-925.
46. Carreiro M M,Sinsabaugh R L,Repert D A,et al. Microbial enzyme shifts explain litter decay responses to simulated nitrogen deposition[J]. Ecology,2000,81(9):2359-2365.
47. Hansen K,Vesterdal L,Schmidt I K,et al. Litterfall and nutrient return in five tree species in a common garden experiment[J]. Forest Ecology and Management,2009,257(10):2133-2144.
48. Sinsabaugh R L. Phenol oxidase,peroxidase and organic matter dynamics of soil[J]. Soil Biology and Biochemistry,2010,42(3)391-404.
49. Van Groenigen K J,Six J,Hungate B A,et al. Element interactions limit soil carbon storage[J]. Proceedings of the National Academy of Sciences of the United States of America,2006,103(17):6571-6574.

[1]	宋泊沂, 王明明, 庄伟伟. 3种苔藓植物对模拟大气氮沉降的生理响应[J]. 植物研究, 2024, 44(1): 107-117.
[2]	李赵毅, 郝龙飞, 刘婷岩, 何炎红, 张友, 白淑兰, 杨昕瑜. 接种丛枝菌根真菌对模拟大气氮沉降下灌木铁线莲根系形态及养分承载的影响[J]. 植物研究, 2022, 42(5): 886-895.
[3]	刘婷岩, 郝龙飞, 王续富, 闫海霞, 白淑兰. 氮沉降及菌根真菌对长白落叶松苗木根系构型及根际酶活性的影响[J]. 植物研究, 2021, 41(1): 145-151.
[4]	王续富, 郝龙飞, 郝嘉鑫, 郝文颖, 包会嘎, 白淑兰. 模拟氮沉降和不同外生菌根真菌侵染对樟子松幼苗生长的影响[J]. 植物研究, 2021, 41(1): 138-144.
[5]	赵喆, 金则新. 模拟氮沉降对夏蜡梅幼苗生长及非结构性碳水化合物的影响[J]. 植物研究, 2020, 40(1): 41-49.
[6]	马鹏宇, 张红光, 昝鹏, 顾伟平, 温璐宁, 张子嘉, 翁海龙, 孙涛, 毛子军. 长期氮添加对东北地区兴安落叶松人工林土壤酶的影响[J]. 植物研究, 2019, 39(4): 598-603.
[7]	万雪冰, 王庆贵, 闫国永, 邢亚娟. 天然次生林植物叶片生态化学计量特征及光合特性对长期N沉降的响应[J]. 植物研究, 2019, 39(3): 407-420.
[8]	刘岩, 毛子军. 小兴安岭阔叶红松林不同演替系列森林细根生物量的研究[J]. 植物研究, 2018, 38(4): 583-589.
[9]	张娇, 郝龙飞, 王庆成, 付娇娇, 朱凯月. 模拟氮沉降对落叶松人工林土壤呼吸的影响[J]. 植物研究, 2016, 36(4): 596-604.
[10]	孙红阳1,2；王庆成1*. 张广才岭西坡不同起源林分土壤碳收支机制研究[J]. 植物研究, 2015, 35(4): 590-596.
[11]	梁晶1,2；王庆成1*；许丽娟1；吴文娟1. 抚育对长白山西坡杨桦幼龄林土壤呼吸及碳储量密度的影响[J]. 植物研究, 2015, 35(1): 110-116.
[12]	王凯1；宋立宁2*；吕林有3；张亮1；秦峥媛1. 科尔沁沙地主要造林树种细根生物量垂直分布特征[J]. 植物研究, 2014, 34(6): 824-828.
[13]	刘建才;陈金玲;金光泽*. 模拟氮沉降对典型阔叶红松林土壤有机碳和养分的影响[J]. 植物研究, 2014, 34(1): 121-130.
[14]	侯玲玲;孙涛;毛子军*;吕海亮;赵娟;宋元. 小兴安岭不同林龄天然次生白桦林凋落物分解及养分变化[J]. 植物研究, 2012, 32(4): 492-496.
[15]	王传华;王愿;李俊清*. 光氮耦合作用对化香幼苗碳平衡的影响[J]. 植物研究, 2012, 32(2): 177-182.