桂林毛村岩溶区不同土地利用方式土壤有机碳矿化及土壤碳结构比较

杨慧; 张连凯; 曹建华; 于奭

doi:10.3969/j.issn.1001-4810.2011.04.010

桂林毛村岩溶区不同土地利用方式土壤有机碳矿化及土壤碳结构比较

doi: 10.3969/j.issn.1001-4810.2011.04.010

中国地质科学院岩溶地质研究所/国土资源部、广西岩溶动力学重点实验室

基金项目: 国家自然科学基金(40872213)、地调项目(水[2010]矿评03-07-02)、广西科技厅“岩溶动力学重点实验室(11-031-06)、国家地质实验测试中心基本科研业务费专项经费(No.201011CSJ09)

计量
- 文章访问数: 2486
- HTML浏览量: 507
- PDF下载量: 1850
- 被引次数: 0
出版历程
- 收稿日期: 2011-10-14
- 发布日期: 2011-12-25

Comparison of mineralization and chemical structure of the soil organic carbon under different land uses in Maocun karst area, Guilin

Institute of Karst Geology, CAGS / Karst Dynamics Laboratory, MLR & GZAR

摘要

摘要: 应用土壤培养法,比较分析了桂林毛村岩溶区不同土地利用方式(农田、灌丛和林地)土壤在25℃、黑暗条件下培养90d有机碳矿化速率的差异(以90d累计释放的CO2-C计)。农田土壤矿化释放的CO2-C含量分别比灌丛和林地少62.9%和56.6%。利用6mol/L的HCl酸解法得到惰性碳含量,并利用三库一级动力学方程在SAS8.2软件中通过非线性拟合得到三种土地利用方式的活性碳库、缓效性碳库的大小及其分解速率,计算得出各库驻留时间。结果表明各土地利用方式均为活性碳库含量最少,占总有机碳的比例在1.82%~2.71%之间,平均驻留时间在8.4~16.3d之间;缓效性碳库次之,占总有机碳的比例在33.91%~45.47%之间,平均驻留时间为4.8~7.7a之间;惰性碳库所占比例最大,在51.82%~64.01%之间,平均驻留时间为假定的1000a。通过固态13C交叉极化魔角自旋核磁共振(13CCPMASNMR)方法对土壤碳结构进行分析,结果表明:与灌丛和林地相比,受人类活动干扰较多的农田烷基C和芳香C的比例增加,烷氧C和羰基C的比例降低;烷基C/烷氧C和疏水C/亲水C的大小顺序均为农田>林地>灌丛,而脂族C/芳香C的大小顺序则相反,即灌丛>林地>农田。这说明农田土壤有机碳分解程度较高,难分解程度增加,难分解有机碳比例增加。
- 岩溶区 /
- 土壤有机碳 /
- 矿化 /
- 土壤碳结构
Abstract: Testing the CO2-C content released from the soil is the way to study the mineralization rate of the soil organic carbon(SOC). Thus, we collected soil samples from farmland, shrub land and forest in Maocun karst area in Guilin, and incubated in the laboratory in the dark at 25℃ with a constant moisture of 75% during 90 days, then analyzed the amount of cumulative CO2-C released over 90 days to study the difference of SOC mineralization rate under different land use types. It was found that the mean concentration of CO2-C (gCO2-C?kg-1soil?90d-1) from SOC mineralization in farmland was 62.9% and 56.6% lower than those in the shrub land and forestland respectively. Meanwhile, the chemical structure of soil organic carbon pool in above-mention land use types is studied. The SOC pool are divided into three pools, that is passive-, slow-, and ative- organic carbon pool. Firstly, using acid hydrolysis (6M HCl) to fractionate passive organic carbon, then separate active and slow carbon pools and calculates their decomposition rate and residence time with the “three-pool first-order model”. The results showed that active carbon pool (Ca) comprised 1.82% to 2.71% of the SOC, with an average mean residence time (MRT) of 8.4 to 16.3 days, while slow carbon pool comprised 33.91% to 45.47% of the SOC, with an MRT of 4.8 to 7.7 years, and passive carbon pool comprised 51.82% to 64.01%, with an assumed MRT of 1000 years. Finally，the chemical structure of the organic carbon was analyzed by solid state 13C via polarization magic angle spinning nuclear magnetic resonance (13C CPMAS NMR) . The results showed that, in comparison to the shrub and forest lands, the proportion of alkyl C and aromatic C in farmland which suffered more human disturbance increased, while the proportion of O-alkyl C and carbonyl C decreased. Both the order of alkyl C/ O-alkyl C and hydrophobic C / hydrophilic C are farmland＞forestland＞shrub land, while the order of aliphatic C/aromatic C was the opposite. This shows that SOC in farmland has higher degree decomposition and is more difficult to decompose than the above other land types.
- karst area /
- soil organic carbon /
- mineralization /
- chemical structure of soil organic carbon

HTML

参考文献(33)

[1]	曹建华,潘根兴,袁道先.不同植物凋落物对土壤有机碳淋失的影响及岩溶效应［J］第四纪研究,2000,20(4):359-366.
[2]	吴建国,张小全,徐德应.六盘山林区几种土地利用方式对土壤有机碳矿化影响的比较［J］植物生态学报,2004,28(4):530-538.
[3]	Coleman K, Jenkinson D S, Crocker G J, et al. Simulating trends in soil organic carbon in long-term experiments using RothC-26.3［J］. Geoderma,1997,81(1/2):29-44.
[4]	Murty D, Kirschbaum M U F, Mcmurtrie R E, et al. Does conversion of forest to agricultural land change soil carbon and nitrogen? A review of the literature［J］. Global Change Biology,2002,8(2):105-123.
[5]	Guo L B, Gifford R M. Soil carbon stocks and land use change: a meta analysis［J］. Global Change Biology,2002,8(4):345-360.
[6]	Soussana J F, Loiseau P, Vuichard N, et al. Carbon cycling and sequestration opportunities in temperate grasslands［J］. Soil Use and Management,2004,20(2):219-230.
[7]	Ritter E. Carbon, nitrogen and phosphorus in volcanic soils following afforestation with native birch(Betula pubescens) and introduced larch (Larix sibirica) in Iceland［J］. Plant and Soil,2007,295(1/2):239-251.
[8]	Davidson E A, Galloway L F, Strand M K. Assessing available carbon: comparison of techniques across selected forest soils［J］. Communications in Soil Science and Plant Analysis,1987,18:45-64.
[9]	H P Collins, Paul E A, Paustian K, et al. Characterization of soil organic carbon relative to its stability and turnover［C］//Paul E A, Paustian K, Elliot E T, et al. Soil organic matter in temperate agroecosystems, long-term experiments in North America. Boca Raton, Florida:CRC Press,Inc.1997:51-72.
[10]	Robertson G P, Wedin D, Groffman P M, et al. Soil carbon and nitrogen availability. In: Robertson G P, Bledsoe C S, Coleman D C, et al. Standard soil methods for long-term ecological research［M］. New York: Oxford University Press,Inc. 1999:258-271.
[11]	卓苏能,文启孝.核磁共振技术在土壤有机质研究中应用的新进展［J］.土壤学进展,1994,22(6):26-34.
[12]	王世杰,季宏军,欧阳自远,等.碳酸盐岩风化成土的初步研究［J］.中国科学(D辑),1999,29(5):441-449.
[13]	曹建华,袁道先,潘根兴.岩溶生态系统中的土壤［J］.地球科学进展,2003,18(1):203-209.
[14]	Falkowski P, Scholes R J, Boyle E, et al. The Global Carbon Cycle: A Test of Our Knowledge of Earth as a System［J］. Science,2000,290(5490): 291-296.
[15]	潘根兴,曹建华.表层带岩溶作用:以土壤为媒介的地球表层生态系统过程——以桂林峰丛洼地岩溶系统为例［J］.中国岩溶,1999,18(4):287-296.
[16]	曹建华,周莉,杨慧,等.桂林毛村岩溶区与碎屑岩区林下土壤碳迁移对比及岩溶碳汇效应研究［J］.第四纪研究,2011,31(3):431-437.
[17]	鲍士旦.土壤农化分析［M］.北京:中国农业出版社,2000:30-37,80-87.
[18]	Leavitt S W, Follett R F, Paul E A. Estimation of the slow and fast cycling soil organic carbon pools from 6N HCl hydrolysis［J］. Radiocarbon,1996,38:230-231.
[19]	邵月红,潘剑君,孙波.不同森林植被下土壤有机碳的分解特征及碳库研究［J］.水土保持学报,2005,19(3):24-28.
[20]	Conte P, Piccolo A, Van lagen B, et al. Quantitative differences in evaluating soil humic substances by liquid-and solid-state 13C-NMR spectroscopy［J］. Geoderma,1997,80:339-352.
[21]	Collins H P, Elliott E T. Soil organic matter dynamics in corn-based agroecosystems of the central USA：Results from 13C natural abundance［J］. Soil Science Society of American Journal,1999,63:584-591.
[22]	邵月红,潘剑君,孙波.农田土壤有机碳库大小及周转［J］.生态学杂志,2006,25(1):19-23.
[23]	史学军,陈锦盈,潘剑君.几种不同类型土壤有机碳库容大小及周转研究［J］.水土保持学报,2008,22(6):123-127.
[24]	Haynes R J. Labile organic matter fractions and aggregate stability under short-term, grass-based leys［J］. Soil Biology & Biochemistry,1999,31:1821-1830.
[25]	Motavalli P P, Discekici H, Kuhn J. The impact of land clearing and agricultural practices on soil organic C fractions and CO2 efflux in the Northern Guam aquifer［J］. Agriculture Ecosystems and Environment,2000,79:17-27.
[26]	吴建国,张小全,王彦辉,等.土地利用变化对土壤物理组分中有机碳分配的影响［J］.林业科学,2002,38(4):19-29.
[27]	史学军,潘剑君,陈锦盈,等.不同类型凋落物对土壤有机碳矿化的影响［J］.环境科学,2009,30(6):1832-1837.
[28]	梁重山,党志.核磁共振波谱法在腐殖质研究中的应用［J］.农业环境保护,2001,20(4):277-279.
[29]	张晋京,窦森,朱平,等.长期施用有机肥对黑土胡敏素结构特征的影响——固态13C核磁共振研究［J］.中国农业科学,2009,42(6):2223-2228.
[30]	Dou S, Zhang J J, Li K. Effects of organic matter applications on 13C-NMR spectra of humic acids of soil［J］. European Journal of Soil Science,2008, 59: 532-539.
[31]	Ussiri D A N, Johnson C.E. Characterization of organic matter in a northern hardwood forest soil by 13C NMR spectroscopy and chemical methods［J］. Geoderma, 2003, 111:123-149.
[32]	Piccolo A, Mbagwu J S C. Role of hydrophobic components of soil organic matter in soil aggregate stability［J］. Soil Science Society of America Journal, 1999, 63:1801-1810.
[33]	Spaccini R, Mbagwu J S C, Conte P, et al. Changes of humic substances characteristics from forested to cultivated soils in Ethiopia［J］. Geoderma, 2006, 132:9-19.