长江上游高山森林林窗对凋落物分解过程中可溶性碳的影响

doi:10.11870/cjlyzyyhj201505023

摘要/Abstract

摘要： 采用凋落物分解袋法, 以川西高山森林典型乔木(四川红杉Larix mastersiana、岷江冷杉Abies faxoniana、红桦Betula albo-sinensis和方枝柏Sabina saltuaria)和灌木(高山杜鹃Rhododendron lapponicum和康定柳Salix paraplesia)凋落物为研究对象, 研究了林窗中心到郁闭林下不同生境(林窗中心、林冠林窗、扩展林窗和郁闭林下)中凋落物第一年分解不同关键时期(雪被形成期、雪被覆盖期、雪被融化期和生长季节)可溶性碳的动态特征。结果表明:6种凋落物可溶性碳和可溶性有机碳在冬季含量增加而在生长季节含量降低, 而可溶性无机碳含量在全年呈降低趋势;雪被形成期, 6种凋落物可溶性碳和可溶性有机碳在郁闭林下达到最大值, 而雪被覆盖期在林窗中心和林冠林窗达到最大值, 生长季节6种凋落物可溶性碳含量均低于初始含量。这表明全球气候变暖情景下, 冬季林内雪被覆盖时间和厚度降低且生长季节延长将减少凋落物可溶性碳含量, 且变化程度受到凋落物质量控制。

关键词: 林窗, 高山森林, 可溶性碳, 凋落物分解, 雪被覆盖

Abstract: Soluble carbon during foliar litter decomposition in alpine forests plays an important role in carbon cycling in ecosystems, which is also closely related to the material and energy flow in downstream ecosystems. However, forest gaps could regulate soluble carbon dynamics during litter decomposition by changing the frequency of soil freeze-thaw cycles in winter and hydrothermal environment in growing seasons, but little information has been available. Therefore, a field litterbag experiment was conduct in an alpine forest in western Sichuan Province, China from 15 November 2012 to 31 October 2013. Foliar litter of typical arbor species (birch: Betula albo-sinensis, cypress: Sabina saltuaria, larch: Larix mastersiana and fir: Abies faxoniana) and shrub species (willow: Salix paraplesia, azalea: Rhododendron lapponicum) were selected. Samples of air-dried foliar litter were filled in nylon litterbags and placed on the forest floor with 2 cm spacing between litterbags from the gap center, canopy gap edge, extended gap edge to closed canopy in the alpine forest. The litterbags were sampled at snow formation stage, snow cover stage, snow melt stage and growing season in the first year of decomposition. The results indicated that the content of soluble carbon and soluble organic carbon from the foliar litter of the six species showed a similar dynamical tendency at the first year of litter decomposition. Both contents of soluble carbon and soluble organic carbon increased in winter, and decreased in growing season, though the content of soluble inorganic carbon decreased in the first year of litter decomposition. The maximum contents of soluble carbon and soluble organic carbon in closed canopy were observed at snow formation stage regardless of litter species, but those in gap center and extended gap edge were observed at snow cover stage. In contrast, the contents of soluble carbon, soluble organic carbon and soluble inorganic carbon decreased significantly in growing season, even less than the initial contents. Multivariate analysis displayed that the contents of soluble carbon and soluble inorganic carbon were significantly affected by forest gap in the first year of litter decomposition, but the content of soluble organic carbon only affected by forest gap in the winter. Moreover, the contents of soluble carbon and soluble organic carbon were influenced particularly by litter quality in the winter. These results suggested that the ongoing winter warming would decrease the content of soluble carbon during foliar litter decomposition by decreasing the cover-time and thickness of snow in the winter, although the decrease degree could be controlled by litter quality.

Key words: forest gap, alpine forest, soluble carbon, litter decomposition, snow cover

中图分类号:

S718.53

徐李亚, 杨万勤, 李晗, 倪祥银, 何洁, 吴福忠. 长江上游高山森林林窗对凋落物分解过程中可溶性碳的影响[J]. 长江流域资源与环境, 2015, 24(05): 882-891.

XU Li-ya, YANG Wan-qin, LI Han, NI Xiang-yin, HE Jie, WU Fu-zhong. EFFECTS OF FOREST GAPS ON SOLUBLE CARBON DURING FOLIAR LITTER DECOMPOSITION IN AN ALPINE FOREST IN THE UPPER YANGTZE RIVER[J]. RESOURCES AND ENVIRONMENT IN THE YANGTZE BASIN, 2015, 24(05): 882-891.

参考文献

[1] BERG B, MCCLAUGHERTY C.Plant litter-decomposition, humus formation, carbon sequestration[M].Berlin, Germany:Springer-Verlag, 2008.
[2] 王春阳, 周建斌, 夏志敏, 等.黄土高原区不同植物凋落物可溶性有机碳含量及其降解[J].应用生态学报, 2010, 21(12):3001-3006.
[3] STANLEY E H, POWEERS S M, LOTTIG N R, et al.Contemporary changes in dissolved organic carbon(DOC) in human dominated rivers:Is there a role for DOC management[J]? Freshwater Biology, 2012, 57:26-42.
[4] ADAIR E C, PARTON W J, DEL GROSSO S J, et al.Simple three-pool model accurately describes patterns of long-term litter decomposition in diverse climates[J].Global Change Biology, 2008, 14:2636-2660.
[5] PRESTON C M, NAULT J R, TROFYMOW J A, et al.Chemical changes during 6 years of decomposition of 11 litters in some Canadian forest sites.Part1.Elemental composition, tannins, phenolics, and proximate fractions[J].Ecosystems, 2009, 12:1053-1077.
[6] 武启骞, 吴福忠, 杨万勤, 等.季节性雪被对高山森林凋落物分解的影响[J].植物生态学报, 2013, 37(4):296-305.
[7] BOKHORST S, METCALFE D B, WARDLE D A.Reduction in snow depth negatively affects decomposers but impact on decomposition rates is substrate dependent[J].Soil Biology and Biochemistry, 2013, 62:157-164.
[8] 张艳华, 聂绍荃, 王志西, 等.林隙对草本植物的影响[J].植物研究, 1999, 19(1):94-99.
[9] 吴宁.贡嘎山东坡亚高山针叶林的林窗动态研究[J].植物生态学报, 1999, 23(3):228-237.
[10] WU F Z.YANG W Q, ZHANG J, et al.Litter decomposition in two subalpine forests during the freeze-thaw season[J].Acta Oecologica, 2010, 36(1):135-140.
[11] KEANE R E.Biophysical controls on surface fuellitter fall and decomposition in the northern Rocky Mountains, USA[J].Canadian Journal of Forest Research, 2008, 38:1431-1445.
[12] ZHU J X, HE X H, WU F Z, et al.Decomposition of Abies faxoniana litter varies with freeze-thaw stages and altitudes in subalpine/alpine forests of southwest China[J].Scandinavian Journal of Forest Research, 2012, 27:586-596.
[13] USELMAN S M, QUALLS R G, LILIENFEIN J.Quality of soluble organic C, N, and P produced by different types and species of litter:Root litter versus leaf litter[J].Soil Biology and Biochemistry, 2012, 54:57-67.
[14] 国家环境保护局.水质总有机碳的测定(GB 13193-91) [S].北京:中国标准出版社, 1992.
[15] DON A, KALBITZ K.Amounts and degradability of dissolved organic carbon from foliar litter at different decomposition stages[J].Soil Biology and Biochemistry, 2005, 37:2171-2179.
[16] MAGILL A H, ABER J D.Dissolved organic carbon and nitrogen relationships in forest litter as aected by nitrogen deposition[J].Soil Biology and Biochemistry, 2000, 32:603-613.
[17] BROOKS P D, GROGAN P, TEMPLER P H, et al.Carbon and Nitrogen Cycling in Snow-Covered Environments[J].Geography Compass, 2011, 5(9):682-699.
[18] WANG F L, BETTANY G R.Influence of freeze-thaw and flooding on the loss of soluble organic carbon and carbon dioxide from soil[J].Journal of Envirnmental Quality, 1993, 22(4):709 -714.
[19] 郝瑞军, 李忠佩, 车于萍, 等.苏南水稻土有机碳矿化特征及其与活性有机碳组分的关系[J].长江流域资源与环境, 2010, 19(9):1069-1074.
[20] 于小舟, 袁凤辉, 王志安, 等.积雪对长白山阔叶红松林土壤温度的影响[J].应用生态学报, 2010, 21(12):3015-3020.
[21] CLINE D W.Snow surface energy exchanges and snow melt at a continental, midlatitude alpine site[J].Water Resources Research, 1997, 33:689-701.
[22] 代静玉, 秦淑平, 周江敏, 等.水杉凋落物分解过程中溶解性有机质的分组组成变化[J].生态环境, 2004, 13(2):207-210.
[23] FRÖBERG M, KLEJA D B, HAGEDORN F.The contribution of fresh litter to dissolved organic carbon leached from a coniferous forest floor[J].European Journal of Soil Science, 2007, 58:108-114.
[24] 梁晓东, 叶万辉, 蚁伟民, 等.林窗与生物多样性维持[J].生态学杂志, 2001, 20(5):64-68.
[25] 范跃新, 杨玉盛, 杨智杰, 等.中亚热带常绿阔叶林不同演替阶段土壤活性有机碳含量及季节动态[J].生态学报, 2013, 33(18):2-9.
[26] HONGVE D, VANHEES P A W, LUNDSTRÖM U S.Dissolved components in precipitation water percolated through forest litter[J].European Journal of Soil Science, 2000, 51:667-677.
[27] YANAI R D, ARTHUR M A, SICCAMA T G, et al.Challenges of measuring forest floor organic matter dynamics:repeated measures from a chronosequence[J].For Ecol Manage, 2000, 138:273-283.
[28] KUZYAKOV Y, SCHNECKENBERGER K.Review of estimation of plant rhizodeposition and their contribution to soil organic matter formation[J].Archives of Agronomy and Soil Science, 2004, 50(1):115-132.
[29] 刘丽娟, 王玉刚, 李小玉, 等.干旱区绿洲土壤可溶性无机碳的空间分布特征[J].生态学杂志, 2013, 32(10):2539-2544.

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