岷江上游高山森林凋落叶在冬季河流中的质量损失特征

doi:10.11870/cjlyzyyhj201507014

摘要/Abstract

摘要： 凋落叶在高山森林河流中的分解不仅是生态系统物质循环的重要内容,而且与森林养分流失以及下游水体环境密切相关,并可能受到冬季雪被变化和土壤季节性冻融的影响,但一直缺乏必要的关注。因此,以岷江上游高山森林4种代表性植物康定柳(Salix paraplesia)、高山杜鹃(Rhododendron lapponicum)、方枝柏(Sabina saltuaria)和四川红杉(Larix mastersiana)凋落叶为研究对象,采用凋落叶分解袋法,研究了一个冬季不同冻融时期(冻结初期、冻结期和融化期)的质量损失特征。经过一个冬季(162 d)的分解,康定柳、高山杜鹃、方枝柏和四川红杉凋落叶分别完成了初始干重45.5%、18.9%、26.4%和23.8%的分解;除康定柳凋落叶质量损失在融化期最大外,其余3种凋落叶均表现为冻结初期最大;康定柳、方枝柏和四川红杉凋落叶质量损失与河流水环境的平均温度和正积温均表现出显著或极显著的正相关关系,且与河流流速和硝态氮显著正相关,而与河流pH显著负相关;高山杜鹃凋落叶质量损失除与HCO₃^-含量显著相关外,与河流水温及其它水质特征均无显著相关关系。这些结果表明高山森林河流流速及水环境特征显著影响了凋落叶分解及其相关的物质循环过程,但影响程度受到凋落叶特性的调控。

关键词: 高山森林河流, 凋落叶分解, 河流水特征, 温度

Abstract: Litter decomposition in forested rivers is an important component of material cycle and energy flow in forest ecosystems, and it is a key process of forest nutrient output and information exchange across ecosystems as well. However, little is known on the process of litter decomposition in alpine forest rivers during different freeze-thaw periods in winter. The present study was conducted to investigate litter mass loss during different freeze-thaw periods of winter in an alpine forest river. Using the litterbag method, a field experiment was conducted to investigate foliar litter mass losses of four regional typical plants willow (Salix paraplesia), azalea (Rhododendron lapponicum), cypress (Sabina saltuaria), and larch (Larix mastersiana) in pre-freezing period, freezing period, and thawing period during temperature fluctuation in winter in an alpine forest river in the upper reaches of the Minjiang River. The results suggested that foliar litter of willow, azalea, cypress, and larch lost 45.5%, 18.9%, 26.4% and 23.8% of the initial dry mass after the incubation of a whole winter (162 days), respectively. Compared with the other freeze-thaw periods, foliar litter mass losses were the highest in pre-freezing period except for that of willow, which was the highest in thawing period. Foliar litter mass losses of willow, cypress, and larch were significantly and positively correlated to river average temperature, positive accumulated temperature, flow velocity, and nitrate concentration regardless of sampling periods. The mass losses of these three foliar litter types were significantly and negatively correlated to water pH in river. Except for a significant correlation between azalea foliar litter mass loss and river water HCO₃^- concentration, no significant relation was observed between azalea foliar litter mass loss and water temperature or other water characteristics. These results indicated that water characteristics of the alpine forest river significantly influenced foliar litter decomposition and its related processes of material cycles, but the magnitude of this influence was controlled by foliar litter features. Under a scenario of global warming, the freezing and thawing patterns in alpine forests could be influenced significantly, subsequently having influences on the water physicochemical characteristics and litter decomposition in forested rivers. A warmer temperature in winter may generate a higher river flow velocity, which would promote litter decomposition. Furthermore, warming-induced microbial activities could also accelerate litter decomposition because of constant moisture in aquatic ecosystems. As a result, litter decomposition in alpine forest rivers would be meaningful for nutrient cycling and energy flow relative to that in forest floors under a scenario of global changes.

Key words: alpine forest river, foliar litter decomposition, river water characteristics, temperature

中图分类号:

Q148

岳楷, 杨万勤, 彭艳, 张川, 黄春萍, 吴福忠. 岷江上游高山森林凋落叶在冬季河流中的质量损失特征[J]. 长江流域资源与环境, 2015, 24(07): 1177-1184.

YUE Kai, YANG Wan, PENG Yan, ZHANG Chuan, HUANG Chun, WU Fu-zhong. FOLIAR LITTER MASS LOSS IN WINTER IN AN ALPINE FOREST RIVER IN THE UPPER REACHES OF THE MINJIANG RIVER[J]. RESOURCES AND ENVIRONMENT IN THE YANGTZE BASIN, 2015, 24(07): 1177-1184.

参考文献

[1] GESSNER M O,SWAN C M,DANG C K,et al.Diversity meets decomposition[J].Trends in Ecology & Evolution,2010,25(2):372-380.
[2] BATTIN T J,KAPLAN L A,FINDLAY S,et al.Biophysical controls on organic carbon fluxes in fluvial networks[J].Nature Geosci,2008,1(2):95-100.
[3] TRANVIK L J,DOWNING J A,COTNER J B,et al.Lakes and reservoirs as regulators of carbon cycling and climate[J].Limnology and Oceanography,2009,54(6):2298-2314.
[4] PERAKIS S S,HEDIN L O.Nitrogen loss from unpolluted South American forests mainly via dissolved organic compounds[J].Nature,2002,415(6870):416-419.
[5] BALDY V,GOBERT V,GUEROLD F,et al.Leaf litter breakdown budgets in streams of various trophic status:effects of dissolved inorganic nutrients on microorganisms and invertebrates[J].Freshwater Biology,2007,52(7):1322-1335.
[6] RUEDA-DELGADO G,WANTZEN KM,TOLOSA MB.Leaf-litter decomposition in an Amazonian floodplain stream:effects of seasonal hydrological changes[J].Journal of the North American Benthological Society,2006,25(1):233-249.
[7] 赵勇,苗蕾,孙聪楠,等.树木枯落叶在河流水体中的分解及氮、磷释放动态[J].水土保持学报,2010,24(1):172-175.
[8] SRIDHAR K R,KARAMCHAND K S,SEENA S.Fungal assemblage and leaf litter decomposition in riparian tree holes and in a coastal stream of the south-west India[J].Mycology,2013,4(2):118-124.
[9] TAYLOR B R,CHAUVET E E.Relative influence of shredders and fungi on leaf litter decomposition along a river altitudinal gradient[J].Hydrobiologia,2014,721(1):239-250.
[10] BRUDER A,CHAUVET E,GESSNER M O.Litter diversity,fungal decomposers and litter decomposition under simulated stream intermittency[J].Functional Ecology,2011,25(6):1269-1277.
[11] 刘利,吴福忠,杨万勤,等.季节性冻结初期川西亚高山/高山森林土壤细菌多样性[J].生态学报,2010,30(20):5687-5694.
[12] 夏磊,吴福忠,杨万勤,等.川西亚高山森林凋落叶分解初期土壤动物对红桦凋落叶质量损失的贡献[J].应用生态学报,2012,23(2):301-306.
[13] LEROY C J,MARKS J C.Litter quality,stream characteristics and litter diversity influence decomposition rates and macroinvertebrates[J].Freshwater Biology,2006,51():605-617.
[14] 张新平,王襄平,朱彪,等.我国东北主要森林类型的凋落叶产量及其影响因素[J].植物生态学报,2008,32(5):1031-1040.
[15] ZHANG M,WEI X,SUN P,et al.The effect of forest harvesting and climatic variability on runoff in a large watershed:The case study in the Upper Minjiang River of Yangtze River basin[J].Journal of Hydrology,2012,464:1-11.
[16] 张文广,胡远满,张晶,等.岷江上游地区近30年森林生态系统水源涵养量与价值变化[J].生态学杂志,2007,26(7),1063-1067.
[17] 刘庆,乔永康,吴宁,等.岷江上游山地生态系统退化机理研究核心—关键种群的作用[J].长江流域资源与环境,2005,11(3),274-278.
[18] 邓仁菊,杨万勤,冯瑞芳,等.季节性冻融期间亚高山森林凋落叶的质量损失及元素释放[J].生态学报,2010,30(3),830-835.
[19] TAN B,WU F Z,YANG W Q,et al.Characteristics of soil animal community in the subalpine/alpine forests of western Sichuan during onset of freezing[J].Acta Ecologica Sinica,2010,30(2):93-99.
[20] YANG W Q,WANG K Y,KELLOMAKI S,et al.Annual and monthly variations in litter macronutrients of three subalpine forests in western China[J].Pedosphere,2006,16(6):788-798.
[21] 谭波,吴福忠,杨万勤,等.雪被去除对川西高山森林冬季土壤温度及碳、氮磷动态的影响[J].应用生态学报,2011,22(10):2553-2559.
[22] 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.
[23] 倪祥银,杨万勤,李晗,等.雪被斑块对川西亚高山森林6种凋落叶冬季腐殖化的影响[J].植物生态学报,2014,38(6):540-549.
[24] TOURNA M,FREITAG T E,NICOL G W,et al.Growth,activity and temperature responses of ammonia-oxidizing archaea and bacteria in soil microcosms[J].Environmental Microbiology,2008,10(5):1357-1364.
[25] 何伟,吴福忠,杨万勤,等.雪被斑块对高山森林两种灌木凋落叶质量损失的影响[J].植物生态学报,2013,37(4):306-316.
[26] 刘瑞龙,杨万勤,谭波,等.土壤动物对川西亚高山和高山森林凋落叶第一年不同分解时期N和P元素动态的影响[J].植物生态学报,2013,37(12):1080-1090.
[27] CHON K,SARP S,LEES,et al.Evaluation of a membrane bioreactor and nanofiltration for municipal wastewater reclamation:Trace contaminant control and fouling mitigation[J].Desalination,2011,272(1):128-134.
[28] BAPTIST F,YOCCOZ N G,CHOLER P.Direct and indirect control by snow cover over decomposition in alpine tundra along a snowmelt gradient[J].Plant and Soil,2010,328(1-2):397-410.
[29] ZHU J,HE X,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(6):586-596.
[30] WEBSTER J,MEYER J L.Organic matter budgets for streams:A synthesis[J].Journal of the North American Benthological Society,1997,16(1):141-161.
[31] HIEBER M,GESSNER M O.Contribution of stream detrivores,fungi,and bacteria to leaf breakdown based on biomass estimates[J].Ecology,2002,83(4):1026-1038.
[32] 刘瑞龙,李维民,杨万勤,等.土壤动物对川西高山/亚高山森林凋落叶分解的贡献[J].应用生态学报,2013,24(12),3354-3360.
[33] 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.
[34] GESSNER M O,CHAUVET E,DOBSON M.A perspective on leaf litter breakdown in streams[J].Oikos,1999,85(2):377-384.
[35] PERTERSEN R C,CUMMINS K W.Leaf processing in a woodland stream[J].Freshwater Biology,1974,4(4):343-368.
[36] GRACAS MA,BÄRLOCHER F,GESSNER M O.Methods to study litter decomposition:A practical guide[M].Springer,2005:33-36.
[37] NYKVIS N.Leaching and decomposition of litter I.Experiments on leaf litter of Fraxinus excelsior[J].Oikos,1959,10(2):190-211.
[38] HÄTTENSCHWILER S,TIUNOV V A,SCHEU S.Biodiversity and litter decomposition in terrestrial ecosystems[J].Annual Review of Ecology,Evolution,and Systematics,2005,36:191-218.
[39] LAVELLE P,BLANCHART E,MARTIN A,et al.A hierarchical model for decomposition in terrestrial ecosystems:applications to soils of the humid tropics[J].Biotropica,1993,25(2):130-150.
[40] AERTS R.The freezer defrosting:global warming and litter decomposition rates in cold biomes[J].Journal of Ecology,2006,94(4):713-724.
[41] CORNELISSEN J H,VAN BODEGOM P M,AERTS R,et al.Global negative vegetation feedback to climate warming responses of leaf litter decomposition rates in cold biomes[J].Ecology Letters,2007,10(7):619-627.
[42] MARTÍNEZ A,LARRAÑAGA A,PÉREZ J,et al.Temperature affects leaf litter decomposition in low-order forest streams:field and microcosm approaches[J].FEMS Microbiology Ecology,2014,87(1):257-267.
[43] BOYERO L,PERSON R G,GESSNER M O,et al.A global experiment suggests climate warming will not accelerate litter decomposition in streams but might reduce carbon sequestration[J].Ecology Letters,2011,14(3):289-294.
[44] GRAÇA M,CRESSA C,GESNER T,et al.Food quality,feeding preferences,survival and growth of shredders from temperate and tropical streams[J].Freshwater Biology,2001,46(7):947-957.
[45] CHEEVER B M,WEBSTER J R.Effects of consumers and nitrogen availability on heterotrophic microbial activity during leaf decomposition in headwater streams[J].Freshwater Biology,2014,59(8):1768-1780.
[46] AERTS R.The freezer defrosting:global warming and litter decomposition rates in cold biomes[J].Journal of Ecology,2006,94(4):713-724.

Metrics

Viewed

Full text

Abstract

Cited

Shared

Discussed