杉木凋落物覆盖对自身幼苗出土和早期生长的影响

doi:10.13287/j.1001-9332.201902.023

摘要/Abstract

摘要： 凋落物可通过物理和化学作用显著影响幼苗出土和早期生长,进而影响天然更新.杉木是中国南方重要的造林树种,但存在着天然更新障碍,其原因可能是林下较厚的凋落物层阻碍了杉木幼苗出土和早期生长.本试验利用覆盖自然和塑料凋落物来研究凋落物对杉木幼苗出土和早期生长的影响,并检验其影响是物理作用还是化学作用.本试验设置2种凋落物类型(自然和塑料凋落物)和4个覆盖厚度(对照,0 g·m^-2;浅层,200 g·m^-2;中层,400 g·m^-2;深层,800 g·m^-2).结果表明: 与对照(0 g·m^-2)相比,浅层(200 g·m^-2)凋落物覆盖对出苗率有促进作用但不显著,深层(800 g·m^-2)凋落物覆盖对出苗率和存活率有显著抑制作用.随着凋落物覆盖厚度的增加,幼苗根长不断减小,而茎长逐渐增加.凋落物浅层覆盖下杉木幼苗的根生物量、叶生物量和总生物量均最大,深层覆盖下最小.幼苗的根冠比随着凋落物覆盖厚度的增加而不断减小.与对照相比,凋落物覆盖下幼苗光合与非光合组织生物量比均有所增加.相同覆盖厚度下,自然和塑料凋落物对杉木幼苗出土和早期生长的影响均无显著差异,表明短期内凋落物覆盖对幼苗出土和早期生长的影响主要是物理作用.随着凋落物覆盖厚度的增加,杉木幼苗出土和早期生长表现为先促进后抑制,且杉木幼苗为了穿过厚厚的凋落物层倾向于把资源分配给地上部分.本研究结果为凋落物是影响杉木幼苗建植和天然更新的一个重要生态因子提供了试验证据.

关键词: 森林更新, 人工林, 物理作用, 塑料凋落物, 生物量分配

Abstract: Litter accumulation can strongly affect seedling emergence and early growth through both physical and chemical mechanisms, and can further influence natural regeneration. Chinese fir (Cunninghamia lanceolata) is one of the most important afforestation tree species. Its natural regeneration is poor, possibly due to the thick leaf accumulation inhibiting seedling emergence and growth. We used natural and plastic litter to study the effects of Chinese fir litter on its own seedling emergence and early growth, as well as to assess whether the effect was physical or chemical. In this experiment, two litter types (natural and plastic litter) and four different litter amounts (control, 0 g·m^-2; low, 200 g·m^-2; medium, 400 g·m^-2; high, 800 g·m^-2) were used. The results showed that compared to the control (0 g·m^-2), low litter amount (200 g·m^-2) exerted a slight positive effect on seedling emergence, whereas high litter amount (800 g·m^-2) significantly reduced the seedling emergence and survival rate in the case of both natural and plastic litter. With increasing litter amount, root length of seedlings decreased and stem length increased. The highest and lowest root mass, leaf mass, and total mass of seedlings were observed for the low and high litter amount, respectively, in the case of both natural and plastic litter. The root:shoot ratio of seedlings decreased with the increasing litter amount for both natural and plastic litter. The photosynthesis:non-photosynthesis biomass ratio of the seedlings was higher under all litter cover treatments, compared to that in the control. Because the effect of the same amounts of the natural and plastic litter on seedling emergence and early growth did not differ, the litter layer’s short-term influence was primarily physical. As the litter cover increased, the initial slight positive effects on seedling emergence and early growth could shift to inhibitory effects. Moreover, to penetrate the thick litter layer, Chinese fir seedlings allocated more resources toward stems and aboveground growth. This study provided evidence for litter amount being a key ecological factor that affects the seedling development and subsequent natural regeneration of Chinese fir.

Key words: plastic litter, physical effect, forest regeneration, plantation, biomass allocation

赵冲蔡一冰黄晓刘青青朱晨曦于姣妲王正宁刘博. 杉木凋落物覆盖对自身幼苗出土和早期生长的影响[J]. 应用生态学报, 2019, 30(2): 481-488.

ZHAO Chong, CAI Yi-bing, HUANG Xiao, LIU Qing-qing, ZHU Chen-xi, YU Jiao-da, WANG Zheng-ning, LIU Bo. Effects of Chinese fir litter cover on its seedling emergence and early growth.[J]. Chinese Journal of Applied Ecology, 2019, 30(2): 481-488.

参考文献

[1] State Forestry Bureau, The People’s Republic of China (中华人民共和国国家林业局). Forestry Resource Statistics for China in 2009-2013 in China Forestry Development Report 2014. Beijing: China Forestry Press, 2014 (in Chinese)
[2] Food and Agriculture Organization of the United Nations. Global Forest Resources Assessment 2015. 2nd Ed. Rome: Food and Agriculture Organization of the United Nations, 2016
[3] Yang YS, Wang LX, Yang ZJ, et al. Large ecosystem service benefits of assisted natural regeneration. Biogeosciences, 2018, 123: 676-687
[4] Chen LC, Wang SL, Wang P, et al. Autoinhibition and soil allelochemical (cyclic dipeptide) levels in replanted Chinese fir (Cunninghamia lanceolata) plantations. Plant and Soil, 2014, 374: 793-801
[5] Yang YS, Guo JF, Chen GS, et al. Litterfall, nutrient return, and leaf-litter decomposition in four plantations compared with a natural forest in subtropical China. Annals of Forest Science, 2004, 61: 465-476
[6] Zhu NH, Yao JY, Zhou GY, et al. Study on natural vegetation regeneration from over maturity plantation of China fir. Journal of Central South University of Forestry and Technology, 2011, 31: 106-110
[7] Bi JB, Blanco JABA, Seely BS, et al. Yield decline in Chinese-fir plantations: A simulation investigation with implications for model complexity. Canadian Journal of Forest Research, 2007, 37: 1615-1630
[8] Zhu J-J (朱教君), Zhang J-X (张金鑫). Thoughts on sustainable management of plantation. Science (科学), 2016, 68(4): 37-40 (in Chinese)
[9] Chen L-C (陈龙池), Wang S-L (汪思龙), Chen C-Y (陈楚莹). Degradation mechanism of Chinese fir plantation. Chinese Journal of Applied Ecology (应用生态学报), 2004, 15(10): 1953-1957 (in Chinese)
[10] Isabelle A, Christian M, Andr B. Can plantations develop understory biological and physical attributes of naturally regenerated forests. Biological Conservation, 2008, 141: 2461-2476
[11] Zhang CL, Li XW, Chen YQ, et al. Effects of Eucalyptus litter and roots on the establishment of native tree species in Eucalyptus plantations in South China. Forest Ecology and Management, 2016, 375: 76-83
[12] Chazdon RL, Guariguata MR. Natural regeneration as a tool for large-scale forest restoration in the tropics: Prospects and challenges. Biotropica, 2016, 48: 716-730
[13] Manson DG, Schmidt S, Bristow M, et al. Species-site matching in mixed species plantations of native trees in tropical Australia. Agroforestry Systems, 2013, 87: 233-250
[14] Liu Z-G (刘足根), Zhu J-J (朱教君), Yuan X-L (袁小兰), et al. Investigation and analysis of the natural regeneration of Larix olgensis in mountain regions of eastern Liaoning Province, China. Scientia Silvae Sinicae (林业科学), 2007, 43(1): 42-49 (in Chinese)
[15] Zhang S-Z (张树梓), Li M (李梅), Zhang S-B (张树彬), et al. Factors affecting natural regeneration of Larix principis-rupprechtii plantations in Saihanba of Hebei, China. Acta Ecologica Sinica (生态学报), 2015, 35(16): 5403-5411 (in Chinese)
[16] Bertacchi MIF, Amazonas NT, Brancalion PHS, et al. Establishment of tree seedlings in the understory of restoration plantations: Natural regeneration and enrichment plantings. Restoration Ecology, 2016, 24: 100-108
[17] Wang J, Ren H, Yang L, et al. Soil seed banks in four 22-year-old plantations in South China: Implications for restoration. Forest Ecology and Management, 2009, 258: 2000-2006
[18] Zhu J-J (朱教君), Liu Z-G (刘足根), Wang H-X (王贺新). Obstacles for natural regeneration of Larix olgensis plantations in montane regions of eastern Liao-ning Province, China. Chinese Journal of Applied Ecology (应用生态学报), 2008, 19(4): 695-703 (in Chinese)
[19] Fan S-H (范少辉), Ma X-Q (马祥庆), Fu R-S (傅瑞树), et al. Comparative study on underground vegetation develop of different generation plantations of Chinese fir. Forest Research (林业科学研究), 2001, 14(1): 8-16 (in Chinese)
[20] Lin K-M (林开敏), Huang B-L (黄宝龙). Studies on β-diversity index of undergrowth plant in Chinese fir plantation. Biodiversity Science (生物多样性), 2001, 9(2): 157-161 (in Chinese)
[21] Lin K-M (林开敏), Yu X-T (俞新妥), Huang B-L (黄宝龙), et al. Dynamical characteristics of undergrowth plant diversity in Chinese fir plantations. Chinese Journal of Applied and Environmental Biology (应用与环境生物学报), 2001, 7(1): 13-19 (in Chinese)
[22] Walck JL, Hidayati SN, Dixon KW, et al. Climate change and plant regeneration from seed. Global Change Biology, 2011, 17: 2145-2161
[23] Yang L-D (羊留冬), Yang Y (杨燕), Wang G-X (王根绪), et al. Effects of forest litter on seed germination and seedling growth. Chinese Journal of Ecology (生态学杂志), 2010, 29(9): 1820-1826 (in Chinese)
[24] Zhu C-X (朱晨曦), Liu Z-G (刘志刚), Yu Y-Y (于洋洋), et al. Composition and seasonal dynamics of seed rain in Chinese fir (Cunninghamia lanceolata) plantation. Chinese Journal of Applied Ecology (应用生态学报), 2018, 29(5): 1515-1522 (in Chinese)
[25] Liu B, Liu QQ, Daryanto S, et al. Responses of Chinese fir and Schima superba seedlings to light gradients: Implications for the restoration of mixed broadleaf-conifer forests from Chinese fir monocultures. Forest Ecology and Management, 2018, 419: 51-57
[26] Shi X-D (石晓东), Gao R-M (高润梅), Han Y-Z (韩有志), et al. Effects of litter on seed germination and seedling growth of two coniferous tree species. Science of Soil and Water Conservation (中国水土保持科学), 2014, 12(4): 112-120 (in Chinese)
[27] Liu F-L (刘芳黎), Zhang Y (张越), Wu F-Q (吴富勤), et al. Effect of autotoxicity and litter allelopathy on seed germination of Rhododendron protistum var. giganteum, a plant species with extremely small populations in China. Acta Botanica Boreali-Occidentalia Sinica (西北植物学报), 2017, 37(6): 1189-1195 (in Chinese)
[28] Liu Q-Q (刘青青), Ma X-Q (马祥庆), Li Y-J (李艳娟), et al. Response of seed germination and seedling growth of Chinese fir to different light intensities. Chinese Journal of Applied Ecology (应用生态学报), 2016, 27(12): 3845-3852 (in Chinese)
[29] Tang C-P (唐翠平), Yuan S-A (袁思安), Li J (李骄), et al. Effects of litter type and thickness on seed germination and seeding growth of Pinus yunnanensis. Guizhou Agricultural Sciences (贵州农业科学), 2014, 42(8): 191-194 (in Chinese)
[30] Kostel-Hughes F, Young TP, Wehr JD. Effects of leaf litter depth on the emergence and seedling growth of deciduous forest tree species in relation to seed size. Journal of the Torrey Botanical Society, 2005, 132: 50-61
[31] Loydi A, Donath TW, Otte A, et al. Negative and positive interactions among plants: Effects of competitors and litter on seedling emergence and growth of forest and grassland species. Plant Biology, 2015, 17: 667-675
[32] Ruprecht E, Jozsa J, Oelvedi TB, et al. Differential effects of several “litter” types on the germination of dry grassland species. Journal of Vegetation Science, 2010, 21: 1069-1081
[33] Donath TW, Eckstein RL. Grass and oak litter exert different effects on seedling emergence of herbaceous perennials from grasslands and woodlands. Journal of Eco-logy, 2008, 96: 272-280
[34] Rotundo JL, Aguiar MR. Litter effects on plant regenera-tion in arid lands: A complex balance between seed retention, seed longevity and soil-seed contact. Journal of Ecology, 2005, 93: 829-838
[35] Ellsworth JW, Harrington RA, Fownes JH. Seedling emergence, growth, and allocation of Oriental bittersweet: Effects of seed input, seed bank, and forest floor litter. Forest Ecology and Management, 2004, 190: 255-264
[36] Olson BE, Wallander RT. Effects of invasive forb litter on seed germination, seedling growth and survival. Basic and Applied Ecology, 2002, 3: 309-317
[37] Hovstad KA, Ohlson M. Physical and chemical effects of litter on plant establishment in semi-natural grasslands. Plant Ecology, 2008, 196: 251-260
[38] Muturi GM, Poorter L, Bala P, et al. Unleached Prosopis litter inhibits germination but leached stimulates seedling growth of dry woodland species. Journal of Arid Environments, 2017, 138: 44-50
[39] Quddus MS, Bellairs SM, Wurm PAS. Acacia holosericea (Fabaceae) litter has allelopathic and physical effects on mission grass (Cenchrus pedicellatus and C. polystachios) (Poaceae) seedling establishment. Australian Journal of Botany, 2014, 62: 189-195
[40] Xia ZC, Kong CH, Chen LC, et al. Allelochemical-mediated soil microbial community in long-term monospecific Chinese fir forest plantations. Applied Soil Ecology, 2015, 96: 52-59
[41] Eckstein RL, Donath TW. Interactions between litter and water availability affect seedling emergence in four familial pairs of floodplain species. Journal of Ecology, 2005, 93: 807-816
[42] Wen Y-G (温远光), Wei S-Z (韦盛章), Qin W-M (秦武明). Analysis on the litter-fall dynamics of Chinese fir plantation and its correlation to climatic factors in north Guangxi. Acta Ecologica Sinica (生态学报), 1990, 10(4): 367-372 (in Chinese)
[43] Gao S-L (郜士垒), He Z-M (何宗明), Huang Z-Q (黄志群), et al. Amount, composition and seasonal dynamics of litterfall in different ages of Cunninghamia lanceolata plantations. Acta Agriculturae Universitatis Jiangxiensis (江西农业大学学报), 2015, 37(4): 638-644 (in Chinese)
[44] Barritt AR, Facelli JM. Effects of Casuarina pauper litter and grove soil on emergence and growth of understorey species in arid lands of south Australia. Journal of Arid Environments, 2001, 49: 569-579
[45] Liu GX, Wan LQ, He F, et al. Effects of litter, seed position, and water availability on establishment of seedlings for two semiarid grass species. Plant Ecology, 2016, 217: 277-287
[46] Harris MR, Lamb D, Erskine PD. An investigation into the possible inhibitory effects of white cypress pine (Callitris glaucophylla) litter on the germination and growth of associated ground cover species. Australian Journal of Botany, 2003, 51: 93-102
[47] Amatangelo KL, Dukes JS, Field CB. Responses of a California annual grassland to litter manipulation. Journal of Vegetation Science, 2008, 19: 605-612
[48] Vázquezyanes C, Orozcosegovia A. Effects of litter from a tropical rainforest on tree seed germination and establishment under controlled conditions. Tree Physiology, 1992, 11: 391-400
[49] Valera-Burgos J, Cruz Diaz-Barradas M, Zunzunegui M. Effects of Pinus pinea litter on seed germination and seedling performance of three Mediterranean shrub species. Plant Growth Regulation, 2012, 66: 285-292
[50] Gaucher C, Gougeon S, Mauffette Y, et al. Seasonal variation in biomass and carbohydrate partitioning of understory sugar maple (Acer saccharum) and yellow birch (Betula alleghaniensis) seedlings. Tree Physiology, 2005, 25: 93-100
[51] Li G-Z (李根柱), Wang H-X (王贺新), Zhu S-Q (朱书全), et al. Barrier effect of litter on natural regeneration in northeast secondary forest. Journal of Liaoning Technical University (Natural Science) (辽宁工程技术大学学报: 自然科学版), 2008, 27(2): 295-298 (in Chinese)
[52] Pan K-W (潘开文), He J (何静), Wu N (吴宁). Effect of forest litter on microenvironment conditions of forestland. Chinese Journal of Applied Ecology (应用生态学报), 2004, 15(1): 153-158 (in Chinese)
[53] Qi SS, Dai ZC, Miao SL, et al. Light limitation and litter of an invasive clonal plant, Wedelia trilobata, inhibit its seedling recruitment. Annals of Botany, 2014, 114: 425-433
[54] Zheng W (郑伟). The Study on Plant Seedling Growth Strategy. PhD Thesis. Changchun: Northeast Normal University, 2011 (in Chinese)
[55] Zhang M (张敏). The Germination, Seedling Survival and Early Growth of the Main Tree Species in Response to Light Regimes in Secondary Forests, Northeast China. PhD Thesis. Shenyang: Institute of Applied Ecology, Chinese Academy of Sciences, 2012 (in Chinese)
[56] Paz H. Root/shoot allocation and root architecture in seedlings: Variation among forest sites, microhabitats, and ecological groups1. Biotropica, 2003, 35: 318-332
[57] Mediavilla S, Escudero A. Differences in biomass allocation patterns between saplings of two co-occurring Mediterranean oaks as reflecting different strategies in the use of light and water. European Journal of Forest Research, 2010, 129: 697-706