Effects of tree sapling diversity and nutrient addition on herb-layer invasibility in communities of subtropical species

Sabine Both, Teng Fang, Martin Baruffol, Bernhard Schmid, Helge Bruelheide, Alexandra Erfmeier

.
Gutianshan National Nature Reserve, Quzhou, China.
Institute of Biology/Geobotany and Botanical Garden, Martin Luther University Halle-Wittenberg, Halle, Germany.
Institute of Evolutionary Biology and Environmental Studies, University of Zürich, Zürich, Switzerland.

DOI: 10.4236/oje.2012.21001                

Abstract

Exotic species are assumed to alter ecosystem functioning. However, little is known of the relationships within vertically structured plant communities such as forests, where tree saplings interact with herbaceous species, especially in the early phases of succession. This relationship was tested in a common garden experiment which assessed the impacts on tree saplings and herbaceous species following nutrient addition and the introduction of exotic herb species. The experiment was established in South- East China using four broad-leaved tree species (Elaeocarpus decipiens, Schima superba, Castanea henryi and Quercus serrata) to study the relationships between tree sapling diversity, herb-layer productivity and invasibility. Tree saplings were planted in monoculture and in mixtures of two and four species. A full factorial design was applied, within which species composition was crossed with nutrient and exotic seed-addition treatments. The seed-addition treatment included mixtures of seeds from eight exotic herb species, and herb community attributes were assessed after a four month growing season. Results indicate that certain tree species negatively affect native as well as exotic herbs; however, the high productivity of native herbs had a stronger negative impact on exotic species than tree saplings. Nutrient addition increased the productivity of exotic herbs but had no effect on native herbs. Remarkably, exotic species introduction had a negative feedback effect on the growth of tree saplings, which highlights the potential of exotic herbs to diminish tree recruitment. Although tree saplings reduced invasive effects on the herb-layer during the earliest phase of forest succession, nutrient addition had a more profound and opposite effect on these invaders.

Keywords

BEF-China; Early-Successional Communities; Exotic Seed-Addition; Fertilizer Application

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	Tilman, D. (2000) Causes, consequences and ethics of biodi-versity. Nature, 405, 208-211. doi:10.1038/35012217
[2]	Loreau, M., Naeem, S., Inchausti, P., Bengtsson, J., Grime, J.P., Hector, A., Hooper, D.U., Huston, M.A., Raffaelli, D., Schmid, B., Tilman, D. and Wardle, D.A. (2001) Biodiversity and ecosystem functioning: Current knowledge and future challenges. Science, 294, 804-808. doi:10.1126/science.1064088
[3]	Balvanera, P., Pfisterer, A.B., Buchmann, N., He, J.S., Nakashizuka, T., Raffaelli, D. and Schmid, B. (2006) Quantifying the evidence for biodiver-sity effects on ecosystem functioning and services. Ecology Let-ters, 9, 1146- 1156. doi:10.1111/j.1461-0248.2006.00963.x
[4]	Hillebrand, H. and Matthiessen, B. (2009) Biodiversity in a complex world: Con-solidation and progress in functional biodiversity research. Ecology Letters, 12, 1405- 1419. doi:10.1111/j.1461-0248.2009.01388.x
[5]	Tilman, D. (1997) Community invasibility, recruitment limitation, and grassland biodiversity. Ecology, 78, 81-92. doi:10.1890/0012-9658(1997)078[0081:CIRLAG]2.0.CO;2
[6]	Hector, A., Schmid, B., Beierkuhnlein, C., Caldeira, M.C., Diemer, M., Dimitrakopoulos, P.G., Finn, J.A., Freitas, H., Giller, P.S., Good, J., Harris, R., Hogberg, P., Huss-Danell, K., Joshi, J., Jumpponen, A., Korner, C., Leadley, P.W., Loreau, M., Minns, A., Mulder, C.P.H., O’Donovan, G., Otway, S.J., Pereira, J.S., Prinz, A., Read, D.J., Scherer- Lorenzen, M., Schulze, E.D., Siamantziouras, A.S.D., Spehn, E.M., Terry, A.C., Troumbis, A.Y., Woodward, F.I., Yachi, S. and Lawton, J.H. (1999) Plant diversity
[7]	Hector, A., Dobson, K., Minns, A., Bazeley-White, E. and Lawton, J.H. (2001) Community diversity and invasion resistance: An experimental test in a grassland ecosystem and a review of comparable stud-ies. Ecological Research, 16, 819-831. doi:10.1046/j.1440-1703.2001.00443.x
[8]	Roscher, C., Schmid, B. and Schulze, E.D. (2009) Non- random recruitment of invader species in experimental grasslands. Oikos, 118, 1524-1540. doi:10.1111/j.1600-0706.2009.17601.x
[9]	Lu, X., Mo, J. and Dong, S. (2008) Effects of nitrogen deposition on forest biodi-versity. Acta Ecologica Sinica, 28, 5532-5548. doi:10.1016/S1872-2032(09)60012-3
[10]	Bobbink, R., Hicks, K., Galloway, J., Spranger, T., Alkemade, R., Ashmore, M., Bustamante, M., Cinderby, S., Davidson, E., Dentener, F., Em-mett, B., Erisman, J.W., Fenn, M., Gilliam, F., Nordin, A., Pardo, L. and De Vries, W. (2010) Global assessment of nitro-gen deposition effects on terrestrial plant diversity: A synthesis. Journal of Applied Ecology, 20, 30-59. doi:10.1890/08-1140.1
[11]	Lu, X.K., Mo, J.M., Gilliam, F.S., Zhou, G.Y. and Fang, Y.T. (2010) Effects of experimental ni-trogen additions on plant diversity in an old-growth tropical forest. Global Change Biology, 16, 2688-2700. doi:10.1111/j.1365-2486.2010.02174.x
[12]	Barthlott, W., Mutke, J., Rafiqpoor, M.D., Kier, G. and Kreft, H. (2005) Global centres of vascular plant diversity. Nova Acta Leopold-ina, 92, 61-83.
[13]	Zheng, X., Fu, C., Xu, X., Yan, X., Huang, Y., Han, S., Hu, F. and Chen, G. (2002) The Asian nitrogen cycle case study. Ambio, 31, 79-87. doi:10.1579/0044-7447-31.2.79
[14]	Galloway, J.N., Dentener, F.J., Capone, D.G., Boyer, E.W., Howarth, R.W., Seitzinger, S.P., Asner, G.P., Cleveland, C.C., Green, P.A., Holland, E.A., Karl, D.M., Michaels, A.F., Porter, J.H., Townsend. A.R. and Vorosmarty, C.J. (2004) Nitrogen cycles: Past, present, and future. Biogeochemistry, 70, 153-226. doi:10.1007/s10533-004-0370-0
[15]	Lopez-Pujol, J., Zhang, F.M. and Ge, S. (2006) Plant biodiversity in China: Richly varied, endangered, and in need of conservation. Biodiversity and Conservation, 15, 3983-4026. doi:10.1007/s10531-005-3015-2
[16]	Fu, Y, Chen, J, Guo, H., Hu, H., Chen, A. and Cui, J. (2010) Agrobiodiversity loss and livelihood vulnerability as a consequence of converting from subsistence farming systems to commercial planta-tion-dominated systems in Xishuangbanna, Yunnan, China: A household level Ana- lysis. Land Degradation & Development, 21, 274-284.
[17]	Liu, J., Liang, S.C., Liu, F.H., Wang, R.Q. and Dong, M. (2005) Invasive alien plant species in China: Regional distribution patterns. Diversity and Distributions, 11, 341- 347. doi:10.1111/j.1366-9516.2005.00162.x
[18]	Weber, E., Sun, S.G. and Li, B. (2008) Invasive alien plants in China: Diversity and ecological insights. Biological Invasions, 10, 1411-1429. doi:10.1007/s10530-008-9216-3
[19]	Feng, J. and Zhu, Y. (2010) Alien invasive plants in China: Risk assessment and spatial patterns. Biodiversity and Conservation, 19, 3489-3497. doi:10.1007/s10531-010-9909-7
[20]	Mack, R.N., Simberloff, D., Lonsdale, W.M., Evans, H., Clout, M. and Bazzaz, F.A. (2000) Biotic invasions: Causes, epidemiology, global conse-quences, and control. Journal of Applied Ecology, 10, 689-710. doi:10.1890/1051-0761(2000)010[0689:BICEGC]2.0.CO;2
[21]	Meiners, S.J., Pickett, S.T.A. and Cadenasso, M.L. (2001) Effects of plant invasions on the species richness of abandoned agricultural land. Ecography, 24, 633-644. doi:10.1111/j.1600-0587.2001.tb00525.x
[22]	Hejda, M., Pysek, P. and Jarosik, V. (2009) Impact of invasive plants on the species richness, diversity and composition of invaded communities. Journal of Ecology, 97, 393-403. doi:10.1111/j.1365-2745.2009.01480.x
[23]	Wang, X.H., Kent, M. and Fang, X.F. (2007) Evergreen broad-leaved forest in Eastern China: Its ecology and con- servation and the impor-tance of resprouting in forest restoration. Forest Ecology and Management, 245, 76-87. doi:10.1016/j.foreco.2007.03.043
[24]	Song, C. and Zhang, Y. (2010) Forest cover in China from 1949 to 2006, In: Nagendra, H. and Southworth, J. Eds., Reforesting Landscapes: Linking Pattern and Proc- ess, Landscape Series 10, Springer, Dordrecht, 341-356.
[25]	Brockerhoff, E.G., Jactel, H., Par-rotta, J.A., Quine, C.P. and Sayer, J. (2008) Plantation forests and biodiversity: Oxymoron or opportunity? Biodiversity and Conservation, 17, 925-951. doi:10.1007/s10531-008-9380-x
[26]	Knight, K.S., Oleksyn, J., Jagodzinski, A.M., Reich, P.B. and Kasprowicz, M. (2008) Overstorey tree species regu- late colonization by native and exotic plants: A source of positive relationships between under-storey diversity and invasibility. Diversity and Distributions, 14, 666-675. doi:10.1111/j.1472-4642.2008.00468.x
[27]	Gilliam, F.S. (2007) The ecological significance of the herbaceous layer in temperate forest ecosystems. BioScience, 57, 845-858. doi:10.1641/B571007
[28]	M?lder, A., Bernhardt-R?mermann, M. and Schmidt, W. (2008) Herb-layer diversity in deciduous forests: Raised by tree richness or beaten by beech? Forest Ecology and Management, 256, 272-281. doi:10.1016/j.foreco.2008.04.012
[29]	Compagnoni, A. and Halpern, C.B. (2009) Properties of native plant communities do not determine exotic success during early forest succession. Ecography, 32, 449-458. doi:10.1111/j.1600-0587.2008.05739.x
[30]	Chandy, S. and Gibson, D.J. (2009) Scale dependency of species composition and environmental variables in the strata of a deciduous forest. Community Ecology, 10, 121- 130. doi:10.1556/ComEc.10.2009.1.14
[31]	Bruelheide, H., B?hnke, M., Both, S., Fang, T., Assmann, T., Baruffol, M., Bauhus, J., Buscot, F., Chen, X.Y., Ding, B.Y., Durka, W., Erfmeier, A., Fischer, M., Gei?ler, C., Guo, D., Guo, L.D., H?rdtle, W., He, J.S., Hector, A., Kr?ber, W., Kühn, P., Lang, A.C., Nadrowski, K., Pei, K., Scherer-Lorenzen, M., Shi, X., Scholten, T., Schuldt, A., Trogisch, S., von Oheimb, G., Welk, E., Wirth, C., Wu, Y.T., Yang, X., Zeng, X., Zhang, S., Zhou, H., Ma, K. and Schmid, B. (2011) Community assembly during secondary
[32]	Duffy, J.E., Cardinale, B.J., France, K.E., McIntyre, P.B., Thebault, E. and Loreau, M. (2007) The functional role of biodiversity in ecosystems: In-corporating trophic complexity. Ecology Letters, 10, 522-538. doi:10.1111/j.1461-0248.2007.01037.x
[33]	Reiss, J., Bridle, J.R., Montoya, J.M. and Woodward, G. (2009) Emerging hori-zons in biodiversity and ecosystem functioning research. Trends in Ecology & Evolution, 24, 505-514. doi:10.1016/j.tree.2009.03.018
[34]	Srivastava, D.S., Cardi-nale, B.J., Downing, A.L., Duffy, J.E., Jouseau, C., Sankaran, M. and Wright, J.P. (2009) Diversity has stronger top-down than bottom-up effects on decomposition. Ecology, 90, 1073-1083. doi:10.1890/08-0439.1
[35]	Scherber, C., Eisenhauer, N., Weisser, W.W., Schmid, B., Voigt, W., Fischer, M., Schulze, E.D., Roscher, C., Weigelt, A., Allan, E., Bessler, H., Bon-kowski, M., Buchmann, N., Buscot, F., Clement, L.W., Ebeling, A., Engels, C., Halle, S., Kertscher, I., Klein, A.M., Koller, R., Konig, S., Kowalski, E., Kummer, V., Kuu, A., Lange, M., Lau-terbach, D., Middelhoff, C., Migunova, V.D., Milcu, A., Muller, R., Partsch, S., Petermann, J.S., Renker, C., Rottstock, T., Sa-bais, A., Scheu, S., Schumacher, J., Tempert
[36]	Schimpf, D.J. and Danz, N.P. (1999) Light passage through leaf litter: Variation among northern hardwood trees. Agricultural and Forest Meteorology, 97, 103-111. doi:10.1016/S0168-1923(99)00064-7
[37]	Sariyildiz, T., Anderson, J.M. and Kucuk, M. (2005) Effects of tree species and topography on soil chemistry, litter quality, and decompo-sition in Northeast Turkey. Soil Biology & Biochemistry, 37, 1695-1706. doi:10.1016/j.soilbio.2005.02.004
[38]	Gilliam, F.S., Roberts and M.R. (2003) Interactions between the herbaceous layer and overstory canopy of Eastern forests. In: Gilliam, F.S., Roberts, M.R. Eds., The Herbaceous Layer in Forests of Eastern North America. Oxford University Press, Oxford, 198-223.
[39]	H?rdtle, W., von Oheimb, G. and Westphal, C. (2003) The effects of light and soil conditions on the species richness of the ground vegetation of deciduous forests in north-ern Germany (Schleswig-Holstein). Forest Ecology and Ma- nagement, 182, 327-338. doi:10.1016/S0378-1127(03)00091-4
[40]	Naeem, S., Knops, J.M.H., Tilman, D., Howe, K.M., Kennedy, T. and Gale, S. (2000) Plant diversity increases resistance to invasion in the absence of covarying extrinsic factors. Oikos, 91, 97-108. doi:10.1034/j.1600-0706.2000.910108.x
[41]	van Ruijven, J., De Deyn, G.B. and Berendse, F. (2003) Diversity reduces in-vasibility in experimental plant communities: The role of plant species. Ecology Letters, 6, 910-918. doi:10.1046/j.1461-0248.2003.00516.x
[42]	Emery, S.M. and Gross, K.L. (2006) Dominant species identity regulates invasi-bility of old-field plant communi- ties. Oikos, 115, 549-558. doi:10.1111/j.2006.0030-1299.15172.x
[43]	Jiang, X.L., Zhang, W.G. and Wang, G. (2007) Biodiver- sity effects on biomass production and invasion resistance in annual versus perennial plant communities. Biodiver- sity and Conservation, 16, 1983-1994. doi:10.1007/s10531-006-9061-6
[44]	Thomsen, M.A., D’Antonio, C.M., Suttle, K.B. and Sou- sa, W.P. (2006) Eco-logical resistance, seed density and their interactions determine patterns of invasion in a California coastal grassland. Ecology Letters, 9, 160-170. doi:10.1111/j.1461-0248.2005.00857.x
[45]	Eppstein, M.J. and Molofsky, J. (2007) Invasiveness in plant communities with feedbacks. Ecology Letters, 10, 253-263. doi:10.1111/j.1461-0248.2007.01017.x
[46]	Gilliam, F.S. (2006) Response of the herbaceous layer of forest ecosystems to excess nitrogen deposition. Journal of Ecology, 94, 1176-1191. doi:10.1111/j.1365-2745.2006.01155.x
[47]	Jandt, U., von Wehrden, H. and Bruelheide, H. (2011) Exploring large vegeta-tion databases to detect temporal trends in species occurrences. Journal of Vegetation Science, 22, 957-972. doi:10.1111/j.1654-1103.2011.01318.x
[48]	Luken, J.O. (2003) Invasions of forests in the eastern United States. In: Gilliam, F.S., Roberts, M.R. Eds., The Herbaceous Layer in Forests of Eastern North America. Oxford University Press, Oxford, 283-301.
[49]	Fridley, J.D. (2002) Resource availability dominates and alters the relationship between species diversity and ecosystem productivity in experimental plant communities. Oecologia, 132, 271-277. doi:10.1007/s00442-002-0965-x
[50]	Meiners, S.J., Pickett, S.T.A. and Cadenasso, M.L. (2002) Exotic plant invasions over 40 years of old field successions: Community patterns and associations. Ecography, 25, 215-223. doi:10.1034/j.1600-0587.2002.250209.x
[51]	Liu, J., Dong, M., Miao, S.L., Li, Z.Y., Song, M.H. and Wang, R.Q. (2006) Inva-sive alien plants in China: Role of clonality and geographical origin. Biological Invasions, 8, 1461-1470. doi:10.1007/s10530-005-5838-x