title: Changed clonal growth form induced by sand burial facilitates the acclimation of Carex brevicuspis to competition.
abstract: Both competition and burial are important factors that influence plant growth and structuring plant communities. Competition intensity may decline with increased burial stress. However, experimental evidence is scarce. The aim of this study was to elucidate the role of burial stress in influencing plant competition by investigating biomass accumulation, biomass allocation, and clonal growth performance of Carex brevicuspis, one of the dominant species in the Dongting Lake wetland in China. The experiment was conducted with two typical wetland species, C. brevicuspis (target plant) and Polygonum hydropiper (neighbor plant), in a target-neighbor design containing three densities (0, 199, and 398 neighbor plants m-2) and two burial depths (0 and 12 cm). The biomass accumulation of C. brevicuspis decreased with increment of P. hydropiper density in the 0 cm burial treatment. However, in the 12 cm burial treatment, biomass accumulation of C. brevicuspis did not change under medium and high P. hydropiper densities. The relative neighbor effect index (RNE) increased with enhancement of P. hydropiper density but decreased with increasing burial depth. The shoot mass fraction decreased with P. hydropiper density in the 12 cm burial treatments, but the root mass fraction was only affected by burial depth. However, the rhizome mass fraction increased with both P. hydropiper density and burial depth. The number of ramets decreased with increasing P. hydropiper density. With increasing burial depth and density, the proportion of spreading ramets increased from 34.23% to 80.44%, whereas that of clumping ramets decreased from 65.77% to 19.56%. Moreover, increased P. hydropiper density and burial depth led to greater spacer length. These data indicate that the competitive effect of P. hydropiper on C. brevicuspis was reduced by sand burial, which was reflected by different patterns of biomass accumulation and RNE at the two burial depth treatments. A change from a phalanx to a guerrilla growth form and spacer elongation induced by sand burial helped C. brevicuspis to acclimate to competition.
authors.affiliation: Key Laboratory of Agro-ecological Processes in Subtropical Region, The Chinese Academy of Sciences, Hunan 410125, China; Dongting Lake Station for Wetland Ecosystem Research, Institute of Subtropical Agriculture, Changsha, 410125, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Li
authors.affiliation: Key Laboratory of Agro-ecological Processes in Subtropical Region, The Chinese Academy of Sciences, Hunan 410125, China; Dongting Lake Station for Wetland Ecosystem Research, Institute of Subtropical Agriculture, Changsha, 410125, China.
authors.forename: Yonghong
authors.initials: Y
authors.lastname: Xie
authors.affiliation: Key Laboratory of Agro-ecological Processes in Subtropical Region, The Chinese Academy of Sciences, Hunan 410125, China; Dongting Lake Station for Wetland Ecosystem Research, Institute of Subtropical Agriculture, Changsha, 410125, China; University of the Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Lianlian
authors.initials: L
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Agro-ecological Processes in Subtropical Region, The Chinese Academy of Sciences, Hunan 410125, China; Dongting Lake Station for Wetland Ecosystem Research, Institute of Subtropical Agriculture, Changsha, 410125, China.
authors.forename: Li
authors.initials: L
authors.lastname: Jiang
authors.affiliation: Key Laboratory of Agro-ecological Processes in Subtropical Region, The Chinese Academy of Sciences, Hunan 410125, China; Dongting Lake Station for Wetland Ecosystem Research, Institute of Subtropical Agriculture, Changsha, 410125, China.
authors.forename: Xinsheng
authors.initials: X
authors.lastname: Chen
authors.affiliation: Key Laboratory of Agro-ecological Processes in Subtropical Region, The Chinese Academy of Sciences, Hunan 410125, China; Dongting Lake Station for Wetland Ecosystem Research, Institute of Subtropical Agriculture, Changsha, 410125, China; University of the Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Baihan
authors.initials: B
authors.lastname: Pan
authors.affiliation: Key Laboratory of Agro-ecological Processes in Subtropical Region, The Chinese Academy of Sciences, Hunan 410125, China; Dongting Lake Station for Wetland Ecosystem Research, Institute of Subtropical Agriculture, Changsha, 410125, China.
authors.forename: Zhengmiao
authors.initials: Z
authors.lastname: Deng
mesh_terms: D000064:Acclimatization / Q000502:physiology*; D000704:Analysis of Variance; D031255:Carex Plant / Q000254:growth & development*; D002681:China; D017753:Ecosystem; D018517:Plant Roots / Q000254:growth & development; D018520:Plant Shoots / Q000254:growth & development; D028502:Polygonum / Q000254:growth & development; D012987:Soil; D013045:Species Specificity; D053833:Wetlands
chemical_list: D012987:Soil
references.citation: Oecologia. 1985 Jun;66(3):417-422
references.pmid: 28310872
references.citation: Ann Bot. 2006 Jul;98(1):187-91
references.pmid: 16687430
references.citation: Ecology. 2014 Jun;95(6):1437-43
references.pmid: 25039207
references.citation: New Phytol. 2004 Jun;162(3):697-704
references.pmid: 33873769
references.citation: Proc Biol Sci. 2007 Oct 7;274(1624):2503-8
references.pmid: 17686725
references.citation: Ying Yong Sheng Tai Xue Bao. 2009 Jun;20(6):1323-8
references.pmid: 19795640
references.citation: Ecol Lett. 2013 May;16(5):695-706
references.pmid: 23363430
references.citation: Proc Biol Sci. 2004 Aug 7;271 Suppl 5:S331-3
references.pmid: 15504009
references.citation: Sci Rep. 2014 Jul 08;4:5612
references.pmid: 25002329
references.citation: Trends Ecol Evol. 1994 May;9(5):191-3
references.pmid: 21236818