title: Plant traits and ecosystem effects of clonality: a new research agenda.
abstract: BACKGROUND
  Clonal plants spread laterally by spacers between their ramets (shoot-root units); these spacers can transport and store resources. While much is known about how clonality promotes plant fitness, we know little about how different clonal plants influence ecosystem functions related to carbon, nutrient and water cycling.
  
  
  METHODS
  The response-effect trait framework is used to formulate hypotheses about the impact of clonality on ecosystems. Central to this framework is the degree of correspondence between interspecific variation in clonal 'response traits' that promote plant fitness and interspecific variation in 'effect traits', which define a plant's potential effect on ecosystem functions. The main example presented to illustrate this concept concerns clonal traits of vascular plant species that determine their lateral extension patterns. In combination with the different degrees of decomposability of litter derived from their spacers, leaves, roots and stems, these clonal traits should determine associated spatial and temporal patterns in soil organic matter accumulation, nutrient availability and water retention.
  
  
  CONCLUSIONS
  This review gives some concrete pointers as to how to implement this new research agenda through a combination of (1) standardized screening of predominant species in ecosystems for clonal response traits and for effect traits related to carbon, nutrient and water cycling; (2) analysing the overlap between variation in these response traits and effect traits across species; (3) linking spatial and temporal patterns of clonal species in the field to those for soil properties related to carbon, nutrient and water stocks and dynamics; and (4) studying the effects of biotic interactions and feedbacks between resource heterogeneity and clonality. Linking these to environmental changes may help us to better understand and predict the role of clonal plants in modulating impacts of climate change and human activities on ecosystem functions.
authors.affiliation: Systems Ecology, Department of Ecological Science, Faculty of Earth and Life Sciences, VU University, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands j.h.c.cornelissen@vu.nl.
authors.forename: Johannes H C
authors.initials: JH
authors.lastname: Cornelissen
authors.affiliation: Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, China State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Yao-Bin
authors.initials: YB
authors.lastname: Song
authors.affiliation: School of Nature Conservation, Beijing Forestry University, Beijing 100083, China.
authors.forename: Fei-Hai
authors.initials: FH
authors.lastname: Yu
authors.affiliation: Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, China State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Dong
mesh_terms: D002999:Clone Cells; D017753:Ecosystem; D010944:Plants / Q000378:metabolism*; D019655:Quantitative Trait, Heritable; D012100:Reproduction, Asexual; D012987:Soil
chemical_list: D012987:Soil
keywords: Carbon cycling; clonal plant ecology; effect traits; functional traits; litter decomposition; nutrient; ramet; response–effect trait framework; spacer; spatial heterogeneity; water retention