title: Risk spreading, habitat selection and division of biomass in a submerged clonal plant: responses to heterogeneous copper pollution.
abstract: Heterogeneity of contaminant-stress can be an important environmental factor for clonal plants. We focused on Cu transport among the clones, the foraging or fugitive behavior and biomass allocation of submerged plant, Vallisneria natans (Lour.) Hara, exposed to heterogeneous sediments. This study was carried out in aquatic mesocosms between March and September 2010. Cu accumulated in contaminated ramets was exported horizontally via stolons to other ramets in uncontaminated patches, and then transported both acropetally to leaves and basipetally to belowground structures. There was no indication that V. natans adopted morphological plasticity in response to heterogeneous contaminated habitat. In contrast to predictions, more biomass was allocated to belowground tissues in contaminated patches. We concluded that risk of Cu stress spread among submerged clones, and V. natans did not actively select habitat in contaminated patchy environment. Furthermore, V. natans adopted compensatory investments instead of division of labor to acquire nutrient and survive.
authors.affiliation: Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China. yanxue@whu.edu.cn
authors.forename: Xue
authors.initials: X
authors.lastname: Yan
authors.forename: Haowen
authors.initials: H
authors.lastname: Wang
authors.forename: Qingfeng
authors.initials: Q
authors.lastname: Wang
authors.forename: Lars G
authors.initials: LG
authors.lastname: Rudstam
mesh_terms: D018533:Biomass; D003300:Copper / Q000633:toxicity*; D017753:Ecosystem; D019015:Geologic Sediments / Q000737:chemistry; D031321:Hydrocharitaceae / Q000187:drug effects / Q000502:physiology*; D013312:Stress, Physiological; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical; D003300:Copper