title: [Effects of large-area planting water hyacinth on macro-benthos community structure and biomass].
abstract: The effects on macro-benthos and benthos environment of planting 200 hm2 water hyacinth (E. crassipens) in Zhushan Bay, Lake Taihu, were studied during 8-10 months consecutive surveys. Results indicated that average densities of mollusca (the main species were Bellamya aeruginosa) in far-planting, near-planting and planting area were 276.67, 371.11 and 440.00 ind/m2, respectively, and biomass were 373.15, 486.57 and 672.54 g/m2, respectively, showed that average density and biomass of planting area's were higher than those of others. However, the average density and biomass of Oligochaeta (the main species was Limodrilus hoffmeisteri) and Chironomidae in planting area were lower than that of outside planting area. The density and biomass of three dominant species of benthic animal increased quickly during 8-9 months, decreased quickly in October inside and outside water hyacinth planting area. The reason of this phenomenon could be possible that lots of cyanobacteria cells died and consumed dissolve oxygen in proceed decomposing. Algae cells released lots of phosphorus and nitrogen simultaneously, so macro-benthos died in this environment. The indexes of Shannon-Weaver and Simpson indicated that water environment was in moderate polluted state. On the basis of the survey results, the large-area and high-density planting water hyacinth haven't demonstrated a great impact on macrobenthos and benthos environment in short planting time (about 6 months planting time).
authors.affiliation: Institute of Agricultural Resource and Environment, Jiangsu Academy of Agricultural Science, Nanjing 210014, China. njliugf@yahoo.cn
authors.forename: Guo-Feng
authors.initials: GF
authors.lastname: Liu
authors.forename: Hai-Qin
authors.initials: HQ
authors.lastname: Liu
authors.forename: Zhi-Yong
authors.initials: ZY
authors.lastname: Zhang
authors.forename: Ying-Ying
authors.initials: YY
authors.lastname: Zhang
authors.forename: Shao-Hua
authors.initials: SH
authors.lastname: Yan
authors.forename: Ji-Cheng
authors.initials: JC
authors.lastname: Zhong
authors.forename: Cheng-Xin
authors.initials: CX
authors.lastname: Fan
mesh_terms: D000818:Animals; D044822:Biodiversity; D018533:Biomass; D002681:China; D002683:Chironomidae / Q000145:classification / Q000254:growth & development; D004784:Environmental Monitoring; D005068:Eutrophication; D005618:Fresh Water / Q000032:analysis; D031423:Hyacinthus / Q000254:growth & development* / Q000378:metabolism; D008974:Mollusca / Q000145:classification / Q000254:growth & development*; D009835:Oligochaeta / Q000145:classification / Q000254:growth & development*; D014876:Water Pollution / Q000032:analysis / Q000517:prevention & control*