title: Temporal pattern in the bloom-forming macroalgae Chaetomorpha linum and Ulva pertusa in seagrass beds, Swan Lake lagoon, North China.
abstract: Seagrasses that are distributed over a large area of the Swan Lake, Weihai, China, support a productive ecosystem. In recent years, however, frequent macroalgal blooms have changed the ecosystem structure and threatened the seagrasses. To understand the bloom-forming macroalgae we conducted a yearly field survey of Swan Lake. Results indicated that the macroalgae Chaetomorpha linum and Ulva pertusa both exhibited a much higher productivity and attained a greater maximum biomass (of 1712±780gDWm(-)(2) and 1511 ± 555 gDW m(-2), respectively) than was the case for the seagrasses. The mean annual atomic ratios of C/N, C/P and N/P in C. linum were 14.31 ± 4.45, 402.82 ± 130.25, and 28.12±2.08, respectively. The δ(15)N values (11.09 ± 0.91‰ for C. linum; 9.27 ± 2.83‰ for U. pertusa) indicated a land-based source of N enrichment to the macroalgal blooms. High concentrations of nitrogen and phosphorus in the lagoon, particularly near the river mouth, supported the blooms.
authors.affiliation: Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, PR China. Electronic address: yizhou@qdio.ac.cn.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
authors.forename: Peng
authors.initials: P
authors.lastname: Liu
authors.affiliation: Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
authors.forename: Feng
authors.initials: F
authors.lastname: Wang
authors.affiliation: Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
authors.forename: Bingjian
authors.initials: B
authors.lastname: Liu
authors.affiliation: Guangxi Institute of Oceanology, Key Laboratory of Marine Biological Technology, Beihai 536000, PR China.
authors.forename: Xujia
authors.initials: X
authors.lastname: Liu
authors.affiliation: Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, PR China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Xu
authors.affiliation: Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, PR China.
authors.forename: Hongsheng
authors.initials: H
authors.lastname: Yang
mesh_terms: D018533:Biomass; D002681:China; D000460:Chlorophyta; D017753:Ecosystem; D004784:Environmental Monitoring; D005068:Eutrophication; D060106:Lakes; D009584:Nitrogen / Q000032:analysis; D010758:Phosphorus / Q000032:analysis; D012624:Seaweed / Q000254:growth & development*; D044445:Ulva / Q000254:growth & development*
chemical_list: D010758:Phosphorus; D009584:Nitrogen
keywords: Algal blooms; Biomass; Impacts; Macroalgae; Nutrients; Seagrass