title: [Attenuation of photosynthetically available radiation (PAR) in Meiliang Bay under different winds and waves].
abstract: Based on the successive underwater irradiance measurement in situ from Jul. 12 to 17 in 2003, the attenuation of photosynthetically available radiation (PAR) and euphotic depth in Meiliang Bay were analyzed under different winds and waves. The results showed that the downward PAR attenuation coefficients ranged from 2.63 to 4.7 m(-1), with an average of 3.63 +/- 0.47 x m(-1), and the corresponding euphotic depth ranged from 0.98 to 1.75 m, with an average of 1.29 +/- 0.18 m, which demonstrated that phytoplankton and macrophyte could not grow below 1.5 m due to the lack of adequate solar radiation. The total suspended solids resulted from wind and wave increased the attenuation of light, with the downward attenuation coefficients of PAR being 2.63, 3.72 and 4.37 x m(-1) under small, medium and large wind and wave, respectively. Significant linear correlations were found between transparence, PAR attenuation coefficient, euphotic depth and total suspended solid, especially inorganic suspended solid, while chlorophyll a was the most nonsignificant light attenuator. Multiple stepwise linear regressions showed that inorganic suspended solid was the most important light attenuator dominating the light attenuation in wind-exposed Meiliang Bay.
authors.affiliation: Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China. ylzhang@niglas.ac.cn
authors.forename: Yunlin
authors.initials: Y
authors.lastname: Zhang
authors.forename: Boqiang
authors.initials: B
authors.lastname: Qin
authors.forename: Weimin
authors.initials: W
authors.lastname: Chen
authors.forename: Weiping
authors.initials: W
authors.lastname: Hu
authors.forename: Guang
authors.initials: G
authors.lastname: Gao
authors.forename: Guangwei
authors.initials: G
authors.lastname: Zhu
authors.forename: Liancong
authors.initials: L
authors.lastname: Luo
mesh_terms: D005618:Fresh Water; D010788:Photosynthesis; D010839:Phytoplankton / Q000378:metabolism* / Q000528:radiation effects*; D011874:Radiometry; D013472:Sunlight; D014466:Ultraviolet Rays; D014919:Wind