Temporal--spatial variations of chlorophyll a and primary production in Meiliang Bay, Lake Taihu, China from 1995 to 2003
Temporal--spatial variations of chlorophyll a and primary production in Meiliang Bay, Lake Taihu, China from 1995 to 2003
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DOI：
10.1093/plankt/fbm049
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发表时间：
2007-08
影响因子：
2.1
通讯作者：
Yunlin Zhang;B. Qin;Mingliang Liu
中科院分区：
文献类型：
--
作者：
Yunlin Zhang;B. Qin;Mingliang Liu
关于湖泊初级生产的长期数据集很少，可用于验证生产模型的产出。基于垂直广义生产力模型（VGPM），利用1995 ~ 2003年太湖梅梁湾7个采样点的742个样点，分析了叶绿素a（Chl a）和初级生产力（PPeu）的时空变化特征。估算初级生产力（PPin）的经验模型被用来验证VGPM PPeu和控制PP的主导因素被确定。1996年和1997年梅梁湾的叶绿素a和PPeu值明显高于其他年份，2001年和2003年的叶绿素a和PPeu值明显下降。叶绿素a的峰值出现在夏季（6 - 8月），最低值出现在冬季（1月）。最高的日平均PPeu通常发生在夏季（6月），例外的是在网站1，日平均PPeu峰值发生在春季（4月）。冬季（一月）记录了最低的每日平均PPeu。在梅梁湾，43.0%的年PP发生在仅3个月，从6月到8月。PPeu最大值与最小值的相对差异显著大于Chl a的相应差异。Chl a和PPeu的含量从梅梁湾内到湾外均呈明显的下降趋势，最高的年综合PPeu值出现在靠近梁溪河流入口的1号站点，分别是位于湾外的3号和6号站点的1.85倍和2.14倍。PPeu的日平均变化与Chl a浓度的日平均变化基本一致，表明Chl a浓度可以解释PP的显著变化。梅梁湾真光层年综合PPeu变化范围为3.44 × 104 tC年-1 ~8.59 × 104 tC年-1，总体平均值为5.65 × 104 tC年-1。VGPM PPeu与经验模型PPin之间存在显著的正线性关系[PPin <$$> 0.826（+0.015）PPeu <$272.0（+25.0），r2 <$0.80，n <$742，P，0.0001]。通过考虑水温、光合有效辐射和光周期对PP的影响，VGPM生成的PPeu比仅包含Chl a浓度的经验模型更准确地捕捉了PP的月变化。
There are few long-term data sets on primary production in a lake, which can be used to validate the output from a production model. To address this need, we determined the temporal–spatial variations of chlorophyll a (Chl a) and primary production (PPeu), based on the vertically generalized production model (VGPM) by using 742 samplings at seven sites in Meiliang Bay in Lake Taihu from 1995 to 2003. An empirical model estimating primary production (PPin) was used to validate VGPM PPeu and the dominant factors controlling PP were determined. Markedly higher Chl a and PPeu values were recorded in Meiliang Bay in 1996 and 1997 than in other years and a marked decrease in Chl a and PPeu was found between 2001 and 2003. Peaks of Chl a typically appeared in summer (June–August) and minima occurred in winter (January). The highest daily mean PPeu usually occurred in summer (June); the exception was at site 1, where peak daily mean PPeu occurred in spring (April). The lowest daily mean PPeu was recorded in winter (January). In Meiliang Bay, 43.0% of annual PP occurred in only 3 months, from June to August. The relative difference of maximum and minimum PPeu was markedly larger than the corresponding difference in Chl a. Levels of both Chl a and PPeu were markedly decreased from the inner to the outer areas of Meiliang Bay; the highest annual integrated PPeu was found at site 1, close to the inflow of the River Liangxi and this level was 1.85 and 2.14 times higher than at sites 3 and 6, respectively, that were located in outer Meiliang Bay. The estimated daily mean PPeu variation closely matched with that of the Chl a concentration, implying that Chl a concentration can account for the considerable variation of PP. The annual integrated PPeu of the euphotic zone in Meiliang Bay ranged from 3.44 � 10 4 tC year -1 to 8.59 � 10 4 tC year -1 with an overall mean of 5.65 � 10 4 tC year -1 . A significant positive linear relationship was found between VGPM PPeu and empirical model PPin [PPin ¼ 0.826 (+0.015)PPeu þ 272.0 (+25.0), r 2 ¼ 0.80, n ¼ 742, P , 0.0001]. By considering the effect of water temperature, photosynthetically active radiation and photoperiod on PP, the VGPM- generated PPeu more accurately captured monthly variations than did the empirical model that only included Chl a concentration.