In this work the Auda marsh, which is part of a system of Iraqi marshes, was sampled to assess the seasonal dynamics and controlling factors of microalgae productivity. The marshes are situated in a hot climate with high seasonal variation near the Arabian Gulf. Physicochemical and biological measurements were taken for water in three areas. Bio-optical models were constructed to describe the primary productivity and chlorophyll-a concentrations in the wet and dry seasons separately and also for the entire area of the Iraqi marshes. The models, as well as almost all measurements, showed high seasonal variation. The mean water temperature was 16 °C in the wet season and 28 °C in the dry season. An almost twofold difference was measured for turbidity and the concentrations of dissolved oxygen and chlorophyll-a for the two seasons. Chlorophyll-a appeared to be a better indicator of ecosystem conditions than primary productivity or biological oxygen demand, according to the results obtained from canonical correlation analysis. Nitrogen or phosphorous did not explain primary productivity or chlorophyll-a to an appreciable extent. Biological variables were related most strongly to water temperature and turbidity, which were the factors most important for controlling phytoplankton productivity in the marshes.

中文翻译：

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季节性变化大的炎热气候下沼泽浮游植物生产力的控制因素

在这项工作中，对作为伊拉克沼泽系统一部分的奥达沼泽进行采样，以评估微藻生产力的季节性动态和控制因素。沼泽位于阿拉伯湾附近，气候炎热，季节变化大。对三个区域的水进行了物理化学和生物测量。生物光学模型构建描述初级生产力和受叶绿素一个单独且也浓度在干湿季节伊拉克沼泽的整个区域。这些模型以及几乎所有的测量结果都显示出很大的季节性变化。雨季平均水温为 16 °C，旱季平均水温为 28 °C。测量的浊度和溶解氧和叶绿素的浓度几乎是两倍的差异。a两个季节。根据从典型相关分析获得的结果，叶绿素a似乎是比初级生产力或生物需氧量更好的生态系统状况指标。氮或磷没有解释初级生产力或受叶绿素一个到可感知的程度。生物变量与水温和浊度的相关性最强，这是控制沼泽浮游植物生产力的最重要因素。