Sager Lionel
Laboratory of Ecology and Aquatic Biology (LEBA), University of Geneva, Chemin des Clochettes 18, CH-1206 Geneva, Switzerland.
Water Res. 2009 Apr;43(6):1667-79. doi: 10.1016/j.watres.2008.12.042. Epub 2009 Jan 3.
The monitoring of the water quality is a major environmental concern and specific method of assessment needs to be addressed for ponds. Among threats on freshwater, eutrophication remains an important and widespread problem. To assess if the trophic state of ponds can be significantly predicted by physico-chemical surrogates, parallel measurements of water physico-chemistry and of summer rates of periphytic net primary productivity (NPP) were performed on a set of nine lowland Swiss ponds representing the whole spectrum of trophic states. The developed methods to measure periphytic NPP on artificial substrates give similar values between the pseudo-replicates and are functional for ponds. The winter concentration of total nitrogen (TN) in the water is a significant predictor of the average summer rates of NPP while in submerged macrophyte beds total phosphorus (TP) is a better predictor. Rates of NPP measured in open water were most often higher and water transparency lower than in macrophyte beds, highlighting the positive influence of macrophytes on water quality and a possible co-occurrence in a pond of contrasting conditions when submerged species are present. This emphasizes the importance of maintaining or restoring submerged macrophyte stands in ponds to improve the water quality.
水质监测是一个主要的环境问题，需要针对池塘制定具体的评估方法。在对淡水的威胁中，富营养化仍然是一个重要且普遍存在的问题。为了评估池塘的营养状态是否能通过物理化学替代指标显著预测，我们对代表整个营养状态范围的九个瑞士低地池塘进行了水物理化学和夏季周丛净初级生产力（NPP）速率的平行测量。在人工基质上测量周丛NPP的方法在伪重复之间给出了相似的值，并且对池塘是有效的。水中总氮（TN）的冬季浓度是NPP夏季平均速率的显著预测指标，而在沉水植物床中，总磷（TP）是更好的预测指标。开阔水域中测量的NPP速率通常高于沉水植物床，且水透明度低于沉水植物床，这突出了大型植物对水质的积极影响，以及当存在沉水物种时池塘中可能同时存在对比条件的情况。这强调了在池塘中维持或恢复沉水植物群落以改善水质的重要性。
