Laboratoire d'Océanographie Physique et Biogéochimique, Aix-Marseille Université, CNRS, LOPB-UMR 6535, OSU/Centre d'Océanologie de Marseille, Station Marine d'Endoume, 13007 Marseille, France.
Mar Pollut Bull. 2010;61(7-12):480-502. doi: 10.1016/j.marpolbul.2010.06.040.
Coral reef lagoons are under the growing influence of anthropogenic activities, leading to increasing loads of nutrients and various contaminants. Modelling approaches are a useful tool for studying such a complex coastal environment. In this study, we carried out the development of a three-dimensional coupled hydrodynamical-biogeochemical model of the south-west lagoon of New Caledonia. The biogeochemical model presented in Faure et al. (2006, 2010) was dynamically coupled with a hydrodynamical model (MARS3D) in order to study the short-term variability of the ecosystem. Two simulations (in winter and summer) were then performed from measured initial conditions using realistic wind and irradiance conditions and river inputs. Examinations of the biogeochemical response to these transient meteorological conditions were presented and compared with temporal field data corresponding to the considered periods. Results highlighted the ecosystem functioning, based on the balance of hydrodynamical and biogeochemical processes. Influence of urban and terrigeneous inputs were limited to the coastal zone. The model accurately reproduced the measured Chl.a and bacterial production, highlighting the improvement made on the biogeochemical model. However, the underestimation of some variables in model outputs, in particular nutrients, led us to focus on different inputs, such as sediment inputs which were not taken into account or properly estimated. Moreover, the role of boundary waters appeared crucial and suggested a calibration effort. Last, the final aim of our modelling study will help the development of a useful tool for studying the key processes of the ecosystem of the south-west lagoon of New Caledonia, as well as the examination of the biogeochemical response under different scenarios.
珊瑚礁泻湖正受到人为活动的日益影响，导致营养物和各种污染物负荷不断增加。建模方法是研究这种复杂沿海环境的有用工具。在本研究中，我们开发了新喀里多尼亚西南泻湖的一个三维水动力-生物地球化学耦合模型。Faure 等人（2006 年，2010 年）提出的生物地球化学模型与水动力模型（MARS3D）进行了动态耦合，以研究生态系统的短期变化。然后，根据实测的初始条件，使用实际的风和辐射条件以及河流输入，进行了两次模拟（冬季和夏季）。介绍了生物地球化学对这些瞬态气象条件的响应，并与考虑期间的相应时间域数据进行了比较。结果基于水动力和生物地球化学过程的平衡，突出了生态系统的功能。城市和陆源输入的影响仅限于沿海地区。该模型准确地再现了实测的 Chl.a 和细菌生产力，突出了生物地球化学模型的改进。然而，模型输出中一些变量（特别是营养物）的低估促使我们关注不同的输入，例如未考虑或未正确估计的沉积物输入。此外，边界水的作用似乎至关重要，并建议进行校准工作。最后，我们的建模研究的最终目标将有助于开发一种有用的工具，用于研究新喀里多尼亚西南泻湖生态系统的关键过程，并研究不同情景下的生物地球化学响应。
