National Park Service/Everglades Program Team, c/o A.R.M. Loxahatchee National Wildlife Refuge, 10216 Lee Road, Boynton Beach, FL 33437-9741, USA.
Environ Manage. 2012 Mar;49(3):720-33. doi: 10.1007/s00267-011-9798-x. Epub 2011 Dec 30.
Recent appearance of cattail (Typha domingensis) within a southern Everglades slough-Upper Taylor Slough (Everglades National Park)-suggests ecosystem eutrophication. We analyze water quality, nutrient enrichment, and water management operations as potential drivers of eutrophication in Upper Taylor Slough. Further, we attempt to determine why surface water phosphorus, a parameter used commonly to monitor ecosystem health in the Everglades, did not serve as an early warning for eutrophication, which has broader implication for other restoration efforts. We found that surface water total phosphorus concentrations generally were below a 0.01 mg L(-1) threshold determined to cause imbalances in flora and fauna, suggesting no ecosystem eutrophication. However, assessment of nutrient loads and loading rates suggest Upper Taylor Slough has experienced eutrophication and that continued total phosphorus loading through a point-source discharge was a major driver. These nutrient loads, combined with increases in hydroperiods, led to the expansion of cattail in Upper Taylor Slough. We recommend other metrics, such as nutrient loads, periphyton and arthropod community shifts, and sediment core analyses, for assessing ecosystem health. Monitoring surface water alone is not enough to indicate ecosystem stress.
近年来，泽苔草（Typha domingensis）出现在佛罗里达州南部大沼泽地的一条沼泽地中——上泰勒沼泽（Everglades National Park）——这表明生态系统出现了富营养化。我们分析了水质、养分富集和水管理作业，这些都是上泰勒沼泽富营养化的潜在驱动因素。此外，我们试图确定为什么地表水磷（一种常用于监测大沼泽地生态系统健康的参数）不能作为富营养化的早期预警，这对其他恢复工作具有更广泛的意义。我们发现，地表水总磷浓度通常低于 0.01 毫克/升的阈值，这一阈值会导致动植物失衡，表明生态系统没有富营养化。然而，养分负荷和负荷率的评估表明，上泰勒沼泽已经经历了富营养化，并且通过点源排放持续的总磷负荷是主要驱动因素。这些养分负荷，加上水文周期的增加，导致泽苔草在上泰勒沼泽中的扩张。我们建议使用其他指标，如养分负荷、附生生物和节肢动物群落变化以及沉积物芯分析，来评估生态系统健康状况。仅监测地表水不足以表明生态系统受到压力。
