Recolonization patterns of benthic assemblages after relict sand dredging were investigated in an area offshore of Capo d’Anzio (central Tyrrhenian Sea). Surveys were performed before, during, and after dredging in 2007. Sampling stations were located within and outside the dredging site in water depths between 40 and 56 m. Defaunation due to sand extraction was the main impact observed in the inner stations and in stations located in proximity of the dredging site. At the inner stations, 9 months after dredging, a significant increase in species richness and diversity was observed: the sediment removal led to an increase of the sandy sediment fraction, favouring the settlement of sabulicolous species. A decrease in number of individuals and species was also observed in most of the outer stations, probably due to fine sediment redeposition. Recolonization of macrobenthic assemblages was essentially achieved at inner stations both in terms of abundance and species richness, while at outer stations it was still in progress. Results of this study, providing a picture of recovery times and processes in the Tyrrhenian Sea, could be used to develop predictions of the effects of future offshore sand dredging projects in comparable areas. Monitoring programs and research have a key role to provide a more detailed overview of biological recovery processes and times in different regions and with different dredging intensity.

中文翻译：

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在第勒尼安海中部挖沙后底栖组合的重新定殖模式

在Capo d'Anzio（第勒尼安海中部）离岸地区调查了遗迹挖沙后底栖组合的重新定殖模式。在2007年的疏before之前，之中和之后进行了调查。采样站位于疏site地点的内部和外部，水深在40至56 m之间。在内部站和挖泥场附近的站中，由于采砂引起的剥落是主要的影响。在内部站，疏dr后9个月，观察到物种丰富度和多样性显着增加：沉积物的去除导致沙质沉积物比例的增加，有利于球形生物的沉积。在大多数外围站也观察到个体和物种数量的减少，这可能是由于精细的沉积物再沉积所致。大型底栖动物种群的再殖民化基本上是在内部站实现了丰度和物种丰富度，而在外部站仍在进行。这项研究的结果提供了第勒尼安海的恢复时间和过程的图片，可用于预测可比地区未来海上疏sand工程的效果。监测计划和研究在提供更详细的概述不同区域，不同疏intensity强度的生物恢复过程和时间方面具有关键作用。提供第勒尼安海的恢复时间和过程的图片，可用于预测未来可比地区的海上疏sand工程的效果。监测计划和研究在提供更详细的概述不同区域，不同疏intensity强度的生物恢复过程和时间方面具有关键作用。提供第勒尼安海的恢复时间和过程的图片，可用于预测未来可比地区的海上疏sand工程的效果。监测计划和研究在提供更详细的概述不同区域，不同疏intensity强度的生物恢复过程和时间方面具有关键作用。