Great Lake is the largest of 14 lakes situated in Lurë National Park, in the eastern part of the Lurë Mountains, Albania. To characterize lake ecological status, epiphytic and epilithic diatom samples were collected from the lakeshore in summer 2005, 2013, and 2017. However, in 2017 no macrophytes were present, such that only epilithic diatom samples could be collected. After laboratory analysis, 52 diatom taxa were identified in July 2005, 67 in June 2013, 111 in August 2013, and 126 in August 2017. The genera Diatoma, Epithemia, Fragilaria, and Surirella were not recorded in 2017, contrary to previous years. We applied two diatom indices to asses the ecological status of the Great Lake, IPS (Indice de Polluo–sensibilité), and TDIL (Trophic Diatom Index for lakes). The IPS index indicated very good water quality in all years, while the TDIL indicated moderate water quality in 2005 and 2013 and good water quality in 2017. Because more species have indicator values for calculating the IPS than the TDIL (valve number used to calculate the IPS was above 95%, while for TDIL was below 50% of 400 counted valves), the IPS may be a more promising tool for bioindication of lakes in Albania according to the demands of the Water Framework Directive.

五大湖是位于阿尔巴尼亚卢拉山脉东部的卢拉国家公园内14个湖泊中最大的。为了表征湖泊的生态状况，在2005年，2013年和2017年夏季从湖岸采集了附生硅藻和上石藻硅藻样品。但是，在2017年，没有大型植物，因此只能采集上石藻硅藻样品。经过化验分析，52硅藻类群67 2005年7月，被确定在111 2013年6月，在2013年，和126在八月2017年八月的属Diatoma，Epithemia，脆，和双菱与往年相反，2017年没有记录。我们应用了两个硅藻指数来评估大湖的生态状况，即IPS（Indice dePolluo-sensibilité）和TDIL（湖泊的营养硅藻指数）。IPS指数显示所有年份的水质都很好，而TDIL则显示2005和2013年的水质中等，2017年则是良好的水质。因为与TDIL（用于计算水质指数的阀数）相比，有更多物种具有IPS指标值IPS高于95％，而TDIL却低于400个计数阀的50％），根据水框架指令的要求，IPS可能是阿尔巴尼亚湖泊生物指示的更有前途的工具。