The authors regret that in Table 1, the site BSA was sampled in the years 2008 and 2010, and it was not sampled in the 2015 year. Data of 2015 in the site BSA belong to site Ca. Therefore, the site Ca has data in the years 2010, 2011, 2014 and 2015 and the site BSA has data in the years 2008, 2010.
The authors would like to apologise for any inconvenience caused.
