Average values along the water column of clorophyll a collected in the Lake Bidighinzu

This dataset includes Chlorophyll a concentration in μg/L. Measurements of Chl a were made on discrete water samples collected monthly in the upper 20 meters layer at sampling station Ghiffa (45°58’30’’N; 8°39’09’’E) from January 1984 to December 2018. Chl a measurements derived by spectrophotometric technique in the period from January 1984 to December 2009, while from January 2010 to December 2018 measurements derived from vertical profiling instrument (FluoroProbe).

These data are seven freshwater parameters of Srebarna Lake. They are: water depth (m) of the lake, pH, conductivity, transperance Secchi (m), the amount of NO2, the amount of PO4 (mg/l) and the amount of Chlorophil a (mg/l). They were taken in May, August and November 2012 and these are data for spring, summer and winter season.

This dataset comprises the simultaneous monitoring of about 50 high mountain lakes in the Spanish’s Sierra Nevada carried out in collaboration with government agencies and local communities as part of a citizen science campaign. Standard monitoring protocols were used to collect data on various physical (temperature, pH, dissolved oxygen, water clarity), chemical (nutrients, major cations and anions, chlorophyll a, alkalinity), and biological parameters (bacteria, zooplankton) in two successive years. High mountain lakes are ideal sites to study and understand global change processes. The utilisation of these systems as sentinels of global change can be attributed to various characteristics, such as: modest catchment areas, oligotrophic waters with limited nutrients, remote accessibility, relatively good ecological health, elevated altitudes and harsh environmental conditions, or the presence of relatively uncomplicated biological communities with rapid renewal rates, among others. The involvement of the community in Sierra Nevada Long-Term Monitoring Programs serves as an invaluable complement to scientific endeavours aimed at monitoring environmental changes, as it contributes to alleviate personnel and resource shortcomings (Villar-Argaiz et al. 2022).

Data on biodiversity of Lake Ohrid and Lake Prespa

Data refer to on-site measurements and water samples collected in the mesotrophic eastern and eutrophic western basin of Lake Balaton. The data sets covers various physicochemical variables including water temperature, conductivity, pH, total suspended solids, Secchi depth, light extinction coefficient and chlorophyll a concentration for phytoplankton. Samples were collected with a tubular water column sampler.

Measurements of chlorophyll-a are part of lake monitoring, which is usually carried out by monthly sampling at many regular lake sites (5 to 17 sites depending on the intensity of the measurements over the years). The integrated sample represents the whole water column of this polymictic shallow lake with a mean lake depth of 1.2m. The photometric measurement satisfies the analytical standards of Ö-Norm in Austria.