Lake Sanabria ecosystem regime shift (1986-2019)

This dataset has been used to study the ecosystem regime shifts of Lake Sanabria, the largest natural glacial lake in Spain, in a situation of climate change that may affect compliance with ecological quality objectives, even with no significant water quality pressures. It comprises basic data from long-term (1986-2017) and intensive short-term (2015-2017) limnological monitoring of a few relevant state variables related to nutrients balance, primary production of phytoplankton and thermal structure of the water column. Data about recent history of the lake productivity, reconstructed by high-resolution palaeolimnological analysis of a surface sediment core, is provided. Time series analysis over several decades has detected significant conditional heteroscedasticity in the concentrations of parameters such as chlorophyll and oxygen in recent years in relation to lake turnover rates, coinciding with exceptional episodic single-species blooms of some planktonic diatoms. We include precip..., Analytical methods are described in more detail in the associated publications. 
1.       Description of the methodology used to generate the dataset.
1.1   Site:
·         Lake Sanabria, of glacial origin, is the largest natural lake in the Iberian Peninsula (maximum depth 50 m, area 3.536 km2, volume 99.114 hm3, watershed 122.16 km2) located at 1004 m a.s.l. on granitic bedrock. D02 sampling station coordinates: 42° 7' 12.2\" N 6° 42' 27.9\" W.
1.2   Meteorological stations:
·         Puente Porto reservoir (M02 station, 42˚ 7' 1\" N, 6º 49' 52\" W, 1645 m a.s.l)
·         Puebla de Sanabria (AEMET 2770B station, 42˚ 3' 15\" N, 6º 38' 2\" W, 960 m a.s.l)
1.3   Lake physico-chemical and biological data:
·         Long-term lake monitoring (1986-2018) included monthly inlet and outlet samples and profiles in the eastern sub-basin (station D02) for temperature, conductivity, dissolved oxygen, Secchi disk depth, soluble reactive phosphorus (SRP), total phosphorus (TP), nitrate, silica, and chlo...,
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, **Lake Sanabria ecosystem regime shift (1986-2019)**

**DESCRIPTION OF FILES STRUCTURE AND CONTENTS**

We have submitted our lake chemistry data from long-term monitoring 1986-2018 of lake water column (**Lake-Sanabria_water-chemistry_1986-2018.csv**) and biannual intensive monitoring 2015-2017 of lake inlet and outlet (**Lake-Sanabria_water-chemistry_2015-2017.csv**), the biovolume data of the different phytoplankton groups for the period 2015-2017 (**Lake-Sanabria_phytoplankton_Biovolumen_2015-2017.csv**), the chemistry data of a recent sediment core (**Lake-Sanabria_sediment-core-chemistry_2018.csv**), the monthly precipitation for the period 1963-2017 (**Lake-Sanabria_meteorology_1963-2017.csv**), and the data type used in the MapShed model (**Lake-Sanabria_TN-TP-modelling_2015-2017.csv**).

Descriptions:

**Lake-Sanabria_water-chemistry_1986-2018.csv**

* *Date of sampling*: date on which water samples were collected (YYYY-MM-DD) with monthly periodicity.
* *Lake depth sampling*: w...