The study site starts at the mouth of the river (Vlissingen, the Netherlands) and extends to Gent, 160 km from the mouth, where tidal influence is stopped by sluices. The tributaries the Durme and the Rupel, with the Nete , Dijle and Zenne are also under tidal influence and are considered part of the estuary. The natural inundated areas around the river and the valleys up to 5m TAW are also part of the study system.

The Montseny massif is situated 40 km NNE from Barcelona. The mountains cover about an area of 400 km2, about 80% of which is protected as Natural Park. Its highest altitude is 1707m asl. Climatically and biogeographycally Montseny lies in the northern boundary of the Mediterranean region. It is mostly forested, except at the upper reaches. Vegetation shifts altitudinally, with forests of pine, evergreen holm oak and beech, and heathlands and grasslands dominating in this order as altitude increases. The relief is steep and the lithology consists mostly of metamorphic phyllites, schists and granodiorites.

Dataset provides dissolved reactive phosphorus concentrations measured in Lake Santo Parmense between may 2001 and october 2003. Water samples were collected by means of a Ruttner bottle at different depths over the whole water column at the point of maximum depth of the lake. Samples were analysed according to APHA, AWWA, WPCF (1971).

Vestskoven is a 15 km2 ongoing afforestation area located 15 km west of central Copenhagen. Since 1967 arable land has successively been bought up for afforestation in order to establish a large forest area for outdoor activities and wood production. In 1998, afforestation chronosequences in oak (Quercus robur) and Norway spruce (Picea abies) were established as a research platform to quantify soil carbon dynamics, water recharge, nitrogen budgets and ground vegetation species diversity. The soil and grund vegetation species composition were resampled in the chronosequences after 13 years in 2011. Since 2003, an ICP-Forests Level II/Core plot with integrated monitoring under the UN Convention on Long-Range Transboundary Air Pollution (CLRTAP) is placed in an oak stand. Monitoring has developed over time. There is no time limit on the monitoring financed by the Ministry of Environment and Food in Denmark.

Dataset provides information about Total alkalinity (T.Alk. in meq l-1)in Lake Paione Inferiore (LPI) at different layer depths along the water column, at least twice per year (late summer/autumn) during the period 1984-2013. In total 272 records of total alkalinity recorded in LPI for the period are uploaded. Lake Paione Inferiore is a high altitude Alpine lake, located at 2002 m a.s.l. in the Bognanco Valley, Province of Verbania, Piedmont Region, Italy. The Lake has a surface area of 0.86 ha and a maximum depth of 13.5 m. and it is included in the monitoring sites of the UN-ECE Program ICP WATERS (International Cooperative Programme on Assessment and Monitoring of Acidification of Rivers and Lakes)

Dataset provides water transparency measured by means of a Secchi disk in Lake Santo Parmense in 1991.

Dataset provides Total Nitrogen (TN in mg L-1) in Lake Paione Inferiore (LPI) at different layer depths measured at least twice per year (late summer/autumn) during the period 1989-2013. Data for the period 1995-1999 and for 1993 are missing

Dataset provides nitrate concentrations measured in Lake Santo Parmense in 1991. Water samples were collected by means of a Ruttner bottle at different depths over the whole water column at the point of maximum depth of the lake. Samples were analysed by means of the Sodium Salicylate Method (Rodier, 1978).

Dataset provides pH measured in Lake Santo Parmense during the period 2007-2010. Water samples were collected by means of a Ruttner bottle at different depths over the whole water column at the point of maximum depth of the lake. pH was measured by means of a pH meter.

Dataset provides nitrate concentrations measured in Lake Santo Parmense in 1991. Water samples were collected by means of a Ruttner bottle at different depths over the whole water column at the point of maximum depth of the lake. Samples were analysed by means of the Sodium Salicylate Method (Rodier, 1978).