caa a22 4500 467902364 CHVBK 20180406152822.0 cr unu---uuuuu 170328e20060501xx s 000 0 eng 10.1007/s10661-006-7231-3 doi (NATIONALLICENCE)springer-10.1007/s10661-006-7231-3 Agricultural Lakes in Finland: Current Water Quality and Trends [Elektronische Daten] [P. Ekholm, S. Mitikka] Agriculture is the largest source of nutrients into surface waters in Finland, and yet relatively little is known about the actual impact of the agricultural load on the state of lakes. We analysed the water quality data of 20 Finnish agricultural lakes and found that they had higher levels of nutrients, chlorophyll a and turbidity than did the other types of lakes (e.g. those receiving point-source load) in the national monitoring network (the Finnish Eurowaternet). Currently, six of the agricultural lakes can be classified as eutrophic and 14 as hypertrophic. Trend analysis (based on Kendall's tau-b) indicated that during 1976-2002 the water quality of the lakes either remained constant or showed signs of increasing eutrophication and elevated turbidity. Decreasing nutrient concentrations were found only in one intensively restored lake. In none of the lakes had the chlorophyll a concentration decreased. The results of the trend analysis are compatible with the recent finding that, despite vigorous efforts, the nutrient load from agriculture has not declined in Finland. Recovery of the most eutrophied agricultural lakes would call for a drastic reduction in the external nutrient load, possibly supplemented with in-lake restoration. Springer Science + Business Media, Inc., 2006 agriculture nationallicence eutrophication nationallicence lakes nationallicence trend analysis nationallicence water quality nationallicence Ekholm P. Finnish Environment Institute, 00251, Helsinki, Finland aut Mitikka S. Finnish Environment Institute, 00251, Helsinki, Finland aut Environmental Monitoring and Assessment Kluwer Academic Publishers 116/1-3(2006-05-01), 111-135 0167-6369 116:1-3<111 2006 116 10661 https://doi.org/10.1007/s10661-006-7231-3 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10661-006-7231-3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Ekholm P. Finnish Environment Institute, 00251, Helsinki, Finland aut NATIONALLICENCE 700 1- Mitikka S. Finnish Environment Institute, 00251, Helsinki, Finland aut NATIONALLICENCE 773 0- Environmental Monitoring and Assessment Kluwer Academic Publishers 116/1-3(2006-05-01), 111-135 0167-6369 116:1-3<111 2006 116 10661 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer