Marielundsbäcken, en miljöstudie under tolv månader

Abstract Marielundsbäcken is a small eutrophicated stream north of Halmstad, Sweden. The stream has its springs in a spruce plantation on the ridge Nyårsåsen. It runs thru open, agricultural land where several tributaries join the main stream, and ends where it flows out in the river Suseån. An examination of the water quality was made from eight different sampling points in its tributaries and its main stream, to monitor the levels of the eutrophicating nutrients: phosphorus and nitrogen. The examination was made from December 2014 to November 2015. Chemical tests of the water, and benthic fauna inventory was used to examine the water quality. The ASPT indices were used to assess the ecological status of the river. The indices showed that the water quality was high. The average content of total nitrogen in the watercourses varied from moderate to extremely high levels according to the Swedish Environmental Protection Agency´s values of running waters in Swedish streams (NVV, 2012). Except for one of the sample sites, all sites showed extremely high concentrations of total phosphorus. The average content of total phosphorus varied from moderate to extremely high levels (NVV, 2012). Despite the positive results from the benthic fauna study, the results from the chemical analyses shows that Marielundsbäcken is significantly eutrophicated