Tilbake til søkeresultatene

MILJØ2015-Norsk miljøforskning mot 2015

VANN: Long term dynamic changes in an alpine-boreal watershed as reflected in the benthic fauna

Tildelt: kr 0,70 mill.

When monitoring freshwater communities, we usually encounter problems due to our inability to separate effects of natural variation, sampling induced uncertainty and human impact. The aim of this study is to test species rich biocommunities for changes in vital parameters such as biodiversity within a 20 years time period. The effects of natural fluctuations and sampling randomness are considered through a general dynamic model for changes in community structure, enabling us to test for additional unnat ural changes. Data on several variables concerning abiotic factors are available for modelling. The test method development described in Diserud & Aagaard (2002) will be continued. Alternative test statistics will be developed for analysing shift in phen ology. The Atna River system is one of the best documented Nordic freshwater eco-systems with respect both to abiotic and biotic factors. The benthic fauna has been followed by larvae sampling each year since 1986, while large scale investigations base d on samples of imagines were performed only in 1986 and 1987. In this project, we want to resample imagines of the chironomid fauna, which is known to comprise at least 125 species along an altitude gradient up to 1280 m asl. and test for significant changes in community structure, species composition and phenology.

Budsjettformål:

MILJØ2015-Norsk miljøforskning mot 2015