Epsilon Archive for Student Projects

Abstract

Headwaters and their riparian zones are recognized as important parts of the boreal ecosystem, both on local and regional scale , they make up over 70% of all stream length globally (Downing et al. 2012). In Sweden, the forest management is saving riparian buffer zones around the streams to maintain the ecosystem services. The artificial waterways constitute over half of all headwater length in Sweden, yet ditches are not included in the policy´s concerned with riparian zones.
This study aims to examine the diversity of plants in riparian zones of streams and ditches, and to understand what factors are driving that diversity. The study is based on data from 96 sites in 8 areas across Sweden. The sites consisted of 3 vegetation ground cover plots and 3 waterway characteristics cross sections each. The sites were chosen to range over different catchment sizes, 0.5-100km2. My research questions was: (1) Are there differences in waterway characteristics or plant diversity between ditches and streams? Do any differences in waterway characteristics explain patterns of plant diversity? (2) Is there a significant correlation between plant diversity and a latitude?
The analysis showed that the only significant difference in waterway characteristic between streams and ditches was water width, yet no relation could be seen between variation in water width and the plant diversity measures. The streams had 28% higher SDI than the ditches, however there was no significant difference in plant diversity between the different catchment sizes. The FGR yielded no significant difference between the types or waterway characteristics. There was a significantly higher plant diversity in northern compared to southern Sweden.
I conclude that while I found a difference in plant diversity between streams and ditches, I could not explain it with water characteristics. Further research is needed to better understand the difference in biodiversity and geomorphology between streams and ditches.