Effects of Timber Harvest on River Food Webs: Physical, Chmical and Biological Responses
Wootton JT. 2012. Effects of Timber Harvest on River Food Webs: Physical, Chmical and Biological Responses. PLos ONE. 7(9):1-12
I compared physical, chemical and biological characteristics of nine rivers running through three timber harvest regimes to investigate the effects of land use on river ecosystems, to determine whether these corresponded to changes linked with downstream location, and to compare the response of different types of indicator variables. Physical variables changed with downstream location, but varied little with timber harvest. Most chemical variables increased strongly with timber harvest but not with downstream location. Most biological variables did not vary systematically with either timber harvest or downstream location. Dissolved organic carbon did not vary with timber harvest or downstream location, but ocrrelated positively with salmonid abundance. Nutrient manipulations revealed no general pattern of nutrient limiation with timber harvest or downstream location. The results suggest that chemical variables most reliably indicate timber harvest impact in these sytems. The biological variables most relevant to human stakeholders were surprisingly insensitive to timber harvest, however, apparently because of decoupling from nutrient responses and unexpectedly weak responses by physical variables. NOTE: Study sites include river sections outside and within Olympic National Park.
- Type
- Journal Article
- Authors
- Wootton, J.
- Units
- OLYM
- Keywords
- Calawah River Watershed, Fisheries, Food Webs, freshwater rivers, Land Use, logging impacts, Sol Duc River Watershed, Timber Harvest, Water Chemistry
- Subjects
- Ecological Framework: Human Use | Point-Source Human Effects | Point-Source Human Effects