Turkey Lakes Watershed Study reference list: 2013

13-01 Creed, I.F., K.L. Webster, G.L. Braun, R.A. Bourbonnière and F.D. Beall. Topographically regulated traps of dissolved organic carbon create hotspots of soil carbon dioxide efflux in forests. Biogeochemistry 112 (1-3), 149-164, doi 10.1007/s10533-012-9713-4, 2013.

Summary: Soil samples from three hillslope transects at the TLW were analyzed for dissolved organic carbon (DOC) concentration in order to assess the contribution of topographically distributed DOC to soil CO₂ efflux. Samples of both mobile DOC and sorbed DOC in both surface (freshly fallen leaves (FFL) and forest floor) and near-surface (A-horizon or top 10cm of peat) soils were examined. DOC substrates from near-surface soil were most strongly related to median soil CO₂ efflux, and when combined with FFL, explained 81% of variance in CO₂ efflux. High concentrations of mobile DOC were found at the footslope, and high concentrations of sorbed DOC were found downhill at the toeslope.

13-02 Lawrence, G.B., I.J. Fernandez, D.D. Richter, D.S. Ross, P.W. Hazlett, S.W. Bailey, R. Ouimet, R. A.F. Warby, A.H. Johnson, H. Lin, J.M. Kaste, A.G. Lapenis, and T.J. Sullivan. Measuring environmental change in forest ecosystems by repeated soil sampling: a North American perspective. Journal of Environmental Quality 42 (3), 623-639, doi:10.2134/jeq2012.0378, 2013.

Summary: This paper provides evidence for the use of soil resampling studies and study sites as an essential tool for environmental monitoring and assessment. Repeated sampling can provide insight into large scale issues such as recovery from acidification, long-term N deposition, C sequestration, effects of climate change, impacts from invasive species and the increasing intensification of soil management. The TLW was one of 16 locations noted as using soil resampling methods to assess the impacts of environmental change. The paper also summarizes how temporal and spatial variability can be addressed with a variety of sampling approaches.

13-03 Mengistu, S.G., C.G. Quick and I.F. Creed.   Nutrient export from catchments on forested landscapes reveals complex nonstationary and stationary climate signals.  Water Resources Research 49, doi:10.1002/wrcr.203022012, 2013.

Summary: An analytical framework was used to detect nonstationary and stationary signals in yearly time series of nutrient export in 4 catchments (C35, C38, C37, C50) at the TLW. Both nonstationary and stationary signals were identified, and the combination of both explained the majority of the variation in nutrient export data. The catchment with low-water storage potential and low water loading was most sensitive to nonstationary and stationary climatic oscillations, suggesting that these hydrologic features are characteristic of the most effective sentinels of climate change.