Ecohydrology

Assessment of human pressures and their hydromorphological impacts on lakeshores in Europe

by Klaus Joehnk

Ostendorp, W., Schmieder, K., Jöhnk, K.D., 2004. Assessment of human pressures and hydromorphological impacts on lakeshores in Europe. Ecohydrology and Hydrobiology 4: 379-395.

Effects of water level variations on the dynamics of the reed belts of Lake Constance

by Klaus Joehnk

Schmieder, K., Dienst, M., Ostendorp, W., Jöhnk, K.D., 2004. Effects of water level variations on the dynamics of the reed belts of Lake Constance. Ecohydrology and Hydrobiology 4: 469-480.

Measuring bed shear stress along vegetated river beds using FST-hemispheres

by Roger Falconer - Cardiff University

Paper 111:  Bockelmann-Evans, B. N., Davies, R. and Falconer, R. A. 2008. Measuring bed shear stress along vegetated river beds using FST-hemispheres. Journal of Environmental Management. 68(4), 627-637

Abstract
The measurement of the bed shear stress along vegetated river beds is essential for accurately... more Abstract
The measurement of the bed shear stress along vegetated river beds is essential for accurately predicting the water level, velocity and solute and sediment transport fluxes in computational hydroenvironmental models. Details are given herein of an experimental and theoretical study to determine the bed boundary shear stress along vegetated river beds introducing a novel field measuring method, namely the FliessWasserStammtisch (FST)-hemispheres. Although investigations have been conducted previously for sedimentary channels using the FST-hemispheres, this preliminary study is thought to be the first time that such hemispheres have been used to investigate the bed shear stresses in vegetated channels. FST-hemispheres were first developed by Statzner and Müller (1989) to act as an integrated indicator of the gross hydrodynamic stresses present near the bed. Test and validation data were found to be at least of the same order of magnitude for the stresses predicted from literature for sedimentary channels, with this study establishing the commencement of a database of calibrated FST-hemisphere laboratory data for vegetated channel beds. In a series of experiments depths ranging from 0.1 m to 0.28 m were considered, equating directly to comparable conditions in small rivers or streams. The results of this study provide a basis for enabling the FST-hemispheres to be used to evaluate the boundary shear stress for a wider range of applications in the future, including, in particular, vegetated river beds. 

Modelling hydrological processes influenced by soil, rock and vegetation in a small karst basin of southwest China

by Anas Ghadouani

Zhang, Z. C., X. Chen, A. Ghadouani, and P. Shi. 2011. Modelling hydrological processes influenced by soil, rock and vegetation in a small karst basin of southwest China. Hydrological Processes 25:2456-2470.

Modelling interactions between hydrologic dynamics and biogeochemical processes in a riparian wetland of a low-order stream

by Klaus-Holger Knorr

Link to abstract only. Text available on request.

Low order streams often show complex, nonlinear relationships between hydrologic conditions in the
riparian zone,... more Low order streams often show complex, nonlinear relationships between hydrologic conditions in the
riparian zone, streamflow generation and the chemical signature of the stream water. Dynamic surface and
subsurface flow paths create a mosaic of biogeochemical conditions that affect the transformation and export of
solutes. These relationships are explored in a virtual modelling study of a riparian wetland that links an
integrated surface–subsurface flow model with a stream tube approach for biogeochemical reactions along
individual flow paths. It is shown that the interplay between water table depth and surface micro-topography in
the riparian zone results in distinct shifts between surface and subsurface flow dominance and the development
of specific surface flow connectivity. Distinct nonlinear relationships between water table depth and stream
discharge that reproduce relationships observed in the field were found. Simulated hydrologic dynamics and the
resulting flow paths result in biogeochemical patterns in the riparian zone that are congruent with patterns
observed in the field.

Ecology and Management of the Spring Snowmelt Recession

by joshua viers

Ecohydrological advances and applications in plant–water relations research: a review

by María Susana Alvarado-Barrientos

Co-authored with my advisor, Heidi Asbjornsen and many others

The Monstering of Tamarisk: How Scientists made a Plant into a Problem

by Matt Chew

Journal of the History of Biology 42(2):231-266, May 2009

Dispersal of biota by humans is a hallmark of civilization, but the results are often unforeseen and sometimes costly.... more Dispersal of biota by humans is a hallmark of civilization, but the results are often unforeseen and sometimes costly. Like kudzu vine in the American South, some examples become the stuff of regional folklore. In recent decades, “invasion biology,” conservation-motivated scientists and their allies have focused largely on the most negative outcomes and often promoted the perception that introduced species are monsters. However, cases of monstering by scientists preceded the rise of popular environmentalism. The story of tamarisk (Tamarix spp.), flowering trees and shrubs imported to New England sometime before 1818, provides an example of scientific “monstering” and shows how slaying the monster, rather than allaying its impacts, became a goal in itself. Tamarisks’ drought and salt tolerance suggested usefulness for both coastal and inland erosion control, and politicians as well as academic and agency scientists promoted planting them in the southern Great Plains and Southwest. But when erosion control efforts in Arizona, New Mexico and Texas became entangled with water shortages, economic development during the Depression and copper mining for national defense during World War Two, federal hydrologists moved quickly to recast tamarisks as water-wasting foreign monsters. Demonstrating significant water salvage was difficult and became subsidiary to focusing on ways to eradicate the plants, and a federal interagency effort devoted specifically to the latter purpose was organized and continued until it, in turn, conflicted with regional environmental concerns in the late 1960s.

Changing Perceptions of Change: The Role of Scientists in Tamarix and River Management

by Matt Chew

Stromberg, Juliet C.; Chew, Matthew K.; Nagler, Pamela L.; Glenn, Edward P.  Source: Restoration Ecology, Volume 17, Number 2, March 2009 , pp. 177-186(10)

Initially introduced to western United States to provide ecosystem services such as erosion control, Tamarix by the... more Initially introduced to western United States to provide ecosystem services such as erosion control, Tamarix by the mid-1900s had became vilified as a profligate waster of water. This large shrub continues, today, to be indicted for various presumed environmental and economic costs, and millions of dollars are expended on its eradication. In this review, we examine the role of scientists in driving changes in perceptions of Tamarix from valuable import to vilified invader and (in some instances) back to a productive member of riparian plant communities. Scientists over the years have sustained a negative perception of Tamarix by, among other things, (1) citing outmoded sources; (2) inferring causation from correlative studies; (3) applying conclusions beyond the scope (domain) of the studies; and (4) emphasizing findings that present the species as an extreme or unnatural agent of change. Recent research is challenging the prevailing dogma regarding Tamarix's role in ecosystem function and habitat degradation and many scientists now recommend management shifts from “pest plant” eradication to systemic, process-based restoration. However, prejudice against this and other non-native species persists. To further close the gap between science and management, it is important for scientists to strive to (1) cite sources appropriately; (2) avoid reflexive antiexotic bias; (3) avoid war-based and pestilence-based terminology; (4) heed the levels of certainty and the environmental domain of studies; (5) maintain up-to-date information on educational Web sites; and (6) prior to undertaking restoration or management actions, conduct a thorough and critical review of the literature.