Lohse Lab

mimas Kathleen Lohse, Assistant Professor
School of Natural Resources
325 Biological Sciences East (BSE)
The University of Arizona
Tucson, AZ 85721

email: klohse@email.arizona.edu
office: 301c Biological Sciences East
lab: Forbes Building 113 and 111
phone: 520-621-1432 fax:520-621-8801

Welcome to Kathleen Lohse's research webpage at University of Arizona.

I am ecosystem scientist who works at the interface of ecology, earth system science and land use planning studying the processes shaping watersheds and their responses to anthropogenic changes. From this foundation, I tackle the challenges and complexities of sustainability and global change science. My primary research interests include 1) examining the effects of human activities such as nitrogen (N) deposition and land use changes on soil properties and hydrologic transfer of nutrients and sediments to downstream ecosystems, 2) determining the consequences of human-mediated perturbations for river- riparian ecosystems, 3) exploring the interactive controls of vegetation change, management practices, and fire on ecosystem and geomorphological processes, and 4) coupling spatially explicit biophysical models with land use change models to predict cumulative watershed effects.

In this research, we use field and lab experiments to address research questions at the ecosystem scale, and environmental gradients and spatial modeling tools in geographic information systems (GIS) to extrapolate these results to the landscape scale. For more information, read about opportunities, information for prospective graduate students, and current research in the Lohse Biogeochemistry Lab.

Keywords: water quality, biogeochemistry, ecohydrology, ecosystem, watershed, integrated socio-ecological systems, soils, hydrology, land-use change

Consequences of nitrogen additions for soil processes and solution losses Lohse and Matson (2005) examined the effects of short- and long-term nitrogen (N) additions on pattern and regulation of N soil solution losses from two wet tropical forests located at the extreme ends of a well-characterized soil age and fertility gradient in the Hawaiian Islands. This study is the first to show that mature wet tropical forests on volcanic soils respond immediately to first-time N additions with large nitrate solution losses, with more immediate and larger losses from the N-limited forest on the young soils than the P-limited forest on old soils. Long-term N fertilized forests responded to N additions with even greater losses. Differences in hydrological and chemical properties due to soil age were more important than nutrient status in explaining differences in losses between sites. Link to Hydrologic N losses (with permission)

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Access and Resilience Landridge, Christian-Smith and Lohse explored "Access and Resilience: Analyzing the Construction of Social Resilience to the Threat of Water Scarcity". Abstract- Resilience is a vital attribute that characterizes a system’s capacity to cope with stress. Researchers have examined the measurement of resilience in ecosystems and in social–ecological systems, and the comparative vulnerability of social groups. Our paper refocuses attention on the processes and relations that create social resilience. Our central proposition is that the creation of social resilience is linked to a community’s ability to access critical resources. We explore this proposition through an analysis of how community resilience to the stress of water scarcity is influenced by historically contingent mechanisms to gain, control, and maintain access to water. Access is defined broadly as the ability of a community to actually benefit from a resource, and includes a wider range of relations than those derived from property rights alone. We provide a framework for assessing the construction of social resilience and use it to examine, first, the different processes and relations that enabled four communities in northern California to acquire access to water, and second, how access contributed to their differential levels of resilience to potential water scarcity. Legal water rights are extremely difficult to alter, and given the variety of mechanisms that can generate access, our study suggests that strengthening and diversifying a range of structural and relational mechanisms to access water can enhance a community’s resilience to water scarcity.

Link to paper on Access and Resilience

New Collaborative Project- Tradeoffs of Enhanced Urban Runoff-Recharge and Water Quality

Fourteen water-related house and senate bills were introduced to the Arizona state legislature during January 2007 highlighting the importance of proactive management of the state’s limited water supplies. An increasing number of communities in Arizona, such as those within the Sierra Vista Subwatershed, are investigating the potential for enhanced urban ephemeral channel recharge to balance their groundwater consumption and attain sustainable water yields. Currently, water managers (City of Tucson, Sierra Vista) and decision makers (Upper San Pedro Partnership (USPP)) have limited information on the quality of this urban storm recharge and almost no information on how housing age and density may impact this quality.

In this study, we are quantifying how residential development age and density alter the quantity and quality of storm water runoff. Working with our stakeholders/ research partners (City of Tucson, USGS, the Upper San Pedro Partnership, and USDA-ARS,) we will use this information to develop best management practices that evaluate the tradeoffs between enhanced groundwater recharge and the increased possibility of nutrients, pathogens, metals and organic pollutants in surface and groundwater. Our research sites include the Rillito Basin in Tucson and the San Pedro Basin near Sierra Vista and were chosen to help us develop widely applicable tools for water resources managers. (Collaborators- K.Lohse (SNR), P. Brooks, J. McIntosh, T. Meixner (HWR), D. Goodrich (USDA-ARS), J. Leenhouts (USGS). Partners: City of Tucson and Upper San Pedro Partnership foothills

Effects of soil development with time on hydrologic properties and flow paths Lohse and Dietrich (2005) explored the effects of soil development with time on hydrologic properties and flow paths across a soil chronosequence in Hawaii. hawaii

Link to paper in Water Resources Research

Kathleen Lohse at University of Arizona

Integrated Watershed Science and Ecosystem Research (WSER) Lab

Other Labs at U of A