TY - JOUR T1 - Continuous separation of land use and climate effects on the past and future water balance JF - Journal of Hydrology Y1 - 2018 A1 - Zipper, Samuel C. A1 - Motew, Melissa A1 - Booth, Eric G. A1 - Chen, Xi A1 - Qiu, Jiangxiao A1 - Kucharik, Christopher J. A1 - Carpenter, Stephen R. A1 - Loheide II, Steven P. KW - Baseflow KW - Climate change KW - Evapotranspiration KW - Land use change KW - Streamflow KW - Urbanization AB - Understanding the combined and separate effects of climate and land use change on the water cycle is necessary to mitigate negative impacts. However, existing methodologies typically divide data into discrete (before and after) periods, implicitly representing climate and land use as step changes when in reality these changes are often gradual. Here, we introduce a new regression-based methodological framework designed to separate climate and land use effects on any hydrological flux of interest continuously through time, and estimate uncertainty in the contribution of these two drivers. We present two applications in the Yahara River Watershed (Wisconsin, USA) demonstrating how our approach can be used to understand synergistic or antagonistic relationships between land use and climate in either the past or the future: (1) historical streamflow, baseflow, and quickflow in an urbanizing subwatershed; and (2) simulated future evapotranspiration, drainage, and direct runoff from a suite of contrasting climate and land use scenarios for the entire watershed. In the historical analysis, we show that ∼60% of recent streamflow changes can be attributed to climate, with approximately equal contributions from quickflow and baseflow. However, our continuous method reveals that baseflow is significantly increasing through time, primarily due to land use change and potentially influenced by long-term increases in groundwater storage. In the simulation of future changes, we show that all components of the future water balance will respond more strongly to changes in climate than land use, with the largest potential land use effects on drainage. These results indicate that diverse land use change trajectories may counteract each other while the effects of climate are more homogeneous at watershed scales. Therefore, management opportunities to counteract climate change effects will likely be more effective at smaller spatial scales, where land use trajectories are unidirectional. VL - 565 UR - http://www.sciencedirect.com/science/article/pii/S0022169418306188 ER - TY - JOUR T1 - Quantifying indirect groundwater-mediated effects of urbanization on agroecosystem productivity using MODFLOW-AgroIBIS (MAGI), a complete critical zone model JF - Ecological Modeling Y1 - 2017 A1 - Zipper, Samuel C. A1 - Soylu, Mehmet Evren A1 - Kucharik, Christopher J. A1 - Loheide II, Steven P. KW - agroecosystem modeling KW - Dynamic vegetation models KW - Groundwater recharge KW - Groundwater-land surface coupling KW - Land use change KW - Urbanization AB - Sustainably accommodating future population growth and meeting global food requirements requires understanding feedbacks between ecosystems and belowground hydrological processes. Here, we introduce MODFLOW-AgroIBIS (MAGI), a new dynamic ecosystem model including groundwater flow, and use MAGI to explore the indirect impacts of land use change (urbanization) on landscape-scale agroecosystem productivity (corn yield). We quantify the degree to which urbanization can indirectly impact yield in surrounding areas by changing the amount of groundwater recharge locally and the water table dynamics at landscape scales. We find that urbanization can cause increases or decreases in yield elsewhere, with changes up to approximately +/− 40% under the conditions simulated due entirely to altered groundwater-land surface interactions. Our results indicate that land use change in upland areas has the largest impact on water table depth over the landscape. However, there is a spatial mismatch between areas with the largest water table response to urbanization elsewhere (upland areas) and locations with the strongest yield response to urbanization elsewhere (midslope areas). This mismatch arises from differences in baseline water table depth prior to urbanization. Yield response to urbanization in lowland areas is relatively localized despite large changes to the vertical water balance due to stabilizing ecohydrological feedbacks between root water uptake and lateral groundwater flow. These results demonstrate that hydrological impacts of land use change can propagate through subsurface flow to indirectly impact surrounding ecosystems, and these subsurface connections should be considered when planning land use at a landscape scale to avoid negative outcomes associated with land use change. VL - 359 SN - 0304-3800 UR - http://www.sciencedirect.com/science/article/pii/S0304380017300789 JO - Ecological Modelling ER - TY - JOUR T1 - From qualitative to quantitative environmental scenarios: Translating storylines into biophysical modeling inputs at the watershed scale JF - Environmental Modelling & Software Y1 - 2016 A1 - Booth, Eric G. A1 - Qiu, Jiangxiao A1 - Carpenter, Stephen R. A1 - Schatz, Jason A1 - Chen, Xi A1 - Kucharik, Christopher J. A1 - Loheide II, Steven P. A1 - Motew, Melissa M. A1 - Seifert, Jenny M. A1 - Turner, Monica G. KW - Biophysical modeling KW - Climate change KW - Land use change KW - scenarios KW - Social-ecological systems KW - Watershed AB - Scenarios are increasingly used for envisioning future social-ecological changes and consequences for human well-being. One approach integrates qualitative storylines and biophysical models to explore potential futures quantitatively and maximize public engagement. However, this integration process is challenging and sometimes oversimplified. Using the Yahara Watershed (Wisconsin, USA) as a case study, we present a transparent and reproducible roadmap to develop spatiotemporally explicit biophysical inputs [climate, land use/cover (LULC), and nutrients] that are consistent with scenario narratives and can be linked to a process-based biophysical modeling suite to simulate long-term dynamics of a watershed and a range of ecosystem services. Our transferrable approach produces daily weather inputs by combining climate model projections and a stochastic weather generator, annual narrative-based watershed-scale LULC distributed spatially using transition rules, and annual manure and fertilizer (nitrogen and phosphorus) inputs based on current farm and livestock data that are consistent with each scenario narrative. VL - 85 SN - 1364-8152 UR - http://www.sciencedirect.com/science/article/pii/S1364815216304935 JO - Environmental Modelling & Software ER - TY - JOUR T1 - Is groundwater recharge always serving us well? Water supply provisioning, crop production, and flood attenuation in conflict in Wisconsin, USA JF - Ecosystem Services Y1 - 2016 A1 - Booth, Eric G. A1 - Zipper, Samuel C. A1 - Loheide II, Steven P. A1 - Kucharik, Christopher J. KW - Crop production KW - Flooding KW - Groundwater KW - Hydrologic services KW - Recharge KW - Water supply AB - Ecosystem service mapping can provide an avenue for making effective land management decisions in a holistic way. However, mapped quantities do not always appropriately represent the ecosystem services that are used by humans. We highlight this issue with a case study of groundwater recharge, water supply, flooding, and agricultural production in an urbanizing agricultural watershed in southern Wisconsin, USA. Groundwater recharge is typically treated as a beneficial ecosystem service or service indicator whose value to humans monotonically increases with the amount of recharge. While appropriate from a water supply perspective, this relationship breaks down when excess groundwater recharge leads to flooding and crop damage. We suggest moving beyond groundwater recharge as a stand-alone ecosystem service, and instead propose that observations and biophysical models should be used to quantify the final service humans receive from groundwater (e.g. reliability of water supply from a municipal well). Integration of such derived, point-based metrics with other ecosystem services that are more easily represented at the landscape scale remains a challenge for regional ecosystem service inventories and analyses. VL - 21, Part A SN - 2212-0416 UR - http://www.sciencedirect.com/science/article/pii/S2212041616302315 JO - Ecosystem Services ER - TY - JOUR T1 - Using evapotranspiration to assess drought sensitivity on a subfield scale with HRMET, a high resolution surface energy balance model JF - Agricultural and Forest Meteorology Y1 - 2014 A1 - Zipper, Samuel C. A1 - Loheide II, Steven P. KW - Drought response KW - Energy balance KW - Evapotranspiration KW - Precision agriculture KW - Spatial heterogeneity KW - Thermal imagery KW - Yield monitoring AB - Abstract Evapotranspiration (ET) rates provide a valuable within-season indicator of plant productivity, as well as data on fluxes of water in a landscape. Applying remote sensing for ET estimation has potential to improve the sustainable management of water resources in agricultural settings. Most current ET models, however, rely on ‘dry’ and ‘wet’ pixels within a given scene to partition turbulent fluxes between latent and sensible heat, thus limiting their ability to map ET throughout the growing season at extremely high (meter scale) spatial resolutions. Here, we develop a field-validated surface energy balance model, High Resolution Mapping of EvapoTranspiration (HRMET), which requires only basic meteorological data, spatial surface temperature and canopy structure data. We use HRMET to estimate ET rates over two commercial cornfields in south-central Wisconsin during the 2012 growing season, which was characterized by severe drought. HRMET results indicate that the magnitude of within-field variability in ET rates was primarily driven by water availability. The application of remotely sensed data to precision agriculture has also been hampered by turnaround time between image acquisition and availability. We introduce relative ET (ETR), which enables comparison of ET rates between image dates by normalizing for variability caused by weather and crop stage. ETR also provides an intuitive, index-like metric for evaluating spatial variability in ET on a subfield scale. ETR maps illuminate persistent patterns in ET across measurement dates that may be driven by soil water availability and topography. ETR is used to develop a novel paired-image technique that can map subfield sensitivity classes to stressors such as drought. Sensitivity class mapping can be used to circumvent issues related to turnaround time to facilitate the incorporation of remotely sensed data into precision agriculture. VL - 197 SN - 0168-1923 UR - http://www.sciencedirect.com/science/article/pii/S0168192314001518 ER -