@article{robinne_hallema_bladon_flannigan_boisrame_brethaut_doerr_di baldassarre_gallagher_hohner_et al._2021, title={Scientists' warning on extreme wildfire risks to water supply}, volume={35}, ISSN={["1099-1085"]}, DOI={10.1002/hyp.14086}, abstractNote={Abstract}, number={5}, journal={HYDROLOGICAL PROCESSES}, author={Robinne, Francois-Nicolas and Hallema, Dennis W. and Bladon, Kevin D. and Flannigan, Mike D. and Boisrame, Gabrielle and Brethaut, Christian M. and Doerr, Stefan H. and Di Baldassarre, Giuliano and Gallagher, Louise A. and Hohner, Amanda K. and et al.}, year={2021}, month={May} }
 @article{robinne_hallema_bladon_buttle_2020, title={Wildfire impacts on hydrologic ecosystem services in North American high-latitude forests: A scoping review}, volume={581}, ISSN={0022-1694}, url={http://dx.doi.org/10.1016/j.jhydrol.2019.124360}, DOI={10.1016/j.jhydrol.2019.124360}, abstractNote={High-latitude forests of North America are characterized by their natural dependence on large and severe wildfires. However, these wildfires also pose a range of social, economic, and environmental risks, with growing concern regarding persistent effects on stream flow volume, seasonal timing of flow, water quality, aquatic ecosystem health, and downstream community drinking water treatment. Here, we present the outcomes of a comprehensive scoping review of post-fire hydrologic studies in high-latitude forests of North America (Canada and Alaska). Our objectives were to (1) create an inventory of studies on post-fire hydrologic effects on surface water; (2) analyze those studies in terms of watershed characteristics and the type and duration of hydrologic effects; (3) identify and evaluate the link between upstream hydrologic effects with hydrologic ecosystem services; and (4) propose a research agenda addressing the link between wildfire science and hydrologic ecosystem services. We screened 2935 peer-reviewed articles and selected 82 studies to include based on their relevance according to a systematic, multi-step selection process. Next, we classified the papers into five themes: (a) runoff volume and flow regimes, (b) erosion and sediment transport, (c) water chemistry, (d) hydromorphology, and (e) aquatic food webs. For each study, we documented location, fire regime, watershed characteristics, and ecosystem services. The annual number of published studies on post-fire hydrology in high-latitude forests and, in particular, those addressing hydrologic ecosystem services, has increased steadily in recent years. Descriptions of wildfire characteristics, watershed characteristics, and effects on hydrologic ecosystem services were highly variable across studies, hindering cross-study comparisons. Moreover, there were limited efforts to extend study results to implications for forest or water management decisions regarding ecosystem services from source watersheds. Most studies focused on fire impacts on aquatic habitats and water chemistry while services of direct concern to communities, such as drinking water, were rarely addressed. We contend that study standardization, further use of geospatial technologies, and more studies directly addressing ecosystem services will help mitigate the increasing risks to water resources in northern forests.}, journal={Journal of Hydrology}, publisher={Elsevier BV}, author={Robinne, François-Nicolas and Hallema, Dennis W. and Bladon, Kevin D. and Buttle, James M.}, year={2020}, month={Feb}, pages={124360} }
 @book{sun_hallema_cohen_mcnulty_caldwell_robinne_norman_liu_2019, place={Research Triangle Park, North Carolina}, title={Effects of wildfires and fuel treatment strategies on watershed water quantity across the Contiguous United States}, url={https://www.firescience.gov/projects/14-1-06-18/project/14-1-06-18_final_report.pdf}, number={14-1-06-18}, institution={Joint Fire Science Program, USDA Forest Service Southern Research Station}, author={Sun, G. and Hallema, D.W. and Cohen, E.C. and McNulty, S.G. and Caldwell, P.V. and Robinne, F.-N. and Norman, S.P. and Liu, Y.}, year={2019}, month={Apr} }
 @article{hallema_kinoshita_martin_robinne_galleguillos_mcnulty_sun_singh_mordecai_moore_2019, place={Rome, Italy}, title={Fire, forests and city water supply}, volume={70}, number={251}, journal={Unasylva}, publisher={Food and Agriculture Organization of the United Nations}, author={Hallema, D.W. and Kinoshita, A.M. and Martin, D.A. and Robinne, F.-N. and Galleguillos, M. and McNulty, S.G. and Sun, G. and Singh, K.K. and Mordecai, R.S. and Moore, P.F.}, year={2019}, pages={58–66} }
 @article{yu_sun_cai_hallema_duan_2019, title={Water Yield Responses to Gradual Changes in Forest Structure and Species Composition in a Subboreal Watershed in Northeastern China}, volume={10}, ISSN={1999-4907}, url={http://dx.doi.org/10.3390/f10030211}, DOI={10.3390/f10030211}, abstractNote={Relationships between forest cover and streamflow have been studied worldwide, but only a few studies have examined how gradual changes in forest structure and species composition due to logging and climate change affect watershed water yield (Q) and flow regimes. In this study, we analyzed long-term (45 years) hydrologic, climate and forest dynamics data from the subboreal Tahe watershed in northeastern China. Our purpose was to evaluate the effects of forest logging and regeneration on changes in forest biomass and species and to quantify the subsequent impact on mean annual streamflow and flow regime under a changing climate. The study watershed was dominated by old-growth larch (Larix gmelinii Rupr.) during the 1970s, but gradually transformed into young deciduous larch mixed with deciduous broad-leaved birch (Betula platyphylla Sukaczev) during the 2010s. During the same period, the watershed experienced climate change with a significant increase in air temperature of 0.028 ℃/year. We applied eight sensitivity-based techniques to separate the effects of climate change on water yield from those due to forest changes. We used flow duration curves (FDCs) to characterize flow regimes by dividing the study into four key periods based on the proportional change of larch and birch trees. We found that the mean annual streamflow decreased by 10 mm (−16 mm attributed to forest change and +6 mm to climate change) between the 1984–1994 period and the 2006–2016 period when the proportion of birch increased by 20% with a similar total forest volume in the later period. The mean annual streamflow increased from 216 mm to 270 mm (+35.5 mm due to forest change vs +17.7 mm due to climate change) when forest volume decreased by 18.7% (17 m3/ha) between the 1970s and 1984–1994. Water yield changed only slightly (3.5 mm) when forest volume increased by 8.7% (6 m3/ha) from 2000 to 2011. In addition, the magnitude of high flow and low flow increased following deforestation and a shift in species composition from a period (1984–1994) with 70% larch with 30% birch to a later period (2006–2016) with 50% larch with 50% birch. Both high flow and low flow decreased coinciding with a reforestation period (2006–2016). Our results highlight complex interactions among climate, forest structure, total biomass, and plant diversity (trees species composition) in influencing watershed hydrology. Further study is needed to examine the effects of ecohydrological processes such as evapotranspiration in larch and birch forests on hydrologic changes across multiple scales.}, number={3}, journal={Forests}, publisher={MDPI AG}, author={Yu, Zhengxiang and Sun, Ge and Cai, Tijiu and Hallema, Dennis and Duan, Liangliang}, year={2019}, month={Feb}, pages={211} }
 @book{hallema_sun_caldwell_robinne_bladon_norman_liu_cohen_mcnulty_2019, title={Wildland fire impacts on water yield across the contiguous United States}, url={http://dx.doi.org/10.2737/srs-gtr-238}, DOI={10.2737/srs-gtr-238}, abstractNote={Wildland fires in the contiguous United States (CONUS) have increased in size and severity, but much remains unclear about the impact of fire size and burn severity on water supplies used for drinking, irrigation, industry, and hydropower. While some have investigated large-scale fire patterns, long-term effects on runoff, and the simultaneous effect of fire and climate trends on surface water yield, no studies account for all these factors and their interactions at the same time. In this report, we present critical new information for the National Cohesive Wildland Fire Management Strategy—a first-time CONUS-wide assessment of observed and potential wildland fire impacts on surface water yield. First, we analyzed data from 168 fire-affected locations, collected between 1984 and 2013, with machine learning and used climate elasticity models to correct for the local climate baseline impact. Stream gage data show that annual river flow increased most in the Lower Mississippi and Lower and Upper Colorado water resource regions, however they do not show which portion of this increase is caused by fire and which portion results from local climate trends. Our machine learning model identified local climate trends as the main driver of water yield change and determined wildland fires must affect at least 19 percent of a watershed >10 km2 to change its annual water yield. A closer look at 32 locations with fires covering at least 19 percent of a watershed >10 km2 revealed that wildfire generally enhanced annual river flow. Fires increased river flow relatively the most in the Lower Colorado, Pacific Northwest, and California regions. In the Lower Colorado and Pacific Northwest regions, flow increased despite post-fire drought conditions. In southern California, post-fire drought effects masked the flow enhancement attributed to wildfire, meaning that annual water yield declined but not as much as expected based on the decline in precipitation. Prescribed burns in the Southeastern United States did not produce a widespread effect on river flow, because the area affected was typically too small and characterized by only low burn severity. In the second stage of the assessment, we performed full-coverage simulations of the CONUS with the Water Supply Stress Index (WaSSI) hydrologic model (88,000 HUC-12-level watersheds) for the period between 2001 and 2010. This enables us to fill in the gaps of areas with scarce data and to identify regions with large potential increases in post-fire annual water yield (+10 to +50 percent): midto high-elevation forests in northeastern Washington, northwestern Montana, central Minnesota, southern Utah, Colorado, and South Dakota, and coastal forests in Georgia and northern Florida. A hypothetical 20-percent forest burn impact scenario for the CONUS suggests that surface yield can increase up to +10 percent in most watersheds, and even more in some watersheds depending on climate, soils, and vegetation. The insights gained from this quantitative analysis have major implications for flood mitigation and watershed restoration, and are vital to forest management policies aimed at reducing fire impact risk and improving water supply under a changing climate.}, institution={U.S. Department of Agriculture, Forest Service, Southern Research Station}, author={Hallema, Dennis and Sun, Ge and Caldwell, Peter and Robinne, Francois-Nicolas and Bladon, Kevin D. and Norman, Steve and Liu, Yongqiang and Cohen, Erika C. and McNulty, Steve}, year={2019} }
 @article{hallema_sun_caldwell_norman_cohen_liu_bladon_mcnulty_2018, title={Burned forests impact water supplies}, volume={9}, ISSN={2041-1723}, url={http://dx.doi.org/10.1038/s41467-018-03735-6}, DOI={10.1038/s41467-018-03735-6}, abstractNote={Abstract}, number={1}, journal={Nature Communications}, publisher={Springer Science and Business Media LLC}, author={Hallema, Dennis W. and Sun, Ge and Caldwell, Peter V. and Norman, Steven P. and Cohen, Erika C. and Liu, Yongqiang and Bladon, Kevin D. and McNulty, Steven G.}, year={2018}, month={Apr} }
 @article{liu_sun_mitra_noormets_gavazzi_domec_hallema_li_fang_king_et al._2018, title={Drought and thinning have limited impacts on evapotranspiration in a managed pine plantation on the southeastern United States coastal plain}, volume={262}, ISSN={0168-1923}, url={http://dx.doi.org/10.1016/j.agrformet.2018.06.025}, DOI={10.1016/j.agrformet.2018.06.025}, abstractNote={Managed and natural coastal plain forests in the humid southeastern United States exchange large amounts of water and energy with the atmosphere through the evapotranspiration (ET) process. ET plays an important role in controlling regional hydrology, climate, and ecosystem productivity. However, long-term studies on the impacts of forest management and climatic variability on forest ET are rare, and our understanding of both external and internal drivers on seasonal and interannual ET variability is incomplete. Using techniques centered on an eddy covariance method, the present study measured year-round ET flux and associated hydrometeorological variables in a drained loblolly pine (Pinus taeda L.) plantation on the lower coastal plain of North Carolina, U.S. We found that annual ET was relatively stable (1076 ± 104 mm) in comparison to precipitation (P) (1168 ± 216 mm) during the 10-year study period when the site experienced extreme climate (2007–2008) and forest thinning (2009). At the seasonal time scale, mean ET/P varied between 0.41 and 1.51, with a mean value of 1.12 ± 0.23 and 0.72 ± 0.16 for the growing and dormant seasons, respectively. The extreme drought during 2007–2008 (mean annual P, 854 mm) only resulted in a slight decrease (∼8%) in annual ET owing to the shallow groundwater common to the study area. Although changes in leaf area index and canopy structure were large after the stand was 50% thinned in the fall of 2009, mean annual ET was similar and averaged 1055 mm and 1104 mm before (2005, 2006 and 2009) and after (2010–2015) thinning, respectively. Data suggested that annual ET recovered within two years of the thinning as a result of rapid canopy closure and growth of understory. Further analysis indicated that available energy was the key driver of ET: approximately 69% and 61% of the monthly variations in ET were explained by net radiation during the dormant and growing seasons, respectively. Overall, we concluded that drought and forest thinning had limited impacts on seasonal and annual ET in this energy limited forest ecosystem with shallow groundwater. The results from this study help to better understand regional ecohydrological processes and projecting potential effects of forest management and extreme climate on water and carbon cycles.}, journal={Agricultural and Forest Meteorology}, publisher={Elsevier BV}, author={Liu, Xiaodong and Sun, Ge and Mitra, Bhaskar and Noormets, Asko and Gavazzi, Michael J. and Domec, Jean-Christophe and Hallema, Dennis W. and Li, Jiyue and Fang, Yuan and King, John S. and et al.}, year={2018}, month={Nov}, pages={14–23} }
 @article{sun_hallema_asbjornsen_2018, title={Preface for the article collection “Ecohydrological Processes and Ecosystem Services”}, volume={7}, ISSN={2192-1709}, url={http://dx.doi.org/10.1186/s13717-018-0120-1}, DOI={10.1186/s13717-018-0120-1}, number={1}, journal={Ecological Processes}, publisher={Springer Science and Business Media LLC}, author={Sun, Ge and Hallema, Dennis W. and Asbjornsen, Heidi}, year={2018}, month={Mar} }
 @article{hallema_robinne_bladon_2018, title={Reframing the Challenge of Global Wildfire Threats to Water Supplies}, volume={6}, ISSN={2328-4277}, url={http://dx.doi.org/10.1029/2018EF000867}, DOI={10.1029/2018EF000867}, abstractNote={Abstract}, number={6}, journal={Earth's Future}, publisher={American Geophysical Union (AGU)}, author={Hallema, Dennis W. and Robinne, François-Nicolas and Bladon, Kevin D.}, year={2018}, month={Jun}, pages={772–776} }
 @article{sun_hallema_asbjornsen_2017, title={Ecohydrological processes and ecosystem services in the Anthropocene: a review}, volume={6}, ISSN={2192-1709}, url={http://dx.doi.org/10.1186/s13717-017-0104-6}, DOI={10.1186/s13717-017-0104-6}, abstractNote={The framework for ecosystem services has been increasingly used in integrated watershed ecosystem management practices that involve scientists, engineers, managers, and policy makers. The objective of this review is to explore the intimate connections between ecohydrological processes and water-related ecosystem services in human-dominated ecosystems in the Anthropocene. We synthesize current literature to illustrate the importance of understanding the ecohydrological processes for accurately quantifying ecosystem services under different environmental and socioeconomic settings and scales. Our synthesis focuses on managed ecosystems that are dominated by humans and explores how ecological processes affect the tradeoffs and synergies of multiple ecosystem services. We identify research gaps in studying ecological processes mainly including energy, carbon, water, and nutrient balances to better assess and quantify ecosystem services that are critical for sustaining natural resources for future generations. To better assess ecosystem services, future ecohydrological studies need to better account for the scaling effects of natural and anthropogenic stressors exerted on evapotranspiration and other water supply and demand processes. Future studies should focus on the bidirectional interactions between hydrological functions and services and human actions to solve real world problems such as water shortages, ecological degradation, and climate change adaptation.}, number={1}, journal={Ecological Processes}, publisher={Springer Science and Business Media LLC}, author={Sun, Ge and Hallema, Dennis and Asbjornsen, Heidi}, year={2017}, month={Oct} }
 @article{hallema_sun_bladon_norman_caldwell_liu_mcnulty_2017, title={Regional patterns of postwildfire streamflow response in the Western United States: The importance of scale‐specific connectivity}, volume={31}, ISSN={0885-6087 1099-1085}, url={http://dx.doi.org/10.1002/hyp.11208}, DOI={10.1002/hyp.11208}, abstractNote={Abstract}, number={14}, journal={Hydrological Processes}, publisher={Wiley}, author={Hallema, Dennis W. and Sun, Ge and Bladon, Kevin D. and Norman, Steven P. and Caldwell, Peter V. and Liu, Yongqiang and McNulty, Steven G.}, year={2017}, month={Jun}, pages={2582–2598} }
 @article{hallema_sun_caldwell_norman_cohen_liu_ward_mcnulty_2016, title={Assessment of wildland fire impacts on watershed annual water yield: Analytical framework and case studies in the United States}, volume={10}, ISSN={1936-0584}, url={http://dx.doi.org/10.1002/eco.1794}, DOI={10.1002/eco.1794}, abstractNote={Abstract}, number={2}, journal={Ecohydrology}, publisher={Wiley}, author={Hallema, Dennis W. and Sun, Ge and Caldwell, Peter V. and Norman, Steven P. and Cohen, Erika C. and Liu, Yongqiang and Ward, Eric J. and McNulty, Steven G.}, year={2016}, month={Nov}, pages={e1794} }
 @article{hould-gosselin_rousseau_gumiere_hallema_ratté-fortin_thériault_van bochove_2016, title={Modeling the sediment yield and the impact of vegetated filters using an event-based soil erosion model-a case study of a small Canadian watershed}, volume={30}, ISSN={0885-6087}, url={http://dx.doi.org/10.1002/hyp.10817}, DOI={10.1002/hyp.10817}, abstractNote={This paper presents the first application of the event‐based MHYDAS‐Erosion model to a small agricultural watershed under temperate climate conditions (Quebec, Canada). Simulation results based on observed and synthetic rainfall events revealed a bimodal behaviour of sediment yield. During high‐intensity rainfall events, most of the sediments reaching the watershed outlet originate from cropland. Meanwhile, during low‐intensity events, most of the sediments come from the drainage network. Furthermore, simulation results show that implementation of 5‐m and 20‐m wide vegetated filters throughout the watershed or at the edge of the most problematic fields (4% of the total fields) could reduce soil loss by 52% and 31%, respectively. The modeling framework could be used for the design and location of beneficial management practices such as grass strips and riparian zones Copyright © 2016 John Wiley & Sons, Ltd.}, number={16}, journal={Hydrological Processes}, publisher={Wiley}, author={Hould-Gosselin, Gabriel and Rousseau, Alain N. and Gumiere, Silvio J. and Hallema, Dennis W. and Ratté-Fortin, Claudie and Thériault, Georges and van Bochove, Eric}, year={2016}, month={Apr}, pages={2835–2850} }
 @inproceedings{hallema_sun_caldwell_norman_cohen_liu_mcnulty_2016, place={Asheville, NC}, title={Relationships between wildland fire and watershed hydrology across the contiguous United States}, ISBN={9781411326163}, url={https://www.fs.usda.gov/treesearch/pubs/50892}, number={SRS-211}, booktitle={Headwaters to estuaries: advances in watershed science and management, March 2-5, 2015, North Charleston, South Carolina : proceedings of the fifth Interagency Conference on Research in the Watersheds}, publisher={U.S. Forest Service, Southern Research Station}, author={Hallema, D.W. and Sun, G. and Caldwell, P.V. and Norman, S.P. and Cohen, E.C. and Liu, Y. and McNulty, S.G.}, editor={Stringer, C.E. and Krauss, K.W. and Latimer, J.S.Editors}, year={2016}, pages={103} }
 @article{hallema_moussa_sun_mcnulty_2016, title={Surface storm flow prediction on hillslopes based on topography and hydrologic connectivity}, volume={5}, ISSN={2192-1709}, url={http://dx.doi.org/10.1186/s13717-016-0057-1}, DOI={10.1186/s13717-016-0057-1}, abstractNote={Hillslopes provide critical watershed ecosystem services such as soil erosion control and storm flow regulation through collecting, storing, and releasing rain water. During intense rainstorms, rainfall intensity and infiltration capacity on the hillslope control Hortonian runoff while the topographic attributes of the hillslope (e.g., slope, aspect, curvature) and the channel network define the structural hydraulic connectivity that determines how rapidly excess water is transferred. This paper discusses literature on the link between topographic attributes and hydrologic connectivity and demonstrates how this link can be used to define a parsimonious model for predicting surface runoff during high intensity rainfall. First, we provide a topographic characterization of the hillslope necessary to determine the structural hydrologic connectivity of surface flow based on existing literature. Subsequently, we demonstrate a hydrologic surface response model that routes the geomorphologic unit hydrograph (GIUH) through a spatial domain of representative elementary hillslopes reflecting the structural hydrologic connectivity. Topographic attributes impact flow and travel time distributions by affecting gravitational acceleration of overland flow and channel, solar irradiance, flow deceleration by vegetation, and flow divergence/convergence. We show with an example where we apply the GIUH-based model to hypothetical hillslopes that the spatial organization of the channel network is critical in the flow and travel time distribution, and that topographic attributes are key in obtaining simple yet accurate representations of hydrologic connectivity. Parsimonious GIUH models of surface runoff that use this hydrologic connectivity have the advantage of low data requirements, being scalable and applicable regardless of the spatial complexity of the hillslope, and have the potential to fundamentally improve flood forecasting tools used in the assessment of ecosystem services.}, number={1}, journal={Ecological Processes}, publisher={Springer Science and Business Media LLC}, author={Hallema, Dennis W. and Moussa, Roger and Sun, Ge and McNulty, Steven G.}, year={2016}, month={Sep} }
 @article{hallema_périard_lafond_gumiere_caron_2015, title={Characterization of Water Retention Curves for a Series of Cultivated Histosols}, volume={14}, ISSN={1539-1663}, url={http://dx.doi.org/10.2136/vzj2014.10.0148}, DOI={10.2136/vzj2014.10.0148}, abstractNote={Water retention curves are essential for the parameterization of soil water models such as HYDRUS. Although hydraulic parameters are known for a large number of mineral and natural organic soils, our knowledge on the hydraulic behavior of cultivated Histosols is rather limited. The objective of this study was to derive characteristic water retention curves for a large cultivated peatland with lettuce (Lactuca sativa L.) and vegetable farming in southern Quebec, Canada. A comparison showed that the van Genuchten model fits better to the water retention data obtained with a Tempe pressure cell experiment than the Groenevelt–Grant model in terms of residual sum of squares; however, the difference in performance was quite small due to the high number of iterations used for fitting. Finally, an agglomerative cluster analysis of 85 peat samples allowed us to define two distinct water retention curves, where the first water retention curve described samples of relatively shallow (<150 cm) Histosols with an organic content <0.89 and a bulk density >0.3 g cm−3, and the second curve characterized samples of the deepest (depth 150–230 cm) Histosols with an organic content of up to 0.97 and a bulk density >0.3 g cm−3, which are the soils that suffered a more dramatic transformation as a result of agriculture. This characterization allows for a multitude of applications, including parameterization of the HYDRUS model for soil water movement, and presents an essential tool for the optimization of water management in cultivated peatlands.}, number={6}, journal={Vadose Zone Journal}, publisher={Wiley}, author={Hallema, Dennis W. and Périard, Yann and Lafond, Jonathan A. and Gumiere, Silvio J. and Caron, Jean}, year={2015}, month={Mar}, pages={1–8} }
 @inproceedings{olivier_paquette_cogliastro_rousseau_messier_revéret_rivest_gumiere_hallema_alam_et al._2015, title={Contribution de systèmes agroforestiers intercalaires à l’adaptation aux changements climatiques des agroécosystèmes (Contribution of tree-based intercropping to climate adaptation of agroecosystems)}, booktitle={Proceedings of the 14th World Forestry Congress}, publisher={Food and Agriculture Organization of the United Nations}, author={Olivier, A. and Paquette, A. and Cogliastro, A. and Rousseau, A. and Messier, C. and Revéret, J.-P. and Rivest, D. and Gumiere, S.J. and Hallema, D.W. and Alam, M. and et al.}, year={2015} }
 @article{hallema_lafond_périard_gumiere_sun_caron_2015, title={Long-Term Effects of Peatland Cultivation on Soil Physical and Hydraulic Properties: Case Study in Canada}, volume={14}, ISSN={1539-1663}, url={http://dx.doi.org/10.2136/vzj2014.10.0147}, DOI={10.2136/vzj2014.10.0147}, abstractNote={Organic soils are an excellent substrate for commercial lettuce (Lactuca sativa L.) farming; however, drainage accelerates oxidation of the surface layer and reduces the water holding capacity, which is often lethal for crops that are sensitive to water stress. In this case study, we analyzed 942 peat samples from a large cultivated peatland complex (18.7 km2) in southern Quebec, Canada, and demonstrated from spatial and temporal patterns that agriculture resulted in a compacted layer below the root zone. We grouped the samples based on the year in which the corresponding fields were created on the previously undisturbed peatland (cutoff years 1970, 1980, 1990, and 2000) and discovered that bulk density has continued to increase, partly due to the overburden pressure, while organic matter has continued to decline since the fields were reclaimed and drained in phases between 1955 and 2006. Saturated hydraulic conductivity (Ks) in the upper 20 cm was remarkably lower on fields older than 10 yr (p = 0.0973 for Wilcoxon rank test), with more samples having a Ks < 2.0 × 10−3 yr. Soil water available capacity (SWAC) was between approximately 5 and 33 cm on fields reclaimed after 2000, while samples from fields reclaimed before 2000 had a lower SWAC between 2 and 23 cm (groups discernable at p = 0.0203). It is possible, however, that the greatest rate of change in Ks and SWAC occurred within even a year of reclamation. The results of this study call for active measures to reduce organic soil degradation such as reducing tillage and on‐field traffic or following a crop rotation scheme.}, number={6}, journal={Vadose Zone Journal}, publisher={Wiley}, author={Hallema, Dennis W. and Lafond, Jonathan A. and Périard, Yann and Gumiere, Silvio J. and Sun, Ge and Caron, Jean}, year={2015}, month={Mar}, pages={vzj2014.10.0147} }
 @inproceedings{périard_gumiere_rousseau_hallema_caron_2015, place={Quebec City, Canada}, title={Predicting soil hydraulic properties from tomodensitometric analysis and particle size distribution}, url={http://espace.inrs.ca/id/eprint/6599}, booktitle={Proceedings of the 2nd International Conference on Tomography of Materials and Structures}, publisher={International Association of Computed Tomography, Institut national de la recherche scientifique}, author={Périard, Y. and Gumiere, S.J. and Rousseau, A.N. and Hallema, D.W. and Caron, J.}, editor={Long, B.Editor}, year={2015}, month={Jun}, pages={632–636} }
 @article{lafond_gumiere_hallema_périard_jutras_caron_2015, title={Spatial Distribution Patterns of Soil Water Availability as a Tool for Precision Irrigation Management in Histosols: Characterization and Spatial Interpolation}, volume={14}, ISSN={1539-1663}, url={http://dx.doi.org/10.2136/vzj2014.10.0140}, DOI={10.2136/vzj2014.10.0140}, abstractNote={Lettuce (Lactuca sativa L.) production in organic soils is important in Quebec, Canada. Lettuce is highly sensitive to tip burn, a physiological disorder that can lead to significant yield losses. Tip burn losses have been linked to various factors, such as root water uptake deficits. A precision irrigation approach using local applications of water based on lettuce requirements and soil water available capacity (SWAC) reduces the occurrence of tip burn but may need mapped spatial information of SWAC for proper irrigation management. The objectives of this study were (i) to determine a rapid, efficient, and reliable method for interpolating SWAC and (ii) to use this interpolation method in precision irrigation simulations in management zones to demonstrate the importance of using SWAC maps. The methods for SWAC interpolation used in this study were inverse distance weighting (IDW), thin plate splines (TPS) and kriging with external drift (KED). The simulation used a calculation procedure for mass balance that contained SWAC maps, evapotranspiration (ET) and precipitation. A comparison of each interpolation method and multiple statistical criteria revealed that IDW and KED were the most precise methods, depending on the study site. Simulations of precision irrigation showed that in many cases, local irrigation management in seven to eight zones must account for the spatial distribution of SWAC to attain an 80% irrigation adequacy for lettuce. Hence, using SWAC maps as a tool for managing irrigation would allow growers to save water and to apply an accurate amount of water in appropriate areas.}, number={6}, journal={Vadose Zone Journal}, publisher={Wiley}, author={Lafond, Jonathan A. and Gumiere, Silvio J. and Hallema, Dennis W. and Périard, Yann and Jutras, Sylvain and Caron, Jean}, year={2015}, month={Mar}, pages={1–13} }
 @inproceedings{hallema_périard_lafond_gumiere_caron_2014, place={Sacramento, California}, title={Detection of drainage failure in reconstructed cranberry soils using time series analysis}, url={https://www.ispag.org/proceedings/?action=download&item=1505}, booktitle={Proceedings of the 12th International Conference on Precision Agriculture}, publisher={International Society of Precision Agriculture}, author={Hallema, D.W. and Périard, Y. and Lafond, J.A. and Gumiere, S.J. and Caron, J.}, editor={Shaver, T.M.Editor}, year={2014}, month={Jul}, pages={15} }
 @article{hallema_rousseau_gumiere_périard_hiemstra_bouttier_fossey_paquette_cogliastro_olivier_2014, title={Framework for studying the hydrological impact of climate change in an alley cropping system}, volume={517}, ISSN={0022-1694}, url={http://dx.doi.org/10.1016/j.jhydrol.2014.05.065}, DOI={10.1016/j.jhydrol.2014.05.065}, abstractNote={Summary Alley cropping is an agroforestry practice whereby crops are grown between hedgerows of trees planted at wide spacings. The local climate and the physiological adaptation mechanisms of the trees are key factors in the growth and survival of the trees and intercrops, because they directly affect the soil moisture distribution. In order to evaluate the long-term hydrological impact of climate change in an alley cropping system in eastern Canada, we developed a framework that combines local soil moisture data with local projections of climate change and a model of soil water movement, root uptake and evapotranspiration. Forty-five frequency domain reflectometers (FDR) along a transect perpendicular to the tree rows generated a two-year dataset that we used for the parameterization and evaluation of the model. An impact study with simulations based on local projections of three global and one regional climate simulation suggest that the soil becomes drier overall in the period between 2041 and 2070, while the number of critically wet periods with a length of one day increases slightly with respect to the reference period between 1967 and 1996. Hydrological simulations based on a fourth climate scenario however point toward wetter conditions. In all cases the changes are minor. Although our simulations indicate that the experimental alley cropping system will possibly suffer drier conditions in response to higher temperatures and increased evaporative demand, these conditions are not necessarily critical for vegetation during the snow-free season.}, journal={Journal of Hydrology}, publisher={Elsevier BV}, author={Hallema, Dennis W. and Rousseau, Alain N. and Gumiere, Silvio J. and Périard, Yann and Hiemstra, Paul H. and Bouttier, Léa and Fossey, Maxime and Paquette, Alain and Cogliastro, Alain and Olivier, Alain}, year={2014}, month={Sep}, pages={547–556} }
 @article{gumiere_lafond_hallema_périard_caron_gallichand_2014, title={Mapping soil hydraulic conductivity and matric potential for water management of cranberry: Characterisation and spatial interpolation methods}, volume={128}, ISSN={1537-5110}, url={http://dx.doi.org/10.1016/j.biosystemseng.2014.09.002}, DOI={10.1016/j.biosystemseng.2014.09.002}, abstractNote={Spatial interpolation methods are required for analysing the effects of soil hydraulic properties on irrigation management. This study was conducted to determine which interpolation methods are best suited to map these properties. During the summer of 2012 we mapped the spatial variability of soil physical properties, soil matric potential, water table depth and yield of two cranberry fields located near Quebec City, Canada. Three spatial interpolation methods, inverse distance weighting (IDW), thin plate splines (TPS) and kriging with external drift (KED), were compared by means of cross-validation. The best interpolation method for a given property was used to produce maps and perform HYDRUS 1D simulations for the purpose of irrigation management. Results show that even in highly constructed fields, such as for cranberries, spatial patterns of soil hydraulic properties exist. The TPS method was the best interpolation method based on the cross-validation analyses and generated maps. Spatial variability of crop yield showed a strong relationship with soil hydraulic properties and simulations suggest that irrigation can be reduced by 75% when accounting for the spatial variability of soil hydraulic properties.}, journal={Biosystems Engineering}, publisher={Elsevier BV}, author={Gumiere, Silvio J. and Lafond, Jonathan A. and Hallema, Dennis W. and Périard, Yann and Caron, Jean and Gallichand, Jacques}, year={2014}, month={Dec}, pages={29–40} }
 @article{hallema_moussa_2013, title={A model for distributed GIUH-based flow routing on natural and anthropogenic hillslopes}, volume={28}, ISSN={0885-6087}, url={http://dx.doi.org/10.1002/hyp.9984}, DOI={10.1002/hyp.9984}, abstractNote={Attempts to reduce the number of parameters in distributed rainfall–runoff models have not yet resulted in a model that is accurate for both natural and anthropogenic hillslopes. We take on the challenge by proposing a distributed model for overland flow and channel flow based on a combination of a linear response time distribution and the hillslope geomorphologic instantaneous unit hydrograph (GIUH), which can be calculated with only a digital elevation model and a map with field boundaries and channel network as input. The spatial domain is subdivided into representative elementary hillslopes (REHs) for each of which we define geometric and flow velocity parameters and compute the GIUH. The catchment GIUH is given by the sum of all REH responses. While most distributed models only perform well on natural hillslopes, the advantage of our approach is that it can also be applied to modified hillslopes with for example a rectangular drainage network and terrace cultivation. Tests show that the REH‐GIUH approach performs better than classical routing functions (exponential and gamma). Simulations of four virtual hillslopes suggest that peak flow at the catchment outlet is directly related to drainage density. By combining the distributed flow routing model with a lumped‐parameter infiltration model, we were also able to demonstrate that terrace cultivation delays the response time and reduces peak flow in comparison to the same hillslope, but with a natural stream network. The REH‐GIUH approach is a first step in the process of coupling distributed hydrological models to erosion and water quality models at the REH (associated with agricultural management) and at the catchment scale (associated with the evaluation of the environmental impact of human activities). It furthermore provides a basis for the development of models for large catchments and urban or peri‐urban catchments. Copyright © 2013 John Wiley & Sons, Ltd.}, number={18}, journal={Hydrological Processes}, publisher={Wiley}, author={Hallema, Dennis W. and Moussa, Roger}, year={2013}, month={Aug}, pages={4877–4895} }
 @book{olivier_paquette_cogliastro_rousseau_messier_revéret_rivest_gumiere_hallema_hould-gosselin_et al._2013, place={Université Laval, Quebec City, Canada}, title={Contribution de systèmes agroforestiers multifonctionnels à la capacité d’adaptation aux changements climatiques des agro-écosystèmes}, url={https://www.ouranos.ca/publication-scientifique/RapportOlivier2013_FR.pdf}, number={550412-111}, author={Olivier, A. and Paquette, A. and Cogliastro, A. and Rousseau, A. and Messier, C. and Revéret, J.-P. and Rivest, D. and Gumiere, S.J. and Hallema, D.W. and Hould-Gosselin, G. and et al.}, year={2013} }
 @article{gumiere_rousseau_hallema_isabelle_2013, title={Development of VFDM: a riparian vegetated filter dimensioning model for agricultural watersheds}, volume={38}, ISSN={0701-1784 1918-1817}, url={http://dx.doi.org/10.1080/07011784.2013.830372}, DOI={10.1080/07011784.2013.830372}, abstractNote={Dimensioning and positioning structural beneficial management practices (BMPs) represent a “real life” challenge for soil conservation engineers, managers, planners and policy-makers. Different factors, such as trapping efficiency; implementation, management, and opportunity costs (resulting from cropland loss), and government policies and guidelines need to be weighed to meet this challenge. The trapping efficiency of structural BMPs may depend on many parameters, including: (1) characteristics of vegetated filters (VF) such as width and slope, vegetation height, vegetation density and species composition, (2) flow characteristics such as runoff velocity, discharge volume and water height, and (3) sediment characteristics such as particle size, aggregation and concentration. Government policies and guidelines may include dimension and location of VFs and/or a cropland percentage that needs to be converted into VF areas. The main objectives of this paper are to: (1) describe the development of the Vegetated Filter Dimensioning Model (VFDM), a mathematical model to determine the optimal dimensions of riparian vegetated filter strips (RVFSs) in agricultural watersheds, and (2) illustrate the potential use of the model on a pilot watershed, the Beaurivage watershed, in Quebec, Canada. The latter was done for the sole purpose of model testing with readily available input parameters and data. The model calculates the optimal width with respect to vegetation, topographical, hydrological and sedimentological characteristics. The results of this case study showed that the average recommended RVFS for the Beaurivage River watershed is about 3 m wide. Le dimensionnement et le positionnement de bandes riveraines (BR) représentent un défi important pour les ingénieurs, gestionnaires, planificateurs et les représentants politiques qui décident des régulations dans ce domaine. Plusieurs facteurs, tel que l’efficacité de captation des sédiments; l’implémentation, la gestion et les coûts d’opportunité (résultant de la perte de terres agricoles), et les politiques et régulations gouvernementales doivent être pris en compte pour relever ce défi. L’efficacité de captation dépend de plusieurs paramètres, incluant (1) les caractéristiques de la BR, tel que sa largeur et sa pente, la hauteur de la végétation, la densité de végétation et les espèces en présence; (2) les caractéristiques de l’écoulement, tel que la vitesse de ruissellement, le volume d’écoulement et la hauteur d’eau, et (3) les caractéristiques des sédiments, tel que la taille des particules, leur agrégation et leur concentration. Les politiques et régulations gouvernementales peuvent inclure la dimension et l’emplacement des BR et/ou un pourcentage de terres agricoles devant être converties en BR. Les objectifs principaux de cet article sont : (1) décrire le développement de VFDM (Vegetated Filter Dimensioning Model), un modèle mathématique pour déterminer les dimensions optimales des bandes riveraines dans des bassins versants agricoles, et (2) illustrer l’utilisation potentielle du modèle sur un bassin versant pilote, le bassin de la rivière Beaurivage, Québec, Canada. Ce dernier objectif a été fait dans le but de tester le modèle avec des paramètres et données d’entrées déjà disponibles. Le modèle calcule la largeur optimale en fonction des caractéristiques topographiques, hydrologiques, sédimentologiques et de la végétation. Les résultats de cette étude indiquent que les largeurs des bandes riveraines dans le bassin de la rivière Beaurivage devraient être de l’ordre de 3 m.}, number={3}, journal={Canadian Water Resources Journal}, publisher={Informa UK Limited}, author={Gumiere, Silvio J. and Rousseau, Alain N. and Hallema, Dennis W. and Isabelle, Pierre-Erik}, year={2013}, month={Sep}, pages={169–184} }
 @article{rousseau_savary_hallema_gumiere_foulon_2013, title={Modeling the effects of agricultural BMPs on sediments, nutrients, and water quality of the Beaurivage River watershed (Quebec, Canada)}, volume={38}, ISSN={0701-1784 1918-1817}, url={http://dx.doi.org/10.1080/07011784.2013.780792}, DOI={10.1080/07011784.2013.780792}, abstractNote={Agriculture has evolved into the largest non-point source of surface water pollution in Canada as a result of intensification over the past forty years. The Canadian WEBs project (Watershed Evaluation of Beneficial Management Practices, BMPs) was launched to evaluate the environmental and economic performance of BMPs as a means to mitigate agricultural sediment and nutrient issues. In this paper, the Gestion Intégrée des Bassins versant à l’aide d’un Système Informatisé (GIBSI) (or Integrated Watershed Management using a Computer System) integrated modeling framework was used to evaluate the effects of different BMPs on sediment and nutrient yields, as well as water quality in the Beaurivage River watershed in the province of Quebec. A reference scenario was developed that describes the current situation (i.e., base case scenario) of the watershed by calibrating the models used within GIBSI, namely HYDROTEL for hydrology, the Revised Universal Soil Loss Equation (RUSLE) for soil erosion, the Erosion-the Productivity Impact Calculator (EPIC) of the Soil and Water Assessment Tool (SWAT) for contaminant transport and fate, and QUAL2E for stream water quality. The effects of four BMPs were studied: (1) vegetated riparian buffer strips, (2) precision slurry application, (3) grassland conversion of cereal and corn fields, and (4) no-till (on corn fields). Simulation results indicate that BMPs can be effective in reducing nutrient and suspended sediment loads in both surface runoff and stream flow. More specifically, buffer strip and crop rotation showed better efficiency than hog-slurry management and no-till on corn BMPs. Moreover, results highlight the need for further investigation of sediment dynamics in the stream network as well as in the riparian buffer strips.}, number={2}, journal={Canadian Water Resources Journal}, publisher={Informa UK Limited}, author={Rousseau, Alain N. and Savary, Stéphane and Hallema, Dennis W. and Gumiere, Silvio J. and Foulon, Étienne}, year={2013}, month={Jun}, pages={99–120} }
 @book{hallema_rousseau_paquette_gumiere_2013, place={Quebec City, Canada}, title={The effects of Hurricane Sandy measured in the Laurentian foothills of Quebec (Canada) with a mobile weather station}, url={http://espace.inrs.ca/id/eprint/1663}, number={1349}, institution={Institut national de la recherche scientifique}, author={Hallema, D.W. and Rousseau, A.N. and Paquette, A. and Gumiere, S.J.}, year={2013} }
 @book{rousseau_hallema_gumiere_hould-gosselin_ratté-fortin_2013, place={Quebec City, Canada}, title={The influence of alley cropping systems on soil water dynamics and soil erosion in a changing climate}, url={http://espace.inrs.ca/2776/1/R001441.pdf}, number={R-1441}, institution={Centre Eau Terre Environnement, Institut national de la recherche scientifique}, author={Rousseau, A.N. and Hallema, D.W. and Gumiere, S.J. and Hould-Gosselin, G. and Ratté-Fortin, C.}, year={2013} }
 @article{hallema_moussa_andrieux_voltz_2012, title={Parameterization and multi-criteria calibration of a distributed storm flow model applied to a Mediterranean agricultural catchment}, volume={27}, ISSN={0885-6087}, url={http://dx.doi.org/10.1002/hyp.9268}, DOI={10.1002/hyp.9268}, abstractNote={Abstract}, number={10}, journal={Hydrological Processes}, publisher={Wiley}, author={Hallema, Dennis W. and Moussa, Roger and Andrieux, Patrick and Voltz, Marc}, year={2012}, month={Apr}, pages={1379–1398} }
 @book{rousseau_hallema_gumiere_carrer_fossey_2012, place={Quebec City, Canada}, title={The influence of alley cropping systems on soil water dynamics and soil erosion in a changing climate}, url={http://espace.inrs.ca/id/eprint/1200}, number={R-1334}, institution={Institut national de la recherche scientifique}, author={Rousseau, A.N. and Hallema, D.W. and Gumiere, S.J. and Carrer, G. and Fossey, M.}, year={2012} }