@article{caldwell_martin_vose_baker_warziniack_costanza_frey_nehra_mihiar_2023, title={Forested watersheds provide the highest water quality among all land cover types, but the benefit of this ecosystem service depends on landscape context}, volume={882}, ISSN={["1879-1026"]}, DOI={10.1016/j.scitotenv.2023.163550}, abstractNote={Conversion of natural land cover can degrade water quality in water supply watersheds and increase treatment costs for Public Water Systems (PWSs), but there are few studies that have fully evaluated land cover and water quality relationships in mixed use watersheds across broad hydroclimatic settings. We related upstream land cover (forest, other natural land covers, development, and agriculture) to observed and modeled water quality across the southeastern US and specifically at 1746 PWS drinking water intake facilities. While there was considerable complexity and variability in the relationship between land cover and water quality, results suggest that Total Nitrogen (TN), Total Phosphorus (TP) and Suspended Sediment (SS) concentrations decrease significantly with increasing forest cover, and increase with increasing developed or agricultural cover. Catchments with dominant (>90 %) agricultural land cover had the greatest export rates for TN, TP, and SS based on SPARROW model estimates, followed by developed-dominant, then forest- and other-natural-dominant catchments. Variability in modeled TN, TP, and SS export rates by land cover type was driven by variability in natural background sources and catchment characteristics that affected water quality even in forest-dominated catchments. Both intake setting (i.e., run-of-river or reservoir) and upstream land cover were important determinants of water quality at PWS intakes. Of all PWS intakes, 15 % had high raw water quality, and 85 % of those were on reservoirs. Of the run-of-river intakes with high raw water quality, 75 % had at least 50 % forest land cover upstream. In addition, PWS intakes obtaining surface water supply from smaller upstream catchments may experience the largest losses of natural land cover based on projections of land cover in 2070. These results illustrate the complexity and variability in the relationship between land cover and water quality at broad scales, but also suggest that forest conservation can enhance the resilience of drinking water supplies.}, journal={SCIENCE OF THE TOTAL ENVIRONMENT}, author={Caldwell, Peter V. and Martin, Katherine L. and Vose, James M. and Baker, Justin S. and Warziniack, Travis W. and Costanza, Jennifer K. and Frey, Gregory E. and Nehra, Arpita and Mihiar, Christopher M.}, year={2023}, month={Jul} }
 @article{amatya_tian_marion_caldwell_laseter_youssef_grace_chescheir_panda_ouyang_et al._2021, title={Estimates of Precipitation IDF Curves and Design Discharges for Road-Crossing Drainage Structures: Case Study in Four Small Forested Watersheds in the Southeastern US}, volume={26}, ISSN={["1943-5584"]}, DOI={10.1061/(ASCE)HE.1943-5584.0002052}, abstractNote={AbstractWe compared precipitation intensity-duration-frequency (PIDF) curves developed for four small forested watersheds to spatially interpolated estimates from the National Oceanic and Atmospher...}, number={4}, journal={JOURNAL OF HYDROLOGIC ENGINEERING}, author={Amatya, D. M. and Tian, S. and Marion, D. A. and Caldwell, P. and Laseter, S. and Youssef, M. A. and Grace, J. M. and Chescheir, G. M. and Panda, S. and Ouyang, Y. and et al.}, year={2021}, month={Apr} }
 @article{neville_emanuel_nichols_vose_2021, title={Extreme Flooding and Nitrogen Dynamics of a Blackwater River}, volume={57}, ISSN={["1944-7973"]}, url={http://dx.doi.org/10.1029/2020wr029106}, DOI={10.1029/2020WR029106}, abstractNote={Extreme floods, including those expected to become more frequent in a warming world, may impact nutrient metabolism in streams. However, flood impacts on spatial and temporal variability of nutrient dynamics on large rivers (e.g., fourth order and higher) have been understudied. In 2016, Hurricane Matthew provided a unique opportunity to evaluate nitrate retention and processing on the Lumbee River, a blackwater stream in southeastern North Carolina. The 3,000+ km2 watershed received as much as 400 mm of rain in 48 hr as the storm moved across the Atlantic Coastal Plain. Resulting floods in the watershed were the largest on record, based on more than 80 years of continuous streamflow measurements at the watershed outlet. We used a modified Lagrangian sampling method to collect water samples and supporting water quality data at multiple points along three reaches of the Lumbee River for several months before and after Hurricane Matthew. Samples were analyzed for nitrate‐nitrogen and used to estimate retention and areal uptake rates for multiple subsections within each reach. Although nitrate‐nitrogen concentrations did not change significantly after the flood, we found that the spatial variability of within‐reach retention and areal uptake increased substantially following the flood, evidenced by changes to within‐reach interquartile ranges. The spatial variability of areal uptake returned to pre‐flood levels approximately eight months after Hurricane Matthew, but retention variability remained elevated at the end of our field study. These results highlight the potential for extreme flooding to impact biogeochemical processes in large rivers long after flood waters subside.}, number={12}, journal={WATER RESOURCES RESEARCH}, publisher={American Geophysical Union (AGU)}, author={Neville, J. A. and Emanuel, R. E. and Nichols, E. G. and Vose, J.}, year={2021}, month={Dec} }
 @article{qiu_song_zhang_liu_vose_2020, title={Urbanization and climate change jointly shift land surface phenology in the northern mid-latitude large cities}, volume={236}, ISSN={["1879-0704"]}, DOI={10.1016/j.rse.2019.111477}, abstractNote={Land surface phenology (LSP) has been widely used as the “footprint” of urbanization and global climate change. Shifts of LSP have cascading effects on food production, carbon sequestration, water consumption, biodiversity, and public health. Previous studies mainly focused on investigating the effects of urbanization on the spatial patterns of LSP by comparing phenological metrics, e.g. start of season (SOS) and end of season (EOS), between urban center and the surrounding rural regions. However, it remains unclear how urbanization-induced land cover conversions and climate change jointly influence the temporal variations of SOS and EOS within the urban ecosystem. To fill this knowledge gap, we utilized daily two-band enhanced vegetation index, daily meteorological record, and annual land cover dataset to investigate the respective impacts of urbanization and climate change on temporal shifts of LSP between the post- and the pre-urbanization periods over 196 large cities in the northern mid-latitudes. We found 51% of the cities experienced an advanced SOS with an average of −6.39 ± 5.82 days after urbanization has occurred, while the remaining 49% of the cities had a delayed SOS with an average of 7.56 ± 5.63 days. We also found a later EOS at 53% of the cities and an earlier EOS at 47% of the cities with an average of 8.43 ± 7.59 and −5.57 ± 4.99 days between the post- and pre-urbanization periods, respectively. Multiple linear regression analysis indicates that climate variables (i.e. temperature, precipitation, and insolation) play dominant roles in regulating the temporal shifts of LSP. Furthermore, the earlier SOS and later EOS were significantly correlated with the amplitude of urbanization (i.e. increase of impervious surface area) in cities after controlling for effects of climate factors. These patterns were generally consistent across eight climate zones. Our findings provide critical information in modeling natural and anthropogenic effects on urban ecosystem, with important benefits for urban sustainability and biodiversity conservation.}, journal={REMOTE SENSING OF ENVIRONMENT}, author={Qiu, Tong and Song, Conghe and Zhang, Yulong and Liu, Hongsheng and Vose, James M.}, year={2020}, month={Jan} }
 @article{suttles_singh_vose_martin_emanuel_coulston_saia_crump_2018, title={Assessment of hydrologic vulnerability to urbanization and climate change in a rapidly changing watershed in the Southeast US}, volume={645}, ISSN={["1879-1026"]}, url={http://dx.doi.org/10.1016/j.scitotenv.2018.06.287}, DOI={10.1016/j.scitotenv.2018.06.287}, abstractNote={This study assessed the combined effects of increased urbanization and climate change on streamflow in the Yadkin-Pee Dee watershed (North Carolina, USA) and focused on the conversion from forest to urban land use, the primary land use transition occurring in the watershed. We used the Soil and Water Assessment Tool to simulate future (2050-2070) streamflow and baseflow for four combined climate and land use scenarios across the Yadkin-Pee Dee River watershed and three subwatersheds. The combined scenarios pair land use change and climate change scenarios together. Compared to the baseline, projected streamflow increased in three out of four combined scenarios and decreased in one combined scenario. Baseflow decreased in all combined scenarios, but decreases were largest in subwatersheds that lost the most forest. The effects of land use change and climate change were additive, amplifying the increases in runoff and decreases in baseflow. Streamflow was influenced more strongly by climate change than land use change. However, for baseflow the reverse was true; land use change tended to drive baseflow more than climate change. Land use change was also a stronger driver than climate in the most urban subwatershed. In the most extreme land use and climate projection the volume of the 1-day, 100 year flood nearly doubled at the watershed outlet. Our results underscore the importance of forests as hydrologic regulators buffering streamflow and baseflow from hydrologic extremes. Additionally, our results suggest that land managers and policy makers need to consider the implications of forest loss on streamflow and baseflow when planning for future urbanization and climate change adaptation options.}, journal={SCIENCE OF THE TOTAL ENVIRONMENT}, author={Suttles, Kelly M. and Singh, Nitin K. and Vose, James M. and Martin, Katherine L. and Emanuel, Ryan E. and Coulston, John W. and Saia, Sheila M. and Crump, Michael T.}, year={2018}, month={Dec}, pages={806–816} }
 @article{hwang_martin_vose_wear_miles_kim_band_2018, title={Nonstationary Hydrologic Behavior in Forested Watersheds Is Mediated by Climate‐Induced Changes in Growing Season Length and Subsequent Vegetation Growth}, volume={54}, ISSN={0043-1397 1944-7973}, url={http://dx.doi.org/10.1029/2017WR022279}, DOI={10.1029/2017WR022279}, abstractNote={Forested watersheds provide important ecosystem services through the provision of high quality freshwater, mitigation of floods, and maintenance of base flows. How alteration of these services under ongoing climate change is mediated by vegetation dynamics is not fully understood. Combining independent remote sensing based vegetation information and distributed hydrological modeling, we investigated the impact of climate‐induced vegetation dynamics on long‐term non‐stationary hydrologic behavior in two forested watersheds in the southern Appalachians. We found significant increases in precipitation‐runoff deficit (defined as annual precipitation minus annual runoff), equivalent to annual evapotranspiration plus storage changes, over the last three decades. This non‐stationary hydrologic behavior was significantly correlated with long‐term and interannual changes in growing season length and subsequent vegetation growth. These patterns in vegetation phenology were attributed primarily to minimum temperature regimes, which showed steeper and more consistent increases than temperature maxima. Using a distributed modeling framework, we also found that the long‐term non‐stationary hydrologic behavior could not be simulated unless full vegetation dynamics, including vegetation phenology and long‐term growth, were incorporated into the model. Incorporating seasonal vegetation dynamics also led to the improved simulation in streamflow dynamics, while its effect spread out through the following dormant seasons. Our study indicates that non‐stationary hydrologic behavior has been closely mediated by long‐term seasonal and structural forest canopy interaction with climate variables rather than directly driven by climatic variables. This study emphasizes the importance of understanding the ecosystem responses to ongoing climate change for predictions of future freshwater regimes.}, number={8}, journal={Water Resources Research}, publisher={American Geophysical Union (AGU)}, author={Hwang, Taehee and Martin, Katherine L. and Vose, James M. and Wear, David and Miles, Brian and Kim, Yuri and Band, Lawrence E.}, year={2018}, month={Aug}, pages={5359–5375} }
 @article{knoepp_see_vose_miniat_clark_2018, title={Total C and N Pools and Fluxes Vary with Time, Soil Temperature, and Moisture Along an Elevation, Precipitation, and Vegetation Gradient in Southern Appalachian Forests}, volume={21}, ISSN={["1435-0629"]}, DOI={10.1007/s10021-018-0244-2}, number={8}, journal={ECOSYSTEMS}, author={Knoepp, Jennifer D. and See, Craig R. and Vose, James M. and Miniat, Chelcy F. and Clark, James S.}, year={2018}, month={Dec}, pages={1623–1638} }
 @article{oishi_miniat_novick_brantle_vose_walker_2018, title={Warmer temperatures reduce net carbon uptake, but do not affect water use, in a mature southern Appalachian forest}, volume={252}, ISSN={["1873-2240"]}, DOI={10.1016/j.agrformet.2018.01.011}, abstractNote={Increasing air temperature is expected to extend growing season length in temperate, broadleaf forests, leading to potential increases in evapotranspiration and net carbon uptake. However, other key processes affecting water and carbon cycles are also highly temperature-dependent. Warmer temperatures may result in higher ecosystem carbon loss through respiration and higher potential evapotranspiration through increased atmospheric demand for water. Thus, the net effects of a warming planet are uncertain and highly dependent on local climate and vegetation. We analyzed five years of data from the Coweeta eddy covariance tower in the southern Appalachian Mountains of western North Carolina, USA, a highly productive region that has historically been underrepresented in flux observation networks. We examined how leaf phenology and climate affect water and carbon cycling in a mature forest in one of the wettest biomes in North America. Warm temperatures in early 2012 caused leaf-out to occur two weeks earlier than in cooler years and led to higher seasonal carbon uptake. However, these warmer temperatures also drove higher winter ecosystem respiration, offsetting much of the springtime carbon gain. Interannual variability in net carbon uptake was high (147 to 364 g C m−2 y−1), but unrelated to growing season length. Instead, years with warmer growing seasons had 10% higher respiration and sequestered ∼40% less carbon than cooler years. In contrast, annual evapotranspiration was relatively consistent among years (coefficient of variation = 4%) despite large differences in precipitation (17%, range = 800 mm). Transpiration by the evergreen understory likely helped to compensate for phenologically-driven differences in canopy transpiration. The increasing frequency of high summer temperatures is expected to have a greater effect on respiration than growing season length, reducing forest carbon storage.}, journal={AGRICULTURAL AND FOREST METEOROLOGY}, author={Oishi, A. Christopher and Miniat, Chelcy F. and Novick, Kimberly A. and Brantle, Steven T. and Vose, James M. and Walker, John T.}, year={2018}, month={Apr}, pages={269–282} }
 @misc{golladay_martin_vose_wear_covich_hobbs_klepzig_likens_naiman_shearer_et al._2016, title={Achievable future conditions as a framework for guiding forest conservation and management}, volume={360}, ISSN={["1872-7042"]}, DOI={10.1016/j.foreco.2015.10.009}, abstractNote={We contend that traditional approaches to forest conservation and management will be inadequate given the predicted scale of social-economic and biophysical changes in the 21st century. New approaches, focused on anticipating and guiding ecological responses to change, are urgently needed to ensure the full value of forest ecosystem services for future generations. These approaches acknowledge that change is inevitable and sometimes irreversible, and that maintenance of ecosystem services depends in part on novel ecosystems, i.e., species combinations with no analog in the past. We propose that ecological responses be evaluated at landscape or regional scales using risk-based approaches to incorporate uncertainty into forest management efforts with subsequent goals for management based on Achievable Future Conditions (AFC). AFCs defined at a landscape or regional scale incorporate advancements in ecosystem management, including adaptive approaches, resilience, and desired future conditions into the context of the Anthropocene. Inherently forward looking, ACFs encompass mitigation and adaptation options to respond to scenarios of projected future biophysical, social-economic, and policy conditions which distribute risk and provide diversity of response to uncertainty. The engagement of science-management-public partnerships is critical to our risk-based approach for defining AFCs. Robust monitoring programs of forest management actions are also crucial to address uncertainty regarding species distributions and ecosystem processes. Development of regional indicators of response will also be essential to evaluate outcomes of management strategies. Our conceptual framework provides a starting point to move toward AFCs for forest management, illustrated with examples from fire and water management in the Southeastern United States. Our model is adaptive, incorporating evaluation and modification as new information becomes available and as social–ecological dynamics change. It expands on established principles of ecosystem management and best management practices (BMPs) and incorporates scenarios of future conditions. It also highlights the potential limits of existing institutional structures for defining AFCs and achieving them. In an uncertain future of rapid change and abrupt, unforeseen transitions, adjustments in management approaches will be necessary and some actions will fail. However, it is increasingly evident that the greatest risk is posed by continuing to implement strategies inconsistent with current understanding of our novel future.}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Golladay, S. W. and Martin, K. L. and Vose, J. M. and Wear, D. N. and Covich, A. P. and Hobbs, R. J. and Klepzig, K. D. and Likens, G. E. and Naiman, R. J. and Shearer, A. W. and et al.}, year={2016}, month={Jan}, pages={80–96} }
 @article{vose_martin_barten_2016, title={Applications of forest hydrological science to watershed management in the 21st century}, DOI={10.1079/9781780646602.0240}, abstractNote={This chapter examines the role of forest hydrological science in the development and application of watershed management in the 21st century. It provides a brief synthesis of anticipated biophysical and socioeconomic changes expected to occur over the coming decades and discuss critical watershed science needs and management responses to maintain watershed ecosystem services in the coming decades. The chapter builds on several recent discussions on the role of ecohydrology in addressing water resource challenges now and in the future. The examples focus on forest watersheds in the southern US forests, as the complex mixture of public and private forest land ownership creates substantial challenges for watershed management at larger spatial scales. Despite the focus on the southern USA, the general principles are applicable to forest watersheds across the globe.}, journal={Forest Hydrology: Processes, Management and Assessment}, author={Vose, J. M. and Martin, Katherine and Barten, P. K.}, year={2016}, pages={240–253} }
 @article{novick_miniat_vose_2016, title={Drought limitations to leaf-level gas exchange: results from a model linking stomatal optimization and cohesion-tension theory}, volume={39}, ISSN={["1365-3040"]}, DOI={10.1111/pce.12657}, abstractNote={We merge concepts from stomatal optimization theory and cohesion-tension theory to examine the dynamics of three mechanisms that are potentially limiting to leaf-level gas exchange in trees during drought: (1) a 'demand limitation' driven by an assumption of optimal stomatal functioning; (2) 'hydraulic limitation' of water movement from the roots to the leaves; and (3) 'non-stomatal' limitations imposed by declining leaf water status within the leaf. Model results suggest that species-specific 'economics' of stomatal behaviour may play an important role in differentiating species along the continuum of isohydric to anisohydric behaviour; specifically, we show that non-stomatal and demand limitations may reduce stomatal conductance and increase leaf water potential, promoting wide safety margins characteristic of isohydric species. We used model results to develop a diagnostic framework to identify the most likely limiting mechanism to stomatal functioning during drought and showed that many of those features were commonly observed in field observations of tree water use dynamics. Direct comparisons of modelled and measured stomatal conductance further indicated that non-stomatal and demand limitations reproduced observed patterns of tree water use well for an isohydric species but that a hydraulic limitation likely applies in the case of an anisohydric species.}, number={3}, journal={PLANT CELL AND ENVIRONMENT}, author={Novick, Kimberly A. and Miniat, Chelcy F. and Vose, James M.}, year={2016}, month={Mar}, pages={583–596} }
 @misc{schlesinger_dietze_jackson_phillips_rhoades_rustad_vose_2016, title={Forest biogeochemistry in response to drought}, volume={22}, ISSN={["1365-2486"]}, DOI={10.1111/gcb.13105}, abstractNote={Trees alter their use and allocation of nutrients in response to drought, and changes in soil nutrient cycling and trace gas flux (N2O and CH4) are observed when experimental drought is imposed on forests. In extreme droughts, trees are increasingly susceptible to attack by pests and pathogens, which can lead to major changes in nutrient flux to the soil. Extreme droughts often lead to more common and more intense forest fires, causing dramatic changes in the nutrient storage and loss from forest ecosystems. Changes in the future manifestation of drought will affect carbon uptake and storage in forests, leading to feedbacks to the Earth's climate system. We must improve the recognition of drought in nature, our ability to manage our forests in the face of drought, and the parameterization of drought in earth system models for improved predictions of carbon uptake and storage in the world's forests.}, number={7}, journal={GLOBAL CHANGE BIOLOGY}, author={Schlesinger, William H. and Dietze, Michael C. and Jackson, Robert B. and Phillips, Richard P. and Rhoades, Charles C. and Rustad, Lindsey E. and Vose, James M.}, year={2016}, month={Jul}, pages={2318–2328} }
 @article{vose_elliott_2016, title={OAK, FIRE, AND GLOBAL CHANGE IN THE EASTERN USA: WHAT MIGHT THE FUTURE HOLD?}, volume={12}, ISSN={["1933-9747"]}, DOI={10.4996/fireecology.1202160}, abstractNote={The pace of environmental and socioeconomic change over the past 100 years has been rapid. Changes in fire regimes, climate, and land use have shaped the structure and function of most forest ecosystems, including oak (Quercus spp. L.) forests in the eastern United States. New stressors such as air pollution and invasive species have contributed to and interacted with climate and fire to alter current forest conditions. While changing fire regimes have altered species composition of the current forest, oak regeneration is constrained by many factors that may affect future forests. Over the remainder of the twenty-first century, an accelerating pace of climate and socioeconomic changes will influence the future range of variation in Eastern oak forests. Some of these impacts will be direct, such as changes in tree growth rates, while other impacts will be indirect, such as new disturbance regimes. While it is likely that fire will be important in shaping oak forests in the twenty-first century, it is less clear exactly what that role will be. For example, it is uncertain whether our current scientific knowledge on the use of prescribed fire in oak forests will be applicable under novel climate and changing socioeconomic conditions. We propose that the combination of climate change, wildfire, and other disturbances will create stand conditions that favor oaks with or without management. However, management intervention (e.g., prescribed fire, thinning, or a combination) could reduce wildfire hazard, particularly in the wildland-urban interface, and create more desirable stand conditions that are resilient to future stressors such as changing precipitation patterns and warmer temperatures.ResumenEl ritmo de los cambios ambientales y socioeconómicos en los últimos 100 años ha sido rápido. Cambios en los regímenes de fuego, en el clima y en el uso de la tierra han modelado la estructura y función de la mayoría de los ecosistemas boscosos incluyendo los bosques de roble (Quercus spp. L.) en el este de los EEUU. Nuevos agentes de estrés como la contaminación del aire y las especies invasoras han contribuido e interactuado con el clima y el fuego para alterar las condiciones actuales reinantes en el bosque. Mientras que el cambio en los regímenes de fuego han alterado la composición de especies en el bosque actual, la regeneración del roble está condicionada por varios factores que podrían afectar los bosques futuros. En lo que queda del siglo XXI, un ritmo acelerado de cambios climáticos y socioeconómicos influirán en el futuro rango de variación en los bosques orientales de roble. Algunos de estos impactos van a ser directos, como cambios en las tasas de crecimiento, mientras que otros impactos van a ser indirectos como nuevos regímenes de disturbios. Si bien es muy probable que el fuego sea un importante modelador de los bosques de roble en el siglo XXI, no está tan claro cuál será su rol. Por ejemplo, es incierto si nuestro conocimiento científico actual sobre el uso de quemas prescriptas será aplicable bajo las nuevas condiciones climáticas y los cambios socioeconómicos. Nosotros proponemos que la combinación del cambio climático, los incendios y otros disturbios crearán condiciones en el rodal que van a favorecer los robles con o sin manejo. Sin embargo, las intervenciones en el manejo (por ej. quemas prescriptas, raleos o una combinación), podrían reducir el peligro de incendios, particularmente en la interfaz urbano-rural y crear condiciones deseables en el rodal que sean resilientes a futuros agentes de estrés como cambios en los patrones de precipitación y las altas temperaturas.}, number={2}, journal={FIRE ECOLOGY}, author={Vose, James M. and Elliott, Katherine J.}, year={2016}, pages={160–179} }
 @article{kelly_mcguire_miniat_vose_2016, title={Streamflow response to increasing precipitation extremes altered by forest management}, volume={43}, ISSN={["1944-8007"]}, DOI={10.1002/2016gl068058}, abstractNote={Increases in extreme precipitation events of floods and droughts are expected to occur worldwide. The increase in extreme events will result in changes in streamflow that are expected to affect water availability for human consumption and aquatic ecosystem function. We present an analysis that may greatly improve current streamflow models by quantifying the impact of the interaction between forest management and precipitation. We use daily long‐term data from paired watersheds that have undergone forest harvest or species conversion. We find that interactive effects of climate change, represented by changes in observed precipitation trends, and forest management regime, significantly alter expected streamflow most often during extreme events, ranging from a decrease of 59% to an increase of 40% in streamflow, depending upon management. Our results suggest that vegetation might be managed to compensate for hydrologic responses due to climate change to help mitigate effects of extreme changes in precipitation.}, number={8}, journal={GEOPHYSICAL RESEARCH LETTERS}, author={Kelly, Charlene N. and McGuire, Kevin J. and Miniat, Chelcy Ford and Vose, James M.}, year={2016}, month={Apr}, pages={3727–3736} }
 @article{rice_emanuel_vose_2016, title={The influence of watershed characteristics on spatial patterns of trends in annual scale streamflow variability in the continental US}, volume={540}, ISSN={["1879-2707"]}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000382269500066&KeyUID=WOS:000382269500066}, DOI={10.1016/j.jhydrol.2016.07.006}, abstractNote={As human activity and climate variability alter the movement of water through the environment the need to better understand hydrologic cycle responses to these changes has grown. A reasonable starting point for gaining such insight is studying changes in streamflow given the importance of streamflow as a source of renewable freshwater. Using a wavelet assisted method we analyzed trends in the magnitude of annual scale streamflow variability from 967 watersheds in the continental U.S. (CONUS) over a 70 year period (1940–2009). Decreased annual variability was the dominant pattern at the CONUS scale. Ecoregion scale results agreed with the CONUS pattern with the exception of two ecoregions closely divided between increases and decreases and one where increases dominated. A comparison of trends in reference and non-reference watersheds indicated that trend magnitudes in non-reference watersheds were significantly larger than those in reference watersheds. Boosted regression tree (BRT) models were used to study the relationship between watershed characteristics and the magnitude of trends in streamflow. At the CONUS scale, the balance between precipitation and evaporative demand, and measures of geographic location were of high relative importance. Relationships between the magnitude of trends and watershed characteristics at the ecoregion scale exhibited differences from the CONUS results and substantial variability was observed among ecoregions. Additionally, the methodology used here has the potential to serve as a robust framework for top-down, data driven analyses of the relationships between changes in the hydrologic cycle and the spatial context within which those changes occur.}, journal={JOURNAL OF HYDROLOGY}, author={Rice, Joshua S. and Emanuel, Ryan E. and Vose, James M.}, year={2016}, month={Sep}, pages={850–860} }
 @article{nippgen_mcglynn_emanuel_vose_2016, title={Watershed memory at the Coweeta Hydrologic Laboratory: The effect of past precipitation and storage on hydrologic response}, volume={52}, ISSN={["1944-7973"]}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000374706300007&KeyUID=WOS:000374706300007}, DOI={10.1002/2015wr018196}, abstractNote={The rainfall‐runoff response of watersheds is affected by the legacy of past hydroclimatic conditions. We examined how variability in precipitation affected streamflow using 21 years of daily streamflow and precipitation data from five watersheds at the Coweeta Hydrologic Laboratory in southwestern North Carolina, USA. The gauged watersheds contained both coniferous and deciduous vegetation, dominant north and south aspects, and differing precipitation magnitudes. Lag‐correlations between precipitation and runoff ratios across a range of temporal resolutions indicated strong influence of past precipitation (i.e., watershed memory). At all time‐scales, runoff ratios strongly depended on the precipitation of previous time steps. At monthly time scales, the influence of past precipitation was detectable for up to 7 months. At seasonal time scales, the previous season had a greater effect on a season's runoff ratio than the same season's precipitation. At annual time scales, the previous year was equally important for a year's runoff ratio than the same year's precipitation. Estimated watershed storage through time and specifically the previous year's storage state was strongly correlated with the residuals of a regression between annual precipitation and annual runoff, partially explaining observed variability in annual runoff in watersheds with deep soils. This effect was less pronounced in the steepest watershed that also contained shallow soils. We suggest that the location of a watershed on a nonlinear watershed‐scale storage‐release curve can explain differences in runoff during growing and dormant season between watersheds with different annual evapotranspiration.}, number={3}, journal={WATER RESOURCES RESEARCH}, author={Nippgen, Fabian and McGlynn, Brian L. and Emanuel, Ryan E. and Vose, James M.}, year={2016}, month={Mar}, pages={1673–1695} }
 @article{coulston_wear_vose_2015, title={Complex forest dynamics indicate potential for slowing carbon accumulation in the southeastern United States}, volume={5}, ISSN={["2045-2322"]}, DOI={10.1038/srep08002}, abstractNote={Over the past century forest regrowth in Europe and North America expanded forest carbon (C) sinks and offset C emissions but future C accumulation is uncertain. Policy makers need insights into forest C dynamics as they anticipate emissions futures and goals. We used land use and forest inventory data to estimate how forest C dynamics have changed in the southeastern United States and attribute changes to land use, management, and disturbance causes. From 2007-2012, forests yielded a net sink of C because of net land use change (+6.48 Tg C yr(-1)) and net biomass accumulation (+75.4 Tg C yr(-1)). Forests disturbed by weather, insect/disease, and fire show dampened yet positive forest C changes (+1.56, +1.4, +5.48 Tg C yr(-1), respectively). Forest cutting caused net decreases in C (-76.7 Tg C yr(-1)) but was offset by forest growth (+143.77 Tg C yr(-1)). Forest growth rates depend on age or stage of development and projected C stock changes indicate a gradual slowing of carbon accumulation with anticipated forest aging (a reduction of 9.5% over the next five years). Additionally, small shifts in land use transitions consistent with economic futures resulted in a 40.6% decrease in C accumulation.}, journal={SCIENTIFIC REPORTS}, author={Coulston, John W. and Wear, David N. and Vose, James M.}, year={2015}, month={Jan} }
 @article{rice_emanuel_vose_nelson_2015, title={Continental U.S. streamflow trends from 1940 to 2009 and their relationships with watershed spatial characteristics}, volume={51}, ISSN={0043-1397}, url={http://dx.doi.org/10.1002/2014WR016367}, DOI={10.1002/2014wr016367}, abstractNote={Changes in streamflow are an important area of ongoing research in the hydrologic sciences. To better understand spatial patterns in past changes in streamflow, we examined relationships between watershed‐scale spatial characteristics and trends in streamflow. Trends in streamflow were identified by analyzing mean daily flow observations between 1940 and 2009 from 967 U.S. Geological Survey stream gages. Results indicated that streamflow across the continental U.S., as a whole, increased while becoming less extreme between 1940 and 2009. However, substantial departures from the continental U.S. (CONUS) scale pattern occurred at the regional scale, including increased annual maxima, decreased annual minima, overall drying trends, and changes in streamflow variability. A subset of watersheds belonging to a reference data set exhibited significantly smaller trend magnitudes than those observed in nonreference watersheds. Boosted regression tree models were applied to examine the influence of watershed characteristics on streamflow trend magnitudes at both the CONUS and regional scale. Geographic location was found to be of particular importance at the CONUS scale while local variability in hydroclimate and topography tended to have a strong influence on regional‐scale patterns in streamflow trends. This methodology facilitates detailed, data‐driven analyses of how the characteristics of individual watersheds interact with large‐scale hydroclimate forces to influence how changes in streamflow manifest.}, number={8}, journal={Water Resources Research}, publisher={American Geophysical Union (AGU)}, author={Rice, Joshua S. and Emanuel, Ryan E. and Vose, James M. and Nelson, Stacy A. C.}, year={2015}, month={Aug}, pages={6262–6275} }
 @article{elliott_vose_knoepp_clinton_kloeppel_2015, title={Functional Role of the Herbaceous Layer in Eastern Deciduous Forest Ecosystems}, volume={18}, ISSN={["1435-0629"]}, DOI={10.1007/s10021-014-9825-x}, number={2}, journal={ECOSYSTEMS}, author={Elliott, Katherine J. and Vose, James M. and Knoepp, Jennifer D. and Clinton, Barton D. and Kloeppel, Brian D.}, year={2015}, month={Mar}, pages={221–236} }
 @article{elliott_vose_rankin_2014, title={Herbaceous species composition and richness of mesophytic cove forests in the southern Appalachians: synthesis and knowledge gaps}, volume={141}, ISSN={["1940-0616"]}, DOI={10.3159/torrey-d-13-00054.1}, abstractNote={Abstract We synthesized the current information on mesophytic cove forests in the southern Appalachians, assessed the range of variation in herb species composition and diversity in stands with different disturbance histories and environmental conditions, identified key knowledge gaps, and suggested approaches to fill these knowledge gaps. The purpose of this synthesis was to provide information to forest managers to help make decisions about conservation assessments and strategies for rich cove forests in the southern Appalachians. An important finding is that no single study or data set can provide conclusive evidence or clear management strategies. However, an overriding conclusion is that the magnitude of impact and the management actions necessary to restore herbaceous communities are directly proportional to the severity of disturbance, current condition (e.g., presence of Rhododendron), site heterogeneity, and historical land use (e.g., agricultural activity). These factors plus a host of other stressors (e.g., climate variability, air pollution, invasives) are likely to have a strong influence on the highly variable patterns observed when comparing herbaceous diversity of ‘old-growth’ or uncut forests to human disturbed forests (e.g., cutting, air pollution, conversion, invasive plants or insects). Results from this review reinforce our premise that factors controlling herbaceous species presence and abundance are highly complex, thus broad generalizations about the impacts of a single factor such as logging should be interpreted with caution. Of the stressors known to affect forest trees (e.g., pests and pathogens, acidic deposition, air pollution, drought, and wind), little to no information exists on how these same stressors will affect herbaceous plants. A limited number of studies have examined the demography or physiology of forest herbs, particularly across all life stages. While the demography of a few genera have been studied (e.g., Hexastylis, Asarum, Trillium, Arisaema, Goodyera, Hepatica), little to no information exists for the majority of woodland herbs. Species identity is important when considering management of rich cove forests. Diversity may increase following canopy disturbances that favor recruitment of early-seral herbaceous species; therefore, simple indices of diversity (H′, S, and E) are not the best measure of recovery in mesophytic rich coves, particularly where shade-adapted ‘rich-cove indicator’ species have been replaced by these species. Species-specific life histories and the influence of prevailing site conditions are important lines of research for understanding recovery and sustainability of mesophytic rich cove forests.}, number={1}, journal={JOURNAL OF THE TORREY BOTANICAL SOCIETY}, author={Elliott, Katherine J. and Vose, James M. and Rankin, Duke}, year={2014}, month={Jan}, pages={39–71} }
 @article{novick_brantley_miniat_walker_vose_2014, title={Inferring the contribution of advection to total ecosystem scalar fluxes over a tall forest in complex terrain}, volume={185}, ISSN={["1873-2240"]}, DOI={10.1016/j.agrformet.2013.10.010}, abstractNote={Multiple data streams from a new flux tower located in complex and heterogeneous terrain at the Coweeta Hydrologic Laboratory (North Carolina, USA) were integrated to identify periods of advective flow regimes. Drainage flows were expected a priori, due to the location of the measurement site at the base of a long, gently-sloping valley. Drainage flow was confirmed by examining vertical profile measurements of wind direction and by estimating vertical advection fluxes. The vertical advection flux of CO2 was most significant in early morning (000–0600 h) during the growing season, when it averaged ∼5 μmol m−2 s−1. Horizontal advection flux of CO2 was not directly measured in this study; however, an expected exponential relationship between nocturnal ecosystem respiration (RE) and air temperature was recovered when horizontal advection of CO2 was assumed to be negatively correlated to vertical advection, or when data were limited to periods when measured vertical advection fluxes were small. Taken together, these data imply the presence of a negative horizontal advection CO2 flux during nocturnal periods characterized by positive vertical advection of CO2. Daytime periods were characterized by consistent anabatic (up-valley) flows in mid- to late-morning (0500–1200 h) and consistent katabatic (down-valley) flows in the afternoon. A combination of above-canopy flux profile measurements, energy balance closure estimates, and flux footprint estimates suggest that during periods of up-valley wind flow, the flux footprint frequently exceeds the ecosystem dimensions, and horizontal advection fluxes related to landscape heterogeneity were a significant component of the total ecosystem flux of CO2. We used sap flux from individual trees beneath the tower to explore diurnal patterns in stomatal conductance in order to evaluate gapfilling approaches for the unreliable morning data. The relationship between stomatal conductance and vapor pressure deficit was similar in morning and afternoon periods, and we conclude that gapfilling morning data with models driven by afternoon data is a reasonable approach at this site. In general, results were consistent with other studies showing that the advection and wind flow regimes in complex terrain are highly site specific; nonetheless, the site characterization strategy developed here, when used together with independent estimates of components of the ecosystem carbon flux, could be generally applied in other sites to better understand the contribution of advection to the total ecosystem flux.}, journal={AGRICULTURAL AND FOREST METEOROLOGY}, author={Novick, K. and Brantley, S. and Miniat, C. Ford and Walker, J. and Vose, J. M.}, year={2014}, month={Feb}, pages={1–13} }
 @misc{vose_wear_mayfield_nelson_2013, title={Hemlock woolly adelgid in the southern Appalachians: Control strategies, ecological impacts, and potential management responses}, volume={291}, ISSN={["1872-7042"]}, DOI={10.1016/j.foreco.2012.11.002}, abstractNote={Hemlock woolly adelgid (Adelges tsugae Annad; or HWA) is a non-native invasive pest that attacks and kills eastern hemlock (Tsuga canadensis (L.) Carrière) and Carolina hemlock (Tsuga caroliniana Engelm.). Hemlock is a “foundation species” due to its strong influence on ecosystem structure and function, especially in riparian areas. HWA management involves the integrated use of multiple approaches including chemical control, biological control, cultural treatments, host resistance, and host gene conservation. Despite extensive control efforts, large areas in the eastern US, but especially in the southern Appalachian region, have experienced extensive hemlock mortality. Most of the short-term impacts of HWA induced mortality on ecosystem structure and function are localized and small; however, long-term impacts such as large pulses of woody debris and changes in species composition that impact structure and function could be significant. Using a decision analysis framework, land managers should begin to strategically implement land management decisions to address observed short-term impacts and plan and manage for projected longer-term impacts. In order to maintain ecosystem services in response to long-term impacts, restoration efforts may require novel approaches, such as the introduction of non-native species, facilitated movement of native species to new habitats (e.g., white pine), and aggressive management of existing species (e.g., Rhododendron) with mechanical removal, fire, or chemicals.}, journal={FOREST ECOLOGY AND MANAGEMENT}, author={Vose, James M. and Wear, David N. and Mayfield, Albert E., III and Nelson, C. Dana}, year={2013}, month={Mar}, pages={209–219} }