{"title":"Sensitivity of montane grassland water fluxes to warming and elevated CO2 from local to catchment scale: A case study from the Austrian Alps","authors":"","doi":"10.1016/j.ejrh.2024.101970","DOIUrl":null,"url":null,"abstract":"<div><p>Study region: Montane grassland within the Gulling catchment, Austrian Alps. Study focus: A climate-change experiment in a grassland ecosystem used lysimeters and HYDRUS-1D models to quantify changes in evapotranspiration (ET) and groundwater recharge (GWR) due to warming (+3 °C) and elevated <span><math><msub><mrow><mi>CO</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span> concentrations (<span><math><mrow><mi>Δ</mi><msub><mrow><mi>CO</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span>; +300 ppm). Findings at the plot-scale were generalized and transferred to the surrounding catchment, half comprised of grassland, using three lumped rainfall–runoff models and two spatially-distributed Community Water Models, differing in soil hydraulic properties.</p><p>New hydrological insights for the region: Warming increased ET and decreased GWR and river discharge compared to ambient conditions. <span><math><mrow><mi>Δ</mi><msub><mrow><mi>CO</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span> increased stomatal resistance, which partially offset warming effects. In scenarios combining warming and <span><math><mrow><mi>Δ</mi><msub><mrow><mi>CO</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span>, the impact of warming was higher than <span><math><mrow><mi>Δ</mi><msub><mrow><mi>CO</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span> effect. Elevation influenced the sensitivity of ET to warming, which was greater at the catchment scale than at the plot scale, while GWR was more sensitive to warming at the plot scale. Under dry conditions, GWR and discharge exhibited increased sensitivity to warming at both scales. HYDRUS-1D successfully reproduced lysimeter experiment results and their sensitivity to warming and <span><math><mrow><mi>Δ</mi><msub><mrow><mi>CO</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span>. Despite model agreement on water flux sensitivity to climate changes, the varying response magnitudes highlight the need for a multi-model approach in climate impact assessments. This study provides insights into how climate change might impact hydrological dynamics of montane grassland systems across the Central European Alps.</p></div>","PeriodicalId":48620,"journal":{"name":"Journal of Hydrology-Regional Studies","volume":null,"pages":null},"PeriodicalIF":4.7000,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2214581824003197/pdfft?md5=aa5fabc922873653387e16e2c07981b8&pid=1-s2.0-S2214581824003197-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Hydrology-Regional Studies","FirstCategoryId":"89","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2214581824003197","RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"WATER RESOURCES","Score":null,"Total":0}
引用次数: 0
Abstract
Study region: Montane grassland within the Gulling catchment, Austrian Alps. Study focus: A climate-change experiment in a grassland ecosystem used lysimeters and HYDRUS-1D models to quantify changes in evapotranspiration (ET) and groundwater recharge (GWR) due to warming (+3 °C) and elevated concentrations (; +300 ppm). Findings at the plot-scale were generalized and transferred to the surrounding catchment, half comprised of grassland, using three lumped rainfall–runoff models and two spatially-distributed Community Water Models, differing in soil hydraulic properties.
New hydrological insights for the region: Warming increased ET and decreased GWR and river discharge compared to ambient conditions. increased stomatal resistance, which partially offset warming effects. In scenarios combining warming and , the impact of warming was higher than effect. Elevation influenced the sensitivity of ET to warming, which was greater at the catchment scale than at the plot scale, while GWR was more sensitive to warming at the plot scale. Under dry conditions, GWR and discharge exhibited increased sensitivity to warming at both scales. HYDRUS-1D successfully reproduced lysimeter experiment results and their sensitivity to warming and . Despite model agreement on water flux sensitivity to climate changes, the varying response magnitudes highlight the need for a multi-model approach in climate impact assessments. This study provides insights into how climate change might impact hydrological dynamics of montane grassland systems across the Central European Alps.
期刊介绍:
Journal of Hydrology: Regional Studies publishes original research papers enhancing the science of hydrology and aiming at region-specific problems, past and future conditions, analysis, review and solutions. The journal particularly welcomes research papers that deliver new insights into region-specific hydrological processes and responses to changing conditions, as well as contributions that incorporate interdisciplinarity and translational science.