The ecohydrological imprint of deforestation in the semiarid Chaco: insights from the last forest remnants of a highly cultivated landscape
The semiarid Chaco plains present one of the highest rates of forest clearing and agricultural expansion of the world. In other semiarid plains, such massive vegetation replacements initiated a groundwater recharge and salt mobilization process that, after decades, raised regional water tables and s...
| Autores principales: | , , , , |
|---|---|
| Formato: | info:ar-repo/semantics/artículo |
| Lenguaje: | Inglés |
| Publicado: |
2018
|
| Materias: | |
| Acceso en línea: | https://onlinelibrary.wiley.com/doi/abs/10.1002/hyp.10901 http://hdl.handle.net/20.500.12123/3061 https://doi.org/10.1002/hyp.10901 |
| _version_ | 1855035077121015808 |
|---|---|
| author | Giménez, Raúl Mercau, Jorge Luis Nosetto, Marcelo Daniel Páez, Ricardo Jobbagy Gampel, Esteban Gabriel |
| author_browse | Giménez, Raúl Jobbagy Gampel, Esteban Gabriel Mercau, Jorge Luis Nosetto, Marcelo Daniel Páez, Ricardo |
| author_facet | Giménez, Raúl Mercau, Jorge Luis Nosetto, Marcelo Daniel Páez, Ricardo Jobbagy Gampel, Esteban Gabriel |
| author_sort | Giménez, Raúl |
| collection | INTA Digital |
| description | The semiarid Chaco plains present one of the highest rates of forest clearing and agricultural expansion of the world. In other semiarid plains, such massive vegetation replacements initiated a groundwater recharge and salt mobilization process that, after decades, raised regional water tables and salts to the surface, degrading agricultural and natural ecosystems. Indirect evidence suggests that this process (known as dryland salinity) began in the Chaco plains. Multiple approaches (deep soil profiles, geoelectric surveys and monitoring of groundwater salinity, level and isotopic composition) were combined to assess the dryland salinity status in one of the oldest and most active agricultural hotspots of the region, where isolated forest remnants occupy an extremely flat cultivated matrix. Full vadose moisture and chloride profiles from paired agriculture‐forest stands (17 profiles, six sites) revealed the following: a generalized onset of deep drainage with cultivation (32 to >87 mm year−1), full leaching of native chloride pools (13.7 ± 2.5 kg m−2) down to the water table after >40 years following clearing and differential groundwater table rises (0.7 to 2 m shallower water tables under agriculture than under neighbouring forests). Continuous level monitoring showed abrupt water table rises under annual crops (up to 2.6 m in 15 days) not seen under forests or pastures. Varying deep drainage rates and groundwater isotopic composition under agricultural plots suggest that these pulses are strongly modulated by crop choices and sequences. In contrast to other dryland salinity‐affected areas of the world, forest remnants in the study area (10–20% of the area) are not only surviving the observed hydrological shifts but also sustaining active salty groundwater transpirative discharge, as evidenced by continuous water table records. The overall impact of these forest remnants on lowering neighbouring water tables would be limited by the low hydraulic conductivity of the sediments. As highly cultivated areas of the Chaco evolve to new hydrological conditions of shallower saline water tables, innovative crop rotations that minimize recharge, enhance transpirative discharge and tolerate salinity will be needed |
| format | info:ar-repo/semantics/artículo |
| id | INTA3061 |
| institution | Instituto Nacional de Tecnología Agropecuaria (INTA -Argentina) |
| language | Inglés |
| publishDate | 2018 |
| publishDateRange | 2018 |
| publishDateSort | 2018 |
| record_format | dspace |
| spelling | INTA30612019-03-27T13:55:46Z The ecohydrological imprint of deforestation in the semiarid Chaco: insights from the last forest remnants of a highly cultivated landscape Giménez, Raúl Mercau, Jorge Luis Nosetto, Marcelo Daniel Páez, Ricardo Jobbagy Gampel, Esteban Gabriel Deforestación Ecología Hidrología Bosques Agricultura Deforestation Ecology Hydrology Forests Agriculture Chaco Semiárido, San Luis Expansión Agrícola The semiarid Chaco plains present one of the highest rates of forest clearing and agricultural expansion of the world. In other semiarid plains, such massive vegetation replacements initiated a groundwater recharge and salt mobilization process that, after decades, raised regional water tables and salts to the surface, degrading agricultural and natural ecosystems. Indirect evidence suggests that this process (known as dryland salinity) began in the Chaco plains. Multiple approaches (deep soil profiles, geoelectric surveys and monitoring of groundwater salinity, level and isotopic composition) were combined to assess the dryland salinity status in one of the oldest and most active agricultural hotspots of the region, where isolated forest remnants occupy an extremely flat cultivated matrix. Full vadose moisture and chloride profiles from paired agriculture‐forest stands (17 profiles, six sites) revealed the following: a generalized onset of deep drainage with cultivation (32 to >87 mm year−1), full leaching of native chloride pools (13.7 ± 2.5 kg m−2) down to the water table after >40 years following clearing and differential groundwater table rises (0.7 to 2 m shallower water tables under agriculture than under neighbouring forests). Continuous level monitoring showed abrupt water table rises under annual crops (up to 2.6 m in 15 days) not seen under forests or pastures. Varying deep drainage rates and groundwater isotopic composition under agricultural plots suggest that these pulses are strongly modulated by crop choices and sequences. In contrast to other dryland salinity‐affected areas of the world, forest remnants in the study area (10–20% of the area) are not only surviving the observed hydrological shifts but also sustaining active salty groundwater transpirative discharge, as evidenced by continuous water table records. The overall impact of these forest remnants on lowering neighbouring water tables would be limited by the low hydraulic conductivity of the sediments. As highly cultivated areas of the Chaco evolve to new hydrological conditions of shallower saline water tables, innovative crop rotations that minimize recharge, enhance transpirative discharge and tolerate salinity will be needed EEA San Luis Fil: Giménez, Raúl. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis; Argentina Fil: Mercau, Jorge Luis. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria San Luis; Argentina Fil: Nosetto, Marcelo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis; Argentina Fil: Páez, Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis; Argentina Fil: Jobbagy Gampel, Esteban Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis; Argentina 2018-08-14T12:36:05Z 2018-08-14T12:36:05Z 2016-07 info:ar-repo/semantics/artículo info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion https://onlinelibrary.wiley.com/doi/abs/10.1002/hyp.10901 http://hdl.handle.net/20.500.12123/3061 0885-6087 1099-1085 https://doi.org/10.1002/hyp.10901 eng info:eu-repo/semantics/restrictedAccess application/pdf Hydrological Processes 30 (15) : 2603-2616 (July 2016) |
| spellingShingle | Deforestación Ecología Hidrología Bosques Agricultura Deforestation Ecology Hydrology Forests Agriculture Chaco Semiárido, San Luis Expansión Agrícola Giménez, Raúl Mercau, Jorge Luis Nosetto, Marcelo Daniel Páez, Ricardo Jobbagy Gampel, Esteban Gabriel The ecohydrological imprint of deforestation in the semiarid Chaco: insights from the last forest remnants of a highly cultivated landscape |
| title | The ecohydrological imprint of deforestation in the semiarid Chaco: insights from the last forest remnants of a highly cultivated landscape |
| title_full | The ecohydrological imprint of deforestation in the semiarid Chaco: insights from the last forest remnants of a highly cultivated landscape |
| title_fullStr | The ecohydrological imprint of deforestation in the semiarid Chaco: insights from the last forest remnants of a highly cultivated landscape |
| title_full_unstemmed | The ecohydrological imprint of deforestation in the semiarid Chaco: insights from the last forest remnants of a highly cultivated landscape |
| title_short | The ecohydrological imprint of deforestation in the semiarid Chaco: insights from the last forest remnants of a highly cultivated landscape |
| title_sort | ecohydrological imprint of deforestation in the semiarid chaco insights from the last forest remnants of a highly cultivated landscape |
| topic | Deforestación Ecología Hidrología Bosques Agricultura Deforestation Ecology Hydrology Forests Agriculture Chaco Semiárido, San Luis Expansión Agrícola |
| url | https://onlinelibrary.wiley.com/doi/abs/10.1002/hyp.10901 http://hdl.handle.net/20.500.12123/3061 https://doi.org/10.1002/hyp.10901 |
| work_keys_str_mv | AT gimenezraul theecohydrologicalimprintofdeforestationinthesemiaridchacoinsightsfromthelastforestremnantsofahighlycultivatedlandscape AT mercaujorgeluis theecohydrologicalimprintofdeforestationinthesemiaridchacoinsightsfromthelastforestremnantsofahighlycultivatedlandscape AT nosettomarcelodaniel theecohydrologicalimprintofdeforestationinthesemiaridchacoinsightsfromthelastforestremnantsofahighlycultivatedlandscape AT paezricardo theecohydrologicalimprintofdeforestationinthesemiaridchacoinsightsfromthelastforestremnantsofahighlycultivatedlandscape AT jobbagygampelestebangabriel theecohydrologicalimprintofdeforestationinthesemiaridchacoinsightsfromthelastforestremnantsofahighlycultivatedlandscape AT gimenezraul ecohydrologicalimprintofdeforestationinthesemiaridchacoinsightsfromthelastforestremnantsofahighlycultivatedlandscape AT mercaujorgeluis ecohydrologicalimprintofdeforestationinthesemiaridchacoinsightsfromthelastforestremnantsofahighlycultivatedlandscape AT nosettomarcelodaniel ecohydrologicalimprintofdeforestationinthesemiaridchacoinsightsfromthelastforestremnantsofahighlycultivatedlandscape AT paezricardo ecohydrologicalimprintofdeforestationinthesemiaridchacoinsightsfromthelastforestremnantsofahighlycultivatedlandscape AT jobbagygampelestebangabriel ecohydrologicalimprintofdeforestationinthesemiaridchacoinsightsfromthelastforestremnantsofahighlycultivatedlandscape |