Experimental Exclusion of Guanaco Grazing Increases Cover, Diversity, Land Function and Plant Recruitment in Patagonia
Semiarid Patagonia represents 25% of the rangeland area in Argentina, and sheep overgrazing has degraded about a third of it in the past. In this century, depleted domestic stocks have mostly stabilized, but Guanaco populations have grown. These native camelids share habitat and diets with sheep, bu...
| Main Authors: | , , |
|---|---|
| Format: | info:ar-repo/semantics/artículo |
| Language: | Inglés |
| Published: |
Tech Science Press
2024
|
| Subjects: | |
| Online Access: | http://hdl.handle.net/20.500.12123/18961 https://www.techscience.com/phyton/v93n7/57482 https://doi.org/10.32604/phyton.2024.052534 |
| _version_ | 1855037947972157440 |
|---|---|
| author | Cepeda, Carla Tamara Oliva, Gabriel Esteban Ferrante, Daniela |
| author_browse | Cepeda, Carla Tamara Ferrante, Daniela Oliva, Gabriel Esteban |
| author_facet | Cepeda, Carla Tamara Oliva, Gabriel Esteban Ferrante, Daniela |
| author_sort | Cepeda, Carla Tamara |
| collection | INTA Digital |
| description | Semiarid Patagonia represents 25% of the rangeland area in Argentina, and sheep overgrazing has degraded about a third of it in the past. In this century, depleted domestic stocks have mostly stabilized, but Guanaco populations have grown. These native camelids share habitat and diets with sheep, but their effect on vegetation is poorly understood and has long been debated. We set up an exclusion experiment in Monte León and Cañadón Vaca, a semiarid shrubland grassland in southern Patagonia, currently grazed only by guanacos. Vegetation baselines were studied in 2016 in twelve plots, and half of them were protected from guanaco grazing. Thirty-six plots were cleared to study revegetation. Vegetation was reassessed in 2021, and changes were evaluated using a paired t-test. Within protected plots, vegetation cover increased, bare soil diminished, and vegetated patches grew in size, but the density of the patch-interpatch arrangement did not change. Biodiversity, measured by richness and the Shannon-Wiener (SW) index, grew significantly. Nutrient recycling increased, as did the Stability and Infiltration Land Function indexes, although these last differences were not significant. Vegetation cover under guanaco grazing also increased, mainly due to the growth of dwarf shrubs, a typical tendency in sheep grazing-induced transitions in the region. Vegetated patches under grazing fragmented, resulting in smaller patches and denser patch structures, while diversity and land function indexes remained unchanged. Young plants established in cleared plots without guanacos showed higher cover density and individual size. These effects are similar to those observed in
numerous experimental sheep exclosures. Guanaco grazing may thus prevent restoration and contribute to the generalized land degradation processes that overgrazing has been causing in Patagonia for over a century. |
| format | info:ar-repo/semantics/artículo |
| id | INTA18961 |
| institution | Instituto Nacional de Tecnología Agropecuaria (INTA -Argentina) |
| language | Inglés |
| publishDate | 2024 |
| publishDateRange | 2024 |
| publishDateSort | 2024 |
| publisher | Tech Science Press |
| publisherStr | Tech Science Press |
| record_format | dspace |
| spelling | INTA189612024-10-29T11:42:58Z Experimental Exclusion of Guanaco Grazing Increases Cover, Diversity, Land Function and Plant Recruitment in Patagonia Cepeda, Carla Tamara Oliva, Gabriel Esteban Ferrante, Daniela Herbivory Biodiversity Overgrazing Carrying Capacity Fauna Guanacos Land Degradation Grazing Herbivoría Biodiversidad Sobrepastoreo Capacidad de Carga Lama guanicoe Guanaco Degradación de Tierras Pastoreo Vegetated Patches Parches de Vegetación Región Patagónica Semiarid Patagonia represents 25% of the rangeland area in Argentina, and sheep overgrazing has degraded about a third of it in the past. In this century, depleted domestic stocks have mostly stabilized, but Guanaco populations have grown. These native camelids share habitat and diets with sheep, but their effect on vegetation is poorly understood and has long been debated. We set up an exclusion experiment in Monte León and Cañadón Vaca, a semiarid shrubland grassland in southern Patagonia, currently grazed only by guanacos. Vegetation baselines were studied in 2016 in twelve plots, and half of them were protected from guanaco grazing. Thirty-six plots were cleared to study revegetation. Vegetation was reassessed in 2021, and changes were evaluated using a paired t-test. Within protected plots, vegetation cover increased, bare soil diminished, and vegetated patches grew in size, but the density of the patch-interpatch arrangement did not change. Biodiversity, measured by richness and the Shannon-Wiener (SW) index, grew significantly. Nutrient recycling increased, as did the Stability and Infiltration Land Function indexes, although these last differences were not significant. Vegetation cover under guanaco grazing also increased, mainly due to the growth of dwarf shrubs, a typical tendency in sheep grazing-induced transitions in the region. Vegetated patches under grazing fragmented, resulting in smaller patches and denser patch structures, while diversity and land function indexes remained unchanged. Young plants established in cleared plots without guanacos showed higher cover density and individual size. These effects are similar to those observed in numerous experimental sheep exclosures. Guanaco grazing may thus prevent restoration and contribute to the generalized land degradation processes that overgrazing has been causing in Patagonia for over a century. EEA Santa Cruz Fil: Cepeda, Carla Tamara. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina Fil: Oliva, Gabriel Esteban. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina. Fil: Oliva, Gabriel Esteban. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina. Fil: Ferrante, Daniela. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina. Fil: Ferrante, Daniela. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina. 2024-08-16T10:24:14Z 2024-08-16T10:24:14Z 2024-07-30 info:ar-repo/semantics/artículo info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion http://hdl.handle.net/20.500.12123/18961 https://www.techscience.com/phyton/v93n7/57482 Cepeda, C., Oliva, G., Ferrante, D. (2024). Experimental exclusion of guanaco grazing increases cover, diversity, land function and plant recruitment in patagonia. Phyton-International Journal of Experimental Botany, 93(7), 1383-1401. https://doi.org/10.32604/phyton.2024.052534 1851-5657 (online) 0031-9457 (print) https://doi.org/10.32604/phyton.2024.052534 eng info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by-nc-sa/4.0/ Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) application/pdf Tech Science Press Phyton-International Journal of Experimental Botany 93 (7) : 1383-1401. (2024) |
| spellingShingle | Herbivory Biodiversity Overgrazing Carrying Capacity Fauna Guanacos Land Degradation Grazing Herbivoría Biodiversidad Sobrepastoreo Capacidad de Carga Lama guanicoe Guanaco Degradación de Tierras Pastoreo Vegetated Patches Parches de Vegetación Región Patagónica Cepeda, Carla Tamara Oliva, Gabriel Esteban Ferrante, Daniela Experimental Exclusion of Guanaco Grazing Increases Cover, Diversity, Land Function and Plant Recruitment in Patagonia |
| title | Experimental Exclusion of Guanaco Grazing Increases Cover, Diversity, Land Function and Plant Recruitment in Patagonia |
| title_full | Experimental Exclusion of Guanaco Grazing Increases Cover, Diversity, Land Function and Plant Recruitment in Patagonia |
| title_fullStr | Experimental Exclusion of Guanaco Grazing Increases Cover, Diversity, Land Function and Plant Recruitment in Patagonia |
| title_full_unstemmed | Experimental Exclusion of Guanaco Grazing Increases Cover, Diversity, Land Function and Plant Recruitment in Patagonia |
| title_short | Experimental Exclusion of Guanaco Grazing Increases Cover, Diversity, Land Function and Plant Recruitment in Patagonia |
| title_sort | experimental exclusion of guanaco grazing increases cover diversity land function and plant recruitment in patagonia |
| topic | Herbivory Biodiversity Overgrazing Carrying Capacity Fauna Guanacos Land Degradation Grazing Herbivoría Biodiversidad Sobrepastoreo Capacidad de Carga Lama guanicoe Guanaco Degradación de Tierras Pastoreo Vegetated Patches Parches de Vegetación Región Patagónica |
| url | http://hdl.handle.net/20.500.12123/18961 https://www.techscience.com/phyton/v93n7/57482 https://doi.org/10.32604/phyton.2024.052534 |
| work_keys_str_mv | AT cepedacarlatamara experimentalexclusionofguanacograzingincreasescoverdiversitylandfunctionandplantrecruitmentinpatagonia AT olivagabrielesteban experimentalexclusionofguanacograzingincreasescoverdiversitylandfunctionandplantrecruitmentinpatagonia AT ferrantedaniela experimentalexclusionofguanacograzingincreasescoverdiversitylandfunctionandplantrecruitmentinpatagonia |