Interspecific competition interacts with the spatial distribution of a palatable grass to reduce its recruitment

Most arid and semiarid ecosystems around the world have been grazed by domestic herbivores. In many cases, grazing has degraded vegetation and soil. The possibility of restoring rangeland's good condition depends, partially, on the ability of remaining populations of desirable species to recove...

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Publicado: 2005
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Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_15507424_v58_n4_p393_Cipriotti
http://hdl.handle.net/20.500.12110/paper_15507424_v58_n4_p393_Cipriotti
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spelling paper:paper_15507424_v58_n4_p393_Cipriotti2023-06-08T16:21:35Z Interspecific competition interacts with the spatial distribution of a palatable grass to reduce its recruitment Associations Bromus pictus Climatic variation Patagonian steppes Rangelands Recovery Refuges Spatial patterns climate change palatability rangeland spatial distribution Patagonia South America Western Hemisphere World Arida Bromus Bromus pictus Ovis aries Poaceae Most arid and semiarid ecosystems around the world have been grazed by domestic herbivores. In many cases, grazing has degraded vegetation and soil. The possibility of restoring rangeland's good condition depends, partially, on the ability of remaining populations of desirable species to recover. In this work, we studied the exact spatial distribution of remaining palatable adult plants in fields with different grazing history (i.e., seed sources) and quantified the effect of interspecific competition with less palatable grasses on seedling emergence and survival (i.e., regeneration constraints). We worked in a Patagonian steppe composed of shrubs and perennial tussock grasses that has been grazed by sheep for >100 years. In order to evaluate the location of seed sources, we mapped the location of a palatable species (Bromus pictus Hook.) in paddocks with different long-term grazing intensity. In addition, we sowed seeds of B. pictus close to 2 dominant, less palatable grasses in 2 different years to evaluate the role of interspecific interactions on regeneration and the effects of climate variability. The proportion of B. pictus plants growing in protected places near less palatable species significantly increased with grazing intensity. Competition effects on emergence, survival, and growth depended on the year's moisture regime. During the dry year, competition with less palatable grasses reduced the emergence, survival, height, and number of leaves of palatable grass seedlings by 30%, 55%, 48%, and 40%, respectively. In the wet year, there were no effects of competition on emergence and height, and the effects on survival depended on the species of the less palatable neighbors. Our study supports the idea that management for recovering degraded rangelands in this ecosystem may benefit from considering the spatial distribution of remaining plants. It also indicates that the susceptibility of demographic processes to interspecific competition depends on the year and neighbor species. 2005 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_15507424_v58_n4_p393_Cipriotti http://hdl.handle.net/20.500.12110/paper_15507424_v58_n4_p393_Cipriotti
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Associations
Bromus pictus
Climatic variation
Patagonian steppes
Rangelands
Recovery
Refuges
Spatial patterns
climate change
palatability
rangeland
spatial distribution
Patagonia
South America
Western Hemisphere
World
Arida
Bromus
Bromus pictus
Ovis aries
Poaceae
spellingShingle Associations
Bromus pictus
Climatic variation
Patagonian steppes
Rangelands
Recovery
Refuges
Spatial patterns
climate change
palatability
rangeland
spatial distribution
Patagonia
South America
Western Hemisphere
World
Arida
Bromus
Bromus pictus
Ovis aries
Poaceae
Interspecific competition interacts with the spatial distribution of a palatable grass to reduce its recruitment
topic_facet Associations
Bromus pictus
Climatic variation
Patagonian steppes
Rangelands
Recovery
Refuges
Spatial patterns
climate change
palatability
rangeland
spatial distribution
Patagonia
South America
Western Hemisphere
World
Arida
Bromus
Bromus pictus
Ovis aries
Poaceae
description Most arid and semiarid ecosystems around the world have been grazed by domestic herbivores. In many cases, grazing has degraded vegetation and soil. The possibility of restoring rangeland's good condition depends, partially, on the ability of remaining populations of desirable species to recover. In this work, we studied the exact spatial distribution of remaining palatable adult plants in fields with different grazing history (i.e., seed sources) and quantified the effect of interspecific competition with less palatable grasses on seedling emergence and survival (i.e., regeneration constraints). We worked in a Patagonian steppe composed of shrubs and perennial tussock grasses that has been grazed by sheep for >100 years. In order to evaluate the location of seed sources, we mapped the location of a palatable species (Bromus pictus Hook.) in paddocks with different long-term grazing intensity. In addition, we sowed seeds of B. pictus close to 2 dominant, less palatable grasses in 2 different years to evaluate the role of interspecific interactions on regeneration and the effects of climate variability. The proportion of B. pictus plants growing in protected places near less palatable species significantly increased with grazing intensity. Competition effects on emergence, survival, and growth depended on the year's moisture regime. During the dry year, competition with less palatable grasses reduced the emergence, survival, height, and number of leaves of palatable grass seedlings by 30%, 55%, 48%, and 40%, respectively. In the wet year, there were no effects of competition on emergence and height, and the effects on survival depended on the species of the less palatable neighbors. Our study supports the idea that management for recovering degraded rangelands in this ecosystem may benefit from considering the spatial distribution of remaining plants. It also indicates that the susceptibility of demographic processes to interspecific competition depends on the year and neighbor species.
title Interspecific competition interacts with the spatial distribution of a palatable grass to reduce its recruitment
title_short Interspecific competition interacts with the spatial distribution of a palatable grass to reduce its recruitment
title_full Interspecific competition interacts with the spatial distribution of a palatable grass to reduce its recruitment
title_fullStr Interspecific competition interacts with the spatial distribution of a palatable grass to reduce its recruitment
title_full_unstemmed Interspecific competition interacts with the spatial distribution of a palatable grass to reduce its recruitment
title_sort interspecific competition interacts with the spatial distribution of a palatable grass to reduce its recruitment
publishDate 2005
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_15507424_v58_n4_p393_Cipriotti
http://hdl.handle.net/20.500.12110/paper_15507424_v58_n4_p393_Cipriotti
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