Granivore impact on soil-seed reserves in the central Monte desert, Argentina

1. Mechanisms of grass- and forb-seed input and output in the central Monte desert of Argentina were studied in 1995 to test the hypothesis that seed consumption by autumn-winter granivores, especially birds, has qualitative as well as quantitative effects on soil-seed reserves. 2. The abundance of...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autor principal: López de Casenave, Javier Néstor
Publicado: 1998
Materias:
Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_02698463_v12_n4_p640_Marone
http://hdl.handle.net/20.500.12110/paper_02698463_v12_n4_p640_Marone
Aporte de:
id paper:paper_02698463_v12_n4_p640_Marone
record_format dspace
spelling paper:paper_02698463_v12_n4_p640_Marone2023-06-08T15:24:31Z Granivore impact on soil-seed reserves in the central Monte desert, Argentina López de Casenave, Javier Néstor Granivorous birds Granivory Postdispersal seed loss Seed rain Soil-seed bank desert granivory seed bank temporal variation Argentina Animalia Aves 1. Mechanisms of grass- and forb-seed input and output in the central Monte desert of Argentina were studied in 1995 to test the hypothesis that seed consumption by autumn-winter granivores, especially birds, has qualitative as well as quantitative effects on soil-seed reserves. 2. The abundance of perennial grass seeds in late summer soils (≃ 2400 seeds m-2 or 0.36 g m-2) remained unchanged the following early spring (≃ 2700 seeds m-2 or 0.39 g m-2), despite the incorporation of about 3000 seeds m-2 or 0.71 g m-2 newly produced grass seeds during autumn-winter. Grass seeds appeared to be heavily consumed, especially the medium-sized ones. 3. The annual forb-seed bank was about the same size in late summer (≃ 5500 seeds m-2 or 1.34 g m-2) as in early spring (≃ 6500 seeds m-2 or 1.53 g m-2). Since forb-seed production had been relatively low (≃ 400 seeds m-2 or 0.12 g m-2), these seeds apparently suffered negligible postdispersal losses. 4. This pattern of grass- and forb-seed loss coincides with the pattern of seed consumption by granivorous birds - on average, 93% of seed mass in bird stomachs was from grass seeds, while only 7% was from forb seeds. 5, Further evidence of a major impact of bird foraging on seed reserves is that the mass of particular grass seeds that was lost from soils was positively correlated with the mass of such seeds in bird diets, and that the main target of bird consumption, i.e. medium-sized grass seeds, suffered the highest postdispersal loss. 6. It is concluded that autumn-winter granivores in the central Monte desert, particularly birds, mainly consume newly produced grass seeds and that they might have major qualitative as well as quantitative impacts on soil-seed reserves. Fil:De Casenave, J.L. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 1998 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_02698463_v12_n4_p640_Marone http://hdl.handle.net/20.500.12110/paper_02698463_v12_n4_p640_Marone
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Granivorous birds
Granivory
Postdispersal seed loss
Seed rain
Soil-seed bank
desert
granivory
seed bank
temporal variation
Argentina
Animalia
Aves
spellingShingle Granivorous birds
Granivory
Postdispersal seed loss
Seed rain
Soil-seed bank
desert
granivory
seed bank
temporal variation
Argentina
Animalia
Aves
López de Casenave, Javier Néstor
Granivore impact on soil-seed reserves in the central Monte desert, Argentina
topic_facet Granivorous birds
Granivory
Postdispersal seed loss
Seed rain
Soil-seed bank
desert
granivory
seed bank
temporal variation
Argentina
Animalia
Aves
description 1. Mechanisms of grass- and forb-seed input and output in the central Monte desert of Argentina were studied in 1995 to test the hypothesis that seed consumption by autumn-winter granivores, especially birds, has qualitative as well as quantitative effects on soil-seed reserves. 2. The abundance of perennial grass seeds in late summer soils (≃ 2400 seeds m-2 or 0.36 g m-2) remained unchanged the following early spring (≃ 2700 seeds m-2 or 0.39 g m-2), despite the incorporation of about 3000 seeds m-2 or 0.71 g m-2 newly produced grass seeds during autumn-winter. Grass seeds appeared to be heavily consumed, especially the medium-sized ones. 3. The annual forb-seed bank was about the same size in late summer (≃ 5500 seeds m-2 or 1.34 g m-2) as in early spring (≃ 6500 seeds m-2 or 1.53 g m-2). Since forb-seed production had been relatively low (≃ 400 seeds m-2 or 0.12 g m-2), these seeds apparently suffered negligible postdispersal losses. 4. This pattern of grass- and forb-seed loss coincides with the pattern of seed consumption by granivorous birds - on average, 93% of seed mass in bird stomachs was from grass seeds, while only 7% was from forb seeds. 5, Further evidence of a major impact of bird foraging on seed reserves is that the mass of particular grass seeds that was lost from soils was positively correlated with the mass of such seeds in bird diets, and that the main target of bird consumption, i.e. medium-sized grass seeds, suffered the highest postdispersal loss. 6. It is concluded that autumn-winter granivores in the central Monte desert, particularly birds, mainly consume newly produced grass seeds and that they might have major qualitative as well as quantitative impacts on soil-seed reserves.
author López de Casenave, Javier Néstor
author_facet López de Casenave, Javier Néstor
author_sort López de Casenave, Javier Néstor
title Granivore impact on soil-seed reserves in the central Monte desert, Argentina
title_short Granivore impact on soil-seed reserves in the central Monte desert, Argentina
title_full Granivore impact on soil-seed reserves in the central Monte desert, Argentina
title_fullStr Granivore impact on soil-seed reserves in the central Monte desert, Argentina
title_full_unstemmed Granivore impact on soil-seed reserves in the central Monte desert, Argentina
title_sort granivore impact on soil-seed reserves in the central monte desert, argentina
publishDate 1998
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_02698463_v12_n4_p640_Marone
http://hdl.handle.net/20.500.12110/paper_02698463_v12_n4_p640_Marone
work_keys_str_mv AT lopezdecasenavejaviernestor granivoreimpactonsoilseedreservesinthecentralmontedesertargentina
_version_ 1768545689473646592