Artículo

Resumen:

En las últimas dos décadas se generó un debate acerca de la relación entre la diversidad y el funcionamiento ecosistémico. Los pastizales y sus herbívoros proveen uno de los casos de estudio más ampliamente utilizados para analizar esta relación. En los pastizales del Río de la Plata existen evidencias de relaciones positivas y negativas entre la riqueza de especies y la Productividad Primaria Neta Aérea (PPNA). El objetivo de este trabajo fue analizar dicha relación en pastizales naturales pastoreados de la región Centro-Sur de Uruguay. Se utilizaron dos estimadores de la PPNA, el Índice de Vegetación Normalizado (IVN) y la biomasa acumulada. En un ambiente heterogéneo en cuanto a fertilidad del suelo se evaluó la riqueza de especies, el IVN y la biomasa acumulada. El IVN y la biomasa acumulada se relacionaron positivamente con la riqueza. Las gramíneas erectas y las hierbas mostraron los valores más altos para riqueza de especies. Por su parte, las gramíneas postradas con únicamente 4 especies (8% del total) aportaron cerca del 35% de la biomasa total y explicaron gran parte de la productividad de estos pastizales. Este trabajo brinda evidencias a favor de una relación positiva y lineal entre riqueza y productividad primaria.

Abstract:

In the past two decades a considerable debate was generated among ecologists due to differences in the results of experiments which evaluated the relationship between diversity and ecosystem functioning. Recent experimental and theoretical work in this area has also led to animated debates and controversies. A large number of hypotheses linking species richness and ecosystem functioning have been tested. This relationship has been studied primarily through manipulative experiments but little is known about descriptive studies. Grasslands and their grazers provide one of the strongest and widespread cases for studying this relationship. Evidences of both, positive and negative relationships between species richness and Aboveground Net Primary Productivity (ANPP) were founded in the Río de la Plata grasslands. The aim of this paper is to examine the relationship between species richness and ANPP in natural grasslands under continuous grazing of the Southern-Central region of Uruguay. We used two estimators of the ANPP, the Normalized Difference Vegetation Index (NDVI) and the accumulated green biomass. In a heterogeneous environment in terms of soil fertility, species richness and NDVI were measured in 44 plots of 30 cm of diameter. The plots were harvested to estimate the accumulated green biomass and the species were grouped in three Plant Functional Types. The results indicated that both descriptors were positively related to species richness (only the NDVI was signiºcant). Erect grasses and herbs showed higher values for species richness. On the other hand, the prostrate grasses despite being a group with only four species (8% of the total species), contribute with abundant biomass (about 35% of the total biomass) and explain much of the productivity of these grasslands. This paper provides evidence for a linear and positive relationship between species richness and ecosystem functioning descriptors

Registro:

Documento:Publicación periódica
Título:Relación entre la riqueza de especies vegetales y la productividad en pastizales naturales
Título alt:Relationship between plant species richness and productivity in natural grasslands
Autor:López Mársico, Luis; Altesor, Alice
Fecha:2011-04
Titulo revista:Ecología Austral
Editor:Asociación Argentina de Ecología; Argentina.
Handle: http://hdl.handle.net/20.500.12110/ecologiaaustral_v021_n01_p101
Idioma:Español
Palabras clave:funcionamiento ecosistémico; tipos funcionales de plantas; índice de vegetación; normalizado; biomasa acumulada; Uruguay
keywords:ecosystem functioning; plant functional types; normalized difference vegetation index; accumulated biomass; Uruguay
Año:2011
Volumen:021
Número:01
Página de inicio:101
Página de fin:109
Formato:application/pdf
PDF:https://bibliotecadigital.exactas.uba.ar/download/ecologiaaustral/ecologiaaustral_v021_n01_p101.pdf
Registro:https://bibliotecadigital.exactas.uba.ar/collection/ecologiaaustral/document/ecologiaaustral_v021_n01_p101

Citas:

---------- APA ----------
López Mársico, L. & Altesor, A. (2011) . Relationship between plant species richness and productivity in natural grasslands. Ecología Austral, 021 (01) , 101-109.
Recuperado de https://bibliotecadigital.exactas.uba.ar/collection/ecologiaaustral/document/ecologiaaustral_v021_n01_p101 [ ]
---------- CHICAGO ----------
López Mársico, L., Altesor, A. "Relationship between plant species richness and productivity in natural grasslands" . Ecología Austral 021, no. 01 (2011) : 101-109.
Recuperado de https://bibliotecadigital.exactas.uba.ar/collection/ecologiaaustral/document/ecologiaaustral_v021_n01_p101 [ ]
---------- MLA ----------
López Mársico, L., Altesor, A. "Relationship between plant species richness and productivity in natural grasslands" . Ecología Austral, vol. 021, no. 01, 2011, pp. 101-109.
Recuperado de https://bibliotecadigital.exactas.uba.ar/collection/ecologiaaustral/document/ecologiaaustral_v021_n01_p101 [ ]
---------- VANCOUVER ----------
López Mársico, L., Altesor, A. Relationship between plant species richness and productivity in natural grasslands. 2011;021(01):101-109.
Available from: https://bibliotecadigital.exactas.uba.ar/collection/ecologiaaustral/document/ecologiaaustral_v021_n01_p101 [ ]