Get reliable rangeland science

Fragmentation Status of Tall-Tussock Grassland Relicts in the Flooding Pampa, Argentina
Author
Herrera, Lorena P.
Laterra, Pedo
Maceira, Néstor O.
Zelaya, Karina D.
Martínez, Gustavo A.
Publisher
Society for Range Management
Publication Year
2009-01-01
Body

Since European settlement vast areas of the tall tussock grassland dominated by Paspalum quadrifarium Lam. and Paspalum exaltatum J. Presl (‘‘pajonal’’ grassland) in the Flooding Pampa of Argentina were converted to croplands and short grasslands. With the use of Landsat satellite images, we analyzed current (1998-2000) cover and spatial integrity of the pajonal community, and compared it with a vegetation map made 50 yr ago (1956-1960). Six categories of land cover were adopted: crops, sown pastures, short grassland, pajonal, wetlands, and anthropogenic areas. With the use of metrics from FRAGSTATS, landscape pattern and composition were analyzed at two scales: 1) regionally, by comparing two edaphic domain areas with relatively low and high restrictions for agriculture (low-restriction domain [LRD] and high-restriction domain [HRD], respectively); and 2) at landscape scale, by comparing ten 22 500-ha randomly selected areas (landscapes) within each edaphic domain. Current relative cover of pajonal grassland (2 173 600 ha) was 32.5%, and similar values were obtained within each edaphic domain. However, the number of pajonal patches was higher and their mean patch size, the Euclidean nearest-neighbor distance among patches (degree of isolation), and their border regularity were lower in the LRD than in the HRD. At landscape scale, the mean size of pajonal patches diminished with the percent of agricultural land within both edaphic domains. The isolation among pajonal patches increased with percent of agricultural land in the HRD, whereas no relationship between the isolation of pajonal patches and percent of agriculture was found in the LRD. As suggested by comparison with past vegetation, current pajonal status mostly results from replacement of pajonal grassland by short grassland types, cultivated pastures, and annual crops (52% and 44% of previously occupied areas in LRD and HRD, respectively), but some expansion of pajonal grassland was also observed (10% and 4% of previously unoccupied areas in LRD and HRD, respectively).  The Rangeland Ecology & Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact lbry-journals@email.arizona.edu for further information. Migrated from OJS platform August 2020

Language
en
Resource Type
Text
Document Type
Journal Issue/Article
Digital Object Identifier (DOI)
10.2111/08-015
Additional Information
Herrera, L. P., Laterra, P., Maceira, N. O., Zelaya, K. D., & Martínez, G. A. (2009). Fragmentation status of tall-tussock grassland relicts in the Flooding Pampa, Argentina. Rangeland Ecology & Management, 62(1), 73-82.
ISSN
0022-409X
OAI Identifier
oai:repository.arizona.edu:10150/643006
Journal Volume
62
Journal Number
1
Journal Pages
73-82
Collection
Rangeland Ecology & Management (REM)
Journal Name
Rangeland Ecology & Management
Keywords
flooding pampa
FRAGSTATS
Landsat Thematic Mapper
landscapes
land-use classification
Paspalum quadrifarium