Species replacement and transitional zones in natural grasslands with subtle environmental gradations
Natalia Vercelli A B D and Ilda Entraigas A CA Instituto de Hidrología de Llanuras ‘Dr Eduardo Jorge Usunoff’, Azul City, Buenos Aires Province, Argentina.
B Consejo Nacional de Investigaciones Científicas y Técnicas, Autonomous City of Buenos Aires, Argentina.
C Comisión de Investigaciones Científicas, La Plata City, Buenos Aires Province, Argentina.
D Corresponding author. Email: nvercelli@ihlla.org.ar
The Rangeland Journal 43(1) 23-33 https://doi.org/10.1071/RJ20043
Submitted: 26 May 2020 Accepted: 22 July 2021 Published: 3 September 2021
Abstract
Heterogeneity creates borders, limits and contrasts between patches. In turn, this pattern generates new processes. Linked to heterogeneity, ecological systems have limits where layout is essential to understanding system organisation. This study analysed internal heterogeneity in natural grassland using: (1) estimation of species replacement in space, and (2) identification of transitional zones and definition of their ecological features in an extremely flat area of the Flooding Pampa, Argentina. Transition analysis was conducted at three sites; 77 plots in total. In each plot, all species, their cover percentage and the proportion of bare soil were recorded and soil samples (0–20 cm depth) measured for pH and electrical conductivity. With floristic data, we explored the relationship between pairwise similarities in community structure and pairwise differences in space, adjusting similarity as a linear or non-linear function of geographical distance. We then conducted a cluster analysis to identify transitional zones, which were associated with large vegetation units described for the Flooding Pampa. Floristic composition in transitional zones was analysed according to the proportions of species and combinations characteristic of the different plant communities. Finally, we synthetised topo-edaphic measured information with a Principal Component Analysis to analyse transitional zone environmental properties. Joining hierarchical classification methods and Indicator Species Analysis for single species and combinations, we highlighted internal heterogeneity, often not noticed in these environments. Rotational livestock grazing contribute to heterogeneity that is typical of these grasslands. Knowledge about transitional zones strongly supports the development of management strategies to prevent grassland degradation.
Keywords: community replacement, ecotones, Flooding Pampa, grasslands, internal heterogeneity.
References
Agnelli, L., Ursino, M., Refi, R., Gregorini, P., Eirin, M., Rodríguez, G. A., and Ansín, O. (2011). Stocking rates effects on performance and ingestive behavior of grazing beef heifers on modified range. In: ‘Proceedings of the IX International Rangeland Congress’. Rosario, Argentina 2.Anderson, M. A., Crist, T. O., Chase, J. M., Vellend, M., Inouye, B. D., Freestone, A. L., Sanders, N. J., Cornell, H. V., Comita, L. S., Davies, K. F., Harrison, S. P., Kraft, N. J. B., Stegen, J. C., and Swenson, N. G. (2011). Navigating the multiple meanings of β diversity: a roadmap for the practicing ecologist. Ecology Letters 14, 19–28.
| Navigating the multiple meanings of β diversity: a roadmap for the practicing ecologist.Crossref | GoogleScholarGoogle Scholar |
Bailey, D. W., Gross, J. E., Laca, E. A., Rittenhouse, L. R., Coughenour, M. B., Swift, D. M., and Sims, P. L. (1996). Mechanisms that result in large herbivore grazing distribution patterns. Journal of Range Management 49, 386–400.
| Mechanisms that result in large herbivore grazing distribution patterns.Crossref | GoogleScholarGoogle Scholar |
Briske, D. D., Fuhlendorf, S. D., and Smeins, F. E. (2003). Vegetation dynamics on rangelands: a critique of the current paradigms. Journal of Applied Ecology 40, 601–614.
| Vegetation dynamics on rangelands: a critique of the current paradigms.Crossref | GoogleScholarGoogle Scholar |
Burkart, S. E., León, R. J. C., Conde, C., and Perelman, S. B. (2011). Plant species diversity in remnant grasslands on arable soils in the cropping Pampa. Plant Ecology 212, 1009–1024.
| Plant species diversity in remnant grasslands on arable soils in the cropping Pampa.Crossref | GoogleScholarGoogle Scholar |
Cadenasso, M. L., Pickett, S. T. A., Weathers, K. C., and Jones, C. G. (2003). A framework for a theory of ecological boundaries. Bioscience 53, 750–758.
| A framework for a theory of ecological boundaries.Crossref | GoogleScholarGoogle Scholar |
Camarero, J. J., and Fortin, M. J. (2006). Detección cuantitativa de fronteras ecológicas y ecotonos. Ecosistemas 15, 76–87.
Chaneton, E. J. (2005). Factores que determinan la heterogeneidad de la comunidad vegetal en diferentes escalas espaciales. In: ‘La heterogeneidad de la vegetación de los agroecosistemas: un homenaje a R.J.C. León’. (Eds M. Oesterheld, M. R. Aguiar, C. M. Ghersa and J. M. Paruelo.) pp. 19–42. (Editorial Facultad de Agronomía, UBA: Buenos Aires.)
Chaneton, E. J., Facelli, J. M., and León, R. J. C. (1988). Floristic changes induced by flooding on grazed and ungrazed lowland grasslands in Argentina. Journal of Range Management 41, 495–499.
| Floristic changes induced by flooding on grazed and ungrazed lowland grasslands in Argentina.Crossref | GoogleScholarGoogle Scholar |
Chaneton, E. J., Perelman, S. B., Omacini, M., and León, R. J. C. (2002). Grazing, environmental heterogeneity, and alien plant invasions in temperate pampa grasslands. Biological Invasions 4, 7–24.
| Grazing, environmental heterogeneity, and alien plant invasions in temperate pampa grasslands.Crossref | GoogleScholarGoogle Scholar |
Danz, N. P., Frelich, L. E., Reich, P. B., and Niemi, G. J. (2013). Do vegetation boundaries display smooth or abrupt spatial transitions along environmental gradients? Evidence from the prairie–forest biome boundary of historic Minnesota, USA. Journal of Vegetation Science 24, 1129–1140.
| Do vegetation boundaries display smooth or abrupt spatial transitions along environmental gradients? Evidence from the prairie–forest biome boundary of historic Minnesota, USA.Crossref | GoogleScholarGoogle Scholar |
De Cáceres, M., and Legendre, P. (2009). Associations between species and groups of sites: indices and statistical inference. Ecology 90, 3566–3574.
| Associations between species and groups of sites: indices and statistical inference.Crossref | GoogleScholarGoogle Scholar | 20120823PubMed |
De Cáceres, M., Legendre, P., and Moretti, M. (2010). Improving indicator species analysis by combining groups of sites. Oikos 119, 1674–1684.
| Improving indicator species analysis by combining groups of sites.Crossref | GoogleScholarGoogle Scholar |
De Cáceres, M., Legendre, P., Wiser, S., and Brotons, L. (2012). Using species combinations in indicator value analyses. Methods in Ecology and Evolution 3, 973–982.
| Using species combinations in indicator value analyses.Crossref | GoogleScholarGoogle Scholar |
De Cáceres, M., Jansen, F., and Dell, N. (2020). R package “indicspecies” – Relationship between species and group of sites. Version 1.7.9. Available at: https://CRAN.R-project.org/package=indicspecies (accessed 1 May 2020).
Di Castri, F., Hansen, A. J., and Holland, M. M. (1988). A new look at ecotones: emerging international projects on landscape boundaries. Biological International 17, 1–163.
Dufrene, M., and Legendre, P. (1997). Species assemblages and indicator species: the need for a flexible asymmetrical approach. Ecological Monographs 67, 345–366.
| Species assemblages and indicator species: the need for a flexible asymmetrical approach.Crossref | GoogleScholarGoogle Scholar |
Entraigas, I., Vercelli, N., Ares, M. G., Varni, M., and Zeme, S. (2017). Flooding effects on grassland species composition in the Azul creek basin, Argentina. The Rangeland Journal 39, 245–252.
| Flooding effects on grassland species composition in the Azul creek basin, Argentina.Crossref | GoogleScholarGoogle Scholar |
Entraigas, I., Vercelli, N., and Fajardo, L. (2019). Plant communities along preferential superficial water flow paths across a floodplain landscape. Ecohydrology 12, e2124.
| Plant communities along preferential superficial water flow paths across a floodplain landscape.Crossref | GoogleScholarGoogle Scholar |
Erdős, L., Krstonösić, D., János Kiss, P., Bátori, Z., Tölgyesi, C., and Ŝkvorc, Z. (2019). Plant composition and diversity at edges in a semi-natural forest–grassland mosaic. Plant Ecology 220, 279–292.
| Plant composition and diversity at edges in a semi-natural forest–grassland mosaic.Crossref | GoogleScholarGoogle Scholar |
Farina, A. (2006). ‘Principles and methods in landscape ecology – Toward a Science of Landscape.’ (Springer: The Netherlands.)
Forman, R. T. T., and Moore, P. N. (1992). Theoretical foundations for understanding boundaries in landscape mosaics. In: ‘Landscape Boundaries: Consequences for Biotic Diversity and Ecological Flows. Ecological Studies (Analysis and Synthesis)’. Vol. 92. (Eds A. J. Hansen and F. Di Castri.) (Springer: New York.)
Frelich, L., Calcote, R., Davis, M., and Pastor, J. (1993). Patch formation and maintenance in an old-growth hemlock-hardwood forest. Ecology 74, 513–527.
| Patch formation and maintenance in an old-growth hemlock-hardwood forest.Crossref | GoogleScholarGoogle Scholar |
Fuhlendorf, S. D., and Engle, D. M. (2001). Restoring heterogeneity on rangelands: ecosystem management based on evolutionary grazing patterns. Bioscience 51, 625–632.
| Restoring heterogeneity on rangelands: ecosystem management based on evolutionary grazing patterns.Crossref | GoogleScholarGoogle Scholar |
Fuhlendorf, S. D., and Engle, D. M. (2004). Application of the fire-grazing interaction to restore a shifting mosaic on tallgrass prairie. Journal of Applied Ecology 41, 604–614.
| Application of the fire-grazing interaction to restore a shifting mosaic on tallgrass prairie.Crossref | GoogleScholarGoogle Scholar |
Fuhlendorf, S. D., Townsend, D. E., Elmore, R. D., and Engle, D. M. (2010). Pyric-herbivory to promote rangeland heterogeneity: evidence from small mammal communities. Rangeland Ecology and Management 63, 670–678.
| Pyric-herbivory to promote rangeland heterogeneity: evidence from small mammal communities.Crossref | GoogleScholarGoogle Scholar |
Fuschini Mejía, M. C. (1994). El agua en las llanuras. Programa Hidrológico Internacional. UNESCO, Montevideo.
Fynn, R. S. W. (2012). Functional resource heterogeneity increases livestock and rangeland productivity. Rangeland Ecology and Management 65, 319–329.
| Functional resource heterogeneity increases livestock and rangeland productivity.Crossref | GoogleScholarGoogle Scholar |
Hufkens, K., Scheunders, P., and Ceulemans, R. (2009). Ecotones in vegetation ecology: methodologies and definitions revisited. Ecological Research 24, 977–986.
| Ecotones in vegetation ecology: methodologies and definitions revisited.Crossref | GoogleScholarGoogle Scholar |
Hurtado, M. A., Moscatelli, G. N., and Godagnone, R. E. (2005). Los suelos de la provincia de Buenos Aires. In: ‘Geología y Recursos Minerales de la Provincia de Buenos Aires’. (Eds R. E. de Barrio, R. O. Etcheverry, M. F. Caballé and E. Llambías.) pp. 201–218. (Relatorio del XVI Congreso Geológico Argentino: La Plata.)
Imbellone, P., Giménez, J. E., and Panigatti, J. L. (2010). ‘Suelos de la Región Pampeana. Procesos de Formación.’ (Ediciones INTA: Buenos Aires.)
INTA (1992). ‘Cartas de Suelos de la República Argentina, Provincia de Buenos Aires (1:50.000)’. Hojas 3760-10 y 3760-16. (Instituto de Suelos. Centro de Investigaciones en Recursos Naturales. Ediciones INTA, Buenos Aires.)
IPCC (2014). ‘Climate Change 2014: Impacts, Adaptations and Vulnerability. Summary for Policymakers.’ (Cambridge University Press: Cambridge, UK.)
Joyce, C. B., Simpson, M., and Casanova, M. (2016). Future wet grasslands: ecological implications of climate change (Special Feature: Wetlands and global climate and land-use change.). Ecosystem Health and Sustainability 2, e01240.
| Future wet grasslands: ecological implications of climate change (Special Feature: Wetlands and global climate and land-use change.).Crossref | GoogleScholarGoogle Scholar |
Kandus, P., Quintana, R. D., Minotti, P. G., Oddi, J., Baigún, C., González Trilla, G., and Ceballo, D. (2011). Ecosistemas de humedal y una perspectiva hidrogeomórfica como marco para la valoración ecológica de sus bienes y servicios. In: ‘Valoración de servicios ecosistémicos: conceptos, herramientas y aplicaciones para el ordenamiento territorial’. (Eds P. Laterra, E. G. Jobbágy and J. M. Paruelo.) pp. 264–290. (Ediciones INTA: Buenos Aires.)
Lanceta, M., Entraigas, I., de Dominicis, H., and Vercelli, N. (2016). Determinación de la superficie potencial ganadera a través del uso de sistemas de información geográfica. Geofocus 18, 47–63.
Matteucci, S. D. (2012). Ecorregión Pampa. In: ‘Ecorregiones y Complejos Ecosistémicos Argentinos’. (Eds J. Morello, S. D. Matteucci, A. F. Rodríguez and M. Silva.) pp. 391–445. (Orientación Gráfica Editora: Buenos Aires.)
McKinney, M. L., and Lockwood, J. L. (1999). Biotic homogenization: a few winners replacing many losers in the next mass extinction. Trends in Ecology & Evolution 14, 450–453.
| Biotic homogenization: a few winners replacing many losers in the next mass extinction.Crossref | GoogleScholarGoogle Scholar |
Mueller-Dombois, D., and Ellenberg, H. (1974). ‘Aims and Methods of Vegetation Ecology.’ (John Wiley and Sons: New York.)
Pacala, S. W., and Levin, S. A. (1997). Biologically generated spatial pattern and the coexistence of competing species. In: ‘Spatial Ecology: The Role of Space in Population Dynamics and Interspecific Interactions’. (Eds D. Tilman and P. Kareiva.) pp. 204–232. (Princeton University Press: Princeton, NJ, USA.)
Perelman, S. B., León, R. J. C., and Oesterheld, M. (2001). Cross-scale vegetation patterns of Flooding Pampa grasslands. Journal of Ecology 89, 562–577.
| Cross-scale vegetation patterns of Flooding Pampa grasslands.Crossref | GoogleScholarGoogle Scholar |
R Core Team (2020). R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. Available at: https://www.r-project.org/ (accessed 1 May 2020).
Reed, D. N., Anderson, T. M., Dempewolf, J., Metzger, K. L., and Serneels, S. (2009). The spatial distribution of vegetation types in the Serengeti ecosystem: the influence of rainfall and topographic relief on vegetation patch characteristics. Journal of Biogeography 36, 770–782.
| The spatial distribution of vegetation types in the Serengeti ecosystem: the influence of rainfall and topographic relief on vegetation patch characteristics.Crossref | GoogleScholarGoogle Scholar |
Sala, O. E., Oesterheld, M., León, R. J. C., and Soriano, A. (1986). Grazing effects upon plant community structure in subhumid grasslands of Argentina. Vegetatio 67, 27–32.
Shmida, A., and Wilson, M. V. (1985). Biological determinants of species diversity. Journal of Biogeography 12, 1–20.
| Biological determinants of species diversity.Crossref | GoogleScholarGoogle Scholar |
Smith, T. B., Wayne, R. K., Girman, D. J., and Bruford, M. W. (1997). A role for ecotones in generating rainforest biodiversity. Science 276, 1855–1857.
| A role for ecotones in generating rainforest biodiversity.Crossref | GoogleScholarGoogle Scholar |
Soininen, J., McDonald, R., and Hillebrand, H. (2007). The distance decay of similarity in ecological communities. Ecography 30, 3–12.
| The distance decay of similarity in ecological communities.Crossref | GoogleScholarGoogle Scholar |
Sørensen, T. (1948). A method of establishing groups of equal amplitude in plant sociology based on similarity of species and its application to analyses of the vegetation on Danish commons. Biologiske Skrifter / Kongelige Danske Videnskabernes Selskab 5, 1–34.
SSSA – ASA (1996). ‘Methods of Soil Analysis. Part 3 ‐ Chemical Methods.’ Soil Science Society of America Book Series No. 5. (SSSI: Madison, WI, USA.)
Taboada, M. A., Damiano, F., and Lavado, R. S. (2009). Inundaciones en la Región Pampeana. Consecuencias sobre los suelos. In: ‘Alteraciones de la fertilidad de los suelos. El halomorfismo, la acidez, el hidromorfismo y las inundaciones’. (Eds M. A. Taboada and R. S. Lavado.) pp. 103–127. (Editorial Facultad de Agronomía de la UBA, Buenos Aires.)
Teague, W. R., Dowhower, S. L., and Waggoner, J. A. (2004). Drought and grazing patch dynamics under different grazing management. Journal of Arid Environments 58, 97–117.
| Drought and grazing patch dynamics under different grazing management.Crossref | GoogleScholarGoogle Scholar |
Thiers, B. (2020). Index Herbariorum: a global directory of public herbaria and associated staff. New York Botanical Garden’s Virtual Herbarium. Available at: http://sweetgum.nybg.org/ih (accessed 1 May 2020)
Timm, N. H. (2002). ‘Applied Multivariate Analysis.’ Springer Texts in Statistics. (Springer: Berlin Heidelberg, New York.)
Tuomisto, H., Ruokolainen, K., and Yli-Halla, M. (2003). Dispersal, environment, and floristic variation of western Amazonian forests. Science 299, 241–244.
| Dispersal, environment, and floristic variation of western Amazonian forests.Crossref | GoogleScholarGoogle Scholar | 12522248PubMed |
Turner, M. G., Gardner, R. H., and O’Neill, R. V. (2001). ‘Landscape Ecology in Theory and Practice: Pattern and Process.’ (Springer: New York.)
Vecchio, M. A., Bolaños, V. R. A., Golluscio, R. A., and Rodríguez, A. M. (2019). Rotational grazing and exclosure improves grassland condition of the halophytic steppe in Flooding Pampa (Argentina) compared with continuous grazing. The Rangeland Journal 41, 1–12.
| Rotational grazing and exclosure improves grassland condition of the halophytic steppe in Flooding Pampa (Argentina) compared with continuous grazing.Crossref | GoogleScholarGoogle Scholar |
Vercelli, N. (2018). Heterogeneidad del paisaje en la cuenca inferior del arroyo del Azul, provincial de Buenos Aires. Doctoral Thesis, Universidad Nacional de Mar del Plata, Argentina.
Vercelli, N., Varni, M., Lara, B., Entraigas, I., and Ares, G. (2020). Linking soil water balance with flood spatial arrangement in an extremely flat landscape. Hydrological Processes 34, 21–32.
| Linking soil water balance with flood spatial arrangement in an extremely flat landscape.Crossref | GoogleScholarGoogle Scholar |
Ward, R. D., Burnside, N. G., Joyce, C. B., and Sepp, K. (2013). The use of medium point density LiDAR elevation data to determine plant community types in Baltic coastal wetlands. Ecological Indicators 33, 96–104.
| The use of medium point density LiDAR elevation data to determine plant community types in Baltic coastal wetlands.Crossref | GoogleScholarGoogle Scholar |
Wedin, D. A., and Tilman, D. (1990). Species effects on nitrogen cycling: a test with perennial grasses. Oecologia 84, 433–441.
| Species effects on nitrogen cycling: a test with perennial grasses.Crossref | GoogleScholarGoogle Scholar | 28312957PubMed |
Wiens, J. A. (1989). Spatial scaling in ecology. Functional Ecology 3, 385–397.
| Spatial scaling in ecology.Crossref | GoogleScholarGoogle Scholar |
Zárate, M. A., and Mehl, A. (2010). Geología y geomorfología de la cuenca del arroyo del Azul, provincia de Buenos Aires, Argentina. In: ‘Hacia la gestión integral de los recursos hídricos en zonas de llanura’. Vol. I. (Eds M. Varni, I. Entraigas and L. Vives.) pp. 65–78. (Editorial Martín: Mar del Plata.)
Zuloaga, F. O., and Morrone, O. (1996). Catálogo de las plantas vasculares de la Argentina: Pteridophyta, Gymnospermae y Monocotyledoneae (excluyendo Poaceae). Monographs in Systematic Botany from the Missouri Botanical Garden 60, 1–332.
Zuloaga, F. O., and Morrone, O. (1999). Catálogo de las Plantas Vasculares de la Argentina: Dicotyledoneae. Monographs in Systematic Botany from the Missouri Botanical Garden 74, 1–1246.
Zuloaga, F. O., Morrone, O., and Belgrano, J. M. (2008). Catálogo de las plantas vasculares del Cono Sur (Argentina, sur de Brasil, Chile, Paraguay, y Uruguay). Vol. 1 Pteridophyta, Gymnospermae y Monocotyledoneae. Monographs in Systematic Botany from the Missouri Botanical Garden 107, 1–983.
Zuloaga, F. O., Belgrano, J. M., and Zanotti, C. (2019). Actualización del Catálogo de las Plantas Vasculares del Cono Sur. Darwiniana 7, 208–278.
| Actualización del Catálogo de las Plantas Vasculares del Cono Sur.Crossref | GoogleScholarGoogle Scholar |