Abstract
Grazing not only modifies the structure and functioning of grasslands, it also changes micro-environmental conditions that alter the availability of resources. The aim of this study was to analyze the response of grasses with different photosynthetic pathways (C3/C4), growth forms (prostrate/erect), and grazing responses (increaser/decreaser) to defoliation and resource availability. In a greenhouse, we performed a factorial experiment with three factors: defoliation, light, and water and three species: Axonopus affinis (C4 prostrate, increaser), Coelorachis selloana (C4 erect, decreaser), and Bromus auleticus (C3 erect, decreaser). We measured the relative growth rate (RGR), biomass assignment, and specific leaf area. The RGR of both C4 species was affected by light availability, while the decreaser C3 did not respond to any factor. Biomass allocation to leaves and stolons changed with the interaction between light and water in the C4 prostrate species (increaser). In the C4 erect grass (decreaser), biomass allocation was more affected by defoliation under low levels of light and water. Low light availability and defoliation reduced the assignment to leaves, while the allocation to rhizomes increased. Species-specific responses to resources availability that are modified by grazing were related to photosynthetic pathway, growth form, and grazing responses. Biomass allocation was related to strategies to avoid and/or tolerate grazing. The investment to leaves was limited by light and water availability in prostrate species, while in erect grasses it was controlled by defoliation and water availability. Our results highlight the importance of species responses to changes in resource availability associated to grazing regimes.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Aguiar MR, Paruelo JM, Sala OE, Lauenroth WK (1996) Ecosystem responses to changes in plant functional type composition: an example from the Patagonian steppe. J Veg Sci 7:381–390
Altesor A, Pezzani F, Grun S, Rodríguez C (1999) Relationship between spatial strategies and life-history attributes in a Uruguayan grassland: a functional approach. J Veg Sci 10:457–462
Altesor A, Oesterheld M, Leoni E, Lezama F, Rodríguez C (2005) Effect of grazing on community structure and productivity of a Uruguayan grassland. Plant Ecol 179:83–91
Altesor A, Pi��eiro G, Lezama F, Jackson RB, Sarasola M, Paruelo JM (2006) Ecosystem changes associated with grazing removal in sub-humid grasslands of South America. J Veg Sci 17:323–332
Bagnato C (2010) Consecuencias de la heterogeneidad de la vegetación en la dinámica del agua en el suelo: Contrastes entre una estepa semiárida y un pastizal subhúmedo. Dissertation, Universidad de Buenos Aires
Boardman NK (1977) Comparative photosynthesis of sun and shade plants. Annu Rev Plant Phys 28:355–377
Carlucci MB, Streit H, Duarte LDS, Pillar VD (2012) Individual-based trait analyses reveal assembly patterns in tree sapling communities. J Veg Sci 23:176–186
Cayssials V (2010) Relación entre atributos de las gramíneas nativas de pastizales uruguayos y el ambiente: efectos del hábitat y del pastoreo. Master Thesis. Dissertation, Universidad de la República
Cingolani AM, Posse G, Collantes MB (2005) Plant functional traits, herbivore selectivity and response to sheep grazing in Patagonian steppe grasslands. J Appl Ecol 42:50–59
Coughenour MB (1985) Graminoid responses to grazing by large herbivores: adaptations, exaptations, and interacting processes. Ann Mo Bot Gard 72:852–863
Díaz S, Acosta A, Cabido M (1992) Morphological analysis of herbaceous communities under different grazing regimes. J Veg Sci 3:689–696
Dyksterhuis EJ (1949) Condition and management of rangeland based on quantitative ecology. J Range Manag 2:104–115
Evans JR, Poorter H (2001) Photosynthetic acclimation of plants to growth irradiance: the relative importance of specific leaf area and nitrogen partitioning in maximizing carbon gain. Plant Cell Environ 24:755–767
Facelli JM (1988) Response to grazing after nine years of cattle exclusion in a Flooding Pampa grassland, Argentina. Vegetatio 78:21–25
Fahnestock JT, Knapp AK (1994) Plant responses to selective grazing by bison: interactions between light, herbivory and water stress. Vegetatio 115:123–131
Fernández G, Texeira M, Altesor A (2014) The small scale spatial pattern of C3 and C4 grasses depends on shrub distribution. Austral Ecol 39:532–539
Ferraro DO, Oesterheld M (2002) Effect of defoliation on grass growth. A quantitative review. Oikos 98:125–133
Gautreau P (2013) Forestación, territorio y ambiente: 25 años de silvicultura transnacional em Uruguay, Brasil y Argentina. Trilce, Montevideo
Hobbs NT, Baker DL, Bear GD, Bowden DC (1996) Ungulate grazing in sagebrush grassland: mechanisms of resource competition. Ecol Appl 6:200–217
Hoffmann WA, Poorter H (2002) Avoiding bias in calculations of relative growth rate. Ann Bot 90:37–42
Konings H (1989) Physiological and morphological differences between plants with a high NAR or a high LAR as related to environmental conditions. In: Lambers H, Cambridge ML, Konings H, Pons TL (eds) Causes and consequences of variation in growth rate and productivity of higher plants. SPB Academic Publishing, The Hague, pp 101–123
Lavado RS, Sierra JO, Hashimoto PN (1995) Impact of grazing on soil nutrients in a Pampean grassland. J Range Manag 49:452–457
Lavorel S, Garnier E (2002) Predicting changes in community composition and ecosystem functioning from plant traits: revisiting the Holy Grail. Funct Ecol 16:545–556
Leoni E, Altesor A, Paruelo JM (2009) Explaining patterns of primary production from individual level traits. J Veg Sci 20:612–619
Lezama F, Baeza S, Altesor A, Cesa A, Chaneton EJ, Paruelo JM (2014) Variation of grazing-induced vegetation changes across a large-scale productivity gradient. J Veg Sci 25:8–21
McNaughton SJ (1979) Grazing as an optimization process: grass-ungulate relationships in the Serengeti. Am Nat 113:691–703
McNaughton SJ (1983) Compensatory plant growth as a response to herbivory. Oikos 40:329–336
McNaughton SJ (1985) Ecology of a grazing ecosystem: the Serengeti. Ecol Monogr 55:259–294
Meyer GA (1998) Pattern of defoliation and its effects on photosynthesis and growth of Goldenrod. Funct Ecol 12:270–279
Milchunas DG, Lauenroth WK (1993) A quantitative assessment of the effects of grazing on vegetation and soils over a global range of environments. Ecol Monogr 63:327–366
Milchunas DG, Sala OE, Lauenroth WK (1988) A generalized model of the effects of grazing by large herbivores on grassland community structure. Am Nat 132:87–105
Nowak RS, Caldwell MM (1984) A test of compensatory photosynthesis in the field: implications for herbivory tolerance. Oecologia 61:311–318
Noy-Meir I, Gutman M, Kaplan Y (1989) Responses of Mediterranean grassland plants to grazing and protection. J Ecol 77:290–310
Oesterheld M, Loreti J, Semmartin M, Paruelo JM (1999) Grazing, fire, and climate effects on primary productivity of grasslands and savannas. In: Walker L (ed) Ecosystems of disturbed ground. Elsevier Science, Oxford, pp 287–306
Paruelo JM, Guerschman JP, Piñeiro G, Jobbágy EG, Verón SR, Baldi G, Baeza S (2006) Cambios en el uso de la tierra en Argentina y Uruguay: marcos conceptuales para su análisis. Agrociencia 10:47–61
Paruelo JM, Piñeiro G, Baldi G, Baeza S, Lezama F, Altesor A, Oesterheld M (2010) Carbon stocks and fluxes in rangelands of the Río de la Plata Basin. Rangel Ecol Manag 63:89–108
Piñeiro G, Paruelo JM, Jobbágy EG, Jackson RD, Oesterheld M (2009) Grazing effects on belowground C and N stocks along a network of cattle exclosures in temperate and subtropical grasslands of South America. Glob Biogeochem Cycles 23(2):GB2003
Poorter H, Garnier E (1996) Plant growth analysis: an evaluation of experimental design and computational methods. J Exp Bot 47:1343–1351
Poorter H, Nagel O (2000) The role of biomass allocation in the growth response of plants to different levels of light, CO2, nutrients and water: a quantitative review. Aust J Plant Physiol 27:595–607
Poorter H, Niinemets Ü, Poorter L, Wright I, Villar R (2009) Causes and consequences of variation in leaf mass per area (LMA): a meta-analysis. New Phytol 182:565–588
Proulx M, Mazumder A (1998) Reversal of grazing impact on plant species richness in nutrient-poor vs. nutrient-rich ecosystems. Ecology 79:2581–2592
Reich PB, Walters MB, Ellsworth DS (1997) From tropics to tundra: global convergence in plant functioning. Proc Natl Acad Sci USA 94:13730–13734
Rodríguez C, Leoni E, Lezama F, Altesor A (2003) Temporal trends in species composition and plant traits in natural grasslands of Uruguay. J Veg Sci 14:433–440
Sala OE (1988) The effect of herbivory on vegetation structure. In: Werger MJA, van der Aart PJM, During HJ, Verboeven JTA (eds) Plant form and vegetation structure. SPB, The Hague, pp 317–330
Sala OE (2001) Temperate grasslands. In: Chapin FS III, Sala OE, Huber-Sannwald E (eds) Global biodiversity in a changing environment, ecological studies 152. Springer, Berlin, pp 121–137
Schlesinger WH, Reynolds JF, Cunningham GL, Huenneke LF, Jarrell WM, Virginia RA, Whitford WG (1990) Biological feedbacks in global desertification. Science 247:1043–1048
Soriano A (1991) Río de la Plata grasslands. In: Coupland RT (ed) Natural grasslands: introduction and western hemisphere. Elsevier, Amsterdam, pp 367–407
Suding KN, Lavorel S, Chapin FS III, Cornelissen JHC, Diaz S, Garnier E, Goldberg D, Hooper D, Jackson ST, Navas ML (2008) Scaling environmental change through the community-level: a trait-based response-and-effect framework for plants. Glob Change Biol 14:1125–1140
Taboada MA, Lavado RS (1988) Grazing effects on the bulk density in a Natraquoll of the flooding Pampa of Argentina. J Range Manag 41:500–503
Whicker A, Detling J (1988) Ecological consequences of prairie dog disturbance. Bioscience 38:778–785
Acknowledgments
This work was carried out with the aid of a grant from the Inter-American Institute for Global Change Research (IAI) CRN3095, which is supported by the US National Science Foundation (Grant GEO-1128040). We thank the comments and help provided by the members of the Grupo de Ecología de Pastizales (FCIEN-UDELAR) and two anonymous reviewers, which significantly improved an early version of the manuscript.
Author information
Authors and Affiliations
Corresponding author
Additional information
Communicated by Marjan Jongen.
Electronic supplementary material
Below is the link to the electronic supplementary material.
Rights and permissions
About this article
Cite this article
Altesor, A., Leoni, E., Guido, A. et al. Differential responses of three grasses to defoliation, water and light availability. Plant Ecol 218, 95–104 (2017). https://doi.org/10.1007/s11258-016-0669-7
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11258-016-0669-7