Julio M. Alcantara RESEARCH

Current Projects

COEXMED-II

Keywords:

ecological networks, forest plant community, plant-plant interactions, mycorrhizal fungi, epibiontic communities on plants, plant community phylogenetics, functional trait complementarity

Summary

In project COEXMED-I we explored two mechanisms of coexistence of woody plants: intransitiviy of the interactions between adult plants and the saplings recruiting under their crown (replacement networks) and negatively density-dependent recruitment (NDD). Our results suggest that both mechanisms operate in mixed pine-oak forests of Southern Spain. But these results are based on the analysis of patterns. To understand the origin of such patterns, in this project we will explore the mechanisms that may cause the intransitive structure of replacement networks and the NDD distribution of saplings. To this end we will address three mechanisms that may affect the adult-recruit interaction: adult-recruit competition, plant-mycorrhizal fungi mutualism and plant-antagonist interactions. Thus, our working hypothesis states that the establishment of adult-recruit interactions depends both on functional traits of the interacting species and on the outcomes of interactions between plants and mutualists (mycorrhizal fungi) and antagonists (pathogenic fungi and insect pests).

We will address this hypothesis through three general objectives: (1) Ascertaining the functional plant traits complementary between adult and recruits; (2) Analysing the plant-mycorrhizal fungi networks; and (3) Estimating the interaction network between plants and their antagonistic fungi and insects.

The broad spectrum of interactions that will be addressed requires the coordination of researchers from 5 institutions, coordinated by the University of Jaén and Estación Experimental del Zaidín (CSIC-Granada). Our group at the University of Jaén, in collaboration with Estación Biológica de Doñana (CSIC-Sevilla), will focus on trait complementarity and antagonistic interactions. The group at Estación Experimental del Zaidín (CSIC-Granada) will collaborate with the Instituto de Ciencias Agrarias (CSIC-Madrid) and Institute National de la Recherche Agronomique (Nancy-France) in the study of endo- and ecto-mycorrhizal fungi. Both plant trait complementarity, antagonistic interactions and mutualistic fungi will be studied in the same set of 50 woody plant species and in the same localities, so we will be able to combine directly these three types of information.

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What are Replacement Networks (RNs)?

Briefly, most theoretical models (from Buffon in the 18^th century to S. P. Hubbell in the 21^st) conceive plant community dynamics as a process of replacement whereby the death of one plant (which we call the canopy plant) releases space where individuals of the same or a different species (the recruit species) can grow, eventually replacing the dead plant. This process of recruitment and replacement can be seen as a basic principle in plant community dynamics. Unfortunately, most often we cannot observe replacement events directly because the process is extremely slow (particularly when it involves woody plants). However, we can assume that the replacing species will be one of those that are able to recruit under established plants. In this way, recruitment is the focus in empirical studies of RNs, and canopy-recruit interactions represent which species recruits under which others (in the qualitative version of RNs), and how likely or how often (in the quantitative version). The set of canopy-recruit interactions that are realized in a local assemblage can be rendered as an interactions network, which we call the replacement network (Fig. 1). The matrix behind RNs can be used in models of plant community dynamics, providing a direct way of feeding theoretical models with empirical data.

Figure 1. Example of the different representations of a replacement network.

A) Weighted matrix corresponding to the quantitative version of the RN. Matrix representations are the basis for estimation of network descriptors. Since RNs are unipartite networks, each species is listed both in the rows and in the columns, and species are arranged in in the same order (alphabetical in this example) in rows and columns. The weighted matrix is the basis for weigthed network descriptors since it includes the information on the frequency of each interaction (fij).

B) The adjacency matrix is the binary (qualitative) form of the RN. It indicates only whether an interaction was realized (black cells) or was absent (white cells). The adjacency matrix is the basis for unweighted network descriptors.

C) Replacement Network directed graph. Nodes represent species and arrows point from the recruit to the canopy species. In this example we have represented the network according to its functional structure, consisting in this case in a large core of species (identified as the largest Strongly Connected Component of the network) and six satellite species (which recruit under core species but do not allow recruitment of core species under their canopy). Self loops indicate recruitment under conspecifics.

Funded by:

- Programa Estatal de Fomento de la Investigación Científica y Técnica de Excelencia

Ministerio de Economía y Competitividad. Spain.

- FEDER funds from the EU

Past Projects

COEXMED-I.- Coexistence of woody plants in Mediterranean forests: intransitive interactions and negative density dependence in recruitment dynamics. 2013-2015.

Functional Structure of Interaction Networks.

Modelling replacement dynamics and disturbance in woody plant communities.

COEXMED-I

Keywords:

Recruitment, Community dynamics, Replacement networks, Mixed forests, Seed dispersal, Seed predation, Plan-plant interactions, Facilitation, Competition, Intransitive interactions, Density dependence.

Summary

Understanding the diversity of plants, the factors determining the number of species in a community and the mechanisms behind their long-term coexistence, is a prominent objective of ecology (Silvertown 2004). According to Chesson (2000) the mechanisms of species coexistence in a community can be classified in two general classes: equalizing mechanisms that decrease fitness differences among species, delaying competitive exclusion, and stabilizing mechanisms that increase the fitness of a species when it becomes rare and decreases it when the species becomes dominant. The project addresses two of such coexistence mechanisms in Mediterranean forests: intransitivity of interactions occurring during the recruitment of new individuals into the community (an equalizing mechanism) and negative density dependent mortality during recruitment (a stabilizing mechanism). To this end, we will study the existence of intransitive interactions in the structure of replacement networks (networks representing the recruitment of individuals of a given species under the canopy of con- or hetero-specific individuals), the probability of replacement of dead plants by recruits of the same or a different species, and the existence of negatively density dependent effects of conspecific and heterospecific plants on sapling growth and surivival. The study focuses in the mixed forests of pines (Pinus halepensis, P, pinaster or P. nigra) and deciduous oaks (Quercus faginea or Q. pyrenaica) from southern Iberian peninsula. Mixed forests in this region harbor a high diversity of woody species, with up to 17 species recorded in 0.25 Ha. This type of forests were much more common in the region during the moister periods of the Holocene, but climatic aridification and human activities during the last millennia have restricted them to small remnants in the interior valleys of the Betic mountains.

Silvertown, J. 2004. Plant coexistence and the niche. Trends Ecol. Evol. 19:605-611

Chesson, P. 2000. Mechanisms of maintenance of species diversity. Annu Rev Ecol Syst 31: 34366.

Funded by:

- Programa Nacional de Proyectos de Investigación Fundamental.

Ministerio de Economía y Competitividad. Spain.

- FEDER funds from the EU

Keywords:

Ecological networks, Network topology, Modularity, Stability, Complexity, Replacement networks, Intransitive interactions, Graph Theory.

Summary

Models describing the dynamics of complex ecological communities share one important component: a matrix describing which species interact with which others and how. The parameters of interaction matrices determine the dynamic properties of these models (e.g. species coexistence, temporal changes in abundance or responses to disturbance), but estimating these parameters from real communities is frequently daunting, if not impossible. Fortunately, some dynamic properties depend only on the structure of the interactions matrix (i.e. on which species interact with which others). We are exploring the concept of Strongly Connected Components (SCCs), that only requires knowledge of the structure of the interaction matrix, and how it can be used to decipher relationships between structure, function and dynamics of complex ecological systems (Alcántara and Rey, 2012, 2014). We focus this research line in models of plant communities driven by the replacement of individuals (replacement networks), but the framework can be applied to other ecological systems like food webs.

Alcántara & Rey. 2012. Linking topological structure and dynamics in ecological networks. American Naturalist 180: 186-199

Alcántara & Rey. 2014. Community dynamics: lessons from a skeleton. In: "Frontiers in Ecology, Evolution and Complexity", Mariana Benítez, Octavio Miramontes & Alfonso Valiente-Banuet (Eds.). CopIt ArXives, Mexico. TS0012EN. ISBN:978-1-938128-05-9 (download the pdf in this link).

Keywords:

Community dynamics, Replacement dynamics, Coexistence, Disturbance, Recruitment, Successional dynamics.

Summary

A replacement model of woody plant communities (e.g. shrublands and forests) considers that the change in species abundance in the community is driven by the replacement of dead individuals (or parts of them) of a given species by individuals of the same or a different species growing beneath (see for example Horn 1975). This conceptualization of plant community dynamics as replacement systems can be traced back at least to Grubb (1977), and has been recently advocated by Myster (2012). We are developing a model that describes this process and how it is affected by external disturbances, like fire or grazing.

Grubb, P. J. 1977. The maintenance of species richness in plant communities: the importance of the regeneration niche. Biological Reviews 52: 107-145

Horn, H. S. 1975. Markovian properties of forest succession. Pages 196-211 in M. L. Cody and J. M. Diamond, eds. Ecology and evolution of communities. Harvard University Press, Cambridge, MA.

Myster, R. W. 2012. Plants replacing plants: the future of community modeling and research. Botanical Review 78: 2-9

Funded by:

Plan de Apoyo a la Investigación, al Desarrollo Tecnológico y a la Innovación of the University of Jaén, Spain (sponsored by Caja Rural de Jaén).

Publications

58. Alcántara, J. M., Pulgar, M., Trøjelsgaard, K., Garrido, J. L. and P. J. Rey, Stochastic and deterministic effects on interactions between canopy and recruiting species in forest communities. Functional Ecology 32: 2264-2274

57. Rey, P. J., Cancio, I., Manzaneda, A. J., González-Robles, A., Valera, F., Salido, T. and J. M. Alcántara. 2018. Regeneration of a keystone semiarid shrub over its range in Spain: habitat degradation overrides the positive effects of plant-animal mutualisms. Plant Biology: in press.

56 Garrido, J. L., J. M. Alcántara, P. J. Rey, M. Medrano, J. Guitián, M. C. Catellanos, J. M. Bastida, R. Jaime and C. M. Herrera. 2018. Geographic genetic structure of Iberian columbines (gen. Aquilegia). Plant Systematics and Evolution 303: 1145-1160

55 Rey, P. J., I. Cancio, A. González-Robles, J. M. Bastida, A. J. Manzaneda, F. J. Valera, T. Salido and J. M. Alcántara. 2017. Local scale and landscape disturbances impact through distinct pathways on the regional variation in seed dispersal by mammals in threatened semiarid habitats. Perspectives in Plant Ecology, Evolution and Systematics 28: 10-18

54 Rey, P. J., A. J. Manzanada and J. M. Alcántara. 2017. The interplay between aridity and competition determines colonization ability, exclusion and ecological segregation in the heteroploid Brachypodium distachyon species complex. New Phytologist 215: 85-96

53 Pulgar, M., J. M. Alcántara and P. J. Rey. 2017. Effects of sampling effort on estimates of the structure of replacement networks. Journal of Vegetation Science 28: 445-457

52 Alcántara, J. M., M. Pulgar and P. J. Rey. 2017. Dissecting the role of transitivity and intransitivity on coexistence in competing species networks. Theoretical Ecology 10: 207-215. (Read the full paper)

51 González-Robles, A., A. J. Manzaneda, J. M. Bastida, N. Harvey, R. Jaime, T. Salido, L. M. Martínez, A. Fernández-Ocaña, J. M. Alcántara and P. J. Rey. 2016. Development and characterization of microsatellite primers in the endangered Mediterranean shrub Ziziphus lotus (Rhamnaceae). Applications in Plant Sciences 4(12): 1600092 (DOWNLOAD)

50 Rey, P. J., Alcántara, J. M., Manzaneda, A. J. and Sánchez-Lafuente. A. M. 2016. Facilitation contributes to Mediterranean woody plant diversity but does not shape the diversity-productivity relationship along aridity gradients. New Phytologist 211:464-476.

49 Nogueira, A., Rey, P. J., Alcántara, J. M. and Lohmann, L. 2015. Evidence of between-population differences in natural selection on extrafloral nectaries of the shrub Anemopaegma album (Bignoniaceae). Botany 94:201-213.

48 Nogueira, A., P. J. Rey, J. M. Alcántara, R. M. Feitosa and L. G. Lohmann. 2015. Geographic mosaic of plant Evolution: extrafloral nectary variation mediated by ant and herbivore assemblages. PLoS ONE 10: e0123806. doi:10.1371/journal.pone.0123806 (DOWNLOAD)

47 Jaime, R., J. M. Alcántara, J. M. Bastida and P. J. Rey. 2015. Complex patterns of environmental niche evolution in Iberian Columbines (genus Aquilegia, Ranunculaceae). Journal of Plant Ecology 8: 457-467.

46 Alcántara, J. M., Rey, P. J. and Manzaneda, A. J. 2015. A model of plant community dynamics based on plant replacement networks. Journal of Vegetation Science. 26:524-537.

45 Valiente-Banuet A., Aizen, M. A., Alcántara, J. M., Arroyo, J., Cocucci, A., Galetti, M., García, M. B., García, D., Gómez, J.M., Jordano, P., Medel, R., Navarro, L. Obeso, J. R., Oviedo, R., Ramírez, N., Rey, P. J., Traveset, A., Verdú, M. and Zamora, R. 2015. Beyond species loss: the extinction of ecological interactions in a changing world. Functional Ecology. 29: 299-307.

44 Bastida, J. M., Rey, P. J. and Alcántara, J. M. 2014. Local adaptation to distinct elevational cores contributes to current elevational divergence of two Aquilegia vulgaris subspecies. Journal of Plant Ecology.

43 Alcántara, J. M. and Rey, P. J. 2014. Community dynamics: lessons from a skeleton. In: "Frontiers in Ecology, Evolution and Complexity", Benítez, m., Miramontes, O. and Valiente-Banuet, A. (Eds.). CopIt ArXives, Mexico. TS0012EN. ISBN:978-1-938128-05-9 (DOWNLOAD).

42 Rey, P. J. and Alcántara, J. M. 2014. Effects of habitat alteration on the effectiveness of plant-avian seed dispersal mutualisms: consequences for plant regeneration. Perspectives in Plant Ecology, Evolution and Systematics 16: 21-31

41 Alcántara, J. M., Jaime, R., Bastida, J. M. and Rey, P. J. 2014. The role of genetic constraints on the diversification of Iberian taxa of the genus Aquilegia (Ranunculaceae). Biological Journal of the Linnean Society 111: 252-261

40 Jaime, R., Serichol, C., Alcántara, J. M. and Rey, P. J. 2013. Differences in gas exchange contribute to habitat differentiation in Iberian columbines from contrasting light and water environment. Plant Biology 16: 354-364

39 Bastida, J. M., Rey, P. J. and Alcántara, J. M. 2014. Plant performance and morpho-functional differentiation in response to edaphic variation in Iberian columbines: cues for range distribution? Journal of Plant Ecology 7: 403-412 (DOWNLOAD).

38 Jaime, R., Rey, P. J., Alcántara, J. M. and Bastida, J. M. 2013. Glandular trichomes as an inflorescence defence mechanism against insect herbivores in Iberian columbines. Oecologia 172: 1051-1060

37 Alcántara, J. M. and Prey, P. J. 2012. Linking topological structure and dynamics in ecological networks. American Naturalist 180: 186-199

36 Castellanos, M. C., Alcántara, J. M., Rey, P.J. and J. M. Bastida. 2011. Intra-population comparison of vegetative and floral trait heritabilities estimated from molecular markers in wild Aquilegia populations. Molecular Ecology 20: 3513-3524

35 Rey, P.J. and Alcántara, J. M. 2011. Reforestación. Nuevos modelos basados en la dinámica de la vegetación. Investigación y Ciencia 413

34 Bastida, J. M., Bueno, R.J, Alcántara, J. M. and Rey, P.J. 2011. Habitat transitions and patterns of diversification of the genus Aquilegia in the Mediterranean context. Fitosociologia 48: In press

33 Alcántara, J. M., Rey, P. J., Jiménez-Melero, Ramírez, J. M., R., Bastida, J.M., Cancio, I. and G. Siles. 2011. Desarrollo de herramientas de diagnosis del estado de recuperación de la vegetación tras incendios en la Sierra Sur de Jaén. In: Proyectos de Investigación 2008-2009. Pages 27-40. Universidad de Jaén

32 Siles, G., Alcántara, J. M., Rey, P.J. and J. M. Bastida. 2010. Post-fire Restoration of Mediterranean forests: testing assembly rules mediated by facilitation. Basic and Applied Ecology 11: 422-431

31 Siles, G., Alcántara, J. M., Rey, P.J. and J. M. Bastida. 2010. Defining a Target Map of Native Species Assemblages for Restoration. Restoration Ecology 18: 439-448

30 Alcántara, J. M., Bastida, J. M. and Rey, P.J. 2010. Linking divergent selection on vegetative traits to environmental variation and phenotypic diversification in the Iberian Columbines (Aquilegia). Journal of Evolutionary Biology 23: 1218-1223

29 Siles, G., Rey, P.J., Alcántara, J. M., Bastida, J. M. and J. L. Herreros. 2010. Effects of soil enrichment, watering and seedling age on establishment of Mediterranean woody species. Acta Oecologica 36: 357-364

28 Bastida, J. M., Alcántara, J. M., Rey, P.J., Vargas, P. and Herrera, C. M. 2010. Extended phylogeny of Aquilegia: the biogeographical and ecological patterns of two simultaneous but contrasting radiations. Plant Systematics and Evolution 284:171-185

27 Rey, P. J., Alcántara, J. M. and Fernández, J. M. 2009. Bosques de Olea y Ceratonia. In: Bases ecológicas preliminares para la conservación de los tipos de hábitat de interés comunitario en España. Ministerio de Medio Ambiente, y Rural y Marino

26 Rey, P. J., Alcántara, J. M., Manzaneda, A. J., Garrido, J. L. and Ramírez, J. M. 2009. Variación geográfica y mosaicos de selección en las interacciones planta-animal. In: R. Medel, M. A. Aizen and R. Zamora (Eds.). Ecología y evolución de las interacciones planta-animal. Pages 113-132. Editorial Universitaria-Santiago de Chile.

25 Manzaneda, A. J., Rey, P.J. and Alcántara, J. M. 2009. Conflicting selection on diaspore traits limits the evolutionary potential of seed dispersal by ants. Journal of Evolutionary Biology 22: 1407-1417

24 Rey, P.J., Siles, G. and Alcántara, J. M. 2009. Community-level restoration profiles in Mediterranean vegetation: nurse-based vs. traditional reforestation. Journal of Applied Ecology 46: 937-945

23 Verdú, M., Rey, P.J., Alcántara, J. M., Siles, G. and Valiente-Banuet, A. 2009. Phylogenetic signatures of facilitation and competition in successional communities. Journal of Ecology 97: 1171-1180

22 Siles, G., Rey, P.J., Alcántara, J. M., and J. M. Ramírez. 2008. Assessing the long-term contribution of nurse plants to restoration of Mediterranean forests through Markovian models. Journal of Applied Ecology 45: 1790-1798

21 Alcántara, J. M., P. J. Rey, J. A. Manzaneda, R. Boulay, J. M. Ramírez and J. M. Fedriani. 2007. Geographic variation in the adaptive landscape for seed size at dispersal in the myrmecochorous Helleborus foetidus. Evolutionary Ecology 21: 411-430

20 Ramírez, J. M., Rey, P. J., Sánchez-Lafuente, A. M. and Alcántara, J. M. 2006. Altitudinal and microclimatic effects on the establishment of a perennial herb in a Mediterranean mountain. Ecography 29: 375-384

19 Siles, G., Herreros, J. L., Alcántara, J. M. and Rey, P. J. 2005. Modelos predictivos de distribución de especies de vegetación potencial en el incendio del "Puerto de las Palomas", Sierra de Cazorla, Jaén. Cuadernos de la Sociedad Española de Ciencias Forestales 20: 167-172.

18 Rey, P. J., Alcántara, J. M., Valera, F., Sánchez-Lafuente, A. M., Garrido, J. L., Ramírez, J. M. and Manzaneda, A. J. 2004. Seedling establishment in Olea europaea. Seed size and microhabitat affect growth and survival. Ecoscience 11: 310-320

17 Siles, G., Herreros, J. L., Rey, P. J., y Alcántara, J. M. 2004. Una investigación en desarrollo: nuevas técnicas de reforestación en el incendio del Puerto de Las Palomas. Anuario del Adelantamiento. Cazorla 46: 80-85

16 Alcántara, J. M. and Rey, P. J. 2003. Conflicting selection pressures on seed size: evolutionary ecology of fruit size in a bird-dispersed tree, Olea europaea. Journal of Evolutionary Biology 16: 1168-1176

15 Rey, P. J., Garrido, J. L., Alcántara, J. M., Ramírez, J. M., Aguilera, A., García, L., Manzaneda, A. J. and Fernández, R. 2002. Spatial variation in ant and rodent post-dispersal predation of vertebrate-dispersed seeds. Functional Ecology 16: 773-783

14 Rey, P. J. and Alcántara, J. M. 2000. Recruitment dynamics of a fleshy-fruited plant (Olea europaea): connecting patterns of seed dispersal to seedling establishment. Journal of Ecology 88: 622-633

13 Alcántara, J. M., Rey, P. J., Valera, F. and Sánchez-Lafuente, A. M. 2000. Factors shaping the seedfall pattern of a bird-dispersed plant. Ecology 81: 1937-1950

12 Alcántara, J. M., Rey, P. J., Sánchez-Lafuente, A. M. and Valera, F. 2000. Early effects of rodent post-dispersal seed predation on the outcome of the plant-seed disperser interaction. Oikos 88: 362-370

11 Sánchez-Lafuente, A. M., Rey, P. J., Alcántara, J. M. and Valera, F. 1999. Breeding system and the role of floral visitors in seed production of a "few-flowered" perennial herb, Paeonia broteroi Boiss. & Reut. (Paeoniaceae). Ecoscience 6: 163-172

10 Valera, F., Rey, P. J., Sánchez-Lafuente, A. M. and Alcántara, J. M. 1999. El uso de herbicidas y la conservación del medioambiente: efectos sobre la flora y fauna. In: Control integrado de malas hierbas: buenas prácticas agrícolas. Pages 23-36. Phytoma-España

9 Sánchez-Lafuente, A. M., Alcántara, J. M. and Romero, M. 1998. Nest-site selection and nest predation in the Purple Swamphen. Journal of Field Ornithology 69: 563-576

8 Alcántara, J. M., Rey, P. J., Valera, F., Sánchez-Lafuente, A. M. and Gutiérrez, J. E. 1997. Habitat alteration and plant intra-specific competition for seed dispersers. An example with Olea europaea var. sylvestris. Oikos 79: 291-300

7 Rey, P. J., Gutiérrez, J. E., Alcántara, J. M. and Valera, F. 1997. Fruit size in wild olives: implications for avian seed dispersal. Functional Ecology 11: 611-618

6 Alcántara, J. M., Vera, N. E., Szczpanski, L., Eibl, B. I. and Ríos, R. 1997. Análisis de la dispersión de semillas de Cedrela fissilis en el bosque nativo de Misiones. Yvyraretá 8:16-21

5 Alcántara, J. M., Rey, P. J., Valera, F., Gutiérrez, J. E. and Sánchez-Lafuente, A. M. 1997. Temporal pattern of seed dispersal of wild olive (Olea europaea var. sylvestris): its effect on intra-specific competition. Lagascalia 19: 583-590

4 Alcántara, J. M., Rey, P. J., Valera, F. and Sánchez-Lafuente, A. M. 1997. Pérdidas de fruto y movilización de semillas en Olea europaea var. sylvestris Brot. (Oleaceae). Anales del Jardín Botánico de Madrid 55: 101-110

3 Valera, F., Rey, P. J., Sánchez-Lafuente, A. M. and Alcántara, J. M. 1997. Efecto de los sistemas de laboreo sobre las aves. In: Agricultura de conservación: fundamentos agronómicos, medioambientales y económicos. Pages 225-243. Asociación Española Laboreo de Conservación/Suelos Vivos

2 Rey, P. J., Alcántara, J. M. and Sánchez-Lafuente, A. M. 1996. Temporal variation in food availability and diet of Blackcaps in olive orchards. Journal of Field Ornithology 67: 592-603.

1 Espinosa, M. A., Alcántara, J. M. and Fernández, C. 1994. Fenología de algunos geófitos de Jaén. Blancoana 11: 14-20