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Tree species selection for ecological restoration : An example from Mexican tropical riversides. Paula Meli Miguel Martínez Ramos José María Rey Benayas. IV World Congress of Ecological Restoration Mérida, Yucatán, México. Introduction.
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Treespeciesselectionforecologicalrestoration: AnexamplefromMexican tropical riversides Paula Meli Miguel Martínez Ramos José María Rey Benayas IV World Congress of Ecological Restoration Mérida, Yucatán, México
Introduction • Speciesselectionisone of themostimportantsteps in ecologicalrestoration • In manyregions, informationaboutspeciesexistsonlyfor a limitednumber of commerciallyvaluablespecies. • For most native forest types, it is unlikely that sufficient published information exists to select candidate framework species for further investigation (Blackeley et al. 2002). • Local knowledge and social perception are important (Blackeley et al. 2002; Garibaldi & Turner 2005).
Introduction • Some criteria to select species with restoration purposes: • There is litlle effort to integrate different kind of informatiom. • Multivariate methods can be used but dataset are frequently incomplete.
Objective Develop a «species selection index» useful for restoration purposes in riversides of humid tropics of Mexico that… • Considers ecological, social and technical criteria. • Could be «adaptive» (improved permanently). • Could be «versatile» (applicable to different ecosystems and regions).
Study site Marqués de Comillas, Chiapas RBMA Rio Lacantún • 330,000 hectares of tropical rainforest • Five geomorphological types • High biodiversity • Endemisms of several taxa Marqués de Comillas
Deforestation includes riversides • Loss of fish and invertebrate biodiversity in streams • People state that water provision diminished and riversides are eroded EcologicalRestoration of riversides in humid tropical Mexico Selecttreespeciesfor active restoration of Marqués de Comillas riversides
Methods We propose six criteria:
Criteria 1: Natural importance in referenceecosystems (NI) • Floristic inventory in conserved riversides (50x10m) • Only trees and shrubs >1.5cm diameter • Importance value index (IVI) (Mueller-Dombois & Ellenberg 1974) Example of the first 15 species… IVI relativized to the maximun value NI = continuous variable (0-1)
Criteria 2: Natural regenerationpontential (NRP) • Floristic inventory in secondary riversides 6-15 yrs old (50x10m) • Only trees and shrubs >1.5cm diameter • Spearman coefficient : Log (diametrical class) vs. Log (frequency+1) Example: r = -0.917; p <0.001 Ficus cotinifolia: r = -0.1; p = 0.770 Croton shiedeanus: Lower r indicateshigh NRP Lessinterestforactive restoration NRP = continuous variable [-1 , 1]
Criteria 3: Adaptabilitytodifferentenvironments (Ad) Alluvial Karstic Lowlands Flooding (inundable) Savanna • Regional distribution • 5 ecosystems types • 3-5 plots in each ecosystem type • Species frequency Ad = # ecosystems Ad = discrete variable (0-5)
Criteria 4: Ecosystemservices and functions (ES) Ecosystem servicies and functions: • Polinization / Dispersors attractor • Food provision or raw materials • Carbon storage • Cultural value • etc… Balvanera et al. (2005) ES = continuous variable Example of the some species…
Criteria 5: Social value and perceptions (SV) • 4 workshops with local population (>40 local farmers) • Working in groups • Working with species cards • Collection of species information: name, natural abundance in riversides, local uses, life history, propagation.
Social value (SV) = Abundance in riversides (ranks) * Number of local uses Examples: SV (Inga vera) = 5 * 1 = 5 SV (Vochysia guatemalensis) = 3 * 2 = 6 # uses 1 SV = discrete variable 1 1 0 2 1 0 2 2 1 1 1 1 1 0 4
Criteria 6: Technicallimitations (T) • Modified from Knowles & Parrotta (1995) T = discrete variable (3-9)
Results SpeciesSelectionIndex (fragment) SSI = NI + NRP + Ad/5 + ES + SV/max. value + T/9
Results SpeciesSelectionIndex (fragment) SSI = NI + NRP + Ad/5 + ES + SV/max. value + T/9
Discussion • This index integrates ecological, social and technical information. • Notalwaysavailablealltheinformationforallspecies, butitshould be thegoal at mediumterm. • Applicabletodifferentregions and ecosystems. • Easytoadaptwhendifferentneeds (e.g. weightening social ortechicalcriteria). • Natural regenerationpotentialshould be used as negativecriteria, becausewe are selectingspeciesforactive restoration. • Ecosystemservices and functionsisone of themostdifficultcriteriatointerpretate and itmustto be revised. • Conventional techniques developed for native species would be inappropriate for isolated small-scale nurseries. Innovative strategies are needed (Knowles & Parrotta 1995).
Funding from the following organizations is gratefully acknowledged. Thanks!! Gracias!!