Canadian Journal of Forest Research Spatial genetic structure, population dynamics and spatial patterns in the distribution of Ocotea catharinensis Mez. from southern Brazil: implications for conservation Journal: Canadian Journal of Forest Research Manuscript ID cjfr-2017-0446.R1 Manuscript Type: Article Date Submitted by the Author: 05-Feb-2018 Complete List of Authors: Montagna, Tiago; Universidade Federal de Santa Catarina, Fitotecnia Lauterjung, Miguel; Universidade Federal de Santa Catarina, Fitotecnia Candido-Ribeiro,Draft Rafael; Universidade Federal de Santa Catarina, Fitotecnia Silva, Juliano; Universidade Federal de Santa Catarina, Fitotecnia Hoeltgebaum, Marcia; Universidade Federal de Santa Catarina, Fitotecnia Costa, Newton; Universidade Federal de Santa Catarina, Fitotecnia Bernardi, Alison; Universidade Federal de Santa Catarina, Fitotecnia Reis, Maurício; Universidade Federal de Santa Catarina, Fitotecnia Atlantic Rainforest, fine-scale spatial genetic structure, genetic diversity, Keyword: neighborhood size, seed collection Is the invited manuscript for consideration in a Special N/A Issue? : https://mc06.manuscriptcentral.com/cjfr-pubs Page 1 of 44 Canadian Journal of Forest Research 1 1 Spatial genetic structure, population dynamics and spatial patterns in the distribution of 2 Ocotea catharinensis Mez. from southern Brazil: implications for conservation 3 4 Tiago Montagna1, Miguel Busarello Lauterjung2, Rafael Candido-Ribeiro3ϯ, Juliano Zago 5 da Silva4, Marcia Patricia Hoeltgebaum5, Newton Clóvis Freitas da Costa6, Alison Paulo 6 Bernardi7, Maurício Sedrez dos Reis8. 7 8 Affiliation and address of all authors: Núcleo de Pesquisas em Florestas Tropicais, Pós- 9 Graduação em Recursos Genéticos Vegetais, Centro de Ciências Agrárias, Universidade 10 Federal de Santa Catarina. Rodovia Admar Gonzaga, 1346. Florianópolis, Santa Catarina, 11 Brazil. Draft 12 13 Email adresses of all authors: [email protected], [email protected], 14 [email protected], [email protected], [email protected], 15 [email protected], [email protected], [email protected] 16 17 Corresponding author: Tiago Montagna. Address: Rodovia Admar Gonzaga, 1346. 18 Florianópolis, Santa Catarina, Brazil. Telephone/Fax: +55 48 3721 5322. Email: 19 [email protected]. ORCID: 0000-0002-7427-4237 ϯCurrent affiliation: Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, Canada. https://mc06.manuscriptcentral.com/cjfr-pubs Canadian Journal of Forest Research Page 2 of 44 2 20 Abstract 21 In this study, we employ an integrated demographic/genetic approach with the aim of 22 informing efforts to conserve Ocotea catharinensis, an endangered tree species from the 23 Brazilian Atlantic Rainforest. After establishing two permanent plots (15 and 15.5 ha) 24 within Protected Areas in Santa Catarina state, Brazil, we evaluated demographic aspects 25 (density, recruitment, mortality and growth), spatial pattern, genetic diversity and spatial 26 genetic structure (SGS) in three categories of individuals (seedlings, juveniles and 27 reproductive) over two years. Studied populations presented low recruitment of individuals 28 and low rates of increment in diameter and height. Aggregation was the main spatial pattern 29 observed for both populations. High levels of genetic diversity were estimated for both 30 populations, but also high levels ofDraft fixation index, signaling the risK of losing genetic 31 diversity over generations. Significant SGS was found for both populations, reflecting 32 nonrandom distribution of the genotypes. Demographic and genetic surveys also allowed 33 the estimation of minimum viable areas for genetic conservation (> 170 ha), deme sizes 34 (around 10 ha) and distances for seed collection (at least 60 m). Effective population size is 35 restricted in studied populations, locally threatening the species perpetuation over 36 generations. Further research can clarify how this condition it will change in subsequent 37 years. 38 39 Keywords: Atlantic Rainforest, fine-scale spatial genetic structure, genetic diversity, 40 neighborhood size, seed collection https://mc06.manuscriptcentral.com/cjfr-pubs Page 3 of 44 Canadian Journal of Forest Research 3 41 Introduction 42 Demographic and genetic studies are basic and powerful tools to understand 43 dynamic processes at the population level and their maintenance over time (Griffith et al. 44 2016, Lowe et al. 2017). Population structure can be described in terms of the ages, sizes, 45 and forms of the individuals that composes it, and population structure is susceptible to 46 environmental conditions and dynamic processes, such as recruitment, mortality and 47 growth rates, as well as intra- and interspecific competition (Harper and White 1974). 48 Therefore, demographic studies can help us predict decline, stability or expansion in 49 populations (Paludo et al. 2016), predict impacts of management practices on the structure 50 of populations (Ribeiro et al. 2014), and unravel environmental and ecological aspects that 51 determine demographic parameters andDraft spatial patterns of distribution (Lara-Romero et al. 52 2016). 53 Genetic structure, in turn, results from the spatial nonrandom distribution of 54 genotypes in space (VeKemans and Hardy 2004). At a more restricted scale (e.g., within a 55 population), genetic structure largely arises from the formation of local pedigrees caused by 56 limited gene flow (VeKemans and Hardy 2004). Life history traits, such as regeneration 57 mode (e.g., sprouting or non-sprouting species), plus coarse- and fine-scale disturbances 58 (e.g., gaps, fires, landslides) and particular conditions for seedling establishment can also 59 lead to genetic structuring (Mathiasen and Premoli 2013). Genetic structure within a 60 population is commonly Known as spatial genetic structure (SGS), or fine-scale spatial 61 genetic structure. Studies of SGS and its causes have provided fundamental guidelines for 62 plant conservation and actions, e.g., minimum distances required for seed collections 63 (Tarazi et al. 2010), associations between habitat fragmentation and SGS (Santos et al. 64 2016), and estimates of neighborhood sizes (Buzatti et al. 2012). By using information https://mc06.manuscriptcentral.com/cjfr-pubs Canadian Journal of Forest Research Page 4 of 44 4 65 gained from both demographic and genetic studies, we might be able to propose feasible 66 management and conservation strategies for plant species. 67 Ocotea catharinensis Mez. is a tree species that occurs in the Brazilian Atlantic 68 Rainforest (AR) between latitudes 19°57' S (Saiter and Thomaz 2014) and 30°15' S 69 (Carvalho 1994). This species was considered the most abundant and dominant tree in the 70 upper stratum of Ombrophilous Dense Forest, a forest formation of the AR (Veloso and 71 Klein 1959, Klein 1980) in southern Brazil. However, the intensive exploitation of O. 72 catharinensis to produce timber, combined with the high fragmentation of AR (Ribeiro et 73 al. 2009, Vibrans et al. 2012), led to the placement of this species on the Brazilian List of 74 Endangered Plant Species (MMA 2014). The species is also classified as vulnerable by the 75 IUCN Red List (Varty and GuadagninDraft 1998). 76 Currently, the species occurs at an average density of 5.86 individuals/ha (diameter 77 at breast height – dbh > 10 cm) in remnants of Ombrophilous Dense Forest in Santa 78 Catarina state (SC) (Lingner et al. 2013). However, in the past, higher densities were 79 recorded, ranging from 23.9 individuals/ha (dbh > 12.7 cm) (Veloso and Klein 1959) up to 80 20 to 50 reproductive individuals/ha (Reitz et al. 1978). Densities of 200 up to 600 81 individuals/ha higher than 1 m were also reported for SC (Reitz et al. 1978). These major 82 differences between past and present densities call for studies to support conservation 83 efforts regarding O. catharinensis. 84 Indeed, studies reporting on the demographic aspects of O. catharinensis have 85 already been carried out (Veloso and Klein 1959, Tarazi et al. 2010, Lingner et al. 2013). 86 Nevertheless, such studies have neither covered seedling densities nor focused on 87 population dynamics (e.g., growth rates, mortality and recruitment). Ocotea catharinensis 88 presents an aggregated spatial pattern (Tarazi et al. 2010); however, not only is the extent https://mc06.manuscriptcentral.com/cjfr-pubs Page 5 of 44 Canadian Journal of Forest Research 5 89 of this aggregation unKnown, but also possible variations in the extent and the intensity of 90 the spatial pattern between different categories of individuals (e.g., seedlings, juveniles or 91 reproductive). High levels of genetic diversity, low to moderate levels of fixation index, 92 and moderate genetic divergence are reported for O. catharinensis populations (Tarazi et al. 93 2010, Martins et al. 2015). Furthermore, significant SGS within the populations of O. 94 catharinensis have already been detected (Tarazi et al. 2010). So far, however, genetic 95 diversity and SGS within different categories of individuals are poorly understood. 96 In this study, we described the population dynamics, spatial pattern and SGS of 97 three categories of O. catharinensis individuals (seedlings, juveniles, and reproductive) 98 from two populations in SC, southern Brazil. We asKed i) how the demographic structure 99 varies over the years, ii) how individualsDraft are spatially distributed, and iii) what is the 100 magnitude of SGS in those populations.