Forest fragmentation and edge effects on the genetic structure ofClusia sphaerocarpaandC. lechleri(Clusiaceae) in tropical montane forests

Abstract

2013). Forest fragmentation and edge effects on the genetic structure of Clusia sphaerocarpa and C. lechleri (Clusiaceae) in tropical montane forests.Abstract: Fragmentation of tropical forests influences abiotic and biotic processes that affect the genetic structure of plant populations. In forest fragments, edge effects, i.e. changes of abiotic and biotic factors at forest edges, may be prevalent. In two forest fragments (c. 200 ha at c. 2450 m asl) of tropical montane forest in Bolivia, sympatric populations of the dioecious tree species Clusia sphaerocarpa and C. lechleri were used as case study species to compare genetic diversity and small-scale genetic structure (SGS) between edge and interior habitats. Eight microsatellite markers were employed to genotype 343 individuals including adults, juveniles and seedlings of C. sphaerocarpa and 196 of C. lechleri. Genetic differentiation was found between habitats in both species ( RT = 0.071 for C. sphaerocarpa and RT = 0.028 for C. lechleri) and among ages in C. sphaerocarpa ( RT = 0.016). Overall, SGS was weak but significant with more pronounced SGS in C. lechleri (Sp = 0.0128) than in C. sphaerocarpa (Sp = 0.0073). However, positive spatial genetic autocorrelation extended only up to 10 m. For C. sphaerocarpa, SGS was stronger in seedling and juvenile stages than in adults and in the forest interior than at forest edges. Our results show that edge effects can extend to the genetic level by breaking-up local genetic structures, probably due to increased gene flow and enhanced pollination and seed-dispersal interactions at forest edges.

Genetic structure and post‐glacial expansion ofCornus floridaL. (Cornaceae): integrative evidence from phylogeography, population demographic history, and species distribution modeling

“…Special attention should be given to monitoring and conserving these northern populations due to their rarity and importance in serving as sources for future dispersal to the north in response to global warming (Feurdean et al, 2013). In general, populations on edge of a species range are likely to be genetically different from those in the center of the range (Cook, 1961;Quevedo et al, 2013). Thus, preserving those populations may preserve genetic attributes that are unique to these populations, and help to maintain the overall genetic diversity of a region or ecosystem (Hampe & Petit, 2005).…”

Impacts of Habitat Degradation on Tropical Montane Biodiversity and Ecosystem Services: A Systematic Map for Identifying Future Research Priorities

“…Other genetic studies were published from 2011 to 2015, with six from Latin America, four from Africa and one from Asia ( Table 2). Most explored the impacts of habitat degradation on a single focal species, but two drew comparisons between two species (Winkler et al, 2011;Quevedo et al, 2013), and another compared seven species (Callens et al, 2011). Most articles examined the impact of fragmentation or edge effects on genetic diversity or gene flow, while a few studied the effects of deforestation or land-use change ( Table 2).…”

Low Divergence Among Natural Populations of Cornus kousa subsp. chinensis Revealed by ISSR Markers

“…Considering the low genetic differentiation and high genetic diversity in populations of Chinese dogwood, in situ conservation is suitable for its cost-effective preservation of genetic diversity. Furthermore, the populations from the fringes of the distribution (including HHF, JJ, SE, NB, JL, AT, and AW) should be specially monitored in the future because these populations are likely to be genetically different from those in the center of the distribution area [38] and could contribute to genetic diversity and further development and utilization of the species.…”