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Abstract• Genetic structures of five population pairs each consisting of one natural population and one neighbouring plantation of Pinus roxburghii Sarg. in Nepal were assessed using nuclear (nSSRs) and chloroplast microsatellite loci (cpSSRs).• The mean number of alleles at nSSRs loci in natural populations was 5.0 compared to 4.93 in plantations while the average observed heterozygosities were the same in both groups (H 0 = 0.50). Most of the alleles were common to all the populations, indicating that the populations correspond to a single genetic entity. Similarly forty-seven haplotypes were observed in natural populations compared to fifty haplotypes in plantations. Mean haplotype diversities of natural populations (0.953) and plantations (0.955) were very similar. Genetic diversity of Pinus roxburghii was relatively high with low or no evidence of inbreeding while genetic differentiation among all populations was very low (about 1%).• The very low differentiation among natural populations indicates efficient long-distance gene flow among populations resulting in homogeneous genetic structures at least at selectively neutral loci. Even though the harvest and production of seeds and seedlings was largely uncontrolled, genetic structures of most plantations show no signs of reduced variation, inbreeding or other negative effects compromising the adaptedness or adaptability of planted forests. • Les structures génétique de cinq paires de populations composées chacune d'une population naturelle et d'une plantation voisine de Pinus roxburghii Sarg. au Népal ont été évalués à l'aide de loci nucléaires (nSSRs) et de loci microsatellites chloroplastiques (cpSSRs). Mots• Le nombre moyen d'allèles à loci nSSRs dans les populations naturelles était de 5,0 comparé à 4,93 dans les plantations alors que la moyenne des hétérozygoties observées étaient les mêmes dans les deux groupes (H 0 = 0,50). La plupart des allèles étaient communs à toutes les populations, indiquant que les populations correspondent à une seule entité génétique. De même, quarante-sept haplotypes ont été observés dans les populations naturelles par rapport à cinquante haplotypes dans les plantations. La diversité moyenne des haplotypes des populations naturelles (0,953) et des plantations (0,955) étaient très similaires. La diversité génétique de Pinus roxburghii a été relativement importante, avec peu ou pas de preuve de consanguinité tandis que la différenciation génétique entre les populations était très faible (environ 1 %).• Le très faible différenciation entre les populations naturelles indique des flux de gènes efficaces à longue distance entre les populations issues de structures génétiques homogènes avec au moins une sélectivité neutre des loci. Même si la récolte et la production de semences et de plants ont été largement incontrôlées, les structures génétiques de la plupart des plantations ne montrent aucun signe de réduction de la variation de la consanguinité ou d'autres effets négatifs compromettant la faculté d'adaptation des forêts plant...

Genetic diversity and population structure of Tasmanian populations of Eucalyptus pauciflora were assessed using chloroplast and nuclear microsatellite markers. Maternal trees and open-pollinated progeny from 37 populations were sampled across the species’ geographic and altitudinal distribution in Tasmania. The distribution of chloroplast haplotype richness showed a clear geographic structure with suggestion of three major refugia (Storm Bay, Tamar Valley and St Pauls River Valley), two of which are consistent with previously reported glacial refugia. Chloroplast haplotype affinities provided evidence of migration of populations from the north and east towards the south and west of Tasmania. High nuclear microsatellite diversity was observed across the species’ range. Most of this variation was distributed within populations with low but significant FST, suggesting high gene flow among populations that is more pronounced in mature stands. Higher nuclear genetic diversity in newly colonised areas compared with lowland putative refugial regions, and the converse in chloroplast DNA markers, suggest limited seed dispersal into newly colonised regions combined with high pollen flow between different source populations in newly colonised areas. Our results do not support the suggestion that highland populations of E. pauciflora originate from in situ high-altitude refugia, but instead argue they originate from lowland refugia.

Habitat fragmentation is a key factor causing variation in important mating system parameters in plants, but its effect is variable. We studied mating system variation among 276 native trees from 37 populations of Eucalyptus pauciflora from Tasmania. We assayed 10 microsatellite loci from 1359 open-pollinated progeny from these trees. Across Tasmania the species’ mating system was characterised by a high outcrossing rate (tm = 0.90) but moderate bi-parental inbreeding (tm–ts = 0.16) and moderate correlated paternity (rP = 0.20) in comparison to other eucalypt species. Despite significant differences in outcrossing rate and correlated paternity among populations, this variation was not correlated with fragmentation. Nevertheless, fragmentation was inversely correlated with the number of germinants per gram of seed capsule content. Outcrossing rate had been reported previously to decrease with increasing altitude in mainland populations of E. pauciflora, but this was not the case in Tasmania. However, a small but significant decrease in correlated paternity occurred with increasing altitude and a decrease in bi-parental inbreeding with increasing altitude was evident in fragmented populations only. It is argued that strong, but incomplete self-incompatibility mechanisms may buffer the mating system from changes in population density and pollinators. While seed yields from highly fragmented populations were reduced, in most cases the seed obtained is unlikely to be more inbred than that from non-fragmented populations and, thus, is likely to be as suitable for use in local forest restoration.

In an effort to reverse the trend of deforestation and forest degradation, several international initiatives have been attempted. Though promoted in different political arenas, Forest Law Enforcement, Governance and Trade (FLEGT) – Voluntary Partnership Agreement (VPA), and Reducing Emissions from Deforestation and forest Degradation in developing countries (REDD+) share overlapping objectives of conservation of tropical forests. We explore specialists' viewpoint on FLEGT-VPA and REDD+ processes in Indonesia with reference to their contribution towards Sustainable Forest Management (SFM). The study shows that FLEGT-VPA and REDD+ regimes contribute towards SFM. While FLEGT-VPA improves enabling condition for SFM through governance reform, improved harvesting practices, and timber legality assurance system, REDD+ supports SFM through institutional strengthening, reforming policies and frameworks, mobilizing new and additional financial resources and increasing social and ecological resilience. We identified opportunities to achieve synergies between REDD+ and FLEGT-VPA by harmonizing their processes, tools, methodologies, technical assistance, capacity-building and funding mechanisms.