Ecological considerations for using dipterocarps for restoration of lowland rainforest in Southeast Asia

The lowland dipterocarp forests of Southeast Asia support a substantial proportion of the world's biodiversity. They are of considerable environmental and economic value at the local, regional and global scale, providing many goods and services to a growing population. The forests of this region are among the fastest disappearing in the world and restoration is urgently required. This paper provides a review of the ecological constraints to restoration of lowland dipterocarp forest in Southeast Asia. It focuses on the production of planting stock, the significance of site-species matching and post-planting site maintenance. It identifies gaps in our knowledge and highlights priority areas of research. Adopting a long-term view is essential for restoring as well as conserving the dipterocarp forests of Southeast Asia. An immediate strategy for the conservation and management of dwindling genetic resources of these important timber species is essential. This will provide the foundations for sourcing seed and production of planting material for longer term restoration. The importance of species-site matching, mycorrhizal fungi and post-planting maintenance for restoration are apparent. Financing is a major limiting factor to dipterocarp forest restoration. Trading in carbon, private finance and environmental markets afford considerable opportunities for restoring these forests providing their total value is recognised. Despite the wealth of ecological knowledge we already have for scientifically-informed forest restoration, without the backing of governments and corporate stakeholders, forest restoration will not gain the urgently required momentu

Fragmentation genetics in the tropics

On the 23rd of February, some 50 Conservation Geneticists from around the global gathered for a half day symposium entitled ‘Fragmentation Genetics in the Tropics' held at the Friedrich-Alexander University, Erlangen, Germany as part of the German Tropical Ecology Society annual meeting 2012. The overall aim of this symposium was to showcase the latest novel research applying molecular methods (landscape genetics, conservation genetics and phylogeography) to advance our understanding of genetic consequences of fragmentation in the tropics, particularly in the context of how population size and isolation influences population and species extinction. I provide a brief overview of the symposium and finish with a call for papers for a special issue of the sister journal Conservation Genetics, for which submission is now ope

Fragmentation genetics in tropical ecosystems: from fragmentation genetics to fragmentation genomics

Tropical regions are experiencing unprecedented economic and population growth. This goes hand in hand with increase habitat fragmentation of tropical ecosystems. Understanding the genetic consequences of these spatial and temporal changes across landscapes is critical to conservation of the vast majority of global biodiversity. This virtual issue of Conservation Genetics, presents six empirical and one review paper showcasing fascinating and important findings with regard to how habitat fragmentation impacts on genetic diversity in rare or endangered tropical species. The message from these papers is clear, fragmentation has a number of serious genetic consequences, which can contribute to undermining the viability of species in fragmented landscapes. Conservation genetics provides a powerful tool to inform both conservation and management of species and genetic resources. But, careful consideration is needed to ensure studies apply appropriate sampling designs and genetic analysis to better test hypothesis. Next generation genomics offers great opportunities to provide even more answers and greater resolution of the consequences for adaptive genetic variation, to ensure future tropical landscapes are resilient

Development of polymorphic microsatellite markers of the Seychelles endemic tree Glionnetia sericea (Rubiaceae)

Glionnetia sericea (Rubiaceae) is an endemic and rare tree species of the Seychelles, restricted to altitudes between 500 and 900m with less than 1,000 remaining individuals. It survives in mist forests but also in smaller populations on granitic outcrops (inselbergs) and is pollinated by hawk moths which might ensure long-distance pollen flow. Understanding the reproductive ecology of this species will allow a better understanding on how such species survive in naturally fragmented habitats and will provide scientifically informed management recommendations. Here we report on ten species specific polymorphic microsatellite loci developed for a study of historic and contemporary gene flow. Based upon a sample of 81 adults, the number of alleles per locus ranged from 3 to 12 (mean of 6.1 per locus) with an average polymorphic information content of 0.52 across loci. Expected heterozygosity ranged from 0.27 to 0.82 with two of ten primers showing some deviation from Hardy-Weinberg expectatio

Development of polymorphic microsatellite markers of the endangered and endemic Vateriopsis seychellarum (Dipterocarpaceae), a relict canopy tree of the Seychelles

The Dipterocarpaceae are a globally significant family of tropical timber trees. They are especially dominant in lowland rainforests of Southeast Asia, but have a pan tropical distribution. Vateriopsis seychellarum is the sole representative of this family on the Seychelles. Historically one of the dominant canopy trees on Mahé, extensive overexploitation of this species for its timber has led to its virtual extinction. The last individuals of this species are found in small fragmented populations at lower altitudes (up to 400m) on the island of Mahé where the total number of known reproductive adults is 112. We developed ten polymorphic microsatellite loci for this species to enable us to quantify the levels of diversity in remnant populations and to study genetic structure and contemporary gene flow. In addition we tested for cross amplification of these alleles in the closely related but geographically disjunct species Vateria indica. In Vateriopsis seychellarum the number of alleles per locus ranged from 6 to 20 (mean of 11.4 per locus) with an average polymorphic information content of 0.73 across loci. Expected heterozygosity ranged from 0.40 to 0.71 with 3 of the 10 loci showing deviation from Hardy-Weinberg expectations. 8 of the 10 primers showed cross amplification in Vateria indica. These markers will help to provide a better understanding of the significance of historic distributions, gene flow and recent anthropogenic habitat degradation for the survival of widespread species in recently fragmented landscape

Extensive contemporary pollen-mediated gene flow in two herb species, Ranunculus bulbosus and Trifolium montanum, along an altitudinal gradient in a meadow landscape

Background and Aims Genetic connectivity between plant populations allows for exchange and dispersal of adaptive genes, which can facilitate plant population persistence particularly in rapidly changing environments. Methods Patterns of historic gene flow, flowering phenology and contemporary pollen flow were investigated in two common herbs, Ranunculus bulbosus and Trifolium montanum, along an altitudinal gradient of 1200-1800 m a.s.l. over a distance of 1 km among five alpine meadows in Switzerland. Key Results Historic gene flow was extensive, as revealed by Fst values of 0·01 and 0·007 in R. bulbosus and T. montanum, respectively, by similar levels of allelic richness among meadows and by the grouping of all individuals into one genetic cluster. Our data suggest contemporary pollen flow is not limited across altitudes in either species but is more pronounced in T. montanum, as indicated by the differential decay of among-sibships correlated paternity with increasing spatial distance. Flowering phenology among meadows was not a barrier to pollen flow in T. montanum, as the large overlap between meadow pairs was consistent with the extensive pollen flow. The smaller flowering overlap among R. bulbosus meadows might explain the slightly more limited pollen flow detected. Conclusions High levels of pollen flow among altitudes in both R. bulbosus and T. montanum should facilitate exchange of genes which may enhance adaptive responses to rapid climate chang

Development of thirteen polymorphic microsatellite markers for the Seychelles endangered and endemic jellyfish tree Medusagyne oppositifolia (Medusagynaceae)

The jellyfish tree Medusagyne oppositifolia is a flagship species of the Seychelles, being not only extremely rare and critically endangered, but also representing a monospecific endemic family, Medusagynaceae. The species survives in four populations on the Island of Mahé, where the total number of reproductive adults is 89. Natural regeneration is only known for the largest of these populations. Understanding the mechanisms driving the lack of natural regeneration in this species has great conservation relevance. We developed thirteen polymorphic microsatellite loci for this species to enable studies of historic and contemporary gene flow. The number of alleles per locus ranged from 2 to 15 (mean of 6.62 per locus) with an average polymorphic information content of 0.54 across loci. Expected heterozygosity ranged from 0.12 to 0.66 with only two of the 13 loci showing deviation from Hardy-Weinberg expectation. The markers will help to provide a better understanding of the significance of historic distributions, gene flow and recent anthropogenic habitat degradation for the in situ and ex-situ conservation of this flagship tree specie

Landscape Composition Has Limited Impact on Local Genetic Structure in Mountain Clover, Trifolium montanum L

Semi-dry grasslands in the European Alps have been increasingly fragmented over the last 150 years. Few studies have investigated the implications of landscape configuration for genetic structure and gene flow among remnant habitat patches. Conservation management of semi-dry grassland plants rarely accounts for possible effects of major landscape elements, such as forest patches, as barriers to gene flow and dispersal via seed and pollen, despite their potential importance for biodiversity conservation. Using 1416 individuals from 61 sampling sites across 2 valleys in South-Eastern Switzerland and Amplified fragment length polymorphism (AFLP) fingerprints, we applied a spatial strip and a circle approach to determine the impact of different landscape elements on genetic differentiation in the semi-dry grassland herb Trifolium montanum (mountain clover). Overall genetic differentiation among sampling sites was low (overall F ST = 0.044). Forest area had no effect on gene flow at the landscape scale, but area of semi-dry grassland, the potential habitat of T. montanum, road area, and altitude influenced genetic differentiation among sampling sites. The observed pattern of genetic differentiation suggests that a future increase in forest area, due to land use abandonment, at least in the short term, are unlikely to directly impact patterns of genetic variation in T. montanu

Development of polymorphic microsatellite markers for the critically endangered and endemic Indian dipterocarp, Vateria indica L. (Dipterocarpaceae)

Vateria indica (Dipterocarpaceae) is an economically and ecologically important canopy tree endemic to the Western Ghats, India. The species has undergone extensive habitat loss and overexploitation and is therefore listed as ‘critically endangered' on the 2012 IUCN Red List. We developed ten polymorphic microsatellite loci for V. indica. In addition, we confirm cross amplification and variation in two loci isolated from the closely related but geographically disjunct species Vateriopsis seychellarum, previously published by Finger et al. Conserv Genet Resour, 2 (S1):309-311, (2010). The twelve microsatellite primers screened on 48 adult samples of V. indica had 5-11 alleles per locus (mean of 8.5 per locus) with an average polymorphic information content of 0.64 across loci. Expected heterozygosity ranged from 0.44 to 0.84. These markers will enable us to quantify population genetic diversity in habitat fragments and to study fine scale spatial genetic structure and contemporary gene flo