Southeast Asian forests are among the most species rich in the world and are an important source of timber. However, these forests have been severely deforested and more than 70% of remaining forests are degraded. The future of these forests relies on successful regeneration, particularly in human-modified landscapes. Therefore, the aim of this study was to investigate the constraints on reproduction of trees in the Dipterocarpaceae family, which dominate lowland forests in Southeast Asia. Specifically, I aimed to understand the influence of flowering intensity, disturbance history, and genetic diversity of offspring. The proportion of flowers pollinated was higher in larger flowering events for three of the seven species investigated suggesting that flowering intensity may influence pollination. However, further research is required to clarify these results and should include other factors that influence pollination. Disturbance did not negatively affect reproduction in the two species investigated. Parashorea tomentella trees in the disturbed forest produced more flowers (per m2) but had (12%) lower pollination success. However, there was no difference in viable fruit production or seedling establishment. Shorea xanthophylla trees in the disturbed forest produced more flowers (per tree and per m2) and despite having (3%) lower pollination success produced more viable fruit and established more seedlings. My findings indicate that reproduction of some species might be resilient to some types of disturbance and suggest that disturbance to these forests is not used as a pretext to convert them to other land-uses. Finally, the multi-locus heterozygosity (genetic diversity) of offspring was positively related to seedling survival, but did not influence germination or growth. The effect of MLH on survival was greatest in the forest, suggesting that inbreeding depression is stronger under natural growing conditions. Therefore seedlings grown under forest conditions may make better candidates for restoration projects than those grown in a nursery.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:582716 |
| Date | January 2013 |
| Creators | Nutt, Kirsty |
| Publisher | University of Aberdeen |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=201963 |
Page generated in 0.0016 seconds