Germination of Ficus microcarpa on limestone for restoring mines

ABSTRACT: For limestone mining in Thailand, it is stipulated that the site must be reclaimed to the original vegetation after mining is completed. The study area was the Muang Poon semi-opencast limestone mine, operated by Siam Cement Group in Lampang Province, northern Thailand. Forest restoration is hindered by no top soil and the stony nature of the mine substrate. I hypothesized that Ficus microcarpa should be able to grow in the limestone mine and facilitate forest restoration because, its strong root system can penetrate and break up the mine substrate and because it is the keystone species in tropical forests in northern Thailand, and should attract seed-dispersing animals into the mine. This project therefore tested germination of Ficus microcarpa using hydrogel for successful in reclamation. For this research. germination was tested in a nursery on substrate gathered from the mine. The experiment was a randomized complete replicate for 5 treatments; i.e, control (seeds sown without hydrogel or additives), hydrogel (H), hydrogel with slow release fertilizer (14-14-14) (HFe), hydrogel with fungicide (HFu) and, hydrogel with slow release fertilizer and fungicide (HFeFu). Highest survival rate (34.5%) was achieved with the HFeFu treatment, whilst lowest survival occurred with the control (19%). Germination percent for the H. HFe, and Hfu treatments were (25%, 28.5%, and 27%, respectively). Differences among treatments were not significant (ANOVA, p<0.05). In conclusion, Ficus microcarpa has potential for direct seeding to establish fig trees on mine sites and that hydrogel may increase success.