Reforesting Opencast Mines with SCG

FORRU-CMU is collaborating with the Siam Cement Group to develop effective techniques to put back ‘natural’ forest ecosystems on open cast mines in Lampang Province; a lignite mine at Ban Mae Than, Sob Phab District and a limestone mine at Muang Poon, Chae Hom district.

Alstonia scholaris, a promising species on opencast mines.These are extremely challenging sites, with a compacted rocky substrate (no soil), a very hot and dry microclimate and a limited choice of indigenous forest tree species, capable of growing under such conditions. On the plus side, the mines are surrounded by relatively intact native forest, which provides refuge for several seed-dispersing birds and mammals. So the framework species method can potentially be used to attract these animals into restoration plots and thus accelerate biodiversity recovery.

FORRU-CMU has provided advanced training for SCG staff on all aspects of forest restoration, from seed collection in surrounding remnant forest, to tree planting, maintenance and monitoring, as well as research techniques to gather data, both in the nursery and in field trials.

FORRU staff are taking care of baseline biodiversity monitoring (trees, ground flora and birds), whilst SCG staff have established nurseries to grow indigenous tree species from locally collected seed. Trial plots have been established to test both species performance and substrate amelioration methods. Some of the species planted so far are showing promising performance. More details here.

Two CMU research students are testing direct seeding at the mines, as an alternative to tree planting. Ms. Farzana is testing direct seeding of 5 forest tree species at the lignite mine, whilst Mr. Watit is mixing Ficus spp seeds with gel and injecting the slurry into cracks in limestone, to see if fig trees can establish this way. The roots of fig trees can open up rocky substrates to allow oxygen and water to penetrate and thus create conditions suitable for the growth of other trees species.

More Information
1. A booklet on restoring limestone mines - some premilinary advice (English
2. Limestone mine 1st year project report (Thai)

 
      

 

     Direct seeding experiment, planting for 3 months




Education activity at SCG Nursery