Restoring Upland Evergreen Forest at Mon Cham with the Rajapruek Institute Foundation (RIF)

Planting day (21/7/22).This project, sponsored by Rajapruek Institute Foundation (RIF), tested various candidate framework tree species for restoring upland evergreen forest at Mon Cham View Point area (in Doi Suthep-Pui National Park). It expanded the restoration plot system first established there in 2012 (sponsored by PATT). A total of 2,000 trees of 22 species were planted over 10 rai complementing pre-existing natural regeneration that had failed to achieve canopy closure since 2012. After planting, site maintenance (weeding and fertilizer application) was performed for the following 2 rainy seasons.

Furthermore, recovery of biodiversity and carbon storage were assessed comparing 2 and 12 year old restoration plots with a nearby remnant of the original upland evergreen forest (reference forest) and with control site (where no restoration had been implemented).

Tree performance

Monitoring of the planted trees for baseline data (BL) was performed on the end of the first rainy season (R1) and the end of the second rainy season (R2). Root collar diameter (RCD) was measured by Vernier calipers and tree height by tape measure along with crown width at the widest point. A health score was assigned to each tree along with a descriptive note about any health problems observed. Overall survival of planted trees was 96% at the end of the first rainy season and 84% at the end of the second rainy season. 13 of the 22 species tested exceeded 50% of the maximum performance score.R1 monitoring at the end of the first rainy season (26/11/22).

Biodiversity Leopard Cat in the day time, close to a camera trap in the MC12 plot.

Regarding biodiversity monitoring, bird surveys were conducted by direct observation using binoculars and mammals were surveyed by camera trapping. The bird and mammal communities over the entire plot system exhibited high species richness. A total of 125 bird species, representing 40 families (not including 11 unidentified species), were observed over the whole area and all observation periods. Camera trapping showed higher mammal activity in forested plots than in the control. Despite being highly disturbed and fragmented, the area retained at least small to medium sized mammal species including Leopard Cat, Pangolin, Hog Badger, Common Palm Civet, Large Indian Civet and Asiatic Golden Jackal. Asiatic Golden Jackal

Carbon

Carbon monitoring a was performed using 8 circular sampling units in each of four areas: control plot, 2 restored plots and reference forest. Carbon was assessed in three pools: i) trees, by allometric equations, ii) ground vegetation, by weighing dry mass and iii) soil, by analysis of organic matter content. Surveys were performed twice during the project period, just over 14 months apart. Carbon accumulation during restoration was rapid, with levels in the young and old restoration sites attaining 22% and 54% that of reference forest within 2 and 12 years respectively following tree planting. The oldest restored forest (MC12) currently stores 4-5 times more carbon than the control plot.Measuring trees for carbon storage.