s.l., plot N1 at 1850 m a.s.l.). The flora of Mt Rorekautimbu is known from the floristic studies of van Balgooy and Tantra (1986) who explored the mountain slope starting from 1700 m up to the summit at 2450 m elevation. They described species-rich Fagaceae–Myrtaceae and Agathis forests at 1700–2000 m a.s.l., but these have been largely deforested since then and only the upper montane crest has remained old-growth. The upper montane old-growth forest remnants HTS assay with large amounts of moss on the forest floor and the trees (‘mossy forest’) at Mt Rorekautimbu were investigated at c. 2400 m elevation (plot R1 at 2350 m a.s.l., plot R2 at 2380 m a.s.l.). The soil types were histic cambisols (FAO 2006) developed

on granite Veliparib chemical structure rock on level terrain on gently sloping ridges or mid-slope terraces. Both sites were characterised by a perhumid climate with at most 2 months per year receiving less than 100 mm rainfall (WorldClim 2006), and with mean annual temperature of 17.9°C in the mid-montane and of 14.1°C in the upper montane forests. Fig. 1 a The study area (star) in Sulawesi, Indonesia, in the centre of the phytogeographical region Malesia which includes nine subdivisions from Malaya to Papuasia (after Brummitt 2001), b location of the study sites at Mt Rorekautimbu (R, plots R1, R2, c. 2400 m

a.s.l.) and Mt Nokilalaki (N, plots N2, N1, c. 1800 m a.s.l.), Lore Lindu National Park (LLNP); grey areas Selleckchem FRAX597 indicate montane elevations >1000 m a.s.l., and climate diagrams of c Mt Rorekatutimbu and d Mt Nokilalaki; climate data extracted from the WorldClim model (Hijmans et al. 2005; WorldClim 2006). Maps with universal transverse mercator (UTM) projection 51 south (WGS Tyrosine-protein kinase BLK 1984) Field sampling Plot-based tree inventories were carried out from July to August 2007. Plot size was 40 × 60 m (0.24 ha) divided up into a 10 × 10 m grid. All trees of diameter at breast height (d.b.h.

at 1.3 m) ≥10 cm were surveyed. Within each of the 10 × 10 m, one 5 × 5 m-sized subplot was surveyed (0.06 ha per plot) to additionally study understorey trees of d.b.h. 2–9.9 cm. All trees were permanently tagged, pre-identified and structural parameters recorded (d.b.h., total height). At both mountains, two plots were installed at about 1000 m distance from each other, i.e. 0.48 ha were sampled in each forest type. Rarefaction analysis (Gotelli and Colwell 2001) confirmed that the area was sufficiently large to represent the species pool at both sites (Culmsee et al. 2010). Tree species identification Tree species identification was based on about 1000 specimens collected from tagged trees and supplementary trees in flower or fruit. Specimens were deposited at the herbaria of Göttingen (GOET), Palu (CEB), Leiden (L) and London (K). The identification was carried out by the first author using the collection of the National Herbarium of the Netherlands (L) as a reference. M.J.E. Coode (K) identified the species within Elaeocarpaceae.