Fujian cypress and two other threatened tree species in three conservation zones of a nature reserve in north-western Vietnam

Forest Ecosystems

Table 2 Site conditions and forest structural characteristics of the three conservation zones. Numbers are means and standard deviations, with 40 initial random plots per zone

	Core zone	Buffer zone	Restoration zone
Total study area (ha)	72.8	115.1	21.6
Elevation (m a.s.l.)	1449.1 ± 62.6^a	1363.3 ± 86.7^b	1465.5 ± 91.0^a
Slope inclination (degrees)	39.5 ± 7.7^a	35.9 ± 5.4^b	35.6 ± 5.9^b
Soil pH	4.7 ± 0.4^a	4.7 ± 0.4^a	4.8 ± 0.2^a
Tree density (trees_≥6cm; trees∙ha⁻¹)	925 ± 251^a	1006 ± 357^a	1660 ± 387^b
DBH (trees_≥6cm; cm)	21.4 ± 3.4^a	16.6 ± 3.0^b	12.8 ± 1.4^c
Basal area (trees_≥6cm; m²∙ha⁻¹)	52.9 ± 21.4^a	30.4 ± 15.4^b	24.8 ± 5.9^c
Canopy closure (%)	88.4 ± 7.2^a	84.5 ± 9.4^b	81.3 ± 6.4^c
Observed species richness (trees_≥6cm, sp. per 40 plots)	193	173	135
Mean species richness (trees_≥6cm, sp. per plot)	22.1 ± 5.1^a	19.3 ± 5.9^b	16.8 ± 5.0^c
Observed red-listed species richness (trees_≥6cm, sp. per 40 plots)	16	10	5
Stumps (no. per plot)	0.6 ± 0.8^a	1.6 ± 1.6 ^b	1.7 ± 1.4^b
Footpaths (no. per plot)	0.9 ± 0.6^a	1.5 ± 0.8^b	1.1 ± 0.9^a,b

Significant differences in the means of three conservation zones at the level of p ≤ 0.05 were indicated in different superscript letters