Population structure and regeneration pattern of Himalayan birch (Betula utilis D.Don) in the timberline zone of Nanda Devi Biosphere Reserve, Western Himalaya, India

Figures & data

Table 1. General characteristic features of the selected sites of the timberline region of Nanda Devi Biosphere Reserve (NDBR).

Location	Site	Strata	Slope aspect	Site characteristics	Slope angle	Major vegetation type
Valley of Flower, National Park (VoF, NP).	Pure Betula utilis forest	Sub-alpine (3200–3800 m.)	South-West	Avalanches prone area, Slopes with erosion, Stony desert	65–70	Betula utilis, Abies pindrow, Rhododendron campanulatum
			North -East	Avalanches prone area, slope with erosion	70–75	Betula utilis, Rhododendron campanulatum, Abies pindrow, Sorbus foliolosa.
	Mixed Betula utilis forest	Sub-alpine (2800–3200 m.)	South-West	Transitional (Ecotone) zone.	55–65	Betula utilis, Cedrus deodar, Abies pindow, Taxus baccata, Acer caesium, Salix sikkimensis, Rhododendron campanulatum
			North -East	Transitional (Ecotone) zone.	60–65	Betula utilis, Abies pindrow, Cedrus deodara, Taxus baccata, Acer sp, Vibrunum grandiflorum, Sorbus foliolosa, Salix sikkimensis
Nanda Devi, National Park (ND, NP).	Pure Betula utilis forest	Sub-alpine (3500–4200 m.)	South-West	Slopes with dwarf rhododendron, Area with boulders.	65–75	Betula utilis, Abies pindrow, Taxus baccata, Acer caesium
			North-East	Slopes with dwarf rhododendron, Area with boulders.	60–65	Betula utilis, Abies pindrow, Rhododendron campanulatum, Juniperus sp
	Mixed Betula utilis forest	Sub-alpine (3050–3500 m.)	South -West	Transitional (Ecotone) zone.	70	Betula utilis, Abies pindrow,Pinus wallichiana, Salix sikkimensis, Cedrus deodar, Populus ciliata,Picea smithiana, Acer caesium
			North-east	Transitional (Ecotone) zone.	55–70	Betula utilis, Abies pindrow, Cedrus deodara, Pinus wallichiana, Taxus baccata

Table 2. Diversity-dominance parameters in Valley of Flower National Park (VoFNP) and Nanda Devi National Park (NDNP).

Site	Forest feature	Aspects
Valley of Flower		South				North
		Pure Betula utilis forest (3500–4200)		Mix Betula utilis forest (2800–3400)		Pure Betula utilis forest (3500–4200 m)		Mix Betula utilis forest (2800–3400)
		H	CD	H	CD	H	CD	H	CD
	Tree	0.65	0.60	1.16	0.40	0.36	0.82	1.87	0.19
	Sapling	0.83	0.49	1.12	0.39	0.63	0.66	1.88	0.17
	Seedling	0.72	0.53	0.91	0.49	0.88	0.46	1.75	0.21
	Shrub	1.99	0.10	1.35	0.13	2.19	0.13	2.00	0.17
	Herb	2.53	0.02	2.13	0.04	3.47	0.04	2.98	0.07
	Total	6.72	1.73	6.68	1.45	7.53	2.11	10.47	0.82
Tolma region (ND-NP)	Tree	0.83	0.57	1.56	0.27	0.41	0.77	1.21	0.35
	Sapling	1.00	0.43	1.69	0.23	0.91	0.44	1.36	0.30
	Seedling	0.88	0.47	1.52	0.28	0.63	0.62	1.03	0.45
	Shrub	1.54	0.23	2.56	0.08	1.10	0.12	0.96	0.05
	Herb	1.88	0.20	2.50	0.11	2.26	0.44	1.89	0.17
	Total	6.13	1.90	9.83	0.98	5.32	2.39	6.45	1.32

Table 3. North and south aspect of pure and mixed Betula utilis forest of valley of flower National Park.

Species	Pure Betula utilis forest						Mixed Betula utilis forest
	North aspect			South aspect			North aspect			South aspect
	Den.	TBC	IVI	Den.	TBC	IVI	Den.	TBC	IVI	Den.	TBC	IVI
Betula utilis	1254	22.13	266.56	1087	28.61	243.44	663	11.48	136.48	487	17.8	85.68
Abies pindrow	25	8.44	12.48	654	3.22	13.98	226	40.68	72.16	191	11.97	48.69
Rhododdendron campanulatum	125	3.86	13.44	66	5.3	32.28	186	0.98	15.62	162.5	1.7	12.33
Taxus baccata	16	5.6	7.52	-	-	-	16	6.66	7.4	200	8.11	38.93
Acer caesium	-	-	-	12	2.6	10.4	20	7.63	18.89	75	4.77	22.64
Cedrus deodara	-	-	-	-	-	-	1.1	52.64	32.4	179	14.33	63.43
Viburnum grandiflorum	-	-	-	-	-	-	6	5.17	13.24	50	2.1	12.33
Sorbus foliolosa	-	-	-	-	-	-	16	1.05	3.81	37.5	2.29	10.23
Salix skimensis	-	-	-	-	-	-	-	-	-	79	1.39	5.74
Total	1420	40.03	300	1819	39.73	300	1246	126.29	300	1462	64.46	300

Table 4. North and south aspect of pure and mixed Betula utilis forest of Nanda Devi National Park.

Species	Pure Betula utilis forest						Mixed Betula utilis forest
	North aspect			South aspect			North aspect			South aspect
	Den.	TBC	IVI	Den.	TBC	IVI	Den.	TBC	IVI	Den.	TBC	IVI
Betula utilis	1525	22.2	217.31	793	26.8	255.8	854	13.58	114.32	460	19.74	96.11
Abies pindrow	258	12.4	18.3	63	8.8	23.8	400	9.49	54.42	176	24.68	72.54
Taxus baccata	91	3.6	10.17	-	-	-	62	3.88	11.51	36	7.9	21.11
Rhododendron campanulatum	250	4.4	41.62	253	5.2	12	112	2.2	4.53	33	4.37	12.44
Acer caesium	12	1.3	12.6	-	-	-	20	1.53	5.85	6		13.08
Sorbus foliolosa	-	-	-	23	2.6	8.4	-	-	-	-	-	-
Pinus wallichiana	-	-	-	-	-	-	458	34.79	70.53	56	16.71	42.6
Cedrus deodara	-	-	-	-	-	-	100	33.04	7.2	150	14.68	42.12
Picea smithiana	-	-	-	-	-	-	12	8.25	5.46	-	-	-
Populus ciliata	-	-	-	-	-	-	54	3.44	13.65	-	-	-
Salix sikkimensis	-	-	-	-	-	-	70	2.54	12.63	-	-	-
Total	2136	43.9	300	1132	43.4	300	2145	112.74	300.1	920	88.08	300

*Den: Density; TBC: Total basal cover; IVI: Importance value index.

Figure 1. Population structure of pure B. utilis dominated forest; (a) North aspect of VoFNP, (b) South aspect of VoFNP, (c) North aspect of NDNP, (d) South aspect of NDNP.

Figure 2. Population structure of mixed B. utilis dominated forest; (a) North aspect of VoFNP, (b)South aspect of VoFNP, (c) North aspect of NDNP, (d) South aspect of NDNP.