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Ba Na Nature Reserve 1996 Verbenaceae - - - - - - 2.85 1 0.42 1 Most of the study sites shared a high proportion of their woody taxa. Even the least disturbed areas of forest contained early successional species such as Xylopia sp., Drimycarpus sp. and Cratoxylon sp. (sometimes present as large trees), suggesting that the entire area has been subject to human disturbance over a long period. 5.2.1.1 Forest Transect 1 (Highly disturbed) Forest Transect 1 was the closest transect to the base camp, at an altitude of 430m. Many of the trees present in the transect were small (this transect had the highest density of trees; see Table 1), and the forest was regenerating after logging. Three canopy layers were evident; the upper canopy, lower canopy and shrub/herb layer. The upper canopy was not complete, due to the past logging of the site. Occasional trees reached 25m, although the majority were around 20m tall. Important families in this layer were the Fagaceae (Castanopsis sp.), Euphorbiaceae (Antidesma and Bridelia spp.), Juglandaceae (Engelhardtia sp.), and Mimosaceae (Pithecolobium sp.). The Dipterocarpaceae (a family containing highly valued timber trees, such as Hopea and Dipterocarpus) were rare (only 10 trees per hectare). The lower canopy (5-15m) was dense, and was dominated by early-successional species such as Xanthophyllum sp. (Polygalaceae) and Xylopia vielana (Annonaceae). The Myrtaceae (Syzygium sp.), Anacardiaceae (Drimycarpus sp.) and Simaroubaceae (Eurycoma longifolia) were also represented, although less abundant. The presence of many early successional species, occasionally as large trees, is a result of disturbance to this site. The Euphorbiaceae, a family containg many early-successional trees such as Croton spp. made up 12% of the total tree basal area in the plot; some of the largest trees present belonged to this family, which also made up a significant proportion of the lower canopy. 5.2.1.2 Forest Transect 2 (Less disturbed) Forest Transect 2 was close to FT1, but further from the base camp, at an altitude of 380m. Tree diversity (in terms of the number of genera represented in the plot) was higher here than at FT1, and the upper canopy was more complete (see Appendix 2(b)), with many large trees (and fewer individuals than FT1). However, the largest trees still only reached around 20m. Amongst the important species of the upper canopy, the family Dipterocarpaceae were represented by Dipterocarpus retusus and Hopea pierrei. Other families represented in the upper canopy included Anacardiaceae (Drimycarpus sp.), Euphorbiaceae (Croton spp.), and Fagaceae (Lithocarpus sp.). The lower canopy was less complete than at FT1, and was dominated by the Symplocaceae (Symplocos sp.), Myrtaceae (Syzygium sp.), Tiliaceae (Microcos paniculata), and Euphorbiaceae (Croton, Endospermum and Macaranga spp.).Bamboos were present in the understorey. The presence of early successional species both in the lower and upper canopies suggests that disturbance has occurred here, although less recently than at FT1, and the plot was in the process of recovery from selective logging. 5.2.1.3 Forest Transect 3 (High altitude) The highest slopes of Ba Na Mountain are covered in montane rainforest (see 5.3.3), but unfortunately this was largely inaccessible due to the steep slopes in this area. However, the site chosen for Forest Transect 3, at 1180m, was in an intermediate zone of Lower Montane Forest, which showed characteristics of both the lowland rainforest and the montane rainforest above. The site chosen was beside the French Road to Ba Na summit, built around 1919 (now an overgrown track). At this altitude, the ruins of villas from the French period were present beside Frontier- Vietnam Environment Research Report 7 10
Ba Na Nature Reserve 1996 the road, and it is probable that the forest within this transect was severely disturbed or even clear-felled at that time, despite the steep slope on which it stands (around 45 o ). The floral composition of Forest Transect 3 differed radically from the other sites, containing a higher proportion of trees of the families Fagaceae and Lauraceae than the lowland plots. There were representatives of families totally absent from the other transects studied, the Magnoliaceae and Podocarpaceae. Some groups typical of the lowland forests (such as the Dipterocarpaceae and Moraceae) were completely absent at these elevations; in all, eight families were present in all transects except for FT3. The Euphorbiaceae, important in the lowland forest sites, was less important at FT3. The structure of the forest at FT3 was also distinctive when compared to the lowland forests studied (which were all below 500m above sea level). FT3 had fewer trees per hectare than the other transects, and stratification of the canopy was less clear here. The upper canopy at FT3 reached around 15-20m, with occasional taller trees to 25m. This layer was dominated by the family Fagaceae (Castanopsis sp.). The Myrtaceae (Trystania sp.) and Podocarpaceae (Podocarpus sp.) were also represented. Because the upper canopy was dense, casting a heavy shade, this plot had fewer trees in the lower canopy. The lower canopy contained a greater variety of families than the upper canopy, however (it was less clearly dominated by the Fagaceae); in addition to those genera already listed, it contained Symplocos sp. (Symplocaceae), Elaeocarpus sp. (Elaeocarpaceae), Cryptocaria sp. (Lauraceae), and Xylopia vielana (Annonaceae). 5.2.1.4 Forest Transect 4 (Highly disturbed) Forest Transect 4 was at an altitude of 380m. It was the most recently disturbed forest plot studied, having been logged 5-10 years previously. As would be predicted, this transect contained a large number of small trees. Surprisingly, however, it also showed highest diversity (in terms of number of tree genera represented; see Table 1). This may reflect the selective nature of the felling carried out on the site. As a result, some old forest trees as well as young trees of pioneer species were found in this locality, contributing to high biological diversity and higher than expected structural diversity. The profile (Appendix 2 (d)) was dominated by an old fig tree (Moraceae; Ficus sp.) which had escaped felling. Other families represented in the upper canopy included the Anacardiaceae (Drimycarpus sp.), Clusiaceae (Garcinia sp.), Ixonanthaceae (Ixonanthes cochinchinensis), Sapotaceae (Sarcosperma sp.), and Caesalpiniaceae (Peltophorum ferrugineum). The Dipterocarpaceae were rare (probably having been removed by logging). The lower canopy was dominated by the Fagaceae (Lithocarpus sp.), Lauraceae (Machilus and Cryptocaria spp.), Rubiaceae (Randia sp.), and Juglandaceae (Engelhardtia spp.). 5.2.1.5 Forest Transect 5 (Least disturbed) Structurally, Forest Transect 5 (at an altitude of 480m) resembled primary forest or old secondary growth more closely than any of the other transects studied. However, it was evident from several large tree stumps, and its proximity to the Forestry Enterprise logging road, that the forest had been recently disturbed (in view of the area's history of disturbance, it seems unlikely that primary forest remains; see 5.3.5). Large forest trees were still present (some with epiphytes, including Asplenium nidus and Platycerium sp. attached); the upper canopy reached 20m.The upper canopy was dominated by the Anacardiaceae (Drimycarpus sp.), Fagaceae (Lithocarpus sp.), and Myrtaceae (Syzygium sp.). There were also occasional large individuals of Vatica tonkinensis (Dipterocarpaceae). The Dipterocarpaceae were abundant (27 trees in the transect, 135 per hectare), but small trees were far more common than mature specimens, suggesting that logging had removed the larger trees. The presence of mature pioneer trees of genera such as Drimycarpus, Cratoxylon, and Xylopia also suggested some disturbance had occurred here. Frontier- Vietnam Environment Research Report 7 11
Page 1: Frontier Vietnam Environmental Rese
Page 4 and 5: Ba Na Nature Reserve 1996 Technical
Page 6 and 7: Ba Na Nature Reserve 1996 TABLE OF
Page 8 and 9: Ba Na Nature Reserve 1996 LIST OF T
Page 10 and 11: Ba Na Nature Reserve 1996 Executive
Page 12 and 13: Ba Na Nature Reserve 1996 ACKNOWLED
Page 14 and 15: Ba Na Nature Reserve 1996 2.0 AIMS
Page 16 and 17: Ba Na Nature Reserve 1996 Figure 2.
Page 18 and 19: Ba Na Nature Reserve 1996 4.0 WORK
Page 20 and 21: Ba Na Nature Reserve 1996 5.2 Resul
Page 24 and 25: Ba Na Nature Reserve 1996 The lower
Page 26 and 27: Ba Na Nature Reserve 1996 5.4 Flori
Page 28 and 29: Ba Na Nature Reserve 1996 6.2 Resul
Page 30 and 31: Ba Na Nature Reserve 1996 100% 90%
Page 32 and 33: Ba Na Nature Reserve 1996 Each 1km
Page 34 and 35: Ba Na Nature Reserve 1996 25 20 % 1
Page 36 and 37: Ba Na Nature Reserve 1996 8.0 FISH
Page 38 and 39: Ba Na Nature Reserve 1996 1.4 1.2 1
Page 40 and 41: Ba Na Nature Reserve 1996 10.0 BIRD
Page 42 and 43: Ba Na Nature Reserve 1996 11.0 MAMM
Page 44 and 45: Ba Na Nature Reserve 1996 12.0 HUMA
Page 46 and 47: Ba Na Nature Reserve 1996 13.0 GENE
Page 48 and 49: Ba Na Nature Reserve 1996 14.0 REFE
Page 50 and 51: Ba Na Nature Reserve 1996 Southwood
Page 52 and 53: 23 Swintonia sp. S Fl,Fr O,T 24 Tox
Page 54 and 55: 30. Connaraceae 106 Connarus cochin
Page 56 and 57: 45. Illiciaceae 199 Illicium sp. P
Page 58 and 59: 289 Rhodomyrtus tomentosa Fl 290 Sy
Page 60 and 61: 86. Solanaceae 373 Physalis angulat
Page 62 and 63: 457 Pandanus gressitii 109. Poaceae
Page 64 and 65: Podocarpaceae; Dacrydium pierrei (D
Page 66 and 67: Family Nymphalidae cont. Family Sat
Page 68 and 69: APPENDIX 4 FISH SPECIES RECORDED AT
Page 70 and 71: Perciformes Family Anabantidae 29)
Page 72 and 73:
APPENDIX 6 REPTILE SPECIES RECORDED
Page 74 and 75:
14. Vernal Hanging-parrot (Loriculu
Page 76 and 77:
85. Oriental Magpie-robin (Copsychu
Page 78 and 79:
APPENDIX 8 MAMMAL SPECIES RECORDED
Page 80:
APPENDIX 9 SPECIMENS COLLECTED AT B
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