Characteristics of fuels and fire risk among the main forest types in Hoang Lien National Park

on.) Copel., S. palmifolia (Koen) Stapf, 
 Poor forest 41 49 
 Dicranopteris linearis (Burm.f.) Underw., Bidens pilasa 
 San Sa Ho L., Rubus Alceaefolius Poir., Physalis angulata. 
 X. sikkimensis (Hieron.) Copel., D. linearis (Burm.f.) 
 Underw., S. palmifolia (Koen) Stapf, Pogonatherium 
 Rehabilitati
 crinitum (Thunb.) Kunth, Herminium lanceum (Thunb. ex 45 45 
 on forest 
 Sw.) Vuijk., R. Alceaefolius Poir., S. petelotii (A. Camusa) 
 A. Camus, P, angulata, Chromalaena odorata (L.). 
 S. palmifolia (Koen) Stapf, X. sikkimensis (Hieron.) Copel., 
 Dysoxylum tonkinense Chev. ex Pellegr., R. Alceaefolius 
 Medium 
 Poir. (R. moluccanus L), Tradescantia pallida, Psychotria 92 75 
 forest 
 rubra (Lour.) Poir (P. reevesii Wall), M. imbricata Wall. ex 
 C.B. Clarke, Phrynium placentarium... 
 X. sikkimensis (Hieron.) Copel., Dicranopteris linearis 
 Plantation 
 (Burm.f.) Underw., Setaria palmifolia (Koen) Stapf, R. 67 60 
 forest 
 Alceaefolius Poir., C. odorata (L.). 
 S. petelotii (A. Camusa) A. Camus, P. angulata, S. 
 Grassland, palmifolia (Koen) Stapf, M. imbricata Wall. ex C.B. 
 49 71 
 shrubland Clarke, D. linearis (Burm.f.) Underw., X. sikkimensis 
 (Hieron.) Copel 
 D. linearis (Burm.f.) Underw., C. odorata (L.), M. 
 imbricata Wall. ex C.B. Clarke, Piper chaudocanum C. 
 Poor forest 64 41 
 DC, R. Alceaefolius Poir., S. palmifolia (Koen) Stapf, X. 
 sikkimensis (Hieron.) Copel., P. angulata... 
 S. palmifolia (Koen) Stapf, Setaria glauca (L.) P. 
 Beauv., X. sikkimensis (Hieron.) Copel., M. imbricata 
 Rehabilitati
 Wall. ex C.B. Clarke, D. linearis (Burm.f.) Underw., 41 53 
 Ta Van on forest 
 P. angulata, Amomum aromaticum Roxb., R. 
 Alceaefolius Poir. (R.moluccanus L)... 
 X. sikkimensis (Hieron.) Copel., S. palmifolia (Koen) Stapf, 
 Medium 
 M. imbricata Wall. ex C.B. Clarke, D. linearis (Burm.f.) 85 55 
 forest 
 Underw., Psychotria rubra (Lour.), A. aromaticum Roxb. 
 S. petelotii (A. Camusa) A. Camus, Bamboo, S. 
 Bamboo 
 palmifolia (Koen) Stapf, Amomum lacteum Ridl., D. 85 80 
 forest 
 linearis (Burm.f.) Underw., Phrynium placentarium 
 Setaria palmifolia (Koen) Stapf, X. sikkimensis 
 Plantation 
 (Hieron.) Copel., R. Alceaefolius Poir. (R. moluccanus 69 53 
 forest 
 L), A. aromaticum Roxb. 
 Calamus sp., Maesa SP., X. sikkimensis (Hieron.) 
 Rehabilitati Copel., S. palmifolia (Koen) Stapf, M. imbricata Wall. 
 32 45 
 on forest ex C.B. Clarke, Clerodendron infortunatum L, 
 Dysoxylum tonkinense Chev. ex Pellegr.... 
 Ban Ho 
 Sinobambusa sat (Bal.) T.Q. Nguyen Lau, Setaria 
 Grassland, palmifolia (Koen) Stapf, X. sikkimensis (Hieron.) 
 25 30 
 shrubland Copel., Achyranthes aspera L., Bidens pilasa L., S. 
 petelotii (A. Camusa) A. Camus 
 JOURNAL OF FORESTRY SCIENCE AND TECHNOLOGY NO. 2 - 2018 91
 Management of Forest Resources and Environment 
b) Mass and water content of fuels from of its direct effects on the flammable ability, 
forest types emergence and spread speed of forest fires as 
 Mass and water content (relative moisture well as the level of damage caused by the fires. 
content) of fuels is a significant factor because These characteristics are in table 5. 
 Table 5. Mass and water content of fuels from forest types 
 Mass (tons/ha ) 
 Water content 
 Commune Forest type Dried Green 
 Total (%) 
 material material 
 Grassland, shrubland 11.21 11.31 22.52 13.33 
 Poor forest 8.74 10.93 19.67 23.10 
 San Sa Ho Rehabilitation forest 11.04 8.49 19.53 21.31 
 Medium forest 13.99 3.02 17.01 30.41 
 Plantation forest 13.24 6.43 19.67 22.23 
 Grassland, shrubland 11.49 13.10 24.59 14.47 
 Poor forest 7.11 13.30 20.41 21.37 
 Rehabilitation forest 7.35 12.04 19.39 25.66 
 Ta Van 
 Medium forest 6.52 21.61 28.13 32.63 
 Bamboo forest 6.50 8.72 15.22 16.73 
 Plantation forest 13.56 6.98 20.54 24.09 
 Rehabilitation forest 7.52 11.32 18.84 20.65 
 Ban Ho 
 Grassland, shrubland 10.75 12.24 22.99 15.43 
 The results show that water content is quite located in a lower-elevation area or people 
high in medium forests (30.41% in San Sa Ho have planted Amomum aromaticum Roxb. 
commune and 32.63% in Ta Van commune). under the canopy that decrease fire risk to the 
This may be caused by high canopy cover. The medium level. Indeed, A. aromaticum Roxb. is 
canopy layer is capable of partly blocking solar a broad-crown plant that can cover the soil and 
radiations along with the ability of water save water to hold fuel moisture at a moderate 
retaining that make combustible materials on level. 
the ground always of certain moisture. In Table 5 shows that there is a massive 
rehabilitation and poor forests, the content of amount of combustible materials among forest 
water in fuels is average from 20.65% - area. Grasslands, shrublands and medium 
25.66%. forests have the largest mass of fuels (> 20 
 Combustible materials in grasslands and tons/ha) that is very dangerous to forest fire. 
shrublands have average water content at the In other forest types, the amount of fuels is 
lowest level in the study area (13.33% in San medium. However, well-developed 
Sa Ho commune, 14.47% in Ta Van commune understorey layers along with the severe 
and 15.43% in Ban Ho commune). All they are weather condition in the North West (i.e. long 
at high level of fire risk. The understorey periods of dry and hot weather) make the fire 
composition includes flammable plants, such risk here need to be considered. 
as D. linearis (Burm.f.) Underw., C. odorata 3.2.4. Assessment on fire risk of forests and 
(L.) King et Robinson and X. sikkimensis forest lands in Hoang Lien National Park 
(Hieron.) Copel., etc., that push the probability From the analysis in the previous sections, the 
of fire outbreak and spread to a high level if study classified fire risk of studied forest types by 
fire occurs. Most of the plantation forests is standardizing the criteria by the opposite method 
92 JOURNAL OF FORESTRY SCIENCE AND TECHNOLOGY NO. 2 - 2018 
 Management of Forest Resources and Environment 
(Nguyen Hai Tuat, 2010), in which: Criterion 1 is these criteria are defined by expert consultation: 
fuel water content - Wv (%); Criterion 2: fuel coefficient of 0.25 for Criterion 1 and Criterion 2; 
mass - Mv (ton/ha); Criterion 3: height of 0.2 for Criterion 3; and 0.15 for Criterion 4 and 
understorey trees - Hcb (cm); Criterion 4: trunk Criterion 5. The statistics of the criteria are in 
height - Hdc (m); Criterion 5: understorey table 6. 
coverage - CP (%). The weight coefficients of 
 Table 6. Criteria for assessment on fire risk of forests and forest lands 
 Forest type Wv (%) Mv (ton/ha) Hcb (cm) CP (%) Hdc (m) 
 Grassland, shrubland 14.41 23.37 52.0 72.0 0.0 
 Poor forest 22.23 20.41 52.5 45.0 4.5 
 Rehabilitation forest 23.49 19.46 46.2 47.7 4.7 
 Medium forest 31.52 18.10 65.0 80.0 10.6 
 Bamboo forest 16.73 15.22 85.0 80.0 0.0 
 Plantation forest 14.41 20.11 68.0 56.5 3.2 
 The criteria above were standardized by the quantification results are in table 7. 
opposite method to calculate the Ect index. The 
 Table 7. Results of criterion standardization 
 Forest type Wv (%) Mv (ton/ha) Hcb (cm) CP (%) Hdc (m) Ect 
 Grassland, shrubland 0.136 0.250 0.122 0.135 0.150 0.793 
 Poor forest 0.074 0.218 0.124 0.084 0.086 0.689 
 Rehabilitation forest 0.064 0.208 0.109 0.089 0.083 0.553 
 Medium forest 0.000 0.194 0.153 0.150 0.000 0.497 
 Bamboo forest 0.117 0.163 0.200 0.150 0.150 0.780 
 Plantation forest 0.136 0.215 0.160 0.106 0.105 0.721 
 Based on the range of changes in the at low risk (level I). Rich forests with a small 
overall indicator Ect, the study has classified area are classified as level I due to their 
the fire risk into 4 level as below: conditions unsuitable for forest fire. 
 + Level I - Low risk of fire (Ect < 0.55); The results of the classification may also be 
 + Level II - Medium risk of fire (0.55 ≤ Ect relative because forest fires are actually 
< 0.65); influenced by many other factors such as site 
 + Level III - High risk of fire (0.65 ≤ Ect < condition, impact of people, and especially 
0.75); weather. Rehabilitation forests now are only at 
 + Level IV - Extremely high risk of fire (Ect medium level because of high moisture, but 
≥ 0.75). during hot and windy periods, heavy winds can 
 According to the classification: shrublands push the fire risk to the highest level. In reality, 
and grasslands (category Ic) and bamboo forest the burnt areas of regeneration forest is the 
are at highest fire risk (level IV); Plantation largest compared to other forest types because 
forest and evergreen poor forest are at high risk in the subsequent years from fire, these areas 
of fire (level III); Forest without volume is at have been partly counted as regeneration 
medium risk (level II); and evergreen average are forest. 
 JOURNAL OF FORESTRY SCIENCE AND TECHNOLOGY NO. 2 - 2018 93
 Management of Forest Resources and Environment 
3.2.5. Building fire risk map of forest types in have built the fire risk map for the study 
Hoang Lien National Park area. Each level is represented by a single 
 From the fire risk classification, the study color as in fig. 2. 
 FIRE RISK MAP 
 Hoang Lien National Park 
 Fig. 2. Fire risk map of forest types in the study area 
 According to Fig. 2, there is not large area IV. CONCLUSION 
of forest with low fire risk, especially a very - Hoang Lien National Park currently has 
small area of medium and rich forests. These 25,113.66 ha of forest, with the main types as 
forest types are scattered over 4 communes but poor and medium evergreen broad-leaved 
often located in area within strictly protected lowland forest, bamboo forest and plantation 
sub-zones, with rugged terrain or at high forest. There are very small area of natural 
elevation. Plantation forests at high fire risk are rich forest often located in strictly protected 
often located near the national highway from sub-zones. The rest of national park area is 
Sa Pa to Lai Chau province. 2,143.75 ha of bare land with or without 
 The high and very high fire risk forests are regeneration trees. 
scattered throughout all communes in Hoang - From 2009 to 2016, fires damaged 937.85 
Lien National Park. However, the risk is ha of forest in Hoang Lien National Park. 
concentrated in the villages Seo My Ty, Den Forest fire has occured mainly in rehabilitation 
Thang and Seo Trung Ho - Ta Van commune; forest (79.51%), followed by grasslands and 
the villages Ta Trung Ho and Ma Quai Ho - shrublands (14.16%), poor forest (6.15%) and 
Ban Ho commune; and area on Nui Xe plantation forest (0.18%). The fire season is 
mountain (adjacent to Lai Chau) - San Sa Ho during February and March, mainly due to 
commune. These high risk forest types slash-and-burn agriculture, hunting and honey-
concentrate to the North East of the making. Frequent-fire area are concentrated in 
communes. This is where fires occur annually Ban Ho, Ta Van and San Sa Ho communes. 
that prove the high level of fire risk in these - Poor and rehabilitation forests have been 
locations. In addition, there are ethnic greatly influenced; the canopy structure is broken 
minorities living in these areas that is difficult down, the forest cover is at low level (31 - 52%) 
to control sources of fire. facilitating the understorey vegetation layer to 
94 JOURNAL OF FORESTRY SCIENCE AND TECHNOLOGY NO. 2 - 2018 
 Management of Forest Resources and Environment 
well develop. In each forest type, there are forest fire characteristics and other socio-
different vegetation characteristics, thus forming economic factors, to propose solution for forest 
different fuel sources for fire. fire prevention and suppression following 
 - There is a clear difference in fuel scientific and practical bases. 
characteristics among forest types, including REFERENCES 
trunk height, height and coverage of 1. Heikkila T. V., Gronqvist R., Jurvelius R. M. 
understorey trees, mass and moisture of (2010). Wildland Fire Management. Forest Management 
combustible materials. Team, Forestry Department, FAO. Rome. 
 2. Hoang Lien National Park (2014). Adjustment and 
 - Based on characteristics of combustible 
 supplement to the plan for forest fire prevention and 
materials, the study successfully classified forest suppression in the dry season 2014-2015. 
types by fire risk into 4 levels as follows: 3. Hoang Lien National Park (2016). Statistics of 
shrublands and grasslands (category Ic) and forest area in Hoang Lien National Park. 
bamboo forest are at highest fire risk (level IV); 4. Hoang Lien National Park (2017). Report on fire 
Plantation forest and evergreen poor forest are at situation in Hoang Lien National Park. 
high risk of fire (level III); Forest without 5. Nguyen Hai Tuat, Tran Quang Bao, Vu Tien 
 Thinh (2010). Quantitative ecological research methods. 
volume is at medium risk (level II) and evergreen 
 Agriculture publisher, Ha Noi. 
average are at low risk (level I). 6. Vietnam Government (2006). The decree No. 
 From those results, it is necessary to further 09/2006/ND-CP on fire prevention and supppression. 
study on other factors, such as terrain, climate, Ha Noi. 
ĐẶC ĐIỂM VẬT LIỆU VÀ NGUY CƠ CHÁY Ở CÁC TRẠNG THÁI RỪNG 
 CHỦ YẾU TẠI VƯỜN QUỐC GIA HOÀNG LIÊN 
 Trần Minh Cảnh1, Lê Thái Sơn2, Lê Xuân Thắng3 
 1Trường Đại học Hải Dương 
 2Trường Đại học Lâm nghiệp 
 3Vườn Quốc gia Hoàng Liên 
 TÓM TẮT 
 Vườn quốc gia Hoàng Liên hiện quản lý 25.113,66 ha rừng, với các trạng thái chủ yếu: rừng gỗ tự nhiên lá 
 rộng thường xanh nghèo, trung bình, rừng phục hồi, rừng tre nứa và rừng trồng. Rừng tự nhiên giàu hiện còn 
 rất ít, thường phân bố ở phân khu bảo vệ nghiêm ngặt và 2.143,75 ha đất trống không hoặc có cây gỗ tái sinh. 
 Có sự khác nhau khá rõ về đặc điểm vật liệu cháy (VLC) ở các trạng thái rừng, qua những chỉ tiêu gồm: Chiều 
 cao dưới cành tầng cây cao, chiều cao và độ che phủ của lớp thảm tươi cây bụi, khối lượng và độ ẩm VLC. Từ 
 đặc điểm VLC, phân nguy cơ cháy của các trạng thái rừng và trảng cỏ, cây bụi thành 4 cấp theo mức độ nguy 
 hiểm với lửa như sau: trạng thái trảng cỏ cây bụi và rừng tre nứa có nguy cơ cháy cao nhất (cấp IV); trạng thái 
 rừng trồng và rừng thường xanh nghèo có nguy cơ cháy ở mức cao (cấp III); rừng phục hồi có nguy cơ cháy ở 
 mức trung bình (cấp II); rừng thường xanh trung bình và giàu có nguy cơ cháy thấp (cấp I). Từ kết quả phân 
 cấp nguy cơ cháy rừng như trên, xây dựng bản đồ phân cấp nguy cơ cháy cho các trạng thái rừng ở Vườn Quốc 
 gia Hoàng Liên. 
 Từ khóa: Đặc điểm vật liệu cháy, nguy cơ cháy rừng, phòng cháy - chữa cháy rừng, trạng thái rừng, 
 Vườn Quốc gia Hoàng Liên. 
 Received : 07/02/2018 
 Revised : 06/3/2018 
 Accepted : 14/3/2018 
 JOURNAL OF FORESTRY SCIENCE AND TECHNOLOGY NO. 2 - 2018 95