1.1.3 Present situation of the growing stock
A summary of the growing stock information for the inventoried forest areas in Sarawak is given in the following table based on (4) and (11). Net industrial stemwood volume (NIS) corresponds to the volume of the free boles of the trees more than 45.7 cm (18 inches) diameter after deducting the cull arising from external and internal defects.
Summary of growing stock data for the inventoried areas
Forest type | Year of inventory | Area in thousand ha (acres) | Volume/unit area m3/ha (HT/acre) | Total growing stock in million m3 (million HT) | Remarks |
Mixed dipterocarp | |||||
FAO Project | 1973 | 1060 (2620) | 133.1 (29.9) | 141.1 (78.5) | NIS volume of all species |
91.9 (20.6) | 97.4 (54.1) | NIS volume of dipterocarp species only | |||
Forest Dept. | 1977 | 475 (1173) | 77.0 (17.3) | 36.5 (20.3) | NIS volume of species class 1–3 |
111.2 (25.0) | 54.5 (30.3) | NIS volume of species class 1–5 | |||
Peat swamp | 1979 | 691 (1707) | 88.7 (19.9) | 612.7 (34.0) | NIS volume of all species |
68.2 (15.3) | 47.2 (26.2) | NIS volume of species class 1–3 | |||
16.5 (3.7) | 11.4 (6.4) | NIS of ramin only | |||
Mangrove | 1977 | 162 (400) | 20.4 (4.6) | 3.3 (1.8) | Not specified |
Keranga | 1973 | 26 (65) | 34.0 (7.6) | 0.8 (0.5) | NIS volume of all species |
The following remarks are necessary:
most of the inventories are restricted to the permanent forests. They cover nearly all of the swamp forests but only ⅔ of the hill forests. Therefore, a reliable statement on growing stock can be made for the permanent forests only;
FAO inventory of the mixed dipterocarp forests reveals that the composition of forests in the medium and high volume strata (which constitutes 85.6 percent of the total inventory area) is rather uniform. A representative stand table taken from the unit 4 of the FAO projet quoted in (9) is given for information:
Stand table of undisturbed mixed dipterocarp forests
Diameter class | Number of stems per ha | ||
in | cm | All species | Dipterocarps |
8–12 | 20–30 | 94.1 | 31.5 |
12–18 | 30–46 | 64.5 | 24.8 |
18–24 | 46–61 | 24.0 | 12.9 |
24–36 | 61–91 | 15.1 | 10.9 |
36–48 | 91–122 | 2.1 | 1.8 |
48+ | 122+ | .2 | .2 |
Total 20 + | 200.0 | 82.1 | |
Total 20–80 | 192.2 | 76.1 | |
Total 80 + | 7.9 | 6.0 |
As mentioned earlier the average log yield per ha obtained from the mixed dipterocarp forests varies from 67 to 89 m3/ha (8). According to a FAO case study (2) made in 1972–73, the average yield per ha was 72 m3. FAO reports (9) and (12), however, indicate a much lighter logging intensity around 7.2 trees/ha. Assuming an average net volume of 4.3 m3/tree, the extracted volume comes to 31 m3/ha only. For the present report an average yield of 75 m3/ha has been assumed since the lower figure does not take into account the yield of a second cut which may occur little after the first harvesting nor the yield per unit area from the forest logged heavily before its transfer for agricultural purposes.
A heavy wastage is reported during logging. The following table based on (9) is intended to illustrate the damage to standing growth.
After logging stand table for Sarawak by damage and size classes
Category | Size classes (girth in ft and diameter in cm) | Total | Total | |||||
2–3 | 3–4 | 4–5 | 5–6 | 2–6 | % | > 6 ft | ||
19–29 | 29–39 | 39–49 | 49–58 | 19–58 | > 58 cm | |||
No damage | 10.7 | 3.4 | 4.0 | 4.3 | 22.4 | 58.1 | 5.1 | 27.5 |
Stem injury | 2.2 | 1.0 | 1.0 | .8 | 5.0 | 13.0 | 2.0 | 7.0 |
Crown injury | 1.6 | 1.6 | .4 | .2 | 3.8 | 9.9 | .6 | 4.4 |
Both types | 1.4 | .4 | 1.8 | 4.7 | .6 | 2.4 | ||
Standing trees | 15.9 | 6.4 | 5.4 | 5.3 | 33.0 | 85.7 | 8.3 | 41.3 |
Broken | .8 | .8 | .6 | 2.2 | 5.7 | 2.2 | ||
Missing trees | 2.8 | .5 | 3.3 | 8.6 | 3.3 | |||
Total | 19.5 | 7.7 | 6.0 | 5.3 | 38.5 | 100.0 | 8.3 | 46.8 |
Using the above stand table and the growth data of Sabah, a projection of diameter of the standing trees over a period of 30 and 40 years under alternative assumption of mortality rates of viz. 1% and 2% per year respectively has been made in (9). The starting and ending stem distributions are as follows:
Projected stand table over 30 and 40 year periods
Year | Size class (cm) | vol. over 58 cm. | M.A.I over 58 cm | ||||||||
19–20 | 29–39 | 39–49 | 49–58 | 58–68 | 68–78 | 78–87 | 87–97 | 97–107 | |||
(1) Mortality 1%/year | |||||||||||
Year 0 | 10.7 | 3.4 | 4.0 | 4.3 | 5.1 | ||||||
Year 30 | 7.91 | 2.51 | 2.96 | 3.18 | 3.77 | ||||||
Merch volume | 11.0 | 18.1 | 24.8 | 36.2 | 90.1 | 2.3 | |||||
Year 40 | 7.15 | 2.27 | 2.68 | 2.88 | 3.41 | ||||||
Merch volume | 31.5 | 13.8 | 20.9 | 27.6 | 38.5 | 132.3 | 2.7 | ||||
(2) Mortality 2%/year | |||||||||||
Year 30 | 5.89 | 1.87 | 2.20 | 2.37 | 2.81 | ||||||
Merch volume | 8.2 | 13.4 | 18.5 | 27.0 | 67.1 | 1.5 | |||||
Year 40 | 4.82 | 1.53 | 1.80 | 1.94 | 2.30 | ||||||
Merch volume | 21.2 | 9.3 | 14.0 | 18.6 | 26.0 | 89.1 | 1.7 |
The M.A.I. of volume of merchantable species over 58 cm DBH and with a 40 year felling cycle and a mortality rate of 2% is 1.7 m3/year/ha.
Keeping the above data in view, the estimated growing stock by the end of 1980 is given in the following table:
Growing stock estimated at end 1980
(totals in million m3)
Forest type | NHCf1uv | NHCf1uc | NHCf1m | NHCf2 | ||||||||
VOB | VAC | VOB | VOB | AAC | VOB | |||||||
m3/ha | total | m3/ha | total | m3/ha | total | m3/ha | total | m3/ha | total | m3/ha | total | |
Mixed dipterocarp | 266 | 1017 | 75 | 287 | 233 | 317 | 2.2 | 3.0 | 133 | 177 | ||
Peat swamp | 85 | 58 | 177 | 120 | 1.5 | 1.0 | 85 | 0.4 | ||||
Mangrove | 41 | 7.2 | ||||||||||
Keranga | 287 | 68 | 24.8 | |||||||||
Total | - | 1017 | - | 287 | - | 58 | - | 437 | - | 4.0 | - | 20.9 |
The following remarks are necessary:
three conversion factors have to be applied to express the figures of NIS volume/ha generally used in Sarawak into volume over bark of the boles of all trees more than 10 cm DBH, here termed as VOB. The NIS has to be expressed as total stem volume under bark (TS) which is gross volume including sound and defect volume. According to (3) the ratio TS/NIS is approximately 1.30. Here the TS volume refers to trees more than or equal to 45 cm diameter (or 18" o.b.). For accounting the volume of trees down to 10 cm diameter a factor of 1.45, based on the observations made in the case of tropical rain forest inventories of India and Nigeria has been used. Finally the underbark volume has been converted into over bark volume. A factor of 1.08 has been used for this purpose. This is based on observations made in the case of other forest inventories in similar conditions. The composite of above factors gives a value almost exactly equal to 2.0;
in the case of managed forest (NHCf1m) the NIS volume has been reduced by 12.5%, as compared to the volume/ha of virgin forest, before the application of above multiplication factor. This is based on taking weighted average of NIS volume in the hitherto exploited and unexploited managed forets. The area of exploited managed forest is given in section 1.1.2;
as already mentioned a value of 75 m3/ha has been assumed for estimating the volume actually commercialized, termed here as VAC. Before multiplying with this, the area of all forest categories concerned is reduced by 15% to account for unstocked forests. This is based on (4);
in case of the logged over forests (NHCf1uc) VOB/ha is assumed to be half of the virgin forests (NHCf1uv);
calculation of annual allowable out (AAC) for the managed forests is rather complex. The present working of the mixed dipterocarp forests is based on a 25 year cutting cycle and 45 cm minimum cutting diameter. There is, however, no special reason to keep the same cycle for the converted crop as the one used presently. Moreover, at the second cycle of felling, the utilization pattern of forest is also likely to undergo changes. Keeping in view the present level of cutting in the managed forests and the likely future growth, Nicholson (9) recommends a felling cycle of 40 years for the worked mixed dipterocarp forests at Sarawak. Projected stand tables and the estimated merchantable volume over 58 cm diameter assuming a 40 year cycle and 2% mortality rate, as was presented earlier in this section is 89 m3/ha. This was for untreated stands. A silvicultural treatment is expected to increase the volume production of stands by been about 60%. For the present calculation of AAC, however, the growth has assumed as 89 m3/ha namely that predicted for untreated stands;
in the case of peat swamp forests, the AAC has been estimated by assuming a growth figure of 60 m3/ha assuming a felling cycle of 40 years.
1.2 Plantations
Plantations in Sarawak are still in the trial stages. Studies are being undertaken on planting of high-valued timber species in logged over forests, elimination trials on Eucalyptus and provenance trials of fast growing species (pines and hardwood).
2. Present trends
2.1 Natural woody vegetation
2.1.1 Deforestation
According to the official land-use of the mid-sixties, 76.5 percent (9.4 million ha) of the total land area (i.e. 12.3 million ha) was forest land and 23.5 percent (2.9 million ha) non-forest land.
A land suitability survey was carried out around 1970 to assess the possibilities of further agriculture development. According to the FAO report (4) “most of the forested land which has been identified as suitable or marginally suitable for agriculture (i.e. 2.6 million ha in addition to the 2.5 million ha already used by agriculture in the mid-sixties) lies on the coastal plain of north Sarawak, between the towns of Bintulu and Miri. The greater part of this forest has been licensed and harvested in anticipation of the large scale development of agriculture which is now being initiated”.
At present it is not precisely known as to how much of the forests lands suitable or marginally suitable for agriculture have been logged over and as to how much has already been brought under permanent or shifting cultivation. According to the 1976 statistics of the Land and Survey Department, there is an increase of area of 500 000 ha in the non-forest land as compared to 1966, or an annual deforestation rate of 50 000 hectares during 1965–76.
For this study calculations have been made correlating the increase of shifting cultivation area with the population growth. The main assumptions made are:
average rate of increase of population of the shifting cultivators is the same as that of the whole population;
area under shifting cultivation increases in proportion to increase of population of shifting cultivators, provided suitable land is available.
Based on the above assumptions, the following figures were arrived at:
Year | Population (in thousand) | Increase over past period | Shifting cultivation area | Remarks | ||
in thousand ha | (in thousand acres) | |||||
1965 | 860 | 1.0 | ) | 2297 | (5676) | actual (FAO 1973) |
1970 | 975 | 1.13 | )1.28 | 2586 | (6415) | estimated |
1975 | 1100 | 1.13 | ) | 2933 | (7247) | estimated |
1980 | 1250 | 1.13 | 3314 | (8189) | projected | |
1985 | 1405 | 1.13 | 3745 | (9254) | projected |
The net area increase under shifting cultivation between 1975 and 1980 is, therefore, estimated as 381 000 ha. The annual report of the Forest Department (5) cites the following data on shifting cultivation in Sarawak from a case study carried out in 1975–76;
Year | Shifting cultivation area | Increase over past period | |
ha | (acres) | ||
1965 | 30987 | (76569) | |
1975/76 | 38829 | (95945) | 1.25 |
The increase over the past 11 years is rather close to the figure calculated above. The projections made above give an annual rate of deforestation of 76 000 ha during 1975–80 and 86 000 ha during 1980–85. Obviously, the shifting cultivation area cannot go on indefinitely increasing. Main limiting factor will be further availability of suitable areas. As mentioned earlier the area suitable or marginally suitable for agriculture as mapped by the Land and Survey Department, in addition to the area already occupied by agriculture in the mid-sixties, is of the order of 2.6 million ha. This fact may be kept in view while making any projections beyond 1985. Moreover, part of the current or projected areas under shifting cultivation may, in fact, be used for extensive or intensive permanent agriculture.
Keeping in view the above data, the figures for the rates of change during 1976–80 and 1981–85 are estimated as follows:
Average annual deforestation 1
(in thousand ha)
Periods | ||||||||||
1976–80 | 1981–85 (projections) | |||||||||
NHCf1.v 1 | NHCf1.c 1 | NHCf1 | NHCf2 | NHCf | NHCf1.v 1 | NHCf1.c 1 | NHCf1 | NHCf2 | NHCf | |
25 | 51 | 76 | 4 | 80 | 28 | 57 | 85 | 4 | 89 |
Some comments are required on the table:
there is an increase in the annual deforestation rate during 1981–85 as compared to 1976–80. This is mainly on account of land speculation mentioned earlier;
about one third of the total area deforested is attributed to clearing of virgin forests for shifting cultivation. In such a case there is no utilization of timber before felling. The rest of deforestation (for shifting or permanent cultivation) is assumed to take place in the already logged over areas.
2.1.2 Degradation
According to the official statistics there are 2.25 million hectares of shifting cultivation and 0.17 million hectares of unused land in the non-forest land. The FAO report (4) based on available data at that time, estimated that only 1.3 million hectares were actually under various cycles of shifting cultivation; the rest, viz. 0.95 million hectares, was lying unproductive and represented exhausted soils. Presumably, the origin of unused land could also be traced to a long period of past shifting cultivation. Similar degradation must be taking place in shifting cultivation areas inside the forest land. There is, however, no precise estimate available on this.
Studies (9) show that after logging 22 percent and 12 percent of land area are classed as “temporary open space” and “bare soils exposed by logging”. The latter category is directly comparable with “tractor paths” and “landings”. The temporary open space by definition is devoid of trees but as it does have top soil, very often it will carry a stocking of dipterocarp seedlings. These data were taken from an area on which 7.2 trees/ha were cut. Thus it appears that current exploitation and resulting damage are still within acceptable limits in Sarawak.
The damage to existing natural vegetation due to logging has already been given in section 1.1.3.
2.1.3 Trends in forest utilization
It has been projected in (8) that log yield by 1985 would be in the order of 7.2 million m3 (4 million HT) as compared to 6.0 million m3 (3.3 million HT) in 1978, which looks a realistic assumption in view of the past trend of log production given in section 1.1.2. The annual harvesting area, therefore, has to be stepped up. Assuming the yield to be 75 m3/ha, this would require a net annual logging area of the size of 96 000 ha or a gross annual area of the size of 110 000 ha.
In view of the conversion of land to permanent/shifting cultivation, presumably only part of the total yield originates from the areas under working/felling plans actually earmarked for utilization. Based on the past trend of forest utilization, it is estimated that 350 000 ha of area would be worked under working/felling plans of the Forest Department compared to 286 000 ha during 1975–80.
2.1.4 Areas and growing stock at end 1985
The trends indicated in the previous sections, used with the data of 1980, lead to the following estimates of area and growing stock for 1985:
Areas of natural woody vegetation estimated at end 1985
(in thousand ha)
NHCf1uv | NHCf1uc 1 | NHCf1m | NHCf1 | NHCf2i | NHCf2r | NHCf2 | NHCf | NHCa | |
Forest land | |||||||||
Mixed dipterocarp | 3070 | 1690 | 4760 | 1230 | 90 | 1320 | 6080 | 1450 | |
Peat swamp | 680 | 680 | 1360 | 5 | 5 | 1370 | |||
Mangrove | 170 | 170 | 170 | ||||||
Keranga | 360 | 360 | 360 | ||||||
Non forest land 2 | 2420 | ||||||||
Total | 3070 | 680 | 2370 | 6120 | 1760 | 95 | 1855 | 7975 | 3870 |
1 In the table there is no increase of logged-over areas as compared to 1980, because there is transfer of such lands to permanent or shifting agriculture. The logged-over areas under prescription of working plan do not show up here because they are included in the category NHCf1m.
2 This includes shifting cultivation and unused land classified as non-forest land by the Forest Department.
Growing stock estimated at end 1985
(in million m3)
Category | NHCf1uv | NHCf1uc | NHCf1m | NHCf1 | NHCf2 | NHCf | ||
VOB | VAC | VOB | VOB | AAC | VOB | VOB | VOB | |
Mixed dipterocarp | 817 | 196 | 394 | 3.7 | 1211 | 176 | 1375 | |
Peat swamp | 58 | 120 | 1.0 | 178 | ε | 178 | ||
Mangrove | 7 | 7 | ||||||
Keranga | 25 | 25 | ||||||
Total | 817 | 196 | 58 | 514 | 4.7 | 1389 | 196 | 1585 |
2.2 Plantations
A number of research investigations on plantations are currently in progress in the state. There is, however, not much likelihood of starting a large scale plantation project in the country during 1981–85.
Bibliography
(1) Department of Statistics 1970 “Population Census 1970” - Sarawak State Department - Kuching
(2) FAO 1972 “Harvesting Intensity in Selected Areas of the Hill Dipterocarp Forests at Sarawak” - FO:DP/MAL/72/009 (Working paper 22) - Rome
(3) FAO 1974 “An Inventory of the Mixed Dipterocarp Forests of Sarawak” - Volume 1 - Methodology, Techniques and Results” - FO:DP/MAL/72/009 (Technical report 2) - Rome
(4) FAO 1974 “The Mixed Dipterocarp Forests of Sarawak and Their Potential for Development” - FO: DP/MAL/72/009 (Technical report 7) - Rome
(5) State of Sarawak 1976 “Annual Report of the Forest Department” - Kuching
(6) FAO 1977 “Study to Establish Interim Guidelines for Silvicultural and Forest Management of the Mixed Dipterocarp Forest in Sarawak” - based on the work of I.D. Hutchinson - FAO draft report (MAL/75/013) - Kuching
(7) State of Sarawak 1978 “Annual Report of the Forest Department” - Kuching
(8) Chandrasekharan C. 1979 “Sarawak - Role of Forestry in Ameliorating Rural Poverty” - Preliminary mission on rural poverty study in Sarawak - FAO Regional Office - Bangkok
(9) FAO 1979 “Effect of Logging and Treatment on the Mixed Dipterocarp Forests of South East Asia” - based on the work of D.I. Nicholson (FO:MISC/79/8) - Rome
(10) State of Sarawak 1979 “Annual Report of the Forest Department” - Kuching
(11) FAO 1980 “Economic Data for Sarawak Forestry” - Draft report submitted by R.T. Fenton (MAL/76/008) - Kuching
(12) FAO 1980 “Hill Forest Silviculture for Sarawak” - Draft report based on the work of F.H. Wadsworth (MAL/76/008) - Kuching.
Nepal covers an area of 140 800 km2, between latitudes 26°20' and 30°10'N and longitudes 80°15' and 88°15'E. Almost rectangular in shape it extends over 850 km in length from east to west and 180 km in width from north to south. The country is completely landlocked surrounded by India on three sides, except north, where it borders with China. The altitude varies from less than 300 m to that of the world's highest mountain, Mount Everest, at 8 850 m. The country can be divided into three roughly parallel strips, each running east west:
the Terai is the southernmost strip about 25 km wide covering almost 17% of the total area. An extension of the Gangetic plain of northern India, it consists of generally level alluvial terrain blending into forested hills. The strip runs across the entire length of the country at the foothills with varying width except at Dang and at Chitwan where it is intercepted by the Someswar range. As a result the Terai can be conveniently divided into eastern Terai (east of Chitwan), mid - western Terai (between Chitwan and Dang-Deokhuri) and far - western Terai (west of Dang-Deokhuri). The southern parts of the Terai are densely populated and most of the area is under agriculture. The northern part of the Terai, known as the Bhabher, has a lower population density. Lying adjacent to hills its soils contain a higher proportion of boulders, gravels and sand which are washed down from the hills and mountains during monsoon rains. Most of this area is forested and is noted for its fine forests of sal (Shorea robusta) and its associates, known as Charkoshi - Jhari (“the 8 mile forests”);
the Churia range (or the Siwalik hills) corresponds to the southernmost range of mountains in Nepal. Il consists of several rugged folds, knife like ridges and steep, sharply dissected slopes. The Churia range extends east to west at an average height of 760 m and merges into the indian border through its extensions at Dang (the Dundwa range) and at Chitwan (the Someswar range). In the north it is separated from the Mahabharat range by large valleys (called duns). Some of the larger inner Terai valleyrs are those associated with the West Rapti and Babai rivers (Dang Deokhuri), Narayani and East Rapti rivers (Chitwan), Marinknola (Sindhuli - Makwanpur), Kamla (Sindhuli - Udayapur). Although the inner Terai may be considered as part of the hills the vegetation of its valleys is similar to the Terai;
the mountains cover the Mahabharat range, the areas between the Mahabharat and the Himalayas proper, the Himalayas and the inner Himalayan valleys. The Mahabharat range extends almost over the entire length of the country and most of it is below 3 300 m. The mountains therefore can be divided into the lower hills (less than 3 300 m) and the upper hills or mountains (upper Mahabharat and great Himalayas). The terrain in this region is steep and rugged.
Climatically the entire country lies in the subtropical zone but a wide range of climatic conditions exist due to altitudinal variation and topography. The Terai, being low in elevation, is hot and humid during the summer months. Temperatures around 40°C are common during May and early June before the monsoon rains start. Most of the rainfall is received from June to September. A few scattered rains occur during the winter months. Rainfall decreases from about 2 500 mm in the east to about 1 500 mm in the west. In the mountains, each hill area has its own microclimate depending on the elevation, cloud cover, steepness and direction of slope, etc.
Soils in Nepal are generally light and permeable because of the steep river gradients. The Bhabar zone consists of relatively coarse textured soils (usually with less than 20% clay), often occurring as distinct sandy and gravelly fans at the foothills of the Siwaliks. These soils are very permeable and highly susceptible to erosion and the least fertile. In the southern Terai, the soils though quite permeable are more fertile thanks to the flat terrain and a higher water table. Most of the soils in the hill valleys are also relatively coarse textured. The hill slopes have generally more clay and silt.
The microthermal climate of the lower hills is conducive to luxuriant growth of vegetation. In the upper hills, at subalpine elevations (2 700–4 000 m) winters are more severe and summers are cool. Above the tree line (4 500 m approximately) alpine tundra with shrubs and lichens prevail. The area between 4 500–8 850 m with its perpetual snow covered panorama is about 35 km wide and accounts for 15% of the total land area.
Population of Nepal according to the 1971 census amounted to 11 556 000 inhabitants (15). According to U.N. estimates the annual growth rate has been 2.3% between 1970 and 1977. The population can be estimated in 1980 at 14.2 million. The following table give its distribution by regions (5).
Actual and projected regional distribution of population (in %)
Regions | 1971 | 1976 | 1981 | 1986 | |
Eastern Region | 24.21 | 23.94 | 23.70 | 23.44 | |
Hills and mountains | 12.20 | 11.84 | 11.51 | 11.17 | |
Terai | 12.01 | 12.10 | 12.19 | 12.27 | |
Central Region | 33.45 | 33.66 | 33.88 | 34.10 | |
Hills and mountains | 18.13 | 18.09 | 18.04 | 17.99 | |
Terai | 15.32 | 15.57 | 15.84 | 16.11 | |
Western Region | 21.33 | 21.24 | 21.07 | 20.90 | |
Hills and mountains | 16.19 | 15.98 | 15.79 | 15.59 | |
Terai | 5.14 | 5.26 | 5.28 | 5.31 | |
Far Western Region | 21.01 | 21.16 | 21.35 | 21.56 | |
Hills and mountains | 15.88 | 15.68 | 15.49 | 15.30 | |
Terai | 5.13 | 5.48 | 5.86 | 6.26 | |
Subtotal hills and mountains of which Kathmandu district | 62.40 (5.00) | 61.59 | 60.83 | 60.05 | |
Sub-total Terai | 37.60 | 38.41 | 39.17 | 39.95 | |
Total country | 100.00 | 100.00 | 100.00 | 100.00 |
The 1971 population census showed that 96.16 percent of the total population lived in rural areas. Of those above 10 years age 94.37 percent formed the agricultural population. By regions, the mountains and hills had 62.40 percent and the Terai had 37.60 percent of the total population, while the distribution of cultivated land was 35.22 percent in the hills (mountains included) and 64.78 percent in the Terai. Following table shows the distribution of cultivated land and population by regions (16).
Cultivated land and population by regions (1971)
Regions | Cultivated land | Population | Households in thousand | Per capita cultivated land in ha | Per household cultivated land in ha | ||
in thousand ha | in % | in thousand | in % | ||||
Mountain | 97 | 4.86 | 1.139 | 9.86 | 205 | 0.085 | 0.473 |
Hill | 606 | 30.36 | 6.071 | 52.54 | 1,091 | 0.100 | 0.555 |
Terai | 1,293 | 64.78 | 4.346 | 37.60 | 794 | 0.297 | 1.628 |
Nepal | 1,996 | 100.00 | 11.556 | 100.00 | 2.090 | 0.173 | 0.955 |
Population in the hills grew only by 1.3 percent during 1961–71 while that of Kathmandu and of the Terai by 7.0 percent and 3.3 percent respectively. Population pressure in the hills has thus led to large scale migration into the Terai and particularly the Inner Terai. It is estimated that, from 1963 to 1972, 400 000 persons or 67 000 families have migrated to the Terai (13).
1. Present situation
1.1 Natural woody vegetation
1.1.1 Description of the vegetation types
The entire country lies within the latitudes of the subtropical region but variation in elevation, slope, rainfall, temperature and, to a large extent, soil and drainage has determined the location of major forest types. The vegetation varies from tropical moist forests to alpine scrub. The various types have been grouped under the main categories of this study.
Closed broadleaved forests (NHC)
The “sal forests” corresponding to north Indian moist deciduous forests (3 C) of Champion and Seth's classification (2) consists of forest stands where sal (Shorea robusta) is the predomimant species: 50 percent or more of the total basal area corresponds to sal. The best stands grow on moist, well drained, deep sandy loams with good subsoil drainage. On good sites sal may reach a total height up to 45 m but generally it ranges between 25 and 40 m. It is considered as a climax (climatic, edaphic or bioedaphic) formation and constitutes one of the most important forest types of Nepal, occurring in the northern Terai and valleys of the Churia hills. The type extends up to about 1 000 m in the Churia hills and in the mountains where it meets with the subtropical pine forests. Due to its resistance to fire, its coppicing power and its adaptability to various soil and site conditions it continues to retain its hold as a gregarious species despite severe biotic interference. Sal is much used in Nepal, chiefly for construction purposes. Common associates include asna (Terminalia tomentosa), jamun (Syzygium cuminii), banjhi (Anogeissus latifolia) and botdhainro (Lagerstroemia spp.). On higher reaches chir pine (Pinus roxburghii) is a common associate.
The “Terai hardwood forests” are the mixed broadleaved stands growing in the Terai which may or may not contain sal and in which other commercial timber species such as asna, jamun, botdhainro, karma or haldu (Adina cordifolia), gutel (Trewia nudiflora) and semal (Bombax ceiba) singly, on in combination, have a greater basal area than sal. They are closed forests of good height and development with a lower storey of smaller trees and a shrubby undergrowth. Several subgroups in which one species achieves dominance are represented in this type. Asna stands are among the most important subtypes and corresponds to the edaphic variant of the “moist deciduous forests” type (3/E 1) of Champion and Seth's classification (2). These broadleaved forests occur throughout the Terai and valleys of the Churia hills where soil is heavy, moisture retentive or wet and on clayey patches. Asna is used as a construction timber. Banjhi stands form another important subtype and are almost pure in the western Terai where they occupy drier sites. Although these stands are well stocked, the trees are of small size and have low commercial value at present.
The “khair - sissoo forests” corresponding to general seral types of “Tropical dry deciduous forests” (5/S2) of Champion and Seth's classification (2) occur as the first coloniser on new sandy or gravelly alluvium along large rivers in the Terai. Sissoo (Dalbergia sissoo) generally predominates. Although this type occurs throughout the Terai, it occupies significant areas only in Biratnagar, Banke, Bardia and Kanchanpur divisions. The stand canopy is light but usually fairly complete with 18 to 25 m high trees. Khair (Acacia catechu) is usually present and often inconspicuous in the mixture. It may occur sometimes in pure stands. The older forests have a more or less definite understorey composed of young trees which will replace the khair - sissoo forests as succession takes place. Tamarix dioica, Calotropis procera and Holoptelea integrifolia are often present.
The “lower slopes mixed hardwoods” occur in the eastern and central Himalayas in the moist localities between 650 m and 1 500 m. In the western Nepal the type is represented in moist hollows and depressions between 1 000 and 2 000 m elevation. These forests correspond to the type “northern montane subtropical forests” (8B/Cl) of Champion and Seth's classification (2). They are characterised by the prevalence of chestnuts (Castanopsis sp.) and chilaune (Schima wallichii) which are almost always present and also of Quercus. Shorea robusta may be found but its presence is usually ascribable to edaphic peculiarities of the sites occupied. Pines are absent or confined to drier sandy soils or well drained ridges. The forests are of good height and density, the dominant species being mostly evergreen though some large, briefly deciduous trees occur, sometimes in pure consociations such as Betula. Tree canopy reaches the height of 20–35 m under normal conditions. A middle storey of evergreen trees can generally be singled out.
The “oak forests” of Nepal are found in the Mahabharat range extending up to the subalpine region. These forests correspond to “northern montane wet temperate forests” (11 B) and “Himalayan moist temperate forests” (group 12) of Champion and Seth's classification (2). The wet forests are closed evergreen high forests of large girth but medium height, rarely exceeding 25 m. The type occurs from 1 800 to 3 000 m, mostly in the eastern Nepal where rainfall is more than 2 000 mm. Deciduous species occur, particularly at the higher altitudes but they form a relatively small proportion of the stand. Although the type is essentially a mixed one there is a marked tendency for a few species to predominate, like oaks and Lauraceae species. Quercus lamellosa, Q. pachyphylla, Castanopsis tribuloides, Acer campbellii, Machilus sp. and Michelia sp. are the most common species. The moist type consists of three common oaks providing a simple and convenient basis for subdivision into three altitudinal sones, each with its typical coniferous counterpart. Ban oak (Querous incana) occupies the lowest belt of temperate zone particularly in the outer ranges and southern aspects. The intermediate zone is occupied by moru oak (Quercus dilatata) whereas kharsoo oak (Quercus semecarpifolia) caracterizes the highest temperate belt.
The “upland mixed hardwoods” correspond to “lower and upper western himalayan temperate forests” (12/C1e and 12/C2c) of Champion and Seth's classification (2). They are deciduous forests, 20–30 m high. Trees can reach large diameters, but are usually branchy. The species occur mixed, singly or by groups of varying extent. The type is commonly found from 1 800 to 3 000 m in moist hollows and depressions often as strips along the streams and also on many of the gentler slopes. In western Nepal, typical species and genera are Aesculus indica, Juglans regia, Alnus nepalensis, Acer, Cornus, Corylus, etc.
Open broadleaved forests (NHc/NHO)
The “high savanna forests” corresponding to general seral type “Tropical moist deciduous forests” (3C/1S1) of Champion and Seth's classification (2) are commonly found in the southern parts of the Terai. Scattered trees of the early sere of the normal succession on new riverine soils, belonging almost exclusively to fire hardy species, are often of good height and stand over a very dense and tall grass layer. Among the grasses Themeda, Erianthus and Sacoharum are characteristic. Common tree species are semal (Bombax ceiba), siris (Albizia procera), gamhari (Gmelina arborea) and gutel (Trewia nudiflora).
The “alder forests” are almost pure stands, 20 to 30 m high, occuring as strips of varying width, interspersed by cultivation along stream sides. The type corresponds to seral type “himalayan moist temperate forests” (12/1sl) of Champion and Seth's classification (2). An understorey may or may not be present. Alnus nepalensis and Trema orientalis are characteristic species.
The “birch/fir forests” corresponding to “sub-alpine forests” (14/C1, 14/C2) of Champion and Seth's classification (2) occur above 3 000 m. The type is represented by small crooked trees or large shrubs with patches of dominant coniferous trees (generally Abies, sometimes Pinus wallichiana) low, branchy and densely leaved. Birch (Betula utilis) is the only typical broadleaved tree to develop a fairly clean bole, all the others having crooked and branchy stems. The conifers rarely reach 30 m height except in sheltered spots and the broadleaved are usually 6 to 10 m high. Besides birch and fir, many species of Rhododendron are quite often present.
Coniferous forests (NS)
The coniferous forests of Nepal may be conveniently divided into lower level forests, primarily of chir pine (Pinus roxburghii) and high level ones of blue pine (Pinus wallichiana), fir (Abies pindrow), spruce (Picea smithiama) and hemlock (Tsuga sp.).
The “chir pine forests” correspond to “subtropical pine forests” (group 9) of Champion and Seth's classification (2). This type occurs mainly on the Churia hills and on the lower slopes of the Mahabharat range between 1 000 and 1 800 m, extending from ridges down to 600 m and up to 2 300 m on southern exposure. At the lower altitudes it occurs mixed with sal (Shorea robusta), whereas at the upper limits ban oak (Quercus incana) is found intimately mixed. The type consists practically of a pure association of chir pine with almost no understorey. Shrubs even are few on the slopes of the Mahabharat range. The top canopy is usually 20 to 35 m high but is rarely complete. These forests occur on a wide range of climatic conditions with rainfall from 900 mm to more than 2 000 mm but are generally confined to western Nepal. In the central and eastern parts of the country they are present only on dry sites. On the Churia hills chir pine occurs in pure stands or in mixture with scattered deciduous trees in the lower storey. The deciduous species besides sal are Terminalia tomentosa, Anogeissus latifolia, Syzygium cumini, Cedrela toona, etc. Chir forests are rarely found on flat terrain as only a few such places have escaped clearing for cultivation. Above 2 000 m the vegetation becomes in general completely temperate and chir pine is replaced by blue pine (Pinus wallichiana) although it may go up to 2 400 m at places.
In moist temperate climatic conditions coniferous stands are the majority and correspond to “himalayan moist temperate forests” (group 12) of Champion and Seth's classification (2). These forests on the southern side of the Himalayas occur at an elevation of over 2 450 m and are composed of fir (Abies pindrow), hemlock (Tsuga dumosa), spruce (Picea smithiana), cypress (Cupressus torulosa), blue pine (Pinus wallichiana) and deodar (Cedrus deodara). They are generally inacessible at present. They are now an important source of timber and fuelwood to villagers living in the mountain valleys. They are also important in protecting the upper parts of mountain watersheds. Often they are overmature.
Scrub formations (nH)
The typical scrub formations in Nepal are those corresponding to groups 10, 15 and 16 of Champion and Seth's classification (2) viz. “subtropical evergreen”, “moist and dry alpine scrub”. Besides these typical formations, there are various degradation stages of climax high forests, resulting from excessive biotic interference. Such formations are limited in extent and occur only on areas with difficult climatic and edaphic conditions.
“Subtropical evergreen scrub” is represented by a low scrub forest of small broadleaved evergreen trees and shrubs including thorny species. These stands are distributed on the Bhabar tract, the Churia hills and the foothills of the western Mahabharat range. Typical species are Acacia modesta and Olea cuspidata along with Dodonea viscosa, Carissa spp. and Euphorbia spp..
“Alpine scrub” correspond to a low, almost evergreen, forest of Rhododendron mixed with some birch and other deciduous species. Trunks are short and branchy. The type occurs near 4 000 m, extending gradually to lower altitude westwards. The main characteristic is an ample snowfall, the snow lying till the air day temperature is quite warm. A thick layer of black humus is present and the soil is generally wet. Besides Rhododendron and birch, Juniperus recurva is commonly found.
1.1.2 Present situation of the woody vegetation
Present areas
The present extent and distribution of the forest cover is not known with certainty. Large discrepancies exist between the various sources of information. The only available comprehensive set of forest resources dates back to 1964 and has been used as a base to arrive at estimates for 19801. The Forest Resources Survey Office of the Forest Department, in cooperation with USAID, carried out a country-wide inventory between 1963 and 1965 with the help of vertical aerial photographs taken during the same period and published the forest resources statistics for the Terai, Siwalik and southern Mahabharat (1) for the Timber Corporation of Nepal forest reserve, for the Bheri-Karnali region and for the hills (4). Forest area estimates for the gaps of the photographic and map coverages have been made on the basis of the report of the region to which they belong. The results are tabulated hereunder (14).
Forest areas at end 1964
(in thousand ha)
Region | Commercial | Non-commercial | Total forest | Non-forest | Total land area |
Terai, Siwalik and southern Mahabharat range | 1239 | 412 | 1651 | 1488 | 3139 |
Timber Corp. of Nepal area | 116 | 56 | 172 | 62 | 234 |
Bheri-Karnali region | 128 | 105 | 233 | 43 | 276 |
Hills | 1226 | 2338 | 3564 | 2576 | 6140 |
Unsurveyed gaps (estimates) | 276 | 506 | 782 | 558 | 1340 |
Northern border area | 2951 | 2951 | |||
Total | 2985 | 3417 | 6402 | 7678 | 14080 |
Percent of total area | 21.20 | 24.27 | 45.47 | 54.53 | 100.00 |
The present forest areas have been derived from the estimates above assuming annual forest losses of 5.0 percent in the Terai and 1.5 percent in the Hills (see section 2.1.1)-Further division into various categories has been made on the basis of the indications found in documents (6) (13) and in an unpublished study of the Indian Preinvestment Survey of Forest Resources (PIS). The results are given in the following table.
Areas of natural woody vegetation estimated at end 1980
(in thousand ha)
Category | NHCf1uv | NHCf1uc | NHCf1 | NHCf2i | NHCf2r | NHCf2 | NHCf | NHCa | NHc/NHC(2i) | nH |
Sal | 335 | 150 | 485 | 200 | 60 | 260 | 745 | 60 | 60 | |
TBL 1 | 165 | 75 | 240 | 40 | 90 | 130 | 370 | 40 | 90 | 120 |
KS 1 | 25 | 25 | 15 | 15 | 40 | 10 | 20 | |||
Others | 240 | 65 | 305 | 30 | 120 | 150 | 455 | 30 | 90 | |
Subtotal broadleaved | 740 | 315 | 1055 | 285 | 270 | 555 | 1610 | 110 | 180 | 230 |
NHBf1uv | NHBf1uc | NHBf1 | NHBf2i | NHBf2r | NHBf2 | NHBf | NHBa | |||
Bamboo | 1 | 1 | 1 | ε | ||||||
NSf1uv | NSf1uc | NSf1 | NSf2i | NSf2r | NSf2 | NSf | NSa | |||
Coniferous | 145 | 70 | 215 | 55 | 60 | 115 | 330 | ε | ||
N.f1uv | N.f1uc | N.f1 | N.f2i | N.f2r | N.f2 | N.f | N.a | |||
Total | 885 | 385 | 1270 | 341 | 330 | 671 | 1941 | 110 |
1 “Terai hardwood forests”
2 “Khair-sissoo forests”
N.f1uv represents unmanaged virgin productive forest areas on which little population pressure is exerted; timber and fuelwood are removed only by villagers and nomads and this does not appreciably affect the facies of these forests;
N.f1uc corresponds to forests that are subjected to heavy population pressure and in the absence of scientific management have been gradually transformed into logged over forests;
N.f2i stands for forests unproductive for physical reasons only. Those forests which are unproductive for physical reasons but have been covered by some legislation or management plan where commercial production has not been prescribed have been grouped under N.f2r forests unproductive for legal reasons, i.e. for wildlife, aesthetic or other reasons, where commercial exploitation is prohibited.
Ownership
All the forests of the country are owned by His Majesty's Government of Nepal and the Department of Forests under Ministry of Forests looks after the various forestry activities. Present extent of private, “panchayat” and “temple” forests is very small, but plans exist for the extension of private and community (panchayat) forests.
Legal status and management
It is only recently that a national forest policy was declared and most of the forests have not been properly demarcated. In an effort to rationalize forest management, the Department of Forests has classified the forests into the following six groups:
(i) “protection forests” are those forest areas to be maintained or possibly rehabilitated, mainly for erosion and flood control, and those areas earmarked for special treatment under watershed management. These forests are generally located on steep slopes and are poorly stocked;
(ii) “production forests” are located on relatively flat lands with low agricultural potential (mainly permeable Bhabar soils), where intensive forestry is possible with little risk of soil erosion. It should be noted however that the term “production forest” does not imply that the forest has a regeneration rate sufficient to sustain a commercially appreciable yield without capital depletion. Wood production is at present largely a mining operation;
(iii) “special forests” are set aside as wildlife reserves, national parks, etc. Special forests are included in the four national parks which cover a total area of 399 000 ha and in three wildlife reserves and sanctuaries with a total area of 59 000 ha;
(iv) “limited use forests” consist of scattered patches which can provide limited produce to the local communities;
(v) “alienable forests” may be transferred to agriculture, if required;
(vi) “border fellings” correspond to those areas to be clearfelled and settled, mainly along the Indian border.
The area distribution of these classes in the Terai is given in the following table (12).
Forest area in Terai and its functional classification based on the 1974 land use survey (in thousand ha)
Protection forests | 757 | |
encroached | (15) | |
not encroached | (742) | |
Production forests | 355 | |
encroached | (9) | |
not encroached | (346) | |
Special forests | 75 | |
Limited use forests | 93 | |
encroached | (10) | |
not encroached | (75) | |
Alienable forests | 93 | |
encroached | (18) | |
not encroached | (83) | |
Border fellings | 31 | |
All forests | 1404 | |
encroached | (52) | |
not encroached | (1352) |
Scientific forest management has not a long past. Because of their accessibility and the easy working conditions, the Terai forests have been given more attention in the field of management, and working plans and management plans have been prepared for some of these forests. The working of forests for timber exploitation, whenever carried out in a systematic way, follows the lines of either single tree selection or clearfelling systems. Timber stand improvement works like climber cutting, removal of dead, dying and moribund trees, are included in the regular schedule of the development works of the Department of Forests. However the traditional “selection system”, and the provisions of the new management plans are not presently operational. To mitigate the damage to forests by fires, construction of firebreaks is also carried out in the Terai forests.
Forest utilization
Log harvesting
The government has experimented various methods of sales. Initially, long-term concessions were negotiated with private entrepreneurs. The system was however opened to abuse and gave rise to frequent litigation. It was therefore replaced by two different systems - auction and quota. With the first, blocks of forest were auctioned to the highest bidder who was not usually a sawmiller; quotas were allocated to sawmillers on payment of the appropriate royalty only for the supply of their own mill. Both these systems were dropped in 1969 and replaced by the so-called “evaluation method”. A monetary value was put on the timber and anyone could apply for purchase of cutting rights. Naturally there were more applications for accessible and well stocked forests. In 1974 the government reverted to the auction system without the quota system this time.
Generally trees are felled and logs are bucked with axe and saw. Hauling from the forest is done by bullock carts and trucks. The Timber Corporation of Nepal is the first government agency engaged in logging operations and uses modern equipment. Recently, the Department of Forests itself has entered the scene through the Forest Products Development and Sale Board.
There is practically no industrial use of wood in the Hill region, and logging and wood industries are restricted to the Terai. Sawmilling is the most popular wood-based industry in the country. Private sawmills are spread over most of the Terai districts, mainly Biratnagar, Birganj and Kanchanpur. There are two plywood mills, one privately owned at Biratnagar with a capacity of about 5 000 m3 wood intake per year and another, partly state owned, at Botwal with some 7 000 m3 wood intake capacity. Since the early sixties, sawlogs have been, and still are the main forest products exported (to India essentially). Recorded annual production of sawlogs and veneer logs reached its maximum (340 000 m3) in 1973/74. Recently however the government has been curbing timber sales in an effort to discourage export of logs to India, and as a consequence the recorded log outturn dropped to about 170 000 m3 in 1975/76 (10).
Main species harvested from the Terai forests are sal (Shorea robusta), asna (Terminalia tomentosa) shisham (Dalbergia sissoo), semal (Bombax ceiba), haldu (Adina cordifolia). Distribution of these species in the total harvest is not available.