2.1.4 Areas and growing stock by end 1985
Keeping in view the likely effect of various factors changing the state of forest described earlier, area and volume expectations for 1985 are the following:
Areas of natural woody vegetation estimated at end 1985
(in thousand ha)
Category | NHCf1uv | NHCf1uc | NHCf1 | NHCf2i | NHCf2r | NHCf2 | NHCf | NHCa | |
Broadleaved | Mixed dipterocarp | 2 600 | 3 650 | 6 250 | 1 510 | 690 | 2 200 | 8 450 | 2 400 |
Mangrove | 115 | 115 | 115 | 120 | |||||
Mossy | 300 | 300 | 300 | ||||||
Total broadleaved | 2 600 | 3 650 | 6 250 | 1 925 | 690 | 2 615 | 8 865 | 2 520 | |
NSf1uv | NSf1uc | NSf1 | NSf2i | NSf2r | NSf2 | NSf | NSa | ||
Coniferous | 185 | 185 | 185 | ε | |||||
N.f1uv | N.f1uc | N.f1 | N.f2i | N.f2r | N.f2 | N.f | N.a | ||
Broadleaved and coniferous | 2 600 | 3 835 | 6 435 | 1 925 | 690 | 2 615 | 9 050 | 2 520 |
Growing stock estimated by end 1985
(in million m3)
Category | NHCf1uv | NHCf1uc | NHCf1 | NHCf2 | NHCf | ||
VOB | VAC | VOB | VOB | VOB | VOB | ||
Broadleaved | Mixed dipterocarps | 795 | 235 | 600 | 1 395 | 185 | 1 580 |
Mangrove | 9 | 9 | |||||
Mossy | 15 | 15 | |||||
Total broadleaved | 795 | 235 | 600 | 1 395 | 209 | 1 604 | |
NSf1uv | NSf1uc | NSf1 | NSf2 | NSf | |||
VOB | VAC | VOB | VOB | VOB | VOB | ||
Coniferous | 17 | 17 | 17 | ||||
N.f1uv | N.f1uc | N.f1 | N.f2 | N.f | |||
VOB | VAC | VOB | VOB | VOB | VOB | ||
Broadleaved and coniferous | 795 | 235 | 617 | 1 412 | 209 | 1 621 |
2.2 Plantations
The situation in respect of the industrial plantations is expected to improve in view of a recent government policy decision to allocate forest land for the purposes of industrial plantations. Initially some 1.7 million ha of land have been earmarked for development into industrial plantations, tree farms and agro-forestry projects. With the help of credit facilities recently offered by the Development Bank of the Philippines, Communal Tree Farm Projects are expected to gain momentum. Involvement of the community and of the citizen in the afforestation is also expected to increase considerably as compared to past through the drive under the Programme for Ecosystem Management.
On account of ease of propagation and associated economic return Albizia falcataria, Gmelina arborea, Leucaena leucocephala, Eucalyptus deglupta would continue to be the preferred broadleaved species and Pinus caribaea the main coniferous one.
Projections for the industrial and other plantations are given in the following two tables: the third table presents the overall summary.
Areas of established industrial plantations estimated at end 1985 1
(in thousand ha)
Category | Species | Years | 81–85 | 76–80 | 71–75 | 66–70 | 56–65 | 46–55 | before 46 | Total |
Age class | 0–5 | 5–10 | 11–15 | 16–20 | 21–30 | 31–40 | >40 | |||
PH.1=PHH.1 | Albizia falcataria Eucalyptus deglupta Gmelina arborea Leucaena leucocephala | 45 | 38 (50) | 6 (12) | 6 (12) | 7 (14) | 1 (ε) | 103 (135) | ||
PS.1 | Pinus caribaea (mainly) | 5 | 5 (6) | 2 (4) | 12 (15) | |||||
P..1 | Total industrial plantations | 50 | 43 (56) | 8 (16) | 6 (12) | 7 (14) | 1 (2) | 115 (150) |
1 Distribution by age classes until 1975 is only tentative.
Areas of established non-industrial plantations estimated at end 1985 1
(in thousand ha)
Category | Species | Years | 81–85 | 76–80 | 71–75 | 66–70 | 56–65 | 46–55 | before 46 | Total |
Age class | 0–5 | 5–10 | 11–15 | 16–20 | 21–30 | 31–40 | > 40 | |||
PHL 2 | Hardwood species other than fast-growing ones | 75 | 63 (82) | 5 (14) | 5 (15) | 14 (48) | 2 (6) | ε (ε) | 164 (233) | |
PHH 2 | Fast-growing hardwood species | 75 | 63 (82) | 4 (14) | 5 (14) | 13 (41) | 2 (6) | ε (ε) | 162 (232) | |
PH.2 | Subtotal hardwood species | 150 | 126 (164) | 9 (28) | 10 (29) | 27 (82) | 4 (12) | ε (ε) | 326 (465) | |
PS.2 | Softwood species | 50 | 42 (54) | 3 (9) | 3 (10) | 10 (29) | 1 (3) | ε (ε) | 109 (155) | |
P..2 | Total non-industrial plantations | 200 (218) | 168 (37) | 12 | (111) | 37 | 5 (ε) | ε | 435 (620) |
Areas of established plantations estimated at end 1985 1
(in thousand ha)
Category | Species | Years | 81–85 | 76–80 | 71–75 | 66–70 | 56–65 | 46–55 | before 46 | Total |
Age class | 0–5 | 5–10 | 11–15 | 16–20 | 21–30 | 31–40 | > 40 | |||
PHL | Hardwood species other than fast-growing ones | 75 | 63 (82) | 5 (14) | 5 (15) | 14 (41) | 2 (6) | ε (ε) | 164 (233) | |
PHH | Fast-growing hardwood species | 120 | 101 (132) | 10 (26) | 11 (26) | 20 (55) | 3 (8) | ε (ε) | 265 (367) | |
PH | Subtotal hardwood species | 195 | 164 (214) | 15 (40) | 16 (41) | 34 (96) | 5 (14) | ε (ε) | 429 (600) | |
PS | Softwood species | 55 | 47 (60) | 5 (13) | 3 (10) | 10 (29) | 1 (3) | ε (ε) | 121 (170) | |
P | Total all plantations | 250 | 211 (274) | (53) | 19 (51) | 44 (125) | 6 (17) | ε (ε) | 550 (770) |
1 See footnotes of two preceding tables
Bibliography
(1) Whitford, H.N. 1911 “The Forests of the Philippines” - Bureau of Forestry bulletin No. 10 - Manila
(2) Bureau of Forest Development 1970 “Philippines Forestry Statistics 70” - Manila
(3) FAO 1970 “Forestry Economics” - FO: SF/PHI 16 - Technical Report 1 - Rome
(4) FAO 1970 “Reforestation” - based on the work of T.J. Wormald - FO: SF/PHI 16 - Technical Report 2 - Rome
(5) FAO 1971 “Shifting cultivation” - based on the work of E. Ozbilen - FO: SF/PHI 16 - Technical Report 9 - Rome
(6) FAO 1974 “Philippines” - Adviser's Assignment Report No. 3 - UNDP/FAO RAS/72/125 Project - Regional Tropical Forest Management Adviser - Bangkok
(7) FAO 1975 “Prefeasibility Study for Wood-Based Panel Industries in the Philippines” - prepared by Jaako Pöyry and Co - Project UNDP/FAO RAS/74/007 - Philippine Report - Helsinki
(8) FAO/World Bank Cooperative Programme 1975 “Report of the Philippines Forestry Pulpwood Plantation Project (Identification)” - Report No. 6/75 - PHI 9 - Rome
(9) Bureau of Forest Development 1977 “National Progress Report in Forestry (Period: 1974–1976) Republic of the Philippines” - prepared for the 10th session of the Asia Pacific Forestry Commission (Kathmandu, Nepal, 6–10 June 1977) - Manila
(10) FAO 1977 “Derivation of a Commercial Plantation Programme for the Philippines to the Year 2000 from Wood Supply/Demand Projections” - by N.D. Endacott - PHI/72/006 - Project Working Paper No. 10 - Manila
(11) FAO 1978 “Identification and Planning of a National Forest Inventory for the Philippines” - by N.E. Nilson, H. Marsch, K.D. Singh - PHI/72/006 - Project Working Paper No. 15 - Manila
(12) Lachowski, H.M. et al. 1978 “landsat Assisted Forest Inventory of the Philippines Islands” - Natural Resources Management Center - Research Monograph No. 4, series of 1978 - Manila
(13) National Economic and Development Authority 1978 “Philippine Statistical Yearbook” - Manila
(14) Tagudar, E.T. 1978 “Forest Surveys and Forestry Planning for a Fully Integrated Wood Processing Complex in the Philippines : PICOP's Experience and Viewpoint” - in Report on the FAO/SIDA/GOI Seminar on Forestry Resources Appraisal in Forestry and Land-Use Planning - FAO/SWE/TF - RAS 62 - Rome
(15) Virtucio, F.D. and Dalangin, N.B. 1978 “Nationwide Forest Inventory: the Philippine Experience” - in Report on IUFRO Meeting on National Forest Inventory (18–26 June 1978) - Bucharest
(16) Agriculture Department 1979 “Philippines Agricultural Statistics” - Manila
(17) Bureau of Forest Development 1979 “1978 Philippine Forestry Statistics” - Manila
(18) FAO 1979 “The Effects of Logging and Treatment on the Mixed Dipterocarp Forests of South East Asia” - by D.I. Nicholson - FO: MISC/79/8 - Rome
(19) FAO 1979 “Management Research of Philippine Dipterocarp Forest” - by J. Wyatt - Smith-FO: DP/PHI/72/006 - Working Paper No. 14 - Rome
(20) Forest Research Institute 1979 “Looking back… 1979 Gains” - in Evergreen - Vol. V No. 1 - Los Baños (Philippines)
(21) Bureau of Forest Development 1980 “Country Report on Forestry of the Republic of the Philippines” - UNCTAD Meeting on Transnational Corporations - Manila
(22) Bureau of Forest Development Letter of 24/3/81 of Director, Bureau of Forest Development to Assistant Director General, Forestry Department, FAO on FAO/UNEP Tropical Forest Resources Assessment Project - Manila
Sri Lanka covers an area of 65 584 km2 (including 960 km2 of inland water) between latitudes 5°55' and 9°55' N and longitudes 79°41' and 81°54' E. The coastline is about 1 600 km broken by extensive salt water lagoons and bays. Administratively it is divided into 9 provinces which are further divided into 24 districts. It is constituted of two main physiographic zones:
the highlands lie in the central and southwestern parts of the island rising to elevations higher than 2 000 m. All the rivers of the country originate in this part and radiate towards the coast. Basically it consists of a high core flanked on all sides by lower valleys and plateaux. The main physiographic subdivisions within the highlands are the high plains and the ridges radiating from the Pidurutalagala peak, the Knuckles ranges, the Uva basin, the Horton plateau, the Lunugala ridges and the Sabaragamuwa ridges;
the western lowland plains cover the entire northern half of the country; in their eastern and southeastern parts and in the southwest they are reduced to a narrow strip between the highlands and the coast. Their surface is level to undulating.
Climate is tropical and maritime. Most of the rainfall is received in the highlands through southwest monsoon during summer (from June through September). The northeast monsoon brings a fair amount of rainfall to the plains and a heavy rainfall to the eastern part of the central highlands. Two other rainy periods at spring (March to May) and fall (September to November) are of significance. Sri Lanka can be divided roughly into a northern dry zone and a southern wet zone merging into an intermediate zone in between. The dry zone occupies almost two thirds of the land and consists mainly of flat and undulating land where the major irrigation schemes are in operation and the bulk of the agricultural and forestry activities take place. Annual rainfall varies from 750 mm to 1 850 mm. The wet zone has an annual rainfall ranging from 2 500 mm to 5 000 mm. It occupies the southwestern regions and consists of a narrow coastal plain and very rugged mountainous areas culminating at 2 750 m. Rainfall is abundant throughout the year. The mean monthly temperature varies from 30°C in the lowlands to 20°C in the highlands above 2 600 m.
The soils belong to two categories: one derived from the parent material and their erosion products and those derived from transported materials. The former are generally clayey soils whereas the latter ones are light sandy loams.
Present population can be estimated at 14.9 million inhabitants and grows at an annual rate of 1.8 percent (FAO Production Yearbook, Vol. 33). This corresponds to a very high overall density of some 230 inhabitants per km2. Agriculture plays a key role in the country's economy and is the main source of employment (agricultural population: 7.9 million people). It contributes about 31 percent to GDP and accounts for 75 percent of foreign exchange earnings. Forestry's contribution to GDP is estimated to be in the region of 2%. However this estimate does not take into account most of fuelwood production which is not commercialized, but constitutes the most important source of domestic energy.
1. Present situation
1.1 Natural woody vegetation
1.1.1 Description of the vegetation types
More than 150 indigenous timber species are present in the natural forests of Sri Lanka. Most of them are confined to the wet zone while the forests of the dry zone and of the drier parts of mountain zone contain fewer valuable species and have a lower stocking. The natural vegetation has been classified by de Rosayro (1) into dry mixed evergreen, wet and montane evergreen, intermediate evergreen forest, montane grassland, savanna and mangrove. Another classification by Andrews (2) distinguishes seven major forest groups, viz. tropical thorn, tropical dry mixed evergreen, tropical lowland semi-evergreen, lowland wet evergreen, highland wet evergreen, tropical montane forest and grassland. The following description is derived partly from document (1) and presented within the broad categories used in this study.
Closed broadleaved forests (NHC)
The “montane wet evergreen” forests occupy the mountain zone from 1 500 m and upwards. They are closed forests, the trees being mostly short boled and branchy though often attaining very large diameters. The height of the canopy is relatively low and exceeds rarely 20 m. Generally they occur in patches in the more sheltered sites on rolling grounds. The temperature averages about 16°C and rainfall about 2 000 mm. Distinction between this type and the tropical and subtropical forests at lower elevation is generally not well marked. Main species are Syzygium spp., Elaeocarpus glandulifera, Michelia nilagirica, Gordonia spp., Calophyllum walkeri, Meliosma simplicifolia, Ternstroemia japonica, Litsea spp., etc.
Montane semi-evergreen forests occur between 900 and 1 500 m altitude with average. temperatures ranging from 15°C to 20°C and more than 1 500 mm of annual rainfall. They are closed forests of medium height (18 to 24 m) sometimes reaching 30 m on favourable sites. Main species are Doona congestiflora, D. trapezifolia, Palaquium spp., Homalium zeylanicum, Calophyllum calaba, C. tomentosum, C. pulcherrimum, Syzygium spp., Kurrimia zeylanica, etc.
The “lowland wet evergreen forests” occupy the southwestern part of the country from the coastal plains up to 900 m. The climate is characterised by an annual rainfall exceeding 2 000 mm and an average temperature above 20°C they are closed high forests with a generally dense canopy 22 to 27 m high; dominant trees may attain heights between 30 and 45 m. Certain species tend to predominate though the forests are mostly heterogeneous. They are generally free from human interference. Typical species are Dipterocarpus zeylanicus, D. hispidus, Doona spp., Pygeum zeylanicum, Vatia spp., Hopea spp., Shorea spp., Palaquium spp., Xylopia parvifolia, Canarium zeylanicum, Vitex pinnata, etc.
The “tropical moist deciduous” forests occupy the plains north, east and south of the central highlands extending on the hills slopes to an elevation of 600 m. The climate is characterised by an annual rainfall between 1 400 and 2 000 mm with a dry period of 3 to 6 months. Average temperature is usually more than 6°C. The canopy is usually 18 to 20 m high with dominant trees up to 25 m and is formed by deciduous and semi-deciduous species such as Chloroxylon swietenia, Adina cordifolia, Berrya cordifolia, Vitex pinnata, Pterospermum canescens, Holoptelea integrifolia, Sterculia foetida, Schleichera oleosa, Albizia odoratissima, Grewia polygama, etc. The understorey is usually composed of semi-evergreen species such as Garcinia spicata, Pleurostylia opposita, Syzygium cumini, Sapindus emarginatus, Cassia fistula etc.
The mangroves constitute a relatively minor type forming a thin belt around lagoons and river mouths. They cover about 3 200 to 4 000 ha according to Seneviratne quoted by Christensen in “Mangrove Forest Resources and their Management in Asia and the Far East”. In the past, mangroves occupied much larger areas but extensive areas have been reclaimed for coconut plantations (according to Abeywickerama quoted by Christensen). They are characterised by typical mangrove species such as Rhizophora spp., Avicennia officinalis, Bruguiera cylindrica, Sonneratia sp., Excoecaria agallocha etc.
Open broadleaved forests (NHc/NHO)
Savannas are found to the east of the mountain zone between 500 and 1 700 m altitude. They are characterized by a dense layer of tussock grasses such as Cymbopogon confertiflorus and Imperata cylindrica. Principal tree species are Careya coccinea, Terminalia bellerica, T. chebula, Emblica officinalis, Pterocarpus marsupium, Albizia odoratissima, Diospyros melanoxylon, Butea frondosa and Anogeissus latifolia. Their total extent is relatively small.
Scrub formations (nH)
Tropical thorn forests occuring on plains from northwest to southeast, generally below 300 m elevation, may be classified as scrub formations. They occupy areas having less than 1 000 mm rainfall with 5 to 7 dry months. The average temperature is always more than 20° C. They are open low forests in which thorny species predominate. Trees usually have short boles and low branching crowns which rarely join. Height is usually 6 to 9 metres. In the mixture of species, the most common ones are: Acacia leucophloea, A. chundra, Carissa spinarum, Dichrostachys cinerea, Randia dumetorum, Euphorbia antiquorum, Ziziphus spp., etc.
1.1.2 Present situation of the woody vegetation
Present areas
The last comprehensive inventory of Sri Lanka forest resources was carried out in 1959–60 based on 1956 aerial photography. Total forest area was estimated at that time at 2.9 million hectares. During the last two decades widespread deforestation has occurred. Estimates of present areas vary according to the documents. The total forest area of 1970 is given as 2.4 million ha in document (4). (6) gives a total forest area of 1 682 000 ha at the end of 1973 excluding national parks and nature reserves, man-made forests and “unstocked” forests. On the basis of documents (5), (7) and (9) and taking into account the area occupied by shifting cultivation and the average annual rate of excision of forests during the last years (see section 2.1.1), the present total forest area is estimated at 1 659 000 ha, excluding forest fallows.
The changes in area by ecological zones during the period 1960–70 have been derived from documents (2) and (4) and projected to 1973. The excision figures by forest divisions mentioned in documents (5), (7) and (9) have been used to estimate changes in forest area from 1973 to 1980.
On the basis of the above indications the estimates presented in the table below have been arrived at.
Areas of natural woody vegetation estimated at end 1980
(in thousand ha)
NHCf1uv | NHCf1uc | NHCf1 | NHCf2i | NHCf2r | NHCf2 | NHCf | NHCa | NHc/NHO | nH |
17 | 1213 | 1226 | 240 | 193 | 433 | 1659 | 853 | ε | 215 |
Some explanations are necessary for a proper interpretation of the above table:
the forests situated mainly in the mountainous region which have not been commercially exploited, mainly because of the difficult terrain, are classified as unmanaged virgin closed broadleaved forests (NHCf1uv). There is some biotic interference but its effects is not significant;
the forests which are under exploitation without any management regulations and in which up to half of the growing stock has been removed are classified as unmanaged logged closed broadleaved forests (NHCf1uc);
none of the forests are considered intensively managed in the meaning used in this study (NHCf1m=0);
forests which are not considered suitable for commercial exploitation either for topographic reasons and/or for poor stocking are considered unproductive for physical reasons (NHCf2i);
forests which have been constituted into national parks, natural reserves or Man and Biosphere reserves where commercial exploitation is prohibited by law are classified as forests unproductive for legal reasons (NHCf2r);
secondary regrowth on land abondoned by shifting cultivation is classified as forest fallow (NHCa);
there are patches of wooded savanna in the mountainous wet zone as well as in the northern dry zone (1). Their exact area is not available but is relatively small;
an important area of scrub vegetation with some large scattered trees is included in forests unproductive for physical reasons (NHCf2i).
Ownership
Almost all the forests are state owned. The Land Reform Acts of 1973 and 1975 introduced a change in land ownership by affecting all private lands over 20 hectares to the government. The state owned forests are administered in the following manner:
forest reserves (natural forests and plantations) and other state forests over 200 ha (500 acres) in the dry zone and 20 ha (50 acres) in the wet zone are under the direct control of the Forest Department, Ministry of Lands and Land Development;
wildlife reserves and sanctuaries are under the control of Wildlife Conservation Department, Ministry of State;
other state forests less than 200 ha (500 acres) in the dry zone and 20 ha (50 acres) in the wet zone are under the administration of the governments agents of the respective districts under the technical guidance of the Conservator of Forests.
Legal status and management
The forests are classified into the following legal classes:
proclaimed reserves include those forests which have been notified as such after proper demarcation, restricting the accessibility and rights of the local population;
proposed reserves are those forest areas where the process of notification is in progress;
other state forests include all other forest land, whether vegetated or not, with the exception of forest plantations and of the following other categories:
strict natural reserves are notified forest areas where fauna and flora are left completely undisturbed; admission is prohibited except for research;
national parks are those forest areas which have been notified to preserve one or several ecosystems; forest exploitation is prohibited;
sanctuaries are the forest areas where killing of wildlife is totally prohibited;
intermediate zones and jungle corridors, are those areas where shooting of wildlife is prohibited in a particular season.
There are no formal forest working plans for individual forest areas and consequently no forest area has been classified as intensively managed forest (NHC1m=NHc/NHO1m=0). The plan is for the whole of Sri Lanka with specific project working circles. The forests in the dry zone are clearfelled and often reforested by seedlings. In the wet zone the main silviculture practice is selective felling. All utilizable species over 1.5 m girth at breast height (48 cm DBH) are felled. Other cultural operations, such as removal of non-commercial species, are not carried out due to lack of staff. In some restricted areas of the wet zone, where hora (Dipterocarpus zeylanicus) is found in abundance, shelterwood fellings are carried out for the regeneration of this species. A widely practised method for the enrichment of the poorly stocked forests of the wet and intermediate zones consists in the underplanting of Swietenia macrophylla. At high elevations poorly stocked grasslands are planted with Pinus caribaea and Pinus patula (see section 1.2).
Forest utilisation
Log harvesting
All logging operations are carried out by the STC (State Timber Corporation under the Ministry of Lands and Land Development) and the Plywood Corporation (under the Ministry of Industries and Ministry of Scientific Affairs). The Plywood Corporation extracts an annual volume of 20 to 22 000 m3 of hardwood sawlogs and peeler logs from the 10 500 ha forest block allotted to them. The rest of the logging is done by STC. A major part of the outturn comes from the dry zone, where extensive clearcutting is carried out in addition to selective felling practised in the reserves and proposed reserves. Much of the former consists in salvage operations on land that has to be released for other uses, chiefly agriculture. The balance consists of areas earmarked fro teak plantations. STC carries out directly mechanical logging or entrusts the work to contractors (on the basis of tenders) who extract wood using elephants or bullock carts. Mechanical logging is done only in the wet zone. Experience has shown that the rugged terrain of the wet zone forests is more suited to semi-mechanised harvesting using elephants instead of skidding tractors. Timber extracted is sold through STC depots to private consumers and to private and STC processing industries at fixed prices.
Other forest products
Estimates of household fuelwood requirements vary between 3.8 to 6.9 million m3 per year (13) while industrial requirements are calculated at 0.7 million m3. Indications on the exact level of fuelwood production/consumption have not been found. The recorded fuelwood production from the forests is given at 0.14 million m3 only (11). Fuelwood supply to tea estates is made through a fuel coupe system. Each estate is allocated 0.8 to 2.0 ha of natural forest area per year (mainly in the montane wet evergreen forests called “sholas”) with the stipulation that the estate will replant the area with Eucalyptus grandis immediately after felling. Rotation is 10 to 12 years and estates are allocated 10 to 12 blocks for their use on stumpage value. At present about 100 fuel coupes are in operation. No more “sholas” will be allocated in the future for fuelwood coupes and estates are asked to plant waste land available in their area. For meeting the household energy requirements fuelwood is obtained as a by-product of logging operations and from industrial wastes. A substantial quantity is obtained from illicit cutting of trees (11). Wood fuels are also extracted from rubber plantations, gardens and orchards and from agriculture wastes.
1.1.3 Present situation of the growing stock
The average growing stock of the productive forests of the wet, intermediate and dry zones has been estimated in the 1959–60 nationwide forest inventory at 124, 58 and 52 m3/ha respectively and that of the unproductive forests of the three zones at 43, 36 and 22 m3/ha. Since then there has been no inventory to update these figures. It has been assumed tentatively that, on an average, these growing stock figures have to be reduced by 15 percent to account for degradation due to heavy population pressure during the last twenty years.
The present situation of the growing stock is summarized in the following table:
Growing stock estimated at end 1980
(totals in million m3)
NHCf1uv | NHCf1uc | NHCf2 | |||||
VOB | VAC | VOB | VOB | ||||
m3/ha | total | m3/ha | total | m3/ha | total | m3/ha | total |
200 | 2.6 | 60 | 0.8 | 60 | 73 | 20 | 9 |
The mean annual increment has been estimated at 1.1 to 6.6 m3/ha for all species in the wet zone and 0.3 to 1.1 m3/ha in the dry zone (6).
1.2 Plantations
1.2.1 Introduction
To compensate for the loss of natural forests, and to increase forest yield, large scale plantations have been established with proven exotic species adapted to local soil and climatic conditions. Planting programme was first intensified in 1958 and again in 1964. In 1970 a long term Forestry Development Plan was drawn up with emphasis on large scale afforestation-reforestation. In building up the plantation forest estate, the following points have been taken into consideration:
the need to compensate for the production of those forest lands that must necessarily come under agriculture development;
the timber potential of the plantations in the dry zone which is up to 40 times more than that of the degraded natural forests;
the necessity to convert those natural forests intrinsically poor and degraded in more productive plantations, the conversion being restricted to areas where it is not necessary to maintain the existing natural forests for conservation and aesthetic purposes;
the possibility of raising forest plantations on land considered marginal for agriculture;
the silvicultural as well as the industrial criteria to govern the choice of species.
Most of the plantations are located in forest reserves, and the rest on other state lands treated as reserved land. They are for the major part established in the dry zone with teak and eucalyptus. About 4 500 ha are planted annually under the taungya system, locally called “chena”. In this system a block of about 2 ha of forest fallow or deforested area is temporarily leased to one family for reforestation and cultivation of food crops. The duration of agricultural crops depends on the tree species among other factors. For instance cropping can last three years in general under teak plantations.
A special programme of fuelwood plantations was started in 1979.
1.2.2 Areas of established plantations
Industrial plantations
Except for the fuelwood plantation programme mentioned above the existing plantations have been raised specifically for industrial purposes. Extent of area planted is well documented ((5) (6) (7) (9)) but information on survival/success rates has not been found. It has been estimated tentatively at 70 percent in average, taking into account the intensity of management of the plantations. The majority of the plantations have been established with teak which is grown in the dry and intermediate zones. Eucalyptus grandis is planted in the mountainous areas whereas E. camaldulensis is planted in the dry zone and the lowlands. At intermediate and high elevations, poorly stocked areas and grasslands are planted with Pinus caribaea var. hondurensis (which constitutes about 90 percent of the pine plantations), other pines being P. patula and some P. merkusii planted at lower altitudes. Other species planted include Araucaria cunninghamii, Albizia moluccana, mahogany (Swietania macrophylla), Alstonia, Cedrela toona, Casuarina equisetifolia and bamboo (Dendrocalamus strictus).
Areas of established industrial plantations estimated at end 1980 1
(in thousand ha)
Category | Species | Years | 76–80 | 71–75 | 66–70 | 61–65 | 51–60 | 41–50 | before 41 | Total |
Age class | 0–5 | 6–10 | 11–15 | 16–20 | 21–30 | 31–40 | >40 | |||
PHL 1 | Tectona grandis, Swietenia macrophylla, and others 2 | 39 (27.3) | 16 (11.2) | 19 (13.3) | 4 (2.8) | 3 (2.1) | 4 (2.8) | 4 (2.8) | 89 (62.3) | |
PHH 1 | Eucalyptus spp., Albizia moluccana and others 1 | 29 (20.3) | 22 (15.4) | 2 (1.4) | 5 (3.5) | 2 (1.4) | 2 (1.4) | 1 (0.7) | 63 (44.1) | |
PH. 1 | Subtotal broadleaved species 2 | 68 (47.6) | 38 (26.6) | 21 (14.7) | 9 (6.3) | 5 (3.5) | 6 (4.2) | 5 (3.5) | 152 (106.4) | |
PS. 1 | Pinus caribaea var. hondurensis other pines, Araucaria cunninghamii | 4 (2.8) | 3 (2.1) | 1 (0.7) | 8 (5.6) | |||||
P..1 | Total industrial plantations | 72 (50.4) | 41 (28.7) | 22 (15.4) | 9 (6.3) | 5 (3.5) | 6 (4.2) | 5 (3.5) | 160 (112.0) |
1 Figures in brackets indicate the estimated survival at 70%.
2 Breakdown by age classes prior to 1965 is only tentative.
Other plantations
The plantations raised on denuded hills will serve also the purpose of soil and environment conservation but are essentially industry oriented and therefore described in the preceding paragraph. Plantations aiming essentially at fuelwood production have been recently started and the present areas is less than 500 ha (at end 1979 there were 86 ha only).
Rubber plantations (243 000 ha) and coconut plantations (506 000 ha) are worth mentioning as tree plantations although they are not accounted for as forest plantations in this study.
1.2.3 Plantations characteristics
Mean annual increment and rotation of some important species, as given in document (10) is reproduced as under.
Plantation characteristics (10)
Species | Rotation years | M.A.I. m3/ha/year | Use |
Tectona grandis | 60–70 | 8.6 | Timber, transmission poles |
Swietenia macrophylla and Cedrela toona | 35–40 | 4.8 | Timber |
Alstonia macrophylla and Melia composita | 15–20 | 10.2 | Transmission poles (Alstonia) Timber for ceiling boards (Melia) |
Albizia moluccana | 10–15 | 14.3 | Matchwood, packing wood, tea chest, battens |
Eucalyptus grandis | 10–15 | 28.5 | Fuelwood |
10–15 | 21.3 | Pulpwood | |
15–20 | 25.5 | Transmission poles | |
35–40 | 14.3 | Timber | |
Pinus caribaea var. hondurensis | 10–15 | 14.9 | Pulpwood |
35–40 | 11.9 | Timber | |
Pinus patula | 10–15 | 18.6 | Pulpwood |
35–40 | 11.9 | Timber |
2. Present trends
2.1 Natural woody vegetation
2.1.1 Deforestation
Deforestation in the country constitutes a very serious problem. More than 40% of the forests have been lost during the last two decades. With the heavy population pressure prevailing throughout the country extension of agriculture at the expense of the forests cannot be stopped. Forest land has been alienated also for development projects. There is no likelihood that these trends of deforestation will change significantly although the government decided in 1973 that there should not be any alienation of natural forests in the wet zone. Some areas have indeed been recently alienated from this zone as indicated in (5), (6), (7) and (9). In the dry zone about 260 000 ha of forests will be lost during the next few years under the Mahaveli irrigation project through systematic clearfelling (9). It is estimated that until recently shifting cultivation extended by 8 to 10 000 ha every year. During the last years the practice has been declining with the introduction of the “chena” system of plantation (see section 1.2.2). Such plantations cover about 4 500 ha per annum. Loss of forest on account of shifting cultivation should however continue at the reduced rate of about 5 000 ha/year. On the basis of excision of forest land during 1974–76 (6) and 1977–79 (5) (7) (9)) and taking into account the “chena” system, shifting cultivation and the Mahaveli project, annual rates of deforestation have been estimated and are presented in the following table.
Average annual deforestation
(in thousand ha)
Periods | ||||||||||
1976–80 | 1981–85 (projections) | |||||||||
NHCf1uv | NHC1uc | NHCf1 | NHCf2 | NHCf | NHCf1uv | NHCf1uc | NHCf1 | NHCf2 | NHCf | |
ε | 21 | 21 | 4 | 25 | ε | 45 | 45 | 13 | 58 |
2.1.2 Degradation
Overexploitation of the forests through illegal fellings for fuelwood and timber, overgrazing and frequent fires result in significant reduction of growing stock, loss of natural regeneration and damage to forest soils. However the exact extent of this degradation and its consequences have not been assessed.
2.1.3 Trends in forest utilization
A decrease in wood production from the wet zone forests is to be expected in the near future as more and more areas are being declared as protection forests. However the loss will be more than compensated through salvage logging operations on an annual average of about 50 000 ha of dry zone forests to be alienated under the Mahaveli project. This will mean an annual additional production of about one million m3 of wood.
2.1.4 Areas and growing stock at end 1985
The considerations of the preceding sections together with area and growing stock estimates at end 1980 lead to the estimates of the following tables.
Areas of natural woody vegetation estimated at end 1985
(in thousand ha)
NHCf1uv | NHCf1uc | NHCf1 | NHCf2i | NHCf2r | NHCf2 | NHCf | NHCa | NHc/NHO | nH |
12 | 988 | 1000 | 175 | 193 | 368 | 1368 | 788 | 215 |
Growing stock estimated at end 1985
(in million m3)
NHCf1uv | NHCf1uc | NHCf1 | NHCf2 | NHCf | |
VOB | VAC | VOB | VOB | VOB | VOB |
2.4 | 0.7 | 59 | 61.4 | 7.4 | 68.8 |
2.2 Plantations
The following trends are envisaged from 1981 to 1985 (9):
increase of the present annual rate of industrial plantations (P..1) from 8 000 ha to 24 000 ha;
about 2 000 ha annual plantations carried out under “social forestry” and “integrated district development projects”, mainly for fuelwood (PHH 2);
fuelwood plantations at the annual rate of 2 800 ha and plantations for improvement of degraded catchments at the annual rate of 1 200 ha (PHH 2).
Because of the many constraints faced (especially lack of trained personnel (9)) it has been assumed that only about half of the targets indicated would be met in 1985 in the form of successfully established plantations, i.e. 50 000 ha of industrial plantations (P..1) and 15 000 ha of non-industrial plantations (PHH 2).
Areas of established industrial plantations estimated at end 1985 1
(in thousand ha)
Category | Species | Years | 81–85 | 76–80 | 71–75 | 66–70 | 56–65 | 46–55 | before 46 | Total |
Age class | 0–5 | 5–10 | 11–15 | 16–20 | 21–30 | 31–40 | >40 | |||
PHL 1 | Tectona grandis, Swietenia macrophylla and others | 30 | 39 (27.3) | 16 (11.2) | 19 (13.3) | 6 (4.2) | 4 (2.8) | 5 (3.5) | 129 (92.3) | |
PHH 1 | Eucalyptus spp., Albizia moluccana | 20 | 29 (20.3) | 22 (15.4) | 2 (1.4) | 6 (4.2) | 2 (1.4) | 2 (1.4) | 93 (64.1) | |
PH. 1 | Subtotal broadleaved species | 50 | 68 (47.6) | 38 (26.6) | 21 (14.7) | 12 (8.4) | 6 (4.2) | 7 (4.9) | 222 (156.4) | |
PS. 1 | Pinus caribaea var. hondurensis, other pines and Araucaria cunninghamii | 5 | 4 (2.8) | 3 (2.1) | 1 (0.7) | 13 (10.6) | ||||
P..1 | Total industrial plantations | 55 | 72 (50.4) | 41 (28.7) | 22 (15.4) | 12 (8.4) | 6 (4.2) | 7 (4.9) | 240 (167.0) |
Areas of established non-industrial plantations estimated at end 1985
(in thousand ha)
Category | Species | Years | 81–85 | 76–80 | 71–75 | 66–70 | 56–65 | 46–55 | before 46 | Total |
Age class | 0–5 | 5–10 | 11–15 | 16–20 | 21–30 | 31–40 | >40 | |||
P.2=PHH 2 | Fast-growing hardwood species | 10 | 0.3 | 10.3 |
1 Figures in brackets indicate the estimated survival at 70%
2 Breakdown by age classes prior to 1955 is only tentative
All plantations
Areas of established plantations estimated at end 1985
(in thousand ha)
Years | 76–80 | 71–75 | 66–70 | 61–65 | 51–60 | 41–50 | before 41 | Total | ||
Age class | 0–5 | 6–10 | 11–15 | 16–20 | 21–30 | 31–40 | >40 | |||
PHL | Hardwood species other than fast-growing ones | 30 | 39 (27.3) | 16 (11.2) | 19 (13.3) | 6 (4.2) | 4 (2.8) | 5 (3.5) | 129 (92.3) | |
PHH | Fast-growing hardwood species | 30 | 29.3 (20.6) | 22 (15.4) | 2 (1.4) | 6 (4.2) | 2 (1.4) | 2 (1.4) | 103.3 (74.4) | |
PH | Sub-total hardwood species | 60 | 68.3 (47.9) | 38 (26.6) | 21 (14.7) | 12 (8.4) | 6 (4.2) | 7 (4.9) | 232 (166.7) | |
PS | Softwood species | 5 | 4 (2.8) | 3 (2.1) | 1 (0.7) | 13 (10.6) | ||||
P | Total all plantations | 65 | 72.3 (50.7) | 41 (28.7) | 22 (15.4) | 12 (8.4) | 6 (4.2) | 7 (4.9) | 250.3 (177.3) |
Bibliography
(1) Gaussen, H. et al. 1965 “Notice de la feuille Ceylon” - Carte internationale du tapis végétal et des conditions écologiques à 1/1 000 000 - Extrait des travaux de la section scientifique et technique de l'institut français de Pondichéry-Hors série No. 5
(2) Hunting Survey Corporation Ltd. 1961 “Six Forest Inventories in the Tropics No. 2. Ceylon” - based on the work of R.G. Ray in collaboration with Canadian International Development Agency - Ottawa
(3) FAO 1974 “Travel Report” - Advisor's Assignment Report No. 6 - Project No. RAS/72/125 - Rome
(4) Perera, W.R. 1974 “Country Report of Sri Lanka” - prepared for Technical Conference on Tropical Moist Forests - Colombo
(5) Forest Department 1977 “Administrative Report of the Conservator of Forests for 1977” - Government of Sri Lanka - Colombo
(6) Forest Department 1977 “National Progress Report on Forestry 1974–1976” - submitted at Asia Pacific Forestry Commission, Tenth session - Colombo
(7) Forest Department 1977 “Administrative Report of the Conservator of Forests for 1978” - Colombo
(8) UNDP/FAO 1978 Report of the Formulation Mission for Regional Forest Industries Advisory Group - Rome
(9) Forest Department 1979 “Administrative Report of Conservator of Forests for 1979” - Colombo
(10) Forest Department 1979 Reply to questionnaire for FAO/UNEP Tropical Forest Resources Assessment Project - Letter of 12 November 1979 from Conservator of Forests to FAO Representative - Colombo
(11) Chandrasekharan C. 1979 “General Information about Forests and Forestry in Sri Lanka” - FAO Regional Office - Bangkok
(12) Tran Van Nao 1979 “Travel Report” - Rome
(13) Vivekanandan, K. 1980 “Energy Plantations” - prepared for seminar on Energy in Sri Lanka - Colombo
Thailand covers an area of 513 517 km2 between latitudes 5°45' and 20°30' North and longitudes 97°30' and 105°45' East. The main geographic regions are:
the Northern region which consists of a series of parallel and longitudinal fold mountains extending through peninsular Thailand into Malaysia. The average height of the peaks is 1 600 m with some above 2 000 m. Between these ridges lie relatively flat basins in which flow the four major tributaries of the Chao Phraya, Thailand's main river: the Mae Ping, the Mae Wang, the Mae Yom and the Mae Man. The alluvial soils of these basins are fertile. The region has a mild dry climate;
the Northeastern region with the Khorat plateau is separated from the Central plateau by the Don Phraya mountains. The elevation of the plateau varies between 130 and 200 m while the mountains in the west are between 800 and 1 300 m and the southern edge of the plateau averages about 400 m with peaks up to 700 m. The plateau gently slopes eastwards towards the Mekong river but fairly abruptly northward towards the Mae Nam Mun. Most of the plateau consists of sandstone, which is the parent material of the sandy soils on the plateau. Some alluvial tracts are scattered along the courses of the two major rivers, the Mae Nam Mun and the Mae Nam Chi and of their tributaries and they constitute the major agricultural areas;
the Central plain region is the largest and can be subdivided into three physiographic subregions:
the southeastern subregion is much dissected by southerly flowing rivers and flanked in the east by hills. The alluvial streams are utilised for rice cultivation, the higher and well-drained grounds for plantations and orchards;
the northern rolling plains subregion where the northern rivers flow together into the Chao Phraya. This area is in general fertile;
the Chao Phraya delta subregion is generally flat and usually flooded in the wet season. It is the largest and most fertile lowland area of the country, almost completely under cultivation, except for the mangrove, and is composed of silt brought down by the rivers. Bangkok is situated in this delta;
the Southern region corresponds to peninsular Thailand and is composed of mountains, in the west, up to 1 000–1 500 m and flat land. Streams flow eastwards towards the Gulf of Thailand and often have built up deltas, suitable for wet rice cultivation.
Thailand has a monsoonal climate with a wet season (90% of the annual rainfall) from April to September during the southwestern monsoon and a dry season from October to May with dry continental northerly winds. During the dry season Thailand is also influenced by the southern asiatic cyclonic storm belt which brings irregular amounts of additional rain. Annual rainfall is highest in the southern and western parts of the peninsular region and in the Southeastern region (from 2 000 to more than 3 000 mm) and is lowest (less than 1 000 mm) on the Central plain which in fact lies in the rain shadow of the western mountains. The Northeastern region has an average rainfall from just more than 1 000 mm in the west to more than 2 000 mm in the northeast. Temperature variations are small in the Southern and Southeastern regions, around an average of 28°C. Temperatures in Bangkok vary between 16°C in December and 35° C in April. Winter temperature in the north can fall to approximately 10°C or lower.
In 1979 the population was estimated at 46 347 000, with an annual growth rate of 2.9% from 1970. 75% of the economically active population work in agriculture (FAO Production Yearbook, 1979). The main crop is rice with a production of 15.6 million tons but there is a continued slow down in the growth of rice while other crops have continued to rise at 6% per year. Gains in output of agriculture have come through unorganized encroachment on forest lands. Only 20 percent of the total rice area receives controlled irrigation. During the past years the area sown to rice has increased, particularly in the northeast. Rubber is the main tree crop with about 1 350 000 ha planted in 1979. Ranching is relatively unimportant and does not occupy large areas.