There is global concern over the increasing rate of deforestation and forest degradation in the tropics. According to the latest FAO studies, the estimated annual rate of tropical deforestation was 15.4 million ha during 1981–90. Unprecedented population growth, need for agricultural land, imbalance in demand and supply of forest products and lack of economic development combined with political factors within and outside nations have been diagnosed as the main causative factors. To a certain extent deforestation is counter-balanced by the creation of plantations.
Plantations are by no means a panacea for deforestation nor can they replace all the functions of the natural forest. There are numerous examples where poorly planned plantations have failed or have degraded the site and affected the habitat adversely. Nevertheless, their contribution to arresting deforestation should not be underestimated.
In the developing countries, the launching of community forestry on a massive scale for planting trees outside forest reserves has given a new dimension to traditional plantation programmes. Besides producing various kinds of products and raw material for meeting both the basic needs of rural people and the commercial needs of wood based industries, it has helped in improving the rural income. China, Korea and India are outstanding examples of implementing community forestry on a massive scale. China has increased its forest cover from 9.2% to 13.0% (1989) in the last 40 years by adding 31.1 million ha through intensive plantation programmes (Anon, 1991). Tree planting in cities and towns is ameliorating the urban environment. In most of the industrialised countries the forest area and growing stock have either stabilized or have increased due to the establishment of plantations.
It is therefore essential to reiterate a few important properties of plantations.
The utilizable product of plantation forests is usually much higher than that of natural forests. Through the selection of appropriate fast growing species and provenances matched to the site, and improved management techniques, there is ample scope to increase the productivity of plantations even more. In many commercial plantations a yield of 15–30 m3/ha per year or even higher has been reached against 1–5 m3/ha per year in natural forests (Wiersum, 1984).
Plantations produce wood on short rotations of 7–30 years as compared to natural forest (30–150 years), and of more uniform size and quality. This uniformity facilitates harvest, transportation and conversion.
Plantations can be located wherever infrastructure and suitable land are available, near to the population centres or wood processing units thereby making them more easily accessible and reducing transportation cost.
The role of plantations in supplying the ever increasing world requirement of industrial wood has increased significantly over the years. The percentage of industrial wood produced from plantations compared to natural forests is presented in the table below for selected countries.
Production of industrial wood — Natural forest vs plantations
| Countries | Total Area (000 ha) | Share of Plantations (%) | ||
|---|---|---|---|---|
| Natural forests | Plantations (reported) | Forest area | Industrial wood production | |
| New Zealand | 6,270 | 1,200 | 16.1 | 93 |
| Brazil | 566,000 | 7,000 | 1.2 | 60 |
| Chile | 7,000 | 1,450 | 17.1 | 95 |
| Argentina | 33,900 | 780 | 2.2 | 60 |
| Zimbabwe | 32,300 | 70 | 0.2 | 50 |
| Zambia | 8,900 | 120 | 1.3 | 50 |
Forest rich countries like Indonesia plan to increase the share of plantations in the production of industrial wood from the present 20% to 80% by the year 2030 (Indonesia/FAO, 1990).
Due to increasing degradation and depletion of natural forests, rising environmental concern and the need to protect and conserve biodiversity, future forest plantations will be the only dependable resource to meet the world demand for industrial wood.
Traditionally, trees have been planted for the prevention of soil erosion, controlling water run-off in catchment areas, providing shelter against heat and wind and checking desertification.
Of late, the role of plantations as potential carbon sinks to help mitigate global warming is being increasingly studied. Growing trees store carbon through photosynthesis, with the carbon content amounting to about 45% of the stem's dry weight. Carbon sequestering is greater in young fast growing trees, which absorb more carbon per unit time, than in mature slow growing trees. Carbon-sequestering also varies according to the species, plantation site and management practice. Preliminary studies have indicated that application of modern forest management and agroforestry practices on a global scale could potentially sequester or store up to 10 billion tonnes of carbon annually as a one time effort (EPA, 1991). This study is based on the assumption that deforestation of the tropical forests will be reduced, management of the world's natural forests will be improved and plantation areas will increase by 15 million ha annually.
The definitions of plantations used in this study are those adopted on the occasion of the World Symposium on Manmade Forests and their Industrial Importance (1967):
Forest stands established artificially by afforestation on land which did not previously carry forests;
Forest stands established artificially by reforestation on land which carried forest within the previous 50 years or within living memory and involving the replacement of the previous crop by a new and essentially different crop.
Plantations established for the production of industrial roundwood play a vital role in the growing international trade in industrial wood and wood products. Therefore, plantations were further distinguished in this study according to industrial/non-industrial function, and the FAO (1982) definition has been adopted.
Industrial plantations are established totally or partly for production of wood for industry mainly as sawlogs and veneerlogs, pulpwood and pitprops.
Non-industrial plantations are established mainly for one or several of the following objectives.
It is not, however, always possible to draw a rigid line between industrial and non-industrial plantation areas. Since Forestry is a long term enterprise, plantations established for industrial purposes may have to be utilised for non-industrial purposes in future and vice-versa, due to changes in supply and demand dynamics, market forces, technological development or for other reasons.
FAO (1978) defines community forestry as any situation which intimately involves local people in forestry activity. It embraces a spectrum of situations ranging from the raising of woodlots in areas which are short of wood and other forest products for local needs, through to the growing of trees at farm level to provide cash crops. It may also include the processing of forest products at the household, artisan, or small industry level in order to generate income from the activities of forest dwelling communities.
The term social forestry, first came to prominence in the 1976 report by the National Commission of Agriculture in India to define a set of activities which encourage the growing of trees outside of the forest reserve, to supply fuelwood and other forest products to local people and to reduce the burden on production forestry. It has since been used interchangeably with community forestry in India and elsewhere.
Determining the area of plantations established under community forestry is beset with difficulty due to variations in the spatial arrangement of trees. Isolated trees are planted in homesteads and gardens, single or multiple rows along farm boundaries or road and canal sides and elsewhere in blocks. Many countries use a national factor to convert number of seedlings distributed into plantation areas but others report by number of trees planted or established.
Plantations established under community forestry/agroforestry have the main objective of meeting the local wood and fodder deficits and other service requirements like providing shade, shelter, etc. Such plantations have, therefore, been included as non-industrial plantations unless an industrial objective is specified by the reporting countries.
National developments in forestry plantations are often compiled annually by the department in charge of forestry and are published as official statistics. Such statistics are also quoted in progress reports of the national forestry sector and are presented to regional forestry commissions, international conferences etc. Reported areas in the present study are thus from official sources and/or presented to various commissions, conferences etc.
Net area means the actual existing plantation area which has been established successfully, estimated from plantation surveys as inventory or survival percentage.
The term survival percentage refers to the percentage of the total number of seedlings planted which have actually survived in a given area.
The term success percent (or net area) when used in this study means the percentage area of the reported plantations which has minimum stocking, say 60% of the initial planting, at the time of inventory.
In a plantation survey where only survival percentage has been determined, the net area has been derived by multiplication of survival percentage with reported plantation area. In a situation where mortality of the seedlings is not high (say below 40%) and they are evenly distributed, such a reduction in the plantation area is biologically not justified, because surviving seedlings may still provide acceptable stocking. But considering the present trend of calculating plantation area by converting seedlings distributed or planted in different spatial patterns into area by a notional number, by several countries, such a reduction, although arbitrary, has been used to reflect the losses that are known to have occurred in most plantation programmes.
Tree plantations which are usually outside the purview of the foresters' competence and having as a main objective the production of non-wood products like rubber, palm oil and coconut, are included in non-forestry plantation. These plantations are generally established and managed by agricultural or other non-forestry/private organisations. The records of such plantations are often not available with the department in charge of forestry in the country and are therefore not included in the total area of reported forestry plantations. Since non-forestry plantations have now become a potential source of industrial/non-industrial wood, area information, where available about such plantations, has been included and presented separately in the study.
In the last decade or so awareness of the importance of plantations has grown, especially in the tropical/developing countries. A large number of donors from the developed world, including international agencies, and investment banks have extended financial support to accelerate the activity. Investment in the forest plantations being high (on average US$1,000 per ha in tropical countries), a large amount of money is spent on establishing plantations. The World Bank has financed forestry projects in the developing countries worth about US$2.5 billion up to 1990; more than 50% of which has gone to plantation forestry (industrial as well as community).
As with the uncertainties in estimating the total area of natural forests and the annual rate of deforestation, a large gap exists in knowledge of the actual area of successfully established plantations and their growth/yield. Normally it should not be difficult to monitor plantation programmes compared to natural forest because every seedling planted with human activity can theoretically be accounted for and the area measured.
A large number of factors contribute to misleading figures concerning forest plantations, especially in the developing/tropical countries. The main reason is the lack of inventory or survey data of established plantations. Quite often plantation areas have been overestimated. Planting agencies have reported inflated planting area figures, failed/destroyed plantations have not been deleted from the records, replanting of the failed areas has been reported as new plantation and seedlings have been converted into area by some notional number without verifying actual plantation area on the ground.
Reports on growth and yield of the plantations have also been mostly over-optimistic. The existing yield tables prepared for fully stocked stands have been indiscriminately applied to estimate growth or yield of plantations which do not grow under comparable conditions. Plantation projects proposals often assume an ideal situation and overestimate the yield to get financial acceptance. Yield estimates extrapolated from the performance of young plantations are often misleading.
In other cases plantations have succeeded technically but their economic potential has not been fully realised, due to lack of proper planning and integration with end use. FAO, in its Tropical Forest Resources Appraisal of 1980 described comprehensively the plantation resource of the tropical countries. The net plantation area of 76 tropical countries in 1980 was estimated at 11.5 million ha and was projected to be 17.0 million ha in 1985. These plantation area figures were estimated on the basis of review of literature combined with personal information furnished by consultants. In general the plantation figures reported by the countries were reduced by an assumed survival percent based on experience.
In order to assess the actual plantation area and to evaluate its success and growth, some countries have carried out plantation inventories at national/sub-national or project level by employing governmental or independent agencies. But, in general there was found to be a lack of reliable information about plantation resources in tropical countries.
The study was organised in the framework of the Forest Resources Assessment 1990 Project which was intended to assist in providing guidelines for comprehensive and purposeful reporting of forest resource at national level.
The specific objectives of the study were to:
The focus of the study was the forestry plantation areas of the tropical countries. Countries having more than 50% of their land area between the Tropic of Cancer and the Tropic of Capricorn were included in the study and their entire plantations were considered. Selected non-tropical developing and a few developed countries where areas under forestry plantations were significantly large and their records were available, have also been included in the study for comparison.
Although high productivity is the primary intention of plantations, reporting of the actual growth and yield obtained from large scale plantations by the planting agencies/countries was very scarce. Therefore, only limited information about actual yields of the main species (eucalypts, pines and teak) is presented. The actual yield was compared with the optimum yield (obtained from PSP data) for each species and the potential yields of natural forests in the same geographic area or country, to indicate possibilities for yield improvement in the future.
The study was carried out as a desk study based on the systematic review of existing information.
Establishment of the time series data of forestry plantations of each country in a tabular form (appendix-I) was the first step in this study, and formed the basis for reported area assessment. Country reports were used as the main data source. Consistency was checked between different years of reports for each country to detect typing/printing errors, etc. In the absence of plantation data from countries like Bolivia, Ethiopia, Madagascar, etc, other sources indicating plantation rate or otherwise were used to estimate the plantation areas. Since plantation areas for most of the countries were reported at 1989 or earlier, the data for 1990 was estimated in most cases on the basis of historical trends in annual plantation rates during previous years or planned planting for 1990 and onwards.
The sources quoted in the time series data table always refer to the plantation areas in the reference years and only in a few cases to the species composition. In order to facilitate searching, the time series data references have been arranged country-wise in the bibliography section. Additional references available for a few countries only have been used to estimate the areas occupied by main species.
The information about plantation species composition was inadequate especially in the countries where large scale plantations were established under community forestry schemes. Therefore, composition of the main species was estimated based on other reports, articles and in a few cases as determined during previous years. For example, in the case of India, a survey report on survival of trees carried out in five representative states covering 30% of the national annual planting was analysed to extract the percentage composition of the main species. The percentage species composition in Brazilian plantations up to 1986 was extended to 1990.
Distinguishing industrial from non-industrial plantations proved to be particularly difficult in some countries due to ambiguous reporting and variation in classification. For example, Ghana reported 19,670 ha industrial plantation (1986 report) in 1984 and 60,762 ha in 1985 (1991 report) although there was no increase in total plantation area. In such cases the FAO's assessment of 1980 (country brief) or other sources were used. Plantations established under community forestry schemes have been classified as non-industrial.
In order to assess the annual plantation rate during 1981–90 at sub-regional, regional or global levels, the plantation area for each country was estimated to the reference year 1980, on the basis of time series data. For several countries this figure corresponded closely to the 1980 figures published by FAO. Where an author's estimate for 1980 is significantly different from that of FAO it has been pointed out in the regional analysis. Where time series data was inadequate for making a good reference year estimate, the area reported by FAO in 1980 has been used if found to match with the general trend within the country. To arrive at reported plantation area figures at global, regional and sub-regional levels, total area, and area by end use and species, each country has been treated as an individual study unit.
This was carried out using information available from both reported and net plantation areas from plantation inventory and survival reports to derive a regression function. While reviewing the inventory reports it has been found that some of the reports quote only the area actually determined (net area) through the inventory and not the reported area originally planted. In such cases, reported areas have been estimated or extracted from the country reports. Similarly, in the case reports giving only survival percentage, net planted area has been derived by multiplying reported area with survival percentage.
For estimation of net planted area, inventory results have been treated as sample observations. The regression line between reported and net areas has been drawn only to show the trend at global level and not for estimating the areas at regional or country levels. Estimates of total net planted areas and net annual plantation rates at global and regional levels have been done independently.
The review of actual growth and yield of main species in large scale plantations has been possible from detailed plantation inventory results, harvested yield of the species and area information furnished by the countries. Growth and yield data based on permanent sample plots (PSP), have been extracted from the author's previous work, (Pandey, 1983) supplemented by review of recent research reports. Potential yield of the natural forests for different countries has been derived from Paterson (1956), determined on climate vegetation productivity (CVP) index. Mean annual increment (MAI) of volume production at rotation age was taken as a parameter for comparing the actual yield, optimum yield derived from PSP data and potential yield of natural forests.
In discussing planning issues, only a few examples, each of different type, for both planned and unplanned plantations have been given, due to limited resources.
The study was funded by the Swedish International Development Authority (SIDA) and was carried out in close coordination with the Forest Resources Assessment (FRA) Project 1990 of FAO, in two phases. The duration of the first phase was about 14 man months from April 1991 to May 1992, with headquarters at the Forestry Faculty of Swedish University of Agricultural Sciences (SUAS), Umeå, out of which about three and half months was spent on travel for data gathering and discussion. The draft prepared during first phase was finalised in second phase of one month (duration September 1992) at FAO headquarters, Rome.
In order to accomplish the study the following inputs were employed.
The following institutions were visited to review the available literature:
More than thousand references were consulted in all, but only the relevant references have been included in the bibliography.
A large number of countries, institutions, international organisations and specialists were contacted by the author and by the FRA 1990 Project Coordinator, through correspondence for supplying comprehensive plantation data and plantation inventory reports.
Personal discussions were held with a large number of specialists at the institutions which were visited. To mention a few; subject matter specialists at FAO, World Resources Institute and the World Bank. Discussion was also held with country delegates at the 10th World Forestry Congress, Paris in order to obtain first hand information.
Technical support throughout the study was provided by the specialists at the Forestry Faculty, SUAS, Sweden and Forest Resources Assessment 1990 Project of FAO.
Anon. 1991. A brief introduction to China's forestry, Released to 10th World Forestry Congress
EPA. 1991. Assessment of promising forest management practices and technologies for enhancing the conservation and sequestration of atmospheric carbon and their costs at the site level, US Environmental Protection Agency, Environmental Research Laboratory, Corvallis, Oregon, USA
FAO. 1967: Secretariat note to the “World Symposium on man-made forests and their industrial importance”, Canberra 14–15 April 1967
FAO. 1978: Forestry for local community development, Forestry Paper 7, Rome, Italy
FAO. 1982. Tropical forest resources, Forestry Paper 30, Rome
Government of India. 1976: Reports of National Commission of Agriculture, New Delhi, India
Indonesia/FAO. 1990, Situation and outlook of the forestry sector in Indonesia, Volume 2: Forest Resource Base
Muthoo, M.K. 1991. Forestry in rural land use: A global synthesis, trees and forests in rural land use, Forestry Department, FAO, Rome
Pandey, D. 1983. Growth and yield of plantation species in the tropics, FAO Rome
Paterson, S.S. 1956. The forest area of the world and its potential productivity, The Royal University of Göteborg, Sweden Department of Geography
Wiersum, K. F. 1984. Strategies and design for afforestation, reforestation and tree planting, Pudoc Wageningen
World Bank. 1990: Investments in plantation forestry, personal communication
