4.1 Harvest from forest plantations
4.2 Future forest plantation harvest scenarios
4.3 Scenario comparisons: FAO - ABARE/Jaakko Poyry
4.4 Landuse implications
Several recent modelling efforts have made assessments of the current contribution of plantation wood to global wood supplies. FAO (2000) uses an assessment of mature age-class potential to estimate that year 2000 industrial roundwood production from forest plantations will be 414 million cubic metres. An assessment made by ABARE/Jaakko Poyry (1999), based on existing plantation area, estimates year 2000 production to be 624 million cubic metres.
Figure 4 shows regional estimates of proportionate contribution of plantation wood to regional wood supply made by FAO and ABARE/Jaakko Poyry. There are significant differences in the estimates, partially because significantly different base data has been used in the modelling process, and because the modelling techniques used are also considerably different. As noted above, use of age-class data as a basis for modelling adds a timing dimension to the FAO estimates. Thus, the relatively high proportion of immature plantation forests mean the FAO estimates will be, ceterus paribus, generally lower than the ABARE/Jaakko Poyry estimates, although not in the case of Oceania. Other significant differences in the estimates result mainly from the base plantation area estimates used. In comparison with the FAO data, the ABARE/Jaakko Poyry estimate uses significantly higher estimates of plantation areas for Europe and South America, and significantly lower estimates for Asia and Africa. Assumptions on mean annual increments and rotation lengths have significant, but lesser, effects on the estimates.
The "bottom-line" of the estimates suggests that current plantation production for industrial purposes is probably supplying 27-35 percent of the global industrial roundwood harvest. Forest plantation production for industrial roundwood is particularly important in the Oceania region, where 55-85 percent of industrial roundwood is plantation-grown. South America (32-63 percent) and Asia (32-41 percent) also have above average proportions of industrial roundwood produced in plantation forests. Production from forest plantations in a handful of countries in each of these regions - Australia, New Zealand, Chile, China, and Japan - is sufficiently large to put these regions ahead of the global average.
Figure 4: Comparative estimates of regional forest plantation wood supplies as percent of total roundwood harvest - 2000
Sources: FAO (1999),ABARE/Jaakko Poyry (1999)
FAO has modelled three scenarios for future wood supply from forest plantations as part of the Global Forest Products Outlook Study Thematic Study on Plantations. The three forest plantation scenarios are:
Scenario 1 provides a baseline forecast, by assuming that forest plantations are not expanded beyond their current area and that all areas are replanted after harvesting.
Scenario 2 assumes that new planting will increase the forest plantation area at a constant rate of 1.2 million ha per annum in total (equal to 1% of the current area of forest plantations).
Scenario 3 assumes that the annual rate of new planting estimated in 1995 (4.71 million ha in total) is maintained until the year 2010, after which it is reduced by 940,000 ha at the start of each of the following decades (i.e. until it declines to zero in 2050).
Figure 5: Comparison of projections for industrial round-wood production with three plantation scenarios
FAO, 2000Figure 5 compares future wood production to 2050 from industrial plantations under each of the three scenarios to forecast industrial roundwood consumption, derived using long-term trend analysis. Several points of interest can be noted from Figure 5.
1. There is little difference between the three forest plantation scenarios until 2010. This is because trees already planted will determine production over the next decade.2. The heavy weighting towards the youngest age-classes in the global distribution means that even with Scenario 1 (zero new planting) there is a substantial increase in wood production from forest plantations. Scenario 1 shows an increase in production from 331 million to 712 million m3yr-1. Note, however, this growth in plantation production would be insufficient to keep pace with the forecast growth in roundwood consumption, and additional new sources of wood or fibre would need to be found to supply additional new demand.
3. In Scenario 2 the output increases at approximately the same rate as projected new demand for roundwood. For Scenario 2 plantation wood production by 2050 increases to 906 million m3yr-1. Note, however, that current levels of harvesting in natural forests, recycling, etc. would need to be maintained if no other new fibre sources are found, or efficiency is not significantly improved.
4. Only Scenario 3, with its relatively large landuse implications, would enable forest plantations to substitute for wood production from natural forests. Scenario 3 expands plantation production to 1.5 billion cubic metres, approximately equal to current levels of global industrial roundwood consumption. Under Scenario 3, the industrial forest plantation share of industrial roundwood production is estimated to increase from the current 27-35 percent, to 64 percent in 2050.
It is interesting to compare the FAO future scenarios, and those developed by ABARE/Jaakko Poyry. It is readily apparent that these alternative forecasts lie toward the high end of the FAO range of forecasts. The ABARE forecast for 2020 is very marginally below the FAO Scenario 3, while the forecast for 2040 is approximately midway between the FAO Scenario 2 and Scenario 3. Thus, while there remain significant differences between regional components in the estimates, the overall magnitudes of the estimates are not dissimilar.
Table 2: Percentage share of plantation production in total industrial roundwood production - FAO Scenarios compared with ABARE/Jaakko Poyry.
|
Plantation Scenario |
FAO |
ABARE/JP |
|||
|
2010 |
2020 |
2050 |
2020 |
2040 |
|
|
Scenario 1 |
30.6 |
32.5 |
29.6 |
44.0 |
46.0 |
|
Scenario 2 |
31.2 |
35.1 |
37.0 |
44.0 |
46.0 |
|
Scenario 3 |
34.1 |
46.5 |
64.0 |
44.0 |
46.0 |
Sources: FAO 2000, ABARE/Jaakko Poyry 1999
The long-term production forecasts for forest plantations are mainly dependent on assumptions made about future establishment rates. Consequently, future availability of land for new planting, and perceptions of supply-demand balances for wood and fibre, will be key variables in determining plantation production. Given the financial imperatives driving relatively short rotations, and the species that currently grow fastest in plantations, it should be expected that for the foreseeable future plantations will supply a high proportion of raw material supply to fibre based industries and for the production of utility sawntimber. High quality hardwood timbers, especially, are likely to continue to be produced mainly in natural forests, although plantation grown teak and mahogany are becoming increasingly important.
Several issues are likely to be of substantial importance in determining actual rates of plantation establishment. Perhaps most important will be the suite of government policies that impact on plantation establishment. A key change over the past 30 years has been national policy shifts away from centralised government planting programmes, with governments taking less direct means of encouraging tree planting (see also Working Paper FP/9). A variety of incentive policies, privatisation, management devolution and government promotions, have contributed to this change in a variety of countries. An important future trend, in at least some countries, may be a form of “private sector devolution” whereby forestry companies take a lesser role in plantation establishment, and outgrower-type schemes assume much greater importance (see Working Paper FP/11).
The land area requirements for each the FAO scenarios in terms of plantation establishment, by region and for major countries, are shown in Table 2.
Table 3: Industrial forest plantation areas under new planting scenarios (million hectares)
|
Country |
Area |
Area |
Area |
Area |
|
|
North and Central America |
18.9 |
18.9 |
29.3 |
43.2 |
|
|
|
United States |
18.4 |
18.4 |
28.5 |
41.2 |
|
South America |
5.4 |
5.4 |
8.4 |
13.6 |
|
|
Asia |
41.8 |
41.8 |
64.8 |
119.5 |
|
|
|
China |
17.5 |
17.5 |
27.1 |
68.3 |
|
|
India |
4.1 |
4.1 |
6.4 |
11.7 |
|
|
Japan |
10.7 |
10.7 |
16.6 |
12.4 |
|
Oceania |
2.7 |
2.7 |
4.2 |
5.7 |
|
|
Africa |
3.6 |
3.6 |
5.6 |
8.9 |
|
|
Europe |
8.7 |
8.7 |
13.5 |
15.3 |
|
|
Former-USSR |
22.2 |
22.2 |
34.4 |
28.0 |
|
|
|
Russian Federation |
17.1 |
17.1 |
26.5 |
21.1 |
|
WORLD |
103.3 |
103.3 |
160.2 |
234.2 |
|
Source: FAO (2000)Scenario 2 is notable for requiring relatively modest, and seemingly plausible, increases in plantation areas. For example, the 27.1 million hectares proposed for China in 2050 under Scenario 2 is markedly less than the 40.35 million hectares currently planned in China to 2050. Scenario 2 implies a 55 percent increase in the current global plantation forest estate. Plantation development is, however, unlikely to be uniform across countries. Countries such as Chile and New Zealand have, for example, achieved isolated increases in forest plantation areas of 5-10 percent in a single year. Other countries have gone for extended periods with little or no forest plantation establishment. South Africa, for example, is not encouraging further afforestation as it has a preference to maximise water yields from catchments. Conversely, Vietnam has targeted the development of a 5 million-hectare plantation estate (a trebling of the current). The impacts of subsidies and other incentives is likely to play a role in distorting competitive advantage in forest plantation establishment away from current patterns.
The areas implicit in Scenario 3 also seem to be generally achievable in physical terms. Institutional and policy constraints may, however, play a highly significant role in limiting planting below the indicated levels. Two notable cases are China and the United States, both of which would be required to maintain rates of plantation establishment higher (or for longer) than seems likely at present. Some of this “excess” planting could, however, be spread across other countries without markedly affecting the results of Scenario 3.
