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Indicative estimates of teak plantation standing volume
Diminishing supplies of teak timber from natural forests have, as already noted, contributed to the recent increase in teak plantation programmes. Will these new areas meet future demands? This section looks at the possible contribution of plantations to teak timber supplies.
The calculation of future availability of standing volume in planned teak plantations would seem simple enough - the factors in the equation for the calculation of standing volume are area, establishment rate, growth rates, and rotation. Unfortunately the values assigned to these factors are most often, if not always, imprecise, being derived from estimates or even expert opinion. The uncertainties surrounding the calculation of true values of figures for existing plantation areas have already been mentioned in Section 3 above, while the planned plantation programmes are subject to unknown political developments, as well as to such unknowns as the availability of land. Very little information is available on the existing age structure of teak plantations, although it is known that much, if not most, has been planted since 1980. Applying a blanket rate of mean annual increment country-wide involves assumptions about the uniformity of growth rates and ignores the local variability of soils and climate, while rotation lengths may be changed according to market conditions, developments in conversion technology, or economic conditions. Finally, future markets for high quality teak timber and veneer are likely to continue to be strong, but whether plantation-grown teak will be of sufficiently high quality remains unknown.
Despite these uncertainties and the unreliability of the figures thus derived the attempt has been made to obtain an indication of future supplies of teak timber from existing and planned plantation programmes, if only to see if such “ball-park” figures suggest that present policies are more or less likely to meet predicted future demand. Such indicative estimates are, however, neither reliable in the dictionary sense of being assured, nor in the sense of statistical confidence.
A model was developed to derive indicative estimates of future hardwood plantation standing volumes (Leech 1998), as part of a wider project to study hardwood plantations in the tropics and sub- tropics7. The model uses the factors of area, future establishment rate, growth rates, and rotation as listed above to estimate standing volumes by 10-year periods to 2050, but the factors are adjusted for uncertainty based on published information where available and expert opinion where not. One of the adjustment “modifiers” is for existing area while the other three cover new planting rates and volumes. They are:
• A reduction factor for reported plantation areas. Since the reported area often means “accumulated planted area”, which may be very different from the actual area existing, a reduction factor was applied to adjust the reported plantation areas, described in Section 3, Table 1. The reduction factor was derived either from inventories where available, or by expert opinion. It does not necessarily reflect the “true” figure. The figures in Table 1 were further adjusted to include only areas established for veneer- or saw-log production.
• A modifier to adjust the current rate of new planting as plantations mature and the new planting changes to replanting of logged plantation areas, or as land is no longer available for expansion. The value was based on expert opinion if sources with experience were available, but otherwise arbitrary values were used.
• A modifier to adjust the volume increment figure downwards for losses due to competition- induced mortality or other possible reductions, or upwards for possible increases due to tree breeding or better management practices.
• A modifier to adjust the volume for availability, that is to allow for the age structure of existing stands and for the unavailability of increment early in the rotation of new plantations, by partitioning the increment between the increase in standing volume and that available (from thinning) for use.
To further take account of the uncertainty of the indicative estimates, three scenarios were tested on the model by adjusting the volume increment estimates: a pessimistic scenario, with mai of 3m3/ha/yr, a realistic scenario of 5m3/ha/yr, and an optimistic scenario of 8m3/ha/yr.
Tissue culture teak plantation productivity is very high when comparing with stump plantation.so go for tissue culture teak plantation .
Regards
BALAKRISHNA MUTHUKURI
MOTHER AGRI BIOTECH INDIA PVT. LTD.
BANGALORE.
+919035003471
Diminishing supplies of teak timber from natural forests have, as already noted, contributed to the recent increase in teak plantation programmes. Will these new areas meet future demands? This section looks at the possible contribution of plantations to teak timber supplies.
The calculation of future availability of standing volume in planned teak plantations would seem simple enough - the factors in the equation for the calculation of standing volume are area, establishment rate, growth rates, and rotation. Unfortunately the values assigned to these factors are most often, if not always, imprecise, being derived from estimates or even expert opinion. The uncertainties surrounding the calculation of true values of figures for existing plantation areas have already been mentioned in Section 3 above, while the planned plantation programmes are subject to unknown political developments, as well as to such unknowns as the availability of land. Very little information is available on the existing age structure of teak plantations, although it is known that much, if not most, has been planted since 1980. Applying a blanket rate of mean annual increment country-wide involves assumptions about the uniformity of growth rates and ignores the local variability of soils and climate, while rotation lengths may be changed according to market conditions, developments in conversion technology, or economic conditions. Finally, future markets for high quality teak timber and veneer are likely to continue to be strong, but whether plantation-grown teak will be of sufficiently high quality remains unknown.
Despite these uncertainties and the unreliability of the figures thus derived the attempt has been made to obtain an indication of future supplies of teak timber from existing and planned plantation programmes, if only to see if such “ball-park” figures suggest that present policies are more or less likely to meet predicted future demand. Such indicative estimates are, however, neither reliable in the dictionary sense of being assured, nor in the sense of statistical confidence.
A model was developed to derive indicative estimates of future hardwood plantation standing volumes (Leech 1998), as part of a wider project to study hardwood plantations in the tropics and sub- tropics7. The model uses the factors of area, future establishment rate, growth rates, and rotation as listed above to estimate standing volumes by 10-year periods to 2050, but the factors are adjusted for uncertainty based on published information where available and expert opinion where not. One of the adjustment “modifiers” is for existing area while the other three cover new planting rates and volumes. They are:
• A reduction factor for reported plantation areas. Since the reported area often means “accumulated planted area”, which may be very different from the actual area existing, a reduction factor was applied to adjust the reported plantation areas, described in Section 3, Table 1. The reduction factor was derived either from inventories where available, or by expert opinion. It does not necessarily reflect the “true” figure. The figures in Table 1 were further adjusted to include only areas established for veneer- or saw-log production.
• A modifier to adjust the current rate of new planting as plantations mature and the new planting changes to replanting of logged plantation areas, or as land is no longer available for expansion. The value was based on expert opinion if sources with experience were available, but otherwise arbitrary values were used.
• A modifier to adjust the volume increment figure downwards for losses due to competition- induced mortality or other possible reductions, or upwards for possible increases due to tree breeding or better management practices.
• A modifier to adjust the volume for availability, that is to allow for the age structure of existing stands and for the unavailability of increment early in the rotation of new plantations, by partitioning the increment between the increase in standing volume and that available (from thinning) for use.
To further take account of the uncertainty of the indicative estimates, three scenarios were tested on the model by adjusting the volume increment estimates: a pessimistic scenario, with mai of 3m3/ha/yr, a realistic scenario of 5m3/ha/yr, and an optimistic scenario of 8m3/ha/yr.
Tissue culture teak plantation productivity is very high when comparing with stump plantation.so go for tissue culture teak plantation .
Regards
BALAKRISHNA MUTHUKURI
MOTHER AGRI BIOTECH INDIA PVT. LTD.
BANGALORE.
+919035003471
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