Category Archives: Plantations

Evaluation of benefits that can be obtained from FSC certification

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K.M.T.S. Jayarathne and S.K.Pathirage

Forest Stewardship Council (FSC) is an international non-profit, multi-stakeholder organization established in 1993 to promote responsible management of the world’s forests. FSC offers a comprehensive set of universally applicable requirements for responsible forest management with its  10 Principles and 56 associated Criteria. Achieving FSC can be further divided into standard setting, independent certification and labeling of forest products. There are three types of FSC certifications. They are FM, CoC and Group Certification. Forest managers or owners who want to prove that their forest operation are socially beneficial and managed in an environmentally appropriate and economically viable manner can apply for forest management (FM) certification. FSC chain of custody traces FSC certified timber throughout the production chain.

The expenses for a successful certification of forest management can be divided into (i) costs for an enhancement of sustainability, (ii) costs for audits (these are controlled by third parties) and (iii) secondary costs (e.g. losses of stumpage revenues). All together, the effective costs for FSC certification my be between 2.6-19.1 •/ha. The costs and timescale for CoC certification vary depending on the size and complexity of the operation. It also depends on the range of products and processes.

The benefits of certification are for the most part indirect, although surely valuable. They can include a better professional image, improved worker safety and training, better records, more active public involvement, better morale among forest managers, enhanced knowledge for outreach and extension, better environmental management systems and greater timber prices or access to more markets. As part of receiving certification, we have had to make significant improvements in several areas, such as (1) establishing a transparent and consistent environmental management system and record keeping process for our forests; (2) improving training and record keeping for forest workers using equipment and chemicals on the forest; (3) improving our adherence to and implementation of state forestry Best Management Practices (BMPs); (4) enhancing or at least clarifying our polices regarding silvicultural prescriptions and utilization standards; (5) identifying natural areas and wildlife habitat requirements for management; (6) enhancing the forest data bases, GIS coverage, and allowable harvest levels; and (7) developing more explicit procedures for public involvement and input into forest management decisions. The aim of certification is to ensure that forest resources are managed to meet the Social, Economic and Ecological needs of present and future generations. FSC prohibits conversion of natural forests or other habitats into forest plantations, prevents the use of highly hazardous pesticides, avoid the cultivation of genetically modified trees (GMOs), and respects the right of indigenous or local people in the area and health & safety of the workers. Other than that certification ensure the provision of clean water, fresh air and even help combat global warming. It also protects food, medicine and important natural resources as well as biodiversity. When it comes to economic benefits, evidence of increased market access or price premiums is more circumstantial. According to information provided by UNECE and FAO, market price premiums between 12% – 20% can be obtained for FSC-certified sawn hard woods.

K.M.T.S. Jayarathne and S.K.Pathirage

Control Union Inspections (Pvt) Ltd., Colombo –7, Sri Lanka.

Comparison of wood quality of even-aged Teak (Tectona grandis L.f.) plantations in three districts of Sri Lanka

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D.P. Weerasinghe and H.S. Amarasekara

Teak is listed as a super luxury timber in Sri Lanka and it has a high demand from construction and furniture industries. Teak hardwood is highly durable. It is an exotic species and, almost all teak plantations are located in dry and intermediate zones of the country. There are about 35,000 ha of teak plantations and most of these plantations are managed by the Forest Department. These plantations are distributed throughout many administrative districts in the country. Despite of its importance as a high-demand species in the market, there have been limited or no research studies conducted to assess the wood quality of teak grown in different districts.

This study compares the wood quality of even-aged teak plantations in three districts of Sri Lanka, i.e., Anuradhapura, Kurunegala and Ratnapura teak from Ratkarawwa area (Ratnapura district) was specially selected for comparisons, since there is a general belief among people that Ratkarawwa produce superior quality teak in comparison to other teak growing areas of the country.

Quality of teak wood was assessed by analyzing specific gravity and percentage of heartwood. Ring width was taken as the indicator of growth rate.

Three 45-year old trees of 45 grown in state plantations were examined in this study. Sample disks were extracted at breast height from each tree. Ring width and specific gravity of each ring was measured. The mean ring width values recorded for trees from Anuradhapura, Kurunegala and Ratnapura districts (A=2.679mm, K=2.652mm, R=3.106mm) did not differ significantly. The mean specific gravity values of trees from three districts (A=0.6142, K=0.6587, R=0.6901) were statistically significant. It was also observed that there is no significant relationship between ring width and specific gravity in the three districts. Heartwood percentage and wood colour were also analyzed to illustrate wood quality.

Slightly higher specific gravity value and high heartwood percentage were observed in Ratnapura teak. Furthermore, growth rate is high in this area and it contributes towards gaining high timber volume.

According to timber characteristics investigated in this study, it can be inferred that Ratkarawwa area (Ratanapura) produce high quality teak in comparison to the other two districts and, economically good teak wood are produced by plantations in Ratanapura district. However, other areas are also capable of producing good quality teak timber.

D.P. Weerasinghe and H.S. Amarasekara

Department of Forestry and Environmental Science, University of Sri Jayewardenepura, Sri Lanka.

Estimation of biomass carbon of Eucalyptus grandis using IRS LISS III Satellite images in up country wet zone of Sri Lanka

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A. Gunawardena1, S.P. Nissanka2, N.D.K. Dayawansa3

There are vital needs to collect some necessary data on forest plantations to address the global climate change that includes carbon sink concept in Kyoto protocol. There are very rapid expansions of forest plantation in Asia-Pacific region and Sri Lanka also have a large extent of forest plantations such as Eucalyptus and other fast-growing species. Plantations and Plants may be viewed as “Carbon sinks” removing CO2 from atmosphere and oceans by convert it into biomass in stem, root and foliage. Biomass is assimilation and accumulation of carbon into organic matter determined by carbon fixation and carbon release, therefore, biomass can be predicted by modelling of carbon dynamics. Estimating woody biomass by allometric equations may be time-consuming, because of the need to remove sample trees at the target research site, and the cutting may adversely affect the site. Therefore, there is a need to develop methods for estimating the biomass of managed plantations at diverse sites simply with non-destructive methods.

Use of Satellite Images Vegetation Index (SIVI) models can processes the biomass estimation without tree destruction by taking forest stand parameters as inputs such as Diameter of breast height (dbh), total tree height, canopy cover percentage, and ground exposure and slope parameters. Therefore, this study is an attempt to develop satellite driven 3 vegetation models to estimate above ground biomass and carbon content of Eucalyptus grandis which cultivated in up country wet zone region of Sri Lanka. The Eucalyptus grandis sites are located in the Pattipola, Ohiya and Meepilimana areas in Nuwara Eliya district of Central Province of Sri Lanka. Stratified random sampling plots were selected to obtain forest stand parameters and another few plots were used to accuracy assessment. Trees were sampled by putting 25x25m temporary sample plots which matching to the satellite image pixel resolution (area 625 m2). Biomass and carbon stocks are estimated from DBH and combination of total height using locally relevant allometric equations.

The estimated above ground biomass and carbon content value of the each plot were correlated with developed satellite driven vegetation indices (Normalized Difference Vegetation Index (NDVI), Soil Adjusted Vegetation Index (SAVI) and Liner Transform Band). The results show the NDVI derived from IRS LISS III satellite image is significantly correlated with the above ground stored biomass carbon content than other two indices. Finally biomass and carbon content map was developed for the study area using IRS LISS III satellite images.

A. Gunawardena1, S.P. Nissanka2, N.D.K. Dayawansa3

1Postgraduate Institute of Agriculture, 2Faculty of Agriculture, University of Peradeniya, 3Faculty of Agriculture, University of Peradeniya, Sri Lanka

Forest woodland ecosystem: An insight into the addition of litter through teak plantation

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A. K. Mani, S. Manivasakan, S. Vijayabaskaran

Teak is an important tree species grown under plantation conditions for timber requirement. Being a deciduous tree, it favours for accelerated nutrient cycling. A field experiment was conducted in an eighteen year old teak plantation at Forest College and Research Institute, Mettupalayam, Tamil Nadu, India to study the litterfall, their composition and rate of decomposition. The litter collected were separated into leaf litter, flowers, fruits and twigs. All were subjected to decomposition by using nylon bag technique. The total annual litterfall accounted for 11,255 kg ha-1. Of the total litter, leaf fall in a year was 9216 kg ha-1 (81.9%) followed by 726 kg ha-1 (6.5 %) by twigs, 707 kg ha-1 (6.3 %) by fruits and 607 kg ha-1 (5.3 %) by the flowers. Among the litter components, flowers decomposed rapidly than the other components. The highest decomposition constant (K) was recorded for flowers (2.39) and the least for fruits (0.70). The per cent remaining of the absolute amount of dry matter of leaf litter, flowers, fruits and twigs after one year of decomposition was 17.3, 9.2, 49.5 and 19.6, respectively.

A. K. Mani, S. Manivasakan, S. Vijayabaskaran

Regional Research Station, Tamil Nadu Agricultural University, India

Growth, biomass and carbon accumulation among rubber (Hevea brasiliensis), teak (Tectona grandis) and mahogany (Swietenia macrophylla) A case study from 1 to 10 Years of Age Series

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N. Appuhamy1, L. Samarappuli2 and S. Karunaratne1

The study was conducted to compare the biomass accumulation and carbon stocks among rubber, teak and mahogany. Above Ground Biomass of each species were calculated using the allometric models. Mean total tree height of rubber, teak and mahogany were ranging from 0.87 m to 20.32 m, 3.41 m to 11.05 m and 1.65 m to 7.53 m, respectively, between 1 to 10 years of age. For height and age, regression logistic standard curves were fitted to teak, rubber and mahogany with the R2 of 0.845, 0.916 and 0.921 respectively. The mean dbh of rubber, teak and mahogany were varying from 2.19 cm to 19.63 cm, 1.97 cm to 12.84 cm and 1.75 cm to 8.14 cm, respectively, within the selected age series. Exponential curves for rubber (R2=0.976) and teak (R2=0.915) and logistic curve for mahogany (R2=0.913) were fitted for dbh vs. age. Mean total tree biomass and carbon stock in rubber were significantly higher from other two species in all selected age series, except first year; biomass and carbon stock varying 0.89 kg/tree to 262.61 kg/tree and 0.45 kg/tree to 131.30 kg/tree, respectively. For other two species, it was ranged from 0.74 kg/tree to 88.87 kg/tree and 0.37 kg/tree to 44.35 kg/tree for teak and 0.49 kg/tree to 23.83 kg/ tree and 0.24 kg/tree to 11.91 kg/tree for mahogany. For Biomass and age regression logistic, critical exponential and exponential standard curves were fitted to rubber (R2=0.965), mahogany (R2=0.862) and teak (R2=0.874). The relationship of Height vs. dbh showed a high degree of association for rubber (R2=0.918), teak (R2=0.859) and mahogany (R2=0.976). Moreover, the relationship of biomass vs. height recorded a high degree of association for rubber (R2=0.911), teak (R2=0.862) and mahogany (R2=0.962).

N. Appuhamy1, L. Samarappuli2 and S. Karunaratne1

1Department of Plantation Management, Faculty of Agriculture and Plantation Management, University of Wayamba, Sri Lanka 2Department of Soils and Plant Nutrition, Rubber Research Institute of Sri Lanka.

Timber production in high density planting of Hevea brasiliensis

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T.U.K. Silva , V.H.L. Rodrigo1, S.M.C.U.P. Subasinghe

The demand of natural rubber has increased continuously with the increase in population and living standards of the human being. Rubber plantations are also a major resource of timber and fuel wood. In order to meet the continuous increase in demand for latex, timber and fuel wood, the productivity of rubber plantations should be increased. Whilst producing high yielding clones for improved latex and timber yield per tree which is a long-term process in perennial crops, planting density could be adjusted to obtain high productivity in rubber plantations. The present level of planting density of rubber in Sri Lanka has been decided on the experiments conducted with the genotypes which are not in common use at the moment. Also, the optimum density should vary with different socio-economic conditions. Therefore, the present study was aimed to identify the suitable planting density for the recently developed and commonly used genotypes of rubber. This paper is focused to assess the timber production of rubber with respect to high density planting.

The experiment was set up in Ratnapura district of Sri Lanka in 1992. Rubber was planted in three high densities, i.e., 600, 700 and 800 trees per hectare, with the presently recommended level of 500 trees per hectare. Also, three genotypes (clones) i.e., RRIC 100, RRIC 110 and RRIC 121 were incorporated with the statistical design of split plot where the planting densities were laid as the main plots whilst clones were in the sub plots. Five trees in each sub plot were selected randomly and were used for the measurements of total tree height (TH), crown height (CH), thickness of the untapped bark (BT) and tree diameter at breast height at 11 years after planting (11 YAP). Thereafter, stem volumes were determined using Newton’s formula.

Both TH and CH did not vary significantly among planting densities tested. Though not statistically significant, there was a marginal decrease in tree diameter with the increase in planting density. Irrespective of the clone used, BT and mean merchantable timber volume per tree decreased significantly with increase in planting density. Nevertheless, this decline was compensated by increased number of trees in high densities resulting in comparable levels of merchantable volume per hectare among different densities. Total stem volume per tree remained same among four densities tested with that total stem volume per hectare increased significantly with the increase in planting density. Therefore, higher densities are more useful in the industries of fuel wood, pulp, MDF boards etc. Among the clones tested, the clone RRIC 121 outperformed in growth and timber production. The clone RRIC 110 was infected with Corynespora leaf disease hence showed poor performance in all densities. Despite the increase in total timber production with the increase in planting density, overall financial viability of different densities is to be assessed considering all cost components and valuing both timber and latex produced before making any firm recommendation.

T.U.K. Silva, V.H.L. Rodrigo1, S.M.C.U.P. Subasinghe

Rubber Research Institute of Sri Lanka Department of Forestry and Environmental Science, University of Sri Jayewardenepura, Sri Lanka.

Biomass estimation in some dry zone forests in Sri Lanka from Forest Inventory Data

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M.D.P. Kumarathunge and M.C.M. Iqbal

Tropical forests are a major sink for carbon dioxide produced globally. Estimation of above-groundbiomass of these forests is an essential aspect of studies of carbon stocks and the effects of carbonsequestration on the global carbon balance. Long term monitoring plots across several tropical dryevergreen forests in India, in the recent past, shows they are highly carbon dense ranging from 73.06 Mg ha-1 to 173.1 Mg ha1. In Sri Lankan forests, biomass estimates are confined to the wet zone forests and plantations.

To assess the carbon dynamics in Sri Lankan dry zone forests, as a pilot study, above-ground biomass in five dry zone forests were estimated using past forest inventory data from 1961. Our objective was to develop an above-ground carbon database for dry zone forests, which can be used to determine the

carbon dynamics in those forests. The data of published stand and stock tables from the five dry zone forests, Hurulu, Kumbukkan, Kantalai, Pallekelle and Madhu, were converted to above ground biomass using published allometric models. Estimated above-ground biomass ranged from a minimum of 75.7 Mg ha-1 in the Kumbukkan forest to a maximum of 129.6 Mg ha-1 in the Kantalai forest. The total aboveground carbon stocks ranged from 37.8 Mg ha-1 in the Kumbukkan forest to a maximum of 64.8 Mg ha-1 in the Kantalai forest. The average above-ground biomass for dry zone forests was 92.62 Mg ha-1. When compared with the wet zone estimates (eg.Sinharaja 336.8 Mg ha-1) the dry zone forests have lower above-ground biomass due to high disturbances, low tree density and other factors such as slow growth pattern of most of the tree species. However, present above-ground biomass estimates are not available for dry zone forests and estimates from this study can be considered as the above-ground carbon stock 1960’s. These estimates shall be presented to assess the carbon dynamics in dry zone forests of Sri Lanka.

M.D.P. Kumarathunge and M.C.M. Iqbal

Plant Biology, Institute of Fundamental Studies, Hantana Road, Kandy, Sri Lanka

Economic valuation of conservation of genetic resources of wild rice relatives : Assessing the preferences of adjacent community for conserving Oryza granulata in the Wavulpane area

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R. Dissanayake1, S. Guruge1, M. Udugama1, M.U. Jayasinghe1, U.A.D.P. Gunewardena2
R.P.L.C. Randeni and R.S.S. Rathnayake3

This study was aimed to achieve the specific objective of assessing the preferences of adjacent communities for utilization, benefit sharing and conservation of the genetic resources of Wild Rice Relatives (WRR) in Sri Lanka and to explore the capability of setting the priorities for conservation and management of WRR based on these preferences. The “Wavulpane” village located in the Rathnapura district was selected as the case as: (a) it was reported to be one of the growing areas for the WRR of Oriza granulata, and (b) there were no weedy rice problems prevailing in this village. The “Choice Experiment Models” (CEM) [i.e. stated preference method used to obtain Option Values for non-market goods by exploring the individuals’ stated behavior in a hypothetical setting] were applied. The data were collected from 50 individuals who were well aware of the presence and potential importance of this particular WRR through a Participatory Community Appraisal (PCA) carried out with the support of a structured questionnaire designed specifically for the CEM. Outcome of the Choice Experiment, which used a Fractional Factorial Design to array four attributes and three levels in the choice sets orthogonally, shows that an individual in an adjacent community was Willing-To-Pay nearly Rs. 82 per year for in-situ conservation of WRR. The need of the hour is, therefore, to develop appropriate policy and institutional framework that works for this task to which both short and long term policies as well as stakeholder participation should be guaranteed (i.e. research stations, universities, NGOs).

R. Dissanayake1, S. Guruge1, M. Udugama1, M.U. Jayasinghe1, U.A.D.P. Gunewardena2
R.P.L.C. Randeni and R.S.S. Rathnayake3

1Department of Agribusiness Management, Wayamaba University of Sri Lanka
2Department of Forestry and Environment Science, University of Sri Jayawardenapura Sri Lanka
3Ministry of Environment and Natural Resources of Sri Lanka.

Timber production in high density planting of Hevea brasiliensis

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T.U.K. Silva, V.H.L. Rodrigo, S.M.C.U.P. Subasinghe

The demand of natural rubber has increased continuously with the increase in population and living standards of the human being. Rubber plantations are also a major resource of timber and fuel wood. In order to meet the continuous increase in demand for latex, timber and fuel wood, the productivity of rubber plantations should be increased. Whilst producing high yielding clones for improved latex and timber yield per tree which is a long-term process in perennial crops, planting density could be adjusted to obtain high productivity in rubber plantations. The present level of planting density of rubber in Sri Lanka has been decided on the experiments conducted with the genotypes which are not in common use at the moment. Also, the optimum density should vary with different socio-economic conditions. Therefore, the present study was aimed to identify the suitable planting density for the recently developed and commonly used genotypes of rubber. This paper is focused to assess the timber production of rubber with respect to high density planting.

The experiment was set up in Ratnapura district of Sri Lanka in 1992. Rubber was planted in three high densities, i.e., 600, 700 and 800 trees per hectare, with the presently recommended level of 500 trees per hectare. Also, three genotypes (clones) i.e., RRIC 100, RRIC 110 and RRIC 121 were incorporated with the statistical design of split plot where the planting densities were laid as the main plots whilst clones were in the sub plots. Five trees in each sub plot were selected randomly and were used for the measurements of total tree height (TH), crown height (CH), thickness of the untapped bark (BT) and tree diameter at breast height at 11 years after planting (11 YAP). Thereafter, stem volumes were determined using Newton’s formula.

Both TH and CH did not vary significantly among planting densities tested. Though not statistically significant, there was a marginal decrease in tree diameter with the increase in planting density. Irrespective of the clone used, BT and mean merchantable timber volume per tree decreased significantly with increase in planting density. Nevertheless, this decline was compensated by increased number of trees in high densities resulting in comparable levels of merchantable volume per hectare among different densities. Total stem volume per tree remained same among four densities tested with that total stem volume per hectare increased significantly with the increase in planting density. Therefore, higher densities are more useful in the industries of fuel wood, pulp, MDF boards etc. Among the clones tested, the clone RRIC 121 outperformed in growth and timber production. The clone RRIC 110 was infected with Corynespora leaf disease hence showed poor performance in all densities. Despite the increase in total timber production with the increase in planting density, overall financial viability of different densities is to be assessed considering all cost components and valuing both timber and latex produced before making any firm recommendation.Key words: rubber, planting density, latex, timber, fuel wood

T.U.K. Silva1, V.H.L. Rodrigo1, S.M.C.U.P. Subasinghe2

1Rubber Research Institute of Sri Lanka

2Department of Forestry and Environmental Science, University of Sri Jayewardenepura, Sri Lanka.

Establishment of relationships of growth at 7 years old Mahogany trees with selected site factors in low country wet zone, using GIS as a tool

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K.R.A.H.A. Randeni and S.M.C.U.P. Subasinghe

Mahogany (Swietenia macrophylla) is an exotic tree, which is heavily adapted to the climatic conditions of wet and intermediate zones of Sri Lanka. Although the state sector manages mahogany with longer rotations, private sector expects to achieve the maximum timber yield within a shorter period. Due to the land scarcity, many of these mahogany plantations have been established in barren and rubber uprooted lands which were heavily degraded. Therefore the soil conditions and site factors directly affect the growth of the mahogany within short rotations.

The present study was carried out in a 7 years old mahogany monoculture plantation established in Gomaragala, in low country wet zone of Sri Lanka to find out the effect of soil and site factors to the mahogany tree growth. Extent of this forest is 20.7 ha and it is managed by a private plantation company. This forest has been divided into 2 lots for the purpose of administration and further divided into 240 plots of 20 perch each.

In order to identify the relationships, between growth and site factors, tree dbh and height were used as growth parameters. Slope, bedrock establishment and terrain were selected as selected site factors. The growth parameters (i.e.dbh and height) were measured for all the trees in plantation (one measurement from each plot). Slope and terrain as geographical parameters were measured of all 240 plots in the entire plantation.

Since the regression based methods were not adequate for both qualitative as well as quantitative parameter analysis, GIS based analysis used for the present study, using ArcView 3.3. In order to create digital maps, the survey plan of the selected forest was digitized and georeferenced using 10 ground control points collected by a GPS data receptor. Then the georeferenced base map was digitized to demarcate all the plots and other land marks. After that different maps were prepared in vector form separately for each parameter. However, for the analysis, all these vector layers were converted to raster

layers. Raster layers were then reclassified and overlaid (two or three layers at a time) with the growth parameters to identify the effects. Then map analysis was completed to make decisions regarding tree growth in different site factors.

Results revealed that there are significant relationships between tree growth and the selected site parameters. However, the best conditions for the mahogany tree growth in the particular area are the slope between 110-240, and shallow bedrock prevalence and stony terrain.

 

K.R.A.H.A. Randeni and S.M.C.U.P. Subasinghe

Department of Forestry and Environmental Science, University of Sri Jayewardenepura Sri Lanka.