Tag Archives: Symposium 2008

Cleaner production opportunities in Small and medium scale wood processing and furniture manufacturing enterprises in Sri Lanka

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Cleaner production is a preventive business strategy designed to conserve resources, mitigate risks to human and environment, and promote greater overall efficiency through improved production techniques and technologies; including substituting different materials, modifying equipments and redesigning products. In addition to environmental, health and safety benefits many cleaner production techniques provide opportunities that produce a positive financial return. This paper ermines for; (1) identifying adverse environmental impacts of wood processing & furniture making (2) identify associated health & safety impacts, (3) opportunities for mitigating those impacts with an emphasis upon cleaner production strategies that may also provide financial benefits.

Walkthrough assessments (audits) were conducted in selected five small & medium scale wood processing and furniture manufacturing enterprises (SME) based industries in Sri Lanka. In auditing small meetings were held with management and their representatives and several workers were interviewed. Raw materials consumption, production & utility data were collected. Current operational level & environmental, safety & health practices were observed.

Adhesives formulations used in SME contain solvent releases to air & damages to the environment & health of workers. Volatile (planning & sanding of wood) are the main sources of air pollution. Wood preservatives & coating materials generate contaminated waste water as a result of drippage from wood surface leaking from drums that store & discard of used formulations. Identified two prominent sources of hazardous waste of this industry are paints & industrial solvents. Used florescent bulbs, chemical containers are also contributing for hazardous waste. Wood waste contributes problem of unsustainable timber use includes saw dust, shavings & end pieces & rejected timber. Inefficient sawing and cutting of wood, improper treating/storage practices and inadequate drying add more to the wood waste stream. Electricity consumption of the industry is high since machineries are powered with electricity, inefficient machineries, over designed machineries, air leaks from compressors, using bulbs for day time lighting contribute for higher energy consumption. Improper factory layout, poor attention on house keeping, poor arrangements in stores & waste management, lack of regular maintenance of machineries & equipments and poor attention on personal protective equipment (PPE) creates enormous problems of environmental, safety and health.
Use of less toxic alternatives for adhesives & coating materials, introducing new strategies for adhesive & coating material application and installing efficient dust collection system, introduce water bath for painting room will reduce air pollutions. Timber drying to satisfactory level, spray preservatives & coating materials on the wood using high velocity spray system (SVS), install drainage paths to divert rain water away from process water, store additives, solvents, wood treating chemicals with spill collection system, minimize drippage from sprayed on preservatives or coating materials prevent a risk of waste water production. Strategies for reducing paint & preservative waste, reuse of recovered materials, train spray gun operators in proper techniques, solvents and other chemical in closed containers prevent losses through evaporation and spillage and proper waste collection system enables reduction of hazardous waste. Train workers in efficient wood cutting techniques, redesigning of products, avoid over ordering, return unused/damaged or obsolete materials, designate central cutting area, promote new productive uses for wood scrap and waste wood as fuel for others reduce wood waste load. Good house keeping practices, proper waste management system and correct factory layout, regular maintenance of machinery and equipments will enhance the efficiency of the industry & reduce adverse impacts on environment, health & safety. Use direct sunlight for inner lightening in day time, regular maintenance of machinery & equipments, allocating effeicient machineries and introducing of alternative energy sources reduce energy consumption on significant level. Keep attention on PPEs, regular awareness & training programs for workers will prompt for better environmental, health & safety stands of the industry.

G.G.T. Chandrathilake
Department of forestry & Environmental Science university of Sri Jayewardenepura

Trends in water quality parameters for river Maha Oya

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Maha Oya, is one of the main rivers in Sri Lanka, much used for drinking water extraction. It flows through five important districts of Sri Lanka offering water through fourteen water supply intakes. Only three of the associated plants offer conventional treatment for water. Several small to medium urban centers are located on the main stem of the river and on tributaries. Hence, the river receives much organic waste from the upstream. Industrial discharges and harmful anthropogenic activities are common in the final 50 km stretch of the river. This study aims to find trends of water quality changes along the river and find out the reasons for them.

Records of water quality from Maha oya in years 2002 and 2003 during high and low flow rate conditions on six heavy metals (Cu, Cr, Pb, Mn, Cd, and Zn), COD and BOD along selected sampling locations were used to investigate the pattern of  water quality variation along the river.

These values were compared with the values obtained for the same parameters from same locations in year 2008 from January to December. The comparison shows that the heavy metal concentration of the river has decreased significantly the 2008. Values of BOD and COD show that there is only an insignificant reduction from past records.

Values obtained for heavy metals are significantly below the proposed standards of the Central Environmental Authority during the year. Furthermore values obtained for COD and BOD for the latter stretch of the river are comparatively higher than the standard value. There is a significant difference between the values obtained during the low and high flow rates of the year for heavy metals, COD and BOD.

C. D. K Pathirana, N. J G.J Bandara
Department of Forestry and Environmental science, University of Sri Jayewardenepura

Growth, morphological, anatomical, and physiological responses of canopy species to varied light environments.

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Growth, morphological, anatomical, and physiological characteristics of seedlings of three canopy species; Artocarpus nobilis Thw., Litsea gardneri Thw. and Myristica dactyloides Gaertn. were compared with variation to the light regimes in lowland tropical rain forest, southwest Sri Lanka. Seedlings were grown under four stimulated light environments; deep shade (50µmolm-2s-1), medium shade (350µmolm-2s-1), partial shade (800µmolm-2s-1), and full sun (1200µmolm-2s-1) found in Sinharaja rain forest. Seedling height and mortality were recorded at three months intervals. After one and half years of seedling growth, leaf photosynthesis and stomatal conductance were measured and leaf cross sections taken for anatomical measurements. Digital photomicrographs of leaf sections were taken for leaf morphology measurements. After two years of growth, seedlings were uprooted and dried at 800C and dry mass recorded for root, stem, and leaves. Mass ratios were calculated for leaves, roots, and stem.
Results showed significant difference between shade treatments for seedling growth morphology, leaf physiology, and anatomy.  Seedling mortality of study species were not affected by irradiance level except Litsea gardneri. Total dry mass of Artocarpus nobilis and   Litsea gardneri grown in medium and partial shade were significantly higher than those in deep shade and full sun treatments. Species showed different growth and growth allocation pattern in different shade treatments. There were significant differences between dry mass allocation to leaves, stem and root for all study species. Lower root mass ratios were recorded in deep with more allocation to leaf and stem in treatments that had lower amount of shade. Leaf anatomy between canopy species differ in several important ways that help explain their shade tolerance. All species produced higher or thicker leaf attributes in full sun treatment compared to the deep shade treatment. Typical sun- shade morphological responses to decreasing shade levels included increased stomatal density, decreased leaf number and specific leaf area. Lowest values of net photosynthesis were recorded for seedlings grown in deep shade. Highest values were  recorded for seedlings grown in intermediate shade treatment. Results indicate that light conditions between medium shade (350µmolm-2s-1) and partial shade (800µmolm-2s-1) are optimal for plant growth and should be considered in management and reintroduction effort for these species.

Bandumala S.H1, Singhakumara B.M.P2 & Ashton P.M.S3.
1Forest Department  2 Department of Forestry & Environmental science, University of Sri Jayawardenepura, Nugegoda, Sri Lanka
3 School of Forestry and Environmental Studies, Yale University, New Haven, U.S.A.

An empirical model for predicting dbh growth with age for Eucalyptus grandis

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Eucalyptus grandis Hill ex Maiden (rose gum) is commonly grown as even-aged monocultures in colder climates in the hilly region of Sri Lanka. Trees harvested from those plantations are used for sawn timber, railway sleepers and fuel. In order to manage those plantations, estimation of diameter growth is essential with age and therefore that was the objective of this study.

Data were collected from 26 plantations for the model construction covering the entire region, which is favourable for rose gum growth. According to the above objective, age was selected as the primary explanatory variable. A Site index was selected as a second explanatory variable where there were growth differences apparent due to different site qualities. After developing the theoretical model structures, the modelling process was divided into three stages. Variables were also transformed to different forms to obtain the best models. R2 values and standard residual distributions were used as preliminary evaluations.

At stage one, it was tried to build a simple (linear or exponential) model to predict the dbh growth using age as the only explanatory variable. However, this was not successful due to low R2 values and non-constant variances.

Data were partitioned due to site differences at stage two using a site index, i.e., top height/age. It was possible to identify three site types with mean index values of 2.4, 1.6 and 1.1. After that similar model structures were separately fitted to each site class to estimate different parameters. The selected linear models over-estimated the dbh values for the lower ages. The parameter associated with age for the exponential models always indicated an indefinite increase of dbh with age. In addition to the above two, logistic functions were also fitted at this stage. However, for the poor sites, it had large outliers. Therefore stage two was also not successful.

Finally it was decided to use stage three with pooled data. Exponential and logistic functions were modified at this stage with a site index as a second explanatory variable in addition to the age. However, other than top height/age index, a partially qualitative site classification (site class) was also used. Initial parameters required for the iterations in SPSS were decided by simply fitting exponential and logistic functions without the second explanatory variable. For the second variable it was assumed as 1. Models with partially qualitative site classes had to be removed due to having parallel distributions between three site types. Finally it was possible to select 7 best models based on R2 and residual distribution. All those models indicated a high modelling efficiency and minimum bias when tested. Then the estimated dbh values were fitted against an age series of 5 to 50 to identify the distribution and compatibility with biological reality. After all those evaluations, the model shown below was identified as the best model to predict the dbh growth for rose gum in Sri Lanka for all site types. When tested with the data reserved at the beginning of the study, this model proved its suitability for field use.

Subasinghe, S.M.C.U.P.
Department of Forestry and Environmental Science
University of Sri Jayewardenepura
Nugegoda, Sri Lanka
 

valuation of the effectiveness of the social forestry component of the Forest Resources Management Project (FRMP) in Kurunegala District

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The paper reports findings of an evaluation  of the social forestry component of  the Forest Resources Management Project of the Ministry of Environment  commenced in 2002 with the overall objective of improving forest management for environmental protection and sustainable utilization of wood.
Three Forest Ranges in Kurunegala District were selected  for the study ie Mahawa, Malsiripura and Galgamuwa.  The methodology included secondary data gathering from published reports, primary data gathering by way of questionnaires, focal groups discussions and key informant surveys. Questionnaire survey was carried out in 72 randomly selected households 32 each from Mahawa and Galgamuwa and 8 from Malsiripura to represent 95% of the total households participating in the Project. 30 households who are not participating in the Project were taken as the control. The project staff, officers in the Forest Dept, Divisional Secretary, village leaders and elders were also interviewed. Woodlots were measured for yield and species composition recorded.

In general, there was a marked decrease in forest related offences such as encroachments, illicit felling of timber in all the ranges in Kurunegala Division from 2005 onwards. The decrease was from 4.25 ha to 1.3 ha. 66% of long term lease agreements were enacted after the FRMP Project and  of them 52% were with women farmers. The supplemental income from agroforestry plots was more in the range Rs. 100,000 – 150,000 per year in general. A significant increase was shown in the total family income per year especially in the range of 200,000 – 400,000. While the persons having passed G.C.E. O/L was 23% before FRMP it increased to 43% after the project. The school drop outs or those who did not attend at all decreased from 16 to 10%. More employment was created in farming in the villages. Majority of the farmers were satisfied with the services provided by the Forest Dept staff. With regard to land degradation, all the respondents agreed that land degradation was curtailed after FRMP significantly. The FD staff had been trained well and the policies have also changed towards better sustainability. However, as the farmers were not well versed in forest management practices to obtain optimal yield the growth of the plots were rather inferior to the Forest Department plantations.

M.C.S. Kumarawardene* and D.M.S.H.K. Ranasinghe**
* Forest Department, ** Department of Forestry and Environmental Science, University of Sri Jayewardenepura

Evaluation of Social Forestry Component of the Sri Lanka Australia Natural Resource Management Project

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This reports the evaluation of the social forestry component of the  Sri Lanka Australia Natural Resource Management Project (SLANRMP) in the Kurunegala District. The main objective of this component was to contribute to poverty reduction through improved natural resource management in the dry and intermediate zone of Sri Lanka through community participation. 

The study focused on three forest ranges in Kurunegala District namely Mahawa, Galgamuwa and Malsiripura. Ihalathimbiriyawa village was selected from Mahawa Range while Dalapotugama and Katiyawa villages were selected from Galgamuwa and Malsiripura Ranges respectively. 30% of the households participating in the Project were selected from each forest range at random while those who are not participating were taken as control. Secondary data were collected from published reports while primary data were collected using questionnaire surveys, focal groups discussions and key informant surveys and field observations.

The project was able to reach more than 90% of the households in both Dalapotugama and Ihalathimbiriya villages while it was only 60% in Katiyawa village. In each village Community Based Organisation was functioning well and was registered with the Divisional Secretary. The participation of female members as Office Bearers was very high in all the villages (59-70%). The level of participation of the communities in project related work was highest in Ihalathimbiriyawa (95%) compared with others Dalapotugama and Katiyawa which was 60%. The extent of forest replanted/protected  and maintained was high in Dalapothagama and Ihalathimbiriyawa (107-192 ha) but this was much smaller in Katiyawa (42 ha). In all the three villages the occurrence of forest fires decreased  to none in the year 2007. With regard to availability  of water, more rainwater harvesting was significant after the Project. Although the total no of non agricultural activities did not change much, there was a market shift towards skilled labour after the project.

The main reason for participating in the project was for financial benefits  as well as protection of the village environment (26%). More group and individual savings with the project (95.6%). More credit sources introduced  which placed less reliance on the mudalali. More credits were taken for farming activities (43%) with the project as from only 4% without the project. Credit limits also increased from 10.5% to 52.3 % for the range Rs. 5000-20,000 which showed that the people’s livelihoods had enhanced significantly. The common mode of transport shifted from the push bike to motor cycle.
(40% to 64%).
The number of micro enterprises generated from the Project, especially the ones which are successfully continuing are rather few in all three villages (4-6% of the total households enrolled). However, loans had been applied for other enterprises and had been approved too. Apart from the Forest Department about 8 other agencies have established contacts with the communities with project related work. However, a major drawback experienced was  lack of forward market contracts which might be a deterrent to the sustainability of the Project.
H.D.P Sumanapala1  D.M.S.H.K Ranasinghe2 and Manoj Kumar Nathy31Forest Department, 2University of Sri Jayawardenapura, 3Sri Lanaka Australia Natural Resource Management Project

A quantitative study to propose effective guidelines for household composting

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Solid waste is a major environmental problem in Sri Lanka. The main disposal sites are marsh lands, low lands, river banks & other wet lands. More than 80% of the waste generated in Sri Lanka consist of organic materials. When compared to other developing countries there is a great possibility in composting the waste and getting a better solution to the waste problem in Sri Lanka. Therefore considerable attention is being now paid by the local authorities on household level composting programs to reduce the amount of municipal solid waste disposed from households.

The aims of the present study are to identify the problems associated with household composting programs and to give necessary guidelines to implement a successful composting program. In order to collect the data for the given aims, field observations were  made in three areas namely Katugoda and Magalle in Galle district and Bandiyamulla-East in Gampaha district where composting programs are implemented. A sample of ten percent of the total households was randomly selected to take the necessary observations. (Type of waste, Moisture level,Grade of compost etc.).

As an improper balance between ground waste and food waste inside the bin is observed in majority of households, a quantitative study of making compost was done using kitchen waste, ground waste and saw dust. An appropriate ratio was developed using the literature available and the particular ratio in field. Necessary measurements were taken from the compost made, after testing for eight weeks. (i.e pH value, moisture content, organic carbon content, Nitrogen content and Carbon to Nitrogen ratio)

A proper fixed ratio cannot be assign for food waste and ground waste as the compost making process is an art through experience rather than a scientific fixed method. The proposed ratio gives a proper balance for kitchen waste, ground waste and saw dust as the combination produce compost complying with the Sri Lankan standards in tested parameters. Quantities around the proposed ratio are favorable for a fairly better product.

Anthony C.S.C., Bandara N.J.G.J.
Department of Forestry and Environmental Science, University of Sri Jayewardenepura