Estimation of ecological footprint for Madurawala Divisional Secretariat area, Kaluthara District
By lakmali | February 5, 2010
W.D. Sepalika and U.A.D.P. Gunawardena
The Ecological Footprint calculates the combined demand for ecological resources and presents them as the global average area needed to support a specific human activity. This quantity is expressed in units of global hectares. Present resource utilization expressed by such indicators will be helpful to recognize the future trends. Main objective of the study is to calculate Ecological Footprint per person in the Madurawala Divisional Secretariat area under four major land-use types which are crop land, carbon uptake land, forest land and built up land. In addition, it was intended to estimate the relationship between the socioeconomic parameters of the community and the footprint.
Madurawala Divisional Secretariat area in the Kaluthara district was selected for the study. Stratified random sampling method was used based on the income level of the households. To collect primary data, two surveys were carried out. First survey involved collecting data using a diary kept at the households to obtain actual daily consumption data on food consumption, electricity consumption and traveling data. The diaries were distributed among 50 households and were recollected after a month. The second survey involved a questionnaire survey of 49 households focusing on the same consumption data and forest product consumption and built up area data. In addition, secondary data were collected from various sources.
The comparison of data obtained from diaries and questionnaires prove that there is no significant difference between the two data collection methods according to the Mann- Whitney test. So both samples were considered as a single data set.
All consumption data values were converted into hectares by dividing from the national yield. The resultant hectare values were converted into global hectares (gha) by multiplying the yield factors and equivalence factors for each criterion.
The estimated footprint per person for cropland for food items is 0.21 gha and 0.15 gha for carbon uptake lands. The forest land Ecological Footprint is 0.01 gha and footprint for built up land is 3.07 × 10 -4. The total Ecological Footprint value for all categories is 0.37 gha per person.
According to the results of the multiple regressions analysis total Ecological Footprint has positive relationship with the income, age and the education level of the decision maker in the household. There is negative relationship with the number of members in the household.
The figures of Ecological Footprint are rather low compared to the estimates available worldwide. However, the estimates are for a rural area with low resource consumption and estimates for more urban areas would be necessary to provide an indication of the overall trend of resource consumption of the country.
W.D. Sepalika and U.A.D.P. Gunawardena
Department of Forestry and Environmental Science, University of Sri Jayewardenepura Sri Lanka
Topics: Economics, Resource Management, Social aspects, sympoisum 2009 | No Comments »
Bioremediation of carbofuran by isolated bacteria from soil
By lakmali | February 5, 2010
L.M.A.M. Thilakarathne, P.M. Manage and J.A. Liyanage
Among available pesticides, carbofuran is widely used as a pesticide in all parts of Sri Lanka to improve the quality and yield of food crops by protecting against pests. Lack of knowledge on the fate and behaviour of pesticides in the Sri Lankan environment has contributed to public perceptions, fueled by local media about increasing adverse health effects due to exposure to pesticides.
In the present study laboratory experiments were conducted to isolate carbofuran degradable bacteria in soil samples collected from cultivation land in Medirigiriya where carbofuran is used as a major pesticide for agriculture. Seventeen bacteria strains were isolated from soil enrichment experiments by pour plate method. Tentative identifications were done using morphological and chemical analysis and it was confirmed that all bacteria isolates belong to gram negative and rod shape. Out of twelve, three isolates namely BC–3, BC–12 and BC–15 were selected for degradation study based on their morphological differences. Others were kept on agar slant and degradability of carbofuran by bacteria was detected by GC analysis. The bacteria isolates BC–3 and BC–12 showed a significant degradability of carbofuran, while the isolate BC–15 bacteria did not. BC–3 isolate removed 50% (±2) of the carbofuran thirteen days after incubation at 37°C (± 2) when the concentrations of pesticide were at 0.3 ppm and 0.5 ppm. The bacterial strain BC–15 showed a slow rate of degradation of carbofuran when compared with the BC–3 and BC–12 strains. In BC–15 inoculated experiment, residual carbofuran was detected even after three weeks of incubation. BC–3 bacteria showed a half life of thirteen days for 0.3 ppm and 0.5 ppm concentrations. In all bacteria strains showed high half life when concentration of carbofuran was 0.1 ppm. In contrast, variation in half life values were detected for the three different concentrations of carbofuran for BC–12 bacteria.
The results of the present study suggest that some bacterial strains in soil play an important role in biodegradation of carbofuran along with other photochemical and hydrological reactions. Further studies are being conducted to ascertain the potential impact of bacterial isolates on carbofuran.
L.M.A.M. Thilakarathne1, P.M. Manage1 and J.A. Liyanage2
1Department of Zoology, University of Sri Jayewardenepura, Sri Lanka 2 Department of Chemistry, University of Kelaniya, Sri Lanka.
Topics: Pollution control, sympoisum 2009 | No Comments »
Microstrainer for removal of algae in drinking water treatment
By lakmali | February 5, 2010
S.S. Sethunge, P.M. Manage and S. Jayasinghe
The algal management procedure, which is most actively investigated, is based on the reduction of nutrient loading which reduces algal bio mass. This is a difficult task as it requires a consensus of the community. Thus, some physical, chemical and biological control methods are being practiced to control algae. Among the available algal control methods, microstrainer is one of the cost effective physical control methods which has been developed to remove algae before water passes through the conventional water treatment processes. Microstrainer consists of a finely woven stainless wire cloth (25-35ìm) mounted on a revolving drum which has a rotation speed of 315 rpm during the operation. Very fine suspended matter such as algae and plankton can be trapped on the screen and washed away by highpressure water jets for disposal.
In Sri Lanka, currently, Only one microstrainer is being used in Polonnaruwa water treatment plant to remove algae from raw water before the treatment process. Present study was carried out to study removal rate of algae through microstrainer as no studies have been done so far in this regard. Two field experiments were carried out during June and October period based on literature of phytoplankton species composition variation of the Parakrama Samudra reservoir where water is collected to the treatment plant. Water samples were collected from different zones namely raw water where before the microstrainer, immediately after microstrainer, algae washed water from the microstrainer and filtered water. 100 ml of portion of samples were fixed with acidified Lugol’s solution at final concentration of 1% by natural sedimentation and enumeration was done under the microscopy.
Microsystis aeruginosa was the dominant phytoplankton while Pediastrum sp and Nodularia sp were co-dominates during June and October respectively. Removal rate of M.aeruginosa, through the microstrainer was 94% in June and 85% in October sampling time. In June Pediastrum duplex, Pediastrum simplex, and Scenedesmus sp removal rates were 88%, 82%, and 87% respectively and in October Nodularia sp, P.duplex, P.simplex (meyen) and Scenedesmus sp were 70%,99%,58% and 99% respectively. Merismopodia sp, Pseudotetraedron sp and Peridinium sp were recorded in water collected immediately after microstrainer and filtered water. Analysis of algae washed water samples revealed more than 90% of algae in raw water removed through the microstrainer.Thus, present study showed that the microstrainer is an efficient, cost effective and environment friendly method to remove algaem from raw water before conventional treatment processes. This may effectively reduce the cost for back wash processes and treatments of algae during the treatment processes. Therefor further studies regarding, operational efficiency and cost effectiveness should be carried out to ascertain the potential use of microstrainer for removal of algae in water treatment processes as providing safe drinking water is a global challenge in the near future due to production of algal biomass in reservoirs.
S.S. Sethunge1,P.M. Manage1 and S. Jayasinghe2
1Department of Zoology,University of Sri Jayewardenepura, Sri Lanka
2Research & Development Section, National Water Supply and Drainage
Board, Sri Lanka.
Topics: Pollution control, sympoisum 2009 | No Comments »
Managing waste in a watershed: The case of the Paradeke Oya watershed
By lakmali | February 5, 2010
K. Melvani
In 2007, areas within the Paradeke Oya watershed were impacted by an outbreak of Hepatitis A caused by the poor health and sanitation conditions in the watershed. In order to examine the underlying causes of the spread of this disease, the National Water Supply and Drainage Board contracted the Neo Synthesis Research Centre to initiate a comprehensive study.
Part of this study involved an assessment of the riparian zone of the Paradeke Oya since riparian zones are potentially valuable indicators of watershed condition. The study used the methodology espoused by a modified version of the Tropical Rapid Appraisal of Riparian Condition (TRARC) that is a visual assessment of the riparian zone using simple indicators of condition. The main areas of assessment were carried out on Plant cover, Erosion, Flow regime and Pressure; the last area of assessment includes the entry of feacal matter, solid waste, Chemical Fertilizer, Chemical Pesticides. It also included the occurrence of illegal construction, the proximity of toilets, damage from man made fire, animal grazing and other phenomena like bathing, washing clothes etc.
The data generated revealed that the waste generated from the Paradeke Oya watershed took many forms. Sewage, grey water and solid waste were a problem in both the urban and rural sectors. However the most significant source of contamination came from the use of chemical fertilizers and pesticides.
The degradation of the natural forest and riparian ecosystems combined with the lack of sanitation both in the estate and urban areas has had a debilitating impact on stream water quality. The absence of controls for the use of agrochemicals in environmentally sensitive areas is a major problem.
The most effective way to reduce the pollution load is to decrease pollution at the origin. Hence, corrective actions need to include the introduction of effective solid waste management through separation and recycling. The management of sewage through the biogas toilets for the estate line communities offers a viable option that requires changes in community practices. Centralized sewage collection and the construction of an anaerobic digester by the National Water Supply and Drainage Board could afford the opportunity for energy generation for Pussellawa town. The options are many; but what is critical is the adoption of a watershed management perspective in the planning and implementation of the restoration process. The monitoring of such programmes must use economic, social and ecological indicators of success.
K. Melvani
Neo Synthesis Research Centre, Sri Lanka.
Topics: Pollution control, sympoisum 2009 | No Comments »
Changing socio economic pattern and conservation of Maduganga wetland
By lakmali | February 5, 2010
P. Manusinghe
Maduganga situated in the Galle District of the Southern Province is typical of the river systems which line the south west coast of Sri Lanka. In the global context the ecological significance of the system has enabled it to achieve the “Ramsar Wetland” status in 2003. In the local context it is a Sanctuary, a Tourist Development Area and a Special Area Managed (SAM) by the Coast Conservation Department. The present study was motivated by the unique environment of this river system and the close relation of the inhabitants with the environment. Man’s utilization of nature and landscape over time is quite obvious in this system. The history of the man and environment relationship of the region is revealed by the historic and literary sources. Archaeological remains which belong to the recent past shed light on the constant change of local socio economics. Thus the evolution of the socio economic pattern of the research area was studied from the historical and archaeological evidence. The current state of the conditions was recognized through the participant observation and interviews with a sample of the residents in the locality.
Maduganga System represents the typical situation of the south western Sri Lanka which became the centre of power and socio economic activities from the 13th century A. D. In the Early Historic Age Maduganga region as well as the most of the south west coast had been low lying wetlands with hostile conditions for the human settlements. In 11th - 12th century A. D. southern Sri Lanka became a battlefield where the kings, princes and other leaders fought for the throne. Some of them changed the hard environment of the region to facilitate settlements and cultivation. Dambadeniya Kingdom became the first influential centre of power in the south west in the 13th century A. D. Historic chronicles reveal that Minister Dewapathiraja of the King Parakramabahu II of Dambadeniya Era had resided in the suburbs of Maduganga and developed the roads, bridges and agriculture of the area. Due to the occurrence of lagoons along the south west coast the global scenario of rising marine trade penetrated and overwhelmed the coasts. Therefore in this period ports and trade developed in the estuarine river mouths of the region while the variety of commercial and subsistant cultivations dispersed inland. This was a very critical transitional period of the socio economical pattern. With the foreign trade Cinnamon zeylanicum which grew naturally in the upper reaches of the rivers in this part of the country became a commercial crop. It attracted foreign invaders and played a pivotal role over the administration and socio economics of the region for few centuries.
Cinnamon centred economy went through major changes under the British occupation to bring out new economic values. As a result current socio economic background of the Maduganga region is dominated by tourism and fisheries. Cinnamon cultivation has also risen back after the years of collapse. These socio economic factors are very influential over the biodiversity of Maduganga wetland which is amply populated today. From this population our sample was ten households of the Maduwa Island. The main living of the majority of these was government and private sector employments which consecutively form 40% and 20% of the total. The rest is consisted with fisheries 20%, trade 10% and agriculture 10%. Therefore the principal income of only the 30% of the households is connected with the environment. But all the households have one or more secondary incomes as cinnamon cultivation, coir industry and tourism which directly involve environment. It clearly depicts the trend towards engaging in the formal employments extract of the environment while making an informal living from their environment. The research revealed the pros and cons of this current socio economic background of the region and the most appropriate conservation and management measures. Some practices of eco tourism, such as encouraging residents and tourists in enriching the mangroves are an example.
P. Manusinghe Department of Archaeology, University of Kelaniya, Sri Lanka.
Topics: Resource Management, Social aspects, sympoisum 2009 | 1 Comment »
Ensuring human safety and addressing environmental concern through better
By lakmali | February 5, 2010
K. Khobragade
The waste, which is generated during the diagnosis, treatment or immunization of human beings or animals, in search activities pertaining humans or animals or in the production or testing of biologicals is called Biomedical Waste (BMW). The main and exact reason of bio-medical waste as a problem was in its poor management. In India, only a few states and districts have given adequate thoughts to manage the collection and disposal of BMW properly.
Keeping in view the inappropriate bio medical waste management, the Ministry of Environment andForests notified the ‘Biomedical Waste Management and Handling Rules 1998’ in July 1998 (Later amended on 2nd June, 2000). The soul principle of this rule was to carry out segregation, collection, transportation and disposal of the mentioned above by maintaining hygienic conditions throughout the arena.
The study had been carried out between the periods of June 2007 to May 2008. Accordingly, the population of Aurangabad city was 10.99 Lakhs as per 2001 census. This city had been recorded as the fastest growing industrial township in the Asian subcontinent. BMW treatment plant of AMC had been implemented since 1st Nov.2003 in Gevrai Tanda, Patoda shiwar area near Aurangabad and this contract has been made with Water-grace products, Biomedical Waste Management, Nasik on BOLT (Build Operate Lease Transfer) on the basis for 20 years. Amongst the Autoclave, Hydroclave, Microwave, Incinerator and Chemical technology; the concern agency adopted Incinerator technology.
All government, semi-government, private, NGO’s or the people who generated BMW were the members of this mentioned project. There were 662 members upto the date of 1st March, 2008. The data had been collected through means of official documentation by AMC, questionnaires filled by doctors, personal interviews, field-visits to the treatment plants, and the parallel pilot projects. The findings were as follows:
1) The response given by the doctors was considerably appreciable but there was no watch on illegalpractitioners. So, AMC should have driven a special action against it.
2) There was a need to provide a technical training to the workers engaged in this system as they wereexposed to deadly infectious diseases generating through it.
3) The heat released through Incineration process should have been trapped and utilized further.
4) The remaining of BMW could have been used as manure. In pilot experiment, this manure enhancesthe growth of plants.
5) The Audit of BMW was required to understand the quality and quantity of the waste generated.
6) There was a need to improve the machine-technology in an Incinerator process on it so as torelease the visible smoke.
7) Disposal facility was only one of the links in the Bio Medical Waste management chain. Therewere other key-links that were required :
· Education and Awareness.
· Compliance monitoring and accountability.
· Regulatory system and tools.
In the developing countries, due to lack of costly, sophisticated machinery, the concerned authoritiesshould focus on 3 R’s (Reduce, Reuse, and Recycle) and through scientific eco-friendly techniques, methods should be implemented so as to sustain a healthy environment ensuring betterment in health of every citizen.
K. Khobragade
S.B.E.S. College of Science, Aurangabad, India
Topics: Pollution control, sympoisum 2009 | No Comments »
Utilization of molluscs as a food resource among traditional communities in Kalpitiya Region (KR) of Sri Lanka
By lakmali | February 2, 2010
T. Siriwardana
The present ethnography of fishing communities can be divided as; Deep sea fishing and Littoral - lagoonal fishing. Over the recent decades, the number of coastal zone users increased considerably and so has the nature of demands. The latter include the exploitation of resources found in the zone. Studying current uses of marine and brackish water mollusc resource has two prime values. First is, as it is depicting the periods in history and changes of the shell utilizing pattern. The second is recording recent trends for future studies. Currently the shell resource is drastically running out due to escalating use. Therefore research on fishing culture and utilization of molluscs is important to the future archaeomalacological studies, which is largely untouched by the Sri Lankan researchers. Present research partially fills this void by examining the exploitation of marine and brackish water gastropod and bivalve molluscs in archaeological and ethnographical contexts for the better understanding of the relation between man and molluscs. The research is focused on traditional cultural-economical uses, specially the food economy.
From the edible marine organisms, molluscs fill a considerable amount of sea food consumed by man. Two major classes of them, i.e. bivalves and gastropods are utilized to meet this demand. One main locality was examined here, i.e. Kalpitiya Ânavâsala (KA) in North West coast of Sri Lanka. Shell samples were collected from the kitchen middens in the selected region, participant observation and interviews were made with locals. Total shell sample was measured and recorded. Results.
Thirteen main edible species were identified from the kitchen middens of KA. From them three types can be found largely in the middens, i.e. Pugilina cochlidium, Paphia sp., Gafrarium tumidum. The other species are very scarce in the middens, but that does not indicate their dietary importance is minor. The main point is that the gatherers collect all species which they know as edible. The said
abundant species are higher in total biomass and easy to collect. Except Turbinella pyrum, Murex ramosas and Lambis chiragra, others are collected mainly from their usual habitats such as sandy bottoms, intertidal flats, subtidal flats and on muddy sand flats seaward from mangrove forests. The rate of the utilization pattern, when it was analyzed with the composition of kitchen middens of the studying area ca. 70% of kitchen middens are comprised with the shells of bivalves (9 middens) and ca. 30% (4 middens) with gastropod shells. In the west coast mollusc collecting is started in April and prevails for six months, which is the active period of high sea (vârakan) of south west monsoon. In the diet of the locals shell fish play many roles as a staple food, subsidiary foods, snacks, and an alternative food source when other subsistence strategies fail. Traditionally maritime communities have their own
terminology not only for the various species but also for collecting, shucking and cooking methods.
Utilization of marine and brackish water molluscs in certain traditional maritime cultures is a vertical process of cultural transmission (generational transmission through time). The horizontal process or the cultural exchange across space can be seen through history and society. Hence the use of marine molluscs as a food resource is significant in socio - economic studies of both archaeological and
environmental approaches.
T. Siriwardana
Department of Archaeology, University of Kelaniya, Sri Lanka.
Topics: Economics, Resource Management, sympoisum 2009 | No Comments »
Economic value of mangrove ecosystems in the Panama village, Ampara district:a case study
By lakmali | February 2, 2010
K. Wijayaweera1, S.P.N. Perera2 and V.A.P. Samarawickrama3
Sri Lanka encompasses a high diversity of coastal vegetation, specifically mangroves and these ecosystems have provided a wide array of goods and services, ranging from fishery, forest products and tourism to shoreline protection. The need to assess the economic value of mangroves became more eminent to assist policy-makers and funding agencies in integrating mangrove restoration activities in environmental conservation programs. The study was initiated to estimate the direct and indirect values of mangrove ecosystems and the protection role played at extreme disastrous events such as Tsunami to the coastal communities in Ampara District of Sri Lanka. Information on eco-physical and socioeconomic including various damage costs and dependency on mangrove ecosystems was collected using purposive sampling from 109 households from Panama village which was characterized with well managed and functioning coastal ecosystems where mangroves were relatively intact. The shoreline protection value was assessed by comparing the Panama village with 100 coastal households from villages in Potuvil town where mangrove ecosystem was comparatively degraded due to tsunami. The results revealed a higher mangrove dependence of the Panama villagers with a value of Rs.119, 438/household/year (US$1,171). It was also revealed that estimated incidence of damage costs in areas with degraded mangrove vegetation was significantly greater during the tsunami. The costs of damages to livelihood and property in Potuvil (US$ 13,509) were approximately twenty times the costs of damages in Panama (US$ 623). Field observation also revealed massive destruction to the coastal ecosystem (property and vegetation damages and sea erosion) in Potuvil compared to Panama. Results clearly indicated that areas with intact mangrove ecosystem generate greater economic benefits. The findings also indicate the economic rationale of including mangrove restoration efforts in the environmental conservation programs.
K. Wijayaweera1, S.P.N. Perera2 and V.A.P. Samarawickrama3
1Post Graduate Institute of Agriculture, University of Peradeniya, Sri Lanka
2Department of Crop Science, University of Peradeniya, Sri Lanka
3Department of Zoology, The Open University of Sri Lanka.
Topics: Economics, Resource Management, sympoisum 2009 | No Comments »
Socio-economic factors affecting the technology adoption level of sugarcane in rainfed sector in Sevenagala
By lakmali | February 2, 2010
T.D.G.J. Peiris, N.R.Abeynayake and M.S. Perera
Sugarcane (Saccharum spp) is an important commercial crop cultivated in Sri Lanka over an area of 18,500 hectors. At present domestic sugar production is 56,000 tones per annum, which was sufficient to meet only 9% of the local requirement. The national average yield is 55 tones per hectare. The potential yield is more than two times of that. Non adoption of the technologies was considered as the one of the major reasons for this yield gap. Thus the objective of this study was to find out the technology adaptive level and the socio-economic factors which affect the technology adoption level. The study was conducted in rainfed sector in Sevenagala sugar industry from April to May in 2009. The farmer survey was conducted with 50 farmers which cover a population of approximately 1000 farmers in 3 divisions. Recommended Technology Adoption Index (RTAI) was developed using the scores obtained from the extension officers for twenty two technologies according to the contribution for increment of yield and adoption level of farms using five rating point likert scale (strongly adopt, adopt, poor adopt, very poor adopt, and not adopt). RATI can be used as an indicator of technology adoption levels of each farmer. The correlation between RTAI and yield was 62.26%. Average technology adoption index of study area was 0.7213 with minimum 0.46 and maximum of 0.89. Empirical model was developed to see the relationship between the recommended technology adoption and ten independent variables namely age, monthly income, education, experience, family labour involvement, farmers’ visit of extension office, member of social association, farmer group meetings, frequency of field visit of extension officer, information obtained through the leaflet. Ordered Logistic Regression technique was used to estimate the coefficient of the model, to which four levels for the dependent variables was derived using the range of values of the RTAI. The results revealed that the adoption of recommended technologies was significantly influenced by the monthly income, being a member of social association and farmers’ visit of extension office. Increment of access for loans and strengthening the extension service is suggested to enhance the technology adoption level of sugarcane cultivation.
T.D.G.J. Peiris, N.R.Abeynayake and M.S. Perera
Wayamba University of Sri Lanka.
Topics: Economics, Resource Management, sympoisum 2009 | No Comments »
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
By lakmali | February 2, 2010
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.
Topics: Economics, Forest Management, Plantations, sympoisum 2009 | No Comments »