105 research outputs found
ESTIMATION OF EXISTENCE VALUES SOME EMPIRICAL ISSUES
Existence values (EVs) are the values derived from the knowledge that certain species ornatural environments exist. Existence values arc pure public goods and hence lack marketvalues. As income rise and natural environment suffer greater degradation, demand forexistence values is likely to increase. This paper presents results of a contingent valuationsurvey designed to elicit existence values of a tropical rain forest and several issues relatedto estimation of existence values of a global resource.A contingent valuation survey was carried out in order to derive EVs for the Sinharaja RainForest Reserve in Sri Lanka. An open ended question format was used with a neutral trustfund as a payment vehicle. Three samples from Sri Lanka (urban and rural areas distant tothe forest and peripheral villages to the forest) and one remote sample (from UK) were usedin the study. The existence values for different types of users such as educational users.recreational users and non users were derived from the survey.When expressed as percentage of income, willingness to pay values showed cleardifferences among different user types in different samples. On average, local ruraleducational users stated the highest values while remote non-users stated the lowest values.These existence value estimates, notwithstanding the theoretical validity, clearly illustratethe empirical problems related to estimation of existence values.It could be assumed that existence values stated by non-users provide the nearestapproximation for the 'true' existence value of a resource. However, this relates with theprovision of information and the knowledge of the respondent since people derive benefitsdirectly and indirectly and they may be aware or unaware of such benefits emanating fromtropical rain forests.Implications of these findings in designing future existence value estimations and the role ofinformation in survey design are highlighted. Implications for policy at global level,specifically, how mechanisms for appropriation of such values could be developed are alsodiscussed.
ECOLOGICAL ECONOMICS: A BETTER FRAMEWORK FOR SUSTAINABLE DEVELOPMENT
Sustainable development has been the focus and. the target of many resource managementrelated issues. However, proper definitions and frameworks of action have seemed to begreatly unexplored. This paper aims at providing a framework for sustainable developmentbased on concepts of ecological economics. The main focus will be on the issues of intraand inter generational equity on natural resource use and maintaining non-declining levelsof critical natural capital.The conventional economic view is generally optimistic about the ability of the economicsystem to overcome natural resource depletion with the help of the technological progress.However, conventional approaches in resource economics limit themselves to only optimalrate of exploitation of a natural resource and determination of optimal pollution discharges.Although such approaches are sensitive to scale issues at the micro level, it is insensitive tothe macro level scale of the whole economy relative to the ecosystem. Although the marketprovides space for substituting abundant resources for scarce ones, it is not able toovercome entropy constraints. Such issues are not reflected in Pareto optimality sinceoptimal allocation is independent of whether or not the scale of physical throughput isecologically sustainable.Therefore is important to recognize the existence of a new constraint on the physical scaleof the economy relative to the ecosystem. This constraint has to be set according to thecriteria of sustainability and under such constraint, the market will be able to achieveprices which reflect the social value of sustainability.Unique natural environments and other critical natural capital need special considerationsin economic analysis since technology can do little to replicate their ecological, physicaland geographical characteristics. In order to determine the social cost and benefits of adecision to develop a previously undeveloped area, it is necessary to know both thepreferences of present and future generations who may be affected by that decision. Theexisting valuation frameworks and discounting in cost benefit analysis have inherent biasesagainst future generations. Recognition of such facts and identifying the means ofminimizing such biases are essential in achieving sustainable development.Ecological economic framework is essentially an extension of environment and resourceeconomics in to the explicit analysis of biophysical constraints and equity amonggenerations.
GLASS RECYCLING IN SRI LANKA: A FINANCIAL ANALYSIS
Glass recycling is the use of secondary raw materials or post consumer glass waste for the manufacturing of new or similar products. Glass Company of Sri Lanka is manufacturing glass containers and also involved in glass container recycling in Sri Lanka. The main purpose of the study is to carry out a financial analysis of glass recycling from company point of view along with an analysis on possible best practices that could enhance the recycling behaviours of individuals. The primary data was gathered from a household questionnaire survey which was conducted in Western Province of Sri Lanka. Sample of 150 households were selected from 8 GN divisions in  Colombo, Gampaha and Kaluthara districts representing two Municipal councils, three urban councils, and three Pradeshiya Sabha. Six different scenarios were proposed for the respondents in order to generate information on practices that are most preferred by them and on their willing levels of recycling under each scenario. Results revealed that the best scenario was the introduction of door to door collectors which yielded highest net present value of Rs. Mn 1,517.39 at 10% discount rate and resulted 7.98% of net profit increase from the current glass recycling process of Glass Company
EVALUATION OF URBAN AIR POLLUTION COST A CASE STUDY IN THE COLOMBO CITY
Air pollution is arguably the most important. in terms of economics cost, of thevarious types of pollution caused by transport and industrial activities and itseffects have been widely studied in other countries. However, direct studies havenot been undertaken to measure the economics cost of air pollution in Sri Lanka.Concern for air pollution in Sri Lanka is focused mainly in Colombo. AlthoughColombo air pollution level is less than many Asian countries, recent monitoringresults show that air pollution from particulate matter and Sulfur is well above theWHO recommended levelThe contingent valuation method was used to estimate the air pollution cost anddata was collected from a contingent valuation survey carried out in the Fort andPettah areas. Respondents' willingness to pay values were obtained for ahypothetical market presented. The results were consistent with the economictheory. Aggregated cost of air pollution for the country was Rs.55 million peryear. This value may help cost benefit analysis of air quality managementprogrammes and other related development policy and programs in Sri Lanka.
EXTENDED COST BENEFIT ANALYSIS OF SAMANALAWEWA HYDRO ELECTRIC PROJECT
The Samanalawewa Hydro Electric Project and its water commanding area is the subject ofthis study. This project is a single purpose hydropower project, which harnesses the watersof the Walawe Ganga by damming the river at the confluence of the Belihul Oya andWalawe Ganga at an elevation of 400m Mean Sea Level. The reservoir covers an extent of897 ha at normal high water level and its catchment covers an area of 341.7 km".As this was a single purpose project, much attention was not paid to other aspects such assupplying irrigation water for down stream and other environmental impacts. Thereforethis study sought to estimate the economic loss due to the reduction of land area and paddyyield at selected down stream areas. In addition, it aims to estimate the economic value oflost carbon sequestration function of the Samanalawewa reservoir submerged area and toincorporate the above values in an extended Cost/Benefit analysis for the Samanalawewaproject.Primary and secondary data were used for this study, which involved a farm householdsurvey. This research disclosed that the scarcity of water due to the dam has resulted in11.64% of yield reduction (equivalent to 36<;44.38 bushels or Rs. 10.5 million) and 24.89%of land become uncultivated (equivalent to 444.27 acres or RS.II. 7 million) annually. Theglobal warming damage costs due to .he lost carbon sequestration function of thesubmerged area is estimated to be Rs. 0.22 million annually. The estimated economic valueof surplus water in terms of foregone powe. generation from the leak at paddy harvestingperiods (April, September and October) is Rs. 95.33 million.The extended cost benefit Analysis showed that EIRR equals 6 %, NPY equals Rs. (-)1980.23 million, and BC Ratio equals 0 47. The implications of these results on futurepower-sector project planning are also discussed.
EXTENDED COST BENEFIT ANALYSIS OF A BIOGAS GENERATION PLANT
Solid waste is a growing problem in Sri Lanka in the absence of proper managementmeasures. Development and implementation of a National strategy for municipal solidwaste management is essential in order to reduce environmental, social and the economicproblems associated with the present disposal practices. Such strategies however, need tobe subjected to proper economic analysis in order to arrive at informed decisions. Thispaper presents an extended cost benefit analysis of a biogas generation plant that usesmunicipal solid waste as the raw material.To dispose vegetable market garbage available in Wattala, Kandana and Ja-ela areas a640 Mt capacity biogas/ bio fertilizer project has been housed at Muthurajawela (alongHamilton canal, Elakanda), by the National Engineering Research & DevelopmentCenter of Sri Lanka (NERDC) which uses Dry Batch Anaerobic Digester Technology.Among the other biological treatment options, anaerobic digestion is the most costeffective, due to the high-energy recovery linked to the process and its limitedenvironmental impacts.Economic analysis has been carried out to identify environmental costs and benefitsassociated with the above project. Several environmental valuation methods have beenapplied to value the identified costs and benefits. The main benefit of reduction ofmunicipal solid waste has been estimated by contingent valuation method using samplesfrom Wattala-Mabola, Ja-ela, and Peliyagoda local authority areas. Another benefit is thereduction of green house has emission due to the reduction of open dumping. Greenhouse gas (methane) emission from solid waste was estimated through Sholl Canionmodel and valued using avoided global damage cost approach. Benefits of biogas asenergy and organic fertilizers and employment benefits were estimated by market basedapproachesThe project is viable from economy and environment point of view with net present valueof Rs 142 million for a 20-year period with 10% discount rate. This analysis provides ajustification for undertaking solid waste management strategies in a technologically,environmentally and economically viable manner
Economics of urban amenities A contingent valuation approach for Bolgoda lake
Bolgoda Lake is known as the largest fresh water body in Colombo Urban Area (CUA) and situatedin the Southern boundary ofCUA. It covers 1,245 hectares. There are 14 Divisional secretariat (OS)divisions and 105 Grama Niladary (GN) divisions. Bolgoda Lake lies along the highly popularizedtownships and it provides a variety of environmental services such as natural environment for fisheriesproduction and estuary function; ground water recharge, potable water supply; recreation/ tourism;and )1atural biotic habitat. In CUA, there are very few lakes like Bolgoda, which provides aestheticvalues for the urban environment. Environment of the Bolgoda Lake is threatened by the disposal ofliquid and solid waste, agricultural run-off, sedimentation and congestion due to recreational uses.However, there wi II be an increasing demand for the environmental services produced by the BolgodaLake in the future.Objectives of the present study are to identify the environmental benefits of the Lake and estimateeconomic value of selected environmental benefits. A pilot survey was carried out and five major usergroups were identified; fishermen, hotel owners, boat owners, recreational users (for swimming andhotel visiting) and indirect users. Selected study area for the present study belongs to five GN divisionsfrom Moratuwa and Panadura OS divisions. Contingent valuation method was applied to estimate theeconomic value of the Bolgoda Lake. Users' willingness to pay (WTP) was elicited on a pre-testedhypothetical market.Depending on the WTP values, the 5 user groups were regrouped into two categories, namely User I(heavy dependency) and User 1/ (less dependency). WTP values per household per year for the UserI and User II are Rs.18, 600 and 514.3 respectively. Estimated economic value of the Bolgoda Lakefor the study area is Rs. 84,192.7 (US$ 809.55) per hectare per year. Regression analysis was carriedout to identify the socio economic characteristics of the users that affect the WTP value of the users.The results were consistent with the theory. However, the values of the study area have not beenextrapolated to the whole lake, due to the high variability of the sample mean from place to place.It was clear that the Bolgoda Lake is a valuable aesthetic asset in the CUA and it should be judiciouslymanaged for sustain the provision of environmental services. However, the ultimate decision over theusefulness of the lake has to be based on weighing the estimated value of the environmental servicesof the Lake against the value of the use of lake as a sink for domestic and industrial waste.
DEVELOPMENT OF AN ECO~BUSINESS DIRECTORY: APPROACHES AND CHALLENGES
Eco-business is the provision of products and services that are environmentally friendly.When the preferences of the society are heading towards environmental safety, ,manufacturers need to adjust their production and marketing strategies to respond to thischange in consumer preferences. Eco-business aims at exploiting the market mechanismto provide the market with more environmentally responsible products. This studypresents the approaches used and challenges faced in the development of an eeo businessdirectory for Sri LankaThe building of the preliminary model for an eco business directory was done with thehelp of five types of surveys. Firstly, an island-wide industrial survey has been carried outwhich included major industries, hotel industry and minor industries. Secondly, an expertopinion survey was carried out to review the existing situation on a sectoral basisregarding eco-friendly products/services and to explore the possibilities and recentdevelopments of new products and services. Thirdly, a survey of existing literature wasdone in order to understand experiences regarding eco-friendly products in differentcontexts. In addition, NGO activities related environment has been collected in order toidentify gaps in public participation. In addition, available financial mechanisms for ecoindustries have also been listed.The main challenges faced in the preparation was the limited response from the relevantparties for the surveys. The lack of awareness on the 'eco friendly' products and serviceswas another issue which need further theoretical and practical definitionsIf eco ousinesses are to be establisued as a complete business s.rategy, environmentalclaims had to be accurate and independently substantiated. It is not likely that marketplace would resolve these problems on its own. The paper elaborates on the need ofguidelines and specifications on eco friendly products and services.
Assessment on timber and carbon in rubber plantations with special reference to the wet zone of Sri Lanka
Rubber (Hevea brasilensiss has traditionally been cultivated for the latex extraction; however, itsimportance in other uses, particularly producing quality timber and sequestering atmospheric carbonas a permanent sink, is also often highlighted. The amount of timber produced and carbon sequesteredin rubber trees has been assessed in isolations. Those values would differ under different growthconditions and to date, no simple protocol is available to quantify the amount of timber and carbon inrubber plantations. Therefore, the study reported here was aimed to develop simple growth models toassess the timber production and carbon fixing capability of rubber plantations in Sri Lanka.Initially, a growth function was developed to assess the girth development with respect to age andthereafter another three functions to quantify the amount of timber, biomass and carbon in the rubbertree based on girth diameter. Also, wood density variation with age of the tree was modeled todetermine the biomass in timber under different age categories. The assessment on the availablecarbon was based on the carbon content in unit biomass and the total amount of biomass in the tree.Growth data required for the girth development function were gathered from secondary sources andgirth measurements made on existing rubber clearings. Destructive sampling was conducted to assessthe timber, biomass and wood density.Based on above models, an average rubber tree at 30 years achieves a girth of 88.64 ern and produces0.656 m' of timber and 594.46 kg of biomass. The amount of atmospheric carbon fixed in timber atthis age was estimated as 193.7 kg per tree and 45.86 MT per hectare. However, total amount oforganic carbon fixed in above ground components was 220.8 kg per tree and 52.27 MT per hectare.The models of this study were developed under general conditions in the wet zone, hence should bevalidated for drier regions of the country before any wide scale adoption.
In silico evolution of signaling networks using rule-based models: bistable response dynamics
One of the ultimate goals in biology is to understand the design principles
of biological systems. Such principles, if they exist, can help us better
understand complex, natural biological systems and guide the engineering of de
novo ones. Towards deciphering design principles, in silico evolution of
biological systems with proper abstraction is a promising approach. Here, we
demonstrate the application of in silico evolution combined with rule-based
modelling for exploring design principles of cellular signaling networks. This
application is based on a computational platform, called BioJazz, which allows
in silico evolution of signaling networks with unbounded complexity. We provide
a detailed introduction to BioJazz architecture and implementation and describe
how it can be used to evolve and/or design signaling networks with defined
dynamics. For the latter, we evolve signaling networks with switch-like
response dynamics and demonstrate how BioJazz can result in new biological
insights on network structures that can endow bistable response dynamics. This
example also demonstrated both the power of BioJazz in evolving and designing
signaling networks and its limitations at the current stage of development.Comment: 24 pages, 7 figure
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