Agriculture, Food, Environment, and Sustainability
The Official Research Journal of the Institute of Sustainable Agricultural, Food, and Environmental Sciences
The Official Research Journal of the Institute of Sustainable Agricultural, Food, and Environmental Sciences
Publications in 2020
Data Deficiencies on Abandoned Lost and Discarded Fishing Gear and Fishing Gear Waste in Sri Lanka and Their Implications for Decision Making.
Article by W. R. W. M. A. P. Weerakoon, H. B. U. G. M. Wimalasiri, P. M. N. Mihirani, and J. P. U. Samaraweera (2020)
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W. R. W. M. A. P. Weerakoon1, H. B. U. G. M. Wimalasiri1, P. M. N. Mihirani2, and J. P. U. Samaraweera3
1InstituteNational Aquatic Resources Research and Development Agency, Sri Lanka.
2Institute of Sustainable Agricultural, Food, and Environmental Sciences, Sri Lanka.
2Institute of Tropical Marine Sciences, Sri Lanka.
Comprehensive and systematically collected data on the extent, causes, and management of abandoned lost and discarded fishing gear and fishing gear waste in Sri Lanka remain limited across marine, coastal, and inland fisheries. Although isolated studies and pilot surveys provide preliminary insight into gear loss among segments of the marine fleet, there is no nationally representative baseline, no repeatable monitoring framework, and no integrated reporting mechanism that captures spatial distribution, gear specific loss rates, inland fisheries inclusion, or ecological and socioeconomic consequences. This review critically examines the structural nature of these data deficiencies and demonstrates how they constrain risk assessment, regulatory prioritization, institutional coordination, and performance evaluation. The absence of standardized quantification and centralized data integration prevents evidence based decision making and limits Sri Lanka’s capacity to implement preventive and adaptive governance strategies.
1. Structural Nature of the Data Deficiency in Sri Lanka
The data problem surrounding abandoned lost and discarded fishing gear and fishing gear waste in Sri Lanka is not merely a question of limited research output. It is structural, institutional, and methodological in nature. The deficiency arises from the absence of a coherent national data architecture that integrates fisheries management, marine environmental monitoring, and waste governance systems. Information exists in fragmented and non interoperable forms, but these fragments do not collectively generate decision relevant intelligence. As a result, the governance system operates without a measurable understanding of magnitude, spatial distribution, causation pathways, or management performance.
At the institutional level, data generation is dispersed across multiple agencies whose mandates intersect but do not align operationally. The fisheries administration collects vessel registration data, catch statistics, and licensing records, yet does not systematically collect data on gear loss events or disposal practices. Environmental authorities monitor marine litter and coastal pollution through periodic beach surveys, but fishing gear is recorded as a general debris category rather than as a fisheries specific management variable. Local authorities manage solid waste streams at landing sites, yet fishing gear waste is not treated as a distinct material flow requiring tracking or documentation. This institutional compartmentalization results in data silos, where partial observations are generated but not synthesized into an integrated assessment framework.
Methodologically, existing information relies heavily on episodic surveys and self reported data rather than structured, statistically designed monitoring systems. The recent pilot survey on marine gear loss represents an important starting point, but it was not embedded within a national stratified sampling design covering all fleet segments, coastal districts, and operational scales. There is no standardized protocol for annual replication, no requirement for geospatial tagging of loss events, and no mechanism for cross validation through independent observation or retrieval documentation. Consequently, the study functions as an isolated snapshot rather than as a foundational baseline for longitudinal assessment.
A further structural limitation is the absence of definitional harmonization across agencies and programs. The terms abandoned lost and discarded fishing gear, fishing gear waste, marine debris, and plastic waste are often used interchangeably in administrative contexts without clear operational distinctions. This definitional ambiguity affects data classification and prevents consistent reporting. For example, a damaged net disposed at a landing site may be recorded under municipal solid waste statistics, while a similar net lost offshore may be absent from fisheries statistics entirely. Without harmonized definitions and reporting categories, the national dataset cannot be aggregated meaningfully.
Spatially, the structural problem manifests as uneven observational intensity. Data collection efforts tend to concentrate where monitoring is logistically simple, such as accessible beaches or selected landing sites. Offshore areas, benthic habitats, and inland reservoirs receive little or no systematic observation. This creates geographic asymmetry in data availability. Decision makers therefore rely on visible coastal indicators while submerged and inland accumulations remain unquantified. The governance system is consequently biased toward what is observable rather than what is environmentally significant.
Temporal inconsistency further compounds the structural weakness. Existing studies are episodic and project based, often linked to short term funding cycles. There is no institutionalized mechanism ensuring continuous annual data collection. Without time series data, it is impossible to detect trends, evaluate the effectiveness of policy interventions, or assess the influence of seasonal variability such as monsoon cycles. Governance decisions are therefore made without temporal context, limiting adaptive capacity.
Another core structural issue is the absence of mandatory reporting obligations within fisheries regulation. Gear loss is not recorded in logbooks, nor is there a formal requirement to notify authorities when loss occurs. In the absence of reporting requirements, the state depends entirely on voluntary disclosure or external survey initiatives. This creates systematic underreporting bias and removes the possibility of real time spatial analysis. Without compulsory reporting, the state cannot construct a national incident database or identify recurrent loss zones.
The structural deficiency also reflects a disconnect between fisheries management objectives and environmental monitoring priorities. Fisheries governance in Sri Lanka traditionally focuses on catch regulation, licensing, and effort control. Environmental governance addresses pollution broadly but does not treat fishing gear as a discrete fisheries management variable. This separation prevents the integration of ALDFG into stock assessment models, habitat protection strategies, or marine spatial planning processes. Consequently, the issue remains administratively peripheral rather than central to fisheries sustainability.
Finally, the inland fisheries sector exemplifies structural exclusion. While marine fisheries have at least been the subject of preliminary gear loss investigation, inland systems have not been incorporated into any national assessment of gear waste or loss. Reservoir fisheries operate under separate administrative arrangements, and environmental monitoring in freshwater systems rarely categorizes fishing gear as a pollutant class. The omission of inland waters from the data architecture demonstrates that the deficiency is systemic rather than sector specific.
In summary, the structural nature of Sri Lanka’s data deficiency lies in fragmented institutional mandates, absence of standardized methodologies, definitional ambiguity, uneven spatial coverage, temporal discontinuity, lack of mandatory reporting, and the separation of fisheries and environmental governance systems. These structural characteristics collectively prevent the formation of a coherent national evidence base. Without reforming this underlying architecture, additional isolated studies will continue to generate information fragments rather than enabling comprehensive, decision relevant intelligence.
2. Insufficient Quantification of Extent Across Marine, Coastal, and Inland Systems
The quantification of abandoned lost and discarded fishing gear and fishing gear waste in Sri Lanka is constrained by methodological limitations, incomplete sampling coverage, and the absence of a statistically robust national baseline. Although a recent pilot survey of marine fishers provided the first estimate of annual gear loss, the design and scope of that survey do not permit reliable extrapolation to national scale. The study relied on self reported data from a subset of vessels, without proportional stratification across fleet categories, geographic regions, or operational scales. Sri Lanka’s fisheries sector is heterogeneous, comprising multi day offshore vessels, one day mechanized boats, non mechanized craft, beach seine operations, lagoon fisheries, and reservoir based inland fisheries. Loss dynamics differ significantly across these segments due to variations in gear type, fishing grounds, depth, weather exposure, and retrieval capacity. In the absence of stratified sampling aligned with this structural diversity, reported averages cannot be assumed to represent the national fleet.
Self reporting introduces additional uncertainty. Fishers may underreport losses due to recall bias, perceived regulatory risk, or normalization of loss as routine operational cost. Conversely, overestimation may occur when damaged but recoverable gear is included in reported loss. Without independent verification through onboard observers, retrieval documentation, or port inspections, the true variance around reported loss values remains unknown. Confidence intervals were not established through probabilistic sampling design, meaning that national scaling would involve compounding uncertainty. As a result, the estimated annual mass of lost gear cannot serve as a statistically defensible baseline for trend monitoring or policy evaluation.
Spatial quantification is similarly limited. The pilot survey did not systematically georeference loss events. Without spatial coordinates, it is impossible to identify recurrent hotspots, overlap loss locations with sensitive habitats, or correlate gear loss with bathymetric features and reef systems. Marine gear loss is not spatially uniform; it is influenced by fishing intensity gradients, seabed topography, navigational routes, and conflict zones between fleets. In the absence of spatial resolution, management cannot prioritize high risk zones for retrieval, enforcement, or preventive intervention. National magnitude estimates, even if accurate in aggregate mass terms, are insufficient for spatially targeted governance.
Coastal quantification relies primarily on beach debris monitoring programs. These programs record the presence of fishing related plastics among stranded litter, but they are not designed to estimate total environmental stock. Beach surveys measure deposition at the land sea interface, not the submerged reservoir of gear entangled in reefs or resting on the seabed. Furthermore, beach accumulation reflects hydrodynamic transport processes rather than original loss locations. Wind, current, and tidal patterns redistribute debris, often concentrating it in specific embayments irrespective of where loss occurred. Consequently, beach data cannot be used to infer offshore magnitude without complex drift modeling, which has not been undertaken in Sri Lanka. The coastal dataset therefore represents a secondary signal rather than a primary quantification tool.
Benthic accumulation remains almost entirely unquantified. There are no systematic underwater surveys estimating the density of lost nets on coral reefs, rocky substrates, or trawl grounds. In many fisheries globally, a substantial proportion of lost gear sinks and remains submerged rather than washing ashore. Without diver surveys, remotely operated vehicle assessments, or sonar based mapping, Sri Lanka lacks any empirical estimate of submerged stock. This omission is critical because submerged gear is the primary driver of ghost fishing and habitat damage. The current national data architecture captures only the most visible fraction of the problem.
Inland systems represent the most significant quantitative blind spot. Reservoirs, tanks, and lagoon fisheries collectively support thousands of fishers using synthetic gillnets and lines. However, there are no datasets documenting annual loss rates in freshwater environments. Gear entangled in submerged trees, irrigation infrastructure, or spillway structures may remain undetected and unrecovered. Reservoir drawdown cycles may periodically expose accumulated nets along shorelines, yet no structured surveys have quantified these occurrences. The exclusion of inland waters from national estimates results in systemic underestimation of total gear loss and waste generation. Any national figure derived solely from marine fisheries is therefore incomplete by design.
Temporal quantification is equally deficient. Existing data derive from single year or short term assessments. There is no time series capable of distinguishing interannual variability from structural trends. Gear loss may fluctuate with monsoon intensity, fuel prices, fishing effort, regulatory changes, or technological shifts in gear materials. Without multi year datasets, policymakers cannot assess whether interventions reduce loss rates or whether environmental variability amplifies them. The absence of temporal continuity prevents adaptive management and undermines predictive modeling.
Material specific quantification is also insufficient. Sri Lanka’s fisheries utilize a mixture of nylon monofilament nets, polyethylene ropes, polypropylene lines, and composite gear components. These materials differ in buoyancy, degradation rate, and ghost fishing persistence. However, national data do not disaggregate losses by polymer type or gear construction characteristics. Without material level data, it is impossible to estimate environmental persistence or microplastic generation potential. Management strategies such as biodegradable gear promotion or material substitution cannot be evaluated without baseline material composition data.
Another critical quantitative limitation concerns stock versus flow distinction. Existing data focus primarily on annual loss flow, that is, gear lost within a specific year. There is no estimate of cumulative stock already present in marine, coastal, or inland environments from previous years. Environmental risk depends not only on new annual inputs but also on legacy accumulation. Without stock assessment, policymakers cannot determine whether the problem is compounding or stabilizing. Stock quantification would require retrospective modeling, retrieval surveys, and decay rate estimation, none of which have been conducted.
Uncertainty analysis is absent from national discourse. No sensitivity analysis has been performed to estimate how assumptions about reporting accuracy, fleet size scaling, or regional variation affect national totals. Without explicit uncertainty bounds, policy may either underestimate risk and under allocate resources or overestimate magnitude and misdirect funding. Decision making under uncertainty requires transparent quantification of error margins, yet current datasets do not provide this foundation.
In summary, quantification of ALDFG and fishing gear waste in Sri Lanka is limited by non stratified sampling, reliance on self reporting, absence of spatial georeferencing, lack of submerged and inland surveys, insufficient material disaggregation, absence of cumulative stock assessment, and lack of temporal continuity. These methodological and structural weaknesses render existing estimates indicative rather than definitive. As a result, national governance operates without a statistically defensible baseline, preventing rigorous prioritization, monitoring, and evaluation of interventions.
3. Limited Empirical Analysis of Causal Drivers
While preliminary surveys and stakeholder consultations in Sri Lanka indicate that fishing gear loss arises from environmental, operational, economic, and infrastructural factors, these drivers have not been quantified through systematic empirical investigation. As a result, causal attribution remains descriptive rather than analytical, and policy responses cannot be calibrated to the relative weight of different loss mechanisms. The absence of structured causal modeling represents a major weakness in the national evidence base.
Environmental drivers, particularly monsoonal weather systems, are frequently cited by fishers as a primary cause of gear loss in marine fisheries. Sri Lanka experiences biannual monsoon regimes that alter wave height, current velocity, and coastal circulation patterns. However, there is no dataset linking reported gear loss events to specific meteorological or oceanographic conditions. No statistical correlation analysis has been conducted between seasonal wind intensity, storm frequency, or anomalous wave events and documented gear loss frequency. Without coupling fisheries data with meteorological and oceanographic datasets, it is impossible to determine whether losses are concentrated during specific seasonal windows or distributed evenly across the year. This prevents climate adaptive management and undermines the ability to forecast high risk periods for gear loss.
Operational drivers remain similarly underexamined. Gear conflict between fleets, particularly between trawlers, gillnetters, and small scale nearshore operators, is commonly referenced as a source of entanglement and damage leading to abandonment. Yet no incident reporting system documents gear conflict frequency, location, or severity. The absence of a formalized dispute or loss reporting registry prevents quantification of inter fleet interaction as a causal pathway. Without spatially explicit records of conflict zones, marine spatial planning cannot incorporate gear loss risk as a management variable.
Snagging on coral reefs, rocky substrates, or artificial structures is another frequently mentioned cause of loss. However, Sri Lanka lacks seabed interaction studies that quantify entanglement rates by habitat type. There are no data comparing loss frequency in reef associated fisheries versus sandy bottom trawl grounds or lagoon environments. Consequently, the interaction between fishing effort distribution and habitat vulnerability remains speculative. Preventive measures such as gear modification, depth restriction, or habitat specific zoning cannot be justified without empirical habitat interaction data.
Economic drivers are particularly important but poorly quantified. Gear retrieval involves time, fuel, and labor costs. If the expected economic return from retrieval is lower than the cost of recovery or replacement, fishers may rationally abandon damaged gear. However, no economic threshold modeling has been undertaken to determine the cost recovery break point at which abandonment becomes economically preferable. There are no datasets documenting replacement cost per gear type, average repair expenditure, or retrieval attempt rates. Without economic analysis, policymakers cannot design deposit return systems, compensation schemes, or insurance mechanisms tailored to fisher incentives.
Behavioral and institutional drivers also lack structured investigation. In some cases, disposal of damaged gear at sea or nearshore may be influenced by limited awareness of environmental impacts or lack of disposal facilities at landing sites. Yet there has been no nationally representative behavioral survey assessing fisher knowledge, attitudes, and disposal practices. Without understanding whether improper disposal stems from deliberate behavior, infrastructural constraint, or regulatory ambiguity, management responses risk being misdirected. For example, awareness campaigns are ineffective if the underlying constraint is absence of waste reception facilities.
Infrastructure related causes are particularly critical in the context of fishing gear waste. Landing sites vary widely in terms of solid waste management capacity. Some sites may lack designated collection points for damaged nets, while others may lack transport pathways to recycling or disposal centers. However, there is no national audit quantifying infrastructure availability, capacity, or utilization rates at fisheries landing sites. The absence of such an audit prevents assessment of whether waste leakage is primarily behavioral or systemic. Management interventions cannot prioritize facility investment without baseline infrastructure data.
Regulatory design itself may contribute to causal dynamics. Sri Lanka does not mandate reporting of gear loss, nor does it impose retrieval obligations or penalties linked to abandonment. In the absence of regulatory requirements, fishers have no administrative incentive to document losses or attempt retrieval beyond personal economic motivation. Yet there has been no policy analysis evaluating how regulatory design influences loss reporting or retrieval behavior. Without examining institutional incentives, causal analysis remains incomplete.
Inland fisheries exhibit additional causal uncertainty. Reservoir fisheries operate under variable water level regimes, and gear may be lost due to fluctuations in water depth, submerged vegetation, or infrastructure entanglement. However, no empirical assessment links hydrological variability to gear loss frequency in freshwater systems. Irrigation releases, sedimentation patterns, and structural obstructions may influence entanglement rates, but these interactions remain undocumented. The absence of inland causal analysis perpetuates the exclusion of freshwater systems from management planning.
The cumulative consequence of these deficiencies is that causal attribution in Sri Lanka remains qualitative rather than quantitative. Policymakers cannot rank drivers by magnitude, cannot distinguish between dominant and secondary causes, and cannot assess the relative effectiveness of alternative interventions. Preventive strategies require understanding whether environmental variability, fleet conflict, economic rationality, infrastructure gaps, or regulatory design contribute most significantly to loss. In the absence of such analysis, interventions risk addressing symptoms rather than structural drivers.
Furthermore, without quantified driver analysis, predictive modeling is impossible. Early warning systems for high loss periods, habitat specific risk mapping, or economic incentive calibration depend on empirical relationships between causal variables and loss outcomes. Sri Lanka’s current data architecture does not support such modeling. Governance therefore remains reactive, responding to visible accumulation rather than preventing loss at source.
In summary, empirical analysis of causal drivers in Sri Lanka is constrained by the absence of meteorological correlation studies, operational incident reporting systems, habitat interaction data, economic threshold modeling, behavioral surveys, infrastructure audits, regulatory incentive analysis, and inland hydrological assessment. These gaps prevent the development of targeted preventive policies and undermine the effectiveness of management interventions aimed at reducing abandoned lost and discarded fishing gear and fishing gear waste.
4. Deficiencies in Management and Monitoring Architecture
The management and monitoring architecture governing abandoned lost and discarded fishing gear and fishing gear waste in Sri Lanka is structurally underdeveloped. The problem does not lie solely in insufficient data collection, but in the absence of an institutionalized system that integrates reporting, verification, data storage, cross agency coordination, and performance evaluation. As a result, even when information is generated, it does not translate into adaptive governance or measurable management outcomes.
A fundamental deficiency is the absence of mandatory reporting requirements for gear loss. Sri Lanka’s fisheries regulations require documentation of vessel registration, licensing, and catch landings, yet they do not obligate fishers to record or report gear loss incidents. No standardized logbook format includes fields for location of loss, gear type, cause of loss, retrieval attempt, or estimated mass. Without a regulatory obligation, reporting remains voluntary and episodic. This creates systematic underreporting bias and prevents the formation of a national incident database. From a governance perspective, the absence of mandatory reporting removes the possibility of generating real time spatial intelligence on recurrent loss zones or high risk practices.
Closely linked to reporting deficiency is the absence of gear marking or traceability systems. Fishing gear in Sri Lanka is not required to carry unique identifiers that link lost gear to specific vessels or operators. Without gear marking, it is impossible to attribute recovered nets to responsible parties, which weakens accountability mechanisms. Traceability systems serve not only enforcement purposes but also data collection functions by enabling correlation between fleet segments and observed debris. The lack of traceability prevents both deterrence of deliberate abandonment and statistical linkage between observed waste and source sectors.
Institutional fragmentation further undermines monitoring capacity. Fisheries authorities oversee fleet licensing and resource management, while environmental agencies manage marine pollution programs. Local government bodies are responsible for solid waste at landing sites. These institutions operate under separate legislative frameworks, data management systems, and reporting channels. There is no centralized digital platform that aggregates data related to gear loss, retrieval operations, waste disposal volumes, or recycling outputs. Consequently, even when individual agencies collect partial information, it is not synthesized into an integrated national dataset. This fragmentation impedes cross sector analysis and diffuses accountability across administrative boundaries.
The absence of a centralized database has direct implications for policy evaluation. Management interventions, such as awareness campaigns, cleanup initiatives, or infrastructure improvements at landing sites, cannot be evaluated against baseline indicators because those indicators are not formally established or stored in a unified system. For example, if a coastal cleanup removes several tonnes of discarded nets, there is no national reference point to determine whether this represents a meaningful proportion of annual loss. Similarly, if new waste bins are installed at landing sites, there is no pre intervention dataset documenting baseline disposal practices. Performance measurement therefore becomes anecdotal rather than quantitative.
Monitoring of retrieval operations is also weak. In instances where government agencies, non governmental organizations, or community groups conduct underwater net removal or beach cleanup campaigns, documentation typically records the quantity removed during that specific event. However, there is no system that compares retrieved volumes against estimated total stock, nor any mechanism that tracks whether retrieval reduces recurrence in specific areas. Retrieval is treated as an isolated activity rather than as part of a structured management cycle that includes baseline assessment, intervention, monitoring, and reassessment. Without integration into a monitoring framework, retrieval activities cannot inform adaptive management.
Another structural limitation concerns the absence of performance indicators embedded within fisheries management plans. Fisheries management in Sri Lanka traditionally focuses on catch regulation, effort control, and licensing. Gear loss and waste reduction are not incorporated as measurable objectives within fisheries management plans or coastal zone management strategies. Because ALDFG and FGW are not codified as performance metrics, they do not receive systematic monitoring attention. The omission of explicit targets, such as reduction in annual loss rate or increase in retrieval percentage, removes the incentive for agencies to collect consistent data.
Financial tracking is similarly deficient. There is no accounting framework that documents public expenditure on gear related cleanup, infrastructure provision, or awareness programs. Without linking financial inputs to measurable environmental outputs, cost effectiveness analysis is impossible. Decision makers cannot evaluate whether investments in infrastructure, enforcement, or education yield proportional reductions in loss or waste accumulation. In the absence of cost effectiveness data, budget allocation becomes reactive and politically driven rather than evidence based.
The inland fisheries sector again illustrates monitoring exclusion. Reservoir and freshwater management authorities do not systematically track fishing gear waste as part of environmental oversight. No monitoring protocols exist for documenting net accumulation in freshwater systems, nor are there reporting requirements for inland fishers. Because inland fisheries operate under different administrative arrangements from marine fisheries, integration into national gear monitoring frameworks is absent. This omission perpetuates incomplete national accounting and weakens the comprehensiveness of management architecture.
Data transparency and accessibility represent additional constraints. Even where small scale studies or pilot assessments have been conducted, their results are not embedded in publicly accessible national repositories. The absence of open access national datasets prevents independent verification, academic analysis, and cross sector collaboration. A monitoring architecture that does not facilitate data sharing limits innovation and reduces the potential for interdisciplinary research contributions to policy refinement.
The combined effect of these management and monitoring deficiencies is the absence of a closed governance loop. Effective environmental management requires a cycle of baseline measurement, intervention design, implementation, monitoring, evaluation, and adjustment. In Sri Lanka, the cycle is incomplete because baseline data are weak, reporting is voluntary, data are fragmented, performance indicators are absent, and evaluation mechanisms are not institutionalized. Consequently, governance remains event driven rather than system driven.
From a decision making perspective, these structural weaknesses prevent prioritization, targeting, and accountability. Without spatially resolved reporting, enforcement cannot concentrate on high loss zones. Without traceability, deterrence mechanisms are ineffective. Without centralized data integration, cross agency planning is constrained. Without performance indicators, adaptive management cannot function. The management architecture therefore lacks the informational backbone required for evidence based governance of abandoned lost and discarded fishing gear and fishing gear waste in Sri Lanka.
5. Absence of Ecological Impact Quantification
One of the most critical weaknesses in Sri Lanka’s evidence base on abandoned lost and discarded fishing gear and fishing gear waste is the near complete absence of quantified ecological impact assessment. While anecdotal observations and general marine debris surveys acknowledge that fishing gear contributes to environmental degradation, there are no systematic empirical studies measuring the magnitude, spatial extent, or biological consequences of these impacts within Sri Lankan marine, coastal, or inland ecosystems. This absence has significant implications for fisheries management, biodiversity conservation, and environmental policy integration.
Ghost fishing mortality remains entirely unquantified in Sri Lanka. Lost gillnets, trammel nets, and traps may continue to capture fish and non target species long after abandonment, yet there are no experimental deployments, underwater monitoring studies, or retrieval analyses estimating continued catch per unit effort of abandoned gear. Without such studies, it is impossible to determine how long lost nets remain functionally active in Sri Lankan waters or what proportion of commercially important species are affected. Fisheries stock assessments currently rely on reported landings and regulated catch estimates, but unreported mortality from ghost gear is not incorporated into stock modeling. This omission introduces systematic underestimation of total fishing mortality, potentially biasing assessments of stock health and sustainable yield thresholds.
The absence of species specific entanglement data further weakens ecological understanding. Sri Lanka’s coastal waters host marine turtles, marine mammals, and seabirds, several of which are of conservation concern. However, there are no national datasets documenting the frequency of entanglement events attributable specifically to abandoned fishing gear. Stranding records may occasionally note entanglement, but these are not linked to systematic gear monitoring programs. Without species level impact data, conservation planning cannot evaluate whether ghost gear represents a significant pressure relative to other threats such as bycatch, habitat loss, or pollution. Consequently, environmental prioritization may misallocate resources due to lack of quantified comparative risk.
Habitat level impacts are similarly unmeasured. Coral reefs in Sri Lanka, particularly in western and northwestern coastal regions, have experienced multiple stressors including bleaching, sedimentation, and destructive fishing practices. However, there is no structured program that quantifies net entanglement density on reefs or assesses mechanical abrasion caused by abandoned gear. Reef monitoring programs typically record bleaching extent and physical damage from anchoring but do not categorize fishing gear as a distinct impact variable with standardized metrics. Without consistent habitat interaction monitoring, it is impossible to determine whether reef associated fisheries contribute disproportionately to gear accumulation and structural damage.
Seagrass beds and mangrove systems represent additional unexamined domains. Lost nets can smother seagrass meadows or become entangled in mangrove root systems, affecting nursery habitat function. Yet no field surveys quantify net presence within these habitats, nor is there remote sensing integration to detect accumulation patterns. In the absence of such data, habitat protection policies cannot incorporate gear related pressures into zoning or restoration planning.
The problem extends to freshwater ecosystems. Inland reservoirs and tanks support fish populations that contribute to food security and rural livelihoods. Lost nets in these systems may entangle non target species or degrade benthic habitats. However, there are no studies quantifying freshwater ghost fishing mortality or assessing ecological consequences of submerged synthetic gear in reservoirs. Because inland fisheries operate within hydrologically dynamic systems, gear may accumulate near dam infrastructure or submerged vegetation, but these areas have not been surveyed systematically. The exclusion of freshwater ecological impact assessment perpetuates the assumption that gear loss is predominantly a marine issue, despite inland fisheries’ substantial contribution to national production.
Another critical gap concerns microplastic generation from degraded fishing gear. Synthetic nets and ropes fragment over time, contributing secondary microplastics to marine and freshwater systems. Sri Lanka has emerging research on microplastics in coastal waters, yet there is no material flow analysis linking degraded fishing gear to microplastic loads. Without polymer specific degradation studies or sampling of net fragments in sediment and biota, it is impossible to quantify the contribution of fishing gear to broader plastic pollution pathways. This disconnect prevents integration of fisheries related waste into national plastic pollution strategies.
Cumulative impact assessment is also absent. Ecological risk depends not only on annual loss flow but on accumulated stock over time. Without baseline stock quantification, it is impossible to model long term ecosystem pressure from legacy gear. The absence of cumulative modeling means that environmental risk assessments underestimate compounding effects, particularly in areas with historically intensive fishing activity.
The absence of ecological quantification has direct implications for environmental impact assessment procedures. Development projects, port expansions, and coastal infrastructure initiatives undergo environmental impact assessments that evaluate pressures such as sedimentation and pollution. However, fishing gear accumulation is not incorporated as a baseline environmental variable because it has not been quantified. This omission results in incomplete environmental baselines and weakens the comprehensiveness of impact mitigation planning.
From a decision-making perspective, the absence of quantified ecological impact creates an evidence vacuum that reduces policy urgency. When impacts are not measured, they remain politically and administratively invisible. Budget allocations for gear retrieval or preventive measures compete with other environmental priorities that possess stronger empirical documentation. Without quantified mortality rates, habitat damage indices, or biodiversity impact metrics, gear related pressures struggle to justify resource allocation within constrained environmental budgets.
Furthermore, the absence of ecological data prevents cost benefit analysis of preventive interventions. If ghost fishing mortality were quantified, policymakers could estimate the economic value of fish biomass lost due to abandoned gear. Such valuation could inform incentive mechanisms for retrieval or deposit schemes. Without ecological metrics, economic valuation models cannot be constructed, and preventive investment lacks quantitative justification.
In summary, Sri Lanka lacks empirical quantification of ghost fishing mortality, species specific entanglement rates, habitat level damage, freshwater ecosystem impacts, microplastic contribution from degraded gear, and cumulative stock effects. These ecological data gaps undermine fisheries stock assessment accuracy, weaken biodiversity conservation planning, distort environmental prioritization, and prevent economic valuation of loss. The absence of quantified ecological consequences therefore represents a central constraint on evidence based decision making in the governance of abandoned lost and discarded fishing gear and fishing gear waste.
6. Socioeconomic and Behavioral Data Gaps
The socioeconomic and behavioral dimensions of abandoned lost and discarded fishing gear and fishing gear waste in Sri Lanka remain profoundly underexamined. While technical discussions often frame gear loss as an environmental problem, effective governance depends equally on understanding fisher incentives, cost structures, risk perceptions, and institutional constraints. In Sri Lanka, there is no systematic national dataset quantifying the economic burden of gear loss, nor any structured behavioral research investigating disposal practices, compliance motivations, or barriers to responsible management. This absence limits the design of realistic, enforceable, and socially acceptable policy instruments.
At the most fundamental level, the direct economic cost of gear loss to fishers has not been quantified nationally. Fishing gear represents a substantial capital investment, particularly for gillnet and multi day vessel operators who rely on large net lengths and synthetic line materials. However, there is no comprehensive assessment of replacement cost per gear type, average annual loss per vessel, or cumulative financial impact across fleet segments. Without cost aggregation, policymakers cannot estimate the total economic burden borne by fishing communities. This information is critical for evaluating whether gear loss represents primarily an environmental externality or also a significant private economic loss.
Beyond replacement cost, the opportunity cost of lost gear has not been evaluated. Gear loss may reduce catch efficiency, require downtime for replacement, or necessitate additional fuel expenditure to re deploy fishing effort. These indirect costs can alter income stability, particularly among small scale operators with limited capital reserves. Yet there are no income impact studies assessing how recurrent gear loss affects household earnings or financial resilience. In the absence of income impact modeling, interventions such as mandatory gear marking or deposit schemes cannot be calibrated to avoid disproportionate burden on vulnerable fishers.
Behavioral dimensions are similarly neglected. There is no nationally representative survey examining fisher attitudes toward gear loss, environmental responsibility, or disposal norms. It remains unclear whether improper disposal of damaged nets at sea or nearshore arises from deliberate cost avoidance, lack of awareness, peer norms, or absence of infrastructure. Behavioral economics demonstrates that compliance and environmental stewardship are shaped by social norms, perceived fairness, and trust in institutions. Without empirical behavioral data, policy instruments risk misdiagnosing the problem. For example, awareness campaigns may be ineffective if the primary constraint is absence of disposal facilities rather than lack of knowledge.
The design of incentive based mechanisms requires robust socioeconomic data that are currently unavailable. Deposit return schemes for fishing gear, which require fishers to pay an upfront refundable fee redeemable upon proper disposal, depend on understanding price sensitivity and liquidity constraints. If fishers operate with limited working capital, even small deposits may discourage participation. Without data on cash flow cycles, seasonal income variability, and credit access, policymakers cannot determine the feasibility of such schemes. Similarly, compensation mechanisms for retrieved ghost gear require valuation of retrieval effort relative to expected catch revenue. No such valuation studies have been conducted in Sri Lanka.
Inland fisheries illustrate an additional socioeconomic blind spot. Reservoir and lagoon fisheries often involve lower income, small scale operators who may rely heavily on inexpensive synthetic nets. Yet no research has examined disposal practices, reuse behavior, or informal recycling of gear in these communities. Because inland fishers often operate outside formalized marine governance structures, policy instruments designed for marine fleets may not translate effectively. The absence of socioeconomic profiling across marine and inland sectors prevents differentiation of policy tools according to capacity and vulnerability.
Another significant gap concerns the informal recycling and secondary market pathways for fishing gear. Damaged nets may be repurposed for agricultural fencing, household use, or informal resale. However, there is no material flow analysis documenting post use pathways of fishing gear within coastal and inland communities. Without understanding secondary use markets, policymakers cannot evaluate whether formal recycling systems would compete with existing informal economies or disrupt livelihood strategies.
Gender dimensions are also unexamined. Women in fishing households often participate in net mending, processing, or waste handling. Yet there is no gender disaggregated research examining how gear loss or disposal practices affect household labor distribution or income diversification. Ignoring gendered roles limits the comprehensiveness of socioeconomic analysis and may overlook critical intervention points.
The absence of compliance and enforcement perception studies further weakens policy design. Effective regulation depends on understanding how fishers perceive enforcement probability, penalty severity, and institutional legitimacy. Sri Lanka has not conducted surveys examining whether fishers would respond to mandatory reporting requirements or penalties for abandonment. Without understanding compliance psychology, regulatory instruments risk low adherence or unintended resistance.
Socioeconomic valuation of environmental loss is another missing component. Ghost fishing may remove commercially valuable biomass from the ecosystem, representing both ecological and economic loss. However, no study has quantified the potential market value of fish lost due to abandoned gear. Without economic valuation of environmental damage, policymakers cannot perform cost benefit analysis comparing preventive investment with avoided ecological loss. The absence of valuation data weakens the fiscal case for intervention.
Additionally, there is no integration of socioeconomic data into national marine pollution or fisheries management planning frameworks. Fisheries management plans focus primarily on catch limits and effort control, while socioeconomic monitoring concentrates on income and employment statistics. Fishing gear waste is not incorporated as a variable within socioeconomic resilience assessments. This omission prevents recognition of gear loss as both an environmental and livelihood issue.
From a decision making perspective, the absence of socioeconomic and behavioral data constrains the selection of appropriate policy instruments. Regulatory measures, incentive schemes, infrastructure investment, and awareness campaigns each require distinct socioeconomic assumptions. Without empirical data on fisher cost structures, behavioral drivers, and community norms, policy design becomes speculative. Interventions may impose unintended economic hardship, fail to change behavior, or create perverse incentives.
In summary, Sri Lanka lacks quantified data on gear replacement costs, income impacts, opportunity costs, behavioral drivers of disposal, compliance perceptions, informal recycling pathways, gender dimensions, inland fisher vulnerability, and economic valuation of ecological loss. These gaps prevent evidence based calibration of regulatory and incentive based instruments. Without socioeconomic and behavioral integration, governance of abandoned lost and discarded fishing gear and fishing gear waste remains environmentally framed but economically under informed, limiting the effectiveness and sustainability of policy responses.
7. Implications for Evidence Based Decision Making and Governance Performance
The cumulative data deficiencies identified across quantification, causation, ecological assessment, socioeconomic analysis, and monitoring architecture do not merely represent academic gaps. They create systemic distortions in decision making across fisheries governance, environmental management, and resource allocation in Sri Lanka. The absence of comprehensive and integrated data undermines the fundamental components of evidence-based policy: problem definition, prioritization, instrument selection, implementation targeting, and performance evaluation.
At the problem definition stage, insufficient quantification of national magnitude prevents accurate characterization of the scale of ALDFG and fishing gear waste. Without a statistically defensible baseline covering marine, coastal, and inland systems, policymakers cannot determine whether gear loss constitutes a marginal issue or a significant structural environmental pressure. This ambiguity weakens agenda setting. Environmental governance frameworks tend to prioritize issues with measurable indicators, such as reported catch decline or documented pollution loads. In contrast, fishing gear waste remains partially invisible because its magnitude is not formally established. As a result, it may receive lower political and administrative priority relative to issues with clearer empirical grounding.
Prioritization failure follows from spatial and sectoral blind spots. Without georeferenced loss data or habitat overlay mapping, decision makers cannot identify hotspots where intervention would yield maximum environmental benefit. Resource allocation therefore risks being evenly distributed or opportunistically directed rather than strategically targeted. For example, cleanup campaigns may occur in highly visible coastal areas while submerged accumulation zones in offshore reefs remain unaddressed. Inland fisheries, lacking any quantification, are excluded entirely from prioritization frameworks. This creates geographic and ecological inequity in management attention.
Instrument selection is similarly compromised by causal uncertainty. Effective policy design depends on understanding the relative contribution of environmental, operational, economic, and institutional drivers. In Sri Lanka, the absence of quantified causal attribution prevents differentiation between preventive strategies. If monsoonal weather is a dominant driver, adaptation strategies may include seasonal zoning or gear modification standards. If economic thresholds drive abandonment, deposit refund or compensation mechanisms may be appropriate. If infrastructure deficiency is the primary constraint, investment in landing site facilities would be justified. Without empirical weighting of drivers, instrument choice becomes speculative, increasing the risk of ineffective or misaligned interventions.
Regulatory design suffers from the absence of behavioral and compliance data. Mandatory reporting requirements, penalties for abandonment, or gear marking systems require an understanding of fisher response to enforcement probability and sanction severity. In the absence of compliance perception studies, regulatory instruments may either lack deterrent power or provoke resistance. Overly punitive measures without socioeconomic grounding may disproportionately burden small scale fishers, while weakly designed rules may fail to alter behavior. Governance effectiveness therefore depends on socioeconomic insight that is currently missing.
Monitoring and evaluation represent another major governance failure pathway. Effective environmental management requires measurable indicators and baseline reference points against which progress can be assessed. Sri Lanka lacks baseline stock estimates of accumulated gear, annual loss flow stratified by fleet segment, and ecological impact metrics such as ghost fishing mortality rates. Without such indicators, policymakers cannot determine whether implemented measures reduce gear loss or merely create visible but temporary improvements. Cleanup operations, awareness campaigns, or infrastructure investments cannot be evaluated for cost effectiveness because outcome metrics are undefined. This absence of performance measurement prevents adaptive management and institutional learning.
Fiscal decision making is also constrained. Budget allocation within environmental and fisheries ministries competes across multiple priorities. Without quantified economic valuation of ecological loss from ghost fishing or habitat degradation, fishing gear waste struggles to justify dedicated funding. Cost benefit analysis requires comparison between intervention cost and avoided environmental damage. Because ecological and socioeconomic impacts are not monetized or quantified, preventive investment lacks fiscal justification. Consequently, funding decisions may be driven by visibility or external donor interest rather than by structured economic reasoning.
The absence of integrated data architecture further weakens interagency coordination. Fisheries authorities, environmental agencies, and local governments operate within separate data systems, limiting cross sector planning. Integrated coastal zone management and marine spatial planning processes require spatially resolved data on environmental pressures. Without incorporation of ALDFG as a mapped variable, planning exercises omit a potentially significant anthropogenic stressor. This exclusion reduces the comprehensiveness of marine planning frameworks.
International reporting and compliance also suffer. Global marine pollution and biodiversity frameworks increasingly emphasize measurable indicators and reporting transparency. Without nationally consolidated datasets on gear loss and waste management, Sri Lanka’s reporting capacity is constrained. This may limit access to technical and financial support mechanisms that depend on demonstrable baselines and progress metrics. The absence of robust data therefore has implications beyond domestic governance, affecting international engagement and funding opportunities.
Risk assessment frameworks are particularly compromised. Environmental risk assessment requires quantification of exposure, vulnerability, and consequence. Sri Lanka lacks reliable exposure data in the form of national stock and flow estimates. Vulnerability mapping is incomplete because habitat interaction data are absent. Consequence quantification is missing because ecological mortality and habitat damage are not measured. Without these components, risk cannot be systematically ranked or compared against other environmental threats. Policy therefore operates under high uncertainty, often defaulting to reactive responses after visible accumulation occurs.
Long term strategic planning is weakened by temporal discontinuity in data. Without multi year time series, policymakers cannot distinguish between episodic anomalies and structural trends. Climate variability, technological shifts in gear materials, and changes in fleet composition may alter loss dynamics over time. In the absence of temporal data continuity, adaptive planning becomes impossible. Governance remains static while environmental and socioeconomic conditions evolve.
The exclusion of inland fisheries introduces a systemic bias in national assessment. Because inland systems are not quantified, national policy may underestimate total environmental load and neglect freshwater ecosystem impacts. This sectoral omission distorts overall national strategy and undermines claims of comprehensive marine and fisheries governance.
Collectively, these decision failures illustrate that the data problem is not peripheral but foundational. Evidence based governance depends on reliable, integrated, and longitudinal data systems. In Sri Lanka, the absence of standardized quantification, causal attribution, ecological impact assessment, socioeconomic analysis, and centralized monitoring architecture creates structural uncertainty. This uncertainty propagates through every stage of policy design and implementation, from agenda setting to evaluation.
In conclusion, the insufficiency of comprehensive data on the extent, causes, and management of abandoned lost and discarded fishing gear and fishing gear waste in Sri Lanka constrains governance at multiple levels. It distorts prioritization, weakens instrument calibration, prevents performance evaluation, limits fiscal justification, and undermines risk assessment. Addressing these deficiencies is therefore not simply research imperative but a prerequisite for effective, accountable, and adaptive fisheries and environmental management.
Challenges and Limitations in Food Dehydration and Drying in Sri Lanka: A Review.
Review Article by P. M. N. Mihirani and W. R. W. M. S. N. P. Weerakoon (2020)
Read this article on ResearchGate
Challenges and Limitations in Food Dehydration and Drying in Sri Lanka: A Review
P. M. N. Mihirani1 and W. R. W. M. S. N. P. Weerakoon2
1Institute of Sustainable Agricultural, Food, and Environmental Sciences, Sri Lanka.
2Department of Agriculture, Sri Lanka.
Abstract
Food dehydration and drying are critical post-harvest preservation strategies in Sri Lanka, where high humidity, seasonal rainfall, and limited cold chain infrastructure contribute to significant losses of perishable agricultural products. These processes are widely applied across fruits, vegetables, spices, plantation crops, fisheries, medicinal plants, and other biological materials to extend shelf life, stabilize quality, and enable value addition. Despite their importance, drying and dehydration systems in Sri Lanka face persistent challenges related to climate variability, energy access, process control, hygiene, and technical capacity. At the same time, structural limitations arising from technology design, institutional fragmentation, market constraints, and supply chain inefficiencies restrict performance, scalability, and competitiveness. This narrative review critically synthesizes published scholarly literature and national studies to examine these challenges and limitations while maintaining clear conceptual distinctions between drying and dehydration, and between challenges and limitations. The review integrates evidence from multiple commodity sectors and highlights key knowledge gaps and priorities for research, policy, and technological development to strengthen food preservation outcomes and agri food system resilience in Sri Lanka.
1. Introduction
Sri Lanka’s agricultural and fisheries sectors are characterized by the production of a wide diversity of high moisture commodities, including fruits, vegetables, spices, plantation crops, fish, leafy greens, roots and tubers, and medicinal plants. These products are biologically active and highly susceptible to spoilage under tropical conditions, particularly in the absence of adequate cold storage and controlled handling systems. Post harvest losses therefore remain a major constraint to food security, farmer incomes, and value chain efficiency.
Numerous studies have documented substantial post-harvest losses in Sri Lanka, particularly for fruits and vegetables, with reported losses ranging from approximately 15 percent to 40 percent depending on commodity type, season, and supply chain characteristics (Rajapaksha et al., 2021; Wasala et al., 2025). Losses also occur in fisheries, spices, and plantation crops, where improper drying and storage can lead to microbial spoilage, insect infestation, and quality degradation.
Drying and dehydration are among the most widely used preservation strategies to address these losses. Traditional drying methods such as sun drying and open-air drying are deeply embedded in Sri Lankan food systems, while mechanical and solar assisted dehydration technologies have gained attention for their potential to improve product quality and market access. However, outcomes remain uneven due to conceptual ambiguity between drying and dehydration, and due to insufficient consideration of the distinct challenges and limitations affecting each process. This review provides a comprehensive synthesis of these issues across multiple sectors.
2. Methodology
This study adopts a structured narrative review methodology. Peer reviewed journal articles, academic theses, institutional research reports, and policy documents related to food drying, dehydration, and post-harvest management in Sri Lanka were identified through searches of academic databases and publicly accessible repositories. Search terms included Sri Lanka, food drying, dehydration, post-harvest loss, fruit processing, vegetable processing, spice drying, fish drying, and value addition.
Sources were screened for relevance to Sri Lanka and for their contribution to understanding process performance, quality outcomes, technological systems, or systemic constraints. Priority was given to studies presenting empirical data, sectoral analyses, or case studies specific to Sri Lanka. Where Sri Lanka specific evidence was limited, studies from comparable tropical contexts were used to support interpretation. The literature was synthesized narratively and organized thematically, without quantitative meta-analysis, consistent with established approaches to narrative reviews.
3. Conceptual Framework
3.1 Drying
Drying refers to the removal of moisture from food materials through exposure to heat and air movement, often under ambient or semi controlled conditions. In Sri Lanka, drying is commonly practiced through sun drying, open racks, mats, and rudimentary hot air systems. The primary objective is to reduce moisture content to levels that delay spoilage and extend shelf life. Drying practices are typically dependent on weather conditions and operator experience, resulting in variability in moisture reduction, quality, and safety outcomes.
3.2 Dehydration
Dehydration is a controlled food preservation process in which temperature, airflow, humidity, and time are regulated to achieve defined moisture content or water activity targets. Dehydration aims to preserve sensory attributes, nutritional quality, functional properties, and rehydration capacity in addition to extending shelf life. Mechanical hot air dehydration, solar assisted dehydration, and hybrid systems fall within this category. Dehydration generally requires higher capital investment, reliable energy supply, and technical expertise compared to traditional drying.
3.3 Challenges and Limitations
In this review, challenges are defined as contextual factors that complicate effective application of drying and dehydration, including climatic variability, energy access, skill constraints, and operational conditions. Limitations refer to inherent or structural constraints within technologies, institutions, markets, and supply chains that restrict performance, scalability, or long-term sustainability.
4. Post Harvest Loss Context in Sri Lanka
4.1 Fruits and Vegetables
Post harvest losses of fruits and vegetables in Sri Lanka are consistently reported as high. Studies estimate that between 30 percent and 40 percent of fruits and vegetables are lost across harvesting, handling, transport, storage, and processing stages (Rajapaksha et al., 2021; Wasala et al., 2025). Key drivers include mechanical damage during harvesting, inadequate packaging, exposure to high ambient temperatures, lack of cold chain infrastructure, and delays between harvest and processing.
Drying and dehydration offer opportunities to reduce these losses, particularly during periods of seasonal surplus for crops such as mango, pineapple, banana, jackfruit, papaya, tomato, and leafy vegetables. However, the effectiveness of these processes depends on timely application and adequate control of moisture removal.
4.2 Spices and Plantation Crops
Sri Lanka is internationally recognized for spice production, particularly cinnamon, pepper, cloves, nutmeg, and cardamom. Drying is a critical step in spice processing and directly influences aroma, color, oil content, and storage stability. Traditional sun drying is widely used but is highly sensitive to weather conditions, leading to quality variability and contamination risks. In plantation crops such as coconut, drying processes are central to products such as copra, where inadequate drying can promote fungal growth and mycotoxin formation.
4.3 Fisheries, Medicinal Plants, and Other Products
Drying of fish is an important livelihood activity in coastal regions, enabling preservation of surplus catch. However, uncontrolled drying conditions, poor hygiene, and inconsistent moisture reduction contribute to quality deterioration and food safety concerns (ICSF, 2016). Similar issues arise in drying of leafy vegetables, roots and tubers, and medicinal plants, which are often processed informally with limited technical guidance.
5. Challenges in Drying Practices
5.1 Climatic Challenges
Sri Lanka’s tropical climate presents fundamental challenges to drying. High relative humidity reduces the moisture gradient between food and surrounding air, slowing drying rates and increasing equilibrium moisture content. Frequent rainfall, particularly during monsoon seasons, disrupts sun drying cycles and leads to moisture reabsorption. These conditions increase the risk of microbial growth, enzymatic activity, and spoilage.
5.2 Quality Degradation
Uncontrolled drying can result in uneven moisture removal, surface hardening, discoloration, and loss of volatile compounds. Prolonged exposure to heat, oxygen, and sunlight accelerates degradation of heat sensitive vitamins and bioactive compounds, reducing nutritional value. In fruits and vegetables, such quality deterioration strongly affects consumer acceptance and marketability.
5.3 Hygiene and Food Safety
Open drying systems expose food to dust, insects, birds, rodents, and domestic animals. Inadequate sanitation during handling and drying increases the risk of microbial contamination and food borne illness. Limited awareness of good manufacturing practices and lack of basic infrastructure exacerbate these risks in small scale operations.
6. Challenges in Dehydration Systems
6.1 Energy Availability and Cost
Dehydration systems require reliable energy to maintain controlled temperature and airflow. In Sri Lanka, electricity costs are relatively high, and access to stable grid power is limited in many rural areas. Biomass fueled systems face challenges related to fuel quality, emissions, and temperature control. Solar assisted dehydration systems offer potential benefits but require careful design to address intermittency and high humidity conditions (Esper and Muhlbauer, 1998).
6.2 Technical Capacity and Operation
Effective dehydration depends on understanding drying kinetics, moisture targets, pre treatment methods such as blanching or osmotic dehydration, and process monitoring. Limited access to training and extension services results in suboptimal operation of dehydration equipment, reduced efficiency, and inconsistent product quality.
6.3 Scale and Supply Constraints
Most dehydration initiatives operate at small or pilot scale. Irregular raw material supply due to seasonality, lack of aggregation mechanisms, and limited working capital constrain system utilization and prevent economies of scale. These challenges are particularly evident in fruit and vegetable dehydration.
7. Structural Limitations
7.1 Technological Limitations
Many drying and dehydration systems used in Sri Lanka rely on outdated or poorly optimized designs. Locally fabricated dryers often lack validated performance data and exhibit uneven airflow and temperature distribution. Advanced dehydration technologies such as vacuum drying or freeze-drying offer superior quality outcomes but remain largely inaccessible due to high capital and operational costs.
7.2 Institutional and Policy Limitations
Institutional responsibilities for post-harvest management, food processing, and technology development are fragmented across multiple agencies. Limited coordination reduces the effectiveness of research dissemination, technology transfer, and standard setting. Weak enforcement of quality and safety standards reduces incentives for upgrading drying and dehydration practices.
7.3 Market and Economic Limitations
Domestic markets for dried and dehydrated products are price sensitive, limiting willingness to pay for higher quality products. Export markets offer opportunities but require compliance with stringent quality, safety, and traceability requirements that many small and medium enterprises struggle to meet (Dissanayake et al., 2024).
8. Knowledge and Supply Chain Limitations
Variability in raw material quality, lack of cold chain infrastructure, and fragmented supply chains introduce uncertainty into drying and dehydration processes. Limited dissemination of research findings and inadequate training constrain adoption of improved practices. Many operators rely on experiential knowledge rather than scientifically validated methods, leading to inconsistent outcomes.
9. Discussion and Synthesis
The challenges and limitations affecting drying and dehydration in Sri Lanka are deeply interconnected. Climatic constraints amplify technological weaknesses, while institutional and market limitations restrict the diffusion of improved solutions. Addressing these issues requires integrated approaches that combine appropriate technology development, renewable energy integration, capacity building, supply chain coordination, and supportive policy frameworks.
10. Conclusion
Drying and dehydration are vital components of Sri Lanka’s food preservation landscape, with relevance across fruits, vegetables, spices, plantation crops, fisheries, and other biological products. However, their effectiveness is constrained by environmental challenges and structural limitations that reduce quality, safety, and scalability. Clear differentiation between drying and dehydration, combined with targeted investments in technology, skills, and governance, is essential to reduce post-harvest losses, improve food security, and strengthen agri food system resilience in Sri Lanka