Adoption of Solid Waste Compost in Paddy Farming: Insights from Sri Lanka’s Organic Farming Policy

Abstract

The utilization of Solid Waste Compost (SWC) as an organic fertilizer (OF) in agriculture has garnered significant attention in recent years due to growing concerns about worsening waste management issues. This empirical study investigates paddy farmers’ perceptions of SWC under Sri Lanka’s organic farming policy and uniquely addresses its underexploited potential as an organic fertilizer. Data were collected from 254 respondents in the Attanagalla Divisional Secretariat Division via a structured questionnaire. Nine key performance indicators were established to evaluate SWC against other organic fertilizers considered for the study. Findings revealed that meeting the ‘required quantity’ OF was the most challenging aspect (91%) for organic paddy cultivation, while only 14.2% of paddy farmers were able to utilize SWC for paddy fields due to limited availability. Farmers appreciated SWC as the most effective in balancing pest–predator interactions, even surpassing straw; however, its availability lagged compared to alternatives such as straw. Farmers expressed a higher likelihood of adopting SWC if it met government certification standards. The findings conclude that, while increasing production of SWC could enhance its role as an organic fertilizer in paddy farming, achieving its quality standards for paddy farming through government standard certification is crucial for successful implementation.

1. Introduction

Agriculture is essential for the economic growth of developing countries such as Sri Lanka, where rice is the primary income source for 1.8 million farmers and a staple for 22.15 million people. About 50% of Sri Lanka’s 1,371,600 hectares of arable land is dedicated to paddy cultivation [1]. In 2020, Sri Lanka spent approximately USD 253 million on imported inorganic fertilizers, highlighting its heavy dependence on these inputs [2]. The excessive utilization of these fertilizers has resulted in environmental degradation [3,4,5,6]. In response to this issue and to promote organic farming practices, the Government of Sri Lanka (GOSL) implemented the Imports and Exports (Control) Regulation No. 07/2021 on 6 May 2021, which prohibited the use of Chemical Fertilizers (CFs) and agrochemicals [7]. Consequently, in 2022, the Volume Index of Agricultural Production decreased by 4.6% [8]. The policy stimulated more interest in organic farming, even though it was later changed in 2022. This circumstance highlights a misalignment between the goals of legislation and actual results, especially regarding the accessibility and effectiveness of organic fertilizers (OFs).

The lack of sufficient OFs is a major problem that leads to less-than-ideal organic agricultural methods. There is potential for using Solid Waste Compost (SWC), which is made from Municipal Solid Waste (MSW), which is 62% biodegradable [9], as an OF. Its use in paddy farming is still mostly unknown; nevertheless, it offers a chance to improve organic farming methods and composting.

Previous studies have examined farmers’ attitudes toward organic fertilizers (OFs), globally and locally, focusing on traditional inputs such as straw, cow dung, and poultry excrement. In the global context, Okuma and Isiorhovoja [10] found Nigerian farmers willing to pay for OFs, suggesting awareness campaigns. Aryal et al. [11] studied factors influencing fertilizer use in South Asia but did not focus on SWC. Wang and Zhang [12] used the extended theory of planned behavior to predict individual OF use. In Sri Lanka, studies [13,14,15,16,17] emphasize the need for awareness programs to improve nutrient-use efficiency and reduce environmental impacts of CFs, advocating SWC as a sustainable solution. SWC offers economic benefits by reducing costs and promoting a circular economy through waste reuse. Paddy farmers, significantly affected by organic farming regulations, need their perceptions investigated.

Few studies have examined SWC adoption under Sri Lanka’s organic farming policy. Only six studies [18,19,20,21,22,23] have explored this in Sri Lanka. Malkanthi [18] examined farmers’ attitudes towards organic agriculture, excluding paddy farming. Sandeepani [19] found that paddy farmers believed banning CFs and promoting organic farming could benefit the ecosystem and economy. These studies [18,19] focused on OFs from agricultural by-products, unlike this study’s focus on SWC in paddy farming. Herath et al. [20] reviewed five policy instruments to promote Eco-Friendly Technologies (EFTs) in paddy farming over CFs, stressing the need for a strong institutional framework, but did not examine regulatory implications. This study uniquely examines SWC adoption under new policies, providing insights into farmers’ adaptation and conditions supporting broader SWC use. Chandrasiri et al. [21] emphasized the need for private incentives to reduce costs and better regulate fertilizer markets, as distorted markets hinder EFT adoption. Paranamana [22] found farmers prefer organic fertilizers for their environmental and cost benefits, but noted dissatisfaction with production volume and appearance. Verite Research [23] reported strong farmer support for the new organic farming policy, especially among those growing major crops. While some studies have explored SWC application in Sri Lanka, few have thoroughly investigated paddy farmers’ perspectives on SWC and the broader socio-economic impacts of the country’s organic farming policies. Bridging the gap between compost demand and supply for paddy farming remains challenging.

This study addresses this gap by focusing on paddy farmers’ perceptions of SWC as a viable alternative to traditional OFs and its novelty lies in evaluating via nine Key Performance Indicators (KPIs) of SWC, ((1) soil fertility, (2) soil water retention capacity, (3) pest- predator ratio, (4) weed composition, (5) possible health hazards in use, (6) price/cost of production, (7) yield/hectare, (8) durability, and (9) timely availability), providing new nuanced insights and comprehensive, multi-dimensional evaluation framework in comparison to other OFs in sustainable paddy farming. This novel approach not only addresses this gap but also identifies conditions necessary for its broader acceptance in Sri Lanka’s sustainable waste management and agricultural policies and makes it applicable to similar contexts globally.

2. Materials and Methods

2.1. Study Area

The Attanagalla Divisional Secretariat Division (ADSD), a semi-urban area, was selected for its significance in paddy farming as a primary livelihood and relevance to Sri Lanka’s organic farming policy. Paddy cultivation in this area is primarily dependent on rain-fed irrigation systems. In this key hub of paddy cultivation, a total of 1574 hectares, which accounts for 10.56% of the land, are dedicated to paddy cultivation, and 3570 farmers engage in paddy cultivation [1]. ADSD provides a representative sample of small- and medium-scale farmers, reflecting broader agricultural trends. Its active participation in organic farming initiatives, reliance on rain-fed irrigation systems, and accessibility to key stakeholders make it an ideal setting to assess the practical adoption of SWC. Additionally, its proximity to urban centers makes it an ideal model to study the integration of SWC to paddy farming with the alignment of the national policy shift towards organic farming.

2.2. Sampling and Data Collection

We visited the study area, and respondents were identified in coordination with local agrarian officials. Using the Cochran formula [24] and a 90% confidence level, data were collected and tabulated from a sample of 254 paddy farmers, which was selected through purposive sampling and using a structured questionnaire from March to May 2023. While the 95% confidence level is widely accepted in social research, the 90% level was deemed appropriate given the study’s exploratory nature and the challenges of accessing a large and diverse sample of paddy farmers within a limited timeframe.

2.3. Questionnaire

This study addresses the following research questions:

(1) What factors influence farmers’ adoption of solid waste compost (SWC) in paddy farming under Sri Lanka’s organic farming policy? and (2) How do farmers’ perceptions of SWC quality and certification affect their willingness to adopt it? Prior to the original survey, a pilot test was conducted to ensure the questionnaire’s accuracy, dependability, and acceptability among ten participants from the study area.

Table 1. A structured questionnaire was used in the survey.

The Structured Questionnaire Used for the Survey
Personal profile	- Gender: Male, Female - Age: Less than 30 years, 30–49 years, 50–69 years, Above 70 years - Education level: Primary, Secondary, Tertiary - Experience in paddy farming: 5–9 yrs, 10–14 yrs, 15–19 yrs, 20 yrs
Farming practices	- Used fertilizer type for paddy before the policy: CF only, OF only, CF and OF combination - Used OF type for agriculture before the policy: straw, cow dung, poultry manure, green manure, fruit and vegetable compost, SWC - Mode of supply on OF for paddy (after policy): Self preparation, Purchase from private sector, Purchase from government sector - Challenge on OF for paddy (after policy): To meet the required quantity, Price, and quality
Awareness of SWC	- Awareness of SWC: Yes, No - Experience of using SWC for paddy (before and after the policy): Yes, No
Willingness and opinion	- Willingness to use SWC for paddy: Yes, No - (If yes, expected requirement related to SWC: Government certification, Government subsidy, Need nothing) - Opinion on Key Performance Indicators (KPIs) for each OF the types
Farmer’s attitudes (5-point Likert scale)	- The standardization of SWC should be solely supported and supervised by the government - SWC is better applied as a mixture of other Agricultural waste for paddy farming - The addition of locally available resources, such as “glirizeediya” leaves to SWC, will increase in nutritional properties of it - Motivating farmers to cultivate “glirizeediya” leaves, buying them by LAs, and returning their benefit to farmers is a positive approach

Note: Responses recorded on a 5-point Likert scale where 1 = Strongly disagree to 5 = Strongly agree.

shows the part of the structured questionnaire that we employed to collect demographic factors, paddy farming practices, awareness of SWC, the willingness to use SWC for rice cultivation, and farmers’ attitudes on quality aspects of SWC. Additionally, paddy farmers’ attitudes on SWC as an organic fertilizer supplement were collected using five statements on a 5-point Likert scale (1 = strongly disagree, 2 = disagree, 3 = neutral, 4 = agree, and 5= strongly agree).

2.4. KPIs for Each of Type

The KPIs serve as the key indicators for assessing farmers’ perspectives on the suitability of SWC with distinct types of OFs in agricultural contexts. Nine KPIs were established based on the practical needs of paddy farmers and the existing literature on the evaluation of organic fertilizers, which illustrates the rationale for the scope of the study namely; (1) soil fertility, (2) soil water retention capacity, (3) pest–predator ratio, (4) weed composition, (5) possible health hazards in use, (6) price/cost of production, (7) yield/hectare, (8) durability, and (9) timely availability. The Study [24] emphasized these indicators as crucial in assessing the efficacy and sustainability of SWC in agricultural systems since soil fertility and yield are often considered primary concerns for farmers, while durability and price reflect the economic feasibility of adopting OFs.

Farmers’ opinions for the six organic fertilizer types considered for this study (straw, cow dung, poultry manure, green manure, fruit, and vegetable waste, and SWC) were analyzed and compared using a 5-point Likert scale. Points for each of the nine KPIs were scored as follows: Very Bad (VB) = 1, Bad (B) = 2, Neutral (N) = 3, Good (G) = 4, and Very Good (VG) = 5.

2.5. Data Analysis

The dataset was initially assessed for normal distribution using the Jarque–Bera test [25], evaluating departure from normality based on sample skewness and kurtosis. Single-factor ANOVA was applied to KPI-related data to determine statistically significant differences. The Bonferroni test [26] was then used as a post hoc test through individual student T-tests and multiple comparisons with the Bonferroni corrected method, controlling the risk of Type I errors in multiple pairwise comparisons. For the post hoc analysis of five pairwise comparisons, including SWC, the original alpha value of 0.05 was adjusted to 0.01 (original alpha value/number of post hoc tests). p-values for all pairwise comparisons were then compared with the Bonferroni corrected alpha value, increasing the likelihood of a post-positive result. Descriptive statistics and correlation analyses were used to summarize relationships among study variables, followed by normality testing and ANOVA as described below

3. Results

3.1. Demographic Profile

Basic demographic information, such as sex, age, and educational level, was found in the study area, and the results are shown in

Table 2. Respondents’ demographic profile.

Parameter	Category	Frequency	Percentage (%)
Gender	Male	211	83.0
	Female	43	17.0
Age	Less than 30 years.	8	3.1
	30–49 years	26	10.2
	50–69 years	157	61.8
	Above 70 years	63	24.9
Education level	Primary	93	36.6
	Secondary	122	48.0
	Tertiary	39	15.4
Paddy farming experience	5–9 years	15	5.9
	10–14 years	44	17.3
	15–19 years	93	36.6
	>20 years	102	40.2

.

Accordingly, 83% of the sample was composed of men, 62% of whom were between the ages of 50 and 69 years and had secondary education as the most common education level (48%). Rice is the staple crop in Sri Lanka, and a substantial land area is devoted to its cultivation. Approximately half of all farm households cultivate rice, primarily for household consumption or domestic sales [27].

We observed the generational disparity in education and farming experiences among farmers. Older farmers (50–69 years and >70 years) predominantly possess primary education, indicating limited access to advanced education in their formative years, and exhibit a clear predominance in >20 years of experience, underscoring their long-term engagement in paddy farming. In contrast, younger farmers (<30 years and aged 30–49 years) demonstrate higher levels of education, yet their farming experience is limited.

3.2. Paddy Farming Practices, Awareness, and Willingness to Use SWC

Paddy Farming Practices

The paddy farming practices before and after the policy were explored to identify farmers’ tendency for fertilizers and adoption of new policy implications, and the results are shown in

Table 3. Agricultural practices before and after policy implementation.

Parameter	Category	Frequency	Percentage (%)
Used fertilizer type for paddy before the policy	CF only	238	93.7
	OF only	2	0.8
	CF and OF combination	14	5.5
Experience of using SWC for paddy	yes	36	14.2
	No (* have used for home gardening)	218	85.8
Mostly used OF type for agriculture	Straw	94	37.0
	Cow dung	22	8.6
	Poultry manure	66	26.0
	Green manure	45	17.7
	Fruit and vegetable compost	11	4.3
	SWC	16	6.3
Mode of supply on OF for paddy (after policy)	Self-preparation	137	53.9
	Purchased from the private sector	72	28.3
	Purchased from the government sector	45	17.7
Challenges in using OF for paddy	To meet the required quantity	231	91
	price	20	8
	quality	03	2

Note: * Farmers who have not used SWC for paddy were able to use it for home gardening only.

.

The results indicate that prior to the policy change, 94% of paddy farmers were utilizing CFs exclusively for their rice production, which is consistent with [23]. Among the considered OF types, straw was the most utilized OF type for agricultural purposes. Following the policy implementation, most farmers (53.9%) reported that they had to prepare the OF types themselves for paddy cultivation. An additional 28.3% of farmers procured OF from the private sector, while the government sector was the least significant supplier, with only 17.7% of farmers able to obtain OF from government entities. This situation underscores the limited availability of the required quantity OF for rice farming. Consequently, the results demonstrate that meeting the ‘required quantity’ OF was the most challenging aspect (91%) for organic paddy cultivation. To further corroborate this finding, it was observed that only 14.2% of paddy farmers were able to utilize SWC for paddy fields due to limited availability. Nevertheless, the remaining 93.7% of farmers had experience with SWC through its application in home gardening.

3.3. Farmers’ Awareness and Willingness on SWC

Table 4. Farmers’ awareness and willingness regarding solid waste compost (SWC).

Parameter	Category	Frequency	Percentage (%)
Awareness of SWC	yes	214	84.2
	no	40	15.7
Willingness to use SWC for paddy	yes	230	90.6
	no	24	9.4
(only for those who are willing to use SWC) Expected requirement related to SWC	1. government certification	145	63.0
	2. Government subsidy	80	34.8
	3. need nothing	5	2.2

Note: Percentages based on the total sample of 254 respondents.

illustrates farmers’ awareness and willingness to use SWC.

Regarding awareness, 84.2% of the paddy farmers reported being aware of SWC. Moreover, 90.6% of farmers expressed willingness to adopt SWC for their rice cultivation. Nevertheless, 97.8% of them expect the government to intervene for SWC; government certification for SWC seems to be much demanding (63%), followed by government subsidy (34.8%), while only 2.2% expect nothing.

3.4. KPI Analysis

According to the results, the mean sentiment values for the established nine KPIs in the study are presented in

Table 5. Mean sentiment values for nine key performance indicators (KPIs).

KPIs	Fertilizer Types
	Straw	Cow Dung	Poultry Manure	Green Manure	Fruit and Vegetable (F and V) Waste	SWC
Soil fertility	4.44	4.03	4.50	4.15	4.08	3.93
Soil water retention capacity	4.02	3.85	3.83	3.70	3.63	3.57
Pest–predator ratio	3.56	3.20	3.24	3.51	2.56	3.67
Weed composition	3.87	2.89	2.78	2.04	1.98	3.06
Possible health hazards in use	4.23	2.00	1.57	3.88	4.00	3.71
Price	4.05	2.09	1.54	4.16	1.74	3.90
Yield/hectare	4.11	3.81	4.59	2.48	3.00	3.08
Durability	3.82	2.41	2.25	3.25	2.22	3.31
Timely availability	3.97	1.61	2.00	3.56	3.22	1.34

Note: Scores based on a 5-point scale where 1 = Very bad and 5 = Very good.

. Paddy farmers exhibited a positive inclination towards adopting SWC as an OF supplement for their rice cultivation. SWC demonstrated superior performance in “pest–predator ratios” (mean = 3.67) compared to other OF types. Nevertheless, it exhibited poor performance in “timely availability” (mean = 1.34), aligning with [23], reflecting logistical and production challenges. Concerns about timely availability suggest logistical issues and production shortfalls. SWC might not be produced in sufficient quantities during peak planting seasons due to inadequate infrastructure, limited composting facilities, or inefficient waste collection. Distribution networks may also be underdeveloped, causing delays in semi-urban areas such as Attanagalla.

Table 6. Farmers’ comparison of SWC with other OFs.

KPI	Best Performance	SWC Value	Comparison
Soil fertility	Poultry manure (4.5)	3.93	SWC performs lower than cow dung, straw, and green manure, but it is competitive with F and V waste. Its fertility enhancement is moderate compared to organic sources such as poultry manure.
Soil water retention capacity	Straw (4.02)	3.57	SWC’s fertility enhancement is moderate compared to organic sources such as poultry manure, and competitive with F and V waste
Pest–Predator Ratio	SWC (3.67)	3.67	SWC demonstrates the highest value among all fertilizers, making it the most effective in balancing pest–predator interactions, even surpassing straw.
Weed Composition	Straw (3.87)	3.06	SWC is moderately effective in controlling weeds but underperforms compared to straw, but performs better than all other considered OFs.
Possible Health Hazards in Use	Straw (4.23)	3.71	SWC is moderately effective compared to the best performance
Price	Green manure (4.16)	3.90	Comparatively, the price of SWC is acceptable
Yield per Hectare	Poultry manure (4.59)	3.08	SWC’s yield is significantly lower than poultry manure, cow dung, and straw, competitive with F and V waste, but better than green manure, and moderate compared to other OFs.
Durability	Straw (3.82)	3.31	SWC shows good durability compared to cow dung, poultry manure, and F and V waste, but lower than that of straw
Timely Availability	Straw (3.97)	1.34	SWC significantly underperforms in availability, ranking the lowest among all fertilizer types.

Note: OF = Organic fertilizer; F and V = Fruit and vegetable.

shows the comparison of SWC with other OF types based on the considered KPIs. Accordingly, straw was the most preferred OF type for paddy among the six OF types. Farmers favored straw over SWC in certain KPIs, such as soil fertility and yield per hectare. This preference may be attributed to the accessibility and low cost of straw, a by-product of rice farming, which farmers have traditionally utilized as organic manure. SWC demonstrates moderate performance in most KPIs but excels in pest–predator ratio (3.67). Its major drawback is the timely availability (1.34), which significantly hinders its usability. While it is competitive in soil fertility and durability, SWC is less favorable regarding price and yield.

Since SWC shows a noticeable difference in timely availability with the average KPI values among the other five OFs according to Table 5, we employed the single-factor ANOVA analysis, as it allows for determining whether there is a statistically significant difference between SWC and other OFs. Accordingly, a statistically significant difference for SWC’s timely availability was observed (p value < 0.05), and this was further analyzed through a post hoc test (Bonferroni test) to pinpoint where these differences lie, and SWC showed a significant difference with all other OF types in terms of timely availability (see

Table 7. Post hoc test result (Bonferroni adjusted p value = 0.01).

Fertilizer Group	p Value
Straw-SWC	<0.01
Cow dung-SWC	<0.01
Poultry-SWC	<0.01
Green manure-SWC	<0.01
F and V compost-SWC	<0.01

).

3.5. Farmers’ Attitudes on Quality Aspects of SWC as a Supplement

Farmers’ attitudes on quality aspects of SWC as an OF supplement for paddy farming were collected through statements, using a 5-point Likert scale, and the results are summarized in

Table 8. Results of farmers’ attitudes on quality aspects of SWC as an OF supplement for paddy farming.

Statement	SDA	DA	N	A	SA	Mean Score
1. The standardization of SWC should be solely supported and supervised by the government	0	6	40	99	110	4.24
2. SWC is better applied as a mixture of other Agricultural waste for paddy farming	0	2	20	80	152	4.60
3. The addition of locally available resources, such as “glirizeediya” leaves to SWC, will increase in nutritional properties of it	9	38	50	77	80	3.71
4. Motivating farmers to cultivate “glirizeediya” leaves, buying them by LAs, and returning their benefit to farmers is a positive approach	0	8	14	98	134	4.41

Note: SDA = Strongly disagree; DA = Disagree; N = Neutral; A = Agree; SA = Strongly agree.

.

4. Discussion

We observed that 40% of paddy farmers had more than 20 years of experience in paddy cultivation, as paddy farming is a generational profession in an agricultural country such as Sri Lanka. Our findings align with [27], rice cultivation is generally considered a ‘male-dominated activity’ [28,29]. Most rice farmers tend to be 50 years of age or older, a consequence of the younger generation migrating to urban areas in search of employment opportunities, leaving agricultural activities to the older generation. However, the study’s regional focus limits the broader applicability of these demographic patterns. Regarding farmers’ awareness, Quality certification concerns impede SWC adoption, as farmers anticipate government assurance, and our findings align with the study [12], which demonstrated that quality certification significantly impacts adoption rates by increasing farmers’ confidence in product efficacy. Thus, our findings reinforce the importance of government-backed certification through quality standards.

The specific findings from Table 6 and Table 7 suggest that coordinated efforts between municipal authorities, waste management services, and agricultural supply chains are needed to ensure a consistent supply of SWC. Addressing these issues would enhance accessibility and adoption of SWC as a sustainable organic fertilizer. Government support in scaling up production and improving distribution networks would also address availability concerns and ensure timely access for farmers.

Consequently, farmers strongly agree that SWC represents an effective approach to sustainable municipal solid waste management (MSWM) in Sri Lanka; however, they emphasize that SWC standards should be exclusively maintained and supervised by the government. Moreover, farmers overwhelmingly agree that SWC is preferable for utilization in paddy cultivation in conjunction with other agricultural wastes. They are highly cognizant of SWC’s quality in terms of its nutritional properties and firmly believe that SWC must be analyzed and improved prior to its application as an organic fertilizer in rice fields. Furthermore, they posit that incorporating locally available resources into SWC, such as “glirizeediya” leaves, will enhance its nutritional value. Gliricidia sepium, commonly referred to as gliricidia, is a medium-sized leguminous tree belonging to the family Leguminosae. It is known as “wetahiriya” in Sri Lanka and is widely utilized as a shade plantation for coffee and a supportive crop for pepper cultivations, in addition to its other applications, including live fencing, firewood, green manure, intercropping, and an effective rodenticide. They also propose that this collaborative effort will incentivize farmers to cultivate “glirizeediya” leaves, purchase them from LAs, and share the benefits with farmers as an effective means to support organic farming policies.

Farmers emphasize the significance of SWC’s nutritional quality and absence of harmful substances for rice cultivation. However, nutrient variability complicates application rates, and contamination from unsorted MSW poses risks. Sri Lanka’s SWC quality is compromised using unsorted waste, which may contain trace elements, polythene, plastics, and hazardous materials. Mismanagement during composting can concentrate these contaminants, raising safety concerns for crops such as paddy, which is critical to the food chain. Ensuring waste homogeneity and improving composting processes are essential to produce safe, high-quality SWC for agricultural use.

Although SWC shows potential as an organic fertilizer according to our findings, we emphasize that attention must be given to possible contamination from heavy metals or microplastics, as highlighted in previous international experiences [30,31], underscoring the need for rigorous quality assessment and certification. Comprehensive quality analysis and alignment with global compost certification standards (e.g., FAO, ISO, or WHO guidelines) are essential to ensure environmental safety and farmer confidence.

5. Conclusions

This study aimed to evaluate the perceptions of paddy farmers in the Attanagalla Divisional Secretariat regarding SWC as a supplement for organic paddy farming that is sustainable under Sri Lanka’s organic farming policy. The findings indicate that while SWC demonstrates significant potential owing to its favorable pest–predator balance and compatibility with sustainable waste management practices, its adoption is substantially impeded by limited availability during peak seasons, followed by a lack of government-backed certification and quality compared to CFs. To address these challenges, we recommend expanding compost production with efficient distribution mechanisms and enhancing quality assurance for SWC through government-led certification is crucial. This study is limited by its regional scope, and the reliance on self-reported data introduces potential biases. Future research should explore the long-term environmental and economic impacts of SWC on farmer livelihoods in diverse agricultural settings