Sustainability Assessment of Lake Sediment-Based Soil Blocks for Agricultural Seedling Media

Abstract

The high sedimentation rate of Rawapening Lake is both an environmental challenge and a potential resource. Seedlings currently rely on single-use plastic polybags, which contribute significantly to plastic waste. The use of mineral soil as a growing medium can accelerate natural resource depletion. This study aims to evaluate the feasibility and sustainability of utilizing lake sediment as an alternative seedling media through soil block technology. An integrated Life Cycle Assessment was conducted to quantify the environmental impacts, and Multidimensional Scaling was applied to assess sustainability across environmental, technological, economic, social, and institutional dimensions. Field data from ten seedling producers using soil blocks and ten using polybags were analyzed. The results showed that soil block media reduced Global Warming Potential by 48% compared to polybags, increased phosphorus and organic matter content, and was more financially efficient, with an increase in productivity of 90.24% and a revenue cost ratio of 24.56%. Sustainability analysis classified the innovation as moderately sustainable, with the highest scores in the environmental and technological dimensions. Institutional support was identified as a limiting factor. These findings suggest that sediment-based soil block media are a viable, lower-impact alternative for seedling production, although scaling up will require policy and institutional support.

1. Introduction

The rapid sedimentation of Rawapening Lake, located in Central Java, Indonesia, has become a critical environmental concern, threatening the lake’s ecological stability and reducing its functional capacity [1]. This sedimentation is largely driven by watershed erosion and compounded by the decay of invasive water hyacinths, which release peat and organic matter into the lake [2,3,4]. The accumulation of sediments not only degrades aquatic ecosystems but also hampers the lake’s economic and ecological services, including fisheries, tourism, and agricultural water supply [5]. Simultaneously, agricultural nursery practices in Indonesia remain heavily reliant on plastic polybags and mineral soils, contributing to over 500,000 kg of plastic waste annually and exacerbating land degradation through excessive soil extraction [6,7]. These dual environmental issues, lake sedimentation and unsustainable nursery practices, highlight the urgent need for innovative, circular, and sustainable solutions in agriculture [8].

Reducing Global Warming Potential (GWP) is a growing concern in agricultural sustainability, especially in nursery systems where plastic containers and peat-based media are major contributors to greenhouse gas emissions. Recent Life Cycle Assessment (LCA) studies have demonstrated that replacing plastic pots and conventional substrates with composted or sediment-based media can reduce CO₂-equivalent emissions by up to 23% [9,10]. Biochar and sediment-based soil blocks have also been shown to improve water retention and soil health while lowering greenhouse gas (GHG) footprints in nurseries [11]. These findings emphasize the need to evaluate sustainable alternatives using robust environmental indicators such as GWP.

Previous studies have explored the utilization of organic waste and alternative growing media in soilless agriculture and seedling production, with soil block technology gaining traction in Western countries since the 1970s [12,13]. Soil blocks, composed of compressed organic materials such as cocopeat, manure, and compost, have shown advantages in improving seedling quality, root development, and transplant success [14,15]. In tropical regions, the use of invasive water hyacinth and lake sediments has also been considered as agricultural inputs due to their high nutrient content and soil-enhancing properties [4,16].

Lake sediments, especially those from eutrophic tropical lakes, are often rich in macronutrients such as phosphorus (P) and nitrogen (N), as well as organic matter that can improve soil structure and nutrient availability. For example, field studies using lake sediments in Estonia reported P concentrations of up to 75 g/m³ more than three times that of surrounding soils and improved plant biomass [17]. Similarly, experiments in Poland and China found that sediment amendments enhanced plant growth and nutrient uptake, although careful management is needed to mitigate potential risks such as nutrient leaching or heavy metal accumulation [18,19,20]. When combined with stabilizing agents such as biochar, sediment-based media can provide both agronomic benefits and environmental safety [21].

However, most of these efforts have focused narrowly on technical or environmental aspects without a comprehensive evaluation of the long-term feasibility, economic viability, and social acceptance of such technologies, particularly in developing countries like Indonesia [22,23]. Despite these advancements, there remains a significant gap in the literature regarding the holistic evaluation of soil block technology, particularly those utilizing lake sediments as the primary growing media. Prior studies have not adequately assessed the environmental trade-offs, socio-economic benefits, or institutional challenges associated with the adoption of soil blocks in real agricultural systems [24,25]. Furthermore, the integration of comprehensive tools such as LCA for quantifying environmental impacts and Multidimensional Scaling (MDS) for evaluating sustainability across multiple dimensions has yet to be applied in this context [26,27].

This study addresses these research gaps by investigating the multidimensional feasibility of using Rawapening Lake sediment as a core component of soil block seedling media. Specifically, it aims to (1) assess the environmental, technological, and economic performance of soil block media in comparison with conventional polybag-based systems using LCA; and (2) evaluate the sustainability of the soil block media across five dimensions environmental, technological, economic, social, and institutional using MDS [28,29]. The novelty of this research lies in its integrated methodological approach and its focus on utilizing locally sourced agricultural and aquatic waste materials as part of a circular economy model for sustainable nursery practices [30,31].

The findings of this study are expected to provide empirical evidence supporting the reuse of lake sediments as a sustainable innovation in seedling media production. This approach contributes not only to environmental impact reduction through lower greenhouse gas emissions and plastic waste reduction but also to enhanced agricultural input efficiency and improved circular resource management [32,33]. In doing so, this research informs future agricultural policy, patent development, and institutional strategies necessary to scale up soil block technology within Indonesia and in other regions facing similar environmental and agricultural challenges [34,35].

2. Materials and Methods

2.1. Description of Study Area

The research locations, including the Wonosobo and Magelang Regencies in Central Java, Indonesia, were selected purposively. These areas were chosen because of the established seedling businesses employing the soil block method with Rawapening Lake sediment media. In the Wonosobo Regency, a soil block maker was utilized, whereas in the Magelang Regency, the soil block was manually produced.

The raw materials for the soil block formulation in Wonosobo were a combination of Rawapening Lake sediment, cocopeat, poultry manure, agricultural lime, and natural phosphate. The raw materials used to formulate the Magelang soil block were a combination of topsoil, Rawapening Lake sediment, and poultry manure. The raw materials used for soil block at research sites, namely Rawapening Lake sediment, cocopeat, and poultry manure, had different chemical characteristics (

Table 1. Chemical characteristics of Rawapening Lake sediment, cocopeat, and poultry manure.

Raw Material	Parameter
	pH	Carbon Organic (%)		Total Nitrogen	Total Phosphorus	Available Phos Phorus	Total Potassium	Available Potassium	CEC
		Carbon Content	OM Content	(%)	ppm	ppm	ppm	ppm	cmol/kg
Original Rawapening Lake sediment	6.16	56.14	96.79	2.12	512.43	101.09	2.32	0.73	46.9
Cocopeat	7.11	46.72	80.55	0.82	455.33	37.35	35.34	-	-
Poultry manure	7.8	20.84	35.94	3.13	1987.99	244.34	186.21	-	-

Note: pH: Potential of Hydrogen; OM: Organic Matter; ppm: Parts Per Million; CEC: Cation Exchange Capacity.

).

Rawapening Lake sediment is derived from the in situ decay of invasive water hyacinths and the accumulation of organic matter. As a result, it contains elevated levels of organic carbon, nitrogen, phosphorus, and humic substances, which act as slow-release nutrient pools that are favorable for plant growth [36,37]. When blended with cocopeat, a lignocellulosic material with high porosity and water-holding capacity, the mixture creates a physically optimal environment that facilitates root expansion and aeration [38]. Poultry manure provides a source of rapidly mineralizable nutrients, especially N and P, and introduces beneficial microbial consortia that accelerate organic matter decomposition and nutrient mineralization [39,40]. This combination enhances the physical, chemical, and biological properties of seedling substrates. Sediment supplies baseline macro- and micronutrients with buffering capacity, cocopeat improves moisture retention and structural stability, and poultry manure boosts nutrient turnover via microbial stimulation. The synergy among these components leads to increased cation exchange capacity (CEC), sustained nutrient availability, and enhanced seedling vigor, which collectively explain why this mixture outperforms conventional mineral soil plus fertilizer combinations, which often lack a balanced structure or consistent nutrient release [6,40].

The research samples were strategically chosen through purposive sampling, comprising ten seedling producers who utilized soil blocks and ten conventional seedling producers. Additional respondents included Rawapening Lake sediment media providers, practitioners, researchers, and policymakers who underwent in-depth interviews. In-depth interviews with respondents were conducted in October and November 2023 to collect primary data. The interview tool was a structured questionnaire containing questions that assessed respondents’ evaluations of attributes across various sustainability dimensions, including environmental, technological, economic, social, and institutional.

2.2. Life Cycle Inventory

As outlined in the preceding section, sediment from Rawapening Lake has the potential to be used as a seedling media. Its utilization is combined with several other components such as biomass waste, cocopeat and livestock waste as sources of nutrients for plant growth. To evaluate the environmental benefits of using soil blocks compared to traditional polybags, LCA was conducted. LCA is a widely known method for evaluating the environmental impact of a product and the processes involved in making the product [26,41]. This methodology offers a clear and transparent framework for calculating the flow of materials and energy, as well as the environmental impacts associated with each stage of a product’s life cycle. In this study, LCA will be applied to assess the environmental impacts of producing soil blocks made from Rawapening sediment. The analysis will cover the entire life cycle of the process, including stages such as sediment collection, until they are ready to be moved to the field. Specifically, the cradle-to-gate approach will be used. The aim is to identify the GWP of the production of soil blocks and polybag seedling media that are ready to be used in the nursery of one-piece soil blocks as a reference. The boundary is the production process of soil blocks and polybag seedling media to produce planting media used for one-piece soil blocks.

2.3. Variable Selection for Multidimensional Analysis

A total of 34 attributes from all dimensions in the MDS analysis were selected through a two-stage process: first, a comprehensive literature review was conducted to compile a list of potential sustainability indicators; second, validation with in-depth interviews and discussion with key local stakeholders was carried out to ensure contextual relevance at the research site (

Table 2. Variable dimensions and attributes of multidimensional analysis.

Variables Dimension	Attributes
Environment	Reduction in pollution from plastic polybags
	Reduction in sedimentation damage
	The potential of agricultural biomass waste utilization
	Mineral soil exploitation decreases
	Water irrigation used efficiency
	The potential of pesticide reduction.
Technology	Media mixture access and availability
	Sediment media access and availability
	Soil block formulation preparation is easy
	Effect of soil block media on seed germination and growth
	Time and cost savings from soil block technology
	Production increases from soil block technology
	Product quality improvement from soil block technology
	Production stability opportunity with soil block technology across seasons
Economics	Production and labor cost reduction
	Potential market of seedling media
	Price of seedling media
	Capital access
	Input production access
	Income increases opportunities
Social	Acceptance of soil block technology among business actors
	Labor absorption increases in Rawapening
	Labor absorption boosts in vegetable seedling centers
	Women’s Involvement Enhancement
	Family welfare improvement opportunities
	New business creation prospects
	Community resilience augmentation potential
	Growth in community awareness
Institutional	Institutional support enhances marketing of soil block seedling media
	Institutions facilitate capital access for soil block seedling media development
	Institutional support for the sustainability of the soil block seedling media business
	Government support fosters soil block seedling media development
	Private sector involvement supports soil block seedling media development
	Existing institutions enhance production input accessibility

). Each attribute was assessed using four ordinal categories: 0 = Bad, 1 = Less, 2 = Fairly, and 3 = Good. All attributes were treated with equal weight, in accordance with the standard Rapfish, which emphasizes exploration leverage factor identification. To validate the robustness of the MDS results and reduce the risk of subjectivity of attribute selection, a Monte Carlo simulation and stress test were applied.

2.4. Analytical Methods

The performance analysis aimed to assess the advantages of soil block technology for seedling media composed of Rawapening Lake sediment. The performance is based on three advantages: (i) soil block technology suppressing GWP (environmental), (ii) the nutrient content of soil block seedling media (technological), and (iii) the economic feasibility of soil block seedling media (economic).

The environmental performance of soil blocks as seedling media was obtained by LCA comparing the production processes of polybags. OpenLCA 2.02 software was used for the analysis along with the Ecoinvent 3.8 database (Swiss Centre for Life Cycle Inventories, 2018). The life cycle inventory (LCI), which contains comprehensive inventory data for various processes, including those related to agriculture and waste management, will be applied to this database. Life Cycle Impact Assessment (LCIA) was conducted using the Centrum voor Milieukunde Leiden (CIML) midpoints impact method to obtain the GWP of the two-seedling media.

The technological performance of the nutrient content of seedling media was assessed by comparing seedling media produced in Wonosobo (using soil block equipment) and Magelang (manually). The nutrient content of seedling media was analyzed in a soil laboratory at the Agricultural Faculty of Muhammadiyah Yogyakarta University, including pH, organic carbon, organic matter (OM), total nitrogen (N), total and available phosphorus (P), and total and available potassium (K).

The economic performance of business feasibility to assess business efficiency was evaluated by financial analysis in a life cycle production process of polybag seedling media compared to that of soil blocks. Financial feasibility analysis shows the feasibility of a farm by using input–output or production facilities as well as its labor requirements, as conducted by Krisdiana et al. [42] using basic measurements such as production costs, labor wages, income, profit, revenue to cost ratio (R/C), and marginal benefit cost ratio (MBCR). Higher R/C values reflect the efficiency of resource and production input use [43]. MBCR > 1 indicates that the implementation of new technology increases efficiency because it generates a higher profit value than the value of the costs sacrificed [42].

Data on production capacity and unit cost per tray were collected from primary sources through structured field observations and interviews with seedling producers in Wonosobo between October and November 2023. The production capacity for both the soil block and polybag systems was calculated based on actual work performance during a standard 7 h workday. Cost components were compiled from documented input–output records and further verified through semi-structured interviews with the same seedling producers.

Sustainability was analyzed using MDS. MDS is a method for representing the measurement of similarity or proximity between objects, which can be individuals, attributes, regions, countries, products, and others, and is visualized as a two-dimensional graph [44]. The analysis in this study was carried out using the “Rapid Appraisal Technique for Fisheries” (RAPFISH) version 3.1, adapted to the RAPsoilblock ordinance technique. Adaptations were made to refine and align the attributes within each sustainability dimension to suit the research context and scope of this study [27]. MDS computations were based on the Euclidean distance matrix technique, as prescribed by Mancell and Deutsch [28]:

$$d_{\mathrm{1,2}}= \sqrt{{\left(X_1-X_2\right)}^2+ {\left(Y_1-Y_2\right)}^2+{\left(Z_1-Z_2\right)}^2+\cdots }$$

(1)

Notes:

$d_{\mathrm{1,2}}$ = Euclidean distances.

X,Y,Z = Attributes.

1, 2 = Observation.

RAPFISH applied the Alternating Least Squares Scaling (ALSCAL) algorithm for iterative processes aimed at obtaining the smallest error value, thereby setting the intercept to zero (a = 0):

d₁₂ = bD₁₂ + e

(2)

The iterative process halts when the stress value falls below 0.25; therefore, the model is considered viable if the stress level is under 0.25:

$$Stress= \sqrt{{\displaystyle \frac{1}{m}}\sum _{k=1}^m\left[{\displaystyle \frac{{\mathsf{\Sigma }}_i{\mathsf{\Sigma }}_j{\left(D_{ijk}-d_{ijk}\right)}^2}{{\mathsf{\Sigma }}_i{\mathsf{\Sigma }}_j{d}_{ijk}^2}}\right]}$$

(3)

The results of the sustainability index analysis are categorized into four levels: unsustainable (0.00–25.00), less sustainable (>25.01–50.00), moderately sustainable (>50.01–75.00), and highly sustainable (>75.01–100.00) [29]. The attribute leverage evaluation was utilized to determine the most sensitive attributes concerning sustainability. Attributes with higher values contributed significantly to sustainability by affecting the “Root Mean Square” (RMS) changes along the X-axis. The greater the RMS change, the more sensitive the indicator’s role in enhancing sustainability status [45]. According to Darwis et al. [46], the “Stress and Squared Correlation” (RSQ) or R² values indicated the level of precision in the analysis or the “goodness of fit”. A model was considered good if the stress value < 0.25 (approaching 0). “The stress and coefficient of determination” (R²) values indicate the quality of the generated model (goodness of fit). An R² value is considered good if it is close to one. Monte Carlo simulation was used in MDS to assess robustness under data variability and validate that the dimensional structure is not due to random chance. With a 95% confidence interval, the simulation showed minimal differences Δ < 5% between MDS original and Monte Carlo simulated sustainability indices, indicating that the MDS configuration is stable and the results are statistically reliable.

3. Results and Discussion

3.1. Performance of Soil Block Technology for Seedling Media

3.1.1. Life Cycle Analysis of Soil Block Technology Suppressing Global Warming Potential

The inventory data of the seedling media used for the single seed was obtained in accordance with the field observations (

Table 3. Life Cycle Assessment inventory of seedling media for single-seed applications.

Data Inventory	Unit	Value
		Polybag	Soil Block
Size	cm3	30	27
Fuel (Diesel)	L	0.000025	-
Fuel (Petrol, unleaded)	L	-	0.0000135
Fertilizer (Super Phosphate 36TM) *	g	0.064	-
Cocopeat	g	-	5.91
Dolomite	g	-	0.985
Rock Phosphate	g		0.985
Water	L	-	0.0122
Plastic Polybag	g	0.065	-
Pesticides	g	0.0015	0.00068
Insecticides	g	0.00135	0.00061
Manure	g	8.856	5.91
Sediment	g	2.952	5.91

Note: * Super Phosphate 36^TM produced by PT. Petrokimia Gresik, Indonesia.

). The life cycle inventory analysis of the two-seedling media (polybag and soil block) revealed notable differences in terms of material composition, energy consumption, and resource utilization, each reflecting a distinct environmental footprint. The units presented in Table 3 refer to either mass (gram) or volume (cm³ and liter), indicating the amount of each material used per single seedling. The polybag media, with a volume of 30 cm³, is characterized by a high reliance on synthetic substances and fossil-derived inputs. It incorporates diesel fuel, synthetic fertilizer SP-36, and plastic polybags, highlighting its dependence on nonrenewable resources. Additionally, it contains a lower proportion of organic materials, including manure and lake sediment, than the soil block.

Conversely, the soil block media prioritizes the use of natural and biodegradable components. It uses a smaller amount of unleaded petrol for energy input and entirely omits synthetic fertilizers. Instead, the media consists of cocopeat, dolomite, and rock phosphate, along with a greater quantity of lake sediment, reinforcing its environmentally sustainable design. Water usage is minimal, and the exclusion of plastic materials further supports waste minimization.

Furthermore, the soil block media requires fewer chemical plant protection substances and utilizes smaller quantities of pesticides and insecticides than the polybag media. Although both media incorporated organic manure, the soil block contained a smaller amount, potentially compensated for by nutrient contributions from sediment and mineral additives.

In this study, GWP was selected as the primary indicator for environmental impact assessment because GWP is one of the most widely applied impact categories in the LCA approach [47], particularly because of its relevance to global climate change, which remains a central focus of international agreements such as the Paris Agreement and national sustainability agendas [48]. And, GWP is a requirement for assessing the company’s performance rating in environmental management carried out by the Indonesian Ministry of Environment and Forestry. Based on the life cycle inventory, the GWP of soil blocks and polybag seedling media production was calculated (Figure 1).

The figure shows that the production of polybag seedling media has a higher GWP value than that of soil block media. This is primarily due to the inclusion of plastics, which have a high carbon footprint and contribute substantially to GHG emissions. According to Haase et al. [6], polybags, typically made of High-Density Polyethylene (HDPE) plastic, generate large amounts of waste and have major environmental impacts, especially because they are designed for single uses [7]. Furthermore, the use of polybags (especially the commonly used black plastic types in nurseries) can lead to substantial fluctuations in soil surface temperature. Young and Hammett [49] reported that the use of polybags increases soil temperature up to 49–50 °C due to their high heat absorption and low reflectivity when exposed to direct sunlight. Therefore, additional inorganic fertilizers are required in the planting media [50]. Replacing polybags with alternatives like soil blocks could not only reduce plastic waste but also create a more thermally stable environment for healthy seedling growth.

In contrast, soil block media has emerged as a more sustainable alternative owing to its use of renewable and biodegradable inputs, absence of plastic packaging, and lower dependence on agrochemicals. These results align well with the goals of sustainable agricultural practices, which aim to reduce waste, conserve resources, and minimize environmental harm. The results of this LCA indicate that soil blocks made with locally sourced and biodegradable materials offer a significantly lower environmental impact, contributing to more sustainable farming practices.

The results of LCA calculations related to GHG emissions from the use of soil blocks present promising opportunities for sustainable development. Sediment is often considered as waste and the transition to sediment-based seedling media aims to reduce GHG emissions, with a range of GHG emission reductions of 48% when compared to polybags. In addition, soil blocks contain essential nutrients and organic matter that can improve soil structure and fertility, thus supporting strong plant growth while reducing the need for chemical fertilizers that contribute to GHG emissions [51]. The use of fertilizers is an important aspect because it shows the potential of soil block sediment as a resource that can contribute to reducing the depletion of natural resources by substituting chemical fertilizers. Thus, sedimentation seedling media is a multifaceted strategy that can contribute significantly to reducing the environmental footprint of agriculture while encouraging resilience to climate change.

Greenhouse gas emissions play a significant role in influencing soil erosion and biodiversity dynamics. The mechanisms by which GHG emissions influence soil erosion and biodiversity are related to the physical properties of the soil and its biological activity. Climate change, exacerbated by increased GHG emissions, leads to changes in precipitation patterns, soil moisture, and temperature, all of which can accelerate soil erosion [52]. Soil biodiversity is highly dependent on stable conditions, as GHG emissions cause climate disruptions, resulting in the decline of soil organisms vital to soil health and function [53]. Changes in GHG levels can alter nutrient cycling and the decomposition of organic matter, which sustain soil microorganisms, thereby impacting broader biodiversity within the ecosystem [54].

To further explore the environmental impacts of soil blocks as seedling media, future studies should expand the LCA scope to include additional impact categories beyond GWP, such as acidification, eutrophication, water consumption, and biodiversity loss. This would allow for a more comprehensive and detailed evaluation of the environmental trade-offs associated with soil block production and the reuse of lake sediments as seedling media.

3.1.2. Potential Nutrient-Rich Content of Soil Block Seedling Media Based on Rawapening Lake Sediment

The media analysis revealed that the Wonosobo and Magelang soil block seedling media formulation contained higher levels of essential nutrients across all parameters, including pH, organic carbon, organic matter, total and available phosphorus, and total and available potassium, than mineral soil media (

Table 4. Chemical characteristics of seedling media of Rawapening Lake sediment.

No	Media Type	Parameters
		pH	C Organic (%)		Total Nitrogen	Total Phosphorus	Available Phosphorus	Total Potassium	Available Potassium	CEC
			Carbon Content	OM Content	(%)	ppm	ppm	ppm	ppm	cmol/kg
1	Wonosobo soil block media *	7.15	34.97	60.30	1.11	1580.07	155.39	85.34	522.91	38.50
2	Magelang soil block media **	6.67	9.84	16.97	0.31	393.90	18.91	43.79	10.11	12.00
3	Mineral soil media	7.14	3.65	6.29	0.20	142.83	23.47	48.45	34.90	11.45

Note: * Wonosobo soil block media consists of Rawapening Lake sediment, cocopeat, poultry manure, dolomite, and natural phosphate. ** Seedling media with polybags consist of sandy soil, Rawapening Lake sediment, and poultry manure.

).

The term mineral soil media in this study refers to naturally occurring soil materials composed primarily of inorganic mineral particles such as volcanic, alluvial, or entisol soils that are commonly used in horticultural nurseries in Central Java. These soils are rich in sand, silt, and clay minerals but contain low levels of organic matter. They are typically sourced through topsoil extraction in agricultural or riverine areas and widely applied as conventional substrates in seedling production [55,56]. In this experiment, mineral soil was obtained from a local horticultural nursery supplier in Wonosobo Regency, which routinely collects topsoil from nearby agricultural areas for commercial seedling propagation. The soil was air-dried, sieved (2 mm), and mixed with organic fertilizer (chicken manure) according to common local nursery practices [57]. This soil served as the control treatment to compare with the sediment-based soil block formulations.

Among the three-seedling media, Wonosobo seedling media with a mixture of Rawapening Lake sediment, cocopeat, and chicken manure had a higher chemical content than Magelang soil blocks or mineral soil media. Sediments in the form of peat have good chemical characteristics such as seedling media because of the high content of organic matter and other elements good for seed growth, and they have physical characteristics that are light but able to bind high amounts of water [15,58]. According to the research results of Gowthami et al. [59], cocopeat is a commonly used media seedling raw material because of its chemical content that is suitable for seed growth, namely, its higher levels of total N, total P, total K, and organic carbon compared to soil media. Organic manure plays an important role in seedling media because it contains high levels of organic C and other chemicals that are important for seed growth [15].

In addition, the use of biomass waste reduces dependence on mineral soils, which can have a negative impact on the environment when used in large quantities. This approach supports sustainable agriculture by recycling waste materials and reducing the need for new soil extractions. The use of sediment–organic waste mixtures can improve soil properties, such as CEC and pH balance, which are essential for optimal plant growth. These mixtures also have a minimal risk of metal mobility, making them safe for agricultural use [58]. Utilization of residual biomass can lead to a more environmentally friendly agricultural system [60].

This shows that seedling media containing a mixture of biomass wastes were of better quality than media with mineral soil as the main component (

Table 5. The economic feasibility of soil block seedling media.

No	Description	The Media of Polybag	The Media of Soil Block	Efficiency
1.	Production capacity of 1 person working day in 8 h (tray/man-day)	8.00	82.00	(+) 90.24%
2.	Production cost (IDR/tray)	14,550.00	10,961.00	(−) 24.67%
	a. Raw material (IDR/tray)	9450.00	8961.00	(−) 5.17%
	b. Labor wages (IDR/tray)	5100.00	2000.00	(−) 60.78%
3.	Total cost (IDR)	116,400.00	898,802.00
4.	Price (IDR/tray)	25,000.00	25,000.00
5.	Revenue (IDR) (1 × 4)	200,000.00	2,050,000.00	(+) 90.24%
6.	Benefit (IDR) (5–3)	83,600.00	1,151,198.00	(+) 92.74%
7.	R/C (5/3)	1.72	2.28	(+) 24.56%
8.	MBCR		1.36

Note: IDR: Indonesian Rupiah. Source: primary data, 2024.

). The superior characteristics of the seedling media composed of Rawapening Lake sediment show that, technologically, the right mixture of biomass waste can be a promising seedling media technology for the seedling industry, which is more profitable for environmentally friendly agricultural activities.

3.1.3. The Economic Feasibility of Soil Block Seedling Media Business Based on Rawapening Lake Sediment

The implementation of soil block technology in the production of seedling media has been shown to enhance labor productivity by 90.24% (Table 5). This substantial increase in production capacity is attributable to improved resource utilization, whereby identical time inputs yield significantly higher output volumes. These findings are consistent with those of Goswami and Daultani [61], who emphasize that operational efficiency and strategic application of appropriate technologies are critical pathways for optimizing production capacity. Furthermore, the present study demonstrates that the adoption of soil block molding technology can lead to a 90.24% increase in revenue and a 92.74% increase in producer profitability, underscoring its potential as an effective tool for enhancing the economic performance of seedling production systems.

The production of seedling media using soil block technology reduced the production cost by IDR 3589, representing a 24.67% increase in cost efficiency. This cost efficiency is primarily driven by the optimization of labor wages, which contributes 60.78% to the overall reduction. Production efficiency in enterprises is influenced by many factors, with labor wage optimization being the most dominant [62]. Soil block seedling media is also more feasible, as indicated by a higher R/C of 2.28 compared to 1.72 for polybag media. Although both methods are financially viable, the soil block method is 24.56% more cost-efficient than the polybag method [43]. The soil block seedling business also exhibits a MBCR of 1.36, meaning that for every additional IDR 1 invested due to the adoption of the technology, an additional return of IDR 1.36 is generated. The implementation of soil block technology increases costs by IDR 782,402 but simultaneously raises revenue by IDR 1,151,198, resulting in a net benefit of IDR 285,196. Several studies have reported MBCR values greater than 1, indicating enhanced efficiency and financial feasibility of the production process [63,64].

Soil block technology offers significant economic and productivity advantages for vegetable seedling production. Its application can increase output from 8 to 82 trays per worker per day (7 h), over ten times higher than plastic polybags. Production costs per tray are reduced by 24.7%, from IDR 14,550 to IDR 10,961. On a 10,000-hectare scale, this translates to a 19.29% cost saving and a 43.94% increase in net profit, highlighting its potential for sustainable, large-scale adoption.

Importantly, soil block seedlings are sold at similar prices to those grown in polybags, meaning no additional cost burden for farmers. Therefore, the key to wider adoption lies in farmer training and outreach on the benefits of this technology [65].

A major challenge is ensuring sustainable access to raw materials such as sediment and cocopeat. This requires investment in processing equipment by growing media enterprises and access to soil block machinery for farmers. Institutional support through subsidies, partnerships, or cooperative-based procurement is essential to enable collective and long-term adoption.

Performance analysis confirmed that the soil block seedling media outperformed polybag-based media across environmental, technological, and economic dimensions. However, despite its development since 2017, the downstream adoption of soil block technology is yet to replace polybag systems. The current analysis remains partial in scope; thus, further investigation of other influencing dimensions, including social and institutional factors is required to comprehensively understand the adoption barriers. A multidimensional analysis is crucial for holistically assessing sustainability and identifying the key factors that drive performance across all five dimensions.

3.2. Sustainability of Soil Block Seedling Media Business: A Multidimensional Approach

3.2.1. Sustainability and Validity Models

The results of the sustainability index indicate that the environmental, technological, economic, and social dimensions are considered ‘moderately sustainable’, whereas the institutional dimension remains in the ‘less sustainable’ category. Among these dimensions, the environmental dimension exhibits the highest index value at 73.22, whereas the institutional dimension ranks the lowest at 36.96 (

Table 6. Sustainability assessment scores by dimension.

Dimension	Sustainability Indeks	Stres Value	R2	Monte Carlo Indeks	Diferences	Category of Sustainability
Environment	73.22	0.15	0.94	73.32	0.10	Enough (moderately sustainable)
Technology	65.11	0.15	0.95	64.95	0.16	Enough (moderately sustainable)
Economics	62.62	0.16	0.94	63.14	0.52	Enough (moderately sustainable)
Social	60.60	0.15	0.95	60.41	0.19	Enough (moderately sustainable)
Institution	36.96	0.15	0.94	37.27	0.31	Less (less sustainable)
Mean	59.70	0.15	0.94	59.82		Enough (moderately sustainable)

). The sustainability level of the seedling media soil block based on the Rawapening Lake sediment falls within the “moderately sustainable” category (59.70).

The MDS configuration produced a stress value ranging from 0.15 to 0.16 (stress < 0.25) and an R² value between 0.94 and 0.95 (close to 1), indicating a good model fit with high reliability in representing the multidimensional sustainability attributes and accurately reflecting the input data. Monte Carlo simulation was used to test the robustness of the MDS results. The differences between original and Monte Carlo simulated sustainability indices were all below the Δ < 5% threshold, ranging from 0.10 to 0.52. This indicates that the MDS configuration is generally stable and reliable under data variation. Slightly higher deviations in the social and institutional dimensions suggest greater variability in perception, but overall, the results confirm the consistency and validity of the dimensional structure.

The technology employed in this study prioritizes environmentally friendly practices that utilize waste materials from local sources, initially of low economic value, and transforms them into higher-value products. The utilization of Rawapening Lake sediment waste from erosion, cocopeat from coconut waste, and organic fertilizer from animal manure waste, as well as the minimization of plastic polybag and mineral soil usage, highlight why the environmental dimension in this study exhibited the highest sustainability index compared to other dimensions. Over the past few decades, many industries have recognized the critical importance of the environmental dimension in sustainability. As a result, they have incorporated ‘key environmental value drivers’ in their business strategies, thereby enhancing product value at the consumer level [66].

3.2.2. Environmental Dimension

In the leverage evaluation of the six attributes comprising the environmental dimension, three attributes stand out as particularly sensitive, namely, the potential of agricultural biomass waste utilization, a reduction in pollution from plastic polybags, and a decrease in mineral soil or mineral soil exploitation, with respective RMS values of 5.73, 4.62, and 4.44 (Figure 2).

Environmental sustainability in this study was supported by the utilization of locally available agricultural biomass waste. The soil block formulation consists of Rawapening Lake sediment, cocopeat, and poultry manure materials abundant near the study site. Converting this biomass into soil blocks not only reduces the environmental impact but also adds economic value by producing high-quality seedling media. Rawapening Lake generates substantial sediment annually, as stated by Nugroho [67].

Hristov et al. [66] report 501,628.6 tons and Sadewo et al. [68] report 2350.44 tons from the sub-watershed alone. This abundant sediment supply offers significant potential as a raw material for soil blocks, supporting both environmental management and sustainable resource utilization in the lake area. Rawapening Lake sediment has been shown to improve soil attributes, influence microbial activities, enhance plant growth, and positively affect the nutrition of vegetable plants [69]. Sediments have a richer nutrient content and a different particle composition than regular soil (Table 2), making sediment usage more advantageous [13].

The reduction in pollution from plastic polybags is the second most significant factor impacting the sustainability of the environment. Roeswitawati et al. [70] mentioned that organic media made from water hyacinth and coconut fiber, combined with goat manure, produced the best results, as evidenced by plant height, leaf count, flower count, and fruit count parameters. The substantial use of container-less seedling media can also effectively decrease polybag usage [71], provide a more sustainable and environmentally friendly planting alternative [72], promote better seedling growth, and offer more environmentally friendly benefits [73].

The third most influential factor impacting the sustainability of the environmental dimension was the reduction in mineral soil exploitation. The utilization of sediment waste in soil block media provides a sustainable solution for reducing the environmental damage caused by mineral soil excavation [74,75]. Utilizing lake sediment as a substitute for mineral soil in soil block production offers a sustainable alternative that enhances soil fertility, moisture retention, and porosity, potentially improving crop productivity [76,77]. Additionally, the use of sediment, cocopeat, and organic fertilizer can create sustainable mineral soil-free soil block media [78], reduce heavy metal contamination, and support environmentally friendly farming practices [58]. Excessive mineral soil use, particularly with agrochemicals, tillage, and improper machinery, leads to erosion, nutrient loss, and declining soil organic carbon, ultimately reducing soil health and yield [79,80].

The use of soil blocks offers a sustainable alternative to plastic polybags, as supported by both MDS (RMS = 4.62) and LCA results, which show a substantial reduction in GWP due to minimized plastic production and waste. The results from the MDS analysis were aligned with the findings from the LCA results. LCA clearly indicates that the use of Rawapening Lake sediment in soil block production significantly reduces GWP compared to conventional seedling media, and this supports the high sensitivity observed in the MDS analysis for factors such as biomass waste utilization, plastic polybag pollution reduction, and mineral soil exploitation reduction. The LCA results further highlight that soil blocks contribute to environmental sustainability by avoiding the use of plastics and reducing dependency on synthetic fertilizers. This alignment confirms that both MDS and LCA emphasize the importance of utilizing local resources and minimizing environmental harm to enhance the sustainability of agricultural practices.

3.2.3. Technological Dimension

In the leverage evaluation of the eight attributes comprising the technological dimension, three attributes stand out as sensitive to the sustainability of nursery businesses—time and cost savings, increasing growing media production capacity, and ease of formulation and preparation—with RMS values of 2.69, 1.51, and 1.28, respectively (Figure 3). The soil block method for seedling media stands out as the most critical attribute in the technological dimension, offering significant time and cost efficiency. Time and cost savings are among the most important attributes of sustainability in a business, as they directly affect efficiency and the price of seeds per unit. Cheaper seed prices increase product competitiveness, making them easier to market.

One of the key characteristics of the technical dimension is the ease with which the soil block seedling media can be prepared. This quality is strongly tied to two other essential attributes: the first is that using soil block technology saves time and money, and the second is that it increases the production of seedling media. These characteristics are closely associated and help achieve moderately sustainable values in sustainability analysis. From the results of in-depth interviews with seedling media business actors, it is known that the production process of soil block media is simpler because it only requires two stages: first, mixing raw materials according to the composition, and second, making soil blocks using a soil block maker, producing 91 blocks in one process, with the results being directly arranged in wooden trays. Meanwhile, the production method of seedling media with plastic polybags goes through three stages: first mixing the raw materials and then putting the media mixture into plastic polybags one by one, followed by arranging the plastic media one by one into wooden trays. Therefore, soil block technology for seedling media saves time and labor and increases production because, in the same amount of time, more soil block media is produced compared to polybag seedling media.

As an illustration, using a soil block maker, one worker can produce 8800 seedling media, whereas conventional plastic methods can only yield 4200 seedling media per day (eight working hours). Using a soil block maker increases the technical performance by 109% compared to conventional methods. This demonstrates that technology can save time and labor. The use of a soil block maker also enhances economic performance. The production cost per unit of seedling media using the sediment-based Rawapening soil block method was 50% more efficient than conventional methods. Research by Haase et al. [6] indicated that nursery management with soilless technology and using insulated containers without polybags is more efficient in terms of time use when compared to the nursery process using plastic polybags.

Another benefit of soil block technology is its nutritional value. Soil blocks have excellent nutrient content to support seed growth during seeding and after transplanting to the fields. Comparative analysis showed that soil blocks without mineral soil contained higher macronutrient levels without additional inorganic fertilizers, unlike mineral soil-based media, which require nutrient supplementation (Table 5). According to Grossnickle and MacDonald [81], seedlings grown in media with optimal nutrient reserves can enhance shoot growth after transplanting. Seedling growth is a crucial factor influencing crop production [82], and the increased production of some crops is generally followed by increased farmer income [83]. According to Fuentes-Peñailillo et al. [84], healthy seedling growth supports plant growth and development in the subsequent field phase, thus enabling plants to achieve maximum production. As Gruda [85] stated, soilless seedling technology can improve water use efficiency because peat sediment has high water retention capabilities. Moreover, Rawapening Lake sediment is a readily available natural waste that must be removed from the lake to prevent worsening sedimentation [86]. Based on the explanations above, seedling media preparation becomes a sensitive attribute as it is easier to perform than conventional seedling methods using polybags, and this ease leads to practices that consider environmental conservation. This research technology is compatible with the recommendations of the Food and Agriculture Organization (FAO) [35], where the concept of sustainable development must manage and conserve natural resources (the use of Rawapening Lake sediments) and orient more efficient technological changes (from conventional technology to the use of soil block technology) to meet sustainable human needs for current and future generations. The depletion of natural resources and environmental degradation must be reversed towards the discovery of new and renewable resource reserves accompanied by environmental quality improvement. Therefore, soil block technology can be one of the future technological solutions because it is environmentally friendly, utilizing biomass waste to produce high-value products.

3.2.4. Economic Dimension

In the leverage evaluation of the six attributes comprising the economic dimension, three attributes stand out as sensitive to sustainability price of seedling media, income increase opportunities, and input production access with RMS values of 1.88, 1.18, and 0.87, respectively (Figure 4). The price of the seedling media is the most sensitive factor affecting sustainability in the economic dimension. Product pricing is crucial because it affects consumer purchasing behavior; the cheaper a product, the more units will be sold [87]. The price of soil block seedling media in the research location is competitive because it has the same price as that of polybag media (IDR 25,000). At the same price level, the product quality of the soil block media was better. From the producer’s perspective, soil block media seedling production is faster and more efficient [6], meaning that in the same period of time, soil block media production produces more quantity with fewer resources (cost, labor, time, and raw materials).

The second sensitive attribute that affects economic sustainability is the potential opportunity for increased income. The production speed and resource efficiency of soil block seedling media were directly proportional to the potential for increased income, as evidenced by the fact that the income of soil block seedling media producers increased by 90.24% compared to polybag media (Table 6). In addition, soil block seedling media can increase production capacity because they can be produced in large quantities in a shorter time. As Mutunga and Owino [22] stated, increasing production capacity has a positive impact on increasing income.

The third crucial factor affecting economic sustainability is the accessibility of production inputs or raw materials. The ease with which business actors can access raw materials (such as organic fertilizer, Rawapening Lake sediment, cocopeat, dolomite, natural phosphate, and labor) has a positive effect on increasing production [88,89] and supports the sustainability of a business. As Hulopi et al. [89] showed, supporting activities in the upstream agribusiness subsystem has a significant effect on increasing production. In addition, all raw materials as production inputs are domestic and environmentally friendly, utilizing waste such as Rawapening sedimentary peat, cocopeat, and organic fertilizer. Economically, the utilization of domestic raw materials can improve business performance and maintain sustainable growth [90].

3.2.5. Social Dimension

Of the eight variables examined, the two most sensitive to sustainability were enhanced female participation (RMS = 3.72) and the chance to strengthen community resilience (RMS = 2.86) (Figure 5). Women’s participation is vital because they are careful, thorough, and capable of multitasking in nursery settings. Furthermore, flexible working hours enable women to fulfill their domestic responsibilities while contributing financially [91]. This aligns with the principle of gender equality and has been shown to boost productivity [92].

Opportunities for community resilience can be realized by empowering women, developing social networks, and enhancing social inclusion. Individual and family well-being improves when women have greater access to resources and participate in decision-making [93]. On the other hand, robust social networks and collaboration among farmers, seed producers, academics, and other stakeholders will foster solidarity and creativity in the development of nursery businesses [94]. This strategy allows vulnerable groups such as smallholder farmers and the impoverished to participate actively, thus contributing to the reduction in social inequities at the local level.

Other attributes, such as labor absorption and increased community awareness, show low leverage values, which need to be improved through participatory education and outreach so that the social impact of this innovation can be more widespread. It is also important to complement the role of women’s empowerment and strengthen social networks so that all elements of society, including vulnerable groups, can be actively involved in the nursery business and share benefits more evenly.

3.2.6. Institutional Dimension

The leverage analysis within the institutional dimension identified three key attributes critical for the sustainability of soil block nursery businesses: government support (RMS 3.82), private sector support (RMS 3.56), and the presence of marketing institution support (RMS 2.51) (Figure 6). Government support is expected to focus on providing production facilities, marketing assistance, and capacity building through training programs. However, current support remains inconsistent and limited, as highlighted by Komalawati et al. [34], who emphasized the government’s crucial role in ensuring business sustainability through regulations, funding, and promotion. Similarly, private sector support, such as corporate collaborations and Corporate Social Responsibility (CSR) initiatives, has been underutilized, while nursery associations continue to prioritize traditional plastic or polybag packaging. Marketing poses a major challenge due to farmers’ limited awareness of the quality advantages of soil block media seedlings.

To ensure effective and sustainable support, a dedicated institution is needed to coordinate the development of soil block seedling media businesses. This institution can manage capital, provide production inputs, and facilitate marketing knowledge and training for business operators [95,96]. Currently, the lack of a specialized institution has led to fragmented government and private sector support, which hinders businesses’ sustainability. Therefore, this study underscores the necessity of establishing a dedicated institution supported by stakeholder commitment, the government, and the private sector to address coordination gaps and enhance the growth of soil block nursery businesses.

4. Conclusions and Recommendations

This study assessed the feasibility and sustainability of soil block seedling media utilizing Rawapening Lake sediment through integrated LCA and MDS. The soil block system demonstrated a 48% reduction in GWP, improved nutrient content, and higher economic efficiency compared to conventional polybag media.

The RAPsoilblock method, a practical analytical tool for assessing the sustainability of soil blocks as agricultural seedling media, indicates that the environmental dimension holds the highest sustainability index, classified as moderately sustainable. This is followed by the technological, economic, and social dimensions, which also fall within the same sustainability category, reflecting a relatively balanced performance across these aspects. In contrast, the institutional dimension recorded the lowest index, placing it in the less sustainable category. The institutional dimension was identified as the weakest link, indicating limited policy and structural support for broader adoption. These findings highlight the need for institutional strengthening, market development, and social empowerment, particularly enhancing community involvement and women’s participation, to ensure long-term sustainability.

Future research should consider scalability by analyzing long-term sediment supply logistics, capital support mechanisms for farmers, and the potential of cooperative models to facilitate shared use of soil block machines. This study is limited by its geographic scope and sample size and lacks a long-term impact assessment. Future research should broaden the analysis, include temporal dynamics, and engage policy stakeholders to facilitate scaling-up and commercialization of this environmentally friendly innovation.