Bridging the Gap: Evaluating Farmers’ Sustainability Perceptions, Their Agricultural Practices, and Measured Soil Indicators Towards Promoting a Sustainable Viticulture

Abstract

This study investigates the relationships between farmers’ perceptions, their agriculture practices, and objective soil health indicators in a viticultural subzone of the Madrid region, aligning with the EU’s Farm to Fork Strategy. A dual-methodology approach was employed, combining detailed soil chemical and physical analyses with a structured survey of thirty-four local farmers. Soil samples were analyzed for pH, nutrient concentrations (nitrogen, phosphorus, and potassium), and heavy metals (nickel, lead, and cadmium), while the survey captured farmers’ perceptions regarding soil contamination and sustainable practices. Results showed significantly higher levels of nitrogen (0.09% vs. 0.04%), phosphorus (125 vs. 65 mg/kg), and potassium (3100 vs. 1550 mg/kg) in fertilized plots (p < 0.05), while heavy metals remained within safe limits, compared to those not using fertilizers, as confirmed by Mann–Whitney U tests (p < 0.05). However, the impact on heavy metal accumulation was minimal, with only a slight decrease in nickel levels in fertilized plots. Additionally, the survey revealed low adoption rates of conservation agriculture techniques and limited training on sustainable practices, despite strong environmental commitment among farmers. These findings underscore the need for regular soil testing, targeted educational initiatives, and the increased promotion of conservation practices to better align subjective assessments with scientific evidence, ultimately enhancing both productivity and ecological resilience in sustainable viticulture.

1. Introduction

The European Union’s Farm to Fork Strategy (F2FS) stands as a pioneering and ambitious initiative, addressing with determination the complex challenges associated with sustainability, food security, and public health in the food chain [1,2,3]. The EU supports the F2FS through specific regulations [4,5,6,7,8]. The F2FS aims to establish a closer connection between agricultural production and the final consumption of food, proposing a radical transformation in how food is produced, distributed, and consumed in the European Union (EU) [9]. Its primary focus on environmental sustainability and consumer health propels its mission throughout the entire food chain [10].

In this study, the term “fertilizer” refers specifically to mineral (synthetic) fertilizers unless otherwise stated. Organic inputs such as manure are discussed separately when applicable. The strategy emphasizes a substantial reduction in the use of pesticides and fertilizers as a key component of a comprehensive sustainable agriculture approach. Reducing these inputs not only minimizes direct chemical loading but also mitigates secondary impacts such as nutrient leaching, soil acidification, and the disruption of soil microbial communities [11,12,13]. This reduction facilitates the adoption of integrated pest management and precision agriculture practices, which are essential for preserving soil structure and ensuring long-term fertility [14,15]. Moreover, by minimizing reliance on synthetic inputs, the strategy promotes resource-use efficiency and enhances the overall ecological resilience of agricultural systems. These reduced-input practices are designed to support the maintenance of soil biodiversity and the provision of ecosystem services, thereby contributing to a more sustainable production model that can adapt to environmental challenges.

The transition to organic farming stands out as a key objective, encouraging crop rotation and integrated pest management to safeguard soil biodiversity [16]. Additionally, the strategy directs its efforts toward strengthening the resilience of the agricultural sector in the face of climate and environmental challenges [17].

By directly connecting agricultural production with final consumption, the F2FS goes beyond ensuring food security; it aims to promote healthier and more sustainable eating habits. This holistic approach reflects the understanding that ecosystem health, soil biodiversity, and transparency in the food chain are essential elements for building a sustainable food future in the EU [18,19]. The reduction in pesticide and fertilizer use is not only aimed at preserving soil biodiversity but also at mitigating the negative environmental impacts associated with these substances. This focus on soil sustainability is essential to ensure the long-term productivity and resilience of agricultural ecosystems.

The promotion of organic farming practices aligns with the pursuit of more sustainable land use by emphasizing the importance of “soil health”. Soil health is defined following the European Commission’s Proposal for a Directive on Soil Monitoring and Resilience [20], which frames healthy soil as being “in good chemical, physical and biological condition and able to continuously provide essential ecosystem services”. These services include food production, water regulation, climate resilience, and biodiversity support. The term soil health is widely used in scientific literature to emphasize the soil’s dynamic and living nature [12,21,22,23,24,25,26], encompassing both its biotic and abiotic components. Unlike inert media, soils contain microbial life, organic matter, and structure that respond to management practices. Therefore, soil health serves as a functional concept to evaluate how well soils support ecological and agricultural functions over time.

By minimizing the use of intensive chemical inputs, organic farming fosters more balanced agricultural systems where soil health is prioritized. Moreover, empirical research demonstrates that transitioning to organic methods can significantly improve soil quality, enhance water retention, and reduce erosion.

This approach notably intertwines with the concept of the ecological footprint, a comprehensive metric born from ecological economics [27]. The ecological footprint quantifies human demand on nature, considering crucial elements such as land use, water consumption, and energy utilization [28].

Sustainable agriculture encompasses more than a reduction in input use. It integrates environmental integrity, economic viability, and social responsibility across time and space. Gerke (2025) emphasizes that sustainability in agriculture must be understood as a systemic balance, where biophysical and ecological processes are maintained to ensure long-term productivity and resilience [29]. Reduced input strategies, such as limiting synthetic fertilizers and pesticides, can support sustainability, particularly when combined with knowledge-based practices like crop rotation, organic amendments, and biodiversity-enhancing techniques. These strategies contribute to maintaining soil fertility, protecting water resources, and promoting agro-ecosystem services. Aligned with the ecological footprint framework, which quantifies human demand on the planet’s ecological capacity, the EU’s Farm to Fork Strategy represents a major policy effort toward sustainable and equitable agricultural systems. It seeks to minimize environmental impacts while securing food production and ecosystem health for future generations.

The F2F Strategy and the ecological footprint emerge as complementary tools in the pursuit of more sustainable agricultural practices and more conscious food systems [30]. Both initiatives acknowledge the need to adopt a holistic approach to ensure not only food security but also the ongoing health of ecosystems crucial for human survival and global well-being. The F2F Strategy, in alignment with the principles of the ecological footprint, stands as a significant step toward a more sustainable and equitable future for the coming generations.

In this context, the main objective of the research is to evaluate the relationship between farmers’ perceptions and their agriculture practices using the empirical soil indicators of their vineyards, providing insights into sustainable agricultural practices that align with the EU’s Farm to Fork Strategy. Our primary hypothesis posits that there is a significant discrepancy between farmers’ perceptions of soil fertility and the empirical data concerning soil nutrient levels and contamination indicators in viniculture practices. Additionally, a second hypothesis stands that farms using mineral fertilizers and pesticides will exhibit elevated soil nutrient levels, particularly nitrogen, phosphorus, and potassium, as well as an increased presence of heavy metals, such as lead, cadmium, and nickel, when compared to farms that adopt organic or reduced-input practices. A third hypothesis establishes that there is a significant discrepancy between farmers’ perceptions of their sustainable agricultural commitments and the actual management practices implemented on their vineyards.

2. Materials and Methods

2.1. Site Description

The research was conducted in the San Martín de Valdeiglesias viticultural subzone, in the westernmost part of the Madrid region. It is a significant contributor to the “Vinos de Madrid” Protected Designation of Origin (PDO) landscape. The subzone features nine municipalities, hosts eighteen wineries registered under the PDO, and dedicates 1575 hectares to vineyards. These wineries account for 22% of the vineyard area and contribute 25% to the annual wine production within the PDO. However, the wineries represent less than 15% of all producers in the “Vinos de Madrid” PDO, highlighting the subzone’s viticultural efficiency and productivity.

The subzone is located along the Alberche River, which provides a microclimate that optimizes conditions for grape cultivation. The region is defined by specific climatic and geographic parameters that enhance viticultural performance. Local viticultural practices prioritize environmental conservation by maintaining and promoting native grape varieties, specifically Garnacha Tinta and Albillo Real [31]. The climate of the studied region is temperate, with an average annual temperature of 7.8 °C (average annual minimum temperature of 3.8 °C and average annual maximum temperature of 12.8 °C) and a long-term average annual rainfall of 504 mm. Figure 1 illustrates the location of the wine production area featured in this study, with the area of the study indicated by hatching over the pink-highlighted PDO region.

2.2. Study Design

A dual-methodology approach was employed, comprising both chemical and physical analyses of soil samples and surveys on agri-environmental practices among farmers. The sampling method selection was the non-probabilistic method [32,33]. Researchers used earlier information to make the sample selection, instead of random selection.

2.2.1. Chemical and Physical Soil Analyses

A total of thirty-four vineyards’ plots were selected. In each plot, three soil samples were collected and mixed in August 2023 from vineyards in the municipalities of Cenicientos, Cadalso de los Vidrios, San Martín de Valdeiglesias, and Villa del Prado (Community of Madrid). Sample selection was strategically conducted across various plots belonging to cooperative members, ensuring a comprehensive representation of agricultural and environmental conditions. This approach facilitated a diverse and meaningful representation of the study area.

The collection of mixed soil samples followed standardized protocols as described by Carter & Gregorich (2007) [34,35] and Tan (2005) [34,35], ensuring reliable and consistent data. Multiple subsamples were collected across each vineyard plot at a standardized depth, then combined to create composite samples, minimizing localized variability. To prevent contamination, sampling tools were properly cleaned between collections, and samples were stored under controlled conditions to maintain their chemical and physical properties until laboratory analysis. These procedures ensured that the soil data accurately reflected the study area’s environmental conditions and management practices.

The samples underwent the specialized Edaphology laboratory analyses of the Universidad Politécnica de Madrid to ascertain their chemical and physical composition. The soil samples were analyzed using standard methods as described in Carter & Gregorich (2007) [34,35] and Tan (2005) [34,35], which include procedures for the physical and chemical analysis of agricultural soils. Evaluated parameters included pH levels, essential nutrient concentrations such as nitrogen, phosphorus, and potassium, the presence of heavy metals like lead, cadmium, and nickel, and soil organic matter content. These analyses provided a detailed assessment of soil fertility and potential contamination risks [36,37].

Table 1. Soil property and method for analysis.

Soil Property	Method	Reference
pH and Electrical Conductivity	Extract 1:2.5	[38,39]
Total Organic Matter	560 °C Calcination	[40,41]
Easily Oxidizable Organic Matter	Walkley y Black
Organic Carbon
Nitrogen (N)	Kjeldahl Method	[42]
Phosphorus (P)	Olsen Method	[43]
Potasium (K)	Acid Digestion with HCl/HNO3	[44]
Total Metals
Texture	Densímeter of Bouyoucos	[45]
Field Capacity (moisture retention at 33 kPa), Wilting Point (moisture retention at 1500 kPa, Available Water)	Richards Membrane (1954), measuring water retained in the sample at 33 and 1500 kPa	[46]

shows the soil properties analyzed, and the technical method used for the analysis. Data on the soils of the vineyard’s plots are included in Appendix A.

Maps were generated to understand the spatial distribution of soil physical characteristics based on the samples collected, using ArcGIS Desktop (ArcMap) 10.8.2 (Geographic Information Systems) [47,48] as a primary analytical tool. GIS enabled the creation of detailed maps showing the distribution of soil pH, texture (sand and clay content), and available water across the study area. The maps are included in Appendix B.

2.2.2. Agri-Environmental Practices Questionnaire

In parallel, a survey was conducted among the farmers to gather insights into their agri-environmental practices and perceptions regarding soil contamination due to fertilizer use and other soil management practices. This component of the study aimed to understand farmers’ awareness and attitudes towards environmental sustainability linked to soil management in their agricultural practices. The design of the survey was conducted through a structured questionnaire comprising twenty-eight questions (Qs) divided into seven sections. The Qs were formulated to assess various dimensions of sustainable agricultural practices, specifically tailored to the agricultural context of the five municipalities of the Madrid PDO subzone area.

The questionnaire focused on topics such as fertilizer and pesticide use, efficiency in the use of irrigation techniques [49,50,51], sustainable soil management practices [52,53], agriculture waste management [54,55], farmers’ training, certification in sustainable agricultural practices [56,57,58], and environmental awareness commitment [59,60,61]. Fourteen Qs were dichotomic (Yes/No); thirteen Qs were closed-ended, providing respondents with limited answer choices to facilitate efficient data analysis; and one open-ended Q was included to allow respondents to provide more detailed explanations regarding training. In addition, a Likert scale [62] was utilized, incorporating both a qualitative scale and a quantitative variable (V_Qx) to measure and assess the answers.

Figure 2 provides an overview of the questionnaire structure, including questions and variables. The questionnaire is included in Appendix C.

The questionnaire was made with Google forms software 2024 [63]. Each farmer received the questionnaire by email once from October 2023 to November 2023.

The survey was completed by thirty-one farmers, and the data were analyzed using SPSS (IBM SPSS Statistics v27.0) and Excel (MS Excel v18.0) to calculate frequencies and central tendency values, as well as to perform non-parametric tests using the Mann–Whitney U test. The Mann–Whitney U test was chosen because it is well-suited for comparing two independent groups—in this case, farms using mineral fertilizers (coded as 1 for “Yes”) versus those not using them (coded as 0 for “No”)—especially when the data may not follow a normal distribution. Soil parameter variables (N, P, K, Ni, Pb, and Cd) were extracted for each observation and ranked. The Mann–Whitney U test (significance level of p < 0.05) then compared the distributions of these ranked values between the two groups, providing p-values to test the null hypothesis that there is no difference in soil parameter concentrations between farms that use mineral fertilizers and those that do not.

3. Results

3.1. Soil Composition Analysis

The soil samples were analyzed for key chemical and physical parameters, including pH levels, nutrient concentrations (N, P, K), heavy metal presence (Pb, Cd, Ni), and organic matter content. Appendix A displays the chemical and physical parameter data on the soils of the vineyards plots.

3.2. Survey Responses and Soil Data

This approach allowed us to assess whether fertilizer use is associated with statistically significant differences in soil nutrient levels and heavy metal concentrations at a significance level of p < 0.05.

Table 2. Comparison of Soil Parameter Means between farms using mineral fertilizers (YES) and those not using them (NO) (Mann–Whitney U Test, p < 0.05).

Soil Parameter	Units	Mean (YES)	Mean (NO)	p-Value
Nitrogen (N)	%	0.090	0.040	0.035
Phosphorus (P)	mg/kg	125	65	0.020
Potassium (K)	mg/kg	3100	1550	0.015
Nickel (Ni)	mg/kg	0.13	0.18	0.045
Lead (Pb)	mg/kg	0.04	0.04	0.950
Cadmium (Cd)	mg/kg	0.09	0.09	0.880

summarizes the soil parameter means for farms reporting fertilizer use (Yes, coded as 1) versus those not using fertilizers (No, coded as 0), along with the p-values from the Mann–Whitney U tests (significance set at p < 0.05).

The Mann–Whitney U test results indicate that farms using mineral fertilizers (Yes) have significantly higher levels of key nutrients compared to those not using them. Among respondents not using mineral fertilizers, 26% reported the use of organic amendments such as manure, compost, or green cover crops to maintain soil fertility. Specifically, N, P, K are significantly elevated in the Yes group, with p-values of 0.035, 0.020, and 0.015, respectively. These findings suggest that fertilizer application is associated with increased soil nutrient concentrations. In contrast, for heavy metals, the concentration of nickel is slightly lower in the Yes group (p = 0.045), indicating a weak negative association. However, Pb and Cd levels do not differ significantly between the two groups (p = 0.950 and p = 0.880, respectively). Overall, these results reinforce that while mineral fertilizers effectively enhance soil nutrient levels, their impact on heavy metal accumulation is minimal.

In the survey, 55.6% of farmers reported using chemical fertilizers, with the most common types being ammonium nitrate, diammonium phosphate, urea, and potassium sulphate. However, a significant 66.7% of respondents did not conduct soil testing to determine the nutritional needs of their crops.

3.2.1. Survey Pesticide Application Frequency Responses and Heavy Metal Levels

Pesticide application was infrequent, as 70.4% of farmers applied pesticides rarely and 29.6% reported never using them. The concentration of heavy metals (e.g., Pb, Cd) in the soil is shown in

Table 3. Relation between pesticide application frequency and heavy metal levels.

Pesticide Application Frequency	% Farmers	Average Pb (mg/kg)	Average Cd (mg/kg)
Never	29.6	0	0
Rarely	70.4	0	0

.

3.2.2. Survey Irrigation Practices Responses and Soil Moisture Retention

In terms of irrigation, only 11.5% of respondents employed irrigation methods; however, among those who did, 83.3% reported using efficient systems such as drip irrigation. Efficient irrigation practices, such as drip irrigation, were associated with improved soil moisture retention, critical for vine health and resilience.

Table 4. Relation between efficient irrigation practices and average soil moisture levels.

Use of Efficient Irrigation Systems	% Farmers	Average Soil Moisture (%)
Yes	11.5	10.79
No	88.5	7.80

highlights that those soils with efficient irrigation systems retained significantly higher moisture levels.

3.2.3. Survey Sustainable Practices Responses and Soil Health

Farmers employing conservation agriculture techniques, such as cover cropping and the use of mulch, demonstrated superior soil health indicators, notably, higher average soil organic matter. Specifically, respondents who implemented these practices (29.6% of the sample) exhibited an average soil organic matter content of 4.79%, compared to 2.77% for those who did not. The enhanced organic matter is critical for nutrient cycling, water retention, and overall soil resilience.

Furthermore, the questionnaire collected data on various agricultural practices, perceptions of soil contamination, and sustainable farming methods.

Table 5. Agricultural practices responses.

Agricultural Practice	Results
Use of Chemical Fertilizers	55.6% of respondents reported using chemical fertilizers.
	Common types of fertilizers used include ammonium nitrate, diammonium phosphate, urea, and potassium sulphate.
Soil Testing	66.7% of respondents do not conduct soil testing to determine the nutritional needs of their crops.
Pesticide Application:	Frequency of pesticide application varied, with 70.4% applying rarely; and 29.6% that never applied.
Irrigation Practices:	11.5% of respondents use irrigation.
	83.3% reported using efficient irrigation systems like drip irrigation.
Sustainable Practices	70.4% maintain areas of natural vegetation to promote biodiversity.
	29.6% practice conservation agriculture techniques such as soil cover.
	37% considered tillage contributes positively to vineyard sustainability and 48.1% reported that it depends on the specific tillage practice used.
	41.7% reported that they used more than 500 L for land tilling per year, in contrast to 33.3% that used between 0 and 100 L per year
Waste management	66.7% burned pruning waste in the field
	50% explored using waste for firewood (fuel) and 33.3% used it as fertilizer
	74.1% did not have an agricultural waste management plan
	69.6% recycled or reused agricultural materials, such as pesticide containers and irrigation equipment
Training	81.5% have not received training on sustainable agricultural practices in the last two years
Certification and Recognition	66.7% participate in cooperatives or associations that promote agricultural sustainability
	92.6% reported that they have not obtained any certification or recognition related to sustainable and/or organic agricultural practices
Environmental Commitment	76.9% informed us that they would like to receive additional information on reducing the environmental impact of their agricultural practices
	88.9% considered it important to reduce the ecological footprint of agriculture in the Sierra Oeste of Madrid

summarizes the main responses regarding these practices among the farmers.

4. Discussion

Integrating empirical data with subjective perceptions offers a holistic view of the challenges and opportunities in sustainable soil management in agriculture, particularly concerning the Farm to Fork Strategy, which advocates for practices ensuring the long-term sustainability of agricultural ecosystems and food security. This methodological approach not only highlights areas of discrepancy between perception and reality but also provides a foundation for the development of more informed and effective interventions and policies in sustainable agriculture [3].

The results show that pH levels are generally within a suitable range for viticulture, neither overly acidic nor alkaline, which supports vine health by maintaining essential nutrient availability and microbial diversity. This aligns with findings that soil pH plays a pivotal role in grapevine root health, nutrient uptake, and soil microorganism balance, all of which are crucial for high-quality grape production [64,65].

N levels varied significantly across samples, indicating a diversity in soil fertility, aligned with the findings of Hawk, J (2007) [66]. P was found to be adequate but variable, with lower concentrations in certain areas. High K levels across samples are beneficial for vine vigor and fruit development, as potassium supports photosynthesis and water regulation, both essential for grape quality.

Similar studies have shown that while mineral fertilizers boost N, P, and K levels, they can disrupt natural nutrient cycles and lead to acidification, which can be mitigated through balanced soil management [67,68,69,70]. Heavy metals were found in trace amounts, with Pb detected within safe limits, though some samples indicated slightly higher levels, potentially affecting long-term soil health. Cd and Ni were present in low concentrations, suggesting minimal risk of toxicity. Prior research emphasizes that heavy metals accumulate in vineyards due to pesticide application, especially in acidic soils, where they become more mobile and bioavailable, potentially impacting vine growth if not managed sustainably [71,72,73,74,75].

Our findings show that farmers who used mineral fertilizers had higher average N, P, and K levels in the samples of their plots. This aligns with studies showing that mineral fertilizers increase these nutrient levels, though they can also degrade soil structure and organic matter over time, especially when used without soil testing and nutrient balancing strategies.

Diversity in N levels in soil fertility could impact vine growth and grape quality, aligned with the findings of Hawk, J. (2007) [66]. As Schreiner, RP (2000) reported in their findings, the lower concentrations of P in certain samples could limit plant growth [76]. High K levels across samples are beneficial for vine vigor and fruit development, as potassium supports photosynthesis and water regulation, both essential for grape quality. Similar studies have shown that while mineral fertilizers boost N, P, and K levels, they can disrupt natural nutrient cycles and lead to acidification, which can be mitigated through balanced soil management [67,68,69,70]. Sustainable soil practices, such as organic fertilization and soil testing, are recommended to prevent nutrient imbalance and excessive soil acidification.

The analysis of agricultural practices and soil quality indicators reveals meaningful relations, shedding light on the influence of specific management techniques on soil health. Farmers who applied mineral fertilizers showed higher nutrient levels in their soil, yet faced potential risks of over-fertilization and nutrient leaching, which can disrupt soil structure and long-term fertility [77,78].

The frequency of pesticide applications did not show elevated levels of heavy metals, such as Pb and Cd; however, our sample of farmers provided barely any or no information on pesticide applications, so our results are not conclusive. It is relevant to highlight that heavy metal residues, particularly Pb and Cd, are routinely analyzed in wine products as part of quality control and food safety standards [79,80,81]. Even trace contamination in soils can affect grape composition and must be monitored continuously. As alternatives to synthetic pesticides, strategies such as Integrated Pest Management, the introduction of natural predators, and the use of biofungicides offer promising approaches to maintaining vineyard health while reducing chemical inputs [82].

Our findings show that only a small group of farmers irrigate their vineyards (11.5%), and most of them (88.3%) use efficient irrigation, as it enhances water use efficiency. Practices such as efficient irrigation and sustainable farming practices, including organic fertilization, contribute positively to soil health; these are in line with the environmental objectives of the EU’s Farm to Fork Strategy [83].

This aligns with established research that conservation practices promote soil health by increasing organic matter, enhancing water retention, and reducing soil erosion. While conservation agriculture practices such as cover cropping and reduced tillage have been widely associated with increased soil organic matter (SOM) and improved soil structure in the upper soil layers [84,85], recent research highlights the need for a more nuanced interpretation. For instance, Alcántara et al. (2016) demonstrated that single deep plowing can significantly increase SOC stocks at the plot scale when measured on a hectare basis, due to the deeper incorporation and stabilization of organic matter [86]. This contrasts with conservation systems, which typically concentrate SOC accumulation in the top 5–10 cm of soil. Consequently, while reduced tillage may be effective for enhancing surface-layer soil health and microbial activity, its impact on total SOC across the entire soil profile may be less pronounced compared to well-managed deep tillage strategies. These practices also support biodiversity by fostering a balanced ecosystem that reduces dependency on chemical inputs, aligning with sustainable vineyard management objectives. This strategic alignment suggests that sustainable practices not only enhance productivity but also advance ecological sustainability in viticulture. The promotion of organic viticulture may further enhance grape quality by increasing the concentration of beneficial secondary metabolites. Studies have shown that organic practices are associated with higher levels of phenolic compounds, such as resveratrol, which contribute to both plant resilience and wine antioxidant properties [87].

The cross-analysis between survey responses and soil data highlights critical gaps between farmer perceptions and actual soil conditions. Many farmers lacked precise data on nutrient and heavy metal levels, leading to either an underestimation or overestimation of their soil’s fertility needs. Those who conducted regular soil testing had a more accurate understanding of their soil’s nutrient status, illustrating the importance of empirical data in effective soil management. Regular testing enables more tailored fertilization strategies, potentially reducing over-fertilization and its associated risks. Pesticide usage is minimal, with some farmers implementing anti-drift measures and adjusting application based on weather conditions, though others lacked such measures. Irrigation practices, notably the use of drip irrigation, were common, indicating an awareness of water conservation. A substantial proportion (70.4%) maintain areas of natural vegetation to promote biodiversity, a practice that is known to enhance ecosystem services and contribute to overall soil health [88,89]. However, only 29.6% of farmers reported using conservation agriculture techniques such as soil cover, suggesting that while biodiversity is a priority, the adoption of other sustainable soil management practices remains limited. Moreover, regarding tillage practices, 37% of respondents believe that tillage contributes positively to vineyard sustainability, whereas 48.1% assert that its impact depends on the specific practice employed. Notably, 41.7% of farmers reported using more than 500 L of fuel for land tillage per year, compared to 33.3% who used between 0 and 100 L. This variability highlights significant differences in management intensity that may influence soil structure and erosion [90,91]. In waste management, 66.7% of farmers burn pruning waste in the field, a practice that can release pollutants and diminish nutrient recycling efficiency [92]. Although 50% of the respondents have explored using waste as firewood and 33.3% as fertilizer, a concerning 74.1% lack a formal agricultural waste management plan. On a positive note, 69.6% recycle or reuse agricultural materials such as pesticide containers and irrigation equipment, indicating some engagement with circular economy principles [54,55].

The survey also indicates a significant training gap, with 81.5% of farmers not having received any training on sustainable agricultural practices in the last two years. While 66.7% participate in cooperatives or associations promoting sustainability, an overwhelming 92.6% have not obtained any certification in sustainable or organic practices.

Environmental commitment among the farmers is strong, as 76.9% expressed a desire to receive additional information on reducing the environmental impact of their practices, and 88.9% consider reducing the ecological footprint of agriculture in the Sierra Oeste of Madrid to be important. This high level of environmental awareness is promising and underscores the potential benefits of targeted educational programs and policy interventions to further promote sustainable viticulture [93,94,95,96].

Strength and Limitation of the Study

The strengths of this study lie in its comprehensive approach to evaluating the relationships between farmers’ perceptions about their agricultural practices and soil health indicators in viticulture. By integrating empirical soil data with survey responses from farmers, the study offers a holistic view of both measurable soil quality metrics and the perceptions and behaviors that drive farming practices. This dual approach enables a deeper understanding of how practices like fertilization, pesticide application, and irrigation affect key soil parameters such as nutrient levels, heavy metal content, and moisture retention.

Another strength is the study’s alignment with sustainability frameworks, such as the EU’s Farm to Fork Strategy, which reinforces its relevance to contemporary environmental and agricultural goals. The study’s recommendations are based on both observed data and current sustainable practices, supporting actionable improvements in viticulture that could be widely applicable.

However, the study has several limitations. First, the reliance on self-reported survey data introduces potential biases, as farmers’ perceptions and reported practices may not fully align with actual practices. Additionally, while the soil sampling provided valuable insights, the sample size and geographic coverage were limited to a specific region, which may limit the generalizability of the findings to other viticultural areas with different soil compositions and climate conditions. Another limitation is that the study focuses on a relatively short time frame, capturing only the immediate effects of agricultural practices rather than long-term impacts. Longer-term studies would be beneficial to fully understand the cumulative effects of practices like pesticide use and organic matter management on soil health and vineyard productivity.

Overall, while the study provides valuable insights and practical recommendations, future research could enhance these findings by expanding the sampling area, incorporating longitudinal data, and integrating more precise measurements of certain variables, such as soil microbiome composition and ecosystem biodiversity.

5. Conclusions

This study assessed the alignment between farmers’ perceptions, their agricultural practices, and measured soil health indicators in a viticultural region of Madrid. While nutrient levels (N, P, K) were significantly higher in plots with fertilizer use, many farmers lacked soil testing, highlighting the risk of over-fertilization and the need for better-informed nutrient management strategies.

Heavy metals (Pb, Cd) appeared in trace amounts, with no significant differences linked to pesticide use. However, the absence of formal waste management plans among most farmers may pose future environmental risks. Sustainable practices such as soil cover and natural vegetation management were moderately adopted, though training gaps and low certification levels limit broader implementation.

Efficient irrigation practices were associated with improved soil moisture, and biological pest control should be further explored as an alternative to synthetic pesticides. Promoting organic viticulture could offer additional benefits, including improved grape quality and reduced environmental impacts. In this context, strengthening farmer education and training on sustainable soil management, organic farming techniques, and integrated pest control is critical to fostering behavior change and improving environmental outcomes.

Overall, the study underscores the need for regular soil monitoring, farmer training, and incentives for sustainable practices to align viticulture with the EU’s Farm to Fork Strategy. These actions are essential to foster ecological resilience and sustainable productivity in Mediterranean vineyard systems.

Future research should aim to expand the dataset to include more detailed agronomic information; such as fertilizer doses, irrigation volumes, and seasonal timing of input, to better model their relationships with soil parameters. Longitudinal studies are also needed to evaluate how sustained changes in practices influence soil organic carbon, nutrient dynamics, and vine performance.