Soil Quality and Innovation in Agriculture

1. Soil Quality: A Fundamental Concept for Sustainability

Life on Earth depends on healthy soils. As the living skin of our planet, soil lies at the heart of Earth’s terrestrial ecosystems, playing a crucial role in agricultural productivity, carbon sequestration, water filtration, and biodiversity. However, soils are fragile, and the impact of our actions is often overlooked. Increasing pressures from intensification, climate variability, pollution, and land-use change, challenge the sustainability of this vital resource. To ensure a healthy and green future for current and future generations, we must protect and take care of our soils.

The soil quality concept provides a comprehensive framework for understanding the interactions between soil’s biological, chemical, and physical properties [1]. This holistic approach is essential for sustainable use and effective management of non-renewable soil resources [1,2]. Pioneering work by Larson and Pierce (1991) introduced this concept and proposed a “minimum data set” of indicators for its assessment [3]. Building on this, Doran and Parkin (1994) offered a widely accepted definition, characterizing soil quality as “the capacity of a specific kind of soil to function, within natural or managed ecosystem boundaries, to sustain plant and animal productivity, maintain or enhance water and air quality, and promote plant, animal, and human health.” [4]. While the concept has faced ongoing debate and criticism [5], a rising number of studies emphasize its fundamental importance for environmental sustainability and human well-being [6,7].

This Special Issue, “Soil Quality and Innovation in Agriculture: Dynamics, Indicators, and Sustainability,” addresses the vital concept of soil quality, examining the relationships between biological, chemical, and physical soil parameters in the context of sustainable land use and management. Soil quality degradation poses a significant challenge to the agricultural sector, and effective soil management is essential for improving soil health [8]. Assessing soil quality involves considering physical, chemical, and biological properties as indicators, which can help identify factors that inhibit soil function and monitor the effects of various management practices [9].

This Special Issue brings together 13 original studies from diverse regions and soil environments to explore the state, monitoring, and enhancement of soil quality, integrating emerging innovations and sustainability perspectives.

2. Key Themes from the Research

The collected works span experimental, methodological, and applied frameworks that deepen our understanding of soil quality indicators, carbon and nutrient dynamics, biological function, and sustainable land use. From Croatia, China, and Poland to the Mediterranean and Peru, the research captures regional variations while aligning with global efforts to restore and sustain soil health. Several key themes emerge from the research presented in this Special Issue:

• Soil quality as affected by Soil Carbon and Nutrient Dynamics in Agricultural Systems: Several papers emphasize the influence of land management on carbon fluxes and nutrient cycling. Bhandari et al. (2025) evaluated the biological soil quality indicator of soil respiration in maize, wheat, and barley, demonstrating crop-specific dynamics that highlight the influence of crop type, temperature, and moisture on carbon cycling. Xin et al. (2025) conducted a detailed spatial assessment of soil organic carbon, Nitrogen, and Phosphorus stocks across cropping systems in arid Northwest China, identifying paddy and orchard systems as the most effective for nutrient retention. Similarly, Kondratowicz-Maciejewska et al. (2025) highlighted how organic amendments affected enzymatic activity and labile carbon pools in sandy soils, while Lemanowicz et al. (2025) illustrated how tillage regimes shape both physical soil structure and microbial function.
• Effect of Organic Amendments and Soil Restoration Management on Soil Quality: In East-Central Poland, Malinowska and Kania (2025) demonstrated the dual benefits and risks of applying waste-derived organic matter—enhancing nitrogen and microbial activity but increasing heavy metal content under some treatments. In the U.S., Young and Sherman (2024) compared solid dairy manure sources and their greenhouse gas profiles relative to corn yield, showing the need to align organic input strategies with soil aeration status to optimize climate outcomes. In Turkey, Bilen et al. (2025) brought an industrial lens to soil quality, examining how cement dust emissions interact with tillage systems and microbial indicators.
• Indicators of Soil Health and Long-Term Practices: Long-term data underscore the cumulative effects of soil management. Hewelke et al. (2024) documented how no-till systems over decades increased soil organic carbon, aggregate stability, and water retention in Polish soils. Samaniego et al. (2025) aimed to develop and spatially evaluate a Soil Quality Index (SQI) tailored to a mountainous region in Peru, using a combination of Principal Component Analysis (PCA) and Expert Opinion (EO) with linear and non-linear scoring functions to assess soil health. Evangelou and Giourga (2024) applied multivariate methods to Mediterranean agroecosystems, pinpointing total nitrogen and C/N ratio as reliable indicators of land use impacts among 23 soil physical, chemical, and biological soil quality indicators. Such work provides tools for simplified yet meaningful monitoring, especially in data-scarce regions.
• Innovations for Soil Enhancement and Pollution Mitigation: Several papers explored innovative interventions and remediation techniques. Liu et al. (2024) analyzed how compounding sandy soil with Pisha sandstone altered electrochemical properties and structural stability, a promising technique for erosion-prone areas. Espada et al. (2024) performed a life cycle assessment comparing phytoremediation strategies for copper-contaminated soils, finding that alfalfa with biomass cogeneration yielded the best environmental performance. This systemic view adds a much-needed climate and energy lens to soil restoration practices.
• Urbanization and Land Transformation. Impacts on Soil Quality: Finally, Wang et al. (2024) examined rural urbanization’s impact on soil organic matter in Northeast China, using spatial analysis to show both gains and losses associated with urban encroachment and mechanization. These findings highlight the importance of contextualizing soil quality within socio-economic transitions, especially in rapidly changing peri-urban landscapes.

3. Conclusions

Collectively, the contributions to this Special Issue illustrate the multidimensional nature of soil quality and the array of emerging innovations, from UAV-based precision agriculture to organic recycling, long-term conservation practices, and life cycle tools. The papers reaffirm that soil is not merely a substrate, but a living, dynamic system shaped by biological, chemical, physical, and human forces.

The research presented here identifies appropriate indicators and implements innovative management practices to maintain and improve soil health. From carbon cycling to tillage systems, waste management to pollution impacts, the papers in this issue provide a comprehensive overview of the challenges and opportunities in soil science today.

As pressures on soils intensify globally, the works presented here offer critical knowledge for guiding evidence-based policy, adaptive management, and technological advancement. The diversity of methods and settings showcased in this collection reflects the complexity of soil systems—and our collective responsibility to sustain them. We thank the contributors and reviewers for their valuable work in making this Special Issue a success.

We hope this Special Issue offers valuable reference for researchers, practitioners, and decision-makers working toward resilient, productive, and climate-smart soil systems that enhance soil quality and environmental health.