Measuring Soil-Water and Shrinkage Curves of Kaolin – BIOENGINEER.ORG

Report on the Sustainable Development Implications of Research into Kaolin Clay Dynamics

1.0 Introduction and Research Synopsis

A study conducted by Liu, Rahardjo, and Li, published in Scientific Reports, provides a detailed analysis of the soil-water characteristic curve (SWCC) and shrinkage behavior of consolidated kaolin clay. The research investigated these properties under both continuous and discrete drying procedures, yielding critical insights into soil mechanics. This report evaluates the study’s findings, with a significant emphasis on their alignment with and contribution to the United Nations Sustainable Development Goals (SDGs).

2.0 Key Research Findings

The investigation employed advanced instrumentation to simultaneously measure the SWCC and shrinkage curves of kaolin, a widely used clay mineral. The primary findings highlight the differential impact of drying methods on soil behavior.

• Continuous Drying: Resulted in predictable and uniform shrinkage behavior, simulating gradual environmental moisture reduction.
• Discrete Drying: Caused abrupt changes in soil volume, mirroring real-world scenarios of intermittent rainfall and rapid evaporation, which are becoming more common due to climate change.

This distinction is fundamental for accurately predicting soil stability and volumetric changes, which has profound implications for sustainable land management and infrastructure development.

3.0 Contribution to Sustainable Development Goals (SDGs)

The research findings provide foundational knowledge that directly supports the achievement of several key SDGs.

3.1 SDG 2: Zero Hunger

The study enhances the understanding of soil-water interactions, which is crucial for sustainable agriculture and food security.

• Improved Water Management: Insights into soil water retention can optimize irrigation practices, conserving water and ensuring crop viability in arid regions.
• Enhanced Soil Health: Understanding soil shrinkage helps in developing strategies to prevent soil degradation and desertification, thereby maintaining fertile land for agricultural productivity.

3.2 SDG 9: Industry, Innovation, and Infrastructure

The research provides critical data for building resilient and sustainable infrastructure.

• Geotechnical Engineering: Engineers can use this data to design more durable foundations and structures on kaolin-rich soils, which are susceptible to volume changes.
• Risk Mitigation: Accurate prediction of soil behavior under various moisture conditions helps mitigate risks of structural failure, contributing to safer and more sustainable infrastructure.

3.3 SDG 13: Climate Action

The study’s focus on different drying scenarios directly addresses challenges posed by climate change.

• Climate Adaptation: Understanding how soils respond to extreme and fluctuating moisture levels is vital for developing adaptation strategies in regions prone to droughts and intense rainfall.
• Carbon Sequestration: Healthy, stable soils play a role in carbon sequestration. This research contributes to soil management practices that support this natural climate solution.

3.4 SDG 15: Life on Land

The research is integral to the protection and restoration of terrestrial ecosystems.

• Combating Land Degradation: Knowledge of soil shrinkage and water retention is essential for implementing measures to halt and reverse land degradation.
• Ecosystem Health: Stable soil structure is the foundation of healthy ecosystems. This study provides insights that support the maintenance of soil integrity and overall ecosystem welfare.

4.0 Conclusion and Future Directives

The research by Liu, Rahardjo, and Li offers significant contributions to soil science with direct applications in achieving global sustainability targets. The findings underscore the necessity of considering environmental drying conditions in geotechnical and agricultural models.

1. Policy and Practice Integration: The results should inform policy related to land use, construction codes, and agricultural water management to better align with sustainability principles.
2. Expanded Research: Future studies should extend this methodology to other soil types and a wider range of environmental conditions to build a comprehensive global soil behavior database.
3. Interdisciplinary Collaboration: The findings highlight the need for collaboration between soil scientists, engineers, climate scientists, and policymakers to translate this knowledge into effective, sustainable solutions that advance the SDGs.

5.0 Reference Details

• Article Title: Simultaneous determination of soil-water characteristic and shrinkage curves of consolidated kaolin under continuous and discrete drying procedures.
• Authors: Liu, H., Rahardjo, H. & Li, Y.
• Publication: Scientific Reports 15, 40042 (2025).
• DOI: https://doi.org/10.1038/s41598-025-23981-1

Analysis of Sustainable Development Goals in the Article

1. Which SDGs are addressed or connected to the issues highlighted in the article?

• SDG 2: Zero Hunger: The article connects the research to agriculture, stating that understanding soil dynamics can help in “sustaining agricultural productivity” and driving “advancements in agricultural practices.” This directly relates to ensuring food security.
• SDG 9: Industry, Innovation, and Infrastructure: The research has significant implications for geotechnical engineering and construction. The article highlights that the findings can help engineers “design more resilient structures that withstand the unpredictable nature of soil shrinkage,” which aligns with the goal of building resilient infrastructure.
• SDG 11: Sustainable Cities and Communities: By providing knowledge to build more stable and resilient structures on kaolin-rich soils, the research contributes to making human settlements safer. This is particularly relevant for managing the stability of buildings and infrastructure in urban and rural areas.
• SDG 13: Climate Action: The article explicitly links the research to climate change, noting that as it “intensifies, fluctuations in moisture availability will become more pronounced.” Understanding soil behavior is presented as a “critical step toward unraveling the complexities of soil behavior” in response to “climate-related challenges.”
• SDG 15: Life on Land: The study’s focus on soil behavior is directly tied to environmental management and ecosystem health. The article mentions the importance of “soil conservation,” “maintaining ecosystem health,” and contributing to “broader ecological stability” and “overall ecosystem welfare,” which are central to protecting terrestrial ecosystems.

2. What specific targets under those SDGs can be identified based on the article’s content?

• Target 2.4: By 2030, ensure sustainable food production systems and implement resilient agricultural practices that increase productivity and production, that help maintain ecosystems, that strengthen capacity for adaptation to climate change, extreme weather, drought, flooding and other disasters and that progressively improve land and soil quality. The article’s focus on soil moisture retention and stability is fundamental to developing such resilient agricultural practices.
• Target 9.1: Develop quality, reliable, sustainable and resilient infrastructure, including regional and transborder infrastructure, to support economic development and human well-being. The research provides practical insights for geotechnical engineers to “design more resilient structures,” directly contributing to this target.
• Target 11.5: By 2030, significantly reduce the number of deaths and the number of people affected and substantially decrease the direct economic losses relative to global gross domestic product caused by disasters, including water-related disasters, with a focus on protecting the poor and people in vulnerable situations. Understanding soil shrinkage helps in constructing buildings and infrastructure that can better withstand environmental stresses like drought cycles, thus enhancing community resilience.
• Target 13.1: Strengthen resilience and adaptive capacity to climate-related hazards and natural disasters in all countries. The study’s findings on how soil behaves under different moisture conditions (e.g., drought) provide crucial knowledge for adapting infrastructure and agricultural systems to the impacts of climate change.
• Target 15.3: By 2030, combat desertification, restore degraded land and soil, including land affected by desertification, drought and floods, and strive to achieve a land degradation-neutral world. The research on soil-water characteristics and shrinkage is essential for understanding and managing soil health, which is a key component of restoring degraded land and preventing desertification.

3. Are there any indicators mentioned or implied in the article that can be used to measure progress towards the identified targets?

Yes, the article discusses specific scientific measurements that serve as direct indicators for assessing soil health and stability, which are crucial for tracking progress towards the identified targets.

• Soil-Water Characteristic Curve (SWCC): This is explicitly mentioned as a key measurement in the study. The SWCC illustrates how a soil’s water retention changes with suction. It serves as a direct indicator of a soil’s ability to retain moisture, which is vital for agricultural productivity (Target 2.4) and ecosystem health (Target 15.3).
• Shrinkage Curve: The article identifies the shrinkage curve as the other primary measurement. It provides “insights on how soil volume changes with moisture loss.” This curve is a direct indicator of soil stability, which is critical for designing resilient infrastructure and buildings (Targets 9.1 and 11.5).
• Soil Volumetric Changes: This is an implied indicator directly measured by the shrinkage curve. Monitoring changes in soil volume under different drying conditions helps predict soil stability and its potential impact on structures and ecosystems.
• Soil Moisture Content: The study revolves around how kaolin behaves under different “moisture conditions” and “moisture levels.” Soil moisture content is a fundamental indicator used to assess conditions for agriculture, ecosystem function, and the risk of soil shrinkage or swelling.

4. Summary Table of SDGs, Targets, and Indicators

Source: bioengineer.org