Soil quality

Soil quality refers to the condition of soil based on its capacity to perform ecosystem services that meet the needs of human and non-human life.^[1][2][3][4]

Testing soil fertility

Soil quality reflects how well a soil performs the functions of maintaining biodiversity and productivity, partitioning water and solute flow, filtering and buffering, nutrient cycling, and providing support for plants and other structures. Soil management has a major impact on soil quality.

Soil quality relates to soil functions. Unlike water or air, for which established standards have been set, soil quality is difficult to define or quantify.

Indicators of soil quality

Soil quality can be evaluated using the Soil Management Assessment Framework.^[5] Soil quality in agricultural terms is measured on a scale of soil value (Bodenwertzahl) in Germany.^[6]

Soil quality is primarily measured by chemical, physical, and biological indicators because soil function cannot easily be measured directly.^[7] Each of these categories comprises several indicators that provide insight into overall soil quality. There are very few soil quality monitoring systems that can provide near real-time information on these indicators but almost all of these systems are currently reported only to the research level. ^[8]

Physical

The physical category of soil quality indicators consists of tests that measure soil texture, bulk density, porosity, water content at saturation, aggregate stability, penetration resistance, and more.^[9] These measures provide hydrological information, such the level of water infiltration and water availability to plants.

Chemical

Chemical indicators include pH and nutrient levels.^[10] A typical soil test only evaluates chemical soil properties.^[7]

Biological

Biological measures include diversity of soil organisms and fungi.

The movement and biological functions of soil organisms (including earthworms, millipedes, centipedes, ants, and spiders) impact soil processes such as the regulation of soil structure, degradation of contaminants, and nutrient cycling.^[11]

References

1. Johnson, D. L.; Ambrose, S. H.; Bassett, T. J.; Bowen, M. L.; Crummey, D. E.; Isaacson, J. S.; Johnson, D. N.; Lamb, P.; Saul, M.; Winter-Nelson, A. E. (1997). "Meanings of Environmental Terms". Journal of Environmental Quality. 26 (3): 581. doi:10.2134/jeq1997.00472425002600030002x.
2. Karlen, D. L.; Mausbach, M. J.; Doran, J. W.; Cline, R. G.; Harris, R. F.; Schuman, G. E. (1997). "Soil Quality: A Concept, Definition, and Framework for Evaluation (A Guest Editorial)". Soil Science Society of America Journal. 61 (1): 4–10. Bibcode:1997SSASJ..61....4K. doi:10.2136/sssaj1997.03615995006100010001x. Retrieved 21 June 2017.
3. USDA NRCS. "Soil Quality: Basics: Definitions". soilquality.org. Retrieved 21 June 2017.
4. Tóth, G., Stolbovoy, V. and Montanarella, 2007. "Soil Quality and Sustainability Evaluation - An integrated approach to support soil-related policies of the European Union Archived 2013-10-29 at the Wayback Machine", EUR 22721 EN. 40 pp. Office for Official Publications of the European Communities, Luxembourg. ISBN 978-92-79-05250-7.
5. Cherubin, Maurício Roberto; Tormena, Cássio Antônio; Karlen, Douglas L.; Cherubin, Maurício Roberto; Tormena, Cássio Antônio; Karlen, Douglas L. (2017). "Soil Quality Evaluation Using the Soil Management Assessment Framework (SMAF) in Brazilian Oxisols with Contrasting Texture". Revista Brasileira de Ciência do Solo. 41. doi:10.1590/18069657rbcs20160148. ISSN 0100-0683.
6. Hoffmann, Carsten; Schulz, Sina; Eberhardt, Einar; Grosse, Meike; Stein, Susanne; Specka, Xenia; Svoboda, Nikolai; Heinrich, Uwe (2019). "Data Standards for Soil- and Agricultural Research". doi:10.20387/BONARES-ARM4-66M2. {{cite journal}}: Cite journal requires |journal= (help)
7. Doran, John W. (1997). Methods for Assessing Soil Quality (49 ed.). Soil Science Society of America. ISBN 9780891188261.
8. M. Sophocleous et al., "A Stand-Alone, In Situ, Soil Quality Sensing System for Precision Agriculture," in IEEE Transactions on AgriFood Electronics, doi: 10.1109/TAFE.2024.3351953.
9. Rodriguez, Leonardo; Suárez, Juan Carlos; Pulleman, Mirjam; Guaca, Lised; Rico, Adrian; Romero, Miguel; Quintero, Marcela; Lavelle, Patrick (2021). "Agroforestry systems in the Colombian Amazon improve the provision of soil ecosystem services". Applied Soil Ecology. 164: 103933. doi:10.1016/j.apsoil.2021.103933. S2CID 233583678.
10. Bravo‐Medina, C.; Goyes‐Vera, F.; Arteaga‐Crespo, Y.; García‐Quintana, Y.; Changoluisa, D. (2021-04-15). "A soil quality index for seven productive landscapes in the Andean‐Amazonian foothills of Ecuador". Land Degradation & Development. 32 (6): 2226–2241. doi:10.1002/ldr.3897. ISSN 1085-3278. S2CID 233974087.
11. Ruiz N, Lavelle P, Jiménez J. 2008. Soil macrofauna field manual. Food and Agriculture Organization. https://www.fao.org/3/i0211e/i0211e00.htm