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Context. In Sweden, mixtures of 80-85% ground limestone and 15-20% slaked lime (hereafter, 'structure lime') are used in subsidised environmental schemes to improve aggregate stability and mitigate phosphorus losses on clay soils. Aims. This study investigated different rates of structure lime application and soil variables on aggregate stability on clay soils, and whether soil properties can predict aggregate stability following structure liming. Methods. Increasing application rates of 0-16 t [ha.sup.-1] of structure lime (SL0, SL4, SL8 and SL16) were tested in 30 field trials in Sweden. Soil aggregates (2-5 mm) were collected 1 year after liming and subjected to two rainfall events in a rain simulator. Key results. Leachate turbidity after the second simulated rainfall event decreased significantly (13% and 20%, respectively, in SL8 and SL16) compared with SL0, indicating improved aggregate stability. There was a near-significant interaction (P = 0.056) between treatment and trial. Grouping by initial [Please download the PDF to view the mathematical expression] (range 6.2-8.3), clay content (10-61%), soil organic matter content (SOM, 2.2-7.1) and clay mineralogy (SmV index, 0.2-3.8) revealed different effects on turbidity. Discriminant analysis of soil characteristics and four tillage variables correctly classified the outcome for 27 of the 30 trial sites. Conclusions. Results show that structure liming can improve aggregate stability l year after liming, and can thereby prevent particulate P losses from soils with high clay and SOM content, low SmV index and low initial pH. The discriminant analysis also showed the importance of tillage for the outcome of structure liming. Implications. Clay soil characteristics such as SOM and pH significantly affected aggregrate stability after structure liming. Keywords: aggregate stability, clay content, clay mineralogy, pH, phosphorus losses, SOM, structure lime, turbidity., Introduction Acidification of soils is a process with both natural and human-made causes (Filipek 2011). Liming is a well-established global practice to counteract acidification and ameliorate acidic soils (Frank et [...]

Liming before cultivation of sugar beets is favourable even on alkaline soils but knowledge of response in other crops is lacking. Therefore, effects of ground limestone (GL) and structure lime (SL1 slaked lime or SL2 mix of ground limestone and slaked lime) were evaluated in southern Sweden on soil structure, growth and nutrient concentration in barley under four fertilisation strategies 1.5–2 years after application. All lime products increased aggregate stability, but with variations between locations. A lower proportion of large aggregates was found in both limed treatments, and a higher proportion of small aggregates in SL. In barley, grain yield was unaffected while shoot numbers and biomass in first node stage increased for GL and biomass increased further for SL. Structure lime increased potassium concentration in plants in first node stage, due to more potassium in the product. Both lime types increased molybdenum concentration. Ground limestone reduced zinc concentration compared with no liming. Finer seedbed tilth and increased aggregate stability may explain increased biomass for GL. Higher potassium content in SL might be a further explanation. No interactions between liming and fertilisation were found. In conclusion, on the soil types studied, no change of fertilisation strategy is needed due to liming. [ABSTRACT FROM AUTHOR]