Is just considering texture enough to define compaction on the basis of soil density?

Abstract

The bulk density values indicative of compaction in clayey soils correspond to a wide range of values (1.30-1.47 Mg m-3), due to the diverse types of soil management. Our hypothesis is that if we consider bulk density values within similar management groups (those that fall to the ground and those that do not fall), the values will be more accurate within each management group. Our objective in this work was to analyze using the concepts of (Yates & Cochran, 1938; Whitehead, 2002) what is a suitable statistical way of grouping these results to reach a consensus regarding a tested hypothesis, the greatest number of density values surveyed between 1977 and 2021, considered for the study of compaction in clayey Oxisols under different managements, to verify whether our hypothesis will be confirmed. We selected 1,521 studies with bulk densities in the literature, corresponding to 44 years (1977 and 2021), which were analyzed by a statistical technique that integrates the results of two or more independent studies on the same subject and combines them into a summary measure (portion forestry). From the data collected in the literature, it was possible to separate two groups of bulk density and management in clayey soils indicative of compaction: the managements that perform little or no manipulation of the soil, such as pasture and no-tillage, densities between 1.41-1.45 Mg.m-3 (average 1.43 Mg m-3), and for the others, such as conventional plowing and minimum tillage, soil densities between 1.31-1.38 Mg.m-3 (average 1.35 Mg m-3). Finally, we conclude that compaction must be analyzed considering the texture and type of soil management.