Conversion of forest to agricultural land for maize cultivation is known to negatively affect soil fertility.
However, limited knowledge is available of the impact on aggregate stability and interconnected soil
properties. The aims of the present study were to (1) quantify soil aggregate stability, (2) assess aggregate
stability changes after land use change, and (3) determine the interactions of aggregate stability with
clay, soil organic carbon (SOC), exchangeable Ca2+ and Mg2+, and soil erosion rates. The topsoils of three
soil types in Northwest Vietnam were analyzed in consequences (0–18 y after land use change from
forest to continuous maize) by two methods: Wet sieving and sonication. By differentiation of these
aggregate stability measurements, the impact of both methods on aggregate size distribution could be
quantified separately and compared. The sonication method indicated a more homogeneous
dis-aggregation whereas the wet sieving method was more suitable to detect low aggregate stabilities.
Soil aggregate stability declined simultaneous with a decrease of SOC and exchangeable Ca2+ and Mg2+,
which both declined with increasing time since land use change. The Ali sol and Luvisol consequences
were 1.9 times more stable under primary forest than under maize (shown by sonication) whereas the
Solver consequence was 2.5 times more stable under primary forest (shown by wet sieving). Over
the 18 y consequence the topsoil's had 1.6 kg m2 lower SOC and 3.2 g kg1 lower Ca2+ contents. This
study highlights the destabilization of soil in interaction with a degradation of relevant chemical soil
properties with differentiated aggregate stability methods.