Impact of freeze–thaw cycling on the stability and turnover of black soil aggregates

Geoderma, Год журнала: 2024, Номер 449, С. 117004 - 117004

Опубликована: Авг. 15, 2024

During freeze–thaw cycling, aggregates undergo a dynamic change in breakdown–formation (turnover), however, how the turnover occurs between of various particle sizes is not clear. To clarify influence cycling on changes size soil aggregates, from Black Soil Region Northeast China were selected as research objects. The study conducted situ monitoring experiments, innovatively applying rare earth oxide (REO) tracer method to natural conditions cycles (autumn period, freezing and spring period), accurately tracking paths quantifying rates sizes. results revealed that total value formation 2–5 mm 0.25–2 increased during autumn period. number accumulated snowfall significantly positively correlated with aggregate stability, an increase resulting proportion > 0.25 mm, which improved stability. In addition, breakdown path macro-aggregates moisture was negatively decrease percentage resulted can provide reference understanding for effects structure black theoretical basis improving quality arable land.

Язык: Английский

Optimal Level of Straw Addition After the Autumn Harvest for Black Soil Aggregate Stability

Land Degradation and Development, Год журнала: 2025, Номер unknown

Опубликована: Фев. 10, 2025

ABSTRACT In Northeast China, straw residues are integrated into fields to improve the soil structure and fertility after autumn harvest. However, optimal amount of addition is unclear. To determine whether an increase in correlated with aggregate stability, study focused on black cropland was conducted through field incubation experiment (lasting 150 days) during seasonal freeze–thaw periods, implemented six different treatments: CK (0%), SA1 (1%, i.e., 10 g per kg soil), SA3 (3%), SA5 (5%), SA7 (7%), SA9 (9%). The results revealed that under conditions, stability significantly increased only when ≥ 5%. At this level, enhanced two ways. First, decomposition SOC content, which serves as a binding substance for aggregates promotes formation > 0.25 mm. Second, particles combined form straw‐soil composite macro‐aggregates exhibited high water stability. not positively amount. This because 5% sufficient reach carbon saturation, content showed no significant change further increasing addition. Moreover, excessive led nitrogen limitation slowed down rate but also wasted resources. Therefore, improving These findings provide theoretical basis how rational design return measures, thereby conditions spring sowing seedling emergence China.

Язык: Английский

Chronosequence changes in soil microbes under Populus simonii × P. nigra stands: Implications for soil health restoration in Mollisols

Applied Soil Ecology, Год журнала: 2024, Номер 206, С. 105826 - 105826

Опубликована: Дек. 12, 2024

Язык: Английский