Mixture of N2-fixing tree species promotes organic phosphorus accumulation and transformation in topsoil aggregates in a degraded karst region of subtropical China

Differential responses and mechanistic controls of soil phosphorus transformation in Eucalyptus plantations with N fertilization and introduced N2‐fixing tree species

“…3b). Consistent with previous studies (Huang et al, 2014;Li et al, 2022), the enhanced abundances of total microbes including bacteria, fungi, and AMF with introduced N 2 -fixing tree species were closely relation to soil nutrient status and stoichiometry (Figs 2,3,S4b). Generally, introduced N 2 -fixing tree species favors bacterial growth because N-rich litterfall is easily decomposed by bacteria (Wardle et al, 2003;Viketoft et al, 2009).…”

“…Generally, introduced N 2 ‐fixing tree species favors bacterial growth because N‐rich litterfall is easily decomposed by bacteria (Wardle et al ., 2003; Viketoft et al ., 2009). A diversity of litter inputs with introduced N 2 ‐fixing tree species may also facilitate microbial diversity including the abundance of fungi and AMF (Li et al ., 2022). In addition, introduced N 2 ‐fixing tree species could increase soil TN content by directly fixing atmospheric‐N, leading to soil nutrient imbalance with higher N : P ratio (Table 1).…”

“…Moreover, the dissolutions of occluded P pool under the N‐fixer treatment may be directly transferred into the relatively labile Po pools (Liu et al ., 2021b). In addition, N 2 ‐fixing tree species may absorb P from the deeper soils (> 20 cm), promoting Po accumulation in the surface soils (< 20 cm) through faster turnover of litterfall (Li et al ., 2022). N 2 ‐fixing tree species may also reduce the leaching loss of Po through changing soil physical and chemical properties and stimulating microbial P assimilation (Nesper et al ., 2015).…”

Rare microbial taxa as the major drivers of nutrient acquisition under moss biocrusts in karst area

“…The difference made site A susceptible to shade from forests and site C susceptible to direct sunlight, resulting in varying soil moisture and nutrient conditions at the two sites. Soil nutrients have a significant influence on enzyme activities ( Meier et al, 2020 ; Li et al, 2022 ). The scatter plot with eco-enzymatic stoichiometry reveals that microbial limitations in C&P, and C&N were prevalent across all locations ( Figure 1B ).…”

An assessment of various pools of organic phosphorus distributed in soil aggregates as affected by long‐term P fertilization regimes

“…It may cause by the mobilization of Po through microbial mineralization because TN, SOC and phosphatase activity can accelerate the microbial mineralization rates of Po and mobilize more P from nonlabile Po pool, leading to an increase in labile Po in soil aggregates (Ahmed et al, 2019; Brucker et al, 2020; Li et al, 2021; Wang, Xiaomei, et al, 2022). In addition, the negative correlations between soil pH and labile Po in soil aggregates (Figure 4a) may indicate that soil pH can regulate the interaction between Po compounds and clay minerals by affecting the cation exchange sites (Hou et al, 2018; Li, Yeming, et al, 2022) because decreased soil pH can promote the release of P held in Ca–Pi through stimulating the soil acidification‐induced dissolution of Ca–Pi in the context of alkaline soils (Andersson et al, 2015). Furthermore, we found a significant accumulation of labile Po content in large (>250 μm) aggregate than the other size aggregate classes (Figure 2a), mainly attributed to a greater amount of SOC content after long‐term fertilization practices (Figure 2a and Table 1) because large aggregates can supply a mechanism for the protection of soil organic matter (Ahmed et al, 2016) that can ensure effective supply of available Po.…”