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Soil erosion exacerbates the reduction of soil organic matter (SOM) and destruction of soil physical structure in agricultural systems, which seriously threatens agricultural ecological environment and global sustainable agriculture development. Owing to rich SOM and nutrients of woody peat results in it's widely applied in degraded soil for improving land productivity. But how the impacted of woody peat addition on crop growth and soil organic matter (SOM) in different textured degenerated erodible soils are not well understood. Here, along the latitudinal gradient from north to south of China, four typical regional soils collected in Northeast (black soil), Northwest (loessial soil), Central (lou soil) and South (red soil) of China, where suffered strongly soil erosion. Soil clay content was 37.0%, 16.9%, 29.6%, and 38.5% for the black, loessial, lou, and red soils, respectively. We conducted a plot incubation experiment in a fully ventilated, rainproof outdoor greenhouse for planting wheat (Triticum aestivum L.). The study is aimed to investigate the response of different texture eroded soil to crop growth and physiology, soil evaporation and soil organic matter after woody peat addition. Eight treatments have been designed for four soils with two groups. (i) the control group with no woody peat addition, B0, H0, L0 and R0; (ii) woody peat addition group, BW, HW, LW and RW. Overall, the SOM concentration altered wheat growth characteristic and grain yield in the four typical erosion degraded soils. The highest grain yield of winter wheat is 6.5 ± 1.3 g per plot in B0 and 6.5 ± 1.1 g per plot in BW, and the lowest is 0.4 ± 0.1 g per plot in R0 in red soil. But woody peat addition increased the wheat yield or yield variation, the wheat gain yield increased four times with woody peat addition (RW) than control (R0) in red soil. In addition, the results revealed that the SOM content were increased in black soil by 40.4%, in loessial soil by 40.0%, in lou soil by 101.3%, and in red soil by 94.6% when compared to the control treatments at harvest. From sowing to harvest, SOM decreased by 5.1 ± 1.8 g kg-1 (black soil), 9.9 ± 0.9 g kg-1 (loessial soil), 7.6 ± 1.8 g kg-1 (lou soil), and 6.2 ± 1.0 g kg-1 (red soil) in the soils with woody peat addition. Without woody peat addition, SOM decreased by 5.6 g kg-1 (black soil), 4.7 g kg-1 (lou soil), and 0.6 g kg-1 (red soil), but increased by 0.4 g kg-1 in loessial soil. In conclusion, woody peat addition resulted in wheat yield increasing in the degenerated soils, but it's significant in the red soil with adequate nutrient supply and increased soil acid buffering capacity. Woody peat addition increased the SOM concentration in the four degenerated soils, but a faster decreasing rate of the ΔSOM in coarse-textured loessial soil than others medium-fine texture soils. Therefore, appropriate woody peat application and clay content is more conducive to the protection of SOM. More deeply research should have been focused on the impact of woody peat addition in coarse-textured soil on the soil environment (such as the clay type, content, and soil priming effect, etc.). • Woody peat was a promising soil amendment. • Increased SOM in the four typical eroded agricultural soils with woody peat addition. • Faster turnover rate of SOM was in coarse-textured erodible soil than medium-fine textured soil. [ABSTRACT FROM AUTHOR]

• Alkaline coarse-textured soils had larger PFPs' density than acid fine-textured soils. • Longer history of PSVP had significant contribution to the density of soil PFPs. • Soil physical and P sorption properties significantly influenced the occurrence of PFPs. • PFPs had significant impact on leaching of dissolved reactive P from PSVP soils. • Particulate P leaching from PSVP soils mostly occurred through soil matrix. Despite its importance, the contribution of preferential flow pathways (PFPs) to subsurface phosphorus (P) leaching from heavily-fertilized plastic shed vegetable production (PSVP) soils in China has remained unexplored. To investigate this, five acid fine-textured Orthic Anthrosols and six alkaline coarse-textured Ustic Cambosols intact soil columns (20 cm depth and 15 cm diameter), from two typical PSVP systems in Jiangsu Province, Southeast China, were subjected to six leaching experiments with collection of effluents over 24 h. Leachate samples were analyzed for their concentrations of particulate P (PP) and dissolved reactive P (DRP). Finally, soil columns were photographed for their 2D distribution of PFPs both vertically (0−20 cm) and horizontally at 5 cm intervals after the application of dye tracer (Brilliant Blue). Overall, alkaline coarse-textured Ustic Cambosols with longer history of PSVP had larger PFPs' volumes than acid fine-textured Orthic Anthrosols with vertical (0−20 cm) values ranging from 812 to 1260 cm2 and 623 to 1104 cm2, respectively. Of soil properties, pH and sand content had significant positive correlations with PFPs' density (p < 0.05). Whereas, soil contents of clay and oxalate extractable Al and Fe had significant negative correlations with PFPs' density (p < 0.05). In terms of subsurface P mobilization, preferential water flow had significant impact on DRP leaching (p < 0.05). In contrast, leachate PP concentrations had no significant relationships with both vertical and horizontal PFPs, indicating that PP leaching might occur mostly through soil matrix. However, field assays are still essential for better understanding of P leaching in relation to PFPs through taking into account the soil physiochemical properties and agricultural management. [ABSTRACT FROM AUTHOR]

• Soil total P and colloidal P content vary with rice-fallow seasons and soil types. • No-till with straw return can significantly increase soil total P and soil available P. • No-till combined with straw return is an effective way to reduce soil colloidal P content. Colloidal phosphorus (P) migration has been confirmed to be an important pathway for P loss in farmland. A field experiment was conducted with four treatments and three replications: conventional tillage/straw harvest (CH), conventional tillage/straw return (CR), no-till/straw harvest (NH), and no-till/straw return (NR) to clarify the effect of conservation agricultural practices on concentration of soil total P, available P, P stocks, and colloidal P during a 2-year rice-growing season in Zhejiang Province in China. The results showed that the soil total P and available P content increased significantly at the end of the two years compared with that before the experiment (P < 0.05), by 18.80–38.90 mg kg–1 and 1.12–1.55 mg kg–1 in clay soil, and by 20.70–35.70 mg kg–1 and 1.81–2.17 mg kg–1 in loam soil. While the total P accumulation in both soil types mainly occurred during the rice-growing season. The highest P stocks (293.90 and 136.80 g m−2) in the two soils were found in the NR treatment. In contrast, soil colloidal P significantly declined during the two-year rice-fallow period. The CR and NR treatments resulted in the lowest colloidal P contents (6.1 mg kg–1 and 3.6 mg kg–1) and accounted for the lowest percentage of total P (0.6% and 0.8%) in clay loam and loam soils, respectively. Straw return/harvest and no-till/till had an interactive effect on the soil colloidal P content. The combination of no-till and straw return is an effective way to reduce loss potential of soil colloidal P in a rice-fallow system but varies by soil texture. [ABSTRACT FROM AUTHOR]