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Herbal leys (multispecies swards) can potentially deliver greater agronomic and environmental benefits than conventional grass-clover swards in grazed agroecosystems. However, despite their popularity in agri-environment schemes, little is known about the effect of herbal leys on soil physical (e.g., porosity), chemical (e.g., carbon), and biological (e.g., soil fauna) characteristics. In the UK, a 2-ha replicated-field experiment utilising a herbal or grass-clover ley (n = 3 per sward) aimed to investigate the effect of sward type on soil quality. Each sward was rotationally grazed by weaned lambs (3.2 LU ha−1) over two grazing seasons, with soil physiochemical and biological characteristics assessed after 2-years using techniques such as X-ray micro-Computed Tomography (µCT) and microbial shallow shotgun sequencing. Soil chemical characteristics (e.g., pH) were unaffected by sward type. Similarly, topsoil (0–10 cm) organic carbon stocks measured after 2-years did not differ between the herbal (26.1 ± 1.1 t C ha−1) and grass-clover ley (25.7 ± 1.1 t C ha−1). X-ray µCT analysis revealed greater pore connectivity (Euler number) in grass-clover ley intact soil cores (0–10 cm depth, 7.5 cm width) than herbal ley cores dominated by Plantago lanceolata (p = 0.008). However, there was no sward-type difference in aggregate stability or general pore characteristics, determined using X-ray µCT, in air-dried 4 mm aggregates obtained from 0–5 or 5–10 cm depth, nor did sward type affect earthworm abundance, microbial community composition or the functional gene profile. This study is the first to explore the effects of a commercial herbal ley on physical, chemical, and biological soil quality indicators in a rotationally grazed sheep pasture. While no improvements in soil quality indicators were observed after 2-years, these findings have significant implications for agri-environment schemes promoting herbal leys to achieve soil quality and sustainability, with further research needed to optimise the seed mixture and management regime to deliver greater long-term below-ground ecosystem service benefits. [Display omitted] • Increasing grassland species richness can improve soil quality. • X-ray µCT showed greatest pore connectivity in intact grass-clover ley cores. • Sward type did not affect soil physical or chemical characteristics. • Sward diversity did not affect earthworm abundance or microbial community composition. [ABSTRACT FROM AUTHOR]

Biochar can enhance organic carbon storage and mitigate the adverse effects of pesticides in the soil. However, the mechanisms by which field-aging affects the impacts of biochar on herbicide behavior and the composition of microbial communities in the soil remain unclear. This study aimed to investigate the influences of aged and fresh biochar on herbicide behavior and microbial community structure in the soil. Herein, with 14C-labeled technology, aged treatment (soil amended with field-aged biochar), fresh treatment (soil amended with fresh biochar), and control (soil without biochar) were installed to evaluate their treatment capacities. The results showed that the average leaching out and mineralization of simazine in the aged treatment were significantly higher by 4.8% and 1.66% (P < 0.05) compared with the fresh treatment. Relative to the control, the pesticide was significantly adsorbed (P < 0.05) in the aged treatment. The abundance of arbuscular mycorrhizal fungi (AMF) significantly increased by 1.03 and 1.16-fold , whereas fungi increased dramatically by 1.02-fold and decreased by 1.21-fold in the aged and fresh treatments, respectively (P < 0.05). In addition, eukaryotes were effectively reduced by 1.02 and 1.14-fold in these treatments, respectively (P < 0.05). This study suggests that field aging can undermine the impacts of biochar on pesticides and modify the microbial community structure in the soil environment. [Display omitted] • The treatment performance of aged and fresh biochar in pesticide-polluted soil was evaluated. • Field-aging lowered the biochar adsorption capacity for simazine in the soil environment. • Fresh biochar increased arbuscular mycorrhizal fungi but reduced eukaryotes in the soil environment. • Fresh biochar significantly lessened the leaching and decomposition of simazine in the soil. [ABSTRACT FROM AUTHOR]

Biochar can enhance organic carbon storage and mitigate the adverse effects of pesticides in the soil. However, the mechanisms by which field-aging affects the impacts of biochar on herbicide behavior and the composition of microbial communities in the soil remain unclear. This study aimed to investigate the influences of aged and fresh biochar on herbicide behavior and microbial community structure in the soil. Herein, with 14C-labeled technology, aged treatment (soil amended with field-aged biochar), fresh treatment (soil amended with fresh biochar), and control (soil without biochar) were installed to evaluate their treatment capacities. The results showed that the average leaching out and mineralization of simazine in the aged treatment were significantly higher by 4.8% and 1.66% (P < 0.05) compared with the fresh treatment. Relative to the control, the pesticide was significantly adsorbed (P < 0.05) in the aged treatment. The abundance of arbuscular mycorrhizal fungi (AMF) significantly increased by 1.03 and 1.16-fold , whereas fungi increased dramatically by 1.02-fold and decreased by 1.21-fold in the aged and fresh treatments, respectively (P < 0.05). In addition, eukaryotes were effectively reduced by 1.02 and 1.14-fold in these treatments, respectively (P < 0.05). This study suggests that field aging can undermine the impacts of biochar on pesticides and modify the microbial community structure in the soil environment. [Display omitted] • The treatment performance of aged and fresh biochar in pesticide-polluted soil was evaluated. • Field-aging lowered the biochar adsorption capacity for simazine in the soil environment. • Fresh biochar increased arbuscular mycorrhizal fungi but reduced eukaryotes in the soil environment. • Fresh biochar significantly lessened the leaching and decomposition of simazine in the soil. [ABSTRACT FROM AUTHOR]