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This study investigates the utility of plant δ¹3C natural labeling in predicting the impacts of environmental shifts on carbon cycling within ecosystems, particularly focusing on paddy fields treated with maize (Zea mays L.) residues and biochar. Specifically, it examines how soil δ¹3C and the sources of soil organic carbon (SOC), respond in paddy fields (which cultivate C3 plants like rice) when amended with maize residues, maize biochar, and silica‐enriched biochar (derived from C4 plants). Conducted in the Fuzhou paddy fields, the experiment included control groups and treatment groups with maize residue (4 t ha⁻¹), maize biochar (4 t ha⁻¹), and silicon‐modified maize biochar (4 t ha⁻¹) during both the early and late rice growth periods. The results indicate that all soil treatments increased soil δ¹3C. The application of maize residues notably affected the δ¹3C of the upper soil profile (0–15 cm) differently from the deeper layers (15–30 cm), and it increased soil organic C more than biochar or silicon‐modified maize biochar. Soil available P (AP) and pH emerged as significant factors linking δ¹3C, influencing rice yield through changes in soil physicochemical properties. Unlike maize residues, which reduced rice yields, applications of biochar and silicon‐modified maize biochar increased rice yields. The latter, which was particularly effective in lowering SOC decomposition rates and addressing rice's silica needs, emerged as the preferred option. The study highlights maize biochar and silicon‐modified maize biochar as sustainable alternatives to maize residues for rice cultivation, enhancing soil fertility, carbon pool stability, and yields. Core Ideas: New management of crop residues to improve crop soil quality in paddy fields is studied.New management of crop residues to improve rice yield is studied.The suitability of use of δ13C labeling methods for this type of research is determined.The relationship between diverse soil physicochemical properties with changes in soil organic carbon contents and quality is studied.The use of excessive industrial fertilizers should be avoided. [ABSTRACT FROM AUTHOR]

Soil phosphorus (P) availability is a crucial factor determining primary productivity in terrestrial ecosystem. Plant functional traits and microbes under P‐deficient conditions can respond positively to increase soil P bioavailability. Whether and/or how the fine‐root traits (FRTs) of deep‐rooted desert species affect the rhizosphere and bulk soil community of phoD‐harbouring bacteria and thus improve the availability of soil P, however, remains unclear.We conducted a three‐year artificial outdoor pot experiment of P supply using Alhagi sparsifolia Shap. (hereafter Alhagi) to address this gap. Fine‐root samples from 1‐ and 3‐year‐old Alhagi seedlings and samples of the rhizospheres and bulk soil were collected. High‐throughput sequencing, sequential extraction and root system scanning were used to determine soil phoD‐harbouring bacteria community, Hedley‐P fractions and the FRTs.Fine‐root surface area (RSA), specific root length, foliar Mn concentration (indicating the quantities of root carboxylates that are released) and acid phosphatase (APase) activity were significantly higher in the no‐P supply compared with the high‐P supply conditions. APase activity was significantly higher by 27%, but the foliar Mn concentration was remarkably lower by 26%, in the 3‐ than the 1‐year‐old seedlings. The rhizospheric concentrations of labile P, moderately labile P, inorganic P and organic P in the no‐P supply condition were 5%, 11%, 10% and 21% higher, respectively, in the 3‐ than the 1‐year‐old seedlings. RSA and the foliar Mn concentration were dominated root predictors for the rhizospheric phoD‐harbouring bacteria community for the 1‐year‐old seedlings, whereas fine‐root P concentration was the dominated root predictor for the rhizospheric and bulk soil phoD‐harbouring bacteria communities for the 3‐year‐old seedlings. Soil water content, as the most dominant soil factor driving the variation of phoD‐harbouring bacteria community, notably could not be ignored. FRTs were the main factors that directly and positively determined rhizospheric phoD‐harbouring bacteria community and thus influenced soil P availability, but bulk soil phoD‐harbouring bacteria community were dominated by inorganic P concentration. The importance of fine‐root morphological traits to soil P availability gradually increased as the plants grew.Overall, our results emphasize the significance of rhizospheric phoD‐harbouring bacteria determined by the effect of FRTs on the bioavailability of soil P. Read the free Plain Language Summary for this article on the Journal blog. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Coastal‐wetlands play a crucial role as carbon (C) reservoirs on Earth due to their C pool composition and functional sink, making them significant for mitigating global climate change. However, due to the development and utilization of wetland resources, many wetlands have been transformed into other land‐use types. The current study focuses on the alterations in soil organic‐C (SOC) in coastal‐wetlands following reclamation into aquaculture ponds. We conducted sampling at 11 different coastal‐wetlands along the tropical to temperate regions of the China coast. Each site included two community types, one with solely native species (Suaeda salsa, Phragmites australis and Mangroves) and the other with an adjacent reclaimed aquaculture pond. Across these 11 locations we compared SOC stock, active OC fractions, and soil physicochemical properties between coastal wetlands and aquaculture ponds. We observed that different soil uses, sampling sites, and their interaction had significant effects on SOC and its stock (p <.05). Reclamation significantly declined SOC concentration at depths of 0–15 cm and 15–30 cm by 35.5% and 30.3%, respectively, and also decreased SOC stock at 0–15 cm and 15–30 cm depths by 29.1% and 37.9%, respectively. Similar trends were evident for SOC stock, labile organic‐C, dissolved organic‐C and microbial biomass organic‐C concentrations (p <.05), indicating soil C‐destabilization and losses from soil following conversion. Soils in aquaculture ponds exhibited higher bulk density (BD; 11.3%) and lower levels of salinity (61.0%), soil water content (SWC; 11.7%), total nitrogen (TN) concentration (23.8%) and available‐nitrogen concentration (37.7%; p <.05) than coastal‐wetlands. Redundancy‐analysis revealed that pH, BD and TN concentration were the key variables most linked with temporal variations in SOC fractions and stock between two land use types. This study provides a theoretical basis for the rational utilization and management of wetland resources, the achievement of an environment‐friendly society, and the preservation of multiple service functions within wetland ecosystems. [ABSTRACT FROM AUTHOR]

Understanding the influence of afforestation on soil microorganisms, the major drivers of soil processes, is essential for maintaining soil health and sustainability. However, in a desert‐oasis ecotone, variations in the microbial community along shrub afforestation years remain unclear. We conducted a metagenomic analysis to study the temporal changes in microbial community structure in 0–100 cm soil following 3‐, 7‐, and 10‐year afforestation of Tamarix ramosissima Ledeb. on the southern edge of the Taklimakan Desert. Compared to the unreclaimed desert land, in 3‐year or 7‐year stands, soil organic carbon (SOC), nitrate nitrogen, available phosphorus and potassium (AK) contents significantly increased on average by 60%, 852%, 72%, and 299%, respectively. Soil archaeal and bacterial community composition were significantly affected by afforestation; their α‐diversity increased on average by 5.9% and 11.1%, respectively, after afforestation, showing a unimodal pattern along afforestation years. In contrast, fungal α‐diversity and community composition did not show significant variation over the afforestation period. The influence of AK outweighed that of SOC and other nutrients on soil microbial community composition. These findings suggest that T. ramosissima afforestation in the desert‐oasis ecotone has significant impacts on the community composition and α‐diversity of archaea and bacteria, but not fungi, by modifying soil physicochemical properties. This research provides valuable implications for soil management and microbial processes related to the afforestation of salt‐secreting shrubs. [ABSTRACT FROM AUTHOR]

Drylands, comprising semi‐arid, arid, and hyperarid regions, cover approximately 41% of the Earth's land surface and have expanded considerably in recent decades. Even under more optimistic scenarios, such as limiting global temperature rise to 1.5°C by 2100, semi‐arid lands may increase by up to 38%. This study provides an overview of the state‐of‐the‐art regarding changing aridity in arid regions, with a specific focus on its effects on the accumulation and availability of carbon (C), nitrogen (N), and phosphorus (P) in plant–soil systems. Additionally, we summarized the impacts of rising aridity on biodiversity, service provisioning, and feedback effects on climate change across scales. The expansion of arid ecosystems is linked to a decline in C and nutrient stocks, plant community biomass and diversity, thereby diminishing the capacity for recovery and maintaining adequate water‐use efficiency by plants and microbes. Prolonged drought led to a −3.3% reduction in soil organic carbon (SOC) content (based on 148 drought‐manipulation studies), a −8.7% decrease in plant litter input, a −13.0% decline in absolute litter decomposition, and a −5.7% decrease in litter decomposition rate. Moreover, a substantial positive feedback loop with global warming exists, primarily due to increased albedo. The loss of critical ecosystem services, including food production capacity and water resources, poses a severe challenge to the inhabitants of these regions. Increased aridity reduces SOC, nutrient, and water content. Aridity expansion and intensification exacerbate socio‐economic disparities between economically rich and least developed countries, with significant opportunities for improvement through substantial investments in infrastructure and technology. By 2100, half the world's landmass may become dryland, characterized by severe conditions marked by limited C, N, and P resources, water scarcity, and substantial loss of native species biodiversity. These conditions pose formidable challenges for maintaining essential services, impacting human well‐being and raising complex global and regional socio‐political challenges. [ABSTRACT FROM AUTHOR]

The detoxification, metabolism, and excretion of various endogenous and exogenous materials occur mainly in the liver. Liver diseases are a global concern, and classified as chronic hepatitis, cirrhosis, and hepatosis. The development of safe hepatoprotective agents remains an unmet need. Therefore, we investigated the antioxidant effects of methanolic and n-hexane fractions of Zilla spinosa (ZSM and ZSH, respectively) and Hammada elegans (HEM and HEH, respectively) against carbon tetrachloride (CCl4)-induced liver toxicity in rats. Antioxidant activity was studied by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The rats were divided into 11 groups (n=6)–group, 1 (control), group 2 (CCl4 only), group 3 (CCl4+silymarin 10 mg/kg), group 4 (CCl4+HEM 250 mg/kg), group 5 (CC14+HEM 500 mg/kg), group 6 (CCl4+HEH 250 mg/kg), group, 7 (CCl4+HEH 500 mg/kg), group, 8 (CCl4+ZSM 250 mg/kg), group 9 (CCl4+ZSM 500 mg/kg), group 10 (CCl4+ZSH 250 mg/kg), and group 11 (CCl4+ZSH 500 mg/kg). Serum levels of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, gamma glutamyl transferase, and total bilirubin were measured. The extent of hepatic injury was histopathologically assessed. Treatment with ZSM and ZSH at 250 and 500 mg/kg did not significantly affect biochemical results compared with the CCl4 only group. However, treatment with both HEM and HEH at 250 and 500 mg/kg provided significant (p