Integrative molecular and physiological insights into the phytotoxic impact of liquid crystal monomer exposure and the protective strategy in plants.

Liquid crystal monomers (LCMs), the integral components in the manufacture of digital displays, have engendered environmental concerns due to extensive utilization and intensive emission. Despite their prevalence and ecotoxicity, the LCM impacts on plant growth and agricultural yield remain inadequately understood. In this study, we investigated the specific response mechanisms of tobacco, a pivotal agricultural crop and model plant, to four representative LCMs (2OdF3B, 5CB, 4PiMeOP, 2BzoCP) through integrative molecular and physiological approaches.

Increased Mineral-Associated Organic Carbon and Persistent Molecules in Allochthonous Blue Carbon Ecosystems.

Coastal wetlands contain very large carbon (C) stocks-termed as blue C-and their management has emerged as a promising nature-based solution for climate adaptation and mitigation. The interactions among sources, pools, and molecular compositions of soil organic C (SOC) within blue C ecosystems (BCEs) remain elusive. Here, we explore these interactions along an 18,000 km long coastal line of salt marshes, mangroves, and seagrasses in China.

Contrasting effects of arsenic on mycorrhizal-mediated silicon and phosphorus uptake by rice.

Silicon (Si) and arbuscular mycorrhizal fungi (AMF) increase plant resistance to various environmental stresses, including heavy metal (and metalloid) toxicity. Although Si and AMF each independently enhance plant tolerance, the nature of their interactions and their combined impacts on nutrient uptake, especially in the context of toxic elements such as arsenic (As), remains to be elucidated. This study investigated AMF-mediated regulation of plant nutrient uptake under As stress using rice, a model Si-accumulating plant.

Iron oxides promote physicochemical stabilization of carbon despite enhancing microbial activity in the rice rhizosphere.

Rice rhizosphere soil is a hotspot of microbial activity and a complex interplay between soil abiotic properties, microbial community and organic carbon (C). The iron (Fe) plaque formation in the rice rhizosphere promotes Fe-bound organic C formation and increases microbial activity. Yet, the overall impact of Fe on C storage via physicochemical stabilization and microbial mineralization of rhizodeposits (rhizo-C) and soil organic C (SOC) in the rice rhizosphere remain unclear.

Nitrogen availability in soil controls uptake of different nitrogen forms by plants.

Nitrogen (N) uptake by plant roots from soil is the largest flux within the terrestrial N cycle. Despite its significance, a comprehensive analysis of plant uptake for inorganic and organic N forms across grasslands is lacking. Here we measured in situ plant uptake of 13 inorganic and organic N forms by dominant species along a 3000 km transect spanning temperate and alpine grasslands.

Soil Organic Carbon Increases With Decreasing Microbial Carbon Use Efficiency During Vegetation Restoration.

Microbial carbon (C) use efficiency (CUE) describes the proportion of organic C used by microorganisms for anabolic processes, which increases with soil organic C (SOC) content on a global scale. However, it is unclear whether a similar relationship exists during natural vegetation restoration in terrestrial ecosystems. Here, we investigated the patterns of CUE along a 160-year vegetation restoration chronosequence (from farmland to climax forest) estimated by stoichiometric modeling; additionally, we examined the relationship between CUE and SOC content and combined these results with a meta-analysis.

Loss of taxonomic and functional diversity and decrease in primary productivity with nitrogen enrichment after a long-term release from grazing in an alpine grassland.

Moderate grazing can sustain high species diversity and productivity. However, nitrogen enrichment often reduces species richness while promoting primary productivity, which contradicts the traditional understanding of the positive effect of plant diversity on productivity. Whether the responses of diversity and productivity to N enrichment on a long-term scale conform to those on short-term scale.

Lithological Controls on Soil Aggregates and Minerals Regulate Microbial Carbon Use Efficiency and Necromass Stability.

Microbial carbon (C) use efficiency (CUE) drives soil C formation, while physical-chemical protection stabilizes subsequent microbial necromass, both shaped by soil aggregates and minerals. Soils inherit many properties from the parent material, yet the influence of lithology and associated soil geochemistry on microbial CUE and necromass stabilization remains unknow. Here, we quantified microbial CUE in well-aggregated bulk soils and crushed aggregates, as well as microbial necromass in bulk soils and the mineral-associated organic matter fraction, originating from carbonate-containing (karst) and carbonate-free (clastic rock, nonkarst) parent materials along a broad climatic gradient.

Response of bacterial and fungal composition in tailings to Mn pollution.

Microorganisms are crucial for natural remediation of heavy metal pollution in mining areas. The regional survey and process analysis of Mn mine microbes is still limited. We investigated microbial species composition in tailings and adjacent soils of seven typical Mn mining areas in wet mid-subtropical China.

Fertilization shapes microbial life strategies, carbon and nitrogen metabolic functions in Camellia oleifera soil.

Mineral and organic fertilizers as well as microbial inoculations are crucial to maintain and to improve soil health and quality, ecosystem functions, and fruit yield in Camellia oleifera plantations. However, how these fertilizers shape the life strategies and functions of microbial communities in soil is unclear. Here, we conducted a one-year field experiment with three types of fertilizers: mineral (NPK), manure (Man), and microbial (MicrF), and analyzed soil properties, bacterial and fungal communities to assess microbial life strategies, functional traits and their determinants.

Physicochemically protected organic carbon release is the rate-limiting step of rhizosphere priming in paddy soils.

Iron oxides affect the stability of soil organic matter (SOM), which in turn affects greenhouse gas emissions in paddy soils. They also regulate the direction and magnitude of the rhizosphere priming effect (RPE) by restricting SOM accessibility and microbial activity. However, the controlling steps and key factors that regulate the RPE magnitude under anoxic conditions are unknown.

Microbial rrn copy number is associated with soil C: N ratio and pH under long-term fertilization.

Soil microbial life-history strategies, as indicated by rRNA operon (rrn) copy numbers, strongly influence agro-ecosystem functioning. Long-term N fertilization causes strong and lasting changes in soil properties, yet its impact on microbial strategies remains largely unexplored. Using long-term field experiments across three agro-ecosystems, we consistently found that N fertilization strongly decreased soil C: N ratio and pH, further increasing the community-level rrn copy number, including both average rrn copy number and total 16S rRNA copy number.

Trade-off between soil enzyme activities and hotspots area depends on long-term fertilization: In situ field zymography.

Mineral fertilizers and livestock manure have been found to impact soil enzyme activities and distributions, but their trade-off and subsequent effects on soil functioning related to nutrient cycling are rarely evaluated. Here, we investigated the long-term effects of manure and mineral fertilization on the spatial distribution of enzyme activities related to carbon, nitrogen, and phosphorus cycling under field-grown maize. We found that the legacy of mineral fertilizers increased the rhizosphere extension for β-glucosidase and N-acetylglucosaminidase by 16-170 %, and the hotspots area by 37-151 %, compared to manure.

Positive soil priming effects are the rule at a global scale.

Priming effects of soil organic matter decomposition are critical to determine carbon budget and turnover in soil. Yet, the overall direction and intensity of soil priming remains under debate. A second-order meta-analysis was performed with 9296-paired observations from 363 primary studies to determine the intensity and general direction of priming effects depending on the compound type, nutrient availability, and ecosystem type.

Effects of environmental changes on soil respiration in arid, cold, temperate, and tropical zones.

Soil respiration (R) is projected to be substantially affected by climate change, impacting the storage, equilibrium, and movement of terrestrial carbon (C). However, uncertainties surrounding the responses of R to climate change and soil nitrogen (N) enrichment are linked to mechanisms specific to diverse climate zones. A comprehensive meta-analysis was conducted to address this, evaluating the global effects of warming, increased precipitation, and N enrichment on R across various climate zones and ecosystems.

Wildfire effects on mercury fate in soils of North-Western Siberia.

Arctic soils store 49 Gg mercury (Hg) - an extremely toxic heavy metal, whereas soil Hg can be released to the atmosphere by wildfires. For the first time we investigated the effects of wildfires on the fate of soil Hg in North-Western (NW) Siberia based on GIS maps of areas burned during the last 38 years and a field paired comparison of unburned and burned areas in tundra (mosses, lichens, some grasses, and shrubs) and forest-tundra (multi-layered canopy of larch trees, shrubs, mosses, and lichens). These field surveys were deepened by soil controlled burning to assess the Hg losses from organic horizon and mineral soil.

Limiting Resources Define the Global Pattern of Soil Microbial Carbon Use Efficiency.

Microbial carbon (C) use efficiency (CUE) delineates the proportion of organic C used by microorganisms for anabolism and ultimately influences the amount of C sequestered in soils. However, the key factors controlling CUE remain enigmatic, leading to considerable uncertainty in understanding soil C retention and predicting its responses to global change factors. Here, we investigate the global patterns of CUE estimate by stoichiometric modeling in surface soils of natural ecosystems, and examine its associations with temperature, precipitation, plant-derived C and soil nutrient availability.

Assembly processes and co-occurrence of bacterial communities in tree rhizosphere under Pb-Zn contamination.

Rhizosphere bacteria are critical for supporting plant performance in stressful environments. Understanding the assembly and co-occurrence of rhizosphere bacterial communities contributes significantly to both plant growth and heavy metal accumulation. In this study, Ligustrum lucidum and Melia azedarach were planted in soils with simulated varying levels of Pb-Zn contamination.