Microbes drive more carbon dioxide and nitrous oxide emissions from wetland under long-term nitrogen enrichment.

Wetlands are frequently regarded as weak carbon dioxide (CO) sinks, the largest natural sources of methane (CH), and weak sources of nitrous oxide (NO). Anthropogenic activities and climate change-induced nitrogen (N) enrichment may affect wetland carbon (C) and N cycling via soil microbes, consequently modifying the original greenhouse gas (GHG) emissions. However, the effects and mechanisms of the duration and rate of N inputs on wetland GHG emissions remain uncertain and controversial.

Dominant Edaphic Controls on Particulate Organic Carbon in Global Soils.

The current soil carbon paradigm puts particulate organic carbon (POC) as one of the major components of soil organic carbon worldwide, highlighting its pivotal role in carbon mitigation. In this study, we compiled a global dataset of 3418 data points of POC concentration in soils and applied empirical modeling and machine learning algorithms to investigate the spatial variation in POC concentration and its controls. The global POC concentration in topsoil (0-30 cm) is estimated as 3.

Electromechanical coupling modeling and fractional-order control of the seeker stabilization platform.

To address the electromechanical coupling and multi-source disturbance problems of the seeker stabilized platform, this paper constructs an electromechanical coupling model of the seeker stabilized platform based on the Lagrange-Maxwell equation. To mitigate the influence of electromechanical coupling on the control performance of the seeker, a super-twisting controller based on a fractional-order terminal sliding mode surface (FOSTSMC) is proposed. Additionally, to handle various disturbances in the system, this paper introduces a method that combines the extended state observer (ESO) with the proposed controller to enhance the system's stability and anti-disturbance performance.

Insight into Fe-O-Bi electron migration channel in MIL-53(Fe)/BiOI Z-scheme heterojunction for efficient photocatalytic decontamination.

Building a heterojunction is a fascinating option to guarantee sufficient carrier separation and transfer efficiency, but the mechanism of charge migration at the heterojunction interface has not been thoroughly studied. Herein, MIL-53(Fe)/BiOI photocatalyst with a Z-scheme heterojunction structure is constructed, which achieves efficient photocatalytic decontamination under solar light. Driven by the newly-built internal electric field (IEF), the formation of Fe-O-Bi electron migration channel allows for rapid separation and transfer of charge carriers at the heterojunction interface, confirmed by the material characterization and density functional theory (DFT) calculation.

Warming-induced vapor pressure deficit suppression of vegetation growth diminished in northern peatlands.

Recent studies have reported worldwide vegetation suppression in response to increasing atmospheric vapor pressure deficit (VPD). Here, we integrate multisource datasets to show that increasing VPD caused by warming alone does not suppress vegetation growth in northern peatlands. A site-level manipulation experiment and a multiple-site synthesis find a neutral impact of rising VPD on vegetation growth; regional analysis manifests a strong declining gradient of VPD suppression impacts from sparsely distributed peatland to densely distributed peatland.

Isolation and Identification of Biocontrol Bacteria against Root Rot and Their Effects.

Fusarium root rot (FRR) seriously affects the growth and productivity of . Therefore, protecting from FRR has become an important task, especially for increasing production. The purpose of this study was to screen FRR control strains from the rhizosphere soil.

Mapping turnover of dissolved organic carbon in global topsoil.

Dissolved organic carbon (DOC), the labile fraction of organic carbon, is a predominant substrate for microbes. Therefore, the turnover of DOC dominates microbial respiration in soils. We compiled a global dataset (1096 data points) of the turnover rates of DOC in 0-30 cm soil profiles and integrated the data with a machine learning algorithm to develop a global map of DOC turnover rate in global topsoil.

Responses of soil microbes and enzymes to long-term warming incubation in different depths of permafrost peatland soil.

Soil microbes and enzymes mediate soil carbon-climate feedback, and their responses to increasing temperature partly affect soil carbon stability subjected to the effects of climate change. We performed a 50-month incubation experiment to determine the effect of long-term warming on soil microbes and enzymes involved in carbon cycling along permafrost peatland profile (0-150 cm) and investigated their response to water flooding in the active soil layer. Soil bacteria, fungi, and most enzymes were observed to be sensitive to changes in temperature and water in the permafrost peatland.

Environmental stress stimulates microbial activities as indicated by cyclopropane fatty acid enhancement.

Soil microbial responses to environmental stress remain a critical question in microbial ecology. The content of cyclopropane fatty acid (CFA) in cytomembrane has been widely used to evaluate environmental stress on microorganisms. Here, we used CFA to investigate the ecological suitability of microbial communities and found a stimulating impact of CFA on microbial activities during wetland reclamation in Sanjiang Plain, Northeastern China.

Mineral protection controls soil organic carbon stability in permafrost wetlands.

Mineral protection can slow the effect of warming on the mineralization of organic carbon (OC) in permafrost wetlands, which has an important impact on the dynamics of soil OC. However, the response mechanisms of wetland mineral soil to warming in permafrost areas are unclear. In this study, the soil of the southern edge of the Eurasian permafrost area was selected, and bulk and heavy fraction (HF) soil was subjected to indoor warming incubation experiments using physical fractionation.

Soil CO and NO emissions and microbial abundances altered by temperature rise and nitrogen addition in active-layer soils of permafrost peatland.

Changes in soil CO and NO emissions due to climate change and nitrogen input will result in increased levels of atmospheric CO and NO, thereby feeding back into Earth's climate. Understanding the responses of soil carbon and nitrogen emissions mediated by microbe from permafrost peatland to temperature rising is important for modeling the regional carbon and nitrogen balance. This study conducted a laboratory incubation experiment at 15 and 20°C to observe the impact of increasing temperature on soil CO and NO emissions and soil microbial abundances in permafrost peatland.

Semiconducting mineral induced photochemical conversion of PAHs in aquatic environment: Mechanism study and fate prediction.

Semiconducting minerals (such as iron sulfides) are highly abundant in surface water, but their influences on the natural photochemical process of contaminants are still unknown. By simulating the natural water environment under solar irradiation, this work comprehensively investigated the photochemical processes of anthracene (a typical Polycyclic Aromatic Hydrocarbons) in both freshwater and seawater. The results show that the natural pyrite (NP) significantly promotes the degradation of anthracene under solar illumination via 1) NP induced photocatalytic degradation of anthracene, and 2) Fenton reaction due to the NP induced photocatalytic generation of HO.

Ceftriaxone sodium degradation by carbon quantum dots (CQDs)-decorated C-doped α-BiO nanorods.

A novel carbon quantum dots decorated C-doped α-BiO photocatalyst (CBO/CQDs) was synthesized by solvothermal method. The synergistic effect of adsorption and photocatalysis highly improved contaminants removal efficiencies. The ceftriaxone sodium degradation rate constant () of CBO/CQDs was 11.

[Change in nitrogen availability of northern peatlands and its effect on carbon sink function].

Northern peatlands are typical nitrogen-limited ecosystems, which are sensitive to global climate change and human activities. The increases of endogenous available nitrogen caused by climate warming and exogenous nitrogen input caused by human activities changed the nitrogen availability of northern peatlands, and would affect carbon and nitrogen cycling and carbon sink function of peatland. Here, we review the influence factors of carbon accumulation rate and carbon sink function in northern peatlands.

Warming-Induced Labile Carbon Change Soil Organic Carbon Mineralization and Microbial Abundance in a Northern Peatland.

Climate warming affects the carbon cycle of northern peatlands through temperature rises and a changing carbon availability. To clarify the effects of elevated temperature and labile carbon addition on SOC mineralization, as well as their microbial driving mechanisms, topsoil (0-10 cm) and subsoil (10-20 cm) were collected from a peatland in the Great Hing'an Mountains and incubated with or without C-glucose at 10 °C and 15 °C for 42 days. The results showed that 5 °C warming significantly stimulated SOC mineralization along with NH-N and NO-N content increases, as well as a decrease in invertase and urease activities.

Long-term nitrogen addition alters peatland plant community structure and nutrient resorption efficiency.

As an elemental carbon (C) and nitrogen (N) pool in the world, peatlands are very sensitive to environmental changes. Under global warming, the increase in available N affects the dynamic changes of plant community structure and nutrients in a permafrost peatland. This study was based on a long-term in situ N addition experiment that had been conducted for 9 years.

Effect of Nitrogen Addition on Soil Microbial Functional Gene Abundance and Community Diversity in Permafrost Peatland.

Nitrogen is the limiting nutrient for plant growth in peatland ecosystems. Nitrogen addition significantly affects the plant biomass, diversity and community structure in peatlands. However, the response of belowground microbe to nitrogen addition in peatland ecosystems remains largely unknown.

Rising vegetation activity dominates growing water use efficiency in the Asian permafrost region from 1900 to 2100.

Permafrost play an important role in regulating global climate system. We analyzed the gross primary productivity (GPP), net primary productivity (NPP), and evapotranspiration (ET) derived from MODIS and three earth system models participated in the Coupled Model Inter-comparison Project Phase 6 (CMIP6) in the Asian permafrost region. The water use efficiency (WUE) was further computed.

Shifts in soil bacterial and archaeal communities during freeze-thaw cycles in a seasonal frozen marsh, Northeast China.

Diurnal freeze-thaw cycles (FTCs) occur in the spring and autumn in boreal wetlands as soil temperatures rise above freezing during the day and fall below freezing at night. A surge in methane emissions from these systems is frequently documented during spring FTCs, accounting for a large portion of annual emissions. In boreal wetlands, methane is produced as a result of syntrophic microbial processes, mediated by a consortium of fermenting bacteria and methanogenic archaea.

Influence of nitrogen additions on litter decomposition, nutrient dynamics, and enzymatic activity of two plant species in a peatland in Northeast China.

Nitrogen (N) availability affects litter decomposition and nutrient dynamics, especially in N-limited ecosystems. We investigated the response of litter decomposition to N additions in Eriophorum vaginatum and Vaccinium uliginosum peatlands. These two species dominate peatlands in Northeast China.

Effects of permafrost thaw on carbon emissions under aerobic and anaerobic environments in the Great Hing'an Mountains, China.

The carbon (C) pool of permafrost peatland is very important for the global C cycle. Little is known about how permafrost thaw could influence C emissions in the Great Hing'an Mountains of China. Through aerobic and anaerobic incubation experiments, we studied the effects of permafrost thaw on CH4 and CO2 emissions.

Changes in labile organic carbon fractions and soil enzyme activities after marshland reclamation and restoration in the Sanjiang Plain in northeast China.

The extensive reclamation of marshland into cropland has tremendously impacted the ecological environment of the Sanjiang Plain in northeast China. To understand the impacts of marshland reclamation and restoration on soil properties, we investigated the labile organic carbon fractions and the soil enzyme activities in an undisturbed marshland, a cultivated marshland and three marshlands that had been restored for 3, 6 and 12 years. Soil samples collected from the different management systems at a depth of 0-20 cm in July 2009 were analyzed for soil organic carbon (SOC), dissolved organic carbon (DOC), microbial biomass carbon (MBC) and easily degradable organic carbon.

Hydroponic uptake and distribution of nitrobenzene in Phragmites australis: potential for phytoremediation.

Phragmites australis was grown hydroponically in nutrient solutions containing nitrobenzene to examine the potential for treatment of contaminated waters through phytoremediation. The hydroponic solutions and plant tissue were sampled each day during the five day growth period and tested for nitrobenzene. Plant tissue analysis included both rhizome and shoot sections of the plant.