Ji Chen

Verified

Ji verified their affiliation via an institutional email.

Learn more

Verified

Ji verified their affiliation via an institutional email.

Learn more

• Professor
• Professor (Full) at Chinese Academy of Sciences

Agricultural and industrial activities have increased atmospheric nitrogen (N) deposition to ecosystems worldwide. N deposition can stimulate plant growth and soil carbon (C) input, enhancing soil C storage. Changes in microbial decomposition could also influence soil C storage, yet this influence has been difficult to discern, partly because of th...

Climate warming affects soil carbon (C) dynamics, with possible serious consequences for soil C stocks and atmospheric CO2 concentrations. However, the mechanisms underlying changes in soil C storage are not well understood, hampering long‐term predictions of climate C‐feedbacks. The activity of the extracellular enzymes ligninase and cellulase can...

Emerging evidence indicates that enzyme‐catalyzed transformation and degradation of soil organic matter at the ecosystem scale is more likely driven by microbial functional gene abundance, rather than short term induction/repression responses. In this paper, we are trying to highlight the potential links between microbial functional gene abundance...

Dissolved organic carbon (DOC) is a critical component of wetland carbon cycling, yet the sources and characteristics of soil-derived dissolved organic matter (DOM) that influence DOC dynamics in inland river wetlands remain poorly understood. This study investigated the spatial variations in DOM sources and composition, and their influence on DOC...

Secondary succession has been demonstrated as one of the effective restoration strategies for enhancing soil organic carbon (SOC) sequestration. Soil aggregates play a crucial role in SOC sequestration by providing habitats for microbes and physically protecting SOC. However, microbial transformations of plant and microbial residues in different ag...

Coastal wetlands have disproportionately high carbon (C) sequestration rates and long-term sustainable C sequestration capacity, contributing to the mitigation of global climate change. Previous studies have mainly focused on the assessment of bulk soil organic C (SOC) in coastal wetlands, neglecting the form in which C is stored, its stability and...

It is widely recognized that increased nitrogen (N) and phosphorus (P) inputs play critical roles in plant carbon (C) inputs and microbial growth and activity, thereby profoundly affecting the composition and dynamics of soil organic C (SOC). However, whether and how plant-and microbial-derived C and their associated SOC fractions respond to the in...

To reveal the effects of long-term warming on soil extracellular enzyme activity, nutrient stoichiometry, and microbial nutrient limitation in the alpine meadow ecosystem on the Tibetan Plateau, this study explores the response mechanisms of microbial nutrient limitation at different soil depths under climate warming. A 13-year simulated warming e...

Perennial crops can be a sustainable alternative to annual crops due to plant traits and management practices that improve productivity and may contribute to soil organic carbon (SOC) sequestration. However, our understanding of the mechanisms behind the potential differences in SOC pools between perennials and annuals is incomplete, particularly i...

Plant litter decomposition plays a vital role in soil carbon (C) cycling and nutrient release, significantly influencing agricultural resource utilization and soil fertility management. Litter quality-defined by its C, nitrogen (N), and phosphorus (P) contents, as well as C:N:P stoichiometry-is a key factor regulating its decomposition. However, th...

Enhanced anthropogenic nitrogen (N) inputs to ecosystems may have substantial impacts on microbially mediated soil organic carbon (SOC) cycling. One way to link species‐rich soil microbial communities with SOC cycling processes is via soil extracellular enzyme activities (EEAs). However, the effects of N addition on EEAs and the associated driving...

Land use/vegetation cover change, reflecting a range of human land use practices , is the most prevalent and immediate influence on alterations in soil quality. The physical structure of soil is crucial for safeguarding soil carbon (C) and nitrogen (N), as it modulates the physical protection mechanisms and the distribution of these elements within...

Subtropical forests are significant contributors to N2O emissions with consequences for climate regulation. Biochar application has emerged as a promising strategy to mitigate soil N2O emissions, yet its effects and the underlying mechanisms under nitrogen (N) deposition in subtropical forests remain poorly understood. A comprehensive 3-year field...

This study examines how nitrogen and phosphorus fertilization influence soil microbial necromass carbon (MNC) content of farmland on the Loess Plateau, central Gansu. Based on an extensive (6 years) experiment, a control (CK, no fertilization) and three treatment groups employing different fertilization methods, namely, nitrogen fertilization (N, 1...

Litter decomposition is a fundamental biogeochemical process for carbon flux and nutrient cycling in terrestrial ecosystems, yet the global variation in decomposition rates and their covariations with climate and substrate are not fully understood. Here, we synthesized a global dataset of 6,733 independent observations across six continents to illu...

Legume-cereal cover crop mixtures offer a promising approach to reduce nitrate leaching and enhancing soil fertility. However, the impacts of these mixtures on N2O emissions during both the cover cropping and post-incorporation phases, as well as the relative contribution of roots and shoots to N 2 O emission, remain uncertain. To address these kno...

Desert riparian ecosystems play a critical role in carbon cycling in arid regions. As a natural barrier between deserts and oases, riparian vegetation reduces the wind’s erosive effect on the soil through its leaves and branches, while its roots stabilize soil nutrients. However, the relative importance of plant- and microbial-derived carbon (C) fo...

Despite the close interactions between carbon (C) and nutrients like nitrogen (N), phosphorus (P), and potassium (K), the consequences of N fertilization alone or in combination with P and K on soil organic matter (SOM) chemical composition remain unclear. Using solid-state 13C nuclear magnetic resonance spectroscopy data from 45 field studies, we...

There are still large uncertainties on the relationships between microbial carbon use efficiency and soil organic carbon across (1) different carbon use efficiency estimation methods, (2) various temporal, spatial and biological scales, and (3) multiple climate change scenarios. These uncertainties call for further efforts to re‐examine the relatio...

Grazing exclusion and land abandonment are commonly adopted to restore degraded ecosystems in semiarid and arid regions worldwide. However, the temporal variation in the soil- versus root-associated microbiome over plant species turnover during secondary succession has rarely been quantified. Using the chronosequence restored from fenced grassland...

Coastal ecosystems are known for their ability to sequester organic carbon (OC), termed “blue carbon”. The molecular composition of dissolved organic matter (DOM) can affect sediment OC content; however, the impact of benthic bioturbation on DOM properties and OC storage stability is not well understood. This study examined the effects of bioturbat...

Nitrate (NO3⁻) leaching from nitrogen (N) fertilized soils is a significant global concern, affecting both the environment and public health. However, substantial uncertainties and variabilities in NO3⁻ leaching factors (LFs) among regions or crops impede accurate assessments of NO3⁻ leaching. Here we synthesize 2500 field observations worldwide an...

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 pa...

This study investigated the geographical patterns and controlling factors of soil extracellular enzyme activities in the alpine grasslands of the Tibetan Plateau, using data from 135 sample sites collected in 2020. The activities of four essential soil extracellular enzymes, namely β-glucosidase (BG), leucine aminopeptidase (LAP), N-Acetyl-β-D-Gluc...

Background Deadwood contains a large reservoir of carbon and nutrients in forest ecosystems, its decomposition has considerable effects on forest soil chemistry and biota. Tree functional group and nutrient inputs both have a significant influence on wood decomposition rates. However, little is known about how these factors interactively influence...

Global warming poses an unprecedented threat to agroecosystems. Although temperature increases are more pronounced during winter than in other seasons, the impact of winter warming on crop biomass carbon has not been elucidated. Here we integrate global observational data with a decade-long field experiment to uncover a significant negative correla...

Soil enzymes play a crucial role in terrestrial ecosystems as they are involved in various key processes that support ecosystem functioning and soil health. While the role of soil enzymes in forest soils under subtropical climates has been documented, the specific patterns and driving factors of soil enzyme activities across various vegetation type...

Soil organic carbon (SOC) represents the largest terrestrial pool of organic carbon and is indispensable for mitigating climate change and sustaining soil fertility. As a major component of stable SOC, microbial-derived carbon (MDC) accounts for approximately half of the total SOC and has repercussions on climate feedback. However, our understandin...

Aim The unregulated use of rare earth elements, such as Europium (Eu), may result in their build-up in soils. Here, we investigated how Eu affects wheat growth, photosynthesis, and redox homeostasis and how Arbuscular mycorrhizal fungi (AMF) may influence these processes. Methods The wheat plants were grown in soil with 1.09 mmol Eu3+/kg and/or AM...

Soil microbial extracellular enzymes play crucial roles in soil carbon and nutrient cycling by catalyzing soil biochemical processes. However, the activity and stoichiometry of enzymes involved in the carbon, nitrogen, and phosphorus cycles in the environment with the highest density of wild giant pandas on the southern slopes of the Qinling Mounta...

Soil organic carbon (SOC) is the largest carbon pool in terrestrial ecosystems and plays a crucial role in mitigating climate change and enhancing soil productivity. Microbial-derived carbon (MDC) is the main component of the persistent SOC pool. However, current formulas used to estimate the proportional contribution of MDC are plagued by uncertai...

National and global food security depend on both supply and demand, yet the vast majority of studies on the impact of climate change on food security have focused somewhat myopically on the supply side. Here, we assess planetary implications of the changing climate for food supply, concurrently considering implications of shifts in dietary preferen...

Atmospheric nitrogen (N) deposition has been substantially reduced due to declines in the reactive N emission in major regions of the world. Nevertheless, the impact of reduced N deposition on soil microbial communities and the mechanisms by which they are regulated remain largely unknown. Here, we examined the effects of N addition and cessation o...

Simple Summary The nitrogen cycling process in alpine wetlands is profoundly affected by precipitation changes. Utilizing high-throughput sequencing analysis of nirS-type functional genes, this study delved into the dynamic response mechanism of nirS-type denitrifiers to precipitation changes in the alpine wetland of Qinghai Lake. The findings reve...

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...

Straw returning has gradually been adopted as an effective approach to address the serious degradation of farmland. However, the carbon/nitrogen (C/N) ratio of rice straw is generally too high for microorganisms to decompose the organic materials and release nutrients, which may minimize the benefits of straw returning to the agricultural productio...

Fungi are key decomposers of deadwood, but the impact of anthropogenic changes in nutrients and temperature on fungal community and its consequences for wood microbial respiration are not well understood. Here, we examined how nitrogen and phosphorus additions (field experiment) and warming (laboratory experiment) together influence fungal composit...

Fungi are key decomposers of deadwood, but the impact of anthropogenic changes in nutrients and temperature on fungal community and its consequences for wood microbial respiration are not well understood. Here, we examined how nitrogen and phosphorus additions (field experiment) and warming (laboratory experiment) together influence fungal composit...

Coastal wetlands are key players in mitigating global climate change by sequestering soil organic matter. Soil organic matter consists of less stable particulate organic matter (POM) and more stable mineral-associated organic matter (MAOM). The distribution and drivers of MAOM and POM in coastal wetlands have received little attention, despite the...

Global soil nitrogen (N) cycling remains poorly understood due to its complex driving mechanisms. Here, we present a comprehensive analysis of global soil δ¹⁵N, a stable isotopic signature indicative of the N input–output balance, using a machine‐learning approach on 10,676 observations from 2670 sites. Our findings reveal prevalent joint effects o...

Land use change (LUC) alters the global carbon (C) stock, but our estimation of the alteration remains uncertain and is a major impediment to predicting the global C cycle. The uncertainty is partly due to the limited number and geographical bias of observations, and limited exploration of its predictors. Here we generated a comprehensive global da...

Enhancing biomass yield simultaneously with soil carbon (C) sequestration is a key aim of climate-smart cropping systems. Perennialization is believed to be a suitable mitigation strategy for climate change with the potential for enhancing soil C stocks. Based on a nine-year field experiment in Denmark, we measured the changes in soil C and nitroge...

Emerging evidence points out that the responses of soil organic carbon (SOC) to nitrogen (N) addition differ along the soil profile, highlighting the importance of synthesizing results from different soil layers. Here, using a global meta‐analysis, we found that N addition significantly enhanced topsoil (0–30 cm) SOC by 3.7% (±1.4%) in forests and...

Although crop conversion from annual to perennial crops has been considered as one path towards climate-smart and resource-efficient agriculture, the effects of this conversion on soil multifunctionality and biomass yields remain unclear. The objective of the study is to enhance soil multifunctionality while exerting a marginal influence on farmer...

Paddy fields serve as significant reservoirs of soil organic carbon (SOC) and their potential for terrestrial carbon (C) sequestration is closely associated with changes in SOC pools. However, there has been a dearth of comprehensive studies quantifying changes in SOC pools following extended periods of rice cultivation across a broad geographical...

A multiple cropping system is beneficial for utilizing natural resources, while increasing the grain production and economic outputs. However, its impact on greenhouse gas emissions is unclear. The objective of this study was to evaluate the influence of rice-based cropping systems on methane (CH4) and nitrous oxide (N2O) emissions, the carbon foot...

Sustainable agriculture should aim to increase grain yield and yield stability while improving soil structure. Despite different straw return practices are widely recommended in agroecosystems targeting sustainable agriculture , few studies have concurrently explored their impact on grain yield, yield stability, soil structural properties, and any...

Although crop conversion from annual to perennial crops has been considered as one path towards climate-smart and resource-efficient agriculture, the effects of this conversion on soil multifunctionality and biomass yields remain unclear. Here, we investigated the effects of one annual and three perennial crops (a grass (Lolium perenne), a legume (...

Aims Afforestation is considered an effective strategy to improve soil carbon (C) and fertility in degraded drylands. However, how specific species identities (e.g., conifers or broadleaves) impact C and nutrient concentrations across deep soil layers remains uncertain. Methods Three most important plantation forests, including plantations of nati...

Compelling evidence has shown that wetland methane emissions are more temperature dependent than carbon dioxide emissions across diverse hydrologic conditions. However, the availability of carbon substrates, which ultimately determines microbial carbon metabolism, has not been adequately accounted for. By combining a global database and a continent...

Coastal wetlands contribute to the mitigation of climate change through the sequestration of “blue carbon”. Microbial necromass, lignin, and glycoproteins (i.e., glomalin-related soil proteins (GRSP)), as important components of soil organic carbon (SOC), are sensitive to environmental change. However, their contributions to blue carbon formation a...

Inorganic fertilizers are widely used to provide crops with significant amounts of nitrogen (N) and phosphorus (P), but can exacerbate soil carbon (C) limitation and acidification. Crop residues with distinct ecological stoichiometry from inorganic fertilizers can help balance soil ecological stoichiometry and thus increase soil organic matter accu...

Microbes inhabiting deep soil layers are known to be different from their counterpart in topsoil yet remain under investigation in terms of their structure, function, and how their diversity is shaped. The microbiome of deep soils (>1 m) is expected to be relatively stable and highly independent from climatic conditions. Much less is known, however...

Grazing exclusion alters grassland soil aggregation, microbiome composition, and biogeochemical processes. However, the long‐term effects of grazing exclusion on the microbial communities and nutrient dynamics within soil aggregates remain unclear. We conducted a 36‐year exclusion experiment to investigate how grazing exclusion affects the soil mic...

Anthropogenic nitrogen (N) loading alters soil ammonia‐oxidizing archaea (AOA) and bacteria (AOB) abundances, likely leading to substantial changes in soil nitrification. However, the factors and mechanisms determining the responses of soil AOA:AOB and nitrification to N loading are still unclear, making it difficult to predict future changes in so...

Supporting food security while maintaining ecosystem sustainability is one of the most important global challenges for humanity. Optimization of cropping systems is expected to promote the ecosystem services of agroecosystems. Yet, how and why cropping system influences the trade‐offs between economic profitability and multiple ecosystem services r...

Whether and how to synchronously regulate stream water nitrogen (N) and phosphorus (P) concentrations and ratios is a major challenge for sustainable aquatic functions. Soil carbon (C):N:P ratios influence soil N and P stocks and biogeochemical processes that elicit subsequent substantial impacts on stream water N and P concentrations and ratios. T...

Enhanced anthropogenic nitrogen (N) inputs to ecosystems may have substantial impacts on soil organic carbon (SOC) cycling. One way to link species-rich soil microorganisms with specific SOC cycling processes is via soil extracellular enzyme activities (EEAs). Here, by presenting a meta-analysis on the response of soil C-degrading EEAs to N additio...

Conservation agriculture is often assumed to reduce soil N 2 O emissions. Yet, studies analyzing the specific effect of conservation agriculture practices on N 2 O emissions give contradictory results. Herein, we synthesized a comprehensive database on the three main conservation agriculture practices (cover crops, diversified crop rotations, and n...

Cover crops may enhance soil organic carbon (SOC) sequestration, but the links among SOC fractions, microbial necromass carbon (C), and SOC sequestration potential in legume and non-legume cover-cropped orchards are unclear. We leveraged data from seven orchards with varying climatic and edaphic properties in China to assess the effects of legume a...

Perennial crops replacing annual crops are drawing global attention because they harbor potential for sustainable biomass production and climate change mitigation through soil carbon sequestration. At present, it remains unclear how long perennial crops can sequester carbon in the soil and how soil carbon stock dynamics are influenced by climate, s...

Globally, reducing carbon emissions and mitigating soil heavy metal pollution pose pressing challenges. We evaluated the effects of lead (Pb) and cadmium (Cd) contamination in the field over 20 years. The five treatment groups featured Pb concentrations of 40 and 250 mg/kg, Cd concentrations of 10 and 60 mg/kg, and a combination of Pb and Cd (60 an...