Ecosystem Phenology: Integrating Traits and Processes Beyond Observable Events.

Phenology-the study of seasonal biological events shaped by climate variability-has long offered critical insights into the impact of climate change on ecosystems. Traditionally, phenological research has focused on discrete and observable events such as budburst, leaf-out, flowering, and migration. Yet ecosystems are not driven by isolated events alone, but by continuous shifts in functional traits and biogeochemical processes.

Phosphorus constrains global photosynthesis more than nitrogen does.

Global vegetation growth is thought to be limited by nitrogen (N) more than by other nutrients. Here we document a stronger phosphorus (P) limitation on global photosynthesis compared with N over the last four decades. On the basis of more than 80,000 field observations of foliar nutrients and a machine learning method, we generated a long-term global dataset of foliar N and P concentrations for the period 1980-2017.

Connecting optical remote sensing of plant photosynthesis with biogenic volatile organic compound emissions.

Plant biogenic volatile organic compounds (BVOCs) play a critical role in atmospheric chemistry by forming ozone and secondary organic aerosols, making them key agents in regulating air quality and influencing climate. However, current models usually rely on limited site-specific data and indirect inputs, introducing significant uncertainties in BVOC predictions. We propose remote sensing of photosynthetic optical signals, such as the carotenoid-sensitive photochemical reflectance index (PRI) and Chl/carotenoid index (CCI) and sun-induced fluorescence (SIF), to help reduce these uncertainties.

Multi-Scale Evidence for Declining Microbial Carbon Fixation Along Forest Succession Gradients.

Although soil carbon accumulates during subtropical forest succession, changes in microbial communities and their carbon fixation capacity remain unclear. Using an integrative approach that combines field experimentation, extensive global metagenomic data, and isotope labelling, we analyzed 84 soil microbiomes from a long-term successional site and 755 global metagenomes to investigate microbial community dynamics and their role in carbon fixation. Based on field data, bacteria, fungi, and protists had synchronous succession with vegetation; however, the relative abundance of carbon fixation genes declined significantly in later successional stages.

Physical protection by soil aggregates drives carbon gains in mangrove restoration: Evidence from coastal aquaculture ponds.

Mangrove wetlands are vital carbon sinks, yet their area has sharply declined due to aquaculture. To evaluate soil carbon stock recovery, we analyzed six pond-to-mangrove restoration sites along China's southeastern coast, assessing changes in carbon components and their drivers. Restoration increased soil water content, salinity, and total nitrogen while reducing pH and bulk density.

Human-Impacted Natural Ecosystems Drive Climate Warming.

Current greenhouse gas budgets do not account for most indirect anthropogenic impacts. In this perspective, we call for attention to greenhouse gas fluxes from human-impacted natural ecosystems and their mitigation measures. The article highlights the increasing greenhouse gas (GHG) emissions from natural ecosystems, including CO, CH, and NO.

Temporal complexity of terrestrial ecosystem functioning and its drivers.

The development of non-linear dynamics theory showed that simple processes can lead to high complexity in the functioning of nature, with ecological studies showing that non-linear dynamics are common across populations of different taxa. However, whether the energy and matter fluxes of entire ecosystems follow non-linear dynamics, and how complex these dynamics are, is still unknown. We investigate the drivers of- and trends in the temporal complexity of ecosystem functioning by calculating the correlation dimension of gross primary production (GPP), ecosystem respiration, and net ecosystem production.

Soil carbon stabilization associated with iron-aluminum complexes and microbial communities in paddy.

Rice paddies play a pivotal role in global carbon cycling, offering significant potential for climate change mitigation and sustainable agriculture. This study investigates the synergistic effects of long-term fertilization, iron-aluminum-soil organic carbon (Fe(Al)-SOC) complexes, and microbial communities on soil organic carbon (SOC) stabilization across major rice-growing regions. Black soils exhibited the highest SOC content (43.

Observed declines in leaf nitrogen explained by photosynthetic acclimation to CO.

Widespread evidence of decreasing leaf nutrients has raised concerns about ecosystem productivity under global change. Interpreting trends in leaf nutrients has important implications for the fate of ecosystem services, particularly the role of forests in mitigating climate change and sustaining quality food sources. Here, we challenge the common interpretation that decreasing leaf nitrogen concentration () is evidence of increasing nutrient limitations on ecosystem primary productivity.

Long-term no-tillage practice with re-used plastic film mulching exacerbates bacterial ecological risks in dryland-based on plastisphere.

Re-used plastic-film (RUPF) mulching has emerged as an innovative and practical agricultural practice to reduce plastic use and the buildup of plastic waste in drylands in China. However, alterations in bacterial community colonisation mechanisms and ecological processes due to plastic contamination in RUPF mulching systems remain unclear. In this study, we examined the distribution and assembly of soil bacterial communities under two RUPF exposure scenarios, weathered plastic film plastisphere (WPS) and soil-buried plastic film plastisphere (BPS), and compared them to no-mulching ambient soil (CK).

Spatiotemporal patterns of methane fluxes across alpine permafrost region on the Tibetan Plateau.

Methane (CH) emissions from thawing permafrost could amplify climate warming. However, long-term trajectory of net CH balance in permafrost regions, particularly high-altitude permafrost regions, remains unknown. Based on literature synthesis and CLM5.

Keys to the global treeline formation: Thermal limit for its position and moisture for the taxon-specific variation.

Alpine treeline is a prominent biogeographic feature worldwide, determined by the physiological limit of tree life form. There are considerable variations in the various dimensions of physiological limit among tree taxa; thus, varied environmental drivers and spatial patterns are expected for different tree taxa at treelines. However, such taxonomic variability of treeline is often overlooked in large-scale studies.

Long-Term Anthropogenic Disturbances Exacerbate Soil Organic Carbon Loss in Hyperarid Desert Ecosystems.

Anthropogenic disturbance is an important driver factor of global change, greatly affects the soil organic carbon (SOC) storage. However, the long-term impacts of anthropogenic disturbance on SOC stability in hyperarid deserts remain poorly understood. Through a 16-year anthropogenic disturbance experiment, we evaluated SOC dynamics in hyper-arid desert ecosystems under five treatments: no-disturbance (CK), spring harvest, autumn harvest, fire, and irrigation (simulating artificial flooding).

Securing the forest carbon sink for the European Union's climate ambition.

The European Union (EU) climate policies rely on a functioning forest carbon sink. Forests cover about 40% of the EU area and have absorbed about 436 Mt of carbon dioxide equivalent per year between 1990 and 2022, which is about 10% of the EU's anthropogenic emissions. However, the ability of forests to act as carbon sinks is rapidly declining owing to increasing natural and anthropogenic pressures, threatening the EU's climate goals and calling for prompt actions.

Lagged precipitation effects on plant production across terrestrial biomes.

Precipitation effects on plant carbon uptake extend beyond immediate timeframes, reflecting temporal lags between rainfall and plant growth. Mechanisms and relative importance of such lagged effects are expected to vary across ecosystems. Here we draw on an extensive collections of productivity proxies from long-term ground measurements, satellite observations and model simulations to show that preceding-year precipitation exerts a comparable influence on plant productivity to current-year precipitation.

Rethinking Organic Carbon Sequestration in Agricultural Soils From the Elemental Stoichiometry Perspective.

Sequestering organic carbon (OC) in soil encompasses complex abiotic and biotic processes that involve vegetation carbon (C) inputs, and following microbial-mediated transformations and mineral-organic associations, which are closely related to environmental constraints in climate change scenarios. Agroecosystems have substantial potential for sequestering OC in soil and thus mitigating climate change, through optimizing management strategies. However, the efficient strategies and underlying mechanisms to fulfill the potential remain largely elusive.

Linking vegetation changes to Arctic methane efflux.

Arctic methane emissions are uncertain, impacting climate models. We propose combining vegetation data with machine learning to improve methane process predictions, offering more reliable insights. This approach can better inform global policies to reduce warming and address climate change effectively.

Synergistic plant-fungal interactions under Phragmites australis - mangrove mixed growth regimes boost particulate organic carbon sequestration in estuarine wetlands.

Estuarine wetlands, as globally critical carbon sink systems, rely heavily on the dynamics of soil particulate organic carbon (POC) to regulate carbon cycling. However, the mechanisms underlying how plant-fungal synergies under mixed plant communities drive POC accumulation remain unclear. This study focuses on the Min River Estuary wetlands, comparing the effects of mangrove wetland, Phragmites australis wetland, and mixed P.

Global evidence for a positive relationship between tree species richness and ecosystem photosynthesis.

Forest biodiversity plays a critical role in sustaining ecosystem functioning and buffering the effects of increased extreme weather events on forests. A global assessment of the relationship between biodiversity and photosynthesis in natural forest ecosystems, however, remains elusive. We used a large dataset of the richness of tree species from a large number of globally distributed forest plots combined with satellite retrievals of sun-induced chlorophyll fluorescence, a novel proxy for photosynthesis, to evaluate the relationship between forest biodiversity and photosynthesis and its biological mechanisms at the global scale.

Shifts in microbial- and plant-derived biomass degradation genes with afforestation promoting carbon accumulation.

Microorganisms decompose plant residue in soil and incorporate it to their biomass, thereby promoting soil carbon (C) accumulation. However, the mechanisms underlying microbial-mediated plant- and microbial-derived C degradation and their response to afforestation remain unclear. Here, soil organic C (SOC), carbohydrate-activated enzymes (CAZymes), and C acquiring enzyme were utilized to investigate microbial-mediated SOC formation after afforestation (3, 7, and 10 years) in an arid region, with uncultivated wasteland serving as the control (0 years).

Mapping previously undetected trees reveals overlooked changes in pan-tropical tree cover.

Detecting tree cover is crucial for sustainable land management and climate mitigation. Here we develop an automatic detection algorithm using high-resolution satellite data (<5 m) to map pan-tropical tree cover (2015-2022), enabling identification and change analysis for previously undetected tree cover (PUTC). Our findings reveal that neglecting PUTC represents 17.

Leaf economic strategies drive global variation in phosphorus stimulation of terrestrial plant production.

Plant biomass and its allocation are fundamental for understanding biospheric matter production. However, the impacts of atmospheric phosphorus (P) deposition on species-specific biomass and its allocation in global terrestrial plants remain unclear. By synthesizing 5548 observations of plant biomass and its allocation related to P addition worldwide, we find that P addition increases plant biomass by an average of 35% globally.

Expanding the Root Economics Space With Root Nitrogen Reallocation.

Harnessing root nitrogen reallocation (RNR) to enhance plant productivity commences with positioning RNR in the root economics space, about which we still know little. We conducted an inclusive synthesis linking RNR to root traits, combined with a 2-year N-labelling field experiment, to position RNR in the root economics space under acidification. RNR was negatively correlated with specific root length (SRL) and mycorrhizal colonisation in the synthesis, suggesting that RNR is a conservative trait.

Nutrient availability drives the ecological linkage between microbial functional diversity and soil organic matter molecular complexity during forest restoration.

Forest restoration facilitates soil organic carbon (SOC) preservation, a process that is fundamentally governed by the molecular complexity of soil organic matter (SOMMC) and its dynamic interaction with microorganisms. Yet, the changes in SOMMC and its ecological linkages with microbial communities, and the mechanisms driving these relationships during forest restoration remain poorly understood. To fill this knowledge gap, we collected O- and A-horizon soil samples across two independent restoration chronosequences in tropical forests and applied thermally-assisted hydrolysis and methylation coupled with gas chromatography and mass spectrometry (THM-GC-MS) for molecular-level SOMMC characterization and high-throughput sequencing for microbial community profiling.

Warming Weakens Soil Nitrogen Stabilization Pathways Driving Proportional Carbon Losses in Subarctic Ecosystems.

Climate warming poses a significant threat to the nitrogen (N) and carbon (C) retention capacities of subarctic ecosystems, with cascading effects on soil nutrient cycling and long-term ecosystem functioning. Here, we investigated the effects sustained soil warming on the temporal retention and stabilization of N in key ecosystem pools in a subarctic grassland performing a N-tracing experiment in different seasons. Our results reveal that warming reduced N retention across key soil pools, with the largest proportional losses occurring in the non-extractable soil fraction, a critical long-term reservoir of organic matter.