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Our research assesses the effects of four forest species, namely, Swietenia macrophylla King, Swietenia mahagoni (L.) Jack., Pinus occidentalis Swartz, and Pinus caribaea Morelet var. Caribaea, on the soil and litter organic carbon (C) stocks, C dioxide equivalent balance (BCO2 Eq.) diurnal, and periodic dynamics beneath these species. Reforestation projects in the study region cover 1200, 543, 770, and 1152 hectares, respectively, with these four species being the most relevant in reforestation projects within the country. To determine the BCO2 Eq. per unit area, we compared the greenhouse gas (GHG) fluxes of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) expressed as CO2 Eq. units with the organic C stocks found in the mineral soil to a depth of 30 cm and in the forest litter. In four measurement periods over 18 months, we conducted field measurements in sixteen stands, four per species. Our results indicate that S. mahagoni emitted the lowest CO2 Eq., while S. macrophylla released the highest amount into the atmosphere. At the end of the 18 months, BCO2 Eq. from S. macrophylla soils was 299.70 metric tons ha−1 year−1, while for P. occidentalis, P. caribaea, and S. mahagoni, the corresponding quantities were 103.64, 146.41, and 72.34, respectively. All species showed a general upward pattern in soil respiration from September 2020 to March 2022. The average CO2 Eq. flux rates to the atmosphere were approximately 65.4, 51.1, and 75.9 percent higher in S. macrophylla soils compared to the respective rates of P. occidentalis, P. caribaea, and S. mahagoni. [ABSTRACT FROM AUTHOR]

The availability of compostable plastic bags has increased greatly in the past few years, as it is perceived that this type of bags will be degraded after disposal. However, there are some knowledge gaps regarding the potential effects on the soil ecosystems. We assessed the rate of degradation of samples of four different types of commercial compostable bags in vermicomposting systems with the earthworm species Eisenia andrei. We also evaluated the biological response of E. andrei (survival and reproduction) to microplastics (MPs) from fragments of the plastic bags (Lepidium sativum L.) exposed to micronized plastic (L. sativum seedling emergence was not significantly affected; however, earthworm reproduction was affected, suggesting that although compostable, some of the formulations may potentially be toxic to soil fauna.

The availability of compostable plastic bags has increased greatly in the past few years, as it is perceived that this type of bags will be degraded after disposal. However, there are some knowledge gaps regarding the potential effects on the soil ecosystems. We assessed the rate of degradation of samples of four different types of commercial compostable bags in vermicomposting systems with the earthworm species Eisenia andrei. We also evaluated the biological response of E. andrei (survival and reproduction) to microplastics (MPs) from fragments of the plastic bags (<2000 µm) and assessed seedling emergence in common garden cress (Lepidium sativum L.) exposed to micronized plastic (<250 µm) and the respective leachate, following OECD and ISO guidelines, respectively. The rate of degradation differed significantly depending on the type of plastic rather than the substrate in the vermicomposting system. This finding suggests that the degradation process is more dependent on the microbial community colonizing the different plastic types than on earthworm activity. Regarding the biological response of the soil system, L. sativum seedling emergence was not significantly affected; however, earthworm reproduction was affected, suggesting that although compostable, some of the formulations may potentially be toxic to soil fauna. [ABSTRACT FROM AUTHOR]

Variation in herbivore pressure has often been predicted from patterns in plant traits considered as antiherbivore defences. Here, we tested whether spatial variation in field insect herbivory is associated with the variation in plant quality by conducting a meta‐analysis of 223 correlation coefficients between herbivory levels and the expression of selected plant traits. We found no overall correlation between herbivory and either concentrations of plant secondary metabolites or values of physical leaf traits. This result was due to both the large number of low correlations and the opposing directions of high correlations in individual studies. Field herbivory demonstrated a significant association only with nitrogen: herbivore pressure increased with an increase in nitrogen concentration in plant tissues. Thus, our meta‐analysis does not support either theoretical prediction, i.e., that plants possess high antiherbivore defences in localities with high herbivore pressure or that herbivory is low in localities where plant defences are high. We conclude that information about putative plant defences is insufficient to predict plant losses to insects in field conditions and that the only bottom‐up factor shaping spatial variation in insect herbivory is plant nutritive value. Our findings stress the need to improve a theory linking plant putative defences and herbivory. [ABSTRACT FROM AUTHOR]

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 database of 5,980 observations from 790 articles. The number of sites evaluated is at least seven times larger than in previous meta‐analyses. Our constrained estimates of different LUC's effects on soil organic C (SOC) and their variations across global climates reveal underestimation/overestimation in previous estimates. Converting forests and grasslands to croplands reduced SOC by 24.5% ± 1.53% (−11.03 ± 1.06 Mg ha−1) and 22.7% ± 1.22% (−8.09 ± 0.67 Mg ha−1), while 28.0% ± 1.56% (4.46 ± 0.42 Mg ha−1) and 33.5% ± 1.68% (5.8 ± 0.38 Mg ha−1) increases, respectively, were obtained in the reverse processes. Converting forests to grasslands decreased SOC by 2.1% ± 1.22% (−1.13 ± 0.44 Mg ha−1), while the reverse process increased SOC by 18.6% ± 1.73% (3.31 ± 0.51 Mg ha−1). Modeled relative importance of 10 drivers of LUC's impact on SOC revealed that higher initial SOC (iSOC) does not solely determine SOC loss in SOC‐negative LUC scenarios as previously proposed. Across four decades, reconverting croplands to forests and grasslands recovered only 49.5% (6.1 ± 0.51 Mg ha−1) and 75.3% (7.0 ± 0.38 Mg ha−1) of the iSOC, respectively, indicating the need for protecting C‐rich ecosystems. Our global data set advances information on LUC's effect on SOC and can be valuable to constrain Earth system models to reliably estimate global SOC stocks and plan climate change mitigation strategies. Plain Language Summary: Land use change (LUC) could increase or decrease the global soil organic carbon (SOC) stock and affect carbon cycling and climate change, but estimating its effect size is the most uncertain aspect of the global carbon cycle. Available estimates vary among studies, most of which often use few observations that do not cover most global regions. To provide more accurate estimates of different LUC types' effects on SOC, we compiled a comprehensive database that contains 5,980 observations across all global regions; and revealed that previous studies have underestimated/overestimated these effects. We modeled the predictors of SOC change and found that previous conclusions that higher initial SOC is the main reason for higher organic carbon loss under negative LUC scenarios were inexact. We show that land use practices aimed at restoring SOC could only recover part of the amount lost during similar time frames; hence, it is important to protect carbon‐rich ecosystems. Our study provides robust estimates of LUC's effect on SOC and provides data sets that can reliably assess and model the global carbon cycle and plan strategies for controlling global climate change. Key Points: Comprehensive global database advances robust estimates of land use change's (LUCs) effect on soil organic carbon (SOC) vital for Earth system modelingHigher initial SOC does not solely control rapid SOC loss in carbon‐negative LUC as often proposedDespite SOC buildup in the past four decades, the amount lost cannot be regained by restoration during similar time frames [ABSTRACT FROM AUTHOR]

Micro(nano)plastics (MNPs) are pervasive pollutants posing significant environmental and health risks. Selecting appropriate sentinel species to assess MNPs in terrestrial and aquatic environments involves considering factors such as species behavior, habitat, exposure pathways, and the feasibility of sampling. For these reasons, it was imperative to launch a virtual special issue (VSI) in Ecological Indicators. This editorial summarizes the contributions submitted to the VSI, which invited research on bioindicators of MNPs, including sampling protocols, monitoring strategies, and analytical methods, to advance our understanding and management of plastic pollution. The VSI received a total of 12 contributions from four countries, with a significant majority originating from Italy. To present the contributions, we have organized the sections into original articles and reviews. The original articles are further divided into sections on the occurrence of MNPs in biotic and abiotic compartments, the selection of bioindicators, and the effects and risk assessment of MPs. The reviews are categorized based on their focus on aquatic and terrestrial ecosystems. Future ecotoxicology studies should select bioindicators based on exposure to MNPs, conservation status, ecological roles, and human consumption.

Through their rooting profiles and water demands, plants affect the distribution of water in the soil profile. Simultaneously, soil water content controls plant development and interactions within and between plant communities. These plant-soil water feedbacks might vary across plant communities with different rooting depths and species composition. In semiarid environments, understanding these differences will be essential to predict how ecosystems will respond to drought, which may become more frequent and severe with climate change. In this study, we tested how plant-soil water feedbacks responded to drought in two contrasting ecosystem types—grassland and shrubland—in the coastal foothills of southern California. During years 5–8 of an ongoing precipitation manipulation experiment, we measured changes in plant communities and soil moisture up to 2 m depth. We observed different water use patterns in grassland and shrubland communities with distinct plant functional types and water use strategies. Drought treatment did not affect perennial, deep-rooted shrubs because they could access deep soil water pools. However, mid-rooted shrubs were sensitive to drought and experienced decreased productivity and die-off. As a result, water content actually increased with drought at soil depths from 50–150 cm. In grassland, biomass production by annual species, including annual grasses and forbs, declined with drought, resulting in lower water uptake from the surface soil layer. An opportunistic “live fast, die young“ life strategy allowed these species to recover quickly once water availability increased. Our results show how drought interacts with plant community composition to affect the soil water balance of semiarid ecosystems, information that could be integrated into global scale models.

Despite numerous studies assessing the effects of microplastics (MPs) on soils and plants and their potential implications for human consumption and agriculture, there remains a lack of exploration on the role of vegetated ecosystems as natural filters of MPs pollution. The MPs stemming from anthropogenic continental activities may undergo retention within these ecosystems, preventing their dispersion into aquatic environments. However, questions are raised about their potential impact on plant health and soil quality. This review aims to address these gaps by examining studies analyzing the role of vegetated ecosystems in MPs retention, the sources and effects of these contaminants on soils, and their absorption/translocation into plants analyzing their direct effects on plant physiology and growth. Finally, future perspectives and knowledge gaps in these crucial research areas were explored.The main findings demonstrate that plants effectively play a crucial role in retaining MPs, with studies mainly focused on vegetated wetlands with halophytes, and that MPs could affect various soil properties, including bulk density, water retention, and microbiota, inducing oxidative stress on plants and disturbing their growth. However, research gaps persist, such as quantifying MPs in natural settings and investigating the complex relationship between MPs, plants, and ecosystems. Experiments often employed high concentrations of MPs, potentially deviating from natural environmental levels and thus requiring assessment of whether observed concentrations can elicit comparable effects. Additionally, the predominant focus on primary MPs in experiments overlooked other types derived from degradation of larger plastic items, warranting attention and inclusion in research efforts.In conclusion, vegetated ecosystems can naturally filter MPs from land-based activities before they reach aquatic environments. Nevertheless, these particles exhibit significant impacts on soil properties and plant growth, posing an emerging threat to terrestrial ecosystems that requires further study.

Abstract 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 database of 5,980 observations from 790 articles. The number of sites evaluated is at least seven times larger than in previous meta‐analyses. Our constrained estimates of different LUC's effects on soil organic C (SOC) and their variations across global climates reveal underestimation/overestimation in previous estimates. Converting forests and grasslands to croplands reduced SOC by 24.5% ± 1.53% (−11.03 ± 1.06 Mg ha−1) and 22.7% ± 1.22% (−8.09 ± 0.67 Mg ha−1), while 28.0% ± 1.56% (4.46 ± 0.42 Mg ha−1) and 33.5% ± 1.68% (5.8 ± 0.38 Mg ha−1) increases, respectively, were obtained in the reverse processes. Converting forests to grasslands decreased SOC by 2.1% ± 1.22% (−1.13 ± 0.44 Mg ha−1), while the reverse process increased SOC by 18.6% ± 1.73% (3.31 ± 0.51 Mg ha−1). Modeled relative importance of 10 drivers of LUC's impact on SOC revealed that higher initial SOC (iSOC) does not solely determine SOC loss in SOC‐negative LUC scenarios as previously proposed. Across four decades, reconverting croplands to forests and grasslands recovered only 49.5% (6.1 ± 0.51 Mg ha−1) and 75.3% (7.0 ± 0.38 Mg ha−1) of the iSOC, respectively, indicating the need for protecting C‐rich ecosystems. Our global data set advances information on LUC's effect on SOC and can be valuable to constrain Earth system models to reliably estimate global SOC stocks and plan climate change mitigation strategies.

Our research assesses the effects of four forest species, namely, Swietenia macrophylla King, Swietenia mahagoni (L.) Jack., Pinus occidentalis Swartz, and Pinus caribaea Morelet var. Caribaea, on the soil and litter organic carbon (C) stocks, C dioxide equivalent balance (BCO2 Eq.) diurnal, and periodic dynamics beneath these species. Reforestation projects in the study region cover 1200, 543, 770, and 1152 hectares, respectively, with these four species being the most relevant in reforestation projects within the country. To determine the BCO2 Eq. per unit area, we compared the greenhouse gas (GHG) fluxes of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) expressed as CO2 Eq. units with the organic C stocks found in the mineral soil to a depth of 30 cm and in the forest litter. In four measurement periods over 18 months, we conducted field measurements in sixteen stands, four per species. Our results indicate that S. mahagoni emitted the lowest CO2 Eq., while S. macrophylla released the highest amount into the atmosphere. At the end of the 18 months, BCO2 Eq. from S. macrophylla soils was 299.70 metric tons ha−1 year−1, while for P. occidentalis, P. caribaea, and S. mahagoni, the corresponding quantities were 103.64, 146.41, and 72.34, respectively. All species showed a general upward pattern in soil respiration from September 2020 to March 2022. The average CO2 Eq. flux rates to the atmosphere were approximately 65.4, 51.1, and 75.9 percent higher in S. macrophylla soils compared to the respective rates of P. occidentalis, P. caribaea, and S. mahagoni.

Through their rooting profiles and water demands, plants affect the distribution of water in the soil profile. Simultaneously, soil water content controls plant development and interactions within and between plant communities. These plant-soil water feedbacks might vary across plant communities with different rooting depths and species composition. In semiarid environments, understanding these differences will be essential to predict how ecosystems will respond to drought, which may become more frequent and severe with climate change. In this study, we tested how plant-soil water feedbacks responded to drought in two contrasting ecosystem types—grassland and shrubland—in the coastal foothills of southern California. During years 5–8 of an ongoing precipitation manipulation experiment, we measured changes in plant communities and soil moisture up to 2 m depth. We observed different water use patterns in grassland and shrubland communities with distinct plant functional types and water use strategies. Drought treatment did not affect perennial, deep-rooted shrubs because they could access deep soil water pools. However, mid-rooted shrubs were sensitive to drought and experienced decreased productivity and die-off. As a result, water content actually increased with drought at soil depths from 50–150 cm. In grassland, biomass production by annual species, including annual grasses and forbs, declined with drought, resulting in lower water uptake from the surface soil layer. An opportunistic "live fast, die young" life strategy allowed these species to recover quickly once water availability increased. Our results show how drought interacts with plant community composition to affect the soil water balance of semiarid ecosystems, information that could be integrated into global scale models. [ABSTRACT FROM AUTHOR]

Summary: Potassium (K+) is the most abundant inorganic cation in plant cells, playing a critical role in various plant functions. However, the impacts of K on natural terrestrial ecosystems have been less studied compared with nitrogen (N) and phosphorus (P).Here, we present a global meta‐analysis aimed at quantifying the response of aboveground production to K addition. This analysis is based on 144 field K fertilization experiments. We also investigate the influences of climate, soil properties, ecosystem types, and fertilizer regimes on the responses of aboveground production.We find that: K addition significantly increases aboveground production by 12.3% (95% CI: 7.4–17.5%), suggesting a widespread occurrence of K limitation across terrestrial ecosystems; K limitation is more prominent in regions with humid climates, acidic soils, or weathered soils; the effect size of K addition varies among climate zones/regions, and is influenced by multiple factors; and previous N : K and K : P thresholds utilized to detect K limitation in wetlands cannot be applied to other biomes.Our findings emphasize the role of K in limiting terrestrial productivity, which should be integrated into future terrestrial ecosystems models. [ABSTRACT FROM AUTHOR]

Terrestrial ecosystems are under the enormous pressure of land use management regimes through human disturbances, resulting in the disruption of biogeochemical cycles and associated ecosystem services. Nitrogen (N) in soil ecosystems is of vital importance for primary productivity, hence estimating the extent of these human interventions on N-cycling processes becomes imperative from economic and environmental perspectives. This work investigated the impacts of variable anthropogenic activities on N cycling in three different terrestrial ecosystems (arable, grassland, and forest) in three regions of lower Himalaya, Pakistan. Potential nitrification (PNA) and denitrification (DEA) enzyme activities, relative distribution of inorganic N species (NH4, NO3), and the role of inherent edaphic factors were assessed. Results revealed high nitrification potentials and increased nitrous oxide (N2O) emissions in the incubated soil microcosms, in the order as arable > grassland > forest ecosystems. Notably, higher rates of both studied processes (~ 30–50%) and elevated soil mineral nitrogen pool were observed in arable ecosystems. Forest soils, assumed as pristine ecosystems relying mainly on natural N fixation, produced (de)nitrification rates relatively lower than grasslands, followed by arable soils which were moderately disturbed through long-term fertilization and intensive land-use regimes. Linear regression modeling revealed that the inorganic N species (particularly NO3), and inherent edaphic factors were the key determinants of high (de)nitrification rates, hence warn of accelerated N losses in these ecosystems. The study highlights that elevated PNA and DEA being proxies for the altered N cycling in the studied terrestrial ecosystems are of great ecological relevance in view of predicted N2O budget in the lower Himalaya. [ABSTRACT FROM AUTHOR]

Silicon fertilisers are widely utilised to achieve higher productivity in global terrestrial ecosystems, but their impact on the carbon cycle remains unclear. In this study, we used a meta-analysis approach to quantify the response of carbon pools and fluxes in terrestrial ecosystems worldwide to the application of silicon fertiliser while also investigating the factors influencing this response. The findings indicated that silicon fertiliser application led to significant increases in various carbon components: plant aboveground carbon increased by 22.9%, plant belowground carbon increased by 17.3%, litter carbon increased by 8.3%, and the SOC content increased by 8.6%. Furthermore, the net photosynthetic rate of plants was significantly enhanced by 28.1% through the application of silicon fertiliser, along with a notable increase of 36.9% in the net primary productivity of ecosystems, which exhibited a strong correlation with alterations in ecosystem carbon pools. A considerable reduction of 29.6% in soil CH4 emissions was observed, whereas the influence of silicon fertiliser on the litter decomposition rate and net soil CO2 emissions was not statistically significant. Moreover, fertilisation (such as vegetation and soil types), climatic conditions, and silicon fertiliser application techniques have been found to affect the responses of carbon pools and fluxes to silicon fertiliser application. Finally, a potential mechanism by which silicon fertilisation can affect plant growth, litterfall, soil organic carbon stability, and soil carbon emissions directly and indirectly by changing the available silicon and soil pH is proposed to explain the positive effects of silicon fertiliser application on terrestrial ecosystem carbon pools. This effect may change owing to the influence of fertilisation technology, fertilisation, climate, and other factors.

Abstract Objectives Soil fauna plays a crucial role in contributing to litter breakdown, accelerating the decomposition rate and enhancing the biogeochemical cycle in terrestrial ecosystems. Comprehending the specific fauna role of functional species in litter decomposition is challenging due to their vast numbers and diversity. Climate and litter quality are widely acknowledged as dominant drives of litter decomposition across large spatial scales. However, the pattern of climate and litter quality modulates the effect of soil fauna on litter decomposition remains largely unexplored. To address this gap, we conducted an extensive analysis using data from 81 studies to investigate how climate and litter traits affects soil fauna in the decomposition. Data description The paper describes fauna body size, climate zones (tropical, subtropical and temperate), ecosystem types (forest, grassland, wetland and farmland), soil types (sand, loam and clay), decomposed duration ( 360 days), litter initial traits, average annual temperature and precipitation. The litter traits encompass various parameters such as concentrations of carbon, nitrogen, phosphorus, potassium, lignin, cellulose, total phenol, condensed tannin, hydrolysable tannin and other nutrient traits. These comprehensive datasets provide valuable insights into the role of soil fauna on the decomposition at global scale. Furthermore, the data will give researchers keys to assess how climate, litter quality and soil fauna interact to determine decomposition rates.

The fraction of absorbed photosynthetically active radiation (FPAR) is a key biophysiological parameter of terrestrial ecosystems. However, due to a lack of data with adequate spatial resolution and in long enough time series, there have been limitations in exploring the spatiotemporal changes of vegetation and response to climate change. In this study, a 1 km spatial resolution and 8-day period length dataset (FPARANN) was developed covering the years 1980 to 2018 and evaluated on spatiotemporal change consistency by validating with Gross Primary Production (GPP) observations from the Chinese Flux Observation and Research Network (ChinaFLUX), and comparison with other FPAR products. FPARANN provided a comparable performance in capturing seasonal change observed through GPP, according to the coefficient of determination (R2): 0.50, 0.51, 0.70 and 0.74 averaged for all sites, forest sites, grassland sites and cropland flux sites, respectively. The new data had more spatial similarity to the MODIS FPAR product (FPARMCD15A2) with a greater R2 (0.77) and a lower RMSE (0.12) than other products. With a newly developed dataset, combined with FPARANN (1980–2003) and FPARMCD15A2 (2004–2018), an overall increasing trend in FPAR was found for over 81% of the vegetated area of China from 1980 to 2018. FPAR increased more rapidly for over 83.7% of the area in the 2010s, and at a slower pace for over 62.1% of the area in the early 2000s, which was attributed to a decadal shifting of climate change. This study implies the new dataset is useful in quantifying vegetation changes and would be an important data source for future study of the carbon cycle, soil erosion, or evapotranspiration, with great application potential. [ABSTRACT FROM AUTHOR]

There is an unprecedented array of new satellite technologies with capabilities for advancing our understanding of ecological processes and the changing composition of the Earth's biosphere at scales from local plots to the whole planet. We identified 48 instruments and 13 platforms with multiple instruments that are of broad interest to the environmental sciences that either collected data in the 2000s, were recently launched, or are planned for launch in this decade. We have restricted our review to instruments that primarily observe terrestrial landscapes or coastal margins and are available under free and open data policies. We focused on imagers that passively measure wavelengths in the reflected solar and emitted thermal spectrum. The suite of instruments we describe measure land surface characteristics, including land cover, but provide a more detailed monitoring of ecosystems, plant communities, and even some species then possible from historic sensors. The newer instruments have potential to greatly improve our understanding of ecosystem functional relationships among plant traits like leaf mass area (LMA), total nitrogen content, and leaf area index (LAI). They provide new information on physiological processes related to photosynthesis, transpiration and respiration, and stress detection, including capabilities to measure key plant and soil biophysical properties. These include canopy and soil temperature and emissivity, chlorophyll fluorescence, and biogeochemical contents like photosynthetic pigments (e.g., chlorophylls, carotenoids, and phycobiliproteins from cyanobacteria), water, cellulose, lignin, and nitrogen in foliar proteins. These data will enable us to quantify and characterize various soil properties such as iron content, several types of soil clays, organic matter, and other components. Most of these satellites are in low Earth orbit (LEO), but we include a few in geostationary orbit (GEO) because of their potential to measure plant physiological traits over diurnal periods, improving estimates of water and carbon budgets. We also include a few spaceborne active LiDAR and radar imagers designed for quantifying surface topography, changes in surface structure, and 3-dimensional canopy properties such as height, area, vertical profiles, and gap structure. We provide a description of each instrument and tables to summarize their characteristics. Lastly, we suggest instrument synergies that are likely to yield improved results when data are combined.

Objectives: Soil fauna plays a crucial role in contributing to litter breakdown, accelerating the decomposition rate and enhancing the biogeochemical cycle in terrestrial ecosystems. Comprehending the specific fauna role of functional species in litter decomposition is challenging due to their vast numbers and diversity. Climate and litter quality are widely acknowledged as dominant drives of litter decomposition across large spatial scales. However, the pattern of climate and litter quality modulates the effect of soil fauna on litter decomposition remains largely unexplored. To address this gap, we conducted an extensive analysis using data from 81 studies to investigate how climate and litter traits affects soil fauna in the decomposition. Data description: The paper describes fauna body size, climate zones (tropical, subtropical and temperate), ecosystem types (forest, grassland, wetland and farmland), soil types (sand, loam and clay), decomposed duration (< 180, 180–360, > 360 days), litter initial traits, average annual temperature and precipitation. The litter traits encompass various parameters such as concentrations of carbon, nitrogen, phosphorus, potassium, lignin, cellulose, total phenol, condensed tannin, hydrolysable tannin and other nutrient traits. These comprehensive datasets provide valuable insights into the role of soil fauna on the decomposition at global scale. Furthermore, the data will give researchers keys to assess how climate, litter quality and soil fauna interact to determine decomposition rates. [ABSTRACT FROM AUTHOR]

Existing quantitative syntheses on how biodiversity responds to anthropogenic habitat change appear to sometimes mix different biodiversity metrics in drawing inferences. This "mixing metrics" practice, if prevalent, would considerably bias our understanding of biodiversity responses and render uninterpretable conclusions. However, the prevalence of this practice remains unknown, and the bias it potentially renders has not been empirically assessed. We fill this gap by conducting a systematic literature assessment of existing syntheses on biodiversity responses to habitat change, along with an analysis of a global database specifically on forest restoration. We found that the "mixing metrics" practice was used in almost a quarter of existing syntheses across a wide range of ecosystem and habitat change types. This practice predictably altered the quantitative, and frequently even the qualitative, inferences on biodiversity responses to forest restoration, in ways contingent on the composition of metrics mixed. We call on future syntheses to be cognizant of the difference in metric meaning and behaviors, and to avoid mixing different metrics in studying biodiversity responses to habitat change. [ABSTRACT FROM AUTHOR]

The production and disposal of plastics have become significant concerns for the sustainability of the planet. During the past 75 years, around 80% of plastic waste has either ended up in landfills or been released into the environment. Plastic debris released into the environment breaks down into smaller particles through fragmentation, weathering, and other disintegration processes, generating microplastics (plastic particles ≤ 5 mm in size). Although marine and aquatic ecosystems have been the primary focus of microplastic pollution research, a growing body of evidence suggests that terrestrial ecosystems are equally at risk. Microplastic contamination has been reported in various terrestrial environments from several sources such as plastics mulch, pharmaceuticals and cosmetics, tire abrasions (tire wear particles), textiles industries (microfibers), sewage sludge, and plastic dumping. Recent studies suggest that the soil has become a significant sink for pollutants released into terrestrial ecosystems and is often contaminated with a mixture of organic and inorganic pollutants. This has gradually caused adverse impacts on soil health and fertility by affecting soil pH, porosity, water-holding capacity, and soil microbial enzymatic activities. Microplastics can interact with the co-existing pollutants of the environments by adsorbing the contaminants onto their surfaces through various intermolecular forces, including electrostatic, hydrophobic, non-covalent, partition effects, van der Waals forces, and microporous filling mechanisms. This subsequently delays the degradation process of existing contaminants, thereby affecting the soil and various ecological activities of the ecosystem. Thus, the present article aims to elucidate the deleterious impact of microplastics and their interactions with other pollutants in the terrestrial ecosystem. This review also addresses the impact of microplastics in disrupting the soil sustainability of the planet. [ABSTRACT FROM AUTHOR]

Carrion production is one of the most crucial yet neglected and understudied processes in food webs and ecosystems. In this study, we performed a large-scale estimation of the maximum potential production and spatial distribution of ungulate carrion biomass from five major sources in peninsular Spain, both anthropogenic (livestock, big game hunting, roadkills) and natural (predation, natural mortality). Using standardized ungulate carrion biomass (kg/year/100km2) estimates, we evaluated the relationship between ungulate carrion production and two ecosystem-level factors: global human modification (GHM) and primary productivity (NDVI). We found that anthropogenic carrion sources supplied about 60 times more ungulate carrion biomass than natural sources (mean = 90,172 vs. 1533 kg/year/100km2, respectively). Within anthropogenic carrion sources, livestock was by far the major carrion provider (91.1% of the annual production), followed by big game hunting (7.86%) and roadkills (0.05%). Within natural carrion sources, predation of ungulates provided more carrion (0.81%) than natural mortality (0.13%). Likewise, we found that the spatial distribution of carrion differed among carrion sources, with anthropogenic carrion being more aggregated in space than natural carrion. Our models showed that GHM was positively related to carrion production from livestock and roadkills, and that wild ungulate carrion supplied by natural sources and big game hunting was more frequently generated in more productive areas (higher NDVI). These findings indicate a disconnection between the main ungulate carrion source (livestock) and primary productivity. Ongoing socio-economic changes in developed countries (for example increase of intensive livestock husbandry and rewilding processes) could lead to additional alteration of carrion production processes, with potential negative impacts at the community and ecosystem levels. Overall, we highlight that carrion biomass quantification should be considered a crucial tool in evaluating ecosystem health and delineating efficient ecosystem management guidelines in the Anthropocene. [ABSTRACT FROM AUTHOR]

Forests sequester ∼25% of anthropogenic carbon (C) emissions annually and are of increasing interest for their potential as Nature‐based Climate Solutions (NbCS). Emergent from the need to assess terrestrial ecosystem health and quantify C storage and fluxes, several gridded products documenting terrestrial C and changes in C stocks over time have been developed. However, researchers have not yet systematically compared C distributions across products, or developed a clear path forward for investigating and leveraging this cross‐product uncertainty in estimates of terrestrial C. Alaniz et al. (2022, https://doi.org/10.1029/2021EF002560) synthesize multiple published products to constrain the distribution of forest C stocks and fluxes globally. Building off of their results, we comment on opportunities for advancing both basic science and NbCS policy recommendations through systematic product cross‐comparisons and targeting of areas with differing levels of uncertainties in the terrestrial C sink. Plain Language Summary: Forests absorb and store a large amount of the carbon from the CO2 emitted by humans. These forests also provide the potential for storing more human emitted CO2 that helps delay climate change through targeted forest management. However, for both natural sciences and management, careful documentation of the amount of carbon in forests and how it is changing is necessary. Over time the number of ways to measure and evaluate this carbon has increased. The synthesis in Alaniz et al. (2022, https://doi.org/10.1029/2021EF002560) of these numerous efforts provides an integrated view of carbon in forests and how it is changing. We propose expanding these observational synthesis efforts, leveraging uncertainty to help direct both basic scientific research and the potential for managing ecosystems to delay climate change. Key Points: Monitoring forest carbon is important both for basic science and climate change mitigationCross‐dataset comparisons are increasingly important with increasing data availability to characterize uncertaintyUncertainty in terrestrial carbon stocks and fluxes can be used to gain better process understanding and make policy recommendations [ABSTRACT FROM AUTHOR]

Intensive human exploitation of the Antarctic fur seal (Arctocephalus gazella) in its primary population centre on sub-Antarctic South Georgia, as well as on other sub-Antarctic islands and parts of the South Shetland Islands, in the eighteenth and nineteenth centuries rapidly brought populations to the brink of extinction. The species has now recovered throughout its original distribution. Non-breeding and yearling seals, almost entirely males, from the South Georgia population now disperse in the summer months far more widely and in higher numbers than there is evidence for taking place in the pre-exploitation era. Large numbers now haul out in coastal terrestrial habitats in the South Orkney Islands and also along the north-east and west coast of the Antarctic Peninsula to at least Marguerite Bay. In these previously less- or non-visited areas, the seals cause levels of damage likely never to have been experienced previously to fragile terrestrial habitats through trampling and over-fertilisation, as well as eutrophication of sensitive freshwater ecosystems. This increased area of summer impact is likely to have further synergies with aspects of regional climate change, including reduction in extent and duration of sea ice permitting seals access farther south, and changes in krill abundance and distribution. The extent and conservation value of terrestrial habitats and biodiversity now threatened by fur seal distribution expansion, and the multiple anthropogenic factors acting in synergy both historically and to the present day, present a new and as yet unaddressed challenge to the agencies charged with ensuring the protection and conservation of Antarctica's unique ecosystems. [ABSTRACT FROM AUTHOR]

Abstract Existing quantitative syntheses on how biodiversity responds to anthropogenic habitat change appear to sometimes mix different biodiversity metrics in drawing inferences. This “mixing metrics” practice, if prevalent, would considerably bias our understanding of biodiversity responses and render uninterpretable conclusions. However, the prevalence of this practice remains unknown, and the bias it potentially renders has not been empirically assessed. We fill this gap by conducting a systematic literature assessment of existing syntheses on biodiversity responses to habitat change, along with an analysis of a global database specifically on forest restoration. We found that the “mixing metrics” practice was used in almost a quarter of existing syntheses across a wide range of ecosystem and habitat change types. This practice predictably altered the quantitative, and frequently even the qualitative, inferences on biodiversity responses to forest restoration, in ways contingent on the composition of metrics mixed. We call on future syntheses to be cognizant of the difference in metric meaning and behaviors, and to avoid mixing different metrics in studying biodiversity responses to habitat change.

The issue of plastic pollution is recognised as a pervasive and ubiquitous problem which can pose a threat to ecosystems worldwide and potentially affect human health. In this perspective, we selected the latest research that identifies potential impacts beyond individual species to draw attention on wider biogeochemical cycles and the most fundamental biological processes we all depend on, namely, breathing, feeding and carrying offspring. We highlight the need for uniform research methods, giving examples of protocols and indicator species that should be evaluated by the research community for their potential wide adoption. We stress the need for systemic changes and our role as scientific community to demand changes proportionate to the severity and implications of our findings. We further explore the push and pull mechanisms between researchers and policymakers in relation to the global environmental challenges such as plastic pollution. Finally, we recommend a path of action inspired by the global action taken to address the ozone layer depletion by banning chlorofluorocarbons (CFC).

IntroductionGlobal climate change, increase in human activities, and prominence of ecological issues have led to uneven quantitative and spatial distributions of carbon emission and sequestration of terrestrial ecosystems. Such uneven distributions can lead to more negative impacts on the natural environment and human living conditions.MethodsTherefore, based on the carbon neutralization policy, we conducted geographically weighted regression (GWR) modeling in this study using panel data from 352 Chinese prefectural administrative districts in 2000, 2005, 2010, and 2017 to analyze and determine the impact factors and their spatial distribution for carbon emission and sequestration of terrestrial ecosystems.ResultsOur results showed that total population (TP), per capita gross domestic product (GDP) (PCG), proportion of secondary industry output (PSIO), scale of urban built-up area (SUB), green space proportion in city areas (GSP), normalized difference vegetation index (NDVI), and temperature (TEM) are factors driving carbon sequestration and carbon emission. The spatial distribution of these driving factors in mainland China is: (1) TP showed a negative correlation to carbon emission in most areas, while it exhibited a positive correlation to carbon sequestration in the southern, southwestern, and western parts of northwest China; however, in all other areas, TP showed a negative correlation with carbon sequestration; (2) PCG was positively correlated to carbon emission in most areas of China and to carbon sequestration in southwest, south, central, and northeast China; however, PCG demonstrated a negative correlation to carbon sequestration in the remaining areas; (3) PSIO and SUB presented a positive correlation to carbon emission and a negative correlation to carbon sequestration in most areas; (3) In contrast, GSP showed a negative correlation to carbon emission and a positive correlation to carbon sequestration in most areas; (5)NDVI showed a negative correlation to carbon emission and carbon sequestration in most areas toward the east of the “Heihe-Tengchong Line”; NDVI was positively correlated to both carbon emission and sequestration toward the west of this line; (6)TEM was positively correlated to carbon emission and sequestration in most parts of China.DiscussionBased on these results, we further divided the Chinese cities into 6 groups: (1) Groups 1, 2, 3, and 6 are areas where carbon emission and sequestration are governed by both socioeconomic and natural ecological factors. The major driving factors of carbon emission and carbon sequestration in group 1 are PSIO, GSP, and NDVI; the driving factors of group 2 are SUB and NDVI. Meanwhile, carbon emission and sequestration in group 3 are governed by PCG, GSP, and NDVI; for group 6, carbon emission and sequestration are controlled by PCG, SUB, GSP, and NDVI; (2) Group 4 represents areas where carbon emission and sequestration are majorly impacted by PCG and SUB, thereby rendering socioeconomic factors as the major driving forces. Group 5 represents areas where carbon emission and sequestration are sensitive to the natural environment, with GSP and NDVI being the driving factors. Considering the uneven distribution of carbon sequestration and emission and the diverse driving factors in different areas of China, we provided guidance for future environmental policies aimed at reducing the uneven distribution of carbon sequestration and emission in different areas to achieve carbon neutralization.

The Northern Hemisphere mid-latitudes, with large human populations and terrestrial carbon sinks, have a high demand for and dependence on water resources. Despite the growing interest in vegetation responses to drought under climate change in this region, our understanding of changes in the relationship between vegetation growth and water availability (referred to as Rvw) remains limited. Here, we aim to explore the Rvw and its drivers in the Northern Hemisphere mid-latitudes between 1982 and 2015. We used the satellite-derived normalized difference vegetation index (NDVI) and the fine-resolution Palmer drought severity index (PDSI) as proxies for vegetation growth and water availability, respectively. The trend analysis results showed that changes in NDVI and PDSI were asynchronous over the past three decades. Moreover, we analyzed the spatiotemporal patterns of the correlation coefficient between NDVI and PDSI. The results indicated that the Rvw was getting closer in more areas over the period, but there were differences across ecosystems. Specifically, most croplands and grasslands were primarily constrained by water deficit, which was getting stronger; however, most forests were primarily constrained by water surplus, which was getting weaker. Furthermore, our random forest regression models indicated that the dominant driver of changes in the NDVI-PDSI correlation was atmospheric carbon dioxide (CO _2 ) in more than 45% of grid cells. In addition, the partial correlation analysis results demonstrated that elevated CO _2 concentrations not only boosted vegetation growth through the fertilizer effect but also indirectly enhanced water availability by improving water use efficiency. Overall, this study highlights the important role of atmospheric CO _2 in mediating the Rvw under climate change, implying a potential link between vegetation greening and drought risk.

The relevance. Pollution of ecosystems with heavy metals and arsenic is a significant anthropogenic factor that adversely affects humans and biota. In the Sverdlovsk region, where mining and processing of mineral raw materials is carried out, high levels of pollutant emissions from stationary sources, including heavy metals, are noted. The region is also characterized by multicomponent contamination of territories with artificial radionuclides. Since 1964, the Beloyarsk NPP has been in operation in the Sverdlovsk region. The long-term operation of industrial enterprises and radiation hazardous facilities increases the technogenic load on the ecosystems of the Urals. The main aim of the research is to assess the content of heavy metals and arsenic in the soils of terrestrial ecosystems in the vicinity of industrial enterprises and the Beloyarsk NPP based on environmental monitoring. Objects. In 2013 and 2019 the soils of natural (meadow) and agricultural (arable land, grassland) ecosystems of the 30-km zone of influence of the Beloyarsk NPP were studied. The content of 17 elements related to I (Pb, Zn, Cd, As, Hg), II (Mo, Cu, Ni, Co, Cr, Sb), III (Sr, Mn, V, W, Ba) hazard classes was studied in the soil cover, as well as iron. Methods. The assessment of the total content of heavy metals and arsenic in the soil was carried out in the testing laboratory of agroecology of the RIRAE (accreditation certificate RA.RU.513078). To prepare soil samples for measurements, we used the methods of «cold vapor» and «wet ashing» with a MARS-5 microwave system (CEM, USA). The elements in the samples were determined by atomic absorption and plasma emission methods of analysis. For measurements, we used an axial atomic emission (optical) spectrometer with sample atomization in inductively coupled plasma (ICP–OES) Liberty II (Varian, Australia–USA) and a KVANT spectrometer Zeta-1 with the GRG-3. Results. It is shown that for 2013−2019 the ratio of elements in the soil cover of terrestrial ecosystems in the vicinity of the Beloyarsk NPP was quite stable. According to the decrease in the total content in the soil, heavy metals and arsenic in 2019 were arranged in the following order: Fe (average − 16700 mg/kg)>Mn (879)>Ba (134)>Zn (51)>Ni (35)≥Cr ( 32)≥V (30)≥Sr (28)>Cu (21)>Pb (12,4)≥Co (11,9)>W (6,7)>Sb (2,4)>As (1,7)≥Mo (1,5)>Cd (0,2)>Hg (0,01 mg/kg). According to the total accumulation of elements in the soil, terrestrial ecosystems are in the ratio: arable land (18,7 g/kg of soil)>meadows (14,9 g/kg)>virgin land (12,6 g/kg). Such a distinction is due to differences in the content of iron in the soil, the contribution of which to the regional background is 90…95 %. A weak correlation between the content of elements in the soil and the distance from the Beloyarsk NPP (–0,44...0,29 in 2013 and –0,29...0,38 in 2019) showed the absence of significant emissions of toxicants into the environment from the nuclear power plant both as a result of its many years of work, and after the start of operation of the BN-800 reactor. Among the I hazard class pollutants accumulated in the soil, zinc dominates (contribution 76…78 %), lead is in second place (18...21 %). In II hazard class, the main soil pollutants are nickel (45…34 %) and chromium (28…30 %). In III hazard class is dominated by manganese (68...81 %) and barium (14...27 %). It is shown that in 25…63 % of soil samples in the vicinity of the Beloyarsk NPP, the gross nickel content does not correspond to the approximate permissible concentrations established in SanPiN 1.2.3685−21. In addition, in all control plots of meadow ecosystems, the maximum permissible concentration for the content of antimony was exceeded. In 2019, in 4…25 % of soil samples of arable land and meadows, a discrepancy was noted with maximum permissible concentration for manganese, and in 4…11 % of soil samples of arable land, the maximum permissible concentration for arsenic was exceeded. The levels of accumulation in the soil of a number of heavy metals also exceed the regional background of the Sverdlovsk region: for nickel in 25...63 % of soil samples of natural and agricultural ecosystems, for manganese in 10...50 % of soil samples of arable land and meadows. The greatest amount of elements (average 42 %) is accumulated in the 0−5 cm soil layer. The maximum accumulation in the upper soil horizon was noted for cadmium (62 %), arsenic (49 %), and lead (48 %), and the minimum for antimony (29 %) and manganese (28 %). According to the total stock of toxicants in the 0−5 cm soil layer, they are arranged in a row: Cd>As>Pb>Zn>Cu>Mo>Hg>Sr>Ni>Cr>V>W>Co>Ba>Sb>Mn. In deeper horizons (5−10, 10−15 and 15−20 cm) of soil the elements are distributed evenly. Compared to other technogenically-polluted regions of Russia, the results of monitoring the content of heavy metals and arsenic in the soil of the Beloyarsk NPP area show a stable ecological situation. When planning further monitoring studies, it is necessary to pay attention to the behavior of arsenic, nickel, antimony, manganese, cadmium and lead in the soil. The increased content of these toxicants in the soil can lead to their accumulation in agricultural and natural food products.

Abstract Forests sequester ∼25% of anthropogenic carbon (C) emissions annually and are of increasing interest for their potential as Nature‐based Climate Solutions (NbCS). Emergent from the need to assess terrestrial ecosystem health and quantify C storage and fluxes, several gridded products documenting terrestrial C and changes in C stocks over time have been developed. However, researchers have not yet systematically compared C distributions across products, or developed a clear path forward for investigating and leveraging this cross‐product uncertainty in estimates of terrestrial C. Alaniz et al. (2022, https://doi.org/10.1029/2021EF002560) synthesize multiple published products to constrain the distribution of forest C stocks and fluxes globally. Building off of their results, we comment on opportunities for advancing both basic science and NbCS policy recommendations through systematic product cross‐comparisons and targeting of areas with differing levels of uncertainties in the terrestrial C sink.

Biological nitrogen fixation represents the largest natural flux of new nitrogen (N) into terrestrial ecosystems, providing a critical N source to support net primary productivity of both natural and agricultural systems. When they are common, symbiotic associations between plants and bacteria can add more than 100 kg N ha−1 y−1 to ecosystems. Yet, these associations are uncommon in many terrestrial ecosystems. In most cases, N inputs derive from more cryptic sources, including mutualistic and/or free-living microorganisms in soil, plant litter, decomposing roots and wood, lichens, insects, and mosses, among others. Unfortunately, large gaps remain in the understanding of cryptic N fixation. We conducted a literature review to explore rates, patterns, and controls of cryptic N fixation in both unmanaged and agricultural ecosystems. Our analysis indicates that, as is common with N fixation, rates are highly variable across most cryptic niches, with N inputs in any particular cryptic niche ranging from near zero to more than 20 kg ha−1 y−1. Such large variation underscores the need for more comprehensive measurements of N fixation by organisms not in symbiotic relationships with vascular plants in terrestrial ecosystems, as well as identifying the factors that govern cryptic N fixation rates. We highlight several challenges, opportunities, and priorities in this important research area, and we propose a conceptual model that posits an interacting hierarchy of biophysical and biogeochemical controls over N fixation that should generate valuable new hypotheses and research. [ABSTRACT FROM AUTHOR]

Urbanization, agricultural production, natural resource extractions and climate change are global drivers of terrestrial ecosystem degradation and decline in ecosystem health. Assessing vegetation structures provides valuable direct and indirect information on biodiversity and ecosystem health, since plant communities govern terrestrial ecosystem functions and overall biodiversity.A growing body of literature supports the hypothesis that acoustic profiling and characterization of soundscapes may reveal natural patterns and ecosystem responses to environmental disturbances. Although assessments of ecosystem soundscapes are a promising tool for ecological monitoring, the influence of vegetation structure on acoustic indices remains largely unaddressed. An effective non‐invasive approach to monitoring ecosystem health includes use of active acoustic transducers, which convert mechanical/acoustic energy into electrical energy and visa‐versa.This article reviews and discusses possible applications (and also constraints) of active acoustic transducers in monitoring and assessments of terrestrial ecosystem health. Specifically, this article includes a brief introduction to the basic principles of sound and types of active acoustic transducers. Moreover, we provide reviews of common uses of active acoustic transducers in assessing plant structures and plant functional traits.We emphasize that active acoustic transducers can be used to analyse plant characteristics in a remote, scalable, non‐invasive and cost‐effective manner to characterize overall terrestrial ecosystem health. Suggestions and recommendations for future research and management directions that may facilitate applications of acoustic transducers to natural terrestrial landscapes are provided. [ABSTRACT FROM AUTHOR]

Microplastic (MP) pollution, a global environmental problem, has been recently studied in marine and freshwater environments. However, our understanding of MP effect on terrestrial ecosystems, especially carbon (C) and nitrogen (N) turnover remains poor. This review summarizes the sources and distribution characteristics of MPs in terrestrial ecosystems and explores their effects on soil properties, plant growth, C and N turnover. Once entering the terrestrial ecosystem, MPs could involve in sequestrating carbon and nitrogen by changing soil properties (e.g., pH, soil aggregate stability, and soil porosity). MPs could exert direct influences on plants or on soil physical environment and microbial metabolic environment to indirectly affect plant growth, thus altering the quantity and quality of soil C and N inputs by shifts in plant litter and roots. The changes of the dominant bacteria phyla, related functional genes, and enzymes caused by MP pollution could affect C and N cycles. Additionally, the MP effect varies with its properties (e.g., types, shapes, elemental composition, functional groups, released additives). Future researches should unify the standard system of MP separation, detection, and reveal the ecological effects of MPs, especially their impacts on terrestrial carbon and nitrogen cycles in the context of climate changes. [ABSTRACT FROM AUTHOR]

Micro(nano)plastics (MNPs) are pervasive pollutants posing significant environmental and health risks. Selecting appropriate sentinel species to assess MNPs in terrestrial and aquatic environments involves considering factors such as species behavior, habitat, exposure pathways, and the feasibility of sampling. For these reasons, it was imperative to launch a virtual special issue (VSI) in Ecological Indicators. This editorial summarizes the contributions submitted to the VSI, which invited research on bioindicators of MNPs, including sampling protocols, monitoring strategies, and analytical methods, to advance our understanding and management of plastic pollution. The VSI received a total of 12 contributions from four countries, with a significant majority originating from Italy. To present the contributions, we have organized the sections into original articles and reviews. The original articles are further divided into sections on the occurrence of MNPs in biotic and abiotic compartments, the selection of bioindicators, and the effects and risk assessment of MPs. The reviews are categorized based on their focus on aquatic and terrestrial ecosystems. Future ecotoxicology studies should select bioindicators based on exposure to MNPs, conservation status, ecological roles, and human consumption. [ABSTRACT FROM AUTHOR]

Exploring the contribution of protected areas to carbon sequestration services is meaningful to enhance the role of protected areas in climate change mitigation globally. However, less attention has been paid to the contribution of different types of protected areas to carbon sequestration services as well as their changes, which is not conducive to provide more effective solutions in the context of future climate change. Here, we identified the status and changes of carbon sequestration in different types of terrestrial protected areas in China and calculated the amount of carbon sequestration in different ecosystems in terrestrial protected areas and in different climatic zones. Our results indicated that carbon sequestration of China’s terrestrial protected areas had shown a significant increasing trend over the past 40 years (1980–2020) (R2 = 0.862, p

Decadally cycling soil carbon (dSOC) is the main component of the terrestrial soil carbon (C) pool. The response of dSOC to warming largely determines the feedback between climate warming and the C cycle. However, there is a lack of investigations about the effect of warming on the relative change in turnover rate (RCT) of dSOC and annually cycling SOC (aSOC) in dissolved organic carbon (DOC), microbial biomass carbon (MBC) and CO2. We clarified this issue by incubating two C3-C4 vegetation switch soils (23 years switch, HA soil and 55 years switch, GG soil) at 20°C and 30°C in the recently improved continuous airflow CO2 trapping system for 1 year. Warming increased the contribution of dSOC (C3-C) by 21℅ (soil HA) and 8℅ (soil GG) in MBC, and 38℅ (soil HA) and 15℅ (soil GG) in CO2, while only 2%–3℅ increase in DOC at the final stage of the incubation. Furthermore, warming increased the RCT in MBC and CO2 by 5.3- and 4.1-fold, respectively, but had no significant influence on the RCT in DOC, indicating that soil microbes may be an important engine to accelerate dSOC-derived CO2 emission in a warming world.

Rapid Arctic environmental change affects the entire Earth system as thawing permafrost ecosystems release greenhouse gases to the atmosphere. Understanding how much permafrost carbon will be released, over what time frame, and what the relative emissions of carbon dioxide and methane will be is key for understanding the impact on global climate. In addition, the response of vegetation in a warming climate has the potential to offset at least some of the accelerating feedback to the climate from permafrost carbon. Temperature, organic carbon, and ground ice are key regulators for determining the impact of permafrost ecosystems on the global carbon cycle. Together, these encompass services of permafrost relevant to global society as well as to the people living in the region and help to determine the landscape-level response of this region to a changing climate. [ABSTRACT FROM AUTHOR]

Simple Summary: The innovative concept of environmental DNA has found its foot in aquatic ecosystems but remains an unexplored area of research concerning terrestrial ecosystems. When making management choices, it is important to understand the rate of eDNA degradation, the persistence of DNA in terrestrial habitats, and the variables affecting eDNA detectability for a target species. Therefore an attempt has been made to provide comprehensive information regarding the exertion of eDNA in terrestrial ecosystems from 2012 to 2022. The information provided will assist ecologists, researchers and decision-makers in developing a holistic understanding of environmental DNA and its applicability as a biodiversity monitoring contrivance. The dearth of cardinal data on species presence, dispersion, abundance, and habitat prerequisites, besides the threats impeded by escalating human pressure has enormously affected biodiversity conservation. The innovative concept of eDNA, has been introduced as a way of overcoming many of the difficulties of rigorous conventional investigations, and is hence becoming a prominent and novel method for assessing biodiversity. Recently the demand for eDNA in ecology and conservation has expanded exceedingly, despite the lack of coordinated development in appreciation of its strengths and limitations. Therefore it is pertinent and indispensable to evaluate the extent and significance of eDNA-based investigations in terrestrial habitats and to classify and recognize the critical considerations that need to be accounted before using such an approach. Presented here is a brief review to summarize the prospects and constraints of utilizing eDNA in terrestrial ecosystems, which has not been explored and exploited in greater depth and detail in such ecosystems. Given these obstacles, we focused primarily on compiling the most current research findings from journals accessible in eDNA analysis that discuss terrestrial ecosystems (2012–2022). In the current evaluation, we also review advancements and limitations related to the eDNA technique. [ABSTRACT FROM AUTHOR]

Summary: Plant litter decomposition is a key process for carbon (C) turnover in terrestrial ecosystems. Sunlight has been shown to cause and accelerate C release in semiarid ecosystems, yet the dose–response relationships for these effects have not been evaluated.We conducted a two‐phase experiment where plant litter of three species was subjected to a broad range of cumulative solar radiation (CSR) exposures under field conditions. We then evaluated the relationships between CSR exposure and abiotic mass loss, litter quality and the subsequent biotic decomposition and microbial activity in litter.Dose–response relationships demonstrated that CSR exposure was modestly correlated with abiotic mass loss but highly significantly correlated with lignin degradation, saccharification, microbial activity and biotic decay of plant litter across all species. Moreover, a comparison of these dose–response relationships suggested that small reductions in litter lignin due to exposure to sunlight may have large consequences for biotic decay.These results provide strong support for a model that postulates a critical role for lignin photodegradation in the mechanism of photofacilitation and demonstrate that, under natural field conditions, biotic degradation of plant litter is linearly related with the dose of solar radiation received by the material before coming into contact with decomposer microorganisms. [ABSTRACT FROM AUTHOR]

The premise that the intensity of biotic interactions decreases with increasing latitudes and elevations is broadly accepted; however, whether these geographical patterns can be explained within a common theoretical framework remains unclear. Our goal was to identify the general pattern of elevational changes in trophic interactions and to explore the sources of variation among the outcomes of individual studies. Meta‐analysis of 226 effect sizes calculated from 134 publications demonstrated a significant but interaction‐specific decrease in the intensity of herbivory, carnivory and parasitism with increasing elevation. Nevertheless, this decrease was not significant at high latitudes and for interactions involving endothermic organisms, for herbivore outbreaks or for herbivores living within plant tissues. Herbivory similarly declined with increases in latitude and elevation, whereas carnivory showed a fivefold stronger decrease with elevation than with latitude and parasitism increased with latitude but decreased with elevation. Thus, although these gradients share a general pattern and several sources of variation in trophic interaction intensity, we discovered important dissimilarities, indicating that elevational and latitudinal changes in these interactions are partly driven by different factors. We conclude that the scope of the latitudinal biotic interaction hypothesis cannot be extended to incorporate elevational gradients. [ABSTRACT FROM AUTHOR]

Aim: Soil fauna has a wide range of ecosystem functions. Anthropogenic atmospheric nitrogen (N) deposition affects the structure and function of soil fauna by changing the microenvironment and resources. Given that soil faunal responses can vary considerably among taxonomic groups, N deposition rate, and ecosystems, however, there is little consensus. We aimed to evaluate the effects of N deposition on different soil faunal taxa across different terrestrial ecosystems. Location: Global. Time period: 1970–2021. Major taxa studied: Soil fauna. Methods: We conducted a meta‐analysis that yielded 264 observations from 43 publications. We evaluated the responses to N addition of soil faunal abundance for three different taxa (nematodes, mites, collembolans) in three ecosystem types (cropland, forest, and grassland). Results: Our results showed an overall negative effect of N addition on soil fauna. However, the effect varied among soil faunal taxa. Specifically, N addition had no significant effects on the abundance of collembolans and mites in any ecosystem. On the other hand, N addition significantly reduced the abundance of all nematode trophic groups except bacterivores. The overall reduction of soil fauna is likely driven by the nematode response. The negative effects of N addition on nematode abundance were contingent on the N addition rate, N addition form, and ecosystem type. N addition decreased nematode abundance at N addition rates of more than 100 kg/ha/year. Inorganic N addition negatively affected nematode abundance. Finally, N addition had a greater adverse effect on nematodes in cropland and grassland compared to forest ecosystems. Main conclusions: Our results demonstrate the overall negative effects of N addition on nematode abundance. Excessive N addition should be avoided in cropland and grassland management. Further, we suggest the application of organic fertilizer instead of inorganic fertilizer to minimize the N‐induced negative effects on soil nematodes. [ABSTRACT FROM AUTHOR]

Abstract Background Countries have long been making efforts by reducing greenhouse-gas emissions to mitigate climate change. In the agreements of the United Nations Framework Convention on Climate Change, involved countries have committed to reduction targets. However, carbon (C) sink and its involving processes by natural ecosystems remain difficult to quantify. Methods Using a transient traceability framework, we estimated country-level land C sink and its causing components by 2050 simulated by 12 Earth System Models involved in the Coupled Model Intercomparison Project Phase 5 (CMIP5) under RCP8.5. Results The top 20 countries with highest C sink have the potential to sequester 62 Pg C in total, among which, Russia, Canada, USA, China, and Brazil sequester the most. This C sink consists of four components: production-driven change, turnover-driven change, change in instantaneous C storage potential, and interaction between production-driven change and turnover-driven change. The four components account for 49.5%, 28.1%, 14.5%, and 7.9% of the land C sink, respectively. Conclusion The model-based estimates highlight that land C sink potentially offsets a substantial proportion of greenhouse-gas emissions, especially for countries where net primary production (NPP) likely increases substantially and inherent residence time elongates.

The fraction of absorbed photosynthetically active radiation (FPAR) is a key biophysiological parameter of terrestrial ecosystems. However, due to a lack of data with adequate spatial resolution and in long enough time series, there have been limitations in exploring the spatiotemporal changes of vegetation and response to climate change. In this study, a 1 km spatial resolution and 8-day period length dataset (FPARANN) was developed covering the years 1980 to 2018 and evaluated on spatiotemporal change consistency by validating with Gross Primary Production (GPP) observations from the Chinese Flux Observation and Research Network (ChinaFLUX), and comparison with other FPAR products. FPARANN provided a comparable performance in capturing seasonal change observed through GPP, according to the coefficient of determination (R2): 0.50, 0.51, 0.70 and 0.74 averaged for all sites, forest sites, grassland sites and cropland flux sites, respectively. The new data had more spatial similarity to the MODIS FPAR product (FPARMCD15A2) with a greater R2 (0.77) and a lower RMSE (0.12) than other products. With a newly developed dataset, combined with FPARANN (1980–2003) and FPARMCD15A2 (2004–2018), an overall increasing trend in FPAR was found for over 81% of the vegetated area of China from 1980 to 2018. FPAR increased more rapidly for over 83.7% of the area in the 2010s, and at a slower pace for over 62.1% of the area in the early 2000s, which was attributed to a decadal shifting of climate change. This study implies the new dataset is useful in quantifying vegetation changes and would be an important data source for future study of the carbon cycle, soil erosion, or evapotranspiration, with great application potential.

The production and disposal of plastics have become significant concerns for the sustainability of the planet. During the past 75 years, around 80% of plastic waste has either ended up in landfills or been released into the environment. Plastic debris released into the environment breaks down into smaller particles through fragmentation, weathering, and other disintegration processes, generating microplastics (plastic particles ≤ 5 mm in size). Although marine and aquatic ecosystems have been the primary focus of microplastic pollution research, a growing body of evidence suggests that terrestrial ecosystems are equally at risk. Microplastic contamination has been reported in various terrestrial environments from several sources such as plastics mulch, pharmaceuticals and cosmetics, tire abrasions (tire wear particles), textiles industries (microfibers), sewage sludge, and plastic dumping. Recent studies suggest that the soil has become a significant sink for pollutants released into terrestrial ecosystems and is often contaminated with a mixture of organic and inorganic pollutants. This has gradually caused adverse impacts on soil health and fertility by affecting soil pH, porosity, water-holding capacity, and soil microbial enzymatic activities. Microplastics can interact with the co-existing pollutants of the environments by adsorbing the contaminants onto their surfaces through various intermolecular forces, including electrostatic, hydrophobic, non-covalent, partition effects, van der Waals forces, and microporous filling mechanisms. This subsequently delays the degradation process of existing contaminants, thereby affecting the soil and various ecological activities of the ecosystem. Thus, the present article aims to elucidate the deleterious impact of microplastics and their interactions with other pollutants in the terrestrial ecosystem. This review also addresses the impact of microplastics in disrupting the soil sustainability of the planet.

Plant root hydraulic redistribution (HR) has been widely recognized as a phenomenon that helps alleviate vegetation drought stress. However, a systematic assessment of themagnitude ofHR and its drivers at the global scale are lacking. We collected 37 peer-reviewed papers (comprising 47 research sites) published in 1900-2018 and comprehensively analyzed the magnitude of HR and its underlying factors. We used a weighting method to analyze HR magnitude and its effect on plant transpiration. Machine learning algorithms (boosted regression trees) and structural equation modeling were used to determine the influence of each factor on HR magnitude. We found that the magnitude of HR was 0.249mm H2O d-1 (95% CI, 0.113-0.384) and its contribution to plant transpiration was 27.4% (3-79%). HR varied significantly among different terrestrial biomes and mainly occurred in forests with drier conditions, such as temperate forest ecosystems (HR = 0.502mm H2O d-1), where HR was significantly higher than in other ecosystems (p < 0.01). The magnitude of HR in angiosperms was significantly higher than that in gymnosperms (p < 0.05). The mean magnitude of HR first increased and then decreased with an increase in humidity index; conversely, themeanmagnitude of HR decreased with an increase in water table depth. HR was significantly positively correlated with root length and transpiration. Plant characteristics and environmental factors jointly accounted for 61.0% of the variation in HR, and plant transpiration was the major factor that directly influenced HR (43.1% relative importance; p < 0.001), and soil texture was an important indirect driver of HR. Our synthesis offers a comprehensive perspective of how plant characteristics and environmental factors influence HR magnitude. [ABSTRACT FROM AUTHOR]

Terrestrial ecosystems in China are threatened by land use and future climate change. Understanding the effects of these changes on vegetation and the climate-vegetation interactions is critical for vegetation preservation and mitigation. However, land-use impacts on vegetation are neglected in terrestrial ecosystems exploration, and a deep understanding of land-use impacts on vegetation dynamics is lacking. Additionally, few studies have examined the contribution of vegetation succession to changes in vegetation dynamics. To fill the above gaps in the field, the spatiotemporal distribution of terrestrial ecosystems under the current land use and climate baseline (1970–2000) was examined in this study using the Comprehensive Sequential Classification System (CSCS) model. Moreover, the spatiotemporal variations of ecosystems and their succession under future climate scenarios (the 2030s–2080s) were quantitatively projected and compared. The results demonstrated that under the current situation, vegetation without human disturbance was mainly distributed in high elevation regions and less than 10% of the national area. For future vegetation dynamics, more than 58% of tundra and alpine steppe would shrink. Semidesert would respond to climate change with an expansion of 39.49 × 104 km2, including the succession of the steppe to semidesert. Although some advancement of the temperate forest at the expense of substantial dieback of tundra and alpine steppe is expected to occur, this century would witness a considerable shrinkage of them, especially in RCP8.5, at approximately 55.06 × 104 km2. Overall, a warmer and wetter climate would be conducive to the occurrence and development of the CSCS ecosystems. These results offer new insights on the potential ecosystem response to land use and climate change over the Chinese domain, and on creating targeted policies for effective adaptation to these changes and implementation of ecosystem protection measures. [ABSTRACT FROM AUTHOR]