Dynamics of sediment-associated nitrogen export from intermittent streams in subtropical forests of southeast China.

The significance of intermittent streams in nutrient loss within forest ecosystems is becoming increasingly critical due to changes in precipitation patterns associated with global climate change. However, few studies have focused on nutrient export from intermittent streams. We conducted continuous sediment collection from intermittent streams from March 2022 to February 2023 to investigate the export pattern and mechanism of sediment-associated nitrogen (N) from intermittent streams of different forest types (composed forest of Castanopsis carlesii (Cas.

Climate warming accelerates carbon release from foliar litter-A global synthesis.

With over one-third of terrestrial net primary productivity transferring to the litter layer annually, the carbon release from litter serves as a crucial valve in atmospheric carbon dioxide concentrations. However, few quantitative global projections of litter carbon release rate in response to climate change exist. Here, we combined a global foliar litter carbon release dataset (8973 samples) to generate spatially explicitly estimates of the response of their residence time (τ) to climate change.

Short-term responses of soil enzyme activities and stoichiometry to litter input in and plantations.

Litter input triggers the secretion of soil extracellular enzymes and facilitates the release of carbon (C), nitrogen (N), and phosphorus (P) from decomposing litter. However, how soil extracellular enzyme activities were controlled by litter input with various substrates is not fully understood. We examined the activities and stoichiometry of five enzymes including β-1,4-glucosidase, β-D-cellobiosidase, β-1,4--acetyl-glucosaminidase, leucine aminopeptidase and acidic phosphatase (AP) with and without litter input in 10-year-old and plantations monthly during April to August, in October, and in December 2021 by using an microcosm experiment.

Trade-off in the partitioning of recent photosynthate carbon under global change.

There may be trade-offs in the allocation patterns of recent photosynthetic carbon (RPC) allocation in response to environmental changes, with a greater proportion of RPC being directed towards compartments experiencing limited resource availability. Alternatively, the allocation of RPC could shift from sources to sinks as plants processing excess photosynthates. It prompts the question: Does the pattern of RPC allocation vary under global changes? If so, is this variation driven by optimal or by residual C allocation strategies? We conducted a meta-analysis by complicating 273 pairwise observations from 55 articles with C or C pulse or continuous labeling to assess the partitioning of RPC in biomass (leaf, stem, shoot, and root), soil pools (soil organic C, rhizosphere, and microbial biomass C) and CO fluxes under elevated CO (eCO ), warming, drought and nitrogen (N) addition.

Effects of vegetation restoration on the concentrations of multiple metal elements in post-mining soils.

Vegetation restoration is vital for soil ecological restoration in post-mining areas, but a global-scale quantitative assessment of its effects on soil metal elements is lacking. Here, we conducted a meta-analysis with 2308 paired observations collected from 137 publications to evaluate vegetation restoration effects on the concentrations of 17 metal elements, namely K, AK (available K), Ca, Na, Mg, Fe, Mn, Zn, Cu, Al, Cr, Co, Ni, Cd, Sb, Hg, and Pb in post-mining soils. We found that (1) vegetation restoration significantly increased the concentrations of K, AK, Ca, Mg and Co by 43.

Global patterns and drivers of lead concentration in inland waters.

Water bodies are important carriers for lead (Pb) biogeochemical cycling, which is a key pathway of Pb transport. Although existing studies on Pb loading in inland waters have developed rapidly, a quantitative assessment of the distribution patterns and drivers of Pb concentration in inland waters at the global scale remains unclear. Here, by analyzing 1790 observations collected from 386 independent publications, we assessed the spatial distribution and drivers of Pb concentration in inland waters worldwide.

The types of microplastics, heavy metals, and adsorption environments control the microplastic adsorption capacity of heavy metals.

Anthropogenic development has released large amounts of microplastics (MPs), which are carriers of migratory heavy metals, into the environment, and heavy metal adsorption by MPs may have strong combined toxic effects on ecosystems. However, until now, a comprehensive understanding of the factors influencing these adsorption capacities of MPs has been lacking. Thus, we used 4984 experimental data points to systematically assess the factors influencing the adsorption strength of 8 types of MPs on 13 types of heavy metals.

[Dynamics of Ca and Mg storage of non-woody debris in a subtropical forest headwater stream during the rainy season.].

Forest headwater streams are the monumental cement for relating habitats of the terrene and water. Nutri-ent dynamics of non-woody debris in stream can directly and indirectly regulate the cycle and transport of forest nutrients, for example, Ca and Mg. In the rainy season (from March to August) of 2021, we monitored the dyna-mics of Ca and Mg storage of non-woody debris in a typical headwater stream in a subtropical forest.

Mycorrhizal association and life form dominantly control plant litter lignocellulose concentration at the global scale.

Lignocellulose is a major component of plant litter and plays a dominant role in regulating the process of litter decomposition, but we lack a global perspective on plant litter initial lignocellulose concentration. Here, we quantitatively assessed the global patterns and drivers of litter initial concentrations of lignin, cellulose, and hemicellulose using a dataset consisting of 6,021 observations collected from 795 independent publications. We found that (1) globally, the median concentrations of leaf litter lignin, cellulose, and hemicellulose were 20.

Litter quality and stream physicochemical properties drive global invertebrate effects on instream litter decomposition.

Plant litter is the major source of energy and nutrients in stream ecosystems and its decomposition is vital for ecosystem nutrient cycling and functioning. Invertebrates are key contributors to instream litter decomposition, yet quantification of their effects and drivers at the global scale remains lacking. Here, we systematically synthesized data comprising 2707 observations from 141 studies of stream litter decomposition to assess the contribution and drivers of invertebrates to the decomposition process across the globe.

Global patterns and drivers of initial plant litter ash concentration.

Ash is a fundamental component of plant litter and plays a vital role in regulating litter decomposition. However, to date, global patterns and underlying mechanisms of initial litter ash concentrations remain unclear. Here, we used 570 observations collected from 104 independent publications to assess the global patterns of initial plant litter ash concentrations and evaluated the effects of mycorrhizal association [arbuscular mycorrhiza (AM) vs.

Changes in soil faunal density and microbial community under altered litter input in forests and grasslands.

Root and foliar litter inputs are the primary sources of carbon and nutrients for soil fauna and microorganisms, yet we still lack a quantitative assessment to evaluate the effects of root and foliar litter on various groups of soil organisms across terrestrial ecosystems. Here, we compiled 978 paired observations from 68 experimental sites to assess the directions and magnitudes of adding and removing foliar and root litter on the soil faunal density and microbial biomass that was evaluated by phospholipid fatty acids (PLFAs) across forests and grasslands worldwide. We found that litter addition had only a marginal effect on soil faunal density but significantly increased the soil total microbial-, fungal- and bacterial-PLFAs by 13%, 14%, and 10%, respectively, across ecosystems, suggesting that the soil microbial community is more sensitive to carbon source addition than soil fauna, particularly in soils with low carbon to nitrogen ratios.

[Nitrogen and phosphorus resorption and stoichiometric characteristics of different tree species in a mid-subtropical common-garden, China.].

To understand the nutrient use strategies of 11 tree species in a subtropical common-garden, we measured the specific leaf area, nitrogen (N) and phosphorus (P) resorption and stoichiometric characteristics of leaves in August 2019. The results showed that the specific leaf area, N and P concentrations in mature and senescent leaves of evergreen broadleaved (, , , , and ) and coniferous species ( and ) were lower than those of deciduous broadleaved species (, and ). In contrast, C:N and C:P in mature leaves of evergreen broadleaved and coniferous species were significantly higher than those of deciduous broadleaved species.

Dsk2 involves in conidiation, multi-stress tolerance and thermal adaptation in Beauveria bassiana.

Dsk2 is a nuclear-enriched ubiquitin-like polyubiquitin-binding protein that regulates protein degradation in yeast but has not been explored yet in filamentous fungi, such as Beauveria bassiana. Here, we report Beauveria bassiana Dsk2 located both in the nucleus and in cytoplasm of hyphal cells. Deletion of Dsk2 resulted in mild growth defect on scant media with various carbon/nitrogen sources and dramatic attenuation in conidiation capability at optimal condition.

Global patterns and drivers of rainfall partitioning by trees and shrubs.

Spatiotemporal redistribution of incident rainfall in vegetated ecosystems results from the partitioning by plants into intercepted, stemflow, and throughfall fractions. However, variation in patterns and drivers of rainfall partitioning across global biomes remains poorly understood, which limited the ability of climate models to improve the predictions of biome hydrological cycle under global climate change scenario. Here, we synthesized and analyzed the partitioning of incident rainfall into interception, stemflow, and throughfall by trees and shrubs at the global scale using 2430 observations from 236 independent publications.

Non-target Effects of Naphthalene on the Soil Microbial Biomass and Bacterial Communities in the Subalpine Forests of Western China.

Naphthalene is a biocide of soil fauna, particularly of soil arthropods, that has been widely applied to test the functional roles of soil fauna in soil processes. However, whether the use of naphthalene to expel soil fauna has a non-target effect on soil bacteria in subalpine forests remains unclear. We conducted a naphthalene treatment experiment to explore the effects of naphthalene on the soil bacterial community in subalpine forest soil.

Effects of naphthalene on soil fauna abundance and enzyme activity in the subalpine forest of western Sichuan, China.

Naphthalene has been widely used to study the role of soil fauna, but its potential non-target effects on soil enzyme activity remain unknown in subalpine forests. We added naphthalene for two years and determined the effect of such additions on the abundance of soil fauna and soil enzyme activities (β-glucosidase, cellobiohydrolase, invertase, peroxidase, polyphenol oxidase, N-acetyl-β-D-glucosaminidase, leucine arylamidase, urease, nitrate reductase and nitrite reductase) in a subalpine forest. Naphthalene could efficiently suppress the individual density and population of soil fauna in situ.

Litter removal reduced soil nitrogen mineralization in repeated freeze-thaw cycles.

Repeated freeze-thaw cycles (FTCs) can alter the relationships between plant litter and soil nitrogen (N) mineralization in subalpine ecosystems, but little information is available about the underlying mechanisms. Therefore, a controlled soil incubation experiment was carried out to study the effects of litter removal on soil N mineralization during FTCs, and the results indicated that FTCs promoted soil N mineralization more than the continuously frozen or nonfrozen condition did. Litter removal promoted soil ammonium N (NH-N) and dissolved organic N (DON) as well as the cumulative N mineralization (CNM) and ammonification, but it reduced the soil microbial biomass N (MBN) in the early stage of FTCs.

Nitrogen additions stimulate litter humification in a subtropical forest, southwestern China.

Despite the importance of nitrogen (N) deposition for soil biogeochemical cycle, how N addition affects the accumulation of humic substances in decomposing litter still remains poorly understood. A litterbag experiment was conducted to assess the potential effects of N addition (0 kg·N·ha·year, 20 kg·N·ha·year and 40 kg·N·ha·year) on mass remaining and humification of two leaf litter (Michelia wilsonii and Camptotheca acuminata) in a subtropical forest of southwestern China. After one year of decomposition, litter mass was lost by 38.

Immobilization of heavy metals during aquatic and terrestrial litter decomposition in an alpine forest.

Plant litter decomposition is an important pathway of heavy metal cycling in forested soil and watershed ecosystems globally, but is so far an overlooked aspects in the existing literature. To investigate the temporal dynamics of heavy metals in decomposing litter, we conducted a two-year field experiment using litterbag method across aquatic and terrestrial ecosystems in an alpine forest on the eastern Tibetan Plateau. Using multigroup comparisons of structural equation modeling with different litter mass-loss intervals, we assessed the direct and indirect effects of several biotic and abiotic factors on the release rates of lead (Pb), cadmium (Cd), and chromium (Cr).

Declines in methane uptake in forest soils.

Forest soils are a sink for atmospheric methane (CH) and play an important role in modulating the global CH budget. However, whether CH uptake by forest soils is affected by global environmental change is unknown. We measured soil to atmosphere net CH fluxes in temperate forests at two long-term ecological research sites in the northeastern United States from the late 1990s to the mid-2010s.

Does foliar nutrient resorption regulate the coupled relationship between nitrogen and phosphorus in plant leaves in response to nitrogen deposition?

Nutrient resorption from senescing leaves is an important process of internal nutrient cycling in plants, but the patterns of nutrient resorption and the coupled relationship between nitrogen (N) and phosphorus (P) in plant leaves as affected by N deposition remain unclear. We analysed the effects of N addition on the nutrient resorption and coupled relationship between N and P in plant leaves under different nutrient-limited conditions based on a global meta-analysis. Globally, the mean N resorption efficiency (NRE) and P resorption efficiency (PRE) under natural conditions were 47.

Temporal dynamics of phosphorus during aquatic and terrestrial litter decomposition in an alpine forest.

Plant litter decomposition in forested soil and watershed is an important source of phosphorus (P) for plants in forest ecosystems. Understanding P dynamics during litter decomposition in forested aquatic and terrestrial ecosystems will be of great importance for better understanding nutrient cycling across forest landscape. However, despite massive studies addressing litter decomposition have been carried out, generalizations across aquatic and terrestrial ecosystems regarding the temporal dynamics of P loss during litter decomposition remain elusive.

The effect of canopy exchange on input of base cations in a subalpine spruce plantation during the growth season.

Canopy exchange is one of the most important processes involved in the internal transfer of elements in forest ecosystems. However, little information is available on how canopy exchange influences the input of base cations in subalpine forests. Therefore, the concentrations and fluxes of base cations in throughfall and stemflow were investigated from August 2015 to July 2016 (except for the frozen season) in a representative subalpine spruce plantation in the eastern Tibet Plateau.