Separating soil organic carbon (SOC) into mineral-associated organic carbon (MAOC) and particulate organic carbon (POC) enables accurate prediction of SOC vulnerability to land use change (LUC). Here, we synthesize the responses of soil MAOC and POC to LUC, including land restoration and degradation, from 693 soil observations globally. We observed a large increase in soil MAOC and POC after restoration and a greater decline after degradation, but the magnitude and proportion of these two carbon fractions (fMAOC and fPOC) varied with LUC.
View Article and Find Full Text PDFLitter plays a crucial role in soil ecosystems. However, the differences in decomposition between leaf-litter and root-litter and their relative contributions to soil carbon pools and stability are not yet clear. Therefore, we conducted a 450-day in situ decomposition experiment in a semi-arid grassland to investigate the effects of soil biophysical and chemical properties on litter decomposition and to elucidate the dynamics of soil carbon pools during the decomposition process.
View Article and Find Full Text PDFSoil microbial growth, a vital biogeochemical process, governs both the accrual and loss of soil carbon. Here, we investigate the biogeography of soil microbiome potential growth rates and show that microbiomes in resource-rich (high organic matter and nutrients) and acid-neutral soils from cold and humid regions exhibit high potential growth. Conversely, in resource-poor, dry, hot, and hypersaline soils, soil microbiomes display lower potential growth rates, suggesting trade-offs between growth and resource acquisition or stress tolerance.
View Article and Find Full Text PDFThe life strategies of bacterial communities determine their structure and function and are an important driver of biogeochemical cycling. However, the variations in these strategies under different soil resource conditions remain largely unknown. We explored the bacterial life strategies and changes in structure and functions between Antarctic soils and forest (temperate, subtropical, and tropical) soils.
View Article and Find Full Text PDFPlant litter is an important source of soil organic carbon (SOC) in terrestrial ecosystems, and the pattern of litter inputs is also influenced by global change and human activities. However, the current understanding of the impact of changes in litter inputs on SOC dynamics remains contentious, and the mechanisms by which changes in litter inputs affect SOC have rarely been investigated from the perspective of microbial carbon use efficiency (CUE). We conducted a 1-year experiment with litter treatments (no aboveground litter (NL), natural aboveground litter (CK), and double aboveground litter (DL)) in Robinia pseudoacacia plantation forest on the Loess Plateau.
View Article and Find Full Text PDFClimate change is exacerbating drought in arid and semi-arid forest ecosystems worldwide. Soil microorganisms play a key role in supporting forest ecosystem services, yet their response to changes in aridity remains poorly understood. We present results from a study of 84 forests at four south-to-north Loess Plateau sites to assess how increases in aridity level (1- precipitation/evapotranspiration) shapes soil bacterial and fungal diversity and community stability by influencing community assembly.
View Article and Find Full Text PDFMineral protection mechanisms are important in determining the response of particulate organic carbon (POC) and mineral-associated organic carbon (MAOC) to temperature changes. However, the underlying mechanisms for how POC and MAOC respond to temperature changes are remain unclear. By translocating soils across 1304 m, 1425 m and 2202 m elevation gradient in a temperate forest, simulate nine months of warming (with soil temperature change of +1.
View Article and Find Full Text PDFSoil organic carbon (SOC) persistence is predominantly governed by mineral protection, consequently, soil mineral-associated (MAOC) and particulate organic carbon (POC) turnovers have different impacts on the vulnerability of SOC to climate change. Here, we generate the global MAOC and POC maps using 8341 observations and then infer the turnover times of MAOC and POC by a data-model integration approach. Global MAOC and POC storages are Pg C (mean with 5% and 95% quantiles) and Pg C, while global mean MAOC and POC turnover times are yr and yr in the top meter, respectively.
View Article and Find Full Text PDFBackground: Human adipose stromal cells-derived extracellular vesicles (haMSC-EVs) have been shown to alleviate inflammation in acute lung injury (ALI) animal models. However, there are few systemic studies on clinical-grade haMSC-EVs. Our study aimed to investigate the manufacturing, quality control (QC) and preclinical safety of clinical-grade haMSC-EVs.
View Article and Find Full Text PDFPerturbations in soil microbial communities caused by climate warming are expected to have a strong impact on biodiversity and future climate-carbon (C) feedback, especially in vulnerable habitats that are highly sensitive to environmental change. Here, we investigate the impact of four-year experimental warming on soil microbes and C cycling in the Loess Hilly Region of China. The results showed that warming led to soil C loss, mainly from labile C, and this C loss is associated with microbial response.
View Article and Find Full Text PDFSoil respiration the second-largest carbon flux in terrestrial ecosystems, has been extensively studied across a wide range of biomes. Surprisingly, no consensus exist on how acid rain (AR) impacts the spatiotemporal pattern of soil respiration. Therefore, we conducted a meta-analysis using 318 soil respiration and 263 soil respiration temperature sensitivity (Q10) data points obtained from 48 studies to assess the impact of AR on soil respiration components and their Q10.
View Article and Find Full Text PDFTo promote the stability and functionality of native starch from colored highland barley (CHBS), the cross-linked modifications with sodium trimetaphosphate (STMP)/sodium tripolyphosphate (STPP) and citric acid were conducted to prepare CHB resistant starches (CHRSs), whose physicochemical characteristics, digestibility, and lipolysis inhibitory potential were also assessed. Results showed that the resistant starch amounts in CHBS were significantly increased after cross-linking and differed slightly among CHRSs. Citric acid modification of CHBS resulted in significantly higher amylose amounts, solubilities, swelling powers, and water-binding capacities than those under STMP/STPP modification within the cultivars (p < 0.
View Article and Find Full Text PDFHighly variable soil microbial respiration among grasslands has been identified as a major cause of uncertainty in regional carbon (C) budget estimation in the Qinghai-Tibetan Plateau; microbial metabolism mechanisms might explain this variation, but remain elusive. Therefore, we investigated soil CO production in incubated soils and detected the associated functional genes at four sampling sites from two major alpine grasslands on the Qinghai-Tibetan Plateau. The results showed that the cumulative CO emissions from alpine meadow soils were 71 %-83 % lower than those from alpine steppe soils.
View Article and Find Full Text PDFNatural restoration (NR, e.g., secondary succession) and artificial restoration (AR, e.
View Article and Find Full Text PDFAs a key factor of global climate change, precipitation can affect soil respiration. Microorganisms are the key drivers of soil respiration, but the relationship between microbial stoichiometry and respiration in vulnerable habitat areas under different precipitation gradients is unclear. In this study, five precipitation gradients were simulated on a typical abandoned grassland in the loess hilly region.
View Article and Find Full Text PDFIntroduction: Microorganisms regulate soil nitrogen (N) cycling in cropping systems. However, how soil microbial functional genes involved in soil N cycling respond to mulching practices is not well known.
Methods: We collected soil samples from a spring maize field mulched with crop straw (SM) and plastic film (FM) for 10-year and with no mulching (CK) in the Loess Plateau.
Nitrogen (N) deposition in the context of human activities continuously affects the carbon cycle of ecosystems. The effect of N deposition on soil organic carbon is related to the differential responses of different carbon fractions. To investigate the changes in soil organic carbon fraction and its influencing factors in the context of short-term N deposition, four N addition gradients:0 (CK), 1.
View Article and Find Full Text PDFOur results reveal different responses of soil multifunctionality to increased and decreased precipitation. By linking microbial network properties to soil functions, we also show that network complexity and potentially competitive interactions are key drivers of soil multifunctionality.
View Article and Find Full Text PDFIn order to explore the characteristics of organic carbon mineralization and the variation law of organic carbon components of an artificial forest in a loess hilly area, an artificial forest restored for 13 years and the adjacent slope farmland were selected as the research objects, and indoor culture experiments under three different temperature treatments (15, 25, and 35℃) were carried out. The results indicated that the mineralization rate of soil organic carbon decreased sharply at first and then stabilized. The cumulative release of organic carbon increased rapidly in the initial stage of culture and gradually slowed in the later stage.
View Article and Find Full Text PDFSoil Phosphorous (P) availability is a limiting factor for plant growth and regulates biological metabolism in plantation ecosystems. The effect of variations in soil microbial P cycling potential on the availability of soil P during succession in plantation ecosystems is unclear. In this study, a metagenomics approach was used to explore variations in the composition and diversity of microbial P genes along a 45-year recovery sequence of Robinia pseudoacacia on the Loess Plateau, as well soil properties were measured.
View Article and Find Full Text PDFMicrobes play an integral role in forest soil phosphorus (P) cycling. However, the variation of microbial P-cycling functional genes and their controlling factors in forest soils is unclearly. We used metagenomics to investigate changes in the abundance of genes involved in P-starvation response regulation, P-uptake and transport, and P-solubilization and mineralization along the five elevational gradients.
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