论文检索

主页 | 软件工具 | 课题库 | 公众号
:



总访问量:1523938

总访客量:62188

关键词:
Organic Matter |
DOM |
POM |
Soil OM |
Sediment OM |
Organic Carbon |
Organic Nitrogen |
Biomarker |
Humic Substances |
Fulvic Substances |
Humins |
Biochar |
Black Carbon |
GDGT |
Lignin |
Free Radical |
...
最新文章  | 
昨日文章 | 
前日文章
期刊:
Agriculture, Ecosystems & Environment |
Agricultural Water Management |
Applied Geochemistry |
Applied Soil Ecology |
Aquatic Geochemistry |
Atmospheric Research |
Biogeochemistry |
Biogeosciences |
Biology and Fertility of Soils |
Bioresource Technology |
CATENA |
Chemical Engineering Journal |
Chemical Geology |
Chemosphere |
CLEAN - Soil, Air, Water |
Colloids and Surfaces A: Physicochemical and Engineering Aspects |
Deep Sea Research Part II: Topical Studies in Oceanography |
Earth-Science Reviews |
Ecological Engineering |
Ecology Letters |
Ecology |
Ecotoxicology and Environmental Safety |
Environment International |
Environmental Earth Sciences |
Environmental Geochemistry and Health |
Environmental Monitoring and Assessment |
Environmental Pollution |
Environmental Research |
Environmental Science & Technology |
Environmental Science and Pollution Research |
Environmental Science: Processes Impacts |
Environmental Science: Water Research & Technology |
Environmental Toxicology and Chemistry |
Estuarine, Coastal and Shelf Science |
European Journal of Soil Science |
Forest Ecology and Management |
Geochimica et Cosmochimica Acta |
Geoderma |
Geophysical Research Letters |
Global Change Biology |
Global Biogeochemical Cycles |
Groundwater |
Harmful Algae |
International Journal of Coal Geology |
Journal of Environmental Chemical Engineering |
Journal of Environmental Management |
Journal of Environmental Sciences |
Journal of Geophysical Research: Biogeosciences |
Journal of Geophysical Research: Oceans |
Journal of Hazardous Materials |
Journal of Membrane Science |
Journal of Soils and Sediments |
Land Degradation & Development |
Limnology and Oceanography |
Marine Chemistry |
Marine Pollution Bulletin |
Nature Communications |
Nature Geoscience |
Ocean Science Journal |
Oikos |
Organic Geochemistry |
Palaeogeography, Palaeoclimatology, Palaeoecology |
Plant and Soil |
Progress in Oceanography |
Quaternary International |
Science of The Total Environment |
Sedimentary Geology |
Separation and Purification Technology |
Soil and Tillage Research |
Soil Biology and Biochemistry |
Waste Management |
Water Research |
Water, Air, & Soil Pollution |
Wetlands |
...

所有论文

361. 题目: Biochar addition reduces salinity in salt-affected soils with no impact on soil pH: A meta-analysis
文章编号: N24031512
期刊: Geoderma
作者: Xiao Wang, Jianli Ding, Lijing Han, Jiao Tan, Xiangyu Ge, Qiong Nan
更新时间: 2024-03-15
摘要: Salinization remains a major issue in soil degradation, for which biochar is a potential solution. In this -analysis, using 660 paired observations from 99 peer-reviewed articles, we evaluated biochar's effect on salt-affected soils and identified the initial soil properties, biochar properties and experimental factors influencing its efficacy. The results showed that the addition of biochar had a significant ameliorating effect on salt-affected soils. The soil electrical conductivity of saturated paste extract (ECe) was significantly reduced by 13.2%, and such effect was significant in severe salinization soil (rather than slight and moderate salinization). Meanwhile, the soil cation exchange capacity was significantly increased by 17.0%. However, the addition of biochar had no significant impact on soil pH. Model selection analyses further indicated that the level of initial salinity and the type of biochar feedstock were the most important factors regulating the response of soil ECe to biochar addition. In summary, while our study highlights the potential of biochar in ameliorating salt-affected soils, particularly in severely salinized soils, it also underscores the need for more comprehensive research in this field. Additional research is necessary to comprehensively address the significant heterogeneity of biochars, including their thorough characterization. In addition, more studies are required to explore the impact of biochar on both salt-tolerant and non-salt-tolerant plants in salt-affected soils.

362. 题目: Photochemical processes transform dissolved organic matter differently depending on its initial composition
文章编号: N24031511
期刊: Science of the Total Environment
作者: Sheng-Ao Li, Qianru Wang, Hua Ma, Xinghong Cao, Yingyue Song, Fuyi Cui, Andrew J Tanentzap
更新时间: 2024-03-15
摘要: Dissolved organic matter (DOM) is one of the most important fluxes in the global carbon cycle but its response to light exposure remains unclear at a molecular-level. The chemical response of DOM to light should vary with its molecular composition and environmental conditions while some basic hypotheses are still unclear, such as the balance between photobleaching and photo-humification and the question of oxidative properties. Here we exposed aquatic DOM from diverse freshwaters impacted by different levels of anthropogenic activity and algal exudates to environmentally-realistic light conditions. We found that photobleaching occurred in DOM with relatively high initial humic content producing low H/C molecules, whereas DOM with low initial humic content was humified. DOM pools with relatively high initial saturation and low aromaticity were prone to transform towards more unsaturated molecular formulae and high H/C molecules with a distinct decrease of bioavailability. Photo-transformation was mainly influenced by reactive intermediates, with reactive oxygen species (ROS) playing a dominant role in humification when the initial humus content of DOM was high. In contrast, for algal DOM with high protein content, it was likely that the autoxidation of excited state DOM was more important than indirect oxidation involving ROS. Our results reveal how photo-transformation patterns depend on the initial composition of DOM and provide new insights into the role of photochemical processes in biogeochemical cycling of DOM.

363. 题目: Energy stored in soil organic matter is influenced by litter quality and the degree of transformation – A combustion calorimetry study
文章编号: N24031510
期刊: Geoderma
作者: Marcel Lorenz, Thomas Maskow, Sören Thiele-Bruhn
更新时间: 2024-03-15
摘要: The turnover and stabilization of organic matter (OM) in soils depend on mass and energy fluxes. Understanding the energy content of soil organic matter (SOM) is therefore of crucial importance, but this has hardly been studied so far, especially in mineral soils. In this study, combustion calorimetry (bomb calorimetry) was applied to determine the energy content (combustion enthalpy, Δ) of various materials: litter inputs, forest floor layers (OL, OF, OH), and bulk soil and particulate organic matter (POM) from topsoils (0–5 cm). Samples were taken from 35-year-old monocultural stands of Douglas fir (), black pine (), European beech (), and red oak () grown under highly similar soil, landscape and boundary conditions. This allowed to investigate the influence of the degree of transformation and litter quality on the Δ of SOM. Tree species fuel the soil C cycle with high-energy litter (38.9 ± 1.1 kJ gC) and fine root biomass (35.9 ± 1.1 kJ gC). As plant material is transformed to SOM, Δ decreases in the order: OL (36.8 ± 1.6 kJ gC) ≥ OF (35.9 ± 3.7 kJ gC) > OH (30.6 ± 7.0 kJ gC) > 0–5 cm bulk soil (22.9 ± 8.2 kJ gC). It indicates that the energy content of OM decreases with transformation and stabilization, as microorganisms extract energy from organic compounds for growth and maintenance, resulting in lower-energy bulk SOM. The POM fraction has 1.6-fold higher Δ compared to the bulk SOM. Tree species significantly affect Δ of SOM in the mineral soil with the lowest values under beech (12.7 ± 3.4 kJ gC). The energy contents corresponded to stoichiometric and isotopic parameters as proxies for the degree of transformation. In conclusion, litter quality, in terms of elemental composition and energy content, defines the pathway and degree of the energy-driven microbially mediated transformation and stabilization of SOM.

364. 题目: Microbial-explicit processes and refined perennial plant traits improve modeled ecosystem carbon dynamics
文章编号: N24031509
期刊: Geoderma
作者: Danielle M Berardi, Melannie D Hartman, Edward R Brzostek, Carl J Bernacchi, Evan H DeLucia, Adam C von Haden, Ilsa Kantola, Caitlin E Moore, Wendy H Yang, Tara W Hudiburg, William J Parton
更新时间: 2024-03-15
摘要: Globally, soils hold approximately half of ecosystem carbon and can serve as a source or sink depending on climate, vegetation, management, and disturbance regimes. Understanding how soil carbon dynamics are influenced by these factors is essential to evaluate proposed natural climate solutions and policy regarding net ecosystem carbon balance. Soil microbes play a key role in both carbon fluxes and stabilization. However, biogeochemical models often do not specifically address microbial-explicit processes. Here, we incorporated microbial-explicit processes into the DayCent biogeochemical model to better represent large perennial grasses and mechanisms of soil carbon formation and stabilization. We also take advantage of recent model improvements to better represent perennial grass structural complexity and life-history traits. Specifically, this study focuses on: 1) a plant sub-model that represents perennial phenology and more refined plant chemistry with downstream implications for soil organic matter (SOM) cycling though litter inputs, 2) live and dead soil microbe pools that influence routing of carbon to physically protected and unprotected pools, 3) Michaelis-Menten kinetics rather than first-order kinetics in the soil decomposition calculations, and 4) feedbacks between decomposition and live microbial pools. We evaluated the performance of the plant sub-model and two SOM cycling sub-models, Michaelis-Menten (MM) and first-order (FO), using observations of net ecosystem production, ecosystem respiration, soil respiration, microbial biomass, and soil carbon from long-term bioenergy research plots in the mid-western United States. The MM sub-model represented seasonal dynamics of soil carbon fluxes better than the FO sub-model which consistently overestimated winter soil respiration. While both SOM sub-models were similarly calibrated to total, physically protected, and physically unprotected soil carbon measurements, the models differed in future soil carbon response to disturbance and climate, most notably in the protected pools. Adding microbial-explicit mechanisms of soil processes to ecosystem models will improve model predictions of ecosystem carbon balances but more data and research are necessary to validate disturbance and climate change responses and soil pool allocation.

365. 题目: The value of adding black carbon to community monitoring of particulate matter
文章编号: N24031508
期刊: Atmospheric Environment
作者: Rebecca A Sugrue, Chelsea V Preble, James D A Butler, Alaia J Redon-Gabel, Pietro Marconi, Karan D Shetty, Lee Ann L Hill, Audrey M Amezcua-Smith, Boris R Lukanov, Thomas W Kirchstetter
更新时间: 2024-03-15
摘要: Low-cost particulate matter (PM) sensors are increasingly used by researchers, public health agencies, and the public to measure spatial and temporal variations in air pollution, which can inform strategies for community air pollution reduction. While low-cost PM sensors provide a valuable measure of harmful fine particulate matter (PM), a significant portion of ambient PM is typically the secondary product of air pollution emitted by varied sources outside of community boundaries. In contrast, concentrations of black carbon (BC), a component of PM, are directly emitted by a few specific sources, such as diesel engines within communities. Motivated by community organizations seeking to understand persistent sources of local pollution, this study deployed a suite of custom-built BC sensors alongside a network of low-cost PM sensors for four weeks in two seasons at 50 stationary locations in the adjacent cities of Richmond, North Richmond, and San Pablo, California, east of the San Francisco Bay. Concentrations of BC varied more than PM both temporally and spatially. Monthly network-average BC was 3 × higher in winter than late spring, while PM was only 10% lower. In both seasons, average PM concentrations at two-thirds of sites were ±10% of the network average, whereas two-thirds of sites had BC levels ±10% of the network-average concentration. The most and least polluted locations were more persistent across seasons for BC than PM, and the temporal dynamics of BC at these sites were similar, signifying that they are impacted by the same emission sources. Together, these spatiotemporal trends show that BC is a better indicator of the proximity and activity of local pollution sources than PM. Thus, including BC in addition to PM in community monitoring networks can provide additional insights about local sources of air pollution.

366. 题目: Co-removal of CO2 and Hg using corn straw and pine biochar pretreated by hydrothermal technology
文章编号: N24031507
期刊: Separation and Purification Technology
作者: Tianle Zhang, Zhuo Xiong, Yongchun Zhao, Junying Zhang
更新时间: 2024-03-15
摘要: To reduce CO and Hg emission, the comparative research about CO and Hg co-removal performance of corn straw and pine biochar pretreated by hydrothermal technology was carried out. The results show that the specific surface area of corn straw and pine biochar can reach 448.24 m/g and 397.86 m/g, respectively. But in the range of 700–900 °C, pyrolysis temperature has opposite effects on the physical structure of the two types of biochar. Although iron ions can regulate the growth of ultra-micropores through the reduction reaction with matrix carbon during pyrolysis, too high pyrolysis temperature can also cause matrix collapse and ion sintering to hinder the construction of ultra-micropores of biochar. The ultra-microporous homogeneity and volume are main factors affecting the physical adsorption of CO and Hg. The pine biochar prepared at 700 °C (PCH-700) performed the better CO adsorption capacity and mercury removal efficiency (5.35 wt% and around 100 %) at room temperature. The CO trapped on the biochar can be linked to the biochar matrix and form oxygen-containing functional groups, thereby promoting the release of free radical oxygen to achieve the co-removal of CO and Hg.

367. 题目: xuIndirect photodegradation of zinc pyrithione: The effect of chromophoric dissolved organic matter components and seawater factors
文章编号: N24031506
期刊: Journal of Environmental Chemical Engineering
作者: Shu Zhou, Shukai Liu, Xiao Meng, Tianqi Liu, Xiaoyong Shi, Rongguo Su
更新时间: 2024-03-15
摘要: Chromophoric dissolved organic matter (CDOM) is the main photosensitizer in seawater. CDOM can absorb solar radiation extensively and generate reactive intermediates (RIs), including singlet oxygen (O), hydroxyl radicals (HO·), and CDOM triplet states (CDOM), that are favorable for indirect photodegradation of organic pollutants. In the current study, the effect and mechanism of CDOM components on zinc pyrithione (ZnPT) indirect photodegradation were studied. Among the three CDOM isolates (humic acid (JKHA), Suwannee River humic acid (SRHA), and Suwannee River natural organic matter (SRNOM)), JKHA had the highest fluorescence intensity per gram of carbon and the fastest indirect photodegradation rate for ZnPT. Furthermore, the fluorescent components were divided into four terrestrial humic-like components: C1, C2, C3, and C4, by using excitation–emission matrix spectroscopy combined with parallel factor analysis. A notable relationship was found between the four fluorescent components of CDOM and ZnPT indirect photodegradation. The indirect photodegradation rate of ZnPT varied in different types of CDOM solutions, which may be attributed to the different compositions of CDOM. The relative contents of C1 and C4 were significantly higher in JKHA than in the other two CDOMs, and they were the major contributors to the production of CDOM and O, which promoted ZnPT indirect photodegradation. The impact of seawater factors on ZnPT indirect photodegradation was also investigated. The ZnPT indirect photodegradation rate initially decreased and then increased as the pH increased from 5.00 to 11.00. The lowest rate of indirect photodegradation of ZnPT was observed at pH = 9.00. As the salinity was <25‰, in salinity the ZnPT indirect photodegradation rate increased concomitantly with an increase, and pronounced inhibition of ZnPT indirect photodegradation was observed when the salinity was >25‰. Nitrate had a promoting influence on ZnPT indirect photodegradation, whereas HCO, halogen ions, and metal ions all inhibited it.

368. 题目: Interactions between soil structure dynamics, hydrological processes, and organic matter cycling: A new soil-crop model
文章编号: N24031505
期刊: European Journal of Soil Science
作者: Nicholas Jarvis, Elsa Coucheney, Elisabet Lewan, Tobias Klöffel, Katharina H E Meurer, Thomas Keller, Mats Larsbo
更新时间: 2024-03-15
摘要: The structure of soil is critical for the ecosystem services it provides since it regulates many key soil processes, including water, air and solute movement, root growth and the activity of soil biota. Soil structure is dynamic, driven by external factors such as land management and climate and mediated by a wide range of biological agents and physical processes operating at strongly contrasting time-scales, from seconds (e.g., tillage) to many decades (e.g., faunal activity and soil aggregation). In this respect, positive feedbacks in the soil–plant system may lead in the longer term to soil physical degradation or to the recovery of structurally poor soils. As far as we are aware, no existing soil-crop model can account for such processes. In this paper, we describe a new soil-crop model (USSF, Uppsala model of Soil Structure and Function) that accounts for the effects of soil structure dynamics on water and organic matter cycling at the soil profile scale. Soil structure dynamics are expressed as time-varying physical (bulk density, porosity) and hydraulic properties (water retention, hydraulic conductivity) responding to the activity of biological agents (i.e., earthworms, plant roots) and physical processes (i.e., tillage, soil swell-shrink) at seasonal to decadal time-scales. In this first application of the model, we present the results of 30-year scenario simulations that illustrate the potential role and importance of soil structure dynamics for the soil water balance, carbon storage in soil, root growth, and winter wheat yields on two soils (loam and clay) in the climate of central Sweden. A sensitivity analysis was also performed for these two scenarios using the Morris method of elementary effects, which revealed that the most sensitive parameters controlling soil structure dynamics in the USSF model are those determining aggregation induced by organic matter turnover and swell/shrink. We suggest that the USSF model is a promising new tool to investigate a wide range of processes and phenomena triggered by land use and climate change. Results from this study show that feedback in the soil-crop system mediated by the dynamics of soil physical and hydraulic properties are potentially of central importance for long-term predictions of soil water balance, crop production, and carbon sequestration under global change.

369. 题目: Pristine and Fe-functionalized biochar for the simultaneous immobilization of arsenic and antimony in a contaminated mining soil
文章编号: N24031504
期刊: Journal of Hazardous Materials
作者: Jiayi Li, Yurong Gao, Caibin Li, Fenglin Wang, Hanbo Chen, Xing Yang, Paramsothy Jeyakumar, Binoy Sarkar, Zhenbao Luo, Nanthi Bolan, Xiaofei Li, Jun Meng, Hailong Wang
更新时间: 2024-03-15
摘要: This study examined the effectiveness of pristine biochar (BC) and Fe-functionalized biochar (FBC) in remediating As-Sb co-contaminated soil, and revealed the resulting impact on soil enzymatic activities and bacterial communities. Results from incubation experiments showed that the 1.5% FBC treatment reduced the bioavailable As and Sb concentration by 13.5% and 27.1%, respectively, in compared to the control. and increased the proportion of unavailable specifically adsorbed and amorphous Fe-Mn oxide-bound metal(loid) fractions in the treated soil. Among the BC treatments, only the 1.5% BC treatment resulted in a reduction of bioavailable As by 11.7% and Sb by 21.4%. The 0.5% BC treatment showed no significant difference. The FBC achieved high As/Sb immobilization efficiency through Fe-induced electrostatic attraction, π-π electron donor-acceptor coordination, and complexation (Fe–O(H)–As/Sb) mechanisms. Additionally, the 1.5% FBC treatment led to an 80.7% and 108.2% increase in the activities of N-acetyl-β-glucosaminidase and urease in soils, respectively, compared to the control. Furthermore, it significantly increased the abundance of Proteobacteria (15.2%), Actinobacteriota (37.0%), Chloroflexi (21.4%), and Gemmatimonadota (43.6%) at the phylum level. Co-occurrence network analysis showed that FBC was better than BC in increasing the complexity of bacterial communities. Partial least squares path modeling further indicated that the addition of biochar treatments can affect soil enzyme activities by altering soil bacterial composition. This study suggests that FBC application offers advantages in simultaneous As and Sb immobilization and restructuring the bacterial community composition in metal(loid)-contaminated soil.

370. 题目: Dual role of silt and clay in the formation and accrual of stabilized soil organic carbon
文章编号: N24031503
期刊: Soil Biology and Biochemistry
作者: Hai-Ruo Mao, M Francesca Cotrufo, Stephen C Hart, Benjamin W Sullivan, Xuefeng Zhu, Jianchao Zhang, Chao Liang, Mengqiang Zhu
更新时间: 2024-03-15
摘要: Soil organic carbon (SOC) is the largest terrestrial carbon (C) pool and is vulnerable to climate and land-use changes. Promoting the stabilization of SOC will reduce climate change-induced C losses. Mineral-associated organic carbon (MAOC), formed by the association of organic carbon with silt- and clay-sized minerals, is the major stabilized SOC fraction and key to sustaining soil health and mitigating climate change. However, the role of silt and clay in MAOC formation remains unclear in dryland ecosystems where microbes and plants are frequently under water stress. The current paradigm assumes that the main role of silt and clay is to adsorb and aggregate organic compounds. In a semi-arid environment, using a naturally occurring gradient of increasing soil silt and clay content partially due to aeolian dust inputs, we show that silt and clay also enhanced microbial decomposition of plant C inputs and microbial turnover, increasing microbial C inclusion into the MAOC pool. Finer-textured soils had higher soil water availability and higher volume of habitat available to microorganisms. The enhanced microbial processing interacted with changes in plant C inputs to further control the relative contribution of MAOC to SOC. Our results suggest SOC models should include soil textural effects on microbial activities and microbial C production in addition to physical protection of SOC. Our study also suggests that aeolian dust inputs can increase soil silt and clay contents and improve nutrient availability in dryland ecosystems, potentially mitigating the SOC loss under climate change and increasing the resilience of ecosystems to drought.

371. 题目: Permafrost degradation and its consequences for carbon storage in soils of Interior Alaska
文章编号: N24031502
期刊: Biogeochemistry
作者: Patrick Liebmann, Jiří Bárta, Cordula Vogel, Tim Urich, Alexander Kholodov, Milan Varsadiya, Ole Mewes, Stefan Dultz, Muhammad Waqas, Haitao Wang, Olga Shibistova, Georg Guggenberger
更新时间: 2024-03-15
摘要:

Permafrost soils in the northern hemisphere are known to harbor large amounts of soil organic matter (SOM). Global climate warming endangers this stable soil organic carbon (SOC) pool by triggering permafrost thaw and deepening the active layer, while at the same time progressing soil formation. But depending, e.g., on ice content or drainage, conditions in the degraded permafrost can range from water-saturated/anoxic to dry/oxic, with concomitant shifts in SOM stabilizing mechanisms. In this field study in Interior Alaska, we investigated two sites featuring degraded permafrost, one water-saturated and the other well-drained, alongside a third site with intact permafrost. Soil aggregate- and density fractions highlighted that permafrost thaw promoted macroaggregate formation, amplified by the incorporation of particulate organic matter, in topsoils of both degradation sites, thus potentially counteracting a decrease in topsoil SOC induced by the permafrost thawing. However, the subsoils were found to store notably less SOC than the intact permafrost in all fractions of both degradation sites. Our investigations revealed up to net 75% smaller SOC storage in the upper 100 cm of degraded permafrost soils as compared to the intact one, predominantly related to the subsoils, while differences between soils of wet and dry degraded landscapes were minor. This study provides evidence that the consideration of different permafrost degradation landscapes and the employment of soil fractionation techniques is a useful combination to investigate soil development and SOM stabilization processes in this sensitive ecosystem.

372. 题目: A new approach to explore and assess the sustainable remediation of chromium-contaminated wastewater by biochar based on 3E model
文章编号: N24031501
期刊: Chemosphere
作者: Jiang Huang, Xiao Tan, Yue Xie, Xiaoge Wu, Stephen L Dahn, Zhipeng Duan, Imran Ali, Jun Cao, Yinlan Ruan
更新时间: 2024-03-15
摘要: As a cost-effective material, biochar, known as ‘black gold’, has been widely used for environmental applications (EA), including chromium-contaminated wastewater remediation. However, limited reports focused on the multiple impacts of biochar, including energy consumption (EC) and environmental risk (ER). Hence, to recommend biochar as a green material for sustainable development, the three critical units were explored and quantitatively assessed based on an adapted 3E model (EA-EC-ER). The tested biochar was produced by limited-oxygen pyrolysis at 400–700 °C by using three typical biomasses (, phoenix tree, and municipal sludge), and the optimal operational modulus of the 3E model was identified using six key indicators. The findings revealed a significant positive correlation between EC and biochar yield ( < 0.05). The biochar produced by phoenix tree consumed more energy due to having higher content of unstable carbon fractions. Further, high-temperature and low-temperature biochar demonstrated different chromium removal mechanisms. Notably, the biochar produced at low temperature (400 °C) achieved better EA due to having high removal capacity and stability. Regarding ER, pyrolysis temperature of 500 °C could effectively stabilize the ecological risk in all biochar and the biochar produced by depicted the greatest reduction (37-fold). However, the increase in pyrolysis temperature would lead to an increase in global warming potential by nearly 22 times. Finally, the 3E model disclosed that the biochar produced by at 500 °C with low EC, high EA, and low ER had the most positive recommendation index (+78%). Importantly, a rapid assessment methodology was established by extracting parameters from the correlation. Based on this methodology, about eight percent of biochar can be the highest recommended from more than 100 collected peer-related data. Overall, the obtained findings highlighted that the multiple impacts of biochar should be considered to efficiently advance global sustainable development goals.

373. 题目: Organic carbon in wet deposition of an urbanized coastal bay, North China: Flux, sources and biogeochemical implications
文章编号: N24031421
期刊: Marine Pollution Bulletin
作者: Chenlong Feng, Jianwei Xing, Huamao Yuan, Jinming Song, Xuegang Li, Tianrong Zhan, Jun Ma
更新时间: 2024-03-14
摘要: The process of atmospheric organic carbon (OC) entering the ocean through wet deposition plays a crucial role in the global carbon cycle. To gain insights into the biogeochemical dynamics of OC at the land-sea margin, we conducted an extensive four-year investigation on precipitation OC in Jiaozhou Bay (JZB). The results showed that the volume-weighted mean concentration of particulate OC (POC) and dissolved OC (DOC) in precipitation were 0.38 and 2.06 mg C L with an average wet deposition flux of OC for 2666.5 mg C m yr. The source of POC in precipitation is predominantly by the C3 plant emission and burning and fossil fuel combustion. Wet deposition contributed 986.6 t yr of OC of which 506.3 t yr of bioavailable DOC, which could have significant implications for carbon cycle in the JZB. This study could enhance the understanding of the marine atmospheric OC in coastal areas.

374. 题目: Relevance of the organic carbon to clay ratio as a national soil health indicator
文章编号: N24031420
期刊: Geoderma
作者: Eva Rabot, Nicolas P A Saby, Manuel P Martin, Pierre Barré, Claire Chenu, Isabelle Cousin, Dominique Arrouays, Denis Angers, Antonio Bispo
更新时间: 2024-03-14
摘要: The soil organic carbon (SOC) to clay-sized particles ratio (SOC/clay) has recently been selected as an indicator of the soil organic matter status in managed mineral soils within the framework of the European Soil Monitoring Law proposal. This indicator was initially developed to predict soil structural quality in a local study in Switzerland and was subsequently tested at national scales in England and Wales, and in Germany. In this study, we evaluated if the SOC/clay ratio was relevant to assess the structural quality of soils at the national scale in mainland France. We additionally evaluated its variant, SOC/(silt < 20 µm + clay). We confronted SOC/clay and SOC/(silt < 20 µm + clay) to two indicators of soil structure, the soil bulk density and aggregate stability, and we tested the effect of land use and soil type using information from the French Soil Quality Monitoring Network (RMQS). We showed that the SOC/clay and SOC/(silt < 20 µm + clay) were poor indicators of the soil bulk density and aggregate stability. In our analysis, the SOC content was the best indicator of soil structure. Both land use and soil type had an effect on the SOC/clay value. SOC/clay was found to be strongly affected by soil pH with acidic soils consistently being classified as healthy according to the threshold of 1/13 and alkaline soils often being classified as unhealthy. The domain of applicability of SOC/clay excludes soils involving other SOC stabilization mechanisms than associations with the clay fraction and climate is not taken into account. Based on the RMQS dataset, 63 % of cropland, 81 % of permanent crop and 23 % of grassland soils were below the SOC/clay threshold of 1/13, which would classify them as unhealthy according to the European Soil Monitoring Law. We questioned the relevance of the SOC/clay ratio and its proposed threshold of 1/13 as a soil structure indicator, and more broadly as an indicator of the SOC status of healthy soils for all European pedoclimatic contexts. The Soil Monitoring Law leaves the possibility of using correction factors for specific soil types or climatic conditions, which appears necessary for France, because some pedoclimatic contexts will never allow a satisfactory value to be reached.

375. 题目: Exploring hydrological controls on dissolved organic carbon export dynamics in a typical flash flood catchment using a process-based model
文章编号: N24031419
期刊: Science of the Total Environment
作者: Yue Wu, Hang Su, Lei Cheng, Shujing Qin, Kaijie Zou, Yanghe Liu, Jingzhe Zhou, Pan Liu, Lu Zhang
更新时间: 2024-03-14
摘要: The dynamics of dissolved organic carbon (DOC) export from headwater catchments are of critical importance for the global carbon balance and are driven by complex runoff processes. Most previous studies have used statistical relationships between runoff and DOC concentration to estimate DOC export dynamics. Thus, the coupling mechanisms between runoff generation and DOC export dynamics at the process level were obscured in the fitting parameters and have rarely been addressed. In this study, high-frequency (hourly) discharge and DOC export from a typical flash flood experimental headwater catchment with an area of 1.8 km were simulated using a process-based model (INCA-C). The results showed that the INCA-C model successfully captured the hourly dynamics of both discharge and DOC concentrations with a Nash–Sutcliffe efficiency (NSE) of 0.47–0.81 and 0.28–0.70 among moderate events and 0.81–0.85 and 0.19–0.90 among extreme events, respectively. The DOC was exported with distinct concentration dynamics, fluxes, and contributions from the four flow pathways under different storm intensities. At higher intensities, the DOC fluxes were exported by subsurface flows, particularly from shallow organic soil, with greater peaks and shorter time-to-peaks. Exported DOC is primarily sourced from subsurface runoff from the mineral layer (73 %–77 %) during moderate events, whereas it is primarily sourced from subsurface runoff from the organic layer (61 %–79 %) during extreme events. The two contrasting contributions suggest that hydrological pathway controls and DOC dynamic patterns can shift owing to runoff generation influenced by storm intensity. The distinct and variable controls of different flow pathways on DOC export highlight the need to explain the role of hydrology in regulating DOC storm exports through process-based modelling.

376. 题目: Biochar improves fertility in waste derived manufactured soils, but not resilience to climate change
文章编号: N24031418
期刊: Science of the Total Environment
作者: Jennifer M Rhymes, Daniel Evans, Giuliano Laudone, H Kate Schofield, Ellen Fry, Mark F Fitzsimons
更新时间: 2024-03-14
摘要: We present a soil manufactured from waste materials, which could replace the use of peat and topsoil in plant production and reduce the pressure on natural soil resources. We tested the effect of the manufactured soil on ecosystem functions and microbial communities with and without plants present, and with and without biochar addition (Experiment 1). The resilience of the soil in response to drought and flooding, and also the effect of biochar was also tested (Experiment 2). Biochar increased soil C and N regardless of plant presence and negated the effect of the plant on soil peroxidase enzyme activity. The manufactured soil was largely resilient to drought, but not flooding, with negative impacts on microbial communities. Results indicate that biochar could improve soil properties, but not resilience to climatic perturbations. Results suggest that manufactured soils amended with biochar could offer a useful alternative to natural soil in many contexts.

377. 题目: Preferential remineralization of phosphorus from organic matter in river-dominated coastal sediments
文章编号: N24031417
期刊: Science of the Total Environment
作者: Zhongliang Lin, Li Liu, Ergang Lian, Xinyu Jiang
更新时间: 2024-03-14
摘要: In coastal sediments characterized by substantial terrestrial input, the Redfield ratio may not be adequate to determine whether phosphorus (P) is preferentially remineralized relative to carbon (C). Employing a two end-member δC mixing model, we observed a gradual decrease in the fraction of terrestrial organic matter as the distance from the river mouth increased. Consequently, the C/P ratio of sedimentary organic matter before early diagenetic alteration (C/P) decreased from 213 ± 26 to 126 ± 4. In contrast, the C/P ratio of sedimentary organic matter after early diagenetic alteration (C/P) increased from 208 ± 32 to 265 ± 23. The deviation of C/P ratios from C/P ratios suggests that P was preferentially remineralized from organic matter relative to C. Moreover, the degree of preferential remineralization (DPR) of P, represented by (C/P)/(C/P), increased with the distance from the river mouth, suggesting a connection to cross-shelf transport. Besides preferential P remineralization, the control mechanisms for P regeneration from sediments strongly depend on the dissolved oxygen (DO) levels of bottom water. Under oxygenated bottom water (DO >120 μM), the precipitation of Fe oxides reduced benthic DIP flux, resulting in a C/P ratio in flux well above the C/P ratio (1813 ± 725 vs. 213 ± 26). Conversely, when bottom water DO was low (DO<100 μM), the dissolution of Fe oxides and preferential P remineralization increased DIP fluxes, but the precipitation of authigenic apatite suppressed DIP fluxes, leading to C/P ratios in flux approximating C/P ratios (129 ± 35 vs. 158 ± 10 and 200 ± 82 vs. 141 ± 7). In a moderate redox state (100 < DO <120 μM), preferential P remineralization and the dissolution of Fe oxides increased DIP fluxes, resulting in C/P ratios in flux below C/P ratios (29 ± 8 vs. 131 ± 5 and 15 ± 6 vs. 126 ± 4).

378. 题目: Impact of wildfire recurrence on soil properties and organic carbon fractions
文章编号: N24031416
期刊: Journal of Environmental Management
作者: L Salgado, M G Alvarez, A M Díaz, J R Gallego, R Forján
更新时间: 2024-03-14
摘要: The recurrence and severity of wildfire is on the rise due to factors like global warming and human activities. Mediterranean regions are prone to significant wildfire events, which cause extensive damage to ecosystems and soil properties. This study focuses on the municipality of Allande in south-western Asturias (Spain), a region highly affected by recurrent wildfires. In this regard, we sought to examine how the recurrence of such fires influences soil organic carbon fractionation and other soil parameters, such as nitrogen fractionation, pH, and cation exchange capacity. The study involved six sampling plots with between varying fire recurrence levels, from 0 to 4 events between 2005 and 2022. The results revealed some significant effects of wildfires recurrence on soil texture, inorganic elemental composition and CEC, but not on pH and CE. In soil affected by recurrent fires, labile carbon fractions (cold-water extractable & hot-water extractable), and fulvic acid concentrations decreased by up to 36%, 5%, and 45%, respectively in comparison with undisturbed soil. In contrast, humic acid concentration remained stable or increased in soils damaged by fire. Additionally, nitrogen species in soil were observed to decrease significantly in high recurrence scenarios, especially nitrate. On the basis of our findings, we conclude that wildfires impact the distinct fractions of organic carbon and nitrogen in soils and that this effect is aggravated by increasing recurrence.

379. 题目: Driving factors of colored dissolved organic matter dynamics across a complex urbanized estuary
文章编号: N24031415
期刊: Science of the Total Environment
作者: Alana Menendez, Maria Tzortziou
更新时间: 2024-03-14
摘要: The role of estuaries in sourcing and transforming dissolved organic matter - the largest reservoir of organic carbon in the ocean - still presents many unknowns for coastal biogeochemical cycles, and is further complicated by increasing human pressures and a changing climate. Here, we examined the major drivers of colored dissolved organic matter (CDOM) dynamics in Long Island Sound (LIS), a heavily urbanized estuary of National Significance with a storied water quality past. A comprehensive new optical dataset, including measurements of CDOM absorption and fluorescence signatures, was integrated with biological and hydrological measurements to capture the spatiotemporal heterogeneities of LIS, including its urban-to-rural gradient, dynamic river mouths, and blue carbon ecosystems across seasons, following episodic storm events, and over five years. Results reveal longitudinal gradients in both DOM amount and quality. While carbon-rich and humic terrigenous DOM was dominant in the heavily riverine-influenced Central to Eastern LIS, an uncoupling between CDOM absorption () and dissolved organic carbon (DOC) concentration in Western LIS, and a stronger correlation with Chlorophyll-, indicated increased autochthonous CDOM production. Closer to the New York City urban core, was highly correlated to turbidity, consistent with increased wastewater influences. Fluorescence PARAFAC analysis provided strong evidence for seasonal processing of CDOM in LIS, related to increased summertime photochemical degradation of humic-like components and shoulder-season microbial processing. Riverine CDOM export was influenced by discharge amount, residence time, and coastal wetlands acting as additional sources of strongly humic and aromatic organic matter. These measurements allowed us to assess how hydrologic, biological, and anthropogenic processes impact DOM dynamics and, subsequently, biogeochemical variability and trophic status in this complex urbanized estuary, with implications for water quality management and policy. Results discussed here are applicable beyond LIS, as urbanized estuaries globally face similar hydrological and anthropogenic forcings.

380. 题目: Influence of humic acid on the bioaccumulation, elimination, and toxicity of PFOS and TBBPA co-exposure in Mytilus unguiculatus Valenciennes
文章编号: N24031414
期刊: Science of the Total Environment
作者: Qianqian Geng, Liang Zou, Hong Liu, Mengmeng Guo, Fengling Li, Xiangxiang Liu, Hanlin Qin, Xu Wang, Zhijun Tan
更新时间: 2024-03-14
摘要: Tetrabromobisphenol A (TBBPA) and Perfluorooctane sulfonate (PFOS) are emerging contaminants which coexist in marine environments, posing significant risks to ecosystems and human health. The behavior of these contaminants in the presence of dissolved organic matter (DOM), specifically the co-contamination of TBBPA and PFOS, is not well understood. The bioaccumulation, distribution, elimination, and toxic effects of TBBPA and PFOS on thick-shell mussels ( V.), with the absence and presence of humic acid (HA), a typical DOM, were studied. The results showed that the uptake of TBBPA decreased and the uptake of PFOS increased when exposed to 1 mg/L HA. However, at higher concentrations of HA (5 and 25 mg/L), the opposite effect was observed. Combined exposure to HA, TBBPA, and PFOS resulted in oxidative stress in the digestive gland, with the severity of stress dependent on exposure time and HA dose. Histological analysis revealed a positive correlation between HA concentration and tissue damage caused by TBBPA and PFOS. This study provides insights into the influence of HA on the bioaccumulation-elimination patterns and toxicity of TBBPA and PFOS in marine bivalves, offering valuable data for ecological and health risk assessments of combined pollutants in aquatic environments rich in DOM.

 共 22981 条记录  本页 20 条  本页从 361-380 条  19/1150页  首页 上一页  14 15 16 17 18 19 20 21 22 23 24  下一页  末页   

本数据库数据来源自各期刊,所有权归属各期刊。数据仅供分享学习,不作商业用途,特此申明。