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17641. 题目: Improved removal performance of Gram-negative and Gram-positive bacteria in sand filtration system with arginine modified biochar amendment
文章编号: N22011306
期刊: Water Research
作者: Mengya Zhang, Lei He, Xiangwei Zhang, Shuai Wang, Boaiqi Zhang, Lichun Hsieh, Kun Yang, Meiping Tong
更新时间: 2022-01-13
摘要: Bacterial removal by sand filtration system is commonly inefficient due to the low bacterial adsorption capacity of sand. To improve the bacterial removal performance, biochar fabricated at different temperatures (400 °C, 550 °C and 700 °C) and arginine modified biochar were added into sand filtration columns as filter layers (0.5 and 1 wt%). Addition of biochar into sand columns could improve the removal efficiency for both Escherichia coli and Bacillus subtilis under both slow (4 m/day) and fast (240 m/day) filtration conditions. Bacterial removal efficiency in sand columns with the addition of biochar fabricated at 700 °C were higher than those fabricated at 400 °C and 550 °C due to its best bacterial adsorption capacity. Modification of biochar with arginine could further improve the bacterial removal performance. Specifically, complete bacterial removal (1.35 × 107 ± 10% cells/mL) could be achieved under both slow and fast filtration conditions in sand columns with 1 wt% arginine functionalized biochar amendment. The enhanced bacterial adsorption capacity mainly contributed to the increased bacterial capture performance in columns with addition of arginine-modified biochar. Bacteria more tightly bounded with arginine-modified biochar than bulk biochar. Moreover, complete bacterial removal with the copresence of 5 mg/L humic acid in suspensions was acquired in columns with addition of 1 wt% arginine-modified biochar. Efficient bacterial removal in actual river water, multiple filtration cycles as well as longtime injection duration (100 pore volumes injection) was also obtained. The results of this study demonstrated that arginine-modified biochar had great potential to treat water contaminated by pathogenic bacteria.

17642. 题目: The coupling interaction of soil organic carbon stock and water storage after vegetation restoration on the Loess Plateau, China
文章编号: N22011305
期刊: Journal of Environmental Management
作者: Yuxuan Chen, Tianxing Wei, Kang Ren, Guoliang Sha, Xin Guo, Yanchao Fu, Huan Yu
更新时间: 2022-01-13
摘要: Vegetation restoration may increase the soil organic carbon stock (SOCS) but decrease the soil water storage (SWS) of terrestrial ecosystems in arid and semiarid regions. To guarantee the sustainability of restoration, it is critical to evaluate the coupling interaction of SOCS and SWS. Here, we examined the spatial distributions of SOCS and SWS across a 0–200 cm soil profile in a grassland, forestland and shrubland on the Loess Plateau and determined the driving factors that affected their variations. Our results showed that SOCS and SWS varied across the 0–200 cm soil profile and considerably accumulated in the deep soil layers (100–200 cm). In comparison to SOCS, SWS generally had higher relative benefits in most studied plant communities, which ensured sustainable restoration. In addition, land use played a less important role than local environmental conditions in determining the variations in SOCS and SWS. Specifically, the interaction between SOCS and SWS was mainly strong in the surface soil layers (0–20 cm). Topography was a predominant factor that affected SOCS and SWS in the deep soil layers (100–200 cm), while soil texture was a stable driving factor influencing their variations across the whole soil profile (0–200 cm). Given the low moisture consumption of grasslands and the lowest root mean square deviation (RMSD) of Hippophae rhamnoides, we proposed an advanced scenario for ecological restoration on the Loess Plateau: establishing reasonably large Hippophae rhamnoides patches with fewer edges in a contiguous grassland matrix. Furthermore, this scenario should be tailored to local environmental conditions, such as soil water, texture and topography, followed by natural vegetation succession.

17643. 题目: Modeling the formation of trihalomethanes in rural and semi-urban drinking water distribution networks of Costa Rica
文章编号: N22011304
期刊: Environmental Science and Pollution Research
作者: Daniel Enrique Kelly-Coto, Alejandra Gamboa-Jiménez, Diana Mora-Campos, Pablo Salas-Jiménez, Basilio Silva-Narváez, Joaquín Jiménez-Antillón, Macario Pino-Gómez, Luis Guillermo Romero-Esquivel
更新时间: 2022-01-13
摘要: Chlorination is one of the most important stages in the treatment of drinking water due to its effectiveness in the inactivation of pathogenic organisms. However, the reaction between chlorine and natural organic matter (NOM) generates harmful disinfection by-products (DBPs), such as trihalomethanes (THMs). In this research, drinking water quality data was collected from the distribution networks of 19 rural and semi-urban systems that use water sources as springs, surfaces, and a mixture of both, in three provinces of Costa Rica from April 2018 to September 2019. Twelve models were developed from four data sets: all water sources, spring, surface, and a mixture of spring and surface waters. Linear, logarithmic, and exponential multivariate regression models were developed for each data set to predict the concentration of total trihalomethanes (TTHMs) in the distribution networks. Concentrations of TTHMs were found between < 0.20 and 91.31 µg/L, with chloroform being the dominant species accounting for 62% of TTHMs on average. Turbidity, free residual chlorine, total organic carbon (TOC), dissolved organic carbon (DOC), and ultraviolet absorbance at 254 nm (UV254) showed a significant correlation with TTHMs. In all the data sets the linear models presented the best goodness-of-fit and were moderately robust. Four models, the best of each data set, were validated with data from the same systems, and, according to the criteria of R2, standard error (SE), mean square error (MSE), and mean absolute error (MAE), spring water and mixed spring/surface water models showed a satisfactory level of explanation of the variability of the data. Moreover, the models seem to better predict TTHM concentrations below 30 µg/L. These models were satisfactory and could be useful for decision-making in drinking water supply systems.

17644. 题目: Biochar considerably increases the easily available water and nutrient content in low-organic soils amended with compost and manure
文章编号: N22011303
期刊: Chemosphere
作者: Samar Seyedsadr, Václav Šípek, Lukáš Jačka, Michal Sněhota, Luke Beesley, Michael Pohořelý, Martin Kovář, Lukáš Trakal
更新时间: 2022-01-13
摘要: The soil hydraulic properties of two low-organic soils (Fluvisol; Regosol) were investigated following their amendment with biochar alone or in combination with manure, compost and co-composted biochar. Self-irrigating boxes containing the soil and amendment combinations were purposed with a battery of soil moisture sensors as well as soil porewater sampling devices. Static sampling determined bulk density, porosity and derived soil water retention curves. The aim of this study was to identify the most advantageous amendment combinations to enhance soil water retention whilst simultaneously avoiding excessive nutrient leaching arising, primarily, from manure application. Biochar significantly decreased bulk density and increased total porosity when compared to compost in the Fluvisol, whereas manure affected the greatest changes in the Regosol. All of the tested amendments adjusted the shape or extent of the soil water retention curves, but biochar addition resulted in the greatest increase (⁓50%) in easily available water content (for plants) in both soils, when compared to the control. Saturated hydraulic conductivity was, however, not changed by any of the amendments which reflects a lack of influence on infiltration. An enhancement in nutrient retention occurred in some of the soil amendment configurations, such as for co-composted biochar at 2% dosage and 5% manure-biochar mixture, as revealed by porewater analysis. In summary, the application of biochar with and without additional compost and manure can enhance soil water retention in low-organic soils whilst maintaining or enhancing nutrient retention. Such finding supports the application of mixed organic amendments to low-organic (and therefore drought-prone) arable soils.

17645. 题目: Prediction of soil organic matter using different soil classification hierarchical level stratification strategies and spectral characteristic parameters
文章编号: N22011302
期刊: Geoderma
作者: Xiangtian Meng, Yilin Bao, Xinle Zhang, Xiang Wang, Huanjun Liu
更新时间: 2022-01-13
摘要: Whether a finer soil classification hierarchical stratification strategy and the spectral characteristic parameters (SCPs) that describe the shape of the spectral curve can be used to improve the prediction accuracy of soil organic matter should be clarified. We measured the visible, near-infrared and shortwave infrared (VIS-NIR-SWIR, 400 – 2500 nm) spectral reflectance of 322 topsoil samples. The spectral reflectance was converted to continuum removal curves, and then, SCPs were extracted based on the curves. According to the results of the Second National Soil Survey of China, the samples were divided into 4 great groups or 8 genus, and a variety of stratification strategies were constructed based on great group (GR-S), genus (GE-S), spectral similarity (SS-S) and decision tree model (DT-S). A local random forest model was established to evaluate the performance of different stratification strategies and input variables. Our results are described as follows: (1) In different stratification strategies, the SOM prediction model based on DT-S exhibits the highest accuracy, followed by the SOM prediction models based on GE-S and SS-S; the SOM prediction model based on GR-S exhibits the lowest accuracy; (2) among the different input variables, the root mean squared error (RMSE) and coefficient of determination (R2) of the best SOM model predicted by SCPs are 5.18 g kg−1 and 0.89, respectively. Compared with the original reflectance based on the nonstratified strategy, the RMSE decreases by 4.88 g kg−1 and R2 increases by 0.32. The study results highlight the advantages of refining the soil hierarchy, which is helpful for identifying the differences in soils at the regional scale and analysing the relationship between stratification results and the characteristics of the soil environment to obtain a highly accurate prediction model.

17646. 题目: Engineered biochar: A multifunctional material for energy and environment
文章编号: N22011301
期刊: Environmental Pollution
作者: Mukesh Kumar Awasthi
更新时间: 2022-01-13
摘要: Biochar is a stable carbon-rich product loaded with upgraded properties obtained by thermal cracking of biomasses in an oxygen-free atmosphere. The pristine biochar is further modified to produce engineered biochar via various physical, mechanical, and chemical methods. The hasty advancement in engineered biochar synthesis via different technologies and their application in the field of energy and environment is a topical issue that required an up-to-date review. Therefore, this review deals with comprehensive and recent mechanistic approaches of engineered biochar synthesis and its further application in the field of energy and the environment. Synthesis and activation of engineered biochar via various methods has been deliberated in brief. Furthermore, this review systematically covered the impacts of engineered biochar amendment in the composting process, anaerobic digestion (AD), soil microbial community encouragement, and their enzymatic activities. Finally, this review provided a glimpse of the knowledge gaps and challenges associated with application of engineered biochar in various fields, which needs urgent attention in future research.

17647. 题目: Plant organic matter inputs exert a strong control on soil organic matter decomposition in a thawing permafrost peatland
文章编号: N22011226
期刊: Science of The Total Environment
作者: Rachel M. Wilson, Moira A. Hough, Brittany A. Verbeke, Suzanne B. Hodgkins, Jeff P. Chanton, Scott D. Saleska, Virginia I. Rich, Malak M. Tfaily, Gene Tyson, Matthew B. Sullivan, Eoin Brodie, William J. Riley, Ben Woodcroft, Carmody McCalley, Sky C. Dominguez, Patrick M. Crill, Ruth K. Varner, Steve Frolking, William T. Cooper
更新时间: 2022-01-12
摘要: Peatlands are climate critical carbon (C) reservoirs that could become a C source under continued warming. A strong relationship between plant tissue chemistry and the soil organic matter (SOM) that fuels C gas emissions is inferred, but rarely examined at the molecular level. Here we compared Fourier transform infrared (FT-IR) spectroscopy measurements of solid phase functionalities in plants and SOM to ultra-high-resolution mass spectrometric analyses of plant and SOM water extracts across a palsa-bog-fen thaw and moisture gradient in an Arctic peatland. From these analyses we calculated the C oxidation state (NOSC), a measure which can be used to assess organic matter quality. Palsa plant extracts had the highest NOSC, indicating high quality, whereas extracts of Sphagnum, which dominated the bog, had the lowest NOSC. The percentage of plant compounds that are less bioavailable and accumulate in the peat, increases from palsa (25%) to fen (41%) to bog (47%), reflecting the pattern of percent Sphagnum cover. The pattern of NOSC in the plant extracts was consistent with the high number of consumed compounds in the palsa and low number of consumed compounds in the bog. However, in the FT-IR analysis of the solid phase bog peat, carbohydrate content was high implying high quality SOM. We explain this discrepancy as the result of low solubilization of bog SOM facilitated by the low pH in the bog which makes the solid phase carbohydrates less available to microbial decomposition. Plant-associated condensed aromatics, tannins, and lignin-like compounds declined in the unsaturated palsa peat indicating decomposition, but lignin-like compounds accumulated in the bog and fen peat where decomposition was presumably inhibited by the anaerobic conditions. A molecular-level comparison of the aboveground C sources and peat SOM demonstrates that climate-associated vegetation shifts in peatlands are important controls on the mechanisms underlying changing C gas emissions.

17648. 题目: Relationships between riverine and terrestrial dissolved organic carbon: Concentration, radiocarbon signature, specific UV absorbance
文章编号: N22011225
期刊: Science of The Total Environment
作者: Edward Tipping, Jessica L. Elias, Patrick O. Keenan, Rachel C. Helliwell, Nikolai Pedentchouk, Richard J. Cooper, Sarah Buckingham, Egil Gjessing, Philippa Ascough, Charlotte L. Bryant, Mark H. Garnett
更新时间: 2022-01-12
摘要: The transfer of dissolved organic carbon (DOC) from land to watercourses plays a major role in the carbon cycle, and in the transport and fate of associated organic and inorganic contaminants. We investigated, at global scale, how the concentrations and properties of riverine DOC depend upon combinations of terrestrial source solutions. For topsoil, subsoil, groundwater and river solutions in different Köppen-Geiger climatic zones, we compiled published and new values of DOC concentration ([DOC]), radiocarbon signature (DO14C), and specific UV absorbance (SUVA). The average value of each DOC variable decreased significantly in magnitude from topsoil to subsoil to groundwater, permitting the terrestrial sources to be distinguished. We used the terrestrial data to simulate the riverine distributions of each variable, and also relationships between pairs of variables. To achieve good matches between observed and simulated data, it was necessary to optimise the distributions of water fractions contributed by each of the three terrestrial sources, and also to reduce the mean input terrestrial [DOC] values, to about 60% of the measured ones. One possible explanation for the required lowering of the modelled terrestrial [DOC] values might be unrepresentative sampling of terrestrial DOC, including dilution effects; another is the loss of DOC during riverine transport. High variations in simulated riverine DOC variables, which match observed data, are due predominantly to variations in source solution values, with a lesser contribution from the different combinations of source waters. On average, most DOC in rivers draining catchments with forest and/or grass-shrub land cover comes in similar amounts from topsoil and subsoil, with about 10% from groundwater. In rivers draining croplands, subsoil and groundwater solutions are the likely dominant DOC sources, while in wetland rivers most DOC is from topsoil.

17649. 题目: Effects of burning rice straw residue on-field on soil organic carbon pools: Environment-friendly approach from a conventional rice paddy in central Viet Nam
文章编号: N22011224
期刊: Chemosphere
作者: Nguyen-Sy Toan, Do Hong Hanh, Nguyen Thi Dong Phuong, Phan Thi Thuy, Pham Duy Dong, Nguyen Thanh Gia, Le Duc Tam, Tran Thi Ngoc Thu, Do Thi Van Thanh, Kuan Shiong Khoo, Pau Loke Show
更新时间: 2022-01-12
摘要: Rice straw residue management is still facing many problems worldwide. This study used two environmentally friendly methods to investigate the effects of rice straw burning activity on water-extracted carbohydrate content in long-term paddy soil. Soil samples were collected at a depth within 0–15 cm at the paddy field before and after burning rice straw (pre-burning and post-burning), then extracted by distilled water at the ratio of 1:10 (soil: water) for measuring hot water (at 80 °C) and water extracted carbohydrate (at 25 °C) (HECH and WECH). The results showed that burning rice straw did not alter soil organic carbon (SOC); however, soil pH increased approximately 8.3%. Meanwhile, WECH and HECH ranged from 233 to 630 mg kg−1, with the highest HECH in Pre-burning treatment, while the lowest amount addressed WECH of Post-burning treatment. Extracted carbohydrate decreased after burning rice straw compared to Pre-burning soil. On the other hand, hot water increased 39–58% of carbohydrates compared to water extraction. We conclude that burning rice straw did not affect SOC but tends to reduce their labile carbon pools, and the heating process likely degrade part of SOC when extracted at high temperatures.

17650. 题目: A snapshot on trihalomethanes formation in urban stormwater: Implications for its adequacy as an alternative water resource
文章编号: N22011223
期刊: Journal of Environmental Chemical Engineering
作者: Nian Hong, Yuqing Li, Jiachen Liu, Mengting Yang, An Liu
更新时间: 2022-01-12
摘要: Urban stormwater is an important alternative water resource. In order to ensure their reuse safety, stormwater disinfection is necessary to reduce biological risk. However, disinfection by-products (DBPs) generation might threaten their reuse safety. So far, an in-depth understanding of DBPs generation for urban stormwater is extremely limited. A snapshot study was carried out on water quality and trihalomethanes (THMs, one of the most concerned DBP types) formation potential of roof stormwater and road stormwater by comparing to surface water (indirectly representing sources of drinking water) and reclaimed water. The research results indicated that the dissolved organic matters (the precursor of DBPs) had different concentrations and components in urban stormwater from surface water and reclaimed water. The THMs formation potential of urban stormwater, particularly roof stormwater, were lower than drinking water and most reclaimed water samples. These outcomes highlight the potential of reusing urban stormwater in the perspective of DBPs’ generation and can provide preliminary information and guidance for urban stormwater disinfection and contribute to ensuring stormwater reuse safety.

17651. 题目: Deep learning-based national scale soil organic carbon mapping with Sentinel-3 data
文章编号: N22011222
期刊: Geoderma
作者: Omosalewa Odebiri, Onisimo Mutanga, John Odindi
更新时间: 2022-01-12
摘要: Mapping of soil organic carbon (SOC) at the regional level is critical for climate change policy and the mitigation of its adverse effects. However, reliable SOC estimates particularly over a large extent remains a major challenge due to among others limited sample points, quality of simulation data and the algorithm adopted. Remote sensing (RS) strategies have emerged as a suitable alternative to field and laboratory SOC determination, especially at large spatial extent. The use of Sentinel-3 sensor, the latest of the Sentinel series is minimal and has not been fully developed, despite its impressive attributes that include high spectral-temporal resolution and large coverage. Compared to linear and classical ML models, deep learning (DL) models offer a considerable improvement in data analysis due to their ability to extract more representative features and identify complex spatial patterns associated with big data. Yet, there is paucity in literature on the application of dl-based remote sensing strategies for SOC prediction. Consequently, this study adopted a deep neural network (DNN) to predict SOC at a national scale, using Sentinel-3 image, and compared the results with random forest (RF), support vector machine (SVM) and artificial neural network (ANN) models. The models were trained based on 10-fold cross-validation with 1936 soil samples and 31 predictors. The DNN model generated the best result with a root mean square error (RMSE) of 10.35 t/ha (26 % of the mean), followed by RF (RMSE = 11.2 t/ha), ANN (RMSE = 11.6 t/ha) and SVM (RMSE = 13.6 t/ha). The analytical prowess of the DNN, together with its ability to handle big data by learning patterns through a series of hidden layers (10) to draw conclusions, gives it an edge over other classical ML models. The study concluded that the DNN model with Sentinel-3 data is promising and provides an effective framework for continuous national level SOC modelling.

17652. 题目: Advances on tailored biochar for bioremediation of antibiotics, pesticides and polycyclic aromatic hydrocarbon pollutants from aqueous and solid phases
文章编号: N22011221
期刊: Science of The Total Environment
作者: Anil Kumar Patel, Reeta Rani Singhania, Anugunj Pal, Chiu-Wen Chen, Ashok Pandey, Cheng-Di Dong
更新时间: 2022-01-12
摘要: Biochar is gaining incredible importance for remediation applications due to their attractive removal properties. Moreover, it is becoming ecofriendly, cost-effective and sustainable bioadsorbents towards replacing expensive activated carbons. Studies reveal biochar effectiveness for removal of important and potentially severe organic pollutants such as antibiotics and pesticides. Recent research advancements on biochar modification (physical, chemical and biological) opens greater opportunity to form tailored biochar with improved surface properties than their native forms for offering better removal efficiencies. Further attentions paid towards emergent new modification methods to cover broad-spectrum pollutants using tailored biochar. Current review aims to summarize recent updates upon biochar tailoring, comparative account of tailored biochars removal efficiencies with respect to their native forms and to provide in-depth discussion covering specific interactions of tailored biochars with antibiotics, polycyclic aromatic hydrocarbons (PAHs) and pesticides for their effective removals and degradation from polluted environments. Application of inducer compounds e.g., peroxymonosulfate and sodium percarbonate further improved the biochar role towards degradation of toxic organic pollutants into their less or nontoxic forms. Biochar engineered with specific metals enable them for the same role without inducer compounds. Moreover, microbial interactions with biochar not only improve the bioremediation level further but also degrade the pollutants from the environment and open up better environmental and socio-economic prospects. Application of green, cost-effective and sustainable biochar for remediation of environmentally potential organic pollutants offers economical treatment methods as well as safe environment. These benefits are inline with global trends towards developing a sustainable process for biocircular economy.

17653. 题目: Co-transport and co-release of Eu(III) with bentonite colloids in saturated porous sand columns: Controlling factors and governing mechanisms
文章编号: N22011220
期刊: Environmental Pollution
作者: Zhen Xu, Duoqiang Pan, Qingfeng Tang, Xiaoyan Wei, Chunli Liu, Xiaolong Li, Ximeng Chen, Wangsuo Wu
更新时间: 2022-01-12
摘要: Accurate prediction of the colloid-driven transport of radionuclides in porous media is critical for the long-term safety assessment of radioactive waste disposal repository. However, the co-transport and corelease process of radionuclides with colloids have not been well documented, the intrinsic mechanisms for colloids-driven retention/transport of radionuclides are still pending for further discussion. Thus the controlling factors and governing mechanisms of co-transport and co-release behavior of Eu(III) with bentonite colloids (BC) were discussed and quantified by combining laboratory-scale column experiments, colloid filtration theory and advection dispersion equation model. The results showed that the role of colloids in facilitating or retarding the Eu(III) transport in porous media varied with cations concentration, pH, and humic acid (HA). The transport of Eu(III) was facilitated by the dispersed colloids under the low ionic strength and high pH conditions, while was impeded by the aggregated colloids cluster. The enhancement of Eu(III) transport was not monotonically risen with the increase of colloids concentration, the most optimized colloids concentration in facilitating Eu(III) transport was approximately 150 mg L−1. HA showed significant promotion on both Eu(III) and colloid transport because of not only its strong Eu(III) complexion ability but also the increased dispersion of HA-coated colloid particles. The HA and BC displayed a synergistic effect on Eu(III) transport, the co-transport occurred by forming the ternary BC-HA-Eu(III) hybrid. The transport patterns could be simulated well with a two-site model that used the advection dispersion equation by reflecting the blocking effect. The retarded Eu(III) on the stationary phase was released and remobilized by the introduction of colloids, or by a transient reduction in cation concentration. The findings are essential for predicting the geological fate and the migration risk of radionuclides in the repository environment.

17654. 题目: Effects of pyrolysis temperature on biochar’s characteristics and speciation and environmental risks of heavy metals in sewage sludge biochars
文章编号: N22011219
期刊: Environmental Technology & Innovation
作者: Xin Zhang, Baowei Zhao, Hui Liu, Yue Zhao, Liujun Li
更新时间: 2022-01-12
摘要: Sewage sludge pyrolysis into biochar is an effective way to realize sludge harmless and resourceful utilization. The study aimed to investigate the relationship between pyrolysis temperatures (300 °C, 500 °C and 700 °C) and biochar properties and environmental risks associated with heavy metals (Cu, Zn, Pb, Cd, Ni and Cr) and to discuss possible mechanisms of heavy metal immobilization. The results showed that the biochar pH value increased from 5.87 to 10.50 and the specific area grew from 5.26 m2/g to a maximum of 15.23 m2/g with pyrolysis temperature rose. Pyrolysis enhanced aromatization and increased stability of biochar, and part of oxygen-containing functional groups decomposed. Although heavy metals enriched in pyrolysis, high temperatures promoted the bioavailable fractions converted to more stable ones, and the heavy metals leaching rate was reduced by 5.5% on average. This may be related to the functional group decomposition, pore collapse and wrapping, and the new crystalline phases formation. The environmental risk was significantly reduced (RI value below 51.00), indicating the relatively safe and reliable performance of sludge biochar. The study can provide a theoretical basis for sludge management and the biochar safe use in soil.

17655. 题目: Interactive impacts of climate change and agricultural management on soil organic carbon sequestration potential of cropland in China over the coming decades
文章编号: N22011218
期刊: Science of The Total Environment
作者: Yicheng Wang, Fulu Tao, Yi Chen, Lichang Yin
更新时间: 2022-01-12
摘要: Cropland plays an important role in Soil Organic Carbon (SOC) sequestration. Although the SOC stock and its dynamic in the past decades have been extensively investigated, the information as to where, how much, and how SOC could be potentially sequestered in the coming decades has rarely been available. Here, the Rothamsted Carbon model was applied to investigate the spatiotemporal pattern of SOC sequestration potential for China's cropland in 2021–2040 at 1 km resolution, as well as the interactive impacts of climate change and agricultural management on SOC sequestration. Under the combined impacts of climate change and C input, the SOC sequestration of China's cropland in 2021–2040 would be about 0.56 Mg C ha−1 (0.06% yr−1), 1.33 Mg C ha−1 (0.15% yr−1), 2.10 Mg C ha−1 (0.24% yr−1), and 3.65 Mg C ha−1 (0.41% yr−1), with no increase, 5%, 10%, and 20% increase of C input, respectively. Therefore, a >20% increase in C input would be necessary to realize the promise of the ‘4 per 1000’ initiative. Climate change would decrease SOC sequestration by 26.6–27.6 Tg yr−1 (or 60.4–62.7%). An increase of C input by 0%, 5%, 10%, and 20% relative to business as usual (BAU) would increase SOC sequestration by 4.8 (or 10.8%), 6.6 (or 14.9%), 13.1 (or 29.8%), and 26.2 (or 59.6%) Tg yr−1, respectively. The contributions of temperature, precipitation, and C input to SOC sequestration will be averagely 18.6%, 22.4%, and 59.0%, respectively. Our findings quantify the SOC sequestration in 2021–2040 at a high spatial resolution under the interactive impacts of climate change and agricultural management, which help to identify potential foci and develop region-specific measures to increase SOC sequestration efficiently.

17656. 题目: Impacts of gasification biochar and its particle size on the thermal behavior of organic waste co-composting process
文章编号: N22011217
期刊: Science of The Total Environment
作者: Filippo Ottani, Massimiliano Parenti, Simone Pedrazzi, Giuseppe Moscatelli, Giulio Allesina
更新时间: 2022-01-12
摘要: This work investigates the effects of gasification biochar on the thermal behavior of organic municipal waste composting. Two different biochar granulometries were mixed in a 3% w/w share with the organic fraction of municipal waste and tested in nine (three per thesis and three as control) reactors of 1 m3 of volume, designed to simulate full-scale aerated static piles. The temperatures of each composter were monitored for 31 days of the active composting phase and used as key parameters for air flow tuning. After the active phase was completed, the air was turned off and the temperatures were monitored for an additional 31 days during compost maturation. Results show that biochar-aided composters run 4 °C hotter and are more stable in temperature compared to the control thesis. Experimental data were used as a basis for thermal energy modeling: the addition of fine biochar to composting material increased the thermal energy production by 0.5 MJ kg−1 compared to the control thesis; coarse biochar increased the thermal energy production by 0.4 MJ kg−1. The standard composting process, without biochar, produced 2.5 MJ kg−1. Results might serve as a starting point for further considerations in terms of composting time reduction, improvement of the final product and reduction of process related issues, such as undesired anaerobic decomposition, leachate production and temperature instability.

17657. 题目: Ensuring planetary survival: the centrality of organic carbon in balancing the multifunctional nature of soils
文章编号: N22011216
期刊: Critical Reviews in Environmental Science and Technology
作者: Peter M. Kopittke, Asmeret Asefaw Berhe, Yolima Carrillo, Timothy R. Cavagnaro, Deli Chen, Qing-Lin Chen, Mercedes Román Dobarco, Feike A. Dijkstra, Damien J. Field, Michael J. Grundy, Ji-Zheng He, Frances C. Hoyle, Ingrid Kögel-Knabner, Shu Kee Lam, Petra Marschner, Cristina Martinez, Alex B. McBratney, Eve McDonald-Madden, Neal W. Menzies, Luke M. Mosley, Carsten W. Mueller, Daniel V. Murphy, Uffe N. Nielsen, Anthony G. O’Donnell, Elise Pendall, Jennifer Pett-Ridge, Cornelia Rumpel, Iain M. Young, Budiman Minasny
更新时间: 2022-01-12
摘要: Not only do soils provide 98.7% of the calories consumed by humans, they also provide numerous other functions upon which planetary survivability closely depends. However, our continuously increasing focus on soils for biomass provision (food, fiber, and energy) through intensive agriculture is rapidly degrading soils and diminishing their capacity to deliver other vital functions. These tradeoffs in soil functionality – the increased provision of one function at the expense of other critical planetary functions – are the focus of this review. We examine how land-use change for biomass provision has decreased the ability of soils to regulate the carbon pool and thereby contribute profoundly to climate change, to cycle the nutrients that sustain plant growth and ecosystem health, to protect the soil biodiversity upon which many other functions depend, and to cycle the Earth’s freshwater supplies. We also examine how this decreasing ability of soil to provide these other functions can be halted and reversed. Despite the complexity and the interconnectedness of soil functions, we show that soil organic carbon plays a central role and is a master indicator for soil functioning and that we require a better understanding of the factors controlling the behavior and persistence of C in soils. Given the threats facing humanity and their economies, it is imperative that we recognize that Soil Security is itself an existential challenge and that we need to increase our focus on the multiple functions of soils for long-term human welfare and survivability of the planet.

17658. 题目: Organic amendments combined with biochar for improving soil and plant quality in a Torreya grandis plantation
文章编号: N22011215
期刊: Journal of Soils and Sediments
作者: Zhanhua Zhou, Kim Yrjälä, Junhui Chen, Chenliang Yu, Wenhui Shi, Hua Qin, Weiwu Yu, Wensheng Dai, Yuanyuan Hu, Jiasheng Wu
更新时间: 2022-01-12
摘要: Purpose Biochar and organic amendments can improve soil quality, but their combined effects on plant growth as well as soil microbial functions deserve further investigation. Materials and methods We established an 8-month field experiment to explore the effects of biochar (0, 10 t ha−1), organic amendments (10 t ha−1 sheep manure and 2 t ha−1 rapeseed cake), and their combinations on plant growth and soil quality in a Torreya grandis plantation. Results and discussion Organic amendments significantly (P < 0.05) increased soil available and total P contents as well as mineral nutrients in leaves. Biochar significantly increased soil available P and K and total K contents. Biochar combined with sheep manure rather than rapeseed cake displayed a significant (P < 0.05) increase in plant quality and soil nutrients in comparison with manure or rapeseed cake addition alone. Biochar combined with sheep manure significantly increased microbial activity (indicated by microbial substrate utilization rate) compared with manure alone treatment. In addition, organic amendments in combination with biochar generally had no significant effects on microbial diversity indices, but they had some interactive effects on some bacterial taxa, such as Proteobacteria and Actinobacteria, and predicted metabolism functions. Changes in soil nutrient contents were closely linked with soil bacterial community composition and improvements in plant quality. Conclusions The results showed that 10 t ha−1 biochar co-applied with 10 t ha−1 sheep manure was suitable for the promotion of soil fertility and plant growth in a Torreya grandis plantation.

17659. 题目: Modeled approaches to estimating blue carbon accumulation with mangrove restoration to support a blue carbon accounting method for Australia
文章编号: N22011214
期刊: Limnology and Oceanography
作者: Catherine E. Lovelock, M. Fernanda Adame, Don W. Butler, Jeffrey J. Kelleway, Sabine Dittmann, Benedikt Fest, Karen J. King, Peter I. Macreadie, Katherine Mitchell, Mark Newnham, Anne Ola, Christopher J. Owers, Nina Welti
更新时间: 2022-01-12
摘要: The development and refinement of methods for estimating organic carbon accumulation in biomass and soils during mangrove restoration and rehabilitation can encourage uptake of restoration projects for their ecosystem services, including those of climate change mitigation, or blue carbon. To support the development of a blue carbon method for Australia under the Emission Reduction Fund scheme we investigated; (1) whether carbon accumulation data from natural mangroves could be used to estimate carbon accumulation during restoration; (2) modeling mangrove biomass accumulation; and (3) how modeled carbon accumulation could be achieved over heterogeneous sites. First, we assessed carbon accumulation in soil and biomass pools from the global literature, finding that estimating carbon accumulation using data from natural mangroves provided similar estimates as those for restored or rehabilitated mangroves. We assessed mangrove biomass accumulation from global chronosequence studies, which we used to develop regional models for estimating biomass accumulation with restoration in Australia using values from local natural mangroves. Estimating biomass carbon accumulation using site-based means of stand biomass provided similar estimates as values estimated through use of regional means values stratified by elevation; and reduced overestimates of biomass carbon accumulation that were based on regional mean values. Modeling soil carbon accumulation over environmentally heterogeneous project sites can apply a similar approach, stratifying over variation in site elevation. Our analysis provides a strategy for modeling blue carbon pools for an Australian blue carbon method that accommodates regional differences and is based on data from natural mangroves.

17660. 题目: Land Use Overrides Stream Order and Season in Driving Dissolved Organic Matter Dynamics Throughout the Year in a River Network
文章编号: N22011213
期刊: Environmental Science & Technology
作者: Ashley A. Coble, Adam S. Wymore, Jody D. Potter, William H. McDowell
更新时间: 2022-01-12
摘要: Anthropogenic land use has increased nutrient concentrations and altered dissolved organic matter (DOM) character and its bioavailability. Despite widespread recognition that DOM character and its reactivity can vary temporally, the relative influence of land use and stream order on DOM characteristics is poorly understood across seasons and the entire flow regime. We examined DOM character and 28-day bioavailable dissolved organic carbon (BDOC) across a river network to determine the relative roles of land use and stream order in driving variability in DOM character and bioavailability throughout the year. DOM in 1st-order streams was distinct from higher stream orders with lower DOC concentrations, less aromatic (specific ultraviolet absorbance at 254 nm (SUVA254)), more autochthonous (fluorescence index), and more recently produced (β/α) DOM. Across all months, variability in DOM character was primarily explained by land use, rather than stream order or season. Land use and stream order explained the most DOM variation in transitional and winter months and the least during dry months. BDOC was greater in watersheds with less aromatic (SUVA254) and more recent allochthonous DOM (β/α) and more development and impervious surface. With continued development, the bioavailability of DOM in the smallest and most impacted watersheds is expected to increase.