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Thermal stability of soil organic carbon subjected to water erosion as a function of edaphic factors

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International Journal of Sediment Research 2022年第1期37卷 26-36页

作者： Zhongwu Li Linhui Xiao Chuxiong Deng Zaijian Yuan Chen Liang Qian Xiong Zeting Li Xiaodong Nie College of Resources and Environmental Science Hunan Normal University Guangdong Engineering Center of Non-point Source Pollution Control Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management Guangdong Institute of Eco-environmental Science & Technology Guangdong Academy of Sciences National-Regional Joint Engineering Research Center for soil Pollution Control and Remediation in South China

The stability of soil organic carbon (SOC),as it relates to resistance to decomposition,is important for greenhouse gas emission and climate change.However,the SOC stabilization and its related influencing factors subjected to water erosion remain uncertain.The objective of the current study was to determine the SOC stability under long-term water erosion and to investigate the link between SOC stability and edaphic factors.soil samples from eroded,depositional,and control sites in a closed watershed in subtropical China were collected.The SOC concentration,carbon functional groups,soil physicochemical properties,and thermal stability of SOC were determined.The study results showed that the primary component of the SOC functional groups was O-alkyl carbon (reached 40%),and its proportion has no significant difference among different sites.The TG-T50(the temperature at which 50%of the soil organic matter is lost) values indicated that the SOC thermal stability in the eroded topsoil was higher than that of the deposited topsoil.The carbon functional groups were lack of relation with SOC thermal stability(p>0.05).However,the TG-T50was significantly positively correlated with the cation exchange capacity and silt,but remarkably negatively correlated with SOC,dissolved organic carbon,total nitrogen,sand,clay,p H,aluminum,specific surface area,and iron oxides.These results indicated that the edaphic factors,which were strongly affected by micro-environment,are the main factors affecting thermal stability of organic carbon.The SOC stabilization under the effects of long-term water erosion should be addressed from the perspective of the ecosystem.

关键词： soil erosion soil organic matter Thermogravimetry Preservation Stability

Sorption and desorption of sex hormones in soil-and sediment-water systems:A review

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soil Ecology Letters 2022年第1期4卷 1-17页

作者： Xiong Dai Xingjian Yang Bihai Xie Jiajia Jiao Xiuping Jiang Chengyu Chen Zhen Zhang Zhili He Hang Lin Weisong Chen Yongtao Li College of Natural Resources and Environment Joint Institute for Environment&EducationSouth China Agricultural UniversityGuangzhou 510642China Key Laboratory of Southern Farmland Pollution Prevention and Control Ministry of Agriculture and Rural AffairsHunan Division of GRG Metrology and TestChangsha 410000China Dongguan Institute of Food Crops and Flowers Dongguan 523063China

Sex hormones are a group of potent endocrine disruptors that can be released into agricultural soils and sediment via wastewater discharge and manure fertilization.Sorption represents a critical determinant for the transport potential and risks of sex hormones in the environment.Therefore,this study reviewed the sorption and desorption mechanisms of sex hormones in soil-and sedimentwater systems,and summarized the effects of various factors on sorption and desorption processes.A total of 359 set of sorption data were collected from the literature.Sex hormones were mostly described by the linear model.The sorption magnitudes(logKoc)of estrogens,androgens,and progestins were in the range of 2.77–3.90,2.55–4.18,and 2.61–4.39,respectively.The average logKoc values of the sex hormones were significantly correlated with their logKow values(R^(2)=0.13,psoils and sediment(R^(2)=0.16–0.99,psoil-and sediment-water systems.The sorption of sex hormones in soil-and sediment-water systems can also be affected by other environmental variables,including pH,temperature,and ionic strength.Future studies should focus on the coupled leaching-sorption processes in manure-water-soil systems under field-scale conditions.

关键词： Endocrine disruption Environmental variable soil organic matter Mineral Desorption hysteresis

soil C, N and P stocks and stoichiometry under different vegetation on the surface of the Leshan Giant Buddha

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soil Ecology Letters 2022年第1期4卷 57-68页

作者： Fujia Wu Wanqin Yang Bo Sun Tianyu Yang Xuli Chen Zhenfeng Xu Huixing Song College of Landscape Architecture Sichuan Agricultural UniversityChengdu 611130China College of Life Science Taizhou UniversityTaizhou 318000China Northwest Research Institute Co. Ltdof China Railway Engineering CorporationLanzhou 730000China Grottoes Research Center Management Committee of Leshan Grand Buddha Scenic SpotLeshan 614003China Provincial Key Laboratory of Ecological Forestry Engineering Institute of Ecology and ForestrySichuan Agricultural UniversityChengdu 611130China

The accumulation of soil organic matter and nutrients is an important pathway in effectivelyunderstanding the mechanisms of plant settlement and rock weathering, while the characteristics ofsoil organic carbon (C), nitrogen (N) and phosphorus (P) under different vegetation remain unclear.In this study, the stocks and stoichiometry of soil organic C, N and P were determined in differentpositions and types of vegetation on the surface of the Leshan Giant Buddha. We found that the totalstocks of soil organic C, N and P were 1689.77, 134.6 and 29.48 kg, respectively, for the Buddha.The stocks of soil organic C, N and P under vascular plants were higher than those under othervegetation, with highest values observed under herb. Higher stocks per unit area (m2) of soil organicC, N and P were found on the left and right arms, shoulders, and two platforms. These results providea full primary picture in understanding soil organic C, N and P accumulation and distribution on thesurface of the Buddha, which could supply the fundamental data on weathering management of theBuddha and other similar open-air stone carvings.

关键词： Rock weathering soil organic matter Plant settlement Open-air stone carving

Responses of Wheat Production, Quality, and soil Profile Properties to Biochar Applied at Different Seasons in a Rice-Wheat Rotation

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Phyton-International Journal of Experimental Botany 2023年第12期92卷 3359-3370页

作者： Lipei Chen Rilie Deng Xuewen Li Min Yu Hongdong Xiao Department of Horticulture Foshan UniversityFoshan528000China

In the rice-wheat rotation system,biochar(BC)can be applied at the initiation of the rice or wheat season.Here,we compared the effects of BC that were applied at two different crop seasons on wheat production,quality,and soil profile properties in a rice-wheat rotation system with nitrogen(N)fertilizer applied at 280 kg/ha rate.Results showed that both wheat grain production and N recovery use efficiency were influenced by BC applied at two crop seasons.Biochar application did not affect the total non-essential amino-acid,but when applied during wheat season,BC significantly(psoil at 0–6 cm and 20–30 cm by 0.14–0.18 and 0.05–0.08 units,respectively.The NH4+-N content of the whole observed soil profile were reduced by BC application,however,the effect of BC on NO3–-N content varied with the application season and profile depth.Interestingly,BC applied at wheat and rice season significantly(psoil N contents by 48.4%and 19.7%,respectively.In addition,data suggested that BC applied during wheat season performed better in enhancing soil available phosphorus,potassium,and organic matter contents.In conclusion,we suggest that the optimum application time of BC for enhancing crop production and quality(take amino-acid content for example)and improving soil fertility is at the initiation of the wheat season.

关键词： Amino-acid biochar paddy soil rice-wheat rotation soil fertility soil organic matter

Variation characteristics of CO_(2) in a newly-excavated soil profile,Chinese Loess Plateau:Excavation-induced ancient soil organic carbon decomposition

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Journal of Groundwater Science and Engineering 2022年第1期10卷 19-32页

作者： Chao Song Man Liu Qiu-yao Dong Lin Zhang Pan Wang Hong-yun Chen Rong Ma Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China Key Laboratory of Quaternary Chronology and Hydro-Environmental Evolution China Geological SurveyShijiazhuang 050061China Institute of Earth Sciences China University of Geosciences(Beijing)Beijing 100083China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing 210029China

soils of the Chinese Loess Plateau(CLP)contain substantial amounts of soil inorganic carbon(SIC),as well as recent and ancient soil organic carbon(SOC).With the advent of the Anthropocene,human perturbation,including excavation,has increased soil CO_(2) emission from the huge loess carbon pool.This study aims to determine the potential of loess CO_(2) emission induced by excavation.soil CO_(2) were continuously monitored for seven years on a newly-excavated profile in the central CLP and the stable C isotope compositions of soil CO_(2) and SOC were used to identify their sources.The results showed that the soil CO_(2) concentrations ranged from 830μL·L^(-1) to 11190μL·L^(-1) with an annually reducing trend after excavation,indicating that the human excavation can induce CO_(2) production in loess profile.Theδ^(13) C of CO_(2) ranged from–21.27‰to–19.22‰(mean:–20.11‰),with positive deviation from top to bottom.The range of δ^(13)CSOC was–24.0‰to–21.1‰with an average of–23.1‰.Theδ^(13) C-CO_(2) in this study has a positive relationship with the reversed CO_(2) concentration,and it is calculated that 80.22%of the soil CO_(2) in this profile is from the microbial decomposition of SOC and 19.78%from the degasification during carbonate precipitation.We conclude that the human excavation can significantly enhance the decomposition of the ancient OC in loess during the first two years after perturbation,producing and releasing soil CO_(2) to atmosphere.

关键词： soil organic matter Human excavation soil CO_(2) Stable carbon isotopic composition China Loess Plateau

soil health and root-zone enrichment characteristics between paired grassland and cropland fields in the southeastern United States

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Grassland Research 2023年第4期2卷 299-308页

作者： Alan J.Franzluebbers Stephan van Vliet Sierra Young Matt H.Poore USDA-Agricultural Research Service RaleighNorth CarolinaUSA Department of Nutrition Dietetics&Food SciencesUtah State UniversityLoganUtahUSA Civil and Environmental Engineering Department Utah State UniversityLoganUtahUSA Department of Animal Science North Carolina State UniversityRaleighNorth CarolinaUSA

Background:soil organic C and N data from privately managed pastures in the southeastern United States are relatively scant.Methods:A paired-farm approach was deployed to determine how a variety of soil health parameters related to nutrient and water cycling might be altered under grazed,botanically diverse perennial pastures compared with annual monoculture croplands in three Major Land Resource Areas of the southeastern United States.Results:soil stability index averaged 0.64 and 0.91mm mm^(-1) under cropland and grazed pasture,respectively,suggesting that pastures had a more stable soil surface that was resistant to erosion and allowed rapid water infiltration.Surface-soil organic C and N fractions(i.e.,total,particulate,and mineralizable fractions at 0-10 cm depth)were greater under pasture than under cropland.Across locations,root-zone enrichments(0-30 cm depth)of organic C and N fractions were greater under pasture than under cropland.Within locations,root-zone enrichment of total soil N was greater(psoil organic C and N and improve soil surface stability conditions compared with neighboring croplands producing commodity feed grains for feedlot finishing.

关键词： land use soil aggregation soil health soil organic matter

soil organic carbon stocks and belowground biomass in patches in heterogeneous grassland

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Grassland Research 2023年第4期2卷 279-288页

作者： Martin Komainda Eliana Mohn Klára Kajzrová Kilian Obermeyer Jan Titěra Vilém Pavlů Johannes Isselstein Department of Crop Sciences Grassland ScienceGeorg-August-UniversityGöttingenGermany Faculty of Science Humanities and EducationTechnical University of LiberecLiberecCzechia Department of Agroecology and Crop Production Faculty of AgrobiologyFood and Natural ResourcesCzech University of Life SciencesPrahaCzechia University of Vechta VechtaGermany Grassland Research Station Liberec Department of Weeds and Vegetation of AgroecosystemsCrop Research InstitutePrahaCzechia Centre of Biodiversity and Sustainable Land Use GöttingenGermany

Background:Selective grazing creates stable patches of contrasting sward height,thereby providing different growth conditions for the grass sward above and below ground and potentially affecting soil organic carbon(SOC)stocks.We hypothesized that the presence of patches leads to greater spatial variability in belowground biomass(BGB)and SOC stocks than occurs between pastures managed under different stocking intensities.Methods:A long-term grazing experiment consisting of three stocking intensities was used for this study.We studied BGB,SOC,and soil total nitrogen(Ntot)stocks in the 0-15 cm soil depth.Shannon diversity of plant species,soil bulk density,soil phosphorus,potassium,and magnesium contents were considered.Results:There were no significant effects of patch or stocking intensity on BGB,SOC,and Ntot stocks.Short patches had a greater Shannon diversity than tall patches(psoil correlated positively with sward height(psoil nutrient contents in short-patch areas and higher nutrient contents together with light competition in tall-patch areas might balance each other out with respect to BGB and SOC stocks.

关键词： grazing land roots seminatural grassland soil organic matter stocking rate

Simulation of Random Dynamic Changes of soil organic matter Based on Fuzzy Markov Chain Model

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Simulation of Random Dynamic Changes of Soil Organic Matter ...

Changes in particulate and mineral-associated organic carbon with land use in contrasting soils

2010 Chinese Control and Decision Conference

作者： Panpan Gao~1,Zhihong Qie~(1*),Xiangbin Kong~(2*) 1.College of Urban and Rural Construction,Agricultural University of Hebei,Baoding 071001,China 2.College of Resources and Environmental Science,China Agricultural University,Beijing 100094,China

＜正＞In response to the random change features of soil organic matter content and limited monitoring data in practice,a fuzzy Markov chain model is put forward in this paper to be used in simulating and forecasting the dynamic change of the region soil organic matter content.Firstly,the content of organic matter is divided into four levels by using grey clustering method in order to establish the grading model and fuzzy membership function of the sample classification which can make the change of organic matter state more smooth,continuous and reasonable;Secondly, in view of the limited monitoring data of soil nutrient,Marko transition matrix is simplified,and a new method based on Hybrid Particle Swarm Optimization（HPSO） is proposed to optimize the transition matrix;Finally,taking a county in Hebei province as the sample area,the simulation and forecast of dynamic change of soil organic matter are achieved.Analysis result shows that the simulation result suits well with the practical change trend.

关键词： soil organic matter Markov chain model grey clustering analysis and Hybrid Particle Swarm Optimization

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Pedosphere 2023年第3期33卷 421-435页

作者： Sabina YEASMIN Balwant SINGH Cliff T.JOHNSTON Quan HUA Donald L.SPARKS Sydney Institute of Agriculture School of Life and Environmental SciencesThe University of SydneySydney NSW 2006(Australia) Department of Agronomy Bangladesh Agricultural UniversityMymensingh-2202(Bangladesh) Crop Soil and Environmental SciencesPurdue UniversityWest Lafayette IN 47907(USA) Australian Nuclear Science and Technology Organisation Locked Bag 2001Kirrawee DC NSW 2232(Australia) Department of Plant and soil Sciences University of DelawareNewark DE 19716(USA)

soil organic carbon(SOC)is the largest terrestrial carbon(C)stock,and the capacity of soils to preserve organic C(OC)varies with many factors,including land use,soil type,and soil depth.We investigated the effect of land use change on soil particulate organic matter(POM)and mineral-associated organic matter(MOM).Surface(0–10 cm)and subsurface(60–70 cm)samples were collected from paired sites(native and cropped)of four contrasting soils.Bulk soils were separated into POM and MOM fractions,which were analyzed for mineralogy,OC,nitrogen,isotopic signatures,and14C.The POM fractions of surface soils were relatively unaffected by land use change,possibly because of the continuous input of crop residues,whereas the POM fractions in corresponding subsurface soils lost more OC.In surface soils,MOM fractions dominated by the oxides of iron and aluminum(oxide-OM)lost more OC than those dominated by phyllosilicates and quartz,which was attributed to diverse organic matter(OM)input and the extent of OC saturation limit of soils.In contrast,oxide-OM fractions were less affected than the other two MOM fractions in the subsurface soils,possibly due to OC protection via organo-mineral associations.The deviations in isotopic signature(linked with vegetation)across the fractions suggested that fresh crop residues constituted the bulk of OM in surface soils(supported by greater14C).Increased isotopic signatures and lower14C in subsurface MOM fractions suggested the association of more microbially processed,aged OC with oxide-OM fractions than with the other MOM fractions.The results reveal that the quantity and quality of OC after land use change is influenced by the nature of C input in surface soils and by mineral-organic association in subsurface soils.

关键词： land use change microbial decomposition organic carbon saturation organo-mineral association soil organic matter