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Contributions of Different N Sources to Crop N Nutrition in a Chinese Rice Field

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Pedosphere 2010年第2期20卷 198-208页

作者： CHEN Yi,TANG Xu,YANG Sheng-Mao,WU Chun-Yan and WANG Jia-Yu institute of environmental resources and soil fertilizer,Zhejiang Academy of Agricultural Sciences,Hangzhou 310021 (China) institute of environmental resources and soil fertilizer Zhejiang Academy of Agricultural Sciences Hangzhou 310021 (China)

N availability is one of the most important factors limiting crop yield *** recovery of applications of 15 N-labeled fertilizer and crop residues in a rice-wheat cropping system was determined for up to 6 consecutive growing *** crop residues from the previous season were either incorporated or removed as two different *** results showed that 16.55%-17.79% (17.17% on average) of the fertilizer N was recovered in the crop during the first growing season,suggesting that more than 80% of crop N was not directly from the N *** 15 N-labeled residues were applied,12.01% was recovered in the crop in the first growing *** average recoveries of fertilizer N and crop residue N in the soil after the first growing season were 33.46% and 85.64%,respectively.N from soil organic matter contributed approximately 83% of the N in the crop when 15 N fertilizer was applied or 88% when crop residues were *** was a larger difference in the total 15 N recovery in plant and soil between N applications in the forms of fertilizer and crop *** of crop residues following the 15 N fertilizer application did not significantly promote 15 N recovery in the crop or *** average,only additional 1.94% of N for the fertilizer-applied field or 5.97% of N for the crop residue-applied field was recovered by the crops during the 2nd and 3rd growing *** total recoveries of 15 N in crop and soil were approximately 64.38% for the fertilizer-applied field after 6 growing seasons and 79.11% for the crop residue-applied field after 5 growing *** fertilizer N appeared to be more readily available to crops than crop residue N,crop residue N replenished soil N pool,especially N from soil organic matter,much more than fertilizer ***,crop residue N was a better source for sustaining soil organic *** results suggested that the long-term effect of fertilizer or crop residues on N recovery were differen

关键词： crop residue 15 N recovery N fertilizer

Information extraction and dynamic evaluation of soil salinization with a remote sensing method in a typical county on the Huang-Huai-Hai Plain of China

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Pedosphere 2020年第4期30卷 496-507页

作者： Xiaoguang ZHANG Biao HUANG Feng LIU State Key Laboratory of soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) Key Laboratory of soil environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) College of resource and environment Qingdao Agricultural UniversityQingdao 266109(China)

Monitoring the dynamics of soil salinization is of great importance for agricultural *** study selected Yucheng County,a typical county on the Huang-Huai-Hai Plain(HHHP)of China,as the study area and evaluated the spatial and temporal variation of soil *** methods,consisting of principal component analysis(PCA)transformation,tasseled cap(TC)transformation,and optimal band combination(OBC),were used to extract information from an early Landsat multispectral scanner(MSS)image from 1984,and their advantages were *** addition,OBC was used on a thematic mapper(TM)image from *** iteratively self-organizing data analysis algorithm was used together with prior knowledge of likely classifications to interpret the MSS and TM images for data ***,a transfer matrix method was used to assess the spatial and temporal variability of soil salinization and analyze the driving factors of soil *** to PCA transformation and OBC,TC transformation was a more effective method for extracting soil salinization information from the MSS *** results indicate that a soil area of approximately 298 km^2was affected by salinity in 1984 in Yucheng County,of which 5.40%,11.96%,and 12.75%were classified as being subject to slight,moderate,and severe salinization,*** 2009,the saline area was reduced to only 146 km^2,of which 10.70%and 3.75%were characterized by slight to moderate salinization and no severe salinization,*** saline land decreased at an average rate of 6 km^2per *** decrease was probably a result of lower groundwater depth,increased organic fertilizer or crop straw in soil,changed land use type,and increased vegetation coverage.

关键词： Landsat multispectral scanner optimal band combination principal component analysis soil salinity tasseled cap thematic mapper

Manure substitution improves maize yield by promoting soil fertility and mediating the microbial community in lime concretion black soil

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Journal of Integrative Agriculture 2024年第2期23卷 698-710页

作者： Minghui Cao Yan Duan Minghao Li Caiguo Tang Wenjie Kan Jiangye Li Huilan Zhang Wenling Zhong Lifang Wu The Center for Ion Beam Bioengineering&Green Agriculture Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Zhongke Taihe Experimental Station Taihe 236626China institute of resources and environment Jiangsu Academy of Agricultural SciencesNanjing 210014China

Synthetic nitrogen(N)fertilizer has made a great contribution to the improvement of soil fertility and productivity,but excessive application of synthetic N fertilizer may cause agroecosystem risks,such as soil acidification,groundwater contamination and biodiversity ***,organic substitution has received increasing attention for its ecologically and environmentally friendly and productivity ***,the linkages between manure substitution,crop yield and the underlying microbial mechanisms remain *** bridge this gap,a three-year field experiment was conducted with five fertilization regimes:i)Control,non-fertilization;CF,conventional synthetic fertilizer application;CF_(1/2)M_(1/2),1/2 N input via synthetic fertilizer and 1/2 N input via manure;CF_(1/4)M_(3/4),1/4 N input synthetic fertilizer and 3/4 N input via manure;M,manure *** fertilization treatments were designed to have equal N *** results showed that all manure substituted treatments achieved high soil fertility indexes(SFI)and productivities by increasing the soil organic carbon(SOC),total N(TN)and available phosphorus(AP)concentrations,and by altering the bacterial community diversity and composition compared with ***,AP,and the soil C:N ratio were mainly responsible for microbial community *** co-occurrence network revealed that SOC and AP had strong positive associations with Rhodospirillales and Burkholderiales,while TN and C:N ratio had positive and negative associations with Micromonosporaceae,*** specific taxa are implicated in soil macroelement *** Forest analysis predicted that both biotic(bacterial composition and Micromonosporaceae)and abiotic(AP,SOC,SFI,and TN)factors had significant effects on crop *** present work strengthens our understanding of the effects of manure substitution on crop yield and provides theoretical support for optimizing fertilization strategies.

关键词： fertilization manure substitution soil fertility maize yield bacterial community

Improving model performance in mapping cropland soil organic matter using time-series remote sensing data

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Journal of Integrative Agriculture 2024年第8期23卷 2820-2841页

作者： Xianglin Zhang Jie Xue Songchao Chen Zhiqing Zhuo Zheng Wang Xueyao Chen Yi Xiao Zhou Shi institute of Applied Remote Sensing and Information Technology College of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China Department of Land Management Zhejiang UniversityHangzhou 310058China ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311215China institute of Digital Agriculture Zhejiang Academy of Agricultural SciencesHangzhou 310021China Key Laboratory of Spectroscopy Sensing Ministry of Agriculture and Rural AffairsHangzhou 310058China

Faced with increasing global soil degradation,spatially explicit data on cropland soil organic matter(SOM)provides crucial data for soil carbon pool accounting,cropland quality assessment and the formulation of effective management *** a spatial information prediction technique,digital soil mapping(DSM)has been widely used to spatially map soil information at different ***,the accuracy of digital SOM maps for cropland is typically lower than for other land cover types due to the inherent difficulty in precisely quantifying human *** overcome this limitation,this study systematically assessed a framework of“information extractionfeature selection-model averaging”for improving model performance in mapping cropland SOM using 462 cropland soil samples collected in Guangzhou,China in *** results showed that using the framework of dynamic information extraction,feature selection and model averaging could efficiently improve the accuracy of the final predictions(R^(2):0.48 to 0.53)without having obviously negative impacts on *** the dynamic information of the environment was an efficient way to generate covariates that are linearly and nonlinearly related to SOM,which improved the R^(2)of random forest from 0.44 to 0.48 and the R^(2)of extreme gradient boosting from 0.37to *** recursive feature selection(FRFS)is recommended when there are relatively few environmental covariates(environmental covariates(>500).The Granger-Ramanathan model averaging approach could improve the prediction accuracy and average *** the structures of initial prediction models are similar,increasing in the number of averaging models did not have significantly positive effects on the final *** the advantages of these selected strategies over information extraction,feature selection and model averaging have a great potential for high-accuracy soil mapping

关键词： cropland soil organic matter digital soil mapping machine learning feature selection model averaging

COMPARATIVE STUDY ON RESIDUAL EFFECTS OF ORGANIC AND INORGANIC fertilizer NITROGEN IN WATERLOGGED soil AND DRYLAND soil

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Science China Chemistry 1983年第2期26卷 167-173页

作者：黄东迈朱培立高家骅 Jiangsu Academy of Agricultural Sciences Nanjing institute of soil and fertilizer

The balance of residual fertilizer nitrogen was studied with the application of crotalariaand ammonium sulfate in two opposite cropping sequences —rice-wheat-rice-wheat and wheatrice-wheat-rice. Air-dried plant of crotalaria tagged with(NH)SOand containing 6.5% ofN in total nitrogen was used as the sources ofN labelled organic manure. Ammonium sulfate tagged with 10.6%N was applied as inorganic *** recovery rate of residual fertilizer N was very low, averaging only 2.5%+2% on the basis of applied fertilizer N, in the case of rice as well as wheat in each successive cropping season. After the harvest of the first crop, more fertilizer nitrogen was immobilized as residual form in dryland soil than in waterlogged soil. The percentage of cumulative uptake of fertilizer N in rice-wheat-rice-wheat cropping sequence was much greater than that in the wheat-rice-wheat-rice sequence. It might be more economical to apply this kind of manure as basal dressing first to rice.

关键词： COMPARATIVE STUDY ON RESIDUAL EFFECTS OF ORGANIC AND INORGANIC fertilizer NITROGEN IN WATERLOGGED soil AND DRYLAND soil

Effects of rape straw and red mud on extractability and bioavailability of cadmium in a calcareous soil

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Frontiers of environmental Science & Engineering 2015年第3期9卷 419-428页

作者： Junxing YANG Liqun WANG Jumei LI Dongpu WEI Shibao CHEN Qingjun GUO Yibing MA Centre for environmental Remediation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China National soil Fertility and fertilizer Effects Long-term Monitoring Network Institute of Agrieulttnal Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 China The Key Laboratory of resource environment and GIS College of Resource Environment and Tourism Capital Normal University Beijing 100037 China

Screening of cost-effective soil amendments is important to develop ＂in situ＂ remediation techniques for cadmium （Cd） contaminated soils. In this study, different soil amendments, including red mud, a by-product of the alumina industry, and acid-treated, nano-treated by nanoparticle milling, nano and acid-treated red muds, zeolite, corn straw, and rape straw, were evaluated to immobilize Cd in two added levels （2 and 5 mg Cd·kg^-1 soil） in a calcareous soil by single and sequential extractions and by cucumber （Cucumis sativus L.） pot experiments. Results indicated that cruciferous rape straw significantly decreased the concentrations of water soluble, extractable Cd in soils, and Cd in cucumber plants, and it was more effective than gramineous corn straw. Also, red mud generally decreased the extractability and bioavailability of Cd added to calcareous soils more effectively than zeolite. Furthermore, the efficiency of red mud could be increased by the treatment of nano-particle milling due to the increase in specific surface area of red mud. It is potential to use rape straw and red mud as soil amendments to develop a cost-effective and efficient ＂in situ＂ rernediation technology for Cd mildly contaminated calcareous soils.

关键词： red mud rape straw cadmium immobilization calcareous soil

Failure behavior and strength model of blocky rock mass with and without rockbolts

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International Journal of Mining Science and Technology 2024年第6期34卷 747-762页

作者： Chun Zhu Xiansen Xing Manchao He Zhicheng Tang Feng Xiong Zuyang Ye Chaoshui Xu School of Earth Sciences and Engineering Hohai UniversityNanjing 210024China Key Laboratory of Water Management and Water Security for Yellow River Basin Ministry of Water Resources(under construction)Zhengzhou 450003China State Key Laboratory for Geomechanics&Deep Underground Engineering China University of Mining and TechnologyBeijing 10083China Faculty of Engineering China University of GeosciencesWuhan 430074China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China School of resource and environmental Engineering Wuhan University of Science and TechnologyWuhan 430081China School of Chemical Engineering Faculty of SciencesEngineering and TechnologyThe University of AdelaideAdeliade 5005Australia

To better understand the failure behaviours and strength of bolt-reinforced blocky rocks,large scale extensive laboratory experiments are carried out on blocky rock-like specimens with and without rockbolt *** results show that both shear failure and tensile failure along joint surfaces are observed but the shear failure is a main controlling factor for the peak strength of the rock mass with and without *** rockbolts are necked and shear deformation simultaneously happens in bolt reinforced rock *** the joint dip angle increases,the joint shear failure becomes more *** number of rockbolts has a significant impact on the peak strain and uniaxial compressive strength(UCS),but little influence on the deformation modulus of the rock *** the Winkler beam model to represent the rockbolt behaviours,an analytical model for the prediction of the strength of boltreinforced blocky rocks is *** agreement between the UCS values predicted by proposed model and obtained from experiments suggest an encouraging performance of the proposed *** addition,the performance of the proposed model is further assessed using published results in the literature,indicating the proposed model can be used effectively in the prediction of UCS of bolt-reinforced blocky rocks.

关键词： Blocky rock mass Rockbolt ground support Uniaxial compression test Failure mechanism Uniaxial compressive strength model

Predicting impact forces on pipelines from deep-sea fluidized slides:A comprehensive review of key factors

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International Journal of Mining Science and Technology 2024年第2期34卷 211-225页

作者： Xingsen Guo Ning Fan Defeng Zheng Cuiwei Fu Hao Wu Yanjun Zhang Xiaolong Song Tingkai Nian State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China Department of Civil Environmentaland Geomatic EngineeringUniversity College LondonLondon WC1E 6BTUnited Kingdom Shandong Provincial Key Laboratory of Marine environment and Geological Engineering Ocean University of ChinaQingdao 266100China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China College of Civil Engineering and Architecture Wenzhou UniversityWenzhou 325035China Key Laboratory of Engineering and Technology for Soft soil Foundation and Tideland Reclamation of Zhejiang Province Wenzhou 325035China Zhejiang International Science and Technology Cooperation Base of Ultra-soft soil Engineering and Smart Monitoring Wenzhou 325035China School of Geography Liaoning Normal UniversityDalian 116029China China Railway First Survey and Design institute Group Co. Ltd.Xi’an 710043China Department of Geotechnical Engineering Nanjing Hydraulic Research InstituteNanjing 210024China Wuhan Center China Geological Survey(Central South China Innovation Center for Geosciences)Wuhan 430205China State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines Anhui University of Science and TechnologyHuainan 232001China

Deep-sea pipelines play a pivotal role in seabed mineral resource development,global energy and resource supply provision,network communication,and environmental ***,the placement of these pipelines on the seabed surface exposes them to potential risks arising from the complex deep-sea hydrodynamic and geological environment,particularly submarine *** incidents have highlighted the substantial damage to pipelines due to ***,deep-sea fluidized slides(in a debris/mud flow or turbidity current physical state),characterized by high speed,pose a significant *** assessing the impact forces exerted on pipelines by fluidized submarine slides is crucial for ensuring pipeline *** study aimed to provide a comprehensive overview of recent advancements in understanding pipeline impact forces caused by fluidized deep-sea slides,thereby identifying key factors and corresponding mechanisms that influence pipeline impact *** factors include the velocity,density,and shear behavior of deep-sea fluidized slides,as well as the geometry,stiffness,self-weight,and mechanical model of ***,the interface contact conditions and spatial relations were examined within the context of deep-sea slides and their interactions with *** upon a thorough review of these achievements,future directions were proposed for assessing and characterizing the key factors affecting slide impact loading on pipelines.A comprehensive understanding of these results is essential for the sustainable development of deep-sea pipeline projects associated with seabed resource development and the implementation of disaster prevention measures.

关键词： Deep-sea fluidized slides Pipes Impact forces Shear behavior of slides Interface contact conditions Spatial relation

Dynamic Relationship Between Biologically Active soil Organic Carbon and Aggregate Stability in Long-Term Organically Fertilized soils

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Pedosphere 2012年第5期22卷 616-622页

作者： LI Cheng-Liang XU Jiang-Bing HE Yuan-Qiu LIU Yan-Li FAN Jian-Bo College of resources and environment Shandong Agricultural UniversityTai'an 271018(China) institute of soil Science Chinese Academy of SciencesNanjing 210008(China) National Engineering Laboratory for Efficient Utilization of soil and fertilizer resources Tai'an 271018(China)

Biologically active soil organic carbon （BASOC） is an important fraction of soil organic carbon （SOC）, but our understanding of the correlation between BASOC and soil aggregate stability is limited. At an ecological experimental station （28° 04＇-28° 37＇ N, 116° 41＇-117° 09＇ E） in Yujiang County, Jiangxi Province, China, we analyzed the dynamic relationship between soil aggregate stability and BASOC content over time in the red soil （Udic Ferrosols） fertilized with a nitrogen-phosphorus-potassium chemical fertilizer （NPK） without manure or with NPK plus livestock manure or green manure. The dynamics of BASOC was evaluated using CO2 efflux, and soil aggregates were separated according to size using a wet-sieving technique. The soils fertilized with NPK plus livestock manure had a significantly higher content of BASOC and an improved aggregate stability compared to the soils fertilized with NPK plus green manure or NPK alone. The BASOC contents in all fertilized soils decreased over time. The contents of large aggregates （800-2 000 μm） dramatically decreased over the first 7 d of incubation, but the contents of small aggregates （〈 800 μm） either remained the same or increased, depending on the incubation time and specific aggregate sizes. The aggregate stability did not differ significantly at the beginning and end of incubation, but the lowest stability in all fertilized soils occurred in the middle of the incubation, which implied that the soils had a strong resilience for aggregate stability. The change in BASOC content was only correlated with aggregate stability during the first 27 d of incubation.

关键词： aggregate size CO2 release manure mean weight diameter organic fertilization