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Can soil organic carbon sequestration and the carbon management index be improved by changing the film mulching methods in the semiarid region?

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Journal of Integrative Agriculture 2024年第5期23卷 1541-1556页

作者： Jialin Yang Liangqi Ren Nanhai Zhang enke liu Shikun Sun Xiaolong Ren Zhikuan Jia Ting Wei Peng Zhang College of Agronomy Northwest A&F UniversityYangling 712100China Key Laboratory of Crop Physi-Ecology and Tillage Science in Northwestern Loess Plateau Ministry of Agriculture and Rural AfairsNorthwest A&FUniversityYangling 712100China Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081China College of Water Resources and Architectural Engineering Northwest A&F UniversityYangling 712100China

Plastic film mulching has been widely used to increase maize yield in the semiarid area of ***, whether long-term plastic film mulching is conducive to agricultural sustainability in this region remains controversial.A field experiment was initiated in 2013 with five different film mulching methods:(i) control method, flat planting without mulching (CK),(ii) flat planting with half film mulching (P),(iii) film mulching on ridges and planting in narrow furrows(S),(iv) full film mulching on double ridges (D), and (v) film mulching on ridges and planting in wide furrows (R).The effects on soil organic carbon (SOC) content, storage, and fractions, and on the carbon management index (CMI)were evaluated after nine consecutive years of plastic film *** results showed that long-term plastic film mulching generally maintained the initial SOC *** with no mulching, plastic film mulching increased the average crop yield, biomass yield, and root biomass by 48.38, 35.06, and 37.32%, respectively, which led to the improvement of SOC ***, plastic film mulching significantly improved CMI, and increased the SOC content by 13.59%, SOC storage by 7.47%and easily oxidizable organic carbon (EOC) by 13.78%on average,but it reduced the other labile *** sequestration and CMI were improved by refining the plastic film mulching *** S treatment had the best effect among the four mulching methods, so it can be used as a reasonable film mulching method for sustainable agricultural development in the semiarid area.

关键词： plastic film mulching soil organic carbon labile organic carbon fractions semiarid area

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Electronic transport evolution across the successive structural transitions in Ni_(50-x)Fe_xTi_(50) shape memory alloys

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Chinese Physics B 2024年第7期33卷 529-536页

作者：何萍杨金颖任秋飒王彬彬吴光恒刘恩克 Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Materials Science and Engineering University of Science and Technology of BeijingBeijing 100083China

TiNi-based shape memory alloys have been extensively investigated due to their significant applications,but a comprehensive understanding of the evolution of electronic structure and electrical transport in a system with martensitic transformations(MT) is still *** this work,we focused on the electronic transport behavior of three phases in Ni_(50-x)Fe_xTi_(50)across the MT.A phase diagram of Ni_(50-x)Fe_xTi_(50) was established based on x-ray diffraction,calorimetric,magnetic,and electrical *** reveal the driving force of MT,phonon softening was revealed using first-principles ***,the transverse and longitudinal transport behavior changed significantly across the phase transition,which can be attributed to the reconstruction of electronic *** work promotes the understanding of phase transitions and demonstrates the sensitivity of electron transport to phase transition.

关键词： martensitic transformation electronic behavior transport properties first-principles calculations

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气候变化背景下汾渭平原参考作物蒸散量的时空变化与归因分析

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应用生态学报 2024年第6期35卷 1625-1634页

作者：郭大辛李傲翔刘恩科王娟玲山西农业大学山西有机旱作农业研究院太原030031 农业农村部有机旱作农业重点实验室(部省共建) 太原030031 山西农业大学农学院山西晋中030801

参考作物蒸散量(ET_(0))是估算植被生态需水量的关键数据。气候变化背景下,不同区域的ET_(0)变化趋势各有不同,从区域尺度研究ET_(0)的时空变化与归因分析更有利于变化环境下区域的农业用水管理和生态需水量估算。本研究基于第六次国际... 详细信息

参考作物蒸散量(ET_(0))是估算植被生态需水量的关键数据。气候变化背景下,不同区域的ET_(0)变化趋势各有不同,从区域尺度研究ET_(0)的时空变化与归因分析更有利于变化环境下区域的农业用水管理和生态需水量估算。本研究基于第六次国际耦合模式比较项目(CMIP6)发布的最新气候数据和高精度栅格数据,分析了汾渭平原年均ET_(0)在历史时期(1985—2015年)和未来时期(2030—2060年)的变化趋势、空间分布以及气象要素对ET_(0)变化的贡献。结果表明:CMIP6的气象数据经偏差校正后可用于预测ET_(0),且多模式集合方法的预测精度(R^(2)为82.9%,均方根误差为14.9 mm)高于单个气候模式的精度。汾渭平原ET_(0)在历史时期呈显著下降趋势;在未来时期的SSP245和SSP585情景下分别呈不显著上升和显著上升趋势。饱和水汽压差在历史和未来时期对ET_(0)变化的贡献率均最大,是气候变化条件下影响汾渭平原ET_(0)变化的首要气象要素,太阳净辐射和风速是历史时期影响ET_(0)变化的重要气象要素,温度和风速是未来时期影响ET_(0)变化的重要气象要素。这些气象要素的较大贡献是由于其具有较大的多年相对变化率,而不是对ET_(0)有高度的敏感性。未来时期SSP245和SSP585情景下的汾渭平原ET_(0)相比历史时期分别增加4.2%和3.1%。汾渭平原ET_(0)的变化趋势、相对变化的空间分布差异主要表现在平原的东部与西部地区之间。本研究的高精度ET_(0)时空分布结果可为汾渭平原地区制定应对气候变化的适应性措施提供数据参考。

关键词：气候变化参考作物蒸散量汾渭平原气象要素贡献率

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旱作农田覆膜和秸秆碳投入对土壤团聚特性及作物产量的影响

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土壤学报 2024年第1期61卷 272-284页

作者：王钰皓庞津雯卫婷高飞刘恩科贾志宽张鹏西北农林科技大学农学院陕西杨凌712100 农业农村部西北黄土高原作物生理生态与耕作重点实验室陕西杨凌712100 甘肃省耕地质量建设保护总站兰州730020 中国农业科学院农业环境与可持续发展研究所北京100081

研究秸秆还田形式对旱作覆膜农田土壤团聚特性、有机碳含量及玉米产量的影响,为优化覆膜耕作措施,实现旱作覆膜农田可持续性生产提供理论依据。以长期定位旱作玉米覆膜农田(始于2012年)为研究对象,设置双垄沟覆膜(P)和传统平作(T),分别... 详细信息

研究秸秆还田形式对旱作覆膜农田土壤团聚特性、有机碳含量及玉米产量的影响,为优化覆膜耕作措施,实现旱作覆膜农田可持续性生产提供理论依据。以长期定位旱作玉米覆膜农田(始于2012年)为研究对象,设置双垄沟覆膜(P)和传统平作(T),分别施加秸秆(S)和生物质炭(C),以不还田为对照(N),共形成6个处理:覆膜秸秆还田(PS)、覆膜生物质炭还田(PC)、覆膜不还田(PN)、平作秸秆还田(TS)、平作生物质炭还田(TC)和平作不还田(TN)。测定土壤团聚体组成及团聚体有机碳含量,并分析了双垄沟覆膜和不同秸秆碳投入对土壤有机碳含量、团聚体稳定性及玉米产量的影响。研究结果表明,各秸秆还田处理较不还田处理均可显著(P0.25mm团聚体含量平均显著(P<0.05)提高47.32%,各双垄沟覆膜处理MWD和GMD较平作处理分别平均提高9.19%和4.15%;各还田处理可显著(P<0.05)提高0~60 cm土层土壤有机碳含量,其中PC和TC处理分别较对应PS和TS处理土壤有机碳含量提高2.60%和2.73%;各处理团聚体有机碳含量均随粒径增大而增大,秸秆碳投入可显著(P<0.05)提高各粒级团聚体有机碳含量,而双垄沟覆膜处理则降低了土壤有机碳及团聚体有机碳含量;还田方式、种植方式及土壤有机碳对玉米产量有促进作用,施加秸秆及生物质炭均能显著(P<0.05)提高旱作覆膜农田玉米产量,平均提高14.6%,而秸秆直接还田处理与生物质炭还田处理的增产效果无显著差异。综合分析,在双垄沟覆膜条件下投入秸秆碳能够明显提高土壤稳定性、土壤有机碳含量和作物产量,其中,双垄沟覆膜与生物质炭还田的耦合效应对改善农田土壤质量及地力提升有积极作用。

关键词：双垄沟覆膜土壤团聚特性有机碳玉米产量秸秆碳投入

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不同处理对玉米籽粒机械收获破碎率影响的研究

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作物杂志 2024年第4期 138-143页

作者：杨柯姜春霞张伟刘恩科翟广谦张冬梅山西农业大学山西有机旱作农业研究院/农业农村部有机旱作农业重点实验室(部省共建)/省部共建有机旱作农业国家重点实验室(筹)/有机旱作农业山西省重点实验室山西太原030031

为研究不同处理对玉米籽粒破碎率的影响,分析籽粒破碎率在实验室和实际机收下的关系,探索一种测试破碎率的便捷方式,设置不同的试验,包括品种、施氮量、播期、收获期,通过室内研磨测试不同孔径下籽粒的破碎率,并拟合机械收获过程中破碎... 详细信息

为研究不同处理对玉米籽粒破碎率的影响,分析籽粒破碎率在实验室和实际机收下的关系,探索一种测试破碎率的便捷方式,设置不同的试验,包括品种、施氮量、播期、收获期,通过室内研磨测试不同孔径下籽粒的破碎率,并拟合机械收获过程中破碎率曲线。结果表明,不同品种、施氮量、播期、收获期籽粒破碎率之间差异明显,籽粒类型偏角质、减氮25%、收获期适当推迟可以提升籽粒耐破碎性。籽粒机械收获时含水率与破碎率呈二次曲线关系,当含水率为21.95%时,破碎率最低,为4.32%;含水率与实验室内研磨籽粒孔径为2.36 mm筛子计算出的破碎率呈二次曲线关系,回归曲线方程分析相近。本研究通过室内研磨籽粒测试破碎率(2.36 mm)模拟籽粒机械实际收获时的破碎率,为选育适宜籽粒机收品种提供测试破碎率更灵活便捷的方式。

关键词：玉米籽粒收获耐破碎性破碎率

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Density functional theory investigation on lattice dynamics,elastic properties and origin of vanished magnetism in Heusler compounds CoMnVZ(Z=Al,Ga)

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Chinese Physics B 2021年第8期30卷 301-311页

作者： Guijiang Li enke liu Guodong liu Wenhong Wang Guangheng Wu College of Materials Science and Engineering Nanjing Tech UniversityNanjing 211816China State Key Laboratory for Magnetism Institute of PhysicsChinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China School of Materials Science and Engineering Hebei University of TechnologyTianjin 300130China

The lattice dynamics,elastic properties and the origin of vanished magnetism in equiatomic quaternary Heusler compounds CoMnVZ(Z=Al,Ga)are investigated by first principle calculations in this *** to the similar constituent atoms in CoMnVAl and CoMnVGa compounds,they are both stable in LiMgPdSn-type structure with comparable lattice size,phonon dispersions and electronic ***,we find that CoMnVAl is more structurally stable than ***,the increased covalent bonding component in CoMnVAl enhances its mechanical strength and Vickers hardness,which leads to better comprehensive mechanical properties than those of *** and importantly,structural and chemical compatibilities at the interface make non-magnetic semiconductor CoMnVAl and magnetic topological semimetals Co2MnAl/Ga more suitable to be grown in *** to atomic preferential occupation in CoMnVAl/Ga,the localized atoms Mn occupy C(0.5,0.5,0.5)Wyckoff site rather than B(0.25,0.25,0.25)and D(0.75,0.75,0.75)Wyckoff sites in LiMgPdSn-type structure,which results in symmetric band filling and consequently drives them to be ***,by tuning localized atoms Mn to occupy B(0.25,0.25,0.25)or/and D(0.75,0.75,0.75)Wyckoff sites in off-stoichiometric Co-Mn-V-Al/Ga compounds and keeping the total valence electrons as 24,newly compensated ferrimagnetic compounds are theoretically *** hope that our work will provide more choices for spintronic applications.

关键词： Heusler compounds CoMnVAl/Ga first principles calculations lattice dynamics elastic properties nonmagnetic semiconductor

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Electronic structures,magnetic properties,and martensitic transformation in all-d-metal Heusler-like alloys Cd2MnTM(TM=Fe,Ni,Cu)

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Chinese Physics B 2020年第8期29卷 407-412页

作者： Yong Li Peng Xu Xiaoming Zhang Guodong liu enke liu Lingwei Li Institute of Advanced Magnetic Materials School of Materials and Environmental EngineeringHangzhou Dianzi UniversityHangzhou 310012China Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang 110819China School of Materials Science and Engineering Hebei University of TechnologyTianjin 300130China Institute of Physics Chinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China

The electronic structures,magnetic properties,and martensitic transformation in all-d-metal Heusler-like alloys Cd2MnTM(TM=Fe,Ni,Cu)were investigated by the first-principles calculations based on density-functional *** results indicate that all three alloys are stabilized in the ferromagnetic L21-type *** total magnetic moments mainly come from Mn and Fe atoms for Cd2MnFe,whereas,only from Mn atoms for Cd2MnNi and *** magnetic moment at equilibrium lattice constant of Cd2MnFe(6.36μB)is obviously larger than that of Cd2MnNi(3.95μB)and Cd2MnCu(3.82μB).The large negative energy differences(ΔE)between martensite and austenite in Cd2MnFe and Cd2MnNi under tetragonal distortion and different uniform strains indicate the possible occurrence of ferromagnetic martensitic transformation(FMMT).The minimum total energies in martensitic phase are located with the c/a ratios of 1.41 and 1.33 for Cd2MnFe and Cd2MnNi,*** total moments in martensitic state still maintain large values compared with those in cubic *** study is useful to find the new all-d-metal Heusler alloys with FMMT.

关键词： all-d-metal Heusler-like alloys electronic structures magnetic properties martensitic transformation

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On the anomalous low-resistance state and exceptional Hall component in hard-magnetic Weyl nanoflakes

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Science China(Physics,Mechanics & Astronomy) 2021年第8期64卷 107-113页

作者： QingQi Zeng GangXu Gu Gang Shi JianLei Shen Bei Ding Shu Zhang XueKui Xi Claudia Felser YongQing Li enke liu Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Department of Physics and Astronomy University of CaliforniaLos Angeles 90095USA Max Planck Institute for Chemical Physics of Solids Dresden D-01187Germany Songshan Lake Materials Laboratory Dongguan 523808China

Magnetic topological materials, which combine magnetism and topology, are expected to host emerging topological states and exotic quantum phenomena. In this study, with the aid of greatly enhanced coercive fields in high-quality nanoflakes of the magnetic Weyl semimetal Co_(3)Sn_(2)S_(2), we investigate anomalous electronic transport properties that are difficult to reveal in bulk Co_(3)Sn_(2)S_(2) or other magnetic materials. When the magnetization is antiparallel to the applied magnetic field, the low longitudinal resistance state occurs, which is in sharp contrast to the high resistance state for the parallel case. Meanwhile, an exceptional Hall component that can be up to three times larger than conventional anomalous Hall resistivity is also observed for transverse transport. These anomalous transport behaviors can be further understood by considering nonlinear magnetic textures and the chiral magnetic field associated with Weyl fermions, extending the longitudinal and transverse transport physics and providing novel degrees of freedom in the spintronic applications of emerging topological magnets.

关键词： hard-magnetic material magnetic Weyl semimetal magnetoresistance Hall effect

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Anisotropic magnetoelastic response in the magnetic Weyl semimetal Co_(3)Sn_(2)S_(2)

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Science China(Physics,Mechanics & Astronomy) 2021年第5期64卷 82-90页

作者： Chang liu ChangJiang Yi XingYu Wang JianLei Shen Tao Xie Lin Yang Tom Fenne Uwe Stuhr ShiLiang Li HongMing Weng YouGuo Shi enke liu HuiQian Luo Beijing National Laboratory for Condensed Matter Physics Institute of PhysiesChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBejing 100190China Laboratory for Neutron Scattering and Imaging Paul Scherrer InstituteVlligen CH-5232Switzerland Songshan Lake Materials Laboratory Dongguan 523808China SCAS Centre for Excelence in Topological Quantum Computation Bejing 100190China Physical Science Laboratory Huairou National Comprehensive Science CenterBeijing 101400China

Co_(3)Sn_(2)S_(2) is a recently identified magnetic Weyl semimetal in Shandite compounds. Upon cooling, Co_(3)Sn_(2)S_(2) undergoes a ferromagnetic transition with c-axis polarized moments(0.3 μ_(B)/Co) around T_(C)= 175 K, followed by another magnetic anomaly around T_(A)≈ 140 K. A large intrinsic anomalous Hall effect is observed in the magnetic state below TC with a maximum of anomalous Hall angle near T_(A). Here, we report an elastic neutron scattering on the crystalline lattice of Co_(3)Sn_(2)S_(2) in a magnetic field up to 10 T. A strongly anisotropic magnetoelastic response is observed, while only a slight enhancement of the Bragg peaks is observed when B//c. The in-plane magnetic field(B//ab) dramatically suppresses the Bragg peak intensity probably by tilting the moments and lattice toward the external field direction. The in-plane magnetoelastic response commences from T_(C), and as it is further strengthened below T_(A), it becomes nonmonotonic against the field between T_(A) and T_(C) because of the competition from another in-plane magnetic order. These results suggest that a magnetic field can be employed to tune the Co_(3)Sn_(2)S_(2) lattice and its related topological states.

关键词： Weyl semimetal magneto-elastic coupling topological materials elastic neutron scattering ferromagnetism

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Spin excitations and spin wave gap in the ferromagnetic Weyl semimetal Co3Sn2S2

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Science China(Physics,Mechanics & Astronomy) 2021年第1期64卷 3-9页

作者： Chang liu JianLei Shen JiaCheng Gao ChangJiang Yi Di liu Tao Xie Lin Yang Sergey Danilkin GuoChu Deng WenHong Wang ShiLiang Li YouGuo Shi HongMing Weng enke liu HuiQian Luo Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing100190China Australian Centre for Neutron Scattering Australian Nuclear Science and Technology OrganizationLucas HeightsNSW2234Australia Songshan Lake Materials Laboratory Dongguan523808China Physical Science Laboratory Huairou National Comprehensive Science CenterBeijing101407China

We report a comprehensive neutron scattering study on the spin excitations in the magnetic Weyl semimetal Co3Sn2S2 with a quasi-two-dimensional *** in-plane and out-of-plane dispersions of the spin waves were revealed in the ferromagnetic ***,dispersive but damped spin excitations were found in the paramagnetic *** effective exchange interactions were estimated using a semi-classical Heisenberg model to consistently reproduce the experimental TCand spin ***,a full spin wave gap below Eg=2.3 meV was observed at T=4 *** value was considerably larger than the estimated magnetic anisotropy energy(~0.6 meV),and its temperature dependence indicated a significant contribution from the Weyl *** results suggest that Co3Sn2S2 is a three-dimensional correlated system with a large spin stiffness,and the low-energy spin dynamics can interplay with the topological electron states.

关键词： magnetic Weyl semimetal topological materials spin excitations neutron scattering

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