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

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(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

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An optimized strategy of nitrogen-split application based on the leaf positional differences in chlorophyll meter readings

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Journal of Integrative Agriculture 2024年第8期23卷 2605-2617页

作者： Gaozhao Wu Xingyu Chen Yuguang Zang Ying Ye Xiaoqing Qian Weiyang Zhang Hao Zhang Lijun Liu Zujian Zhang Zhiqin Wang Junfei Gu Jianchang Yang Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Key Laboratory of Crop Cultivation and Physiology/Agricultural College Yangzhou UniversityYangzhou 225009China Jiangsu Co-Innovation center for Modern Production Technology of Grain Crops Yangzhou UniversityYangzhou 225009China Key Laboratory of Arable land Quality Monitoring and Evaluation Ministry of Agriculture and Rural AffairsYangzhou UniversityYangzhou 225127China

Modern rice production faces the dual challenges of increasing grain yields while reducing inputs of chemical ***,the disequilibrium between the nitrogen(N)supplement from the soil and the demand for N of plants is a serious obstacle to achieving these ***-based diagnosis can help farmers make better choices regarding the timing and amount of topdressing N *** objective was to evaluate a non-destructive assessment of rice N demands based on the relative SPAD value(RSPAD)due to leaf positional *** this study,two field experiments were conducted,including a field experiment of different N rates(Exp.I)and an experiment to evaluate the new strategy of nitrogen-split application based on RSPAD(***).The results showed that higher N inputs significantly increased grain yield in modern high yielding super rice,but at the expense of lower nitrogen use efficiency(NUE).The N nutrition index(NNI)can adequately differentiate situations of excessive,optimal,and insufficient N nutrition in rice,and the optimal N rate for modern high yielding rice is higher than conventional *** RSPAD is calculated as the SPAD value of the top fully expanded leaf *** value of the third leaf,which takes into account the non-uniform N distribution within a *** RSPAD can be used as an indicator for higher yield and NUE,and guide better management of N fertilizer ***,we developed a new strategy of nitrogen-split application based on RSPAD,in which the N rate was reduced by 18.7%,yield was increased by 1.7%,and the agronomic N use efficiency was increased by 27.8%,when compared with standard farmers'*** strategy of N fertilization shows great potential for ensuring high yielding and improving NUE at lower N inputs.

关键词： canopy crop management practices nitrogen nitrogen nutrition index rice SPAD

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Afforestation with an age-sequence of Mongolian pine plantation promotes soil microbial residue accumulation in the Horqin Sandy land, china

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Journal of Arid land 2024年第4期16卷 567-579页

作者： GUO Jingwen SONG Xueshu WANG Xiao DU Zhangliu LU Sen State Key Laboratory of Efficient Production of Forest Resources Research Institute of ForestryChinese Academy of ForestryBeijing 100091China Co-Innovation center for Sustainable Forestry in Southern china Nanjing Forestry UniversityNanjing 210037China College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193China

land use change affects the balance of organic carbon(C)reserves and the global C *** residues are essential constituents of stable soil organic C(SOC).However,it remains unclear how microbial residue changes over time following *** this study,16-,23-,52-,and 62-year-old Mongolian pine stands and 16-year-old cropland were studied in the Horqin Sandy land,*** analyzed changes in SOC,amino sugar content,and microbial parameters to assess how microbial communities influence soil C transformation and *** results showed that SOC storage increased with stand age in the early stage of afforestation but remained unchanged at about 1.27-1.29 kg/m2 after 52 ***,there were consistent increases in amino sugars and microbial residues with increasing stand *** stand age increased from 16 to 62 a,soil pH decreased from 6.84 to 5.71,and the concentration of total amino sugars increased from 178.53 to 509.99 mg/kg.A significant negative correlation between soil pH and the concentration of specific and total amino sugars was observed,indicating that the effects of soil acidification promote amino sugar stabilization during *** contrast to the Mongolian pine plantation of the same age,the cropland accumulated more SOC and microbial residues because of fertilizer *** Mongolian pine plantation with different ages,there was no significant change in calculated contribution of bacterial or fungal residues to SOC,suggesting that fungi were consistently the dominant contributors to SOC with increasing *** results indicate that afforestation in the Horqin Sandy land promotes efficient microbial growth and residue accumulation in SOC stocks and has a consistent positive impact on SOC persistence.

关键词： soil organic matter stand age biomarker amino sugars microbial residues

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Phosphorus lights up the trade-off between growth and immunity

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Molecular Plant 2024年第5期17卷 689-690页

作者： Wenyuan Ruan Meina Guo Keke Yi State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable land in Northern china/Key Laboratory of Plant Nutrition and Fertilizer Ministry of AgricultureInstitute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijingChina State Key Laboratory of Efficient Production of Forest Resources/National Engineering research center of Tree Breeding and Ecological Restoration College of Biological Sciences and TechnologyBeijing Forestry UniversityBeijingChina

How plants respond simultaneously to various biotic and abiotic stresses to balance growth and immunity is an old but vibrant *** need to effectively integrate multiple signaling inputs to make the final decision and,thus,use limited resources ***,plant secondary metabolites,including phytohormones,are the key to modulate investment of resources into immunity or ***,the molecular mechanisms underlying this allocation dilemma are far from being understood.

关键词： immunity lights integrate

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Reduced magma generation and its implications for the Pulang giant porphyry Cu-polymetallic deposit in Northwest Yunnan,china

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Acta Geochimica 2024年第4期43卷 802-813页

作者： Jingwei Guan Tao Ren Lei Wang Shenjin Guan Lianrong Wu Baosheng Shi Faculty of land Resources Engineering Kunming University of Science and TechnologyKunming 650093People’s Republic of China Diqing Nonferrous Metals Co. LtdShangri-La 674400People’s Republic of China

The Pulang giant porphyry Cu-Mo polymetallic deposit is located in the Zhongdian area in the center of the Sanjiang Tethys tectonic domain,which was formed by the westward subduction of the Garze-Litang oceanic slab beneath the Zhongza ***-pyrrhotite-pyritemolybdenite occurs as disseminations,veins,veinlets,and stockworks distributed in the K-silicate alteration zone in the monzonite porphyry,which is superimposed by *** chemical compositions of biotite and amphibole analyzed by electron probe microanalysis(EPMA)indicate that the ore-forming magma and exsolved fluids experienced a continuous decrease in the oxygen fugacity(fO_(2)).Primary amphibolite and biotite(type I)crystallized at relatively high temperatures(744-827°C)and low fO_(2)(log fO_(2)=−12.26 to−11.91)during the magmatic *** fluids exsolved from the magma have a relatively lower temperature(621-711°C)and fO_(2)(log fO_(2)=−14.36 to−13.32)than the original *** addition,the presence of a high abundance of pyrrhotite and an insufficiency of primary magnetite and sulfate in the ore(i.e.,anhydrite and gypsum)indicate that the deposit may be a reduced porphyry *** and fluid fO_(2)results,combined with previous research on magmatic fO_(2)at the Pulang deposit,indicate that the magma associated with the reduced Pulang ore assemblages was initially generated as a highly oxidized magma that was subsequently reduced by sedimentary rocks of the Tumugou Formation.

关键词： Porphyry deposit Oxygen fugacity(fO_(2)) Contamination of surrounding rock Pulang Zhongdian arc

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Energy-efficient computation offloading assisted by RIS-based UAV

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The Journal of china Universities of Posts and Telecommunications 2024年第1期31卷 37-48页

作者： Li Linpei Zhao Chuan Su Yu Huo Jiahao Huang Yao Li Haojin School of Intelligence Science and Technology University of Science and Technology BeijingBeijing 100083China Institute of Artificial Intelligence University of Science and Technology BeijingBeijing 100083China Shunde Innovation School University of Science and Technology BeijingFoshan 528399China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China research Department of 5G and Drone China Mobile(Chengdu)Institute of Research and DevelopmentChengdu 610200China College of Communication Engineering Chengdu University of Information TechnologyChengdu 610225China research and Development center Sony(China)LimitedBeijing 100027China

The new applications surge with the rapid evolution of the mobile *** explosive growth of the data traffic aroused by the new applications has posed great computing pressure on the local *** is essential to innovate the computation offloading methods to alleviate the local computing burden and improve the offloading *** edge computing(MEC)assisted by reflecting intelligent surfaces(RIS)-based unmanned aerial vehicle(UAV)is a promising method to assist the users in executing the computation tasks in proximity at low *** this paper,we propose an energy-efficient MEC system assisted by RIS-based UAV,where the UAV with RIS mounted relays the computation tasks to the MEC *** energy efficiency maximization problem is formulated by jointly optimizing the UAV's trajectory,the transmission power of all users,and the phase shifts of the reflecting elements placed on the *** that the optimization problem is non-convex,we propose a deep deterministic policy gradient(DDPG)-based *** combining the DDPG algorithm with the energy efficiency maximization problem,the optimization problem can be ***,the numerical results are illustrated to show the performance of the system and the superiority compared with the benchmark schemes.

关键词： mobile edge computing unmanned aerial vehicle reflecting intelligent surface

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On optimal charging scheduling for electric vehicles with wind power generation

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Fundamental research 2024年第4期4卷 951-960页

作者： Junjie Wu Qing-Shan Jia center for Intelligent and Networked Systems(CFINS) Department of AutomationBeijing National Research Center for Information Science and Technology(BNRist)TsinghuaUniversityBeijing100084China Huawei Technologies Co.Ltd Shenzhen 518129China

We consider the scheduling of battery charging of electric vehicles(EVs)integrated with renewable power *** increasing adoption of EVs and the development of renewable energies contribute importance to this *** optimization of charging scheduling is challenging because of the large action space,the multi-stage decision making,and the high *** solve this problem is time-consuming when the scale of the system is *** is urgent to develop a practical and efficient method to properly schedule the charging of *** contribution of this work is ***,we provide a sufficient condition on which the charging of EVs can be completely self-sustained by distributed *** algorithm is proposed to obtain the optimal charging policy when the sufficient condition ***,the scenario when the supply of the renewable power generation is deficient is *** prove that when the renewable generation is deterministic there exists an optimal policy which follows the modified least laxity and longer remaining processing time first(mLLLP)***,we provide an adaptive rule-based algorithm which obtains a near-optimal charging policy efficiently in general *** test the proposed algorithm by numerical *** results show that it performs better than the other existing rule-based methods.

关键词： Electric vehicle Charging scheduling Wind power Optimal policy Renewable energy

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What role do emission trading schemes,energy innovation,and technology transfer play in sustainable recovery?A perspective from BRICS economies

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Geoscience Frontiers 2024年第4期15卷 505-517页

作者： YunQian Zhang Ching-Chi Hsu School of Finance Fuzhou University of International Studies and TradeFuzhou 350202China City University of Macao Avenida Padre Tomás Pereira TaipaMacaoChina Carbon Economy research center Fuzhou University of International Studies and TradeFuzhou 350202China

To ensure long-run sustainability,it is imperative to achieve the goal of zero-carbon emissions without compromising economic *** whether BRICS economies,which are an attractive set of countries due to their rapid economic growth and high emissions,can shift towards sustainability with the support of policy measures,is a question which needs to be *** article investigates the impact of emission trading schemes,energy innovation,technology transfer,population growth,and inflation on the economic performance of BRICS economies(2001-2020).The outcomes of the CS-ARDL and PMG estimators reveal that carbon taxes,carbon finance,energy innovation,technology transfer,population growth,and inflation have positive effects on economic *** light of the evidence,policy insights are recommended to achieve a win-win situation for economic and environmental performance.

关键词： Emission trading schemes Carbon taxes Carbon finance Energy innovation Technology transfer Economic performance

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Coordinated responses of leaf and nodule traits contribute to the accumulation of N in relay intercropped soybean

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Journal of Integrative Agriculture 2024年第6期23卷 1910-1928页

作者： Ping Chen Qing Du Benchuan Zheng Huan Yang Zhidan Fu Kai Luo Ping Lin Yilin Li Tian Pu Taiwen Yong Wenyu Yang College of Agronomy Sichuan Agricultural University/Sichuan Engineering Research Center for Crop Strip Intercropping System/Key Laboratory of Crop Ecophysiology and Farming System in SouthwestMinistry of Agriculture and Rural AffairsChengdu 611130China Crop research Institute Sichuan Academy of Agricultural SciencesChengdu 610066China

Maize(Zea mays L.)-soybean(Glycine max ***.)relay intercropping provides a way to enhance land ***,the late-planted soybean suffers from shading by the *** maize harvest,how the recovery growth influences the leaf and nodule traits remains unclear.A three-year field experiment was conducted to evaluate the effects of genotypes,i.e.,supernodulating(nts1007),Nandou 12(ND12),and Guixia 3(GX3),and crop configurations,i.e.,the interspecific row spacing of 45(I45),60(I60),75 cm(I75),and sole soybean(SS),on soybean recovery growth and N *** results showed that intercropping reduced the soybean total leaf area(LA)by reducing both the leaf number(LN)and unit leaflet area(LUA),and it reduced the nodule dry weight(NW)by reducing both the nodule number(NN)and nodule diameter(ND)compared with the *** correlation and principal component analysis(PCA)indicated a co-variability of the leaf and nodule traits in response to the genotype and crop configuration *** the recovery growth stages,the compensatory growth promoted soybean growth to reduce the gaps of leaf and nodule traits between intercropping and *** relative growth rates of ureide(RGR_U)and nitrogen(RGR_N)accumulation were higher in intercropping than in *** achieved more significant sucrose and starch contents compared with ***12 and GX3 showed more robust compensatory growth than nts1007 in *** the recovery growth of relay intercropping soybean improved biomass and nitrogen accumulation,ND12 gained a more significant partial land equivalent ratio(pLER)than *** I60 treatment achieved more robust compensation effects on biomass and N accumulation than the other ***,I60 showed a higher nodule sucrose content and greater shoot ureide and N accumulation than ***,intercropping ND12 with maize using an interspecific row spacing of 60 cm was optimal for both yield advantage and N accumulation.

关键词： relay intercropping genotype crop configuration symbiotic nitrogen fixation soybean nodule

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How Does Government ProcurementPromote Enterprise Innovation?—On the Synergy between Demand-Pull and Supply-Push of Innovation Policies

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Frontiers of Economics in china-Selected Publications from Chinese Universities 2024年第1期19卷 1-29页

作者： SUN Wei YE Chusheng Economics and Management School Wuhan UniversityWuhan 430072China center for Economic Development research(CEDR) Wuhan UniversityWuhan 430072China

The promotion of technological innovation in firms requires both the supply-push and the *** accurately identify,assess,and further enhance the incentive effects of the policies of government procurement for innovation in china,this paper uses the text analysis method to identify government procurement for innovation from more than 640,000 pieces of government procurement contracts and conducts an empirical analysis based on the data of china's A-share listed firms from 2015 to *** study finds that government procurement for innovation significantly promotes corporate innovation by increasing the expected market returns,reducing R&D uncertainty,and easing financing ***,local government procurement for innovation,central government procurement for innovation,and procurement for innovation by universities and research institutes bring more significant innovation incentives for firms;and government procurement for innovation generates stronger innovation incentives for firms in strategic and emerging industries,private firms,and small-and medium-sized *** analysis reveals that demandside innovation procurement and supply-side innovation subsidies generally have mutually reinforcing synergies on corporate *** policy synergies vary depending on the levels of corporate innovation and the orders of policy *** terms of the levels of corporate innovation,the two-sided policies has mutually complementary effects on innovation-leading firms and mutually exclusive effects on innovation-lagging *** the perspective of the orders of policy implementation,the strategy of supply-side subsidies first,and demand-side procurement second is more effective in promoting corporate innovation than the strategies of demand-side procurement first and supply-side subsidies second,and supply-side subsidies and demand-side procurement *** study helps deepen the understanding of demand-side innovation sup

关键词： government procurement government procurement for innovation corporate innovation innovationpolicy

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