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Identifying the critical phosphorus balance for optimizing phosphorus input and regulating soil phosphorus effectiveness in a typical winter wheat-summer maize rotation system in North China

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Journal of Integrative Agriculture 2023年第12期22卷 3769-3782页

作者： XU Meng-ze WANG Yu-hong NIE Cai-e SONG Gui-pei XIN Su-ning LU Yan-li BAI You-lu ZHANG Yin-jie WANG Lei State Key Laboratory of Efficient utilization of Arid and Semi-arid Arable land in Northern China/Key Laboratory of Plant Nutrition and Fertilizer of Ministry of Agriculture and Rural Affairs Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081P.R.China College of Resources and Environment Henan Agricultural UniversityZhengzhou 450002P.R.China

Phosphorus(P)is a nonrenewable resource and a critical element for plant growth that plays an important role in improving crop *** P fertilizer application is widespread in agricultural production,which not only wastes phosphate resources but also causes P accumulation and groundwater ***,we hypothesized that the apparent P balance of a crop system could be used as an indicator for identifying the critical P input in order to obtain a high yield with high phosphorus use efficiency(PUE).A 12-year field experiment with P fertilization rates of 0,45,90,135,180,and 225 kg P_(2)O_(5)ha^(-1)was conducted to determine the crop yield,PUE,and soil Olsen-P value response to P balance,and to optimize the P *** yield stagnation occurred when the P fertilizer application exceeded a certain level,and high yield and PUE levels were achieved with annual P fertilizer application rates of 90-135 kg P_(2)O_(5)ha^(-1).A critical P balance range of 2.15-4.45 kg P ha^(-1)was recommended to achieve optimum yield with minimal environmental *** critical P input range estimated from the P balance was 95.7-101 kg P_(2)O_(5)ha^(-1),which improved relative yield(>90%)and PUE(90.0-94.9%).In addition,the P input-output balance helps in assessing future changes in Olsen-P values,which increased by 4.07 mg kg^(-1)of P for every 100 kg of P ***,the P balance can be used as a critical indicator for P management in agriculture,providing a robust reference for limiting P excess and developing a more productive,efficient and environmentally friendly P fertilizer management strategy.

关键词： yield of winter wheat and summer maize phosphorus balance phosphorus use efficiency Olsen-P critical phosphorus application rate

Tradeoff between productivity and stability across above-and below-ground communities

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Journal of Integrative Plant Biology 2024年第11期66卷 2321-2324页

作者： Zonghao Hu Haiyan Liu Junjie Yang Bin Hua Michael Bahn Shuang Pang Tingting Li Wei Yang Honghui Wu Xingguo Han Ximei Zhang State Key Laboratory of Efﬁcient utilization of Agricultural Water Resources Institute of Environment and Sustainable Development in AgricultureChinese Academy of Agricultural SciencesBeijing 100081China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China College of Forestry Henan Agricultural UniversityZhengzhou 450002China Department of Ecology University of InnsbruckInnsbruck 6020Austria State Key Laboratory of Efﬁcient utilization of Arid and Semi-arid Arable land in Northern China Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081China Key Laboratory of Arable land Quality Monitoring and Evaluation Ministry of Agriculture and Rural AffairsInstitute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081China

Because of the aggravated agricultural fertilization and combustion of fossil fuels,the nitrogen(N)deposition rate has increased from the pre-industrial levels of about 0.1–0.3 to as high as 10 g N m^(-2)year^(-1)in some developed countries,and it is predicted to increase similarly over the next 50 years in many developing countries(Galloway et al.,2004).

关键词： Trade stability ground

Evolution of Yellow River Delta Coastline Based on Remote Sensing from 1976 to 2014, China

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Chinese Geographical Science 2019年第2期29卷 181-191页

作者： WANG Kuifeng Shandong Institute of Geological Sciences Shandong Key Laboratory of Geological Process and Resource Utilization in Metallic Minerals Key Laboratory of Gold Mineralization Process and Resource Utilization Subordinate to the Ministry of Land and Resource Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and Technology School of Civil Engineering Shandong University

Coastal regions are threatened by natural processes, such as erosion driven by storm surges and the effect of jetties, as well as by human behavior. The coastline of the Yellow River Delta(YRD) was monitored using the general high-tide line method, which combines Remote sensing(RS) and geographic information system(GIS) technology, using multi-spectral scanner(MSS), thematic mapper(TM), and enhanced thematic mapper plus(ETM+) images of the YRD from 1976 to 2014 as a data source. The results demonstrated that the shape and length of the YRD coastline has changed dramatically since 1976. The course of the Diaokouhe channel has resulted in mainly inland erosion in the north, and is primarily marine erosion; therefore, it was termed an erosion-type estuary. However, the coastline of the Qingshuigou course has moved seaward, demonstrating an accretion stage, and was therefore termed an accretion-type estuary. The coastline advanced forward before 1997 and shrank after 2003 in the southern part of the river mouth, which was due to the shift in the river mouth in 1996. It has continually extended outward in the northern part of the river mouth from 2003 onward. The coastline in the southern part of the river mouth has moved randomly, with the occurrence of both erosion and sedimentation caused by land reclamation and sea wave intrusion. In most cases, the coastline has extended offshore, especially in the northern part of the river mouth. The YRD coastline has changed frequently and rapidly from 1992 to 2014. The river mouth channel, river water and sediments, and precipitation were the major factors affecting the YRD. The YRD coastline was mainly in an accretion stage during flow periods. The erosion rate decreased and tended to be stable during a dry period. The coastline was basically stable when dry periods occurred over a long period. The location of Yellow River ports and sea erosion were the main factors driving coastline changes. The coastline was mainly influenced

关键词： coastline evolution remote sensing Yellow River Delta morphological evolution social-ecological challenge

Collectorless flotation of marmatite with pine oil

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Rare Metals 2017年第2期36卷 147-154页

作者： Zheng-Bin Deng Xiong Tong Alejandro López Valdivieso Xiao Wang Xian Xie Faculty of land and Resource Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Complex Nonferrous Metal Resources Clean utilization Kunming 650093China Yunnan Province Engineering Research Center for Reutilization of Metal Tailings Resources Kunming 650093China Laboratory of Surface Chemistry Institute of Metallurgy Universidad Autonoma de San Luis PotosiC.P.78210 San Luis PotosiMexico

The interaction between pine oil and marmatite without collectors and activators was investigated by flotation,scanning electron microscope and energy-dispersive spectrometer（SEM-EDS）,infrared（IR） spectroscopy,Zeta potential,and first-principle theory *** flotation results show that marmatite exhibits considerable floatability with the addition of pine ***-EDS results show that carbon atomic ratios on the surface are significantly high,which suggests that the flotation of marmatite is caused by the adsorption of pine *** evidence of the adsorption mechanism was given by IR,and Zeta potential examining pine oil depends on the physical adsorption on the surface *** first-principle theory calculations indicate that pine oil molecule adsorbs on Zn and Fe atom surfaces by ionic bond and covalent bond of adsorption energies of-1.23and-1.51 eV,respectively.P orbital of O atom,s orbital of Zn atom,and d orbital of Fe are the major participants.

关键词： Pine oil Marmatite Collectorless flotation

Temporal Changes of Ecosystem Carbon Stocks in Rubber Plantationsin Xishuangbanna; Southwest China

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Pedosphere 2017年第4期27卷 737-746页

作者： SUN Yanci MA Youxin CAO Kunfang LI Hongmei SHEN Jinxiang LIU Wenjun DI Liang MEI Cencen Center for Integrative Conservation Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglun 666303China Yunnan College of Business Management Kunming 650106China University of Chinese Academy of Sciences Beijing 100095China State Key Laboratory for Conservation and utilization of Subtropical Agro-Bioresources and College of ForestryGuangxi UniversityNanning 530004China Yunnan land and Resources Vocational College Kunming 650217China

Rubber(Hevea brasiliensis) plantations have been expanded rapidly in tropical regions of Southwest China and cover more than20% of land area in *** studies have addressed changes of soil C stocks in rubber plantations;however,estimates of total ecosystem C stocks and their temporal changes in rubber plantations have been inadequately *** study calculated C stocks in soil,biomass,litter,and dry rubber(latex),and estimated the total ecosystem C stocks of rubber plantations in an age sequence of 3-,7-,9-,21-,27-,and 34-year-old in Xishuangbanna,Southwest *** total C stocks in rubber plantations ranged from 150.3 to 283.7 Mg C ha^(-1),with a mean of 213.4 Mg C ha^(-1).The plantations≤9-year-old had significantly lower(P<0.05)total C stocks than those older than 9 *** stocks in soil(mass equivalent) were between 107.1–170.5 Mg C ha^(-1) and in living biomass were between 2.8–95.7 Mg C ha^(-1),representing the largest and the second largest C components in a rubber plantation *** of dry rubber C stock resulted in an underestimate of 7.8%–14.2% of the total C stock in the rubber plantations older than 9 years,which was much larger than the contribution of litter C stock(less than 2%).

关键词： age sequence, carbon sequestration, dry rubber, Hevea brasiliensis, litter

Tectono-Thermal Evolution, Hydrocarbon Filling and Accumulation Phases of the Hari Sag, in the Yingen-Ejinaqi Basin, Inner Mongolia,Northern China

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Acta Geologica Sinica(English Edition) 2018年第3期92卷 1157-1169页

作者： YANG Peng REN Zhanli XIA Bin TIAN Tao ZHANG Yong QI Kai REN Wenbo State Key Laboratory of Continental Dynamics Department of Geology Northwest University Guangdong Key Laboratory of Offshore Oil Exploration and Development School of Marine ScienceSun Yat-sen University Radiogenic Isotope Facility School of Earth and Environmental Sciences The University of Queensland State Key Laboratory of Ore Deposit Geochemistry Chinese Academy of Sciences Key Laboratory Coal Resource Exploration and comprehensive utilization Ministry of Land and Resources

This work restored the erosion thickness of the top surface of each Cretaceous formations penetrated by the typical well in the Hari sag, and simulated the subsidence burial history of this well with software BasinMod. It is firstly pointed out that the tectonic subsidence evolution of the Hari sag since the Cretaceous can be divided into four phases: initial subsidence phase, rapid subsidence phase,uplift and erosion phase, and stable slow subsidence phase. A detailed reconstruction of the tectonothermal evolution and hydrocarbon generation histories of typical well was undertaken using the EASY R% model, which is constrained by vitrinite reflectance(R) and homogenization temperatures of fluid inclusions. In the rapid subsidence phase, the peak period of hydrocarbon generation was reached at c.a.105.59 Ma with the increasing thermal evolution degree. A concomitant rapid increase in paleotemperatures occurred and reached a maximum geothermal gradient of about 43-45℃/km. The main hydrocarbon generation period ensued around 105.59-80.00 Ma and the greatest buried depth of the Hari sag was reached at c.a. 80.00 Ma, when the maximum paleo-temperature was over 180℃.Subsequently, the sag entered an uplift and erosion phase followed by a stable slow subsidence phase during which the temperature gradient, thermal evolution, and hydrocarbon generation decreased gradually. The hydrocarbon accumulation period was discussed based on homogenization temperatures of inclusions and it is believed that two periods of rapid hydrocarbon accumulation events occurred during the Cretaceous rapid subsidence phase. The first accumulation period observed in the Bayingebi Formation(Kb) occurred primarily around 105.59-103.50 Ma with temperatures of 125-150℃. The second accumulation period observed in the Suhongtu Formation(Ks) occurred primarily around84.00-80.00 Ma with temperatures of 120-130℃. The second is the major accumulation period, and the accumulation mainly occurred in the Late Cr

关键词： fluid inclusion erosion thickness subsidence burial history tectono-thermal evolution hydrocarbon generation history hydrocarbon accumulation phase Inner Mongolia China

Glacier Relics of the Last Glacial and Holocene Periods Discovered in the Middle-low Mountains of Eastern China: Sedimentary Sequences and Environmental Evolution of Mengshan Mountain in Shandong Province since 80 ka

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Acta Geologica Sinica(English Edition) 2020年第1期94卷 141-151页

作者： WANG Zhaobo WANG Jiangyue HE Lelong ZHANG Jian The Key Laboratory of Gold Mineralization Process and Resource utilization of the Ministry of land and Resources Jinan 250013China The Administration for Yimengshan National Geopark LinyiShandong 273304China Shandong Compass Mineral Exploration co. LtdLinyiShandong 276006China The College of Geography and Travel Normal University of QufuRizhaoShandong 276800China The Qingdao Institute of Marine Geology-QIMG QingdaoShandong 266071China

The goal of this research study is to describe academic issues which have been debated in the field of Chinese geosciences for a century. In 1922, Jonquei S. Lee(Li Siguang) discovered Quaternary glacial relics at Taihang Mountainin eastern China. In 1947, he published his research findings in the magazine Mount Lushan in Glacial Age. The research results had established three Ice Ages: Poyang(Gonzi), Dagu(Minde), and Lushan(Lisi). However, at that time, no Wurm glacial relics of the last Ice Age had been found in Lushan Mountain. Since then, the research team represented by Shi Yafeng, who is considered to be "the father of glaciers in China", questioned Jonquei S. Lee’s research results and concluded that "Professor Jonquei S. Lee’s Quaternary glacier research in Lushan Mountain having misread the debris flow". In 2005, the "middle-low mountains" in eastern China were finally defined as follows: "We clearly and unambiguously believe that there were no glacial activities in the middle-low mountainous areas of eastern China(east of 102° to 104°E;below 3,000 and 2,500 m) during the Quaternary Period". Currently, the long-standing academic debate appears to have come to a conclusion. As of 2015, the author and others began to investigate and study the Quaternary glacial relics in Mengshan Mountain(1,156 m above sea level), Shandong Province, one of the "middle-low mountains" of eastern China. The relics have been observed to posses the systematic features of glacial erosion, trough and valley striations, and moraine deposits. The applied dating method shave confirmed that there were not only glacial relics of the last Ice Age(Wurm), but also Holocene glacial relics in the Mengshan Mountain area. Therefore, in order to further establish the corresponding relationship between the glacier, loess, stream sediment series, and MIS in the Mengshan Mountain area, a large number of chronological studies have been carried out regarding the various types of sediments in the area

关键词： OSL CRN MIS glacial relics last Ice Age Holocene Eastern China

Evaluation of coordinated development of regional resources and economy around Shandong Peninsula urban agglomerations

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Journal of Groundwater Science and Engineering 2016年第3期4卷 220-228页

作者： LI Na WANG Kui-feng Shandong Xiehe University Jinan 250109China Shandong Institute of Geological Sciences Shandong Key Laboratory of Geological Process and Resource Utilization in Metallic MineralsKey Laboratory of Gold Mineralization Process and Resource Utilization Subordinate to the Ministry of Land and ResourceJinan 250013China

Promoting coordinated development of resources and environment is an important aspect of building a harmonious society and ecologically sustainable civilization. Here we provide scientific basis to promote the development of ecologically sensitive civilization, via a mathematical statistics method that calculates the degree of coordinated development. This model is of great practical and social significance, providing strength to research around coordinated development of resources and economy. Based on evaluation of characteristics of the present resource environment and economic development of Shandong Peninsula city group, a coordinated measure of resource environment and economic development was calculated. Overall, the highest coordination measurement was found for Weihai, followed by Yantai, Qingdao, Ji'nan, Weifang, Rizhao, Zibo and Dongying. According to evaluation results of coordination measures for each city, we put forward suggestions for sustainable development of Shandong Peninsula region.

关键词： Shandong Peninsula Urban Agglomerations Resources Economic development Coordinated development model Sustainable development

Reagent types and action mechanisms in ilmenite flotation:A review

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International Journal of Minerals,Metallurgy and Materials 2022年第9期29卷 1656-1669页

作者： Jiaozhong Cai Jiushuai Deng Liang Wang Mingzhen Hu Hongxiang Xu Xiaoan Hou Bozeng Wu Shimei Li School of Chemical and Environmental Engineering China University of Mining and Technology(Beijing)Beijing 100083China ZHONGGUANCUN Green Mine Industry Alliance Beijing 100083China Liuzhou China-Tin Nonferrous Design and Research Institute Co. Ltd.CHINA TIN GROUPLiuzhou 545006China State Key Laboratory of Complex Nonferrous Metal Resources Clean utilization Faculty of Land Resource EngineeringKunming University of Science and TechnologyKunming 650093China

Ilmenite is an essential mineral for the extraction of *** physical separation methods have difficulty recovering fine ilmenite,and dressing plants have begun applying flotation to recover *** interaction of reagent groups with Ti and Fe sites on the ilmenite surface dramatically influences the ilmenite ***,the investigation on Fe sites has received more attention because the activity of Ti is lower than that of *** the activators on ilmenite flotation,most are metal ions but typically lead *** metal ions of activators promote ilmenite flotation by increasing the active sites on the ilmenite *** reagents have a better selective separation of ilmenite than single reagents due to their synergistic *** the lead ion(Pb^(2+))and the benzyl hydroxamic acid(BHA)into a Pb-BHA complex has a marked effect on ilmenite flotation,which puts forward a new idea of developing combined reagents for ilmenite *** review considers reagent types and action mechanisms in ilmenite *** the basis of the analysis of previous research,a brief future outlook of reagent types and action mechanisms in ilmenite flotation is also proposed in this study.

关键词： ilmenite flotation reagent action mechanism combined reagents