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Environmental benefits and farmers' adoption of winter cover crops in the North China Plain

Pedosphere 2024年第1期34卷 159-169页

作者： shufang guo Yitao ZHANG Limei ZHAI Jian LIU Hongyuan WANG Hongbin LIU State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China Key Laboratory of Nonpoint Source Pollution ControlMinistry of Agriculture and Rural AffairsInstitute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081China Institute of Agricultural Environment and Resources Yunnan Academy of Agricultural SciencesKunming 650205China Shandong Yucheng Agro-ecosystem National Observation Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China The Norwegian Institute of Bioeconomy Research(NIBIO) Akershus 1431Norway

The introduction of cover crops into monoculture systems to improve soil health has been widely adopted worldwide. However, little is known about the environmental risks and application prospects of different cover crops in spring maize(Zea mays L.) monocultures proposed in the North China Plain. A pot experiment was conducted to evaluate the effects of different winter cover crops on subsequent maize yield, soil fertility, and environmental risks of nitrogen(N) loss, and a questionnaire survey was conducted to examine factors influencing farmers' willingness to adopt cover crops in the North China Plain. Based on the same fertilization regime during the maize growing period, four winter cover crop treatments were set up, including bare fallow, hairy vetch(Vicia villosa Roth.), February orchid(Orychophragmus violaceus), and winter oilseed rape(Brassica campestris L.). The results indicated that winter cover crops significantly increased subsequent maize yield and soil organic carbon, total N, and microbial biomass carbon and N compared with the bare fallow treatment.The incorporation of cover crops led to a negligible increase in nitrous oxide(N_(2)O) emissions and had a very limited effect on ammonia(NH_(3)) emissions.The incorporation of February orchid and winter oilseed rape decreased nitrate leaching compared with the hairy vetch treatment in the maize growing season.The N losses via N_(2)O and NH_(3) emissions and N leaching accounted for 71%–84% of the N surplus. However, yield increase and environmental benefits were not the main positive factors for farmers to accept cover crops. Financial incentive was rated by 83.9% of farmers as an “extremely important” factor, followed by other costs, when considering winter cover cropping. These results indicate that the environmental benefits depend on the type of cover crop. Maintaining high levels of soil fertility and maize yield, providing sufficient subsidies, and encouraging large-area cultivation of cover crops are critical measures to promote winter cover c

关键词： cover crop N leaching NH_(3)emission N_(2)O emission spring maize willingness to accept

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Effects and mechanism of freeze-thawing cycles on the soil N2O fluxes in the temperate semi-arid steppe

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Journal of Environmental Sciences 2017年第6期29卷 192-201页

作者： Liqin Wang Yuchun Qi Yunshe Dong qin Peng shufang guo Yunlong He Zhaolin Li Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China University of the Chinese Academy of Sciences Beijing 100049China

High nitrous oxide （N20） emissions during freeze-thawing period （FFP） have been observed in many different ecosystems. However, the knowledge about the dynamic of soil N20 emissions and its main driving mechanism during the freeze-thawing processes in grassland ecosystem is still limited. An in-situ experiment was conducted during the FTP on the sites with 0 and 15% surplus of the average rainfall and two levels of N addition （0,10 g N/（m2-year）） during growing season （marked as WON0, WISN0, WONI0, WISNI0, respectively） to explore the effects of water and N background on soil N20 emissions during FTPs and the relationship between soil N20 emissions and environmental factors. The results indicated that water and N treatments conducted during growing season did not show significant effect on the N20 effluxes of FTP, but the soil mineral N contents of WONI0 treatment were significantly higher than those of WON0, WI5N0, WI5NI0 treatments （p 〈 0.05）. The soil PLFA concentrations of microbial groups monitored during 2015 spring freeze-thawing period （2015S-FTP） were lower than those during winter freeze-thawing period of 2014 （2014W-FTP）, while cumulative soil N20 emissions of 2015S-FTP were higher than those of 2014W-FFP. The correlations between soil N20 effluxes and most of the measured environmental factors were insignificant, multiple stepwise regression analysis indicated that the soil temperature, soil NH$-N content and air temperature were the major environmental factors which significantly influenced the N20 effluxes during 2014W-FTP, and air temperature and son water content were the significant influencing factors during 2015S-FTP.

关键词： Temperate semi-arid steppeNitrous oxideFreeze-thawing periodWater and nitrogen addition

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Litter decomposition and C and N dynamics as affected by N additions in a semi-arid temperate steppe, Inner Mongolia of China

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Journal of Arid Land 2014年第4期6卷 432-444页

作者： Qin PENG YuChun QI YunShe DONG YaTing HE ShengSheng XIAO XinChao LIU LiangJie SUN JunQiang JIA shufang guo CongCong CAO Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences Jiangxi Provincial Research Institute for Soil and Water Conservation

Litter decomposition is the fundamental process in nutrient cycling and soil carbon（C） sequestration in terrestrial ecosystems. The global-wide increase in nitrogen（N） inputs is expected to alter litter decomposition and,ultimately, affect ecosystem C storage and nutrient status. Temperate grassland ecosystems in China are usually N-deficient and particularly sensitive to the changes in exogenous N additions. In this paper, we conducted a 1,200-day in situ experiment in a typical semi-arid temperate steppe in Inner Mongolia to investigate the litter decomposition as well as the dynamics of litter C and N concentrations under three N addition levels（low N with 50 kg N/（hm2？a）（LN）, medium N with 100 kg N/（hm2？a）（MN）, and high N with 200 kg N/（hm2？a）（HN）） and three N addition forms（ammonium-N-based with 100 kg N/（hm2？a） as ammonium sulfate（AS）, nitrate-N-based with 100 kg N/（hm2？a） as sodium nitrate（SN）, and mixed-N-based with 100 kg N/（hm2？a） as calcium ammonium nitrate（CAN）） compared to control with no N addition（CK）. The results indicated that the litter mass remaining in all N treatments exhibited a similar decomposition pattern： fast decomposition within the initial 120 days, followed by a relatively slow decomposition in the remaining observation period（120–1,200 days）. The decomposition pattern in each treatment was fitted well in two split-phase models, namely, a single exponential decay model in phase I（〈398 days） and a linear decay function in phase II（≥398 days）. The three N addition levels exerted insignificant effects on litter decomposition in the early stages（〈398 days, phase I; P〉0.05）. However, MN and HN treatments inhibited litter mass loss after 398 and 746 days, respectively（P〈0.05）. AS and SN treatments exerted similar effects on litter mass remaining during the entire decomposition period（P〉0.05）. The effects of these two N addition forms differed greatly from those of CAN after 746 and 1,053 days, respectively（P〈0.05）. During the decomposition period, N concentrations in the decomposing litter

关键词： litter decomposition N deposition N level N form C sequestration semi-arid temperate grassland

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Effects of water and nitrogen addition on vegetation carbon pools in a semi-arid temperate steppe

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Journal of Forestry Research 2016年第3期27卷 621-629页

作者： Junqiang Jia Yunshe Dong Yuchun Qi Qin Peng Xinchao Liu Liangjie Sun shufang guo Yunlong He Congcong Cao Zhongqing Yan Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 People's Republic of China University of the Chinese Academy of Sciences Beijing 100049 People's Republic of China Grassland Research Institute Inner Mongolia Academy of Agricultural & Animal Husbandry SciencesHuhehot 010031 People's Republic of China College of Land and Environment Shenyang Agricultural University Shenyang 110866 People's Republic of China

Global change will lead to increases in regional precipitation and nitrogen（N） deposition in the semi-arid grasslands of northern China. We investigated the responses of vegetation carbon（C） pools to simulated precipitation and N deposition increases through field experiments in a typical steppe in Inner Mongolia. The treatments included NH4NO3 addition at concentrations of 0（CK）, 5（LN, low nitrogen）, 10（middle nitrogen, MN）, and 20（HN,high nitrogen）（g m^（-2）a^（-1）） with and without water. After three consecutive years of treatment, from 2010 to 2012,water addition did not significantly change the size of the total vegetation C pools, but it significantly decreased the ratio of root：shoot（R：S）（P = 0.05） relative to controls. By contrast, N addition significantly increased the total vegetation C pools. The C pools in the LN, MN and HN treatments increased by 22, 39 and 44 %, respectively. MN produced the largest effect among the N concentrations,although differences between N-added treatments were not significant（P ？ 0.05）. N addition significantly reduced the ratio of root：shoot（R：S）（P = 0.03）. However, there were no significant interactive effects of water and N addition on the vegetation C pools.

关键词： Vegetationprecipitation NitrogenTemperate steppecarbon pools Increasingaddition Interactive effect

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Influences of drip and flood irrigation on soil carbon dioxide emission and soil carbon sequestration of maize cropland in the North China Plain

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Journal of Arid Land 2017年第2期9卷 222-233页

作者： guo shufang QI Yuchun PENG Qin DONG Yunshe HE Yunlong YAN Zhongqing WANG Liqin Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

The need is pressing to investigate soil CO2 （carbon dioxide） emissions and soil organic carbon dynamics under water-saving irrigation practices in agricultural systems for exploring the potentials of soil carbon sequestration. A field experiment was conducted to compare the influences of drip irrigation （DI） and flood irrigation （FI） on soil organic carbon dynamics and the spatial and temporal variations in CO2 emissions during the summer maize growing season in the North China Plain using the static closed chamber method. The mean CO2 efflux over the growing season was larger under DI than that under FI. The cumulative CO2 emissions at the field scale were 1959.10 and 1759.12 g/m2 under DI and FI, respectively. The cumulative CO2 emission on plant rows （OR） was larger than that between plant rows （BR） under FI, and the cumulative CO2 emission on the irrigation pipes （OP） was larger than that between irrigation pipes （BP） under DI. The cumulative CO2 emissions of OP, BP and bare area （BA） under DI were larger than those of OR, BR and BA under FI, respectively. Additionally, DI promoted root respiration more effectively than FI did. The average proportion of root respiration contributing to the soil CO2 emissions of OP under DI was larger than that of OR under FI. A general conclusion drawn from this study is that soil CO2 emission was significantly influenced by the soil water content, soil temperature and air temperature under both DI and FI. Larger concentrations of dissolved organic carbon （DOC）, microbial biomass carbon （MBC） and total organic carbon （TOC） were observed under FI than those under DI. The observed high concentrations （DOC, MBC, and TOC） under FI might be resulted from the irrigation-associated soil saturation that in turn inhibited microbial activity and lowered decomposition rate of soil organic matter. However, DI increased the soil organic matter quality （the ratio of MBC to TOC） at the depth of 10-20 cm compared with FI. Our results suggest that the transformation from conventional FI to i

关键词： drip irrigation flood irrigation spatio-temporal variation carbon dioxide soil organic carbon North China Plain

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儿童血液肿瘤专科护士的职业压力调适能力及影响因素研究

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中国当代医药 2022年第11期29卷 117-119,123页

作者：黄颖郭书芳福建省儿童医院内分泌血液肿瘤科福建福州350001 河南省儿童医院郑州儿童医院血液肿瘤科河南郑州450000

目的调查儿童血液肿瘤专科护士的职业压力调适能力,探讨其影响因素。方法采用随机数字表法选取2020年1月至12月福建省儿童医院的40名儿童血液肿瘤专科护士作为研究对象,采用逆境商数(AQ)量表、中国护士工作压力源量表评估护士职业压力... 详细信息

目的调查儿童血液肿瘤专科护士的职业压力调适能力,探讨其影响因素。方法采用随机数字表法选取2020年1月至12月福建省儿童医院的40名儿童血液肿瘤专科护士作为研究对象,采用逆境商数(AQ)量表、中国护士工作压力源量表评估护士职业压力水平以及调适能力,分析其影响因素。结果40名护士压力水平量表平均(95.53±8.95)分,压力调适能力平均(16.51±1.85)分。其中应对困难者15例(37.50%),应对适度者20例(50.0%),应对自如者5例(12.50%)。单因素结果显示,不同性别、年龄、聘用方式的儿童血液肿瘤科护士的职业压力调适能力比较,差异无统计意义(P>0.05);不同学历、护龄、职称的儿童血液肿瘤科护士的职业压力调适能力比较,差异有统计意义(P<0.05)。多因素分析结果显示,低学历(β=1.973,OR=5.457,95%CI=6.313~8.493)、低护龄(β=1.495,OR=6.791,95%CI=6.312~7.326)、低职称(β=1.213,OR=5.457,95%CI=4.698~7.132)是儿童血液肿瘤科护士职业压力调适能力的独立危险因素(P<0.05)。结论儿童血液肿瘤专科护士普遍压力来源于社会因素、职业因素、专科技术压力、专科患儿特殊性等,通常护士护龄越高、学历越高,职业压力调适能力越好。

关键词：职业压力调适能力影响因素儿童血液肿瘤专科护士

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以跨学科间性融合视角看翻译与城市研究:以《劳特利奇翻译与城市指南》(2021)为例

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语言教育 2023年第3期11卷 113-123页

作者：焦鹏帅郭淑芳西南民族大学外国语言文学学院四川成都

本文针对翻译与城市的间性关系问题,以《劳特利奇翻译与城市指南》(2021)为例,深入分析其框架思路、理论渊源、视角内容和特色启示,通过对表层语言与符号,底层社会、文化、政治、历史、宗教、移民、身份等问题的剖析,指出翻译与城市的... 详细信息

本文针对翻译与城市的间性关系问题,以《劳特利奇翻译与城市指南》(2021)为例,深入分析其框架思路、理论渊源、视角内容和特色启示,通过对表层语言与符号,底层社会、文化、政治、历史、宗教、移民、身份等问题的剖析,指出翻译与城市的间性问题融合演变成一个立体、多维、复杂的跨学科问题。文章将城市中所涉学科的研究对象或现象比拟为语言、文本、符号,通过翻译去管窥,可产生对被研究对象和现象的新认知;通过城市研究中的其他学科理论、方法和视角去反观翻译,同样会催生对翻译的新认知和新知识。该文集超越文本、立于实践、特色驱动、跨科赋能的研究范式和理路可为国内翻译研究的跨学科发展提供新的理论、方法和视角,适合翻译研究、文化研究、社会学研究等领域的专业人士阅读与参考。

关键词：翻译研究城市跨学科间性融合跨学科赋能

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PBL教学法在内科护理教学中的应用现状

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现代临床护理 2013年第6期12卷 76-79页

作者：郭淑芳延安大学医学院护理系陕西延安716000

以问题为基础的学习（problem-based learning,PBL）教学模式1969年由美国神经病学教授Barrows在加拿大的麦克马斯特大学首创,在20世纪80年代引入中国[1]。其模式以临床问题为切入点,在培养学生分析、解决问题能力。

关键词： PBL教学法内科护理学护理教育

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医院感染控制中存在的护理管理问题及应对方案

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中国社区医师 2018年第31期34卷 131-132页

作者：郭树芳东营市河口区人民医院山东257200

目的:探讨医院感染控制中存在的护理管理问题及应对方案。方法:收治住院患者280例,随机分为两组,每组各140例。对照组给予常规护理管理,观察组在对照组基础上给予感染防控护理管理,比较两组护理质量、医院感染发生率以及护理满意度。结... 详细信息

目的:探讨医院感染控制中存在的护理管理问题及应对方案。方法:收治住院患者280例,随机分为两组,每组各140例。对照组给予常规护理管理,观察组在对照组基础上给予感染防控护理管理,比较两组护理质量、医院感染发生率以及护理满意度。结果:观察组护理质控评分及护理满意度明显高于对照组,医院感染发生率、护理差错发生率及护理纠纷发生率明显低于对照组,差异有统计学意义(P<0.05)。结论:医院感染控制中加强护理管理、实施防控感染措施有助于降低医院感染发生率,提升护理质量。

关键词：医院感染控制护理管理护理问题应对方案

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稻作旱种在陕西关中地区的发展前景

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西北农林科技大学学报(自然科学版) 1987年第1期 70-75页

作者：郭树芳陕西省农林学校

本文介绍了稻作旱种近年来在国内外的发展动态。阐述了稻作旱种的特点以及在陕西关中地区发展稻作旱种的可行性和广泛的发展前景。

关键词：稻作旱作陕西关中地区

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