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Changes in Organic Carbon Index of Grey Desert Soil in Northwest China After Long-Term Fertilization

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Journal of Integrative Agriculture 2014年第3期13卷 554-561页

作者： xu yong-mei LIU Hua WANG Xi-he xu Ming-gang ZHANG Wen-ju JIANG Gui-ying Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Key Laboratory of Oasis Nutrients and Efficient Utilization of Water and Soil Resources Research Institute of Soil & Fertilizer and Agricultural Water Conservation Xinjiang Academy of Agricultural Sciences

Soil organic carbon （SOC）, soil microbial biomass carbon （SMBC） and SMBC quotient （SMBC/SOC, qSMBC） are key indexes of soil biological fertility because of the relationship to soil nutrition supply capacity. Yet it remains unknown how these three indexes change, which limits our understanding about how soil respond to different fertilization practices. Based on a 22-yr （1990-2011） long-term fertilization experiment in northwest China, we investigated the dynamics of SMBC and qSMBC during the growing period of winter wheat, the relationships between the SMBC, qSMBC, soil organic carbon （SOC） concentrations, the carbon input and grain yield of wheat as well. Fertilization treatments were 1） nonfertilization （control）; 2） chemical nitrogen plus phosphate plus potassium （NPK）; 3） NPK plus animal manure （NPKM）; 4） double NPKM （hNPKM） and 5） NPK plus straw （NPKS）. Results showed that the SMBC and qSMBC were significantly different among returning, jointing, flowering and harvest stages of wheat under long-term fertilization. And the largest values were observed in the flowering stage. Values for SMBC and qSMBC ranged from 37.5 to 106.0 mg kg1 and 0.41 to 0.61%, respectively. The mean value rank of SMBC during the whole growing period of wheat was hNPKM〉NPK_M〉NPKS〉CK〉NPK. But there were no statistically significant differences between hNPKM and NPKM, or between CK and NPK. The order for qSMBC was NPKS〉NPKM〉CK〉hNPKM〉NPK. These results indicated that NPKS significantly increased the ratio of SMBC to SOC, i.e., qSMBC, compared with NPK fertilizer or other two NPKM fertilizations. Significant linear relationships were observed between the annual carbon input and SOC （P〈0.01） or SMBC （P〈0.05）, and between the relative grain yield of wheat and the SOC content as well （P〈0.05）. But the qSMBC was not correlated with the annual carbon input. It is thus obvious that the combination of manure, straw with mineral fertilizer may be benefit to increase SOC and improve soil quality than

关键词： carbon input Haplic Calcisol long-term fertilization Quotient of soil microbial biomass carbon soil organiccarbon index

Relationship between the price of green tea and black tea of the world’s major tea countries

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Ecological Economy 2020年第2期16卷 82-89页

作者： xu yong-mei School of Economics Zhejiang Gongshang UniversityHangzhou 310018CHINA

Black tea and green tea are the most important tea in the *** this paper we analyze the relationship of the world green price and black tea *** results show that:in the world tea markets,the world black tea price and the world green tea price have no co-integration,independent of the curve *** the major green tea countries,there are co-integration relationships between China and Japan,China and Brazil,Japan and Brazil,while Vietnam has a first-order stationary *** the major black tea countries,Sri Lanka and India have no co-integration,Sri Lanka and Indonesia no co-integration,India and Indonesia no co-integration,Sri Lanka and Kenya have co-integration,India and Kenya have co-integration,Kenya and Indonesia have co-integration.

关键词： tea price green tea black tea unit root test Granger causality test co-integration test

Soil Organic Carbon Accumulation Increases Percentage of Soil Olsen-P to Total P at Two 15-Year Mono-Cropping Systems in Northern China

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Journal of Integrative Agriculture 2014年第3期13卷 597-603页

作者： SHEN Pu HE Xin-hua xu Ming-gang ZHANG Hui-min PENG Chang GAO Hong-jun LIU Hua xu yong-mei QIN Song XIAO Hou-jun Key Laboratory of Crop Nutrition and Fertilization Ministry of Agriculture/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences School of Plant Biology University of Western Australia Institute of Agricultural Resources and Environment Jilin Academy of Agricultural Sciences Institute of Soil and Fertilizer Xinjiang Academy of Agricultural Sciences Guizhou Institue of Soil and Fertilizer

Soil organic carbon （SOC） and soil Olsen-P are key soil fertility indexes but information on their relationships is limited particularly under long-term fertilization. We investigated the relationships between SOC and the percentage of soil Olsen-P to total P （PSOPTP） under six different 15-yr （1990-2004） long-term fertilizations at two cropping systems in northern China. These fertilization treatments were （1） unfertilized control （control）; （2） chemical nitrogen （N）; （3） N plus chemical P （NP）; （4） NP plus chemical potassium （NPK）; （5） NPK plus animal manure （NPKM） and （6） high NPKM （hNPKM）. Compared with their initial values in 1989 at both sites, during the 1 lth to 15th fertilization years annual mean SOC contents were significantly increased by 39.4-47.0% and 58.9-93.9% at Gongzhuling, Jilin Province, and Urumqi, Xinjiang, China, under the two NPKM fertilizations, respectively, while no significant changes under the no-P or chemical P fertilization. During the 1 lth to 15th fertilization years, annual mean PSOPTP was respectively increased by 2.6-4.2 and 5.8-14.1 times over the initial values under the two chemical P fertilizations and the two NPKM fertilizations, but was unchanged in their initial levels under the two no-P fertilizations at both sites. Over the 15-yr long-term fertilization SOC significantly positively correlated with PSOPTP （r^2=0.55-0.79, P〈0.01）. We concluded that the combination of chemical P plus manure is an effective way to promote SOC accumulation and the percentage of soil Olsen-P to total P at the two mono-cropping system sites in northern China.

关键词： long-term fertilization phosphorus availability black soil grey desert soil

Dynamics of organic carbon and nitrogen in deep soil profile and crop yields under long-term fertilization in wheat-maize cropping system

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Journal of Integrative Agriculture 2022年第3期21卷 826-839页

作者： Muhammad QASWAR LI Dong-chu HUANG Jing HAN Tian-fu Waqas AHMED Sehrish ALI Muhammad Numan KHAN Zulqarnain Haider KHAN xu yong-mei LI Qian ZHANG Hui-min WANG Bo-ren Ahmad TAUQEER National Engineering Laboratory for Improving Quality of Arable Land/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081P.R.China Key Laboratory of Industrial Ecology and Environmental Engineering School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024P.R.China National Observation Station of Qiyang Agri-Ecology System/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesQiyang 426182P.R.China Guangdong Provincial Key Laboratory for Radionuclides Pollution Control and Resources School of Environmental Science and EngineeringGuangzhou UniversityGuangzhou 510006P.R.China Agro-Environmental Protection Institute Ministry of Agriculture and Rural AffairsTianjin 300191P.R.China Institute of Soil Fertilizer and Agricultural Water ConservationXinjiang Academy of Agricultural SciencesUrumqi 830091P.R.China College of Agriculture Henan University of Science and TechnologyLuoyang 471000P.R.China School of Chemical Engineering Dalian University of TechnologyDalian 116024P.R.China

Soil organic carbon(SOC)and nitrogen(N)are two of the most important indicators for agricultural *** primary objective of this study was to investigate the changes in SOC and N in the deep soil profile(up to 100 cm)and their relationships with crop productivity under the influence of long-term(since 1990)fertilization in the wheat-maize cropping *** included CK(control),NP(inorganic N and phosphorus(P)fertilizers),NPK(inorganic N,P and potassium fertilizers),NPKM(NPK plus manure),and M(manure).Crop yield and the properties of topsoil were measured yearly from 2001 to 2009.C and N contents were measured at five different depths in 2001 and *** results showed that wheat and maize yields decreased between 2001 and 2009 under the inorganic fertilizer(NP and NPK)*** average yield between 2001 and 2009 under the NP,NPK,NPKM,and M treatments(compared with the CK treatment)increased by 38,115,383,and 381%,respectively,for wheat and 348,891,2738,and 1845%,respectively,for *** long-term fertilization treatments significantly changed coarse free particulate(cf POC),fine free particulate(ff POC),intramicroaggregate particulate(i POC),and mineral-associated(m SOC)organic carbon *** the experimental years of 2001 and 2009,soil fractions occurred in the following order for all treatments:m SOC>cf POC>i POC>ff *** fractions were higher under the manure application treatments than under the inorganic fertilization *** to the inorganic fertilization treatments,manure input enhanced the stocks of SOC and total N in the surface layer(0–20 cm)but decreased SOC and N in the deep soil layer(80–100 cm).This reveals the efficiency of manure in increasing yield productivity and decreasing risk of vertical loss of nutrients,especially N,compared to inorganic fertilization *** findings provide opportunities for understanding deep soil C and N dynamics,which could help mitigate climate change impact o

关键词： carbon stock nitrogen stock carbon fraction soil profile organic amendments long-term experiment

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中国茶产业空间分布格局及演变原因分析

农业现代化研究 2007年第3期28卷 364-366页

作者：许咏梅苏祝成浙江大学农业现代化与农村发展研究中心浙江杭州310029 浙江林学院浙江杭州310029

本文对中国茶产业的空间分布格局进行了描述,在此基础上对茶产业空间格局变化进行原因分析。分析表明,茶产业的空间分布格局及演变主要受到地理环境、农业生产结构、市场集中度、市场导向以及区域经济的影响。

关键词：茶产业空间分布格局演变

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中国茶叶在日本市场的价格竞争力研究

国际贸易问题 2007年第5期293卷 55-59页

作者：许咏梅苏祝成浙江大学农业现代化与农村发展研究中心浙江林学院

本文分析了中国茶叶在日本市场的价格走势,在此基础上利用LA-AIS模型对中国茶叶在日本市场的价格竞争力进行了实证分析。结果表明,在日本市场,除斯里兰卡外,中国茶叶的价格竞争力高于其他国家。中国茶叶在日本市场的策略重点是:不断改... 详细信息

本文分析了中国茶叶在日本市场的价格走势,在此基础上利用LA-AIS模型对中国茶叶在日本市场的价格竞争力进行了实证分析。结果表明,在日本市场,除斯里兰卡外,中国茶叶的价格竞争力高于其他国家。中国茶叶在日本市场的策略重点是:不断改善产品质量以符合日本市场的准入要求。

关键词：中国茶叶日本市场价格竞争力

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技术壁垒影响我国茶叶出口的实证分析

国际贸易问题 2006年第5期 86-93页

作者：许咏梅高启杰中国农业大学经济管理学院

茶叶是我国传统的出口创汇农产品,一直以来,我国茶叶出口在国际市场上占据着极其重要的地位。随着国际农产品市场的进一步开放和国际茶叶市场竞争的日益激烈,我国茶叶的出口越来越受到国外技术壁垒的影响。本文主要从实证的角度研究了... 详细信息

茶叶是我国传统的出口创汇农产品,一直以来,我国茶叶出口在国际市场上占据着极其重要的地位。随着国际农产品市场的进一步开放和国际茶叶市场竞争的日益激烈,我国茶叶的出口越来越受到国外技术壁垒的影响。本文主要从实证的角度研究了国外技术壁垒对我国茶叶出口贸易的影响,研究表明:技术壁垒是众多影响我国茶叶出口因素中的最重要的因素,并在此基础上提出了应对技术壁垒的对策。

关键词：技术壁垒茶叶出口实证分析:对策

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创新合作网络、人力资本与创新绩效关系研究

新疆师范大学学报（哲学社会科学版） 2017年第5期38卷 116-127页

作者：张勇徐艳梅彭庚中国科学院大学管理学院北京100080 新疆师范大学人事处新疆乌鲁木齐830017

文本基于个体中心网和学科整体网相结合的视角,论述合作网络与创新绩效的双向影响、人力资本对创新绩效的影响及人力资本对合作网络的影响,使用网络分析和结构方程路径进行实证分析。研究表明:合作网络的结构特征即网络规模、网络强度... 详细信息

文本基于个体中心网和学科整体网相结合的视角,论述合作网络与创新绩效的双向影响、人力资本对创新绩效的影响及人力资本对合作网络的影响,使用网络分析和结构方程路径进行实证分析。研究表明:合作网络的结构特征即网络规模、网络强度、网络异质性及中介中心性对合作创新绩效有正向影响,而对程度中心性有负向影响;总创新绩效对网络规模及中介中心性有正向影响;人力资本属性之学历、专业技术职务及学科领导职务对合作创新绩效有正向影响,而对工作年限有负向影响;工作年限、学历、专业技术职务、学科领导职务正向影响网络规模,专业技术职务、学科领导职务负向影响程度中心性,正向影响网络异质性;合作创新绩效正向影响非合作创新绩效则间接表明合作行为前提下知识溢出效应的存在。

关键词：合作网络人力资本创新绩效

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多波层位标定技术在LMD油田的应用研究

石油地球物理勘探 2010年第A01期45卷 110-113页

作者：付雷徐永梅王璐金银姬中国石油大庆钻探工程公司地球物理勘探一公司黑龙江大庆163357

多分量地震勘探技术在研究裂隙、各向异性、储层及流体预测等方面的优势逐渐凸显。本文在大庆探区LMD油田三维三分量地震资料基础上开展了纵波、转换波合成地震记录制作、层位对比以及联合属性分析等,结果表明此法可以提高解释层位标定... 详细信息

多分量地震勘探技术在研究裂隙、各向异性、储层及流体预测等方面的优势逐渐凸显。本文在大庆探区LMD油田三维三分量地震资料基础上开展了纵波、转换波合成地震记录制作、层位对比以及联合属性分析等,结果表明此法可以提高解释层位标定的准确性。

关键词：三维三分量转换波合成记录层位标定