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Effects of Amino Acids Replacing Nitrate on Growth,Nitrate Accumulation,and Macroelement Concentrations in Pak-choi (Brassica chinensis L.)

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Pedosphere 2007年第5期17卷 595-600页

作者： WANG Hua-Jing WU Liang-Huan WANG Min-yan ZHU Yuan-hong TAO Qin-Nan ZHANG Fu-Suo Ministry of Education Key Laboratory of Environmental Remediation and Ecosystem Health College of Environmental and Resource Sciences Zhejiang University Hangzhou 310029 （China） College of geography and Resource Sciences Sichuan Normal University Chengdu 610066 （China） department of Crop and Soil Sciences the Pennsylvania State University （USA） College of Resources and Environment China Agricultural University Beijing 100094 （China）

A hydroponic experiment was carried out to determine the influence of replacing 20% of nitrate-N in nutrient solutions with 20 individual amino acids on growth, nitrate accumulation, and concentrations of nitrogen （N）, phosphorus （P）, and potassium （K） in pak-choi （Brassica chinensis L.） shoots. When 20% of nitrate-N was replaced with arginine （Arg） compared to the full nitrate treatment, pak-choi shoot fresh and dry weights increased significantly （P ≤ 0.05）, but when 20% of nitrate-N was replaced with alanine （Ala）, valine （Val）, leucine （Leu）, isoleucine （Ile）, proline （Pro）, phenylalanine （Phe）, methionine （Met）, aspartic acid （Asp）, glutamic acid （Glu）, lysine （Lys）, glycine （Gly）, serine （Ser）, threonine （Thr）, cysteine （Cys）, and tyrosine （Tyr）, shoot fresh and dry weights decreased significantly （P ≤ 0.05）. After replacing 20% of nitrate-N with asparagine （Asn） and glutamine （Gin）, shoot fresh and dry weights were unaffected. Compared to the full nitrate treatment, amino acid replacement treatments, except for Cys, Gly, histidine （His）, and Arg, significantly reduced （P ≤0.05） nitrate concentrations in plant shoots. Except for Cys, Leu, Pro, and Met, total N concentrations in plant tissues of the other amino acid treatments significantly increased （P ≤ 0.05）. Amino acids also affected total P and K concentrations, but the effects differed depending on individual amino acids. To improve pak-choi shoot quality, Gln and Asn, due to their insignificant effects on pak-choi growth, their significant reduction in nitrate concentrations, and their increase in macroelement content in plants, may be used to partially replace nitrate-N.

关键词： amino acids growth N P and K nitrate accumulation pak-choi

CSCO_3 CYCLES IN SALAWUSU RIVER BASINSINCE 150KA B.P.

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Chinese Geographical Science 2001年第4期11卷 50-56页

作者： LUO Kai-li1,2, LI Bao-sheng1,2, ZHU Yi-zhi2, JIN He-ling3, ZHANG David Dian4, yan Man-cun5, LI Hou-xin1, YAO Chun-xia1, ZHANG Yu-hong1f 1. department of geography, South china normal university, Guangzhou 510631, P. R. china 2. State Key Labor

ABSTRACT: This paper, with Milanggouwan stratigraphic section as a typical section of the Salawusu River Basin, explores the relation between CaCO3 content distribution and climate change since 150 ka B. P. and concludes that: 1) The low-high changes of CaCO3 content in the section has a remarkable corresponding relation with the sedimentary cycles of ancient aeolian sand and overlying fluviolacustrine facies or palaeosols. 2) CaCO3 distribution in aeolian sand is relatively meagre, ranging from 0. 8% - 7. 18%, or on an average 2. 50% but relatively enriches in the fluviolacustrine faceis and palaeosols, ranging from 2. 20% - 14. 9% , or on an average 5. 74%. This implies that they have different climatic backgrounds. The former was the product of erosion, transport and deposition by wind under arid and cold climatic conditions, whereas the latter was related to its special low-lying geomorphic position between the Ordos Plateau and Loess Plateau and warm-humid climatic environment. When the climatic became warm and humid, fluviolacustrine and swamp facies developed, soil-forming action strengthened, and low-lying catchment condition was favorable to CaCO3 accumulation. 3) The basic cause responsible for the multicycle of CaCO3 migration and accumulation in the Milanggouwan section may be the multiple alterations of winter and summer monsoons over the Mu Us Desert under the influences of climatic fluctuation of glacial and interglacial periods in the Northern Hemisphere since 150ka B. P. .

关键词： Milanggouwan section 150ka B. P. CaCO3, 27 sediment-climatic cycles

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大连市观光农业发展分析

沈阳师范大学学报（自然科学版） 2004年第4期22卷 305-308页

作者：崔红艳吉林白城师范学院地理系吉林白城137000

观光农业作为农业与旅游业相结合的新世纪阳光产业,符合现代农业与生态旅游发展的方向,在世界范围内蓬勃发展.在进行大连市发展观光农业的可行性分析基础上,提出了具体开发原则、发展对策与发展思路.

关键词：大连市观光农业发展

黑土区不同耕作措施对土壤水分和玉米产量的影响

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植物营养与肥料学报 2024年第8期30卷 1447-1460页

作者：文雪温艳茹刘宝周统高睿璐刘艳辉尧水红北方干旱半干旱耕地高效利用全国重点实验室/中国农业科学院农业资源与农业区划研究所北京100081 云南省高原地理过程与环境变化重点实验室/云南师范大学地理学部云南昆明650050 中国农业科学院农田灌溉研究所河南新乡453003 黑龙江省水利科学研究院齐齐哈尔试验站黑龙江齐齐哈尔161006

【目的】研究东北黑土区不同保护性耕作措施对土壤养分、玉米产量及水分利用的影响,为该区旱作农田耕作技术应用提供理论支持。【方法】于2019年在黑龙江省齐齐哈尔进行田间试验,设置4个耕作措施处理:1)秋季清理玉米秸秆并旋耕整地玉米... 详细信息

【目的】研究东北黑土区不同保护性耕作措施对土壤养分、玉米产量及水分利用的影响,为该区旱作农田耕作技术应用提供理论支持。【方法】于2019年在黑龙江省齐齐哈尔进行田间试验,设置4个耕作措施处理:1)秋季清理玉米秸秆并旋耕整地玉米连作(传统耕作);2)玉米饲草间作,饲草盛期刈割覆盖,秋天深翻还田(粮草间作);3)玉米单作,秸秆覆盖还田免耕(覆盖免耕);4)休耕3年后旋耕整地,次年播种玉米并传统方法整地(休耕再耕作)。3年后(2022年)于播种前取样,分析0—20 cm土层土壤养分含量和0—100 cm土层土壤容重。在玉米出苗前、苗期、抽雄期和成熟期,每20 cm为1层,分析0—100 cm土层土壤水分含量,调查玉米产量和水分利用效率。【结果】与传统耕作比,粮草间作、覆盖免耕和休耕再耕作3个耕作处理0—20 cm土壤容重显著降低,以休耕再耕作容重最低;苗前0—20 cm土层土壤储水量分别显著增加了6.36%、13.17%和23.09%,粮草间作与休耕再耕作20—100 cm土层土壤储水量显著低于传统耕作。粮草间作、覆盖免耕和休耕再耕作3个耕作处理玉米田间耗水量较传统耕作分别减少14.18%、9.26%和10.96%,水分利用效率分别提高48.51%、26.22%和42.46%,土壤有机碳含量分别增加2.24%、11.52%和15.68%。与传统耕作方式相比,粮草间作、覆盖免耕和休耕再耕作对玉米穗行数无显著影响,但显著提高玉米行粒数,因此产量分别提高27.46%、14.54%和26.87%。【结论】保护性耕作可有效提高土壤有机碳含量,增加土壤水分,减少玉米田间耗水量,显著提高玉米产量14%~28%和水分利用效率26%~49%。因此,在东北黑土区旱作农田推广保护性耕作是一种增产、节水的有效途径。

关键词：保护性耕作储水量玉米耗水水分利用效率作物产量

Environmental factors influencing the distribution of total and fecal coliform bacteria in six water storage reservoirs in the Pearl River Delta Region,china

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Journal of Environmental Sciences 2010年第5期22卷 663-668页

作者： Huachang hong Jianwen Qiu yan Liang College of geography and Environmental Sciences Zhejiang Norraal University Jinhua 321004 China Croucher Institute for Environmental Sciences and the department of Biology Hong Kong Baptist University Kowloon Tong Hong Kong China

The Pearl River Delta （PRD） is one of the most developed and densely populated regions in *** the amount of pathogens in the source of drinking water is important for improving water *** collected water samples from six major water storage reservoirs in the PRD region in both wet and dry seasons in *** showed that external environmental factors,such as precipitation,location,as well as the internal environmental factors,i.e.,physicochemical properties of the water,were closely related with the distribution of ***,the coliform bacterial concentrations in wet season were one to two orders of magnitude greater than those in dry ***,coliform bacterial levels in reservoirs near urban and industrial areas were significantly higher （p 〈 0.05） than those in remote *** analyses showed that the levels of coliforms had close relationships with pH,temperature,suspended solid,organic and inorganic nutrients in *** components analysis further demonstrated that total coliforms in the reservoirs were closely related with water physicochemical properties,while fecal coliforms were more associated with external input brought in by seasonal runoff.

关键词： coliform bacteria location rainfall physicochemical parameters reservoir

Fatty acids and algal lipids as precursors of chlorination by-products

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Journal of Environmental Sciences 2012年第11期24卷 1942-1946页

作者： yan Liang Yuen Shan Lui Huachang hong Croucher Institute for Environmental Sciences(CIES)and department of Biology Hong Kong Baptist UniversityKowloon TongHong KongChina College of geography and Environmental Sciences Zhejiang Normal UniversityJinhua 321004China Centre for Food Safety and Environmental Technology Guangzhou Institute of Advanced TechnologyChinese Academy of SciencesGuangzhou 511458China

Six common algal fatty acids （FAs） with different numbers of double bonds, lipophilic fractions and proteins extracted from the diatom Navicula pelliculosa and algal ceils were chlorinated to evaluate their potential in generating disinfection by-products （DBPs）. The result showed that the more double bonds in the FAs, the higher the amounts of chloroform and dichloroacetic acid （DCAA） produced, but such a pattern was not observed for trichloroacetic acid （TCAA）. Based on the previously reported composition of fatty acids in algal lipids, the DBP generation potentials of algal lipids were calculated. These predicted values were much lower than those measured in the chlorinated algal lipophilic fraction, suggesting unknown lipophilic fraction（s） served as potent DBPs precursors. Another calculation attempted to predict DBP production in algal cells based on algal lipid and protein composition, given quantified measured DBP production per unit algal lipid and proteins. The analysis showed that the observed DBP production was similar to that predicted （〈 35% difference）, suggesting that algal biochemical compositions may serve as a bioindicator for preliminary estimation of chloroform, DCAA and TCAA formation upon chlorinating algae.

关键词： algal lipid algal-derived organic materials chlorination by-products fatty acids

Analyzing and Forecasting Climate Change in Harbin City,Northeast china

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Chinese Geographical Science 2011年第1期21卷 65-73页

作者： ZHANG Lijuan LIU Dong yan Xiaodong ZHOU Dongying ZHENG hong SU Lianling Key Laboratory of Regional Climate-Environment Research for Temperate east Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Key Laboratory of Remote Sensing Monitoring for Geographic Environment Harbin Normal University Harbin 150025 China Heilongjiang Climate Center Harbin 150080 China department of geography Kansas State University Manhattan 66506 USA

Based on sounding data from 1975 to 2005 and TM/ETM+ remote sensing images in 1989, 2001 and 2007, the climate changes in Harbin City, Northeast china in recent 30 years were analyzed and forecasted. Results show that in the lower troposphere the meridional wind speed and mean annual wind speed decrease, and in the lower stratosphere the temperature decreases while the meridional wind speed increases significantly. In the study area, the climate is becoming warmer and wetter in the middle lower troposphere. The expansion of urban area has great effects on the surface air temperature and the wind speed, leading to the increase of the surface air temperature, the decrease of the surface wind speed, and the increase of the area of urban high temperature zone. The quantitative equations have been established among the surface air temperature, the carbon dioxide (CO2) concentration and the specific humidity (the water vapor content). It is predicted that the future increasing rate of the surface air temperature is 0.85℃/10yr if emission concentration of CO2 remains unchanged; if emission concentration of CO2 decreases to 75%, 50% and 25%, respectively, the surface air temperature will increase 0.65℃/10yr, 0.46℃/10yr and 0.27℃/10yr, respectively. The rise of the surface air temperature in the study area is higher than that of the global mean temperature forecasted by IPCC.

关键词： climate change climate forecast cause analysis Northeast china

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黄河流域资源型城市碳达峰情景模拟研究

西北师范大学学报（自然科学版） 2024年第1期60卷 106-114页

作者：施晓燕赵有益王音璠史战红甘肃农业大学理学院甘肃兰州730070 香港中文大学地理与资源管理学部中国香港999077

自然灾害与极端天气频发,各城市有效推进碳减排已刻不容缓,尤其是黄河流域的资源型城市,地区经济发展主要依赖高耗能、高排放的资源产业,使得减排降碳任务更为艰巨.本文基于黄河流域资源型城市碳排放数据,首先采用贝叶斯模型平均法进行... 详细信息

自然灾害与极端天气频发,各城市有效推进碳减排已刻不容缓,尤其是黄河流域的资源型城市,地区经济发展主要依赖高耗能、高排放的资源产业,使得减排降碳任务更为艰巨.本文基于黄河流域资源型城市碳排放数据,首先采用贝叶斯模型平均法进行因子选择,从影响碳排放的多种影响因素中提取重要信息,找出后验概率值大于50%时的几个变量作为影响碳排放的重要因素.其次,基于黄河流域资源型城市面板数据,结合情景分析法,在基准情景、政策导向型情景和科技驱动型情境下,构建个体时点双固定效应面板数据模型预测不同情境下各地区的碳排放量.结果表明:煤炭消费量、城镇化率、水泥产量、人均GDP、天然气消费量和第二产业在GDP中的比重是影响黄河流域资源型城市碳排放量的主要因素;通过比较政策导向方案和技术驱动方案,可以发现政策导向方案是一个渐进的过程,而技术驱动的碳减排效果更加快速和明显,基准情形下黄河流域资源型地区难以实现2030碳达峰目标.

关键词：资源型城市碳排放贝叶斯模型平均面板数据回归模型情景模拟

Will male semen quality improve with environmental quality?

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Asian Journal of Andrology 2023年第2期25卷 252-258页

作者： Xu-Chao Dai Meng-Qi Zhang Gang Chen Kun Mei yan-Long Liu hong Huang Zhi-Gang Wu School of Public Health and Management Wenzhou Medical UniversityWenzhou 325035China School of geography Science and Geomatics Engineering Suzhou University of Science and TechnologySuzhou 215009China School of Mental Health Wenzhou Medical UniversityWenzhou 325035China Research Center for Healthy china Wenzhou Medical UniversityWenzhou 325035China Zhejiang Provincial Key Laboratory of Watershed Sciences and Health Wenzhou 325035China department of Urology The First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000China Reproductive Health Research Center Health Assessment Center of Wenzhou Medical UniversityWenzhou 325000China

Wenzhou has improved its environmental quality because of comprehensive environmental remediation;nevertheless,the semen quality of infertile males remains *** study determined whether better environmental quality improved semen quality in this *** recorded semen quality data from 22962 infertile males from January 2014 to November 2019 at the Center for Reproductive Health of The First Affiliated Hospital of Wenzhou Medical university(Wenzhou,china).Patients were predominantly 30–35 years old(33.1%)and workers(82.0%),with high school education or lower(77.6%);more than a half of the patients(52.6%)were Wenzhou household registration;and most patients(77.5%)had abnormal semen *** who were older than 40 years and workers,and those with Wenzhou household registration,had significantly worse semen quality(all Pnormal sperm morphology showed a linearly decreasing trend(P=0.046).Sensitivity analyses for subgroups yielded similar *** conclusion,the improvement of environmental quality and better function of the accessory glands are associated with progressive sperm motility,total sperm motility,and semen *** sperm morphology is influenced by occupational exposures and personal lifestyle and does not improve with environmental quality.

关键词： environmental quality male infertility semen quality time trend