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Quantitative analysis of yield and soil water balance for summer maize on the piedmont of the North China

Jingjing WANG,Feng HUANG,Baoguo LI

《农业科学与工程前沿（英文）》 2015年 第2卷 第4期   页码 295-310 doi: 10.15302/J-FASE-2015074

摘要： The North China Plain (NCP) is a major grain production area in China, but the current winter wheat-summer maize system has resulted in a large water deficit. This water-shortage necessitates the improvement of crop water productivity in the NCP. A crop water model, AquaCrop, was adopted to investigate yield and water productivity (WP) for rain-fed summer maize on the piedmont of the NCP. The data sets to calibrate and validate the model were obtained from a 3-year (2011–2013) field experiment conducted on the Yanshan piedmont of the NCP. The range of root mean square error (RMSE) between the simulated and measured biomass was 0.67–1.25 t·hm , and that of relative error (RE) was 9.4%–15.4%, the coefficient of determination ( ) ranged from 0.992 to 0.994. The RMSE between the simulated and measured soil water storage at depth of 0–100 cm ranged from 4.09 to 4.39 mm; and RE and in the range of 1.07%–1.20% and 0.880–0.997, respectively. The WP as measured by crop yield per unit evapotranspiration was 2.50–2.66 kg·m . The simulated impact of long-term climate (i.e., 1980–2010) and groundwater depth on crop yield and WP revealed that the higher yield and WP could be obtained in dry years in areas with capillary recharge from groundwater, and much lower values elsewhere. The simulation also suggested that supplementary irrigation in areas without capillary groundwater would not result in groundwater over-tapping since the precipitation can meet the water required by both maize and ecosystem, thus a beneficial outcome for both food and ecosystem security can be assured.

关键词： AquaCrop     summer maize     soil water balance     water productivity    

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Modeling radiative effects of haze on summer-time convective precipitation over North China: a case study

Xuying WANG, Bin ZHANG

《环境科学与工程前沿（英文）》 2016年 第10卷 第4期 doi: 10.1007/s11783-016-0840-3

摘要： We modeled the impact of haze radiative effects on precipitation in North China. Shortwave heating induced by haze radiative effects would reduce heavy rainfalls. Convection was the key factor that whether precipitation was enhanced or suppressed. Precipitation was often suppressed where CAPE, RH and updraft velocities were high. The impact of haze radiative effect on summertime 24-h convective precipitation over North China was investigated using WRF model (version 3.3) through model sensitivity studies between scenarios with and without aerosol radiative effects. The haze radiative effect was represented by incorporating an idealized aerosol optical profile, with AOD values around 1, derived from the aircraft measurement into the WRF shortwave scheme. We found that the shortwave heating induced by aerosol radiative effects would significantly reduce heavy rainfalls, although its effect on the post-frontal localized thunderstorm precipitation was more diverse. To capture the key factors that determine whether precipitation is enhanced or suppressed, model grids with 24-h precipitation difference between the two scenarios exceeding certain threshold (>30 mm or<-30 mm) were separated into two sets. Analyses of key meteorological variables between the enhanced and suppressed regimes suggested that atmospheric convection was the most important factor that determined whether precipitation was enhanced or suppressed during summertime over North China. The convection was stronger over places with precipitation enhancement over 30 mm. Haze weakened the convection over places with precipitation suppression exceeding 30 mm and caused less water vapor to rise to a higher level and thus further suppressed precipitation. The suppression of precipitation was often accompanied with relatively high convective available potential energy (CAPE), relative humidity (RH) and updraft velocities.

关键词： Haze     Aerosol radiative effects     Convective precipitation    

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Chemical speciation and anthropogenic sources of ambient volatile organic compounds (VOCs) during summer

LU Sihua, LIU Ying, SHAO Min, HUANG Shan

《环境科学与工程前沿（英文）》 2007年 第1卷 第2期   页码 147-152 doi: 10.1007/s11783-007-0026-0

摘要： Volatile organic compounds (VOCs) were measured at six sites in Beijing in August, 2004. Up to 148 VOC species, including C to C alkanes, C to C alkenes, C to C aromatics, and halogenated hydrocarbons, were quantified. Although the concentrations differed at the sites, the chemical compositions were similar, except for the Tongzhou site where aromatics were significantly high in the air. Based on the source profiles measured from previous studies, the source apportionment of ambient VOCs was preformed by deploying the chemical mass balance (CMB) model. The results show that urban VOCs are predominant from mobile source emissions, which contribute more than 50% of the VOCs (in mass concentrations) to ambient air at most sites. Other important sources are gasoline evaporation, painting, and solvents. The exception is at the Tongzhou site where vehicle exhaust, painting, and solvents have about equal contribution, around 35% of the ambient VOC concentration. As the receptor model is not valid for deriving the sources of reactive species, such as isoprene and 1,3-butadiene, other methodologies need to be further explored.

关键词： Beijing     exception     gasoline evaporation     August     exhaust    

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Improving water use efficiency in grain production of winter wheat and summer maize in the North China

Xiying ZHANG,Wenli QIN,Juanna XIE

《农业科学与工程前沿（英文）》 2016年 第3卷 第1期   页码 25-33 doi: 10.15302/J-FASE-2016090

摘要： Reducing irrigation water use by improving water use efficiency (WUE) in grain production is critical for the development of sustainable agriculture in the North China Plain (NCP). This article summarizes the research progresses in WUE improvement carried out at the Luancheng station located in the Northern part of NCP for the past three decades. Progresses in four aspects of yield and WUE improvement are presented, including yield and WUE improvement associated with cultivar selection, irrigation management for improving yield and WUE under limited water supply, managing root system for efficient soil water use and reducing soil evaporation by straw mulch. The results showed that annual average increase of 0.014 kg·m for winter wheat and 0.02 kg·m in WUE were observed for the past three decades, and this increase was largely associated with the improvement in harvest index related to cultivar renewal and an increase in chemical fertilizer use and soil fertility. The results also indicated that deficit irrigation for winter wheat could significantly reduce the irrigation water use, whereas the seasonal yield showed a smaller reduction rate and WUE was significantly improved. Straw mulching of summer maize using the straw from winter wheat could reduce seasonal soil evaporation by 30–40 mm. With new cultivars and improved management practices it was possible to further increase grain production without much increase in water use. Future strategies to further improve WUE are also discussed.

关键词： harvest index     cultivar selection     deficit irrigation     root water uptake     straw mulching    

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Characteristics of mass distributions of aerosol particle and its inorganic water-soluble ions in summer

ZHAO Peng, ZHU Tong, LIANG Baosheng, HU Min, KANG Ling, GONG Jicheng

《环境科学与工程前沿（英文）》 2007年 第1卷 第2期   页码 159-165 doi: 10.1007/s11783-007-0028-y

摘要： Agricultural activity is one of the most important sources of aerosol particles. To understand the mass distribution and sources of aerosol particles and their inorganic water-soluble ions in a suburb farmland of Beijing, particle samples were collected using a microorifice uniform deposit impactor (MOUDI) in the summer of 2004 in a suburb vegetable field. The distribution of the particles and their inorganic water-soluble ions in the diameter range of 0.18 18 mm were measured. The dominant fine particle ions were SO, NO, and NH. The association of day-to-day variation of the concentration of these ions with temperature, humidity, and solar radiation suggested that they are formed by the reaction of NH3 released from the vegetable field with the acid species produced from photochemical reactions. Fine particle K is likely from vegetation emission and biomass burning. Coarse particles like Ca, Mg, NO, and SO are suggested to come from the mechanical process by which the soil particle entered the atmosphere, and from the reaction of the acid species at the surface of the soil particle. The results show that fertilizer and soil are important factors determining the aerosol particle over agricultural fields, and vegetable fields in suburban Beijing contribute significantly to the aerosol particle.

关键词： diameter     atmosphere     suburban     contribute     agricultural    

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Concentrations of toxic heavy metals in ambient particulate matter in an industrial area of northeastern China

PIAO Fengyuan, SUN Xiance, LIU Shuang, YAMAUCHI Toru

《医学前沿（英文）》 2008年 第2卷 第2期   页码 207-210 doi: 10.1007/s11684-008-0040-z

摘要： This paper investigates concentrations of various heavy metals in ambient particulate matter (PM) and provide evidence for prevention from air pollution. The concentrations of heavy metal components in the PM were determined by inductively coupled plasma/Mass spectrometry (ICP/MS) from September 2000 to August 2002 in a northeast industrial city in China. Concentrations of Cd, Mn, Pb, Ni, Cr and As in the PM were 9.3, 461.9, 588.7, 69.5, 205.7 and 57.4 ng/m in the industrial area, and 5.7, 245.5, 305.0, 31.4, 58.8 and 32.5 ng/m in the main road, respectively. Concentrations of these heavy metals except Cd were significantly higher in the industrial area and main road than those in the suburban area ( < 0.05 or < 0.01). The change curves of the six heavy metal concentrations show their concentrations increased in the winter and spring, but decreased in the summer and autumn. The results indicate that concentrations of the metals in the PM are relatively high in the industrial area and main road.

关键词： summer     August     northeast industrial     September     spring    

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Detection of geosmin and 2-methylisoborneol by liquid-liquid extraction-gas chromatograph mass spectrum (LLE-GCMS) and solid phase extraction-gas chromatograph mass spectrum (SPE-GCMS)

MA Xiaoyan, CHEN Beibei, LI Qingsong, ZHANG Qiaoli, GU Guofen

《环境科学与工程前沿（英文）》 2007年 第1卷 第3期   页码 286-291 doi: 10.1007/s11783-007-0048-7

摘要： Two sample preparation methods were introduced and compared in this paper to establish a simple, quick and exact analysis of geosmin and 2-methylisoborneol. LC-18 column was employed in solid phase extraction (SPE), 1.0 mL of hexane was adopted in liquid-liquid extraction (LLE), and the extracts were analyzed by gas chromatograph mass spectrum (GCMS) in selected ion mode. Mean recoveries of SPE were low for 2-methylisoborneol (2-MIB) and geosmin (GSM) with values below 50%. For LLE, the recoveries were satisfyingly above 50% for 2-MIB and 80% for GSM. Detection limits of the LLE method were as low as 1.0 ng/L for GSM and 5.0 ng/L for 2-MIB. A year-long investigation on odor chemicals of drinking water in Shanghai demonstrated that in the summer, there was a serious odor problem induced by a high concentration of 2-MIB. The highest concentration of 152.82 ng/L appeared in July in raw water, while GSM flocculation was minimal with concentrations below odor threshold.

关键词： summer     flocculation     simple     Shanghai     spectrum    

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标题 作者 时间 类型 操作

Quantitative analysis of yield and soil water balance for summer maize on the piedmont of the North China

Jingjing WANG,Feng HUANG,Baoguo LI

期刊论文

Modeling radiative effects of haze on summer-time convective precipitation over North China: a case study

Xuying WANG, Bin ZHANG

期刊论文

Chemical speciation and anthropogenic sources of ambient volatile organic compounds (VOCs) during summer

LU Sihua, LIU Ying, SHAO Min, HUANG Shan

期刊论文

Improving water use efficiency in grain production of winter wheat and summer maize in the North China

Xiying ZHANG,Wenli QIN,Juanna XIE

期刊论文

Characteristics of mass distributions of aerosol particle and its inorganic water-soluble ions in summer

ZHAO Peng, ZHU Tong, LIANG Baosheng, HU Min, KANG Ling, GONG Jicheng

期刊论文

Concentrations of toxic heavy metals in ambient particulate matter in an industrial area of northeastern China

PIAO Fengyuan, SUN Xiance, LIU Shuang, YAMAUCHI Toru

期刊论文

Detection of geosmin and 2-methylisoborneol by liquid-liquid extraction-gas chromatograph mass spectrum (LLE-GCMS) and solid phase extraction-gas chromatograph mass spectrum (SPE-GCMS)

MA Xiaoyan, CHEN Beibei, LI Qingsong, ZHANG Qiaoli, GU Guofen

期刊论文