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Effects of elevated CO_2 concentration on growth and water usage of tomato seedlings under different ammonium/nitrate ratios

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Journal of Environmental Sciences 2007年第9期19卷 1100-1107页

作者： LI Juan zhou jian-min DUAN Zeng-qiang State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China. Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China.

Increasing atmospheric CO2 concentration is generally expected to enhance photosynthesis and growth of agricultural C3 vegetable crops, and therefore results in an increase in crop yield. However, little is known about the combined effect of elevated CO2 and N species on plant growth and development. Two growth-chamber experiments were conducted to determine the effects of NH4^＋/NO3^- ratio and elevated CO2 concentration on the physiological development and water use of tomato seedlings. Tomato was grown for 45 d in containers with nutrient solutions varying in NH4^＋/NO3^- ratios and CO2 concentrations in growth chambers. Results showed that plant height, stem thickness, total dry weight, dry weight of the leaves, stems and roots, G value （total plant dry weight/seedling days）, chlorophyll content, photosynthetic rate, leaf-level and whole plant-level water use efficiency and cumulative water consumption of tomato seedlings were increased with increasing proportion of NO3- in nutrient solutions in the elevated CO2 treatment. Plant biomass, plant height, stem thickness and photosynthetic rate were 67%, 22%, 24% and 55% higher at elevated CO2 concentration than at ambient CO2 concentration, depending on the values of NH4^＋/NO3^- ratio. These results indicated that elevating CO2 concentration did not mitigate the adverse effects of 100% NH4^＋-N （in nutrient solution） on the tomato seedlings. At both CO2 levels, NH4^＋/NO3^- ratios of nutrient solutions strongly influenced almost every measure of plant performance, and nitrate-fed plants attained a greater biomass production, as compared to ammonium-fed plants. These phenomena seem to be related to the coordinated regulation of photosynthetic rate and cumulative water consumption of tomato seedlings.

关键词： CO2 enrichment NH4^+/NO3^- ratio physiological and biochemical indices growth water use tomato seedling

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Basic study on contour tracing method in softwood cell contour extraction

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Forestry Studies in China 2009年第2期11卷 127-131页

作者： zhou Xu CHANG jian-min College of Materials Science and Technology Beijing Forestry University Beijing 100083 P. R. China

The application of digital image analysis to calculate the parameters of softwood cells and to understand their microstructure is of importance in the area of basic micro-wood research such as wood anatomy. In order to obtain cell parameters, the most important part is to separate the cells from their background in an image, which is accomplished by drawing cell contours. In this study, a contour tracing method based on digital image binarization is introduced to extract the contours of softwood cells. As well, a comparison with other traditional methods is included. The results show that using this contour tracing method, clear and complete contours can be obtained, which solves the problems of traditional methods where sharp comers and turning points in an image could not be addressed.

关键词： softwood binarization contour tracing

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Stability of the Hailuogou glacier during the“9.5”Luding Earthquake:a preliminary assessment based on multi-source observations

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Journal of Mountain Science 2022年第11期19卷 3037-3050页

作者： LIU Qiao ZHANG Bo ZHAO Bo ZHONG Yan LU Xue-yuan zhou jian-min Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610299China Climate Change Impacts and Risks in the Anthropocene(C-CIA) Institute for Environmental SciencesUniversity of Geneva1205 GenevaSwitzerland Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China University of Chinese Academy of Sciences Beijing 100049China

On 5th September 2022,a magnitude Ms-6.8 earthquake occurred nearby ***,western *** stability of the glaciers in east *** close to the epicenter was widely concerned due to the strong shake triggered by the *** multi-source observations(including in-situ photographs,remote sensing datasets before and after the event),we carried out a preliminary assessment of the stability and hazard risks of the Hailuogou(HLG)*** by the earthquake,a small block of fractured ice at the lowest part of icefall *** magnitude of the coseismic ice avalanche was relatively small,which is comparable in size to most ice avalanches over the past seven years,but much less than the previous mapped largest one(03 April 2018,runout~699 m).One most recent large(runout~608 m)ice avalanche occurred between 01 and 04 September,just before the earthquake,likely unloaded large amount of ice mass and made a larger ice avalanche avoided during the earthquake ***,the momentum of collapsed snow-icerock mass could be safely unloaded over a wide and gentler-slope ice tongue area,limiting its mobility and the risk of a cascading ***-wide surface flow dynamics monitored by Sentinel-1 satellite SAR time series(12 September 2021–19 September 2022)show that HLG glacier velocity was generally consistent before and after the *** entire HLG glacier exhibited more stable than expected,with almost no abnormal features detected in its upper accumulation part,the lower ice tongue,and its lateral paraglacial *** the glacier valley has experienced remarkable downwasting and the paraglacial environment has been strongly disturbed and destabilized,we suggested that,to efficiently evaluate glacier-related cascading hazard risks,it is also necessary to systematically combine multi-source observations(e.g.,high-resolution UAV survey,radar/Lidar scan,ground investigation,monitoring and warning systems)to continuously monitor

关键词： Luding Earthquake Mt.Gongga Glacier ice/snow avalanche Cryosphere hazards

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Enhancement of Phosphorus Solubility by Humic Substances in Ferrosols

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Pedosphere 2008年第4期18卷 533-538页

作者： HUA Quan-Xian LI jian-Yun zhou jian-min WANG Huo-Yan DU Chang-Wen CHEN Xiao-Qin Zhengzhou University Zhengzhou 450001 （China） State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Zhengzhou Institute of Aeronautical Industry Management Zhengzhou 450015 （China）

An investigation was conducted to study the effect of humic substance (HS) on the phosphorus (P) solubility in acidic soil. The soil (2.5 g), HS (0, 0.5, and 2.5 g), and P as monocalcium phosphate (0.31 and 1.25 g P kg-1 soil) were mixed with 50 mL distilled water and two different sequences of adding HS and P were used. The results indicated that the P concentration in water and 0.01 mol L-1 CaCl2 solution increased with increasing amounts of humic substance. The concentrations of Fe and Al were also increased. However, Olsen P decreased with increasing amount of humic substance. Water-soluble P concentrations from P rates at 0.31 and 1.25 g P kg-1 soil in the treatment with 0.5 g (2.5 g) humic substance addition were 360% and 70% (500% and 90%) higher, respectively, than those in the treatment with no humic substance addition. P extracted by 0.01 mol L-1 CaCl2 in the treatments with 0.5 and 2.5 g humic substance addition was increased by 400% and 540%, respectively, compared with that in the treatment without humic substance at the rate of 0.31 g P kg-1 soil, while the corresponding P concentrations were increased by 80% and 90% at the rate of 1.25 g P kg-1 soil. The order of mixing humic substance and phosphate did not significantly affect desorbed P and labile P extracted with CaCl2.

关键词： aluminium Ferrosols humic substance iron phosphorus

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Long-term straw return influenced ammonium ion retention at the soil aggregate scale in an Anthrosol with rice-wheat rotations in China

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Journal of Integrative Agriculture 2022年第2期21卷 521-531页

作者： ZHANG Wen-zhao CHEN Xiao-qin WANG Huo-yan WEI Wen-xue zhou jian-min Key Laboratory of Agro-ecological Processes in Subtropical Region and Taoyuan Station of Agro-Ecology Research Institute of Subtropical AgricultureChinese Academy of SciencesChangsha 410125P.R.China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008P.R.China

Soil aggregates are an important controlling factor for the physico-chemical and biological processes such as ammonium(NH;) retention. Straw return to the field is increasingly recommended to promote soil carbon(C) sequestration and improve crop yields. However, the effects of straw return on NH;retention at soil aggregate level in agricultural soils have seldom been investigated. This study aimed to evaluate the influences of long-term straw return on NH;adsorption and fixation in microaggregates(minimize applied N fertilizer losses in rice-wheat cropping systems.

关键词： soil organic carbon microaggregates NH4+ adsorption fixation

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Kinetics of Phosphate Release from Three Phosphate-Treated Soils

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Pedosphere 2005年第4期15卷 518-525页

作者： LI Shou-Tian zhou jian-min WANG Huo-Yan DU Chang-Wen CHEN Xiao-Qin Institute of Soil Science Chinese Academy of Sciences P. O. Box 821 Nanjing 210008 （China）.

Phosphate release from three selected soils after treatments of 1.6 and 2.4 mmol L-1 P was investigated using sequential extractions and fitted using six kinetic models, including zero order (Z), first order (F), second order (S), parabolic diffusion (PD), two constant rate (TC), and Elovich type (ET) equations. The results showed that the rate of P release was initially rapid and then gradually declined with time. Also, P release increased with added P. Total P release followed the order: paddy soil with 2.4 mmol L-1 P > red soil with 2.4 mmol L-1 P > paddy soil with 1.6 mmol L-1 P > fluvo-aquic soil with 2.4 mmol L-1 P > fluvo-aquic with 1.6 mmol L-1 P > red soil with 1.6 mmol L-1 P. For the two P treatments P release from the paddy soils in the first extraction was 44.3% and 45.6% of total released P, respectively, which were higher than those from red and fluvo-aquic soils. The ratio of P release at the end of release time was 14.0% and 13.1% in the paddy soil treated with 1.6 and 2.4 mmol L-1 P, respectively, but only 5.1% and 9.2% in the red soil and 7.0% and 5.2% in the fluvo-aquic soil, respectively. Comparison of the coefficients of determination (R2) indicated that ET, TC, and PD equations could describe the P release data better than Z, F, and S equations.

关键词： fluvo-aquic soil paddy soil phosphate red soil release kinetics

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Influence of Humic Acid on Interaction of Ammonium and Potassium Ions on Clay minerals

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Pedosphere 2013年第4期23卷 493-502页

作者： ZHANG Wen-Zhao CHEN Xiao-Qin zhou jian-min LIU Dai-Huan WANG Huo-Yan DU Chang-Wen State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Key Laboratory of Agro-Ecological Processes in Subtropical Region Institue of Subtropical Agriculture Chinese Academy of Sciences

Interaction of ammonium (NH+4) and potassium (K+) is typical in field soils. However, the effects of organic matter on interaction of NH+4 and K+have not been thoroughly investigated. In this study, we examined the changes in major physicochemical properties of three clay minerals (kaolinite, illite, and montmorillonite) after humic acid (HA) coating and evaluated the influences of these changes on the interaction of NH+4 and K+on clay minerals using batch experiments. After HA coating, the cation exchange capacity (CEC) and specific surface area (SSA) of montmorillonite decreased significantly, while little decrease in CEC and SSA occurred in illite and only a slight increase in CEC was found in kaolinite. Humic acid coating significantly increased cation adsorption and preference for NH+4, and this effect was more obvious on clay minerals with a lower CEC. Results of Fourier transform infrared spectrometry analysis showed that HA coating promoted the formation of H-bonds between the adsorbed NH+4 and the organo-mineral complexes. HA coating increased cation fixation capacity on montmorillonite and kaolinite, but the opposite occurred on illite. In addition, HA coating increased the competitiveness of NH+4 on fixation sites. These results showed that HA coating affected both the nature of clay mineral surfaces and the reactions of NH+4 and K+with clay minerals, which might influence the availability of nutrient cations to plants in field soils amended with organic matter.

关键词： adsorption illite kaolinite montmorillonite organo-mineral complex

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Effect of Nitrogen Fertilizers on Movement and Transformation of Phosphorus in an Acid Soil

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Pedosphere 2005年第4期15卷 424-431页

作者： DU Zhen-Yu zhou jian-min WANG Huo-Yan DU Chang-Wen CHEN Xiao-Qin State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing210008 （China）.

The effects of two different nitrogen fertilizers （urea and NH4C1） with monocalcium phosphate （MCP） on the movement and transformation of fertilizer P in soil microsites along with soil pH changes at different distances from the fertilizer application site were studied in an incubation experiment. A highly acidic red soil （Ultisol, pH 4.57） from south China with MCP fertilizer alone or in combination with NH4C1 or urea was added to the surface of soil cylinders and packed in wax blocks. After 7 and 28 days, the extraction and analysis of each 2 mm layer from the interface of the soil and fertilizer showed that added NH4C1 or urea did not change the movement distance of fertilizer P. However, P transformation was significantly affected （P 〈 0.05）. After 7 days, at 0-8 mm distance from the fertilizer site the addition of urea significantly decreased the water-extractable P concentration; however, after 28 days the effect of N addition had disappeared. Also,at limited distances close to the fertilizer site NH4Cl application with MCP significantly increased acid-extractable P and available P, while with the addition of urea they significantly decreased. Compared with application of MCP alone,addition of urea significantly increased soil pH in fertilizer microsites, whereas the addition of NH4Cl significantly decreased soil pH.

关键词： NH4Cl P movement P transformation red soil urea

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minimum Data Set for Assessing Soil Quality in Farmland of Northeast China

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Pedosphere 2013年第5期23卷 564-576页

作者： CHEN Yu-Dong WANG Huo-Yan zhou jian-min XING Lu ZHU Bai-Shu ZHAO Yong-Cun CHEN Xiao-Qin Institute of Soil Science Chinese Academy of Science University of Chinese Academy of Sciences Southwest University College of Resources and Environment

Soil quality assessment provides a tool for agriculture managers and policy makers to gain a better understanding of how various agricultural systems affect soil resources. Soil quality of Hailun County, a typical soybean （Glycine max L. Merill） growing area located in Northeast China, was evaluated using soil quality index （SQI） methods. Each SQI was computed using a minimum data set （MDS） selected using principal components analysis （PCA） as a data reduction technique. Eight MDS indicators were selected from 20 physical and chemical soil measurements. The MDS accounted for 74.9% of the total variance in the total data set （TDS）. The SQI values for 88 soil samples were evaluated with linear scoring techniques and various weight methods. The results showed that SQI values correlated well with soybean yield （r = 0.658＊＊） when indicators in MDS were weighted by the regression coefficient computed for each yield and index. Stepwise regression between yield and principal components （PCs） indicated that available boron （AvB）, available phosphorus （AvP）, available potassium （AvK）, available iron （AvFe） and texture were the main factors limiting soybean yield. The method used to select an MDS could not only appropriately assess soil quality but also be used as a powerful tool for soil nutrient diagnosis at the regional level.

关键词： norm value principal component analysis soil quality index stepwise regression

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Effect of CO_2 Enrichment on the Growth and Nutrient Uptake of Tomato Seedlings

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Pedosphere 2007年第3期17卷 343-351页

作者： LI Juan zhou jian-min DUAN Zeng-Qiang DU Chang-Wen WANG Huo-Yan State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of SciencesNanjing 210008 （China） Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 （China）

Exposing tomato seedlings to elevated CO2 concentrations may have potentially profound impacts on the tomato yield and quality. A growth chamber experiment was designed to estimate how different nutrient concentrations influenced the effect of elevated CO2 on the growth and nutrient uptake of tomato seedlings. Tomato (Hezuo 906) was grown in pots placed in controlled growth chambers and was subjected to ambient or elevated CO2 (360 or 720μL L-1) and four nutrient solutions of different strengths (1/2-, 1/4-, 1/8-, and 1/16-strength Japan Yamazaki nutrient solutions) in a completely randomized design. The results indicated that some agricultural characteristics of the tomato seedlings such as the plant height, stem thickness, total dry and fresh weights of the leaves, stems and roots, the G value (G value = total plant dry weight/seedling age), and the seedling vigor index (seedling vigor index = stem thickness/(plant height×total plant dry weight) increased with the elevated CO2, and the increases were strongly dependent on the nutrient solution concentrations, being greater with higher nutrient solution concentrations. The elevated CO2 did not alter the ratio of root to shoot. The total N, P, K, and C absorbed from all the solutions except P in the 1/8- and 1/16-strength nutrient solutions increased in the elevated CO2 treatment. These results demonstrate that the nutrient demands of the tomato seedlings increased at elevated CO2 concentrations.

关键词： CO2 enrichment nutrient strength nutrient uptake tomato seedlings

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