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Simulation and Prediction of Soil Organic Carbon Dynamics in Jiangsu Province Based on Model and GIS Techniques

2.10 International Conference on Test and Measurement (ICTM2.10)

作者： Xinyan Tang department of Mechanical engineering engineering college of Nanjing agricultural University Nanjing Jiangsu 2.0031 china

Based on Muskhelishvili’s theoretical expressions of the Saint-Venant’s problem,using the combination of Crack3D code and Ansys software,a new combination finite element method to calculate the Saint-Venant’s torsion problem including crack is *** order to illustrate its application,the numerical example for a torsion cylinder with crack are given and the numerical results are satisfactory.

关键词： combination finite element method crack cylinder torsion problem

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Journal of Integrative Agriculture 2003年第9期 67-73页

作者： SHEN Yu 1, HUANG Yao 1,2. , ZONG Liang gang 1, ZHANG Wen 1, XU Mao 3 and LIU Lin wang 3 ( 1college of Resources and environmental Sciences, Nanjing {2. University, Nanjing 2.0095, P.R.china 2.nstitute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 10002., P.R.china 3Jiangsu {2. and Forestry department, Nanjing 2.0036, P.R.china)

Based on the databases of soils, meteorology, crop production, and agricultural management, changes in the soil organic carbon (SOC) of agro ecosystems in Jiangsu Province were simulated by using a soil organic carbon model with a linkage of GIS. Four data sets of soil organic carbon measured from various field experiments in Jiangsu Province were used to validate the model. It was demonstrated that the model simulation in general agreed with the field measurements. Model simulation indicated that the SOC content in approximately 77% of the agricultural soils in Jiangsu Province has increased since the Second National Soil Survey completed in the early 1980s. Compared with the values in 1985, the SOC content in 2.00 was estimated to increase by 1.03.0 g kg 1 for the north and the coastal areas of the province, and by 3.55.0 g kg 1 for the region of Tai Lake in the south. A slight decrease (about 0.51.5 g kg 1 ) was estimated for the central region of Jiangsu Province and the Nanjing Zhenjiang hilly area. Model prediction for 2.10 A.D. under two scena rios, i.e., with 30 and 50% of the harvested crop straw incorporation, suggested that the SOC in Jiangsu Province would increase, and thus that the agricultural soils would have potential as organic carbon storage. The incorporation of crop straw into soils is of great benefit to increase soil carbon storage, consequently to benefit the control of the rise of atmospheric CO 2.concentration and to maintain the sustainable development of agriculture.

关键词： Soil Organic carbon Model GIS Jiangsu Province

UV-Vis-草酸铁络合物-H_2._2.系产生羟自由基的Fe(phen)_3^(2.)光度法测定

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分析测试学报 2002年第5期21卷 36-39页

作者：张乃东郑威哈尔滨工业大学市政与环境工程学院哈尔滨理工大学材料学院黑龙江哈尔滨150040

UV-Vis-草酸铁络合物 -H2.2.法是一种新的高级氧化工艺 ,该工艺产生的羟自由基·OH具有极强的氧化能力 ,可与水中大多数有机物迅速反应而使其降解 ;用Fe(phen)32. 光度法研究了该体系中羟自由基·OH产生的规律 ,·OH可将Fe(phen)32.(Fe2...

UV-Vis-草酸铁络合物 -H2.2.法是一种新的高级氧化工艺 ,该工艺产生的羟自由基·OH具有极强的氧化能力 ,可与水中大多数有机物迅速反应而使其降解 ;用Fe(phen)32. 光度法研究了该体系中羟自由基·OH产生的规律 ,·OH可将Fe(phen)32.(Fe2.+-菲咯啉络合物)氧化成Fe(phen)33+(Fe3 +-菲咯啉络合物),通过测定Fe(phen)32. 在508nm处吸光度的变化可间接求出·OH的生成量 ;结果表明 ,在 pH=4.0,n(Fe2.)∶n(H2.2.∶n(C2.42.)=1∶5∶10(化学计量数 )时 ,·OH的生成量最大;该分析方法具有简单。

关键词：光度法测定草酸铁络合物羟自由基过氧化氢菲咯啉 Fenton法有机物降解氧化工艺

Reduction of Chilling Injury and Ultrastructural Damage in Cherry Tomato Fruits After Hot Water Treatment

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agricultural Sciences in china 2009年第3期8卷 304-310页

作者： YANG Jing, FU Mao-run, ZHAO Yu-ying and MAO Lin-chun department of Food Science and Nutrition, college of Biosystem {2. and Food Science, Zhejiang University, Hangzhou 31002., P.R.china department of Food Science and Nutrition College of Biosystem Engineering and Food Science Zhejiang University Hangzhou 310029 P.R. China

The effects of hot water treatment in alleviating chilling injury and reducing ultrastructural damage of mature-green cherry tomatoes （Lycopersicun esculentum cv. cerasiform Alef） were investigated. Mature-green cherry tomato fruits were treated in water at 40℃ or 45℃ for 5 min or 15 min, and then stored at 5℃ for 19 days followed by ripening at 2.℃. Water treatment at 40℃ for 15 min increased tolerance of cherry tomato fruits to chilling stress, indicating as low outbreak of skin lesion, high color a＊ value, and low electrolyte leakage. Treated fruits showed typical climacteric respiration and developed normal red color with chlorophyll degradation and lycopene accumulation during ripening, while fruits without treatment failed to develop red color and suffered skin lesion. After 19 days of chilling, heated fruits showed the conversion of chloroplast to chromoplast with the disappearance of thylakoids. Mitochondria and other cell organelles were not adversely affected in treated fruits. However, ultrastructures in pericarp cells in control fruits severely damaged with extensive disorganization of cytoplasm, swelled chloroplasts, distorted and unstacked thylakoids. Chloroplast was the first and most severely impacted organelle by chilling stress. Hot water treatment （40℃ for 15 min） before storage alleviated chilling injury in cherry tomato fruits. The results suggest that chilling injury is related with the damage of cell structure under chilling stress.

关键词： cherry tomato chilling injury heat treatment ultrastructure

Spatial Distribution of Land Cover and Vegetation Activity along Topographic Gradient in an Arid River Valley, SW china

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Journal of Mountain Science 2009年第3期6卷 274-285页

作者： LIU Wen XU Xianli LUO Jiancheng SHEN Zhanfeng ZHONG Qiuhai department of Automatic Control School of Automation Beijing Institute of Technology Beijing 100081 China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Centre for Hydrology Micrometeorology and Climate Change Department of Civil and Environmental Engineering University College Cork Cork Ireland

Anthropogenic activities have become more and more important in characterizing the landscape, but their impacts are still restricted by natural environments. This paper discusses the interactions of anthropogenic activity, vegetation activity and topography through describing the spatial distribution of land cover and vegetation activity (represented by Normalized Difference Vegetation Index, NDVI) along topographic gradient in a mountainous area of southwestern china. Our results indicate that the existing landscape pattern is controlled by anthropogenic activities as well as topographic factors. Intensive anthropogenic activities mainly occur in areas with relatively low elevation, gentle and concave slopes, as these areas are easy and convenient to attain for human. Because of the destruction by human, some land cover types (mainly grassland and shrub) are only found in relatively harsher environments. This study also finds that topographic wetness index (W) used in other places only reflects runoff generation capacity, but not indicate the real spatial pattern of soil water content in this area. The relationships between NDVI and W, and NDVI and length slope factor (LSF) show that runoff and erosion have complex effects on vegetation activity. Greater values of W and LSF will lead to stronger capacity to produce runoff and transport sediment, and thereby increase soil water content and soil deposition, whereas beyond a certain threshold runoff and erosion are so strong that they would destruct vegetation growth. This study provides information needed to successfully restore native vegetation, improve land management, and promote sustainable development in mountainous areas, especially for developing regions.

关键词： Vertical distribution of land cover Anthropogenic activity Vegetation activity environmental variability china

THE SELECTIVE SPECIAL ALLELOPATHIC EFFECTS OF A-NAPHTHYLACETIC ACID ON THE GROWTH OF PHOTOSYNTHETIC BACTERIA

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THE SELECTIVE SPECIAL ALLELOPATHIC EFFECTS OF A-NAPHTHYLACET...

Phosphate Rock Fertilizer in Acid Soils: Comparing Phosphate Extraction Methods for Measuring Dissolution

中国第三届植物化感作用学术研讨会、第八届全国杂草科学大会、联合国粮农组织——中国“水稻化感作用论坛”

作者： Lan-sheng LI~*,Ying LIU,Xian-long HU department of environmental Studies and environmental engineering,college of environmental Science and engineering,Ocean University of china,Qingdao 2.6003,china

We studied the effects of a-naphthylacetic acid,a plant growth regulator,on the growth of photosynthetic bacteria(PSB).Our experimental results showed that a-naphthylacetic acid OD{(660) promoted 9%,16.1%and 2..6%of the growth of PSB with the optimal a-naphthylacetic acid concentration at 0.1,0.5,1.0 mg / L afeter inoculation 6 ***

关键词： α-naphthylacetic acid plant growth hormone growth promotion photosynthetic Bacterium(PSB) allelopathic effect

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Pedosphere 1998年第3期8卷 273-279页

作者： T. S. ANSUMANA KAWA and WANG GUANGHUO department of Soil Science and Applied Chemistry, college of Natural Resources and {2. Sciences, Zhejiang agricultural University, Hangzhou 31002. (china) (Received March 13, 1998 revised April 2., 199 department of Soil Science and Applied Chemistry College of Natural Resources and Environmental Sciences Zhejiang Agricultural University Hangzhou 310029 China

Three phosphate extraction methods were used to investigate the dissolution, availability and transformation of Kunyang phosphate rock (KPR) in two surface acid soils. Dissolution was determined by measuring the increase in the amounts of soluble and adsorbed inorganic phosphate fractions, and did not differ significantly among the three methods. Significant correlations were obtained among P fractions got by the three extraction methods. Dissolution continued until the end of the 90 day incubation period. At the end of the period, much of the applied phosphate recovered in both soils were in the Al and Fe P or in the hydroxide and bicarbonate extractable inorganic P fractions. The dissolution of KPR in the two soils was also similar: increased addition of phosphate rock resulted in decreased dissolution. The similarity in the order and extent of dissolution in the two soils was probably due to the similarity in each soil of several factors that are known to influence phosphate rock dissolution, namely low CEC, pH, P level, and base status; and high clay and free iron and aluminum oxide contents. The results suggested that KPR could be an alternative P source in the long, if not the short, term in the soils, provided that those factors influencing P availability in the soils are not limiting.

关键词： alternative source of phosphate fractionation phosphate rock

甜高粱茎秆固态发酵制取燃料乙醇过程分析与中试研究

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太阳能学报 2010年第2期31卷 257-262页

作者：耿欣李天成李十中王二强中国农业大学资源与环境学院北京100193 清华大学核能与新能源研究院北京100084

研究了甜高粱秆固态发酵生产燃料乙醇过程工艺参数的变化规律及相关性,并以此为基础进行了5m^3转鼓式固态发酵反应器中试试验。结果表明:糖份的快速消耗伴随着乙醇的大量产生,酵母分泌相关酶类使非还原糖向还原糖转化;发酵过程pH下降,... 详细信息

研究了甜高粱秆固态发酵生产燃料乙醇过程工艺参数的变化规律及相关性,并以此为基础进行了5m^3转鼓式固态发酵反应器中试试验。结果表明:糖份的快速消耗伴随着乙醇的大量产生,酵母分泌相关酶类使非还原糖向还原糖转化;发酵过程pH下降,对乙醇产生无明显抑制;搅拌可以改善传质、传热,有利于菌体的生长和发酵的进行。中试结果表明40～44h内可完成发酵。直接固态发酵与蒸馏后获得30%～40%的粗醇溶液,平均13.5～15.5kg甜高粱秆产1kg(99.5%)无水乙醇,糟渣粗蛋白含量6.94%(干基),可替代"黄储"饲料。糖利用率最高97.50%,乙醇实际收率最高94.48%。

关键词：乙醇甜高粱秆固态发酵过程参数中试试验

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西方传教士南怀仁在华活动述略

山东农业大学学报（社会科学版） 2003年第4期5卷 79-82页

作者：严雄飞雷玉明湖北工学院社会科学系湖北武汉430068 华中农业大学文法学院湖北武汉430070

主要研究西方传教士南怀仁在华二十七年的传教活动,揭示了以南怀仁为代表的西方传教士是西方殖民主义的扩张工具.并尽心竭力为西方殖民主义服务的活动实质。

关键词：西方传教士南怀仁西方殖民地