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Bacterial Communities in a Buried Ancient Paddy Soil from the Neolithic Age

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Pedosphere 2010年第3期20卷 389-398页

作者： SHEN Wei-Shou YIN Rui LIN Xian-Gui CAO Zhi-Hong State key laboratory of Soil and Sustainable agriculture Institute of Soil Science Chinese Academy of SciencesNanjing 210008 (China) College of Chemistry and environmental Science Nanjing Normal University Nanjing 210097 (China) Joint Open laboratory of Soil and environment Institute of Soil Science Chinese Academy of Sciences and Hong KongBaptist University Nanjing 210008 (China)

An ancient irrigated paddy soil from the Neolithic age was excavated at Chuodunshan Site in the Yangtze River Delta, close to Suzhou, china. The soil organic matter (SOM) content in the prehistoric rice soil is comparable to the average SOM content of present rice soils in this region, but it is about 5 times higher than that in the parent materials. As possible biomarkers to indicate the presence of the prehistoric paddy soil, the bacterial communities were investigated using the techniques of aerobic and anaerobic oligotrophic bacteria enumeration, Biolog analysis, and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). The results showed that in the buried soil layers, the prehistoric paddy soil had the largest number of aerobic and anaerobic oligotrophic bacteria, up to 6.12 and 5.86 log cfu g-1 dry soil, respectively. The prehistoric paddy soil displayed better carbon utilization potential and higher functional diversity compared to the parent materials and a prehistoric loess layer. The Shannon index and richness based on DGGE profiles of bacterial 16S rRNA genes were higher in prehistoric paddy soil than those in the prehistoric loess soil. It might be concluded that the prehistoric irrigated rice cultivation accumulated the SOM in plowed soil layer, and thus increased soil bacterial populations, metabolic activity, functional diversity and genetic diversity. Bacterial communities might be considered as the sensitive indicators of the presence of the prehistoric paddy soil in china's Yangtze River Delta.

关键词： biomarker denaturing gradient gel electrophoresis oligotrophic bacteria paleosols prehistoric paddy soil

Identification of antixenosis and antibiosis in two newly explored brown planthopper-resistance rice lines

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Identification of antixenosis and antibiosis in two newly ex...

第十三届全国植物基因组学大会

作者： Qiu Yongfu~1,Cheng Ling~2,Liu Fang~1,Li Rongbai~(1*) 1 State key laboratory for Conservation and Utilization of subtropical Agro-bioresources, agricultural College,Guangxi university,Nanning,530005,china 2 Engineering Research Center of Wetland agriculture in the Central Yangtze,ministry of Education,Yangtze university,Jingzhou,434025,china

The rice brown planthopper(Nilaparvata lugens Stal,BPH) is one of the typical piercing-sucking insect pests to feed on rice phloem *** studies have shown that breeding and cultivation of resistant rice varieties is the most economical and efficient method for managing the BPH,therefore it is imperative to explore and identify BPH resistance rice lines from diverse sources and incorporate the

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Surface Morphology of Soil Cracks in Yuanmou Dry-hot Valley Region,Southwest china

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Journal of Mountain Science 2009年第4期6卷 373-379页

作者： XIONG Donghong LONG Yi YAN Dongchun LU Xiaoning JI Zhonghua FANG Haidong key laboratory of Mountain Hazards and Surface Process CAS Chengdu 610041 Sichuan China Institute of Mountain Hazards and environment CAS Chengdu 610041 Sichuan China Department of environmental Engineering Chengdu University of Information Technology Chengdu 610225 Sichuan China Institute for Tropical Eco-agricultural Sciences Yunnan Academy of Agriculture Sciences Yuanmou 651300 Yunnan China

Surface morphology of soil cracks is one of the important factors influencing the water evaporation rate in cracked soil in Yuanmou Dry-hot Valley Region,Southwest china. Quantitative study of the complicated surface morphology of soil cracks is a prerequisite for further studies of soil-cracking mechanisms. The present paper establishes a quantitative indicator system by application of concepts and methods originating from Fractal Geometry and Network Analysis. These indicators can effectively express the complicated features of soil-crack network structure. Furthermore,a series of values related to soil-crack morphology was obtained by image processing on field photos of soil-crack quads,and gradation criteria for the degree of development of soil cracks were determined. Finally,the changes in values of the morphological indicators under different degrees of development were analyzed in detail. Our results indicate that (1) the degree of development of soil cracks can be divided into five grades,i.e.,feeble development,slight development,medium development,intensive development and extremely intensive development; (2) the values of the indicators change predictably with increasing degree of development of soil cracks. The area density (Dc) increases,and both the area-weighted mean ratio of crack area to perimeter (AWMARP),which reflects the intensity of cracking,and the index r,which is related to the connectivity of a soil crack,grow uniformly (albeit with different forms). AWMRAP increases at a geometric rate while r shows logarithm-mic growth,indicating a gradual increase in theconnectivity of a soil crack. Nevertheless,the area-weighted mean of soil-crack fractal dimension (AWMFRAC) shows a decreasing trend,indicating a gradual decline in the complexity of cracks as area density increases.

关键词： Soil crack Surface morphology Quantitative indicator Degree of development Southwest china

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农药污染土壤的微生物修复研究进展

土壤 2004年第6期36卷 577-583页

作者：李顺鹏蒋建东南京农业大学农业部农业环微生物工程重点开放实验室南京210095

本文介绍了土壤中农药污染的现状与危害,总结了土壤农药污染的微生物修复的历史背景、研究现状,重点介绍了降解农药的微生物与农药污染土壤微生物修复的研究进展,并总结了国内外微生物修复的产业化现状,对土壤农药污染微生物修复进行了... 详细信息

本文介绍了土壤中农药污染的现状与危害,总结了土壤农药污染的微生物修复的历史背景、研究现状,重点介绍了降解农药的微生物与农药污染土壤微生物修复的研究进展,并总结了国内外微生物修复的产业化现状,对土壤农药污染微生物修复进行了预测和展望,指出了需要进一步研究的领域。

关键词：微生物修复农药污染土壤研究进展

Propagation Characteristics of 2.4GHz Wireless Channel in Cornfields

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Propagation Characteristics of 2.4GHz Wireless Channel in Co...

2011 IEEE 13th International Conference on Communication Technology(ICCT 2011)

作者： Siyu Li Hongju Gao key laboratory of Modern Precision agriculture System Integration Research ministry of Education College of Information and Electrical Engineering china agricultural university Beijing 100083

Researches on propagation characteristics of wireless channel in cropland environments will lay the foundation for network deployments of wireless sensor network （WSN） for agricultural information *** this study,cropland with corn in maturity stage was selected as the representative of worst-case scenarios for radio propagation within cropland,and the propagation mechanisms and the impact factors on the propagation characteristics of wireless channel in this environment were *** addition,the power strength Radio Signal Strength Indicator （RSSI） and Packet Loss Rate （PLR） were measured in cornfields,and the node’s coverage was further *** experimental results were analyzed to provide the guidance and suggestion for the WSN *** the engineering practice,the nodes shall be placed in open area such as wide walkways when it is possible in order to minimize propagation loss and increase the node’s coverage *** the antenna height of 1.4m to 1.6m is a good option,which will be more economic and ***,experimental results also verified that rainfall doesn’t have much effect on the propagation of 2.4GHz wireless *** although raising the transmitted power can increase the transmission range significantly,both the power usage of battery and the radio surveillance regulations have to be taken into account.

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Isolation and Characterization of Three Sphingobium *** Capable to Degrade Phenylurea Herbicide Isoproturon

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Isolation and Characterization of Three Sphingobium *** Capa...

第十次全国环境微生物学术研讨会

作者： Sun Jiquan Huang Xing Li Shunpeng key Lab of Microbiological Engineering of agricultural environment,ministry of agriculture,College of Life Science,Nanjing agricultural university,Nanjing,P.R.of china

Three strains of bacteria (designated as YBL1,YBL2,YBL3 respectively) capable to degrade isoproturon,3-(4-isopropylphenyi)-1,1-dimethylurea (IPU),were isolated from sludge collected from the herbicide *** on partial analysis of the 16S rRNA gene,and Phenotypic and biochemical characterization,these strains were identified as Sphingobium *** of these strains, Sphingobium ***2,at inoculation quantity of 10 cells per liter was able to degrade 30 mg.L IPU provided as a sole source of carbon,nitrogen,and energy within 24 hours in mineral salt *** optimum condition for IPU degradation by these strains was pH 7.0,and temperature 30℃.The Mg (1 mmol·L) could enhance the IPU degradation rate,but Ni,Cu (1 mmol·L) inhibit IPU degradation *** three strains could remove the residue of the other phenylurea herbicide such as chlorotoluron and diuron in mineral salt medium and in the Magan *** soil pH was the most important factor for the degradation by these *** N-demethylation was the first step of degradation of dimethylurea-substituted herbicides isoproturon and *** these strains were also found capable of degrading Propail.

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Effects of Lactosucrose on intestinal barrier in TNBS-lnduced Colitis in Rats

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Effects of Lactosucrose on intestinal barrier in TNBS-lnduce...

生猪优质健康养殖关键技术国际学术研讨会

作者： Z Ruan~1 YLYin~(*1 2) GY Wu~2 (State key laboratory of Food Science and Technology Nanchang university Nanchang 330047 china Institute of subtropical agriculture the Chinese Academy of Sciences Changsha 410125 china)

＜正＞To investigate the effects of Lactosucrose on intestinal barrier in TNBS-Induced *** Lactosucrose were administered rats with experimental ulcerative colitis induced by 2,4,6-trinitrobenzene sulfonic acid（TNBS）.The colon structure was observed hematoxylin-eosin ***,a kind of tight junction protein,were determined by immunohistochemical *** mRNA expression was assessed by reverse transcriptase-polymerase chain reaction（RT-PCR）.Results Lactosucrose significantly improved

关键词： Lactosucrose rats

Identifying the northernmost summer monsoon location in East Asia

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Progress in Natural Science:Materials International 2007年第7期17卷 812-820页

作者： Hu Haoran~1 Qian Weihong~(2**) (1.Institute of Plateau Meteorology,CMA,Chengdu 610071,china 2.Monsoon and environment Research Group,School of Physics,Peking university,Beijing 100871,china) [a]Institute of Plateau Meteorology CMA Chengdu China [b]Monsoon and environment Research Group School of Physics Peking University Beijing China

An integrated index which can be used to indicate the advance of subtropical summer monsoon in East Asia has been proposed in this *** index was comhined by three variables including precipitation,wind and pseudo-equivalent potential tempera- *** northernmost summer monsoon location(NSML)was identified by using this index *** was found that the NSML ex- perienced an interdecadal shift in the period 1977—1979 based on the annual index analysis from 1961 to 2001.A comparison of the NSML with other four summer monsoon indices has also been *** result showed that the NSML could well represent the interan- nual and interdecadal variability of summer monsoon precipitation in North china(beyond 35°N),while other four indices could well indi- cate the precipitation anomalies of East Asian summer monsoon along the Yangtze River valley(around 30°N).

关键词： subtropical summer monsoon northernmost location index,interdecadal variability East Asia

Contribution of Atmospheric Nitrogen Compounds to N Deposition in a Broadleaf Forest of Southern china

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Pedosphere 2007年第3期17卷 360-365页

作者： HU Zheng-Yi XU Cheng-Kai ZHOU Li-Na SUN Ben-Hua HE Yuan-Qiu ZHOU Jing CAO Zhi-Hong State key laboratory of Soil and Sustainable agriculture Institute of Soil Science Chinese Academy of SciencesNanjing 210008 （China） College of Forest Resources and environment Nanjing Forestry University Nanjing 210007 （China） College of Resources and environment Northwest Sci-Tech University of Agriculture and Forestry Yangling 712100（China）

A one-year study in a typical red soil region of southern china was conducted to determine atmospheric nitrogen (N) fluxes of typical N compounds (NH3, NH4-N, NO3-N, and NO2) and contribution of three sources (gas, rainwater, and particles) to N deposition. From July 2003 to June 2004, the total atmospheric N deposition was 70.7 kg N ha-1, with dry deposition accounting for 75% of the total deposition. Dry NH3 deposition accounted for 73% of the dry deposition and 55% of the total deposition. Moreover, NO2 contributed 11% of the dry deposition and 8% of the total deposition. Reduced N compounds (NH4+ and NH3) were the predominate contributors, accounting for 66% of the total deposition. Therefore, atmospheric N deposition should be considered when soil acidification and critical loads of atmospheric deposition on soils are estimated.

关键词： atmospheric deposition broadleaf forest nitrogen red soil soil acidification