检索结果-南通市图书馆

Preliminary Study on Biological Characteristics of Degraded Soil Ecosystems in Dry Hot Valley of the Jinsha River

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2002年第4期12卷 365-372页

作者： HEYURONG YANGWANQIN WANGKAIYUN SONGGUANGYU ChengduInstituteofBiology theChineseAcademyofSciencesChengdu610041（China） collegeofresourcesandenvironment SouthwestAgriculturalUniversityChongqing400716（China） InstituteofMountainHazardsandenvironment theChineseAcademyofSciencesandMinistryofWaterConservancyChengdu610041（China）

Distribution characteristics of soil animals, microorganisms and enzymatic activity were studied in the dry red soil and Vertisol ecosystems with different degradation degrees in the Yuanmou dry hot valley of the Jinsha River, china. Results showed that Hymenoptera, Araneae and Collembola were the dominant groups of soil animals in the plots studied. The numbers of groups and individuals and density of soil animals in the dry red soil series were higher than those in the Vertisol series, and the numbers of individuals and density of soil animals decreased with the degree of soil degradation. Bacteria dominated microbiocoenosis not only in the dry red soils but also in the Vertisols. Microbial numbers of the dry red soil series were higher than those of Vertisol series, and decreased with the degree of soil degradation. The activities of catalase, invertase, urease and alkaline phosphatase declined with the degradation degree and showed a significant decline with depth in the profiles of both the dry red soils and the Vertisols, but activities of polyphenol oxidase and acid and neutral phosphatase showed the same tendencies only in the Vertisols. It was concluded that the characteristics of soil animals, microorganisms and enzymatic activity could be used as the bio-indicators to show the degradation degree of the dry red soils and Vertisols. Correlation among these soil bio-indicators was highly significant.

关键词： degraded soil ecosystem soil enzyme soil fauna soil microbes

Uptake of Organic Phosphorus by Arbuscular Mycorrhizal Red Clover

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2002年第2期12卷 103-110页

作者： SONGYONGCHUN P.CHRISTIE DepartmentofPlantNutrition CollegeofAgriculturalResourcesandEnvironmentalSciencesChinaAgriculturalUniversityBeijing100094（China） DepartmentofagriculturalandenvironmentalScience The

The capacities of two arbuscular mycorrhizal (AM) fungi, Glomusmosseae and Glomus versiforme, to mineralize added organic P werestudied in a sterilized clacareous soil. Mycorrhizal (inoculated witheither of the AM fungi) and non-mycorrhizal red clover (Trifoliumpratense L.) plants were grown for eight weeks in pots with upperroot, central hyphal and lower soil compartments. The hyphal and soilcompartments received either organic P (as Na-phytte) or inorganic P(as KH_2PO_4) at the rate of 50 mg P kg^-1. No P was added to theroot compartments.

关键词： arbuscular mcorrhiza organic P P uptake red clover

Effect of yttrium and manganese addition on catalytic soot combustion activity and anti-high-temperature stability of CeO_(2) catalyst

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第2期42卷 334-344,I0004页

作者： Yi zhu Xingyu Liu Wei Shi Jia Li Changbing Ye Ruimei Fang Huifeng zhu Shanhu Chen Li Lan college of Chemistry Biology and environment Yuxi Normal UniversityYuxi 653100China Institute of Biology and environmental Engineering Yuxi Normal UniversityYuxi 653100China college of environment and resources Chongqing Technology and Business UniversityChongqing 400067China college of Chemistry and Chemical Engineering Jiangxi Science and Technology Normal UniversityNanchang 330013China college of Materials and Mechatronics Jiangxi Science and Technology Normal UniversityNanchang 330013China

In order to analyze the influence of the addition of yttrium and manganese on the soot combustion performance and high temperature stability of CeO_(2) catalyst,a series of Y/Mn-modified CeO_(2) catalysts were *** effects of structural properties,textural properties,oxygen vacancies,Ce^(3+),surface adsorbed oxygen species,reduction properties and desorption properties of oxygen species on the activity were analyzed by various characterization *** results of the activity test show that the addition of manganese is beneficial to enhancement of the activity,while the addition of yttrium increases the amount of reactive oxygen species,but decreases the *** aging at 700℃,the activity of the CeMn catalyst decreases most sharply,while the catalytic activity of the CeY catalyst can be maintained to a certain ***,the addition of yttrium and manganese at the same time can stabilize the *** fundamental reason is that yttrium and manganese move to the surface of the solid solution after aging,which increases the reduction performance of the catalyst,thus contributing to the increase of *** the activity of CeYMn catalyst decreases after aging at 800℃,it is still higher than that of other catalysts aged at 700℃.

关键词： CeO_(2)catalyst Soot catalytic combustion Diesel pollution control Rare earths High temperature stability Low temperature reduction performance

在线全文

学校读者我要写书评

暂无评论

酸性土壤在改良条件下磷的吸附解吸特性

土壤学报 2004年第4期41卷 636-640页

作者：雷宏军朱端卫刘鑫周文兵洪丽芳华中农业大学资源与环境学院武汉430070 云南省农业科学院土壤肥料研究所昆明650231

在可变电荷土壤上,植物生长期间对磷肥的利用效率很低[1,2],这是由P的专性吸附所决定[3,4].Easterwood和Sarfain[5]报道了减少土壤对P素固定的磷肥与有机质配合施用技术.无机磷肥与有机肥配合施用,植物能有效地吸收肥料中的磷,其原因可... 详细信息

在可变电荷土壤上,植物生长期间对磷肥的利用效率很低[1,2],这是由P的专性吸附所决定[3,4].Easterwood和Sarfain[5]报道了减少土壤对P素固定的磷肥与有机质配合施用技术.无机磷肥与有机肥配合施用,植物能有效地吸收肥料中的磷,其原因可能是降低了土壤对磷的吸附能力,进而提高了土壤溶液中磷的浓度[6～8].相反,Li等[9]发现,施用含磷低的有机质降低了土壤磷的活性.石灰物质能有效缓解土壤的酸化.然而,对酸性土壤在同时施用石灰物质和有机物质的情况下,土壤对磷的吸附-解吸特性的研究少见报道,更重要的是此类问题与酸性土壤的改良关系密切.为此,笔者以云南赤红壤、黄红壤及湖北棕红壤为供试材料,对酸性土壤及其在施用石灰物质和玉米秸秆条件下磷的吸附解吸行为进行研究,为在此类土壤上合理施用石灰物质提供理论依据.……

关键词：酸性土壤土壤改良磷素吸附特性解吸特性石灰物质玉米秸秆

Soil Macropore Structure Characterized by X-Ray Computed Tomography

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2003年第4期13卷 289-298页

作者： FENGJie ZHANGJia-Bao zhuAn-Ning BIJing-Wei InstituteofSoilScience theChineseAcademyofSciencesNanjing210008China collegeofWaterresourcesandenvironment HohaiUniversityNanjing2100g8China

Undisturbed soil core with many macropores and disturbed soil core with onlyone macropore (diameter is 10 mm) were probed by X-ray computed tomography (CT). The size, number,shape and continuity of macropores in the transverse and vertical sectionsof soil were characterizedusing CT scanning images. The probability densities of macropores in the transverse section of soilcore exhibited a logarithmic P distribution. Results indicated that CT scanning was a promisingnondestructive method for characterizing macropores in soils.

关键词： CT scanning distribution image macropores

The Production of Organic-Inorganic Compound Film-Coated Urea and the Characteristics of Its Nutrient Release

在线全文

学校读者我要写书评

暂无评论

agricultural Sciences in china 2009年第6期8卷 703-708页

作者： ZOU Hong-tao, WANG Yao-sheng, SONG Hao-wen, HAN Yan-yu, YU Na, ZHANG Yu-ling, DANG Xiu-li, HUANG Yi and ZHANG Yu-long college of Land and environmental Sciences, Shenyang agricultural university/Liaoning Key Laboratory of agricultural resources and environment/Northeast Key Laboratory of Soil and environment, Ministry of Agriculture, Shenyang 110161, P.R.china college of Land and environmental Sciences Shenyang Agricultural University/Liaoning Key Laboratory of Agricultural Resources and Environment/Northeast Key Laboratory of Soil and Environment Ministry of Agriculture Shenyang 110161 P.R. China

The effect of different concentrations of natural macromolecular compound on the characteristics of nutrient release in the membrane materials of organic-inorganic compound film-coated urea was discussed, and the optimal concentrations for better nutrient release was proposed. The characteristics of nutrient release of film-coated urea were evaluated by soil column leaching experiment. Organic-inorganic compound film-coated urea showed good characteristics of nutrient release, which could be well simulated by Logistic curve. The two parameters in this curve, a and r, can be used to present nutrient release of film-coated urea, and followed the order of B 〉 C 〉 A and C 〈 B 〈 A, respectively, indicating that the release was stronger with the increasing concentration of natural macromolecular compound in the membrane, which implied better controllability of nutrient release. The concentration of 5% of natural macromolecular compound showed better characteristic of nutrient release and can be utilized as a membrane material combined with inorganic mineral powders to develop film-coated slow-release fertilizer.

关键词： organic-inorganic compound film-coated urea nutrient release characteristics

The CropGPT project:Call for a global,coordinated effort in precision design breeding driven by Al using biological big data

在线全文

学校读者我要写书评

暂无评论

Molecular Plant 2024年第2期17卷 215-218页

作者： Wanchao zhu Rui Han Xiaoyang Shang Tao Zhou Chengyong Liang Xiaomeng Qin Hong Chen Zaiwen Feng Hongwei Zhang Xingming Fan Weifu Li lin Li National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhan 430070China Key Laboratory of Biology and Genetic Improvement of Maize in Arid Area of Northwest Region College of AgronomyNorthwest A&F UniversityYanglingShaanxi712100China college of Informatics Huazhong Agricultural UniversityWuhan 430070China State Key Laboratory of Crop Gene resources and Breeding Institute of Crop ScienceChinese Academy of Agricultural SciencesBeijing 100081China institute of Food Crops Sciences Yunnan Academy of Agricultural Sciences2238 Beijing RoadKunmingYunnan 650200China Hubei Hongshan Laboratory Wuhan 430070China Shenzhen Institute of Nutrition and Health Huazhong Agricultural UniversityWuhan 430070China Shenzhen Branch Guangdong Laboratory for Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of AgricultureAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518120China

Since the beginning of humanity,people have been seeking practical solutions to meet their most basic need:*** advent of agriculture greatly increased the food supply and led to a rapid increase in the human *** food production via agriculture can be attributed to both improved crop management practices and crop breeding through ***(crop)breeding has been categorized into four major stages based on the techniques employed(Wallace et al.,2018).

关键词： breeding seeking Wallace

Applying a GIS-based model to collect information on agricultural land-use change in Beijing

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Applying a GIS-based model to collect information on agricul...

A Correlation Analysis of Tourism Based on Gray Theory——A case of Xingwen County

The First International Conference on Computers and Computing Technologies in Agriculture

作者： XIAOGANG CUI~(1 2) TAILAI YAN~1 DEHAI zhu~(1 2) FANGQU NIU~(1 2) XIAODONG ZHANG~(1 2 *) 1.college of Information and Electronic Engineering china agricultural university Beijing 100083 PR china 2 college of Resource and environment china agricultural university Beijing 100094 PR china

＜正＞agricultural land use in suburban Beijing has changed dramatically in the last decade. This paper utilised unique,county-level spatial inventory datasets of land use in 1993 and 2004 to better quantify spatial configuration changes of main agricultural land-use types in the suburban counties of Beijing.A revised centroid model was applied to explicitly capture,analyse and visualise centroidal coordinates of land-use types in six typical suburban counties（samples） by geographic information system（GIS）.Obvious displacements of corresponding centroids of agricultural land-use types in the samples demonstrates that configurations of agricultural land use have been destroyed in different parts of suburban ***, some typical patterns are explored according to the direction of displacement,which is driven mainly by urbanisation,topography,economic development and land-use ***-use policies are shown to play more direct roles in spatial configuration changes of agricultural land use than other factors. It can be concluded that agricultural land-use configuration in suburban Beijing is affected by land resource balance among economic development, grain production and ecological protection.

关键词： agricultural land use centroid model GIS spatial configuration suburban Beijing

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

四川地质学报 2009年第S1期29卷 133-139页

作者： WEI Ya-li 1,HUI Wei 2,WANG Li-guo 3(1.college of resources and environment,Sichuan agricultural university,Yaan,Sichuan 625014,2Agronomy college,Sichuan agricultural university,Yaan,Sichuan 625014,3college of land environment science,Jiangxi agricultural university,Nanchang,Jiangxi 330045)

Tourism industry has already become an important part of national economy,which not only played a positive role in the development of the economy,but promoted the adjustment and optimization of industrial *** paper analyzes the correlation between the tourism industry and the other industry through changes of the Xingwen County tourism industrial output value in the past seven *** the Gray Model,the correlation degree among the tourism industry and agriculture,industry,transport,wholesale and retail trade,postal and telecommunications industries is *** analysis result indicates that the order of the corresponding correlation degree:catering accommodation is 0.691> wholesale and retail is 0.617 > agriculture is 0.616 > Postal and telecommunications industry is 0.610> Transport is 0.602> Industry is *** accordance with the actual conditions of the industry in Xingwen,the industrial development policies and measures are put forward,which help the tourism industry Xingwen their rapid,coordinated and highly efficient operation.

关键词： Tourism industry Enterprise Relationship Gray relational model Correlation degree.