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Species and Control Techniques of Main Diseases and Insect Pests of Camellia oleifera in Anhui Province
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作者 Juanjuan HU Hao SONG +5 位作者 Zhihua CAO Yulu CHEN Jie WANG Wangsheng ZHU Dewu YAO Bangxing HAN 《Plant Diseases and Pests》 CAS 2023年第3期1-4,13,共5页
[Objectives]The paper was to master the species,incidence regularity and control techniques of main diseases and insect pests of Camellia oleifera in Anhui Province.[Methods]The species of main diseases and insect pes... [Objectives]The paper was to master the species,incidence regularity and control techniques of main diseases and insect pests of Camellia oleifera in Anhui Province.[Methods]The species of main diseases and insect pests of C.oleifera in major C.oleifera afforestation bases and seedling bases in Anhui Province were investigated through field survey and literature search.Afterwards,the symptom characteristics,occurrence regularity and harms of diseases and insect pests were analyzed,and scientific and reasonable control techniques were put forward.[Results]The main diseases of C.oleifera in Anhui Province were soft rot disease,blister blight,anthracnose,sooty blotch,etc.,and the main insect pests were Euproctis pseudoconspersa,Biston marginata,Hypomeces squamosus,Curculio chinensts,Chrenoma atritarsis,etc.The control techniques mainly included ecological regulation,physical prevention and control,chemical prevention and control,and biological prevention and control.[Conclusions]The results will promote the high-quality development of C.oleifera industry in Anhui Province,and contribute to the improvement of China s edible vegetable oil supply and national grain and oil security. 展开更多
关键词 anhui province Camellia oleifera DISEASES Insect pests Prevention and control technique
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Spatio-temporal Variations of Evapotranspiration in Anhui Province Based on MOD16 Products 被引量:1
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作者 黄飞羽 何彬方 +1 位作者 汪翔 黄洋 《Agricultural Science & Technology》 CAS 2017年第11期2092-2097,2105,共7页
Based on the MOD16 remote sensing product provided by NASA, the temporal and spatial distribution characteristics of evapotranspiration in Anhui Province from 2000 to 2014 were analyzed statistically with the support ... Based on the MOD16 remote sensing product provided by NASA, the temporal and spatial distribution characteristics of evapotranspiration in Anhui Province from 2000 to 2014 were analyzed statistically with the support of ENVI remote sensing image processing system and ARCGIS .geographic information system. The results showed that: (1) The annual average ET in Anhui Province was 694.9 mm from 2000 to 2014, less than half of PET, indicating that Anhui Province as a whole was in dry climate and water shortage, particularly significant in 2011-2014, with the maximum value of 730.6 mm occurring in 2003, and the minimum value of 647.6 mm occurring in 2011. The monthly average ET and PET showed a single peak distribution pattern, ET peak appearing in August, and PET peak appearing in May. (2) Linear regression analysis of ET and PET showed that there was a signif- icant decrease trend in ET in Anhui Province from October to March of the following year, and in addition, there was also a decreasing trend in the summer from June to July, but PET for the whole year demonstrated an increasing trend. The change trends of both illustrated that drought in Anhui Province was becoming more and more serious. (3) The spatial distribution of ET and PET showed that Anhui Province had obvious characteristics of high in south and low in north, and the north had large yearly and monthly changes, while the south had relatively stable changes. (4) The evapotranspiration of different land use types showed different an- nual and monthly variation characteristics, and the overall expression of annual evapotranspiration was in the order of forest 〉 grassland 〉 farmland. In terms of the monthly change, monthly evapotranspiration was manifested as winter grassland larger than the forest, forest evapotranspiration gradually exceeding the grass, and the evapotranspiration gap among the three widening continuously until the peak appearing in July or August. Due to the seasonality of crop plantation and under the common action of temperature, precipitation and other sensitive factors, the monthly evapotranspiration of forest and grassland was of single peak distribution with the maximum appearing in July, and the monthly evapotranspiration of farmland showed double peak distribution, appearing respectively in May and August, the former being weaker than the latter in strength 展开更多
关键词 MOD16 EvapotranspiraUon Land anhui province
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Underplating of Mesozoic Mantle-derived Magmas in Tongling, Anhui Province: Evidence from Megacrysts and Xenoliths 被引量:10
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作者 DUYangsong LEEHyunkoo QINXinlong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第1期131-136,共6页
Lithological observations and mineralogical analyses on pyroxene and hornblende megacrysts and pyroxene and hornblende cumulates in xenoliths in the Mesozoic plutons of the Tongling region, Anhui Province, provide evi... Lithological observations and mineralogical analyses on pyroxene and hornblende megacrysts and pyroxene and hornblende cumulates in xenoliths in the Mesozoic plutons of the Tongling region, Anhui Province, provide evidence for the magmatic underplating of mantle-derived alkali-olivine basalt at circa 140 Ma. The pyroxene and hornblende megacrysts and cumulates were formed through the AFC process at depths ranging from 27 to 35 km. 展开更多
关键词 magma underplating MEGACRYSTS XENOLITHS Tongling in anhui province
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Risk Assessment of Hail Disaster on Cotton——A Case Study in Anhui Province 被引量:2
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作者 尹圆圆 王静爱 +2 位作者 赵金涛 岳耀杰 马进 《Agricultural Science & Technology》 CAS 2012年第8期1744-1748,共5页
[Objective] The aim was to reveal the pattern of hail disaster risk for cotton in Anhui Province. [Method] Based on database of risk evaluation on hail disaster for cotton in Anhui Province, statistical inference and ... [Objective] The aim was to reveal the pattern of hail disaster risk for cotton in Anhui Province. [Method] Based on database of risk evaluation on hail disaster for cotton in Anhui Province, statistical inference and comprehensive indices measurement were made use of for extraction of disastrous index of hail (H) and loss rate of cotton (L). Hail vulnerability curves in four stages (seedling, bud, boll and boll opening stages) of cotton were fitted by Matlab and SPSS software. Risk evaluation on hail disaster of cotton in Anhui Province was conducted and the related map was drawn on basis of yearly model of loss rate (by hail disaster), as follows: Sa=n∑i=1Si-a∏i=1Si=1-(1-Si) [Result] In Anhui Province, high risk area by hail concentrates in northeast regions and mountainous regions in west of Anhui, and lower risk area is distributed in middle and down streams of Yangtze River and mountainous area in south of Anhui. [Conclusion] The research explored evaluation methods on hail risks based on the limited information, and could provide references for risk evaluation on hail disaster in other regions. 展开更多
关键词 anhui province Hail disaster COTTON Risk assessment
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Hamatophyton from the Late Devonian of Anhui Province,South China and Evolution of Sphenophyllales 被引量:5
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作者 WANG Deming GUO Yun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第3期492-503,共12页
Well-preserved specimens of Hamatophyton verticillatum collected from the Upper Devonian (Famennian) Wutong Formation of Chaohu district, Anhui Province, South China, display more complete fertile axes in three orde... Well-preserved specimens of Hamatophyton verticillatum collected from the Upper Devonian (Famennian) Wutong Formation of Chaohu district, Anhui Province, South China, display more complete fertile axes in three orders and multiple divisions. Comparisons indicate that Hamatophyton possibly does not have palmate planate sterile leaves but hook-like linear ones with rare divisions. We propose seven definitive characters of Sphenophyllales: (1) completely whorled lateral organs; (2) sterile leaves; (3) strobili; (4) "sporangiophores" or stalks with reflexed tips bearing sporangia; (5) three- or four-ribbed primary xylem; (6) exarch maturation of primary xylem; and (7) secondary xylem. The Sphenophyllales probably originated from the Iridopteridales based on similarities in whorled lateral organs, ribbed primary xylem and peripheral protoxylem strands. In transition from Iridopteridales to Sphenophyllales, morphological changes involve partially whorled to completely whorled lateral organs, sterile ultimate appendages to leaves, and fertile ultimate appendages to "sporangiophores"/stalks with bracts; anatomical modifications include configuration and maturation of primary xylem, and presence of secondary xylem. 展开更多
关键词 Hamatophyton Sphenophyllales Iridopteridales Sphenopsida Late Devonian WutongFormation anhui province
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The Analysis on the Temporal and Spatial Variation of Strong Precipitation Caused Flood and Agricultural Disaster Loss in Huaihe River Basin of Anhui Province during Meiyu Period of 2007 被引量:1
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作者 YU Jia-cheng1,WU Chang-chun1,HUANG Xiao-yan1,HE Yong-qing1,YU Yang2,WANG Sheng2,GUO Xiu-yun2,WANG Hua3 1.Anhui Agricultural University,Hefei 230036,China 2.Anhui Meteorological Bureau,Hefei 230061,China 3.Anhui Civil Affairs Bureau,Hefei 230061,China 《Meteorological and Environmental Research》 CAS 2011年第7期87-90,共4页
[Objective] The research aimed to analyze temporal and spatial variation of strong precipitation caused flood and agricultural disaster loss in Huaihe River basin of Anhui Province during Meiyu period of 2007.[Method]... [Objective] The research aimed to analyze temporal and spatial variation of strong precipitation caused flood and agricultural disaster loss in Huaihe River basin of Anhui Province during Meiyu period of 2007.[Method] On the basis of rainfalls of each station in Huaihe River basin of Anhui,rainfall data during Meiyu period of 2007 and flood disaster data in the same period,the temporal and spatial distribution characteristics of strong precipitation caused flood during Meiyu period of 2007 and its harm on agriculture were analyzed.The variation rule,distribution characteristics of strong precipitation during Meiyu period in Huaihe River basin of Anhui and its relationship with agricultural disaster loss were discussed.[Result] During Meiyu period of 2007 in Huaihe River basin of Anhui,the rainstorm was more,and the rainfall was large.The precipitation variation showed 'three-peak' trend.Rainfall in Huaihe River basin during Meiyu period of 2007 was greatly more than that homochronously in Yangtze River basin.The rain area over 400.0 mm during Meiyu period mainly located in Huaihe River basin,and the rain area over 600.0 mm mainly located from area along Huaihe River to central Huaibei.The rainfall during Meiyu period gradually decreased toward south and north by the north bank of Huaihe River as the symmetry axis.The rainfall in area along Huaihe River showed wavy distribution in east-west direction.The flood disaster loss index and disaster area of crops in Huaihe River basin of Anhui both increased as rainfall in Meiyu period.[Conclusion] The research provided theoretical basis for flood prevention,disaster reduction and agricultural flood-avoiding development in Huaihe River basin. 展开更多
关键词 Huaihe River basin of anhui province Meiyu period of 2007 Strong precipitation caused flood Temporal and spatial distribution Agricultural disaster loss Characteristic analysis China
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Classification and Development Laws of Karst Landform in Suzhou Area, North Anhui Province of China
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作者 马艳平 陈松 《Journal of Landscape Research》 2011年第9期92-95,共4页
Suzhou area in north Anhui Province is a low hilly area on the Huaibei Plain where carbonate rocks and karstification are widely distributed, and karst landscapes form major physical contours of the bedrock outcrops. ... Suzhou area in north Anhui Province is a low hilly area on the Huaibei Plain where carbonate rocks and karstification are widely distributed, and karst landscapes form major physical contours of the bedrock outcrops. Through field investigation, karst landscapes of Suzhou area were divided into two categories based on their morphological characteristics: macro-geomorphologic landscapes including normal hills, dry valleys, karst springs and caves, and micro-corrosion landscapes including corrosion pits, dissolved pores, dissolution traces, corrosion cracks, clints and karrens. Distribution, development and scale of karst landscapes in this region are controlled by climate, rock type, structure, topography and other factors. It was suggested that karst landscapes in the study area could be used as a representative of karst landforms in North China. 展开更多
关键词 KARST LANDFORM CLASSIFICATION Development laws KARST in NORTH China Northern anhui province
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Study on Tourism Development in Inferior Tourism Regions of Anhui Province
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作者 刘成 《Journal of Landscape Research》 2009年第5期84-89,共6页
This study aims to summarize the characteristics of 3 types of inferior tourism regions,so as to contribute to the local tourism development and provide references for the tourism development of other inferior tourism... This study aims to summarize the characteristics of 3 types of inferior tourism regions,so as to contribute to the local tourism development and provide references for the tourism development of other inferior tourism regions.With Anhui Province as an example,this study classifies different types of inferior tourism regions,and figures out the definite counties (cities) to assess their richness of tourism resources and regional development levels by utilizing SPSS and fully analyzing the data after calculating the economic development levels of these counties (cities).For I-class inferior tourism regions,regional cooperation model and brand management model should be adopted to improve their competitiveness,for II-class inferior tourism regions,poverty alleviation model should be adopted and moderate development strategy for III-class inferior tourism regions. 展开更多
关键词 INFERIOR TOURISM ZONE TOURISM in anhui province TOURISM development
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VARIATION IN FLOW AND SEDIMENT OF DASHA RIVER AND INFLUENCE OF HUMAN ACTIVITIES ON IT IN SOUTHWEST REGION OF ANHUI PROVINCE
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作者 CHEN Bao-ping ZHANG Jian-chun 《Chinese Geographical Science》 SCIE CSCD 2006年第2期109-115,共7页
Soil and water loss is now a major environmental problem in many areas of China, especially in the area of the Dabie Mountain, Anhui Province, which results in environmental degradation and does harm to the people's ... Soil and water loss is now a major environmental problem in many areas of China, especially in the area of the Dabie Mountain, Anhui Province, which results in environmental degradation and does harm to the people's life and production there. Based on the observational records from the Dasha River, the authors analyze the character of the variation in flow and sediment in different flood and dry seasons from 1970 to 2000. The result shows that human activities had significantly reduced the sediment discharge and sediment module, and increased the runoff in low-water seasons since the 1980s. The average contribution rate ofhnman activities to decreasing sediment was 65.67%, and at the same period the contribution rate of runoff and rainfall was about 34.33%. Therefore, it is necessary to take the biological and engineering measures to solve the problem of soil and water loss in the Dasha River watershed. 展开更多
关键词 river flow sediment discharge human activities effect Dasha River southwest of anhui province
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A Study of Chondrules in the Boxian Meteorite from Anhui Province, China
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作者 王奎仁 《Chinese Journal Of Geochemistry》 EI CAS 1988年第2期148-154,190-191,共9页
The types of chondrules in the Boxian meteorite have been determined Electron microprobe nalvsis ofvarious textural types of chondrules in the meteorite has revealed the composition ofglassy chondrules and oftheir gla... The types of chondrules in the Boxian meteorite have been determined Electron microprobe nalvsis ofvarious textural types of chondrules in the meteorite has revealed the composition ofglassy chondrules and oftheir glassy matrix,Also presented in this paper are the related explanations.In addition.the genesis,texturaldiversity and evolution of the chondrules as well as the olivine girdles observed in the chondrules arediscussed. 展开更多
关键词 A Study of Chondrules in the Boxian Meteorite from anhui province China
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STUDY OF MINERALIZATION OF HOUQIU METAMORPHOSE SEDIMENTARY IRON DEPOSIT, WEST ANHUI PROVINCE,EAST CHINA
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《Geotectonica et Metallogenia》 1994年第Z2期43-45,共3页
关键词 EAST Ni STUDY OF MINERALIZATION OF HOUQIU METAMORPHOSE SEDIMENTARY IRON DEPOSIT WEST anhui province EAST CHINA
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TECTONOMAGMATIC ACTIVATION AND THE PREDICTION OF SAXI-CHANG PUSHANG PORPHYRE COPPER DEPOSIT, CENTRAL ANHUI PROVINCE,EAST CHINA
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《Geotectonica et Metallogenia》 1994年第Z2期83-84,共2页
关键词 EAST CENTRAL anhui province EAST CHINA TECTONOMAGMATIC ACTIVATION AND THE PREDICTION OF SAXI-CHANG PUSHANG PORPHYRE COPPER DEPOSIT
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Lower Triassic Inorganic Carbon Isotope Excursion in Chaohu, Anhui Province, China 被引量:26
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作者 Tong Jinnan Qiu Haiou Zhao Laishi Zuo Jingxun China University of Geosciences, Wuhan 430074 《Journal of China University of Geosciences》 SCIE CSCD 2002年第2期98-106,共9页
This paper reports a Lower Triassic inorganic carbon isotope profile from the North Pingdingshan Section in Chaohu, Anhui Province, China, which was situated in a deep part of the Lower Yangtze carbonate ramp. The ... This paper reports a Lower Triassic inorganic carbon isotope profile from the North Pingdingshan Section in Chaohu, Anhui Province, China, which was situated in a deep part of the Lower Yangtze carbonate ramp. The δ ( 13 C) excursion shows two periods from the Permian Triassic boundary to the lower Spathian substage, corresponding to the ecosystem undergoing evolution and recovery after the end Permian mass extinction and related events. The first period starts at the δ ( 13 C) depletion caused by the mass extinction and evolves with a gradual δ ( 13 C) increase resulting from the development of some disaster taxa during the Induan. The strong Smithian δ ( 13 C) depletion in the second period might be formed by the collapse of the disaster ecosystem and the biotic recovery occurred with the explosive increase of bioproductivity in the Spathian. Thus the δ ( 13 C) excursion in the Lower Triassic expresses patterns of biotic evolution and recovery during the erratic ecosystem that followed the great end Permian mass extinction. 展开更多
关键词 Lower Triassic inorganic carbon isotope extinction and recovery CHAOHU anhui province.
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Genetic Types and Metallogenic Model for the Polymetallic Copper–Gold Deposits in the Tongling Ore District, Anhui Province, Eastern China 被引量:7
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作者 FU Zhongyang XU Xiaochun +4 位作者 HE Jun FAN Ziliang XIE Qiaoqin DU Jianguo CHEN Fang 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2019年第1期88-110,共23页
The Tongling ore district is one of the most economically important ore areas in the Middle–Lower Yangtze River Metallogenic Belt, eastern China. It contains hundreds of polymetallic copper–gold deposits and occurre... The Tongling ore district is one of the most economically important ore areas in the Middle–Lower Yangtze River Metallogenic Belt, eastern China. It contains hundreds of polymetallic copper–gold deposits and occurrences. Those deposits are mainly clustered(from west to east) within the Tongguanshan, Shizishan, Xinqiao, Fenghuangshan, and Shatanjiao orefields. Until recently, the majority of these deposits were thought to be skarn-or porphyry–skarn-type deposits; however there have been recent discoveries of numerous vein-type Au, Ag, and Pb-Zn deposits that do not fall into either of these categories. This indicates that there is some uncertainty over this classification. Here, we present the results of several systematic geological studies of representative deposits in the Tongling ore district. From investigation of the ore-controlling structures, lithology of the host rock, mineral assemblages, and the characteristics of the mineralization and alteration within these deposits, three genetic types of deposits(skarn-, porphyry-, and vein-type deposits) have been identified. The spatial and temporal relationships between the orebodies and Yanshanian intrusions combined with the sources of the ore-forming fluids and metals, as well as the geodynamic setting of this ore district, indicate that all three deposit types are genetically related each other and constitute a magmatic–hydrothermal system. This study outlines a model that relates the polymetallic copper–gold porphyry-, skarn-, and vein-type deposits within the Tongling ore district. This model provides a theoretical basis to guide exploration for deep-seated and concealed porphyry-type Cu(–Mo, –Au) deposits as well as shallow vein-type Au, Ag, and Pb–Zn deposits in this area and elsewhere. 展开更多
关键词 POLYMETALLIC copper–gold deposits genetic types METALLOGENIC model magmatic–hydrothermal system TONGLING ore district anhui province
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Commelina communis L.: Copper Hyperaccumulator Found in Anhui Province of China 被引量:18
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作者 TANG SHIRONG HUANG CHANGYONG and ZHU ZUXIANG (Department of Soil Science, College of Environmental Sciences and Natural Resources, Zhejiang Agricultural University, Hangzhou 310029 China) 《Pedosphere》 SCIE CAS CSCD 1997年第3期207-210,共4页
Commelina communis L. growing over some new copper mining wastelands at Bijiashan, Tongling City of Anhui Province, China, was found to be a copper hyperaccumulator. Its copper concentrations were 2707-6159 (4439±... Commelina communis L. growing over some new copper mining wastelands at Bijiashan, Tongling City of Anhui Province, China, was found to be a copper hyperaccumulator. Its copper concentrations were 2707-6159 (4439±2434) mg kg-1, 369-831 (731±142) mg kg-1, and 429-587 (547±57) mg kg-1, respectively, in the roots, stems, and leaves. The soils supporting the growth of the species had a copper concentration ranging from 4620 to 5020 mg kg-1 and averaging 4835±262 mg kg-1, suggesting that the species could not only grow on heavily copper-contaminated soils but also accumulate extraordinarily high concentration of copper. Thus, it shows great potential in the phytoremediation of copper-contaminated soils,the restoration of mined land, geochemical prospecting, and the study of environmental pollution changes. 展开更多
关键词 anhui province Commelina communis L. copper hyperaccumulator
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Discussion on Induan-Olenekian Boundary in Chaohu, Anhui Province, China 被引量:7
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作者 Zhao Laishi Tong Jinnan Zuo Jingxun Ming Houli China University of Geosciences, Wuhan 430074 《Journal of China University of Geosciences》 SCIE CSCD 2002年第2期141-150,共10页
This paper proposes a scheme for the definition of the Lower Triassic Induan Olenekian boundary (IOB) based on investigation of sections in Chaohu, Anhui Province, China as well as data accumulated from other studies... This paper proposes a scheme for the definition of the Lower Triassic Induan Olenekian boundary (IOB) based on investigation of sections in Chaohu, Anhui Province, China as well as data accumulated from other studies elsewhere. The conodont Neospathodus waageni is suggested as the index fossil of the boundary. According to the FAD of N. waageni , the IOB is at the base of bed 25 2 of the West Pingdingshan Section in Chaohu, 42.19 m above the Permian Triassic boundary, and it is slightly higher than the base of the Flemingites Euflemingites Ammonoid Zone at the section. 展开更多
关键词 Lower Triassic Induan Olenekian boundary conodont biostratigraphy CHAOHU anhui province.
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Geochemical Characteristics of Sedimentary Manganese Deposit of Guichi, Anhui Province, China 被引量:5
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作者 谢建成 杨晓勇 +1 位作者 杜建国 许卫 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第3期374-380,共7页
The sedimentary manganese deposits occurring in Gufeng formation of the Permian in Guichi area, south Anhui Province, include manganese carbonate deposit formed by sedimentation, and manganese oxide deposit made by la... The sedimentary manganese deposits occurring in Gufeng formation of the Permian in Guichi area, south Anhui Province, include manganese carbonate deposit formed by sedimentation, and manganese oxide deposit made by later oxidation. The total REE contents of these samples are relatively low ( 〈 250 × 10^- 6), belonging to LREE-enriched type, showing LREE enrichment during the process of formation of Mn deposit, especially during Mn-oxidizing process. Three normalized REE patterns and SCNA-normalized trace elements spider diagrams of the Mn-bearing sequence rocks and ores in this area reflect their same origin of ore sources, which is similar to rock-forming and ore-forming conditions. The Mnforming materials primarily came from the continent with higher mature degree and single material source. The δEu and δCe negative anomaly and Ce anomaly ( 〈 - 0.1) manifest that Mn-bearing sequence of the Permian was mostly formed in marine basin and oxidative environment. The Sr and Ba anomaly, Sr/Ba and Co/Ni values reflect the Mn deposit environment was of deep water and high-salinity of marine facies. Although the Ce/La (mean 1.05), Y/Ho (25 - 41.5) and trace metals show a variety of correlations with Mn in the ten rock samples, which show multiple sources for the manganese, the analysis of geochemical characteristics indicate that the material sources of Mn deposit have been primarily terrestriallyderived. Another source of the manganese probably comes from the seafloor volcanism in this area. Analysis of sedimentary features and geohistoric evolvement reveals that the maximum transgression of the Qixia Period, ore district is then in deep shelf-basin sedimentary setting and the Mn-bearing sequence is deposited. 展开更多
关键词 manganese ore trace elements GEOCHEMISTRY Guichi area anhui province rare earths
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An investigation of weed seed banks reveals similar potential weed community diversity among three different farmland types in Anhui Province, China 被引量:4
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作者 HE Yun-he GAO Ping-lei QIANG Sheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第4期927-937,共11页
Crop type is one of main factors influencing weed community structure. However, the identity of weed communities associated with the cultivation of different crops in farmlands remains largely unclear. A field survey ... Crop type is one of main factors influencing weed community structure. However, the identity of weed communities associated with the cultivation of different crops in farmlands remains largely unclear. A field survey of weed seed banks was conducted in 2 280 fields at 228 sites of 62 locations representing three different types of farmland(95 paddy, 73 summer-ripe, and 60 autumn-ripe farmlands) along the bank of the Yangtze River in Anhui Province, China. A total of 43 families and 174 species of weeds were found in these weed seed banks. A comparison of the composition of weed groups in the seed banks showed that the species number and density percentage of grass, sedge and broadleaf weed groups were similar among the different types of farmland. The seed banks of all three farmland types shared 71 common weed species, accounting for 40.80% of the total number of species. These common weeds, which were both associated and not associated with crops, accounted for 91.71% of the total dominance degree among all farmland types. The crop-associated weed species were distributed in all soil layers of each farmland type. The Shannon-Wiener index H′(description of species diversity which is more sensitive to dense species) and Pielou's evenness index J(description of species evenness) in summer-ripe farmland were similar to those in autumn-ripe farmland but differed from those in paddy farmland. However, the Simpson's index D(description of species diversity which is more sensitive to sparse species) was similar among all three farmland types. The results of similarity comparison indicated that although the aboveground weed community differed among the different cropping patterns, the weed species composition in the soil seed bank was still similar. Consequently, our results demonstrate that after the implementation of long-term monoculture patterns, weed species compositions in the soil seed bank in different farmlands become homogenized regardless of the crop type. 展开更多
关键词 species compositi on domi nance degree COMM UNITY similarity COMM UNITY variati on anhui province
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Granulite-facies Middle-Lower Crustal Xenoliths from Nushan Alkali Basalt in Northeastern Anhui Province,China 被引量:5
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作者 于津海 周新民 《Chinese Journal Of Geochemistry》 EI CAS 1993年第4期339-352,共14页
Metamorphic xenoliths within the Nushan alkali basalt of northeastern Anhui (NEA),China ,are from the middle-lower crust.They could be divided into two end-members:basic and acid.Interme-diate xenoliths are scarcely f... Metamorphic xenoliths within the Nushan alkali basalt of northeastern Anhui (NEA),China ,are from the middle-lower crust.They could be divided into two end-members:basic and acid.Interme-diate xenoliths are scarcely found.Basic two-pyroxene granulites(pyriclasites) were formed at 720-810℃ and 7-8kb.Petrological and geochemical studies indicate that the primary magma of the protoliths of basic granulites was derived from the metasomatized upper mantle, while the pa-rental magma of the acid end-member was probably produced by partial melting of the basic rocks. The protoliths of charnockites and grey gneisses represent respectively the early and late crystallization products of the granitic magma.The Nushan granulites are much different in many aspects from the granulites exposed in the northern part of North China ,which implies the inhomogeneity regarding to the early evolution of the North China terranc. 展开更多
关键词 XENOLITH alkali basait granulite facies Nushan anhui province
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Geology, Geochemistry, and Geochronology of the Fenghuangshan Skarn-type Copper Deposit in the Tongling Ore Cluster, Anhui Province, East China 被引量:3
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作者 QU Hongying PEI Rongfu +4 位作者 FEI Hongcai LI Jinwen WANG Yonglei WANG Haolin YAO Lei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第3期700-718,共19页
The Fenghuangshan skarn-type Cu deposit, Tongling Ore Cluster, Anhui Province, is an important component in the Middle-Lower Yangtze River ore-forming belt. To better understand magmatism and its relationship to miner... The Fenghuangshan skarn-type Cu deposit, Tongling Ore Cluster, Anhui Province, is an important component in the Middle-Lower Yangtze River ore-forming belt. To better understand magmatism and its relationship to mineralization, we investigated geochemical features, ore-forming fluids, and geochronology of the Xinwuli intrusion and the related Fenghuangshan Cu deposit. Lithogeochemical characteristics show that the Xinwuli quartz monzodiorite is formed by mixing magma derived from upper mantle alkaline basalt that has been contaminated by crust materials. C, H and O isotopes indicate that ore-forming fluids mainly come from the magma, with minor amounts of meteoric fluids involved at the late stage. S and Pb isotopic components indicate that ore-forming materials are derived from the mantle. Molybdenite Re-Os isotopic dating yields Re-Os model ages ranging from 139.1±2.4 Ma to 142.0±2.2 Ma, with an isochronal age of 141.1±1.4 Ma, which is consistent with sensitive, high-resolution ion microprobe (SHRIMP) zircon U-Pb ages of quartz monzodiorite and granodiorite in the mining area. Dating analysis yields ages from 136.0±2.0 Ma to 143.0±2.4 Ma for the quartz monzodiorite (a weighted average of 139.4±1.2 Ma) and ages from 136.7±2.0 Ma to 145.3±2.4 Ma for granodiorite (a weighted average of 141.0±1.1 Ma). 展开更多
关键词 Ore-forming fluids isotopes molybdenite Re–Os ages SHRIMP zircon U–Pb ages Fenghuangshan Cu deposit anhui province
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