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Influence of the environmental behavior and ecological effect of cropland heavy metal contaminants by CO_2 enrichment in atmosphere 被引量:4
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作者 Hongyan GUO Haixia JIA +1 位作者 Jianguo ZHU Xiaorong WANG 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期212-212,共1页
关键词 环境行为 生态效应 重金属 环境污染 大气污染 二氧化碳 FACE
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Changes in manganese and lead in the environment and young children associated with the introduction of MMT in gasoline 被引量:2
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作者 Brian Gulson Karen Mizon +5 位作者 Michael Korsch Honway Louie Michael Wu Jenny Stauber J. Michael Davis Alan Taylor 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期62-62,共1页
关键词 血液 导联 环境危害 青少年 汽油 环境医学 环境卫生
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Evaluation of the Contribution of Aerosols in the Contamination of the Environment in the Greater Casablanca
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作者 HADER Khadija Lahcen BAHI 《Journal of Earth Science and Engineering》 2016年第2期110-113,共4页
关键词 环境污染 气溶胶 评价 空气质量 污染损害 工业发展 就业机会 大城市
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Towards an integrative approach to evaluate the environmental ecosystem services provided by urban forest
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作者 Samson Roeland Marco Moretti +11 位作者 Jorge Humberto Amorim Cristina Branquinho Silvano Fares Federico Morelli Ulo Niinemets Elena Paoletti Pedro Pinho Gregorio Sgrigna Vladimir Stojanovski Abhishek Tiwary Pierre Sicard Carlo Calfapietra 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第6期1981-1996,共16页
As a Nature-Based Solution,urban forests deliver a number of environmental ecosystem services(EESs).To quantify these EESs,well-defined,reliable,quantifiable and stable indicators are needed.With literature analysis a... As a Nature-Based Solution,urban forests deliver a number of environmental ecosystem services(EESs).To quantify these EESs,well-defined,reliable,quantifiable and stable indicators are needed.With literature analysis and expert knowledge gathered within COST Action FP1204 GreenInUrbs,we proposed a classification of urban forest EESs into three categories:(A)regulation of air,water,soil and climate;(B)provisioning of habitat quality;and(C)provisioning of other goods and services.Each category is divided into EES types:(a)amelioration of air quality;restoration of soil and water;amelioration of the microclimate;removal of CO2 from the air;(b)provision of habitat for biodiversity;support for resilient urban ecosystems;provision of genetic diversity;and(c)provision of energy and nutrients;provision of grey infrastructure resilience.Each EES type provides one or more benefits.For each of these 12 benefits,we propose a set of indicators to be used when analyzing the impacts on the identified EESs.Around half of the 36 indicators are relevant to more than one single benefit,which highlights complex interrelationships.The indicators of wider applicability are tree and stand characteristics,followed by leaf physical traits and tree species composition.This knowledge is needed for the optimization of the EESs delivered by urban forests,now and in the future. 展开更多
关键词 URBAN FORESTS Environmental ECOSYSTEM services INDICATORS
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Sedimentary Environment and Mineralization of the Black Shale Polymetallic Layer in the Early Cambrian,SW China:Constraints from in situ LA-ICP-MS Analysis of Pyrite
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作者 YANG Zhen FU Yong +2 位作者 LI Chao CAI Xi GUO Chuan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期416-429,共14页
A polymetallic layer is usually developed at the bottom of the early Cambrian black shale in Guizhou Province.The mineral that makes up the polymetallic layer is related to the sedimentary facies.To analyze the differ... A polymetallic layer is usually developed at the bottom of the early Cambrian black shale in Guizhou Province.The mineral that makes up the polymetallic layer is related to the sedimentary facies.To analyze the differentiation mechanism between polymetallic deposits(Ni-Mo and V),the Zhijin Gezhongwu profile located in the outer shelf and the Sansui Haishan V deposit located in the lower slope are selected to study the in situ sulfur isotopes and trace elements of pyrite.The results show that δ^(34)S values of pyrite vary widely from−7.8‰to 28‰in the Gezhongwu profile,while the δ^(34)S values are relatively uniform(from 27.8‰to 38.4‰)in the Haishan profile.The isotopic S composition is consistent with the transition that occurs in the sedimentary phase from the shelf to the deep sea on the transgressive Yangtze platform;this indicates that the δ^(34)SO_(4)^(2−)values in seawater must be differently distributed in depositional environments.The sulfur in the Ni-Mo layer is produced after the mixing of seawater and hydrothermal fluid,while the V layer mainly originates from seawater.Overall,the Ni-Mo and V deposits have been differentiated primarily on the basis of the combined effect of continental weathering and hydrothermal fluid. 展开更多
关键词 sedimentary environment black shale polymetallic layer PYRITE early Cambrian
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Flora, Structure and Carbon Sequestration of Vegetation in the Southeast of the Mono Biosphere Reserve in Togo Amidst Environmental Challenges
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作者 Gbétey Kokouvi Akpamou Kossi Adjossou +3 位作者 Hodabalo Egbelou Komlanvi Katche Akoete Kossi Hounkpati Kouami Kokou 《Open Journal of Forestry》 2024年第2期155-181,共27页
In most Sub-Saharan African countries such as Togo, people’s heavy dependence on ecosystem services is a major factor in accelerating the degradation of natural resources, which are already suffering as a result of c... In most Sub-Saharan African countries such as Togo, people’s heavy dependence on ecosystem services is a major factor in accelerating the degradation of natural resources, which are already suffering as a result of climatic factors. This study was initiated to contribute to the sustainable and rational management of forest resources in the south-east of the Mono Biosphere Reserve in Togo. It specifically aims to identify and characterize the flora of the residual forest ecosystems within the reserve through their specific diversity, demographic structure, and carbon sequestration potential. The study was carried out in the forest ecosystems of Avévé. The methodology used was based on the analysis of phytosociological, forestry, ecological, and regeneration inventory data. Overall, the study revealed that the RBMT still has floristically viable habitats, despite the anthropogenic pressures it is subject to revealed a floristic diversity of 160 plant species divided into 52 families and 135 genera. The most represented families are Rubiaceae (29.09%), followed by Fabaceae (27.94%). The most represented species are Mitragyna inermis (Willd.) Kuntze (24.38%), Lecaniodiscus cupanioides Planch. Ex Benth (X) and Lonchocarpus sericeus (Poir.) Kunth (10.93%). The high presence of Mitragyna inermis observed in all the ecological groups identified makes it the characteristic species of the flooded marshy areas of southeast Togo and contributes to the resilience of the ecosystems and populations in the study area. The Shannon index for the formation groups varies between (3.03 and 5.16) bits. Pielou’s equitability varies between (0.43 and 0.63) bits. The overall average density is estimated at 210 stems/ha, with an average diameter of 25.57 ± 21.77 m and an average height of 7.93 ± 3.83 m. The adjustment of the diameter classes of the plant groups to the Weibull distribution gave an “inverted J” shape with coefficient values of less than 1 overall, reflecting the existence of multispecific or uneven-aged stands. Assessment of the horizontal and vertical structure shows a predominance of the shrub layer in all the groups identified. The carbon sequestration potential is 41.89 T/Ha. Despite ongoing anthropogenic pressures, the Mono Biosphere Reserve abounds in a relatively rich diversity of flora, the preservation of which is essential for the survival of biodiversity and even for the riparian population. The data provided by this study would form the basis for sustainable management planning of the forest islands in the biosphere reserve. 展开更多
关键词 BIODIVERSITY Demographic Structure Carbon Biosphere Reserve Forest Patches TOGO
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Responses of breeding waterbird communities to environmental changes in subsidence wetlands in the North China Plain 被引量:1
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作者 Guangyao Wang Jinming Zhao +4 位作者 Weiqiang Li Xiangrong Song Yong Zhang Chunlin Li Willem F.de Boer 《Avian Research》 SCIE CSCD 2023年第3期336-344,共9页
In the context of global degradation and loss of natural wetlands,waterbirds have been increasingly using artificial wetlands as alternative habitats.However,waterbirds are facing various threats in these artificial w... In the context of global degradation and loss of natural wetlands,waterbirds have been increasingly using artificial wetlands as alternative habitats.However,waterbirds are facing various threats in these artificial wetlands,due to dramatic environmental changes induced by anthropogenic activities.Exploring the effects of these changes on the temporal dynamics of the waterbird communities can help understand how waterbirds adapt to environmental changes and thus formulate effective management and conservation plans.In this study,we carried out field surveys on waterbirds and environmental factors across 20 subsidence wetlands created by underground coal mining in the Huainan coal mining area in the breeding seasons of 2016 and 2021.We predicted that the waterbird assemblages(i.e.,number of individuals,species richness,Shannon-Wiener diversity,Pielou evenness and species composition) differed between the two years,and that these differences were correlated with the temporal changes in environmental factors.Across the surveyed wetlands,we recorded 26 waterbird species in 2016 and 23 in 2021.For individual wetlands,the number of waterbird individuals and species richness increased by 71.6% and 20.1%,respectively,over the five years,with no changes in Shannon-Wiener diversity and Pielou evenness.The overall increase in the number of bird individuals was mainly caused by an increase in vegetation gleaners and gulls that adapt well to anthropogenic activities.The species composition was significantly different between the two years,which was mainly caused by changes in the number of individuals of dominant species under influence of changes in human activities.For most wetlands,the temporal pairwiseβ-diversities could be explained by species turnover rather than nestedness,probably due to high mobility of waterbird species and dramatic changes in local environments.Our study suggests that waterbird communities could respond to environmental changes in subsidence wetlands,providing important implications for waterbird conservation in human-dominated artificial wetlands. 展开更多
关键词 Artificial wetlands Environmental changes Subsidence wetlands Waterbird community
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Experimental and Numerical Evaluation of the Cavitation Performances of Self-Excited Oscillating Jets
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作者 Yuanyuan Zhao Fujian Zhao +2 位作者 Guohui Li Wei Xu Xiuli Wang 《Fluid Dynamics & Materials Processing》 EI 2024年第8期1883-1901,共19页
Self-excited oscillating jets(SOJ)are used in several practical applications.Their performances are significantly affected by structural parameters and the target distance.In this study,a geometric model of the SOJ no... Self-excited oscillating jets(SOJ)are used in several practical applications.Their performances are significantly affected by structural parameters and the target distance.In this study,a geometric model of the SOJ nozzle accounting for multiple structural parameters is introduced,then the related cavitation performances and the optimal target distance are investigated using a Large-Eddy Simulation(LES)approach.Results are also provided about an experiment,which was conducted to validate the simulation results.By analyzing the evolution of the vapor volume fraction at the nozzle outlet,a discussion is presented about the effect of the aforementioned structural parameters on the cavitation performances and the target distance.It is shown that the distribution of cavitation clouds at the outlet of the SOJ nozzle displays a non-monotonic trend(first increasing,then decreasing).Under working conditions with an inlet pressure of 4 MPa,a SOJ nozzle outlet/inlet diameter ratio(D_(1)/D_(2))of 1.2,and a chamber diameter ratio(D/L)close to 1.8,the nozzle outlet cavitation performance attains a maximum.The optimal structural parameters correspond to the optimal target distance,which is near 50 mm.The experiments have revealed that the SOJ nozzle with the above parameters displays a good cavitation erosion effect at the target distance of 50 mm,in satisfactory agreement with the numerical simulation results. 展开更多
关键词 Self-excited oscillating nozzle cavitating jet target distant LES CAVITATION
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Numerical study on gas production via a horizontal well from hydrate reservoirs with different slope angles in the South China Sea
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作者 Tingting Luo Jianlin Song +5 位作者 Xiang Sun Fanbao Cheng Madhusudhan Bangalore Narasimha Murthy Yulu Chen Yi Zhao Yongchen Song 《Deep Underground Science and Engineering》 2024年第2期171-181,共11页
It is important to study the effect of hydrate production on the physical and mechanical properties of low-permeability clayey–silty reservoirs for the largescale exploitation of hydrate reservoirs in the South China... It is important to study the effect of hydrate production on the physical and mechanical properties of low-permeability clayey–silty reservoirs for the largescale exploitation of hydrate reservoirs in the South China Sea.In this study,a multiphysical-field coupling model,combined with actual exploration drilling data and the mechanical experimental data of hydrate cores in the laboratory,was established to investigate the physical and mechanical properties of low-permeability reservoirs with different slope angles during 5-year hydrate production by the depressurization method via a horizontal well.The result shows that the permeability of reservoirs severely affects gas production rate,and the maximum gas production amount of a 20-m-long horizontal well can reach186.8 m3/day during the 5-year hydrate production.Reservoirs with smaller slope angles show higher gas production rates.The depressurization propagation and hydrate dissociation mainly develop along the direction parallel to the slope.Besides,the mean effective stress of reservoirs is concentrated in the near-wellbore area with the on-going hydrate production,and gradually decreases with the increase of the slope angle.Different from the effective stress distribution law,the total reservoir settlement amount first decreases and then increases with the increase of the slope angle.The maximum settlement of reservoirs with a 0°slope angle is up to 3.4 m,and the displacement in the near-wellbore area is as high as2.2 m after 5 years of hydrate production.It is concluded that the pore pressure drop region of low-permeability reservoirs in the South China Sea is limited,and various slope angles further lead to differences in effective stress and strain of reservoirs during hydrate production,resulting in severe uneven settlement of reservoirs. 展开更多
关键词 effective stress low‐permeability reservoirs natural gas hydrate production numerical simulation SETTLEMENT slope angle the South China
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A Comprehensive Analysis of the Thermo-Chemical Properties of Sudanese Biomass for Sustainable Applications
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作者 Wadah Mohammed Zeinab Osman +1 位作者 Salah Elarabi Bertrand Charrier 《Journal of Renewable Materials》 EI CAS 2024年第4期721-736,共16页
The chemical composition and thermal properties of natural fibers are the most critical variables that determine the overall properties of the fibers and influence their processing and use in different sustainable app... The chemical composition and thermal properties of natural fibers are the most critical variables that determine the overall properties of the fibers and influence their processing and use in different sustainable applications,such as their conversion into bioenergy and biocomposites.Their thermal and mechanical properties can be estimated by evaluating the content of cellulose,lignin,and other extractives in the fibers.In this research work,the chemical composition and thermal properties of three fibers,namely bagasse,kenaf bast fibers,and cotton stalks,were evaluated to assess their potential utilization in producing biocomposites and bioenergy materials.The chemical composition analysis followed the Technical Association of the Pulp and Paper Industry Standards(TAPPI)methods.The total phenol content was quantified using the Folin-Ciocalteu method,while Fourier Transform Infrared Spectroscopy(FTIR)was employed to assess the light absorption by the bonds.To evaluate thermal stability and higher heating values,Thermogravimetric Analysis(TGA),Differential Scanning Calorimetry(DSC),and bomb calorimetry were performed.The chemical analysis revealed that bagasse contained 50.6%cellulose and 21.6%lignin,kenaf bast fibers had 58.5%cellulose and 10%lignin,and cotton stalks exhibited 40.3%cellulose and 21.3%lignin.The FTIR curves demonstrated a notable similarity among the fibers.The TGA analysis showed degradation temperatures of 321°C for bagasse,354°C for kenaf bast fibers,and 289°C for cotton stalks.The DSC analysis revealed glass transition temperatures of 81°C for bagasse,66.3°C for cotton stalks,and 64.5°C for kenaf bast fibers.The higher heating values were measured as 17.3,16.6 and 17.1 MJ/kg for bagasse,kenaf bast fibers,and cotton stalks,respectively.The three fibers have a high potential for biocomposites and bioenergy material manufacturing. 展开更多
关键词 BAGASSE kenaf bast fibers cotton stalks TGA DSC FTIR
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Structural Elucidation of the Polymeric Condensed Tannins of Acacia nilotica Subspecies by ^(13)C NMR, MALDI-TOF and TMA as Sources of Bioadhesives
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作者 Zeinab Osman Antonio Pizzi Bertrand Charrier 《Journal of Renewable Materials》 EI CAS 2024年第7期1291-1310,共20页
Tannin was extracted from different subspecies of Acacia nilotica,Acacia nilotica nilotica(Ann),Acacia nilotica tomentosa(Ant)and Acacia nilotica adansonii(Ana).The aim was to elucidate their structure and evaluate th... Tannin was extracted from different subspecies of Acacia nilotica,Acacia nilotica nilotica(Ann),Acacia nilotica tomentosa(Ant)and Acacia nilotica adansonii(Ana).The aim was to elucidate their structure and evaluate their reactivity as bioadhesives in the wood industry.The extracts were prepared by hot water extraction(90°C tem-perature).Their gel time with paraformaldehyde was used atfirst to compare their reactivity.The tannin contents and the percentage of total polyphenolic materials in different solutions of the extracts spray dried powder were determined by the hide powder method.Concentrated solutions(47%)were tested by both MALDI ToF,13CNMR.The thermomechanical analysis(TMA)was performed to evaluate their modulus of elasticity(MOE)at different pHs.The gel times of all the three tannin extracts showed that their reactivity and it was com-parable to other known procyanidin/prodelphinidin tannin extract types.Ana,Ann and Ant showed highest per-cent of total polyphenolic materials at 70%,64%,and 57%,respectively.The 13CNMR spectra showed that the three subspecies of condensed tannins were mainly constituted of procyanidins(PC)and prodelphinidins(PD)in slightly different ratios.Ann(56.5%PC and 43.4%PD),Ant(57%PC and 43%PD)and Ana(58%PC and 42%PD).MALDI–TOF spectra showed the presence offlavonoid monomers,and oligomers some of which linked to short carbohydrates monomers or dimers.TMA revealed that the three types of tannins had high MOE at their initial pH(5). 展开更多
关键词 Acacia nilotica condensed tannins PROCYANIDINS prodelphinidins 13C NMR MALDI-TOF
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Detour for the inexperienced? Migration count data suggest mostly juvenile Greater Spotted Eagles appear in coastal peninsulas in China
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作者 Xu Shi Xiaoping Wang +2 位作者 Qian Wei Qiwei Lin Lei Zhu 《Avian Research》 SCIE CSCD 2024年第2期249-254,共6页
Soaring bird migration often relies on suitable terrain and airflow;therefore,route selection is vital for successful migration.While age and experience have been identified as key factor influencing migration route s... Soaring bird migration often relies on suitable terrain and airflow;therefore,route selection is vital for successful migration.While age and experience have been identified as key factor influencing migration route selection among soaring raptors in the African-Eurasian Flyway,how they shape the migration route of soaring raptors in East Asia is still largely unknown.In this study,we investigated potential variations in the routes and timing in autumn migration of juvenile and older soaring birds,using count data of Greater Spotted Eagles(Clanga clanga)from two coastal sites and two inland sites in China.From 2020 to 2023,we recorded a total of 340 individuals,with the highest site averaging over 90 individuals per autumn,making it one of the world’s top single-season counts and thus a globally important site for this species.We found that 82% and 61% records from coastal sites were juveniles,significantly higher than inland sites(15% and 24%).Juveniles at all four sites exhibited markedly earlier median passage time than non-juveniles,with brief overlapping in their main migration periods.Both coastal sites are located on the tip of peninsulas stretching southwest,requiring long overwater flights if crossing the Bohai Bay or Beibu Gulf,which would be energetically demanding and increase mortality risk.Experienced individuals may have learned to avoid such terrain and subsequent detour,while juveniles are more prone to enter these peninsulas due to lack of experience and opportunities for social learning,or following other raptor species that are more capable of powered flight.Our findings highlight the importance of age and experience in migration route selection of large soaring birds. 展开更多
关键词 Clanga clanga East Asia Greater Spotted Eagle JUVENILE Migration route Social learning
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Participatory Technique Supporting Environmental Management: A Systematic and Bibliometric Review
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作者 Barbara Rentes Barbosa Fabiana Da Silva Soares +2 位作者 Luiz Carlos De Faria Kaline De Mello Roberta Averna Valente 《Journal of Environmental Protection》 2024年第7期781-795,共15页
The increasing need to manage natural resources sustainably, driven by population growth, requires the simultaneous use of Participatory Techniques (PT) and landscape planning for structured decision-making. We conduc... The increasing need to manage natural resources sustainably, driven by population growth, requires the simultaneous use of Participatory Techniques (PT) and landscape planning for structured decision-making. We conducted a bibliometric and systematic review to provide an overview of PT usage, identifying evolution in scientific production. We considered the number of publications and citations, prominent journals, and highly cited articles on scientific papers published in the Web of Science database between 1993 and 2023. A total of 415 articles related to PT were identified. After content evaluation, 19 critical articles were selected that underpin the growing combined use of models and indices with PT, enhancing the robustness and credibility of decision-making processes. 展开更多
关键词 PARTICIPATION Landscape Planning Decision-Making Process STAKEHOLDERS Sustainable Management
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Growth, Population Parameters and Stock Status of Sarotherodon galilaeus in Samandeni Reservoir, Burkina Faso
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作者 Nomwine Da Raymond Ouedraogo +1 位作者 Mahamoudou Minoungou Adama Oueda 《Open Journal of Ecology》 2024年第4期257-273,共17页
Mango tilapia, Sarotherodon galilaeus is one of the most caught fish species in the Samandeni multi-species fishing sites of which, few data on its biology and exploitation are available. The study aimed to Assess the... Mango tilapia, Sarotherodon galilaeus is one of the most caught fish species in the Samandeni multi-species fishing sites of which, few data on its biology and exploitation are available. The study aimed to Assess the stock status of S. galilaeus. Sampling was conducted from March, 2021 to February 2022 based on commercial fish catches to analyze growth parameters, first sexual maturity size and harvest status of the stock. A total of 572 specimens including 297 females and 275 males were examined. The stock assessment was performed by using the Length based Bayesian method of Biomass (LBB) and that of growth by the ELEFAN method. The growth parameters showed a seasonality of growth and females appeared to grow faster than males. On the other hand, males had a greater asymptotic length than females. Results on the estimated length of fish at first maturity showed that females firstly reached the maturity compared to males. The relative biomass (B/B<sub>0</sub>) estimated for the stock was higher than the relative biomass that produces maximum sustainable yield (B<sub>MSY</sub>/B<sub>0</sub>) indicating healthy biomass. In addition, the length at first sexual maturity was less than the length at the first catch, indicating the absence of overfishing of growth. In addition, extending the study to the various stocks of the reservoir would be important for the sustainable management of the Samandeni high economic fishing area. 展开更多
关键词 GROWTH Stock Status Sarotherodon galilaeus Samandeni Reservoir MATURITY
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Carbon Footprint in Waste Sector of Hydropower Plant: A Case Study of Nam Theun 2 Hydropower Plant
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作者 Souttiphong Keovongsa Keophousone Phonhalath Sengthavy Phommixay 《American Journal of Climate Change》 2024年第2期209-229,共21页
While hydropower is generally considered a clean energy source, it is important to recognize that their waste can still contribute to greenhouse gas emissions (GHG). The purpose of this study is to assess the carbon f... While hydropower is generally considered a clean energy source, it is important to recognize that their waste can still contribute to greenhouse gas emissions (GHG). The purpose of this study is to assess the carbon footprint associated with the waste sector throughout the operational phase of the Nam Theun 2 hydropower plant in Laos. Understanding the environmental impact of the waste sector is crucial for ensuring the plant’s sustainability. This study utilizes the theoretical estimation method recommended in the 2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories, as well as the Requirements for Specification with guidance at the organization level for quantification and reporting of GHG emissions and removals. We emphasize the significance of implementing sustainable waste management practices to reduce GHG emissions and minimize the environmental impact of hydropower operations. By conducting a comprehensive analysis, this paper also provides insights into the environmental implications of waste management in hydropower plants and identifies strategies to mitigate the carbon footprint in the waste sector. The findings contribute to a better understanding of the environmental sustainability of hydropower plants and provide valuable guidance for policymakers, energy producers, and environmental practitioners involved in hydropower plant design and operation. 展开更多
关键词 Waste Sector Carbon Footprint Climate Change Hydropower Plant
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Arlenea delicata gen.et sp.nov.,a new ephedroid plant from the Early Cretaceous Crato Formation,Araripe Basin,Northeast Brazil
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作者 Alita Maria Neves Ribeiro Yong Yang +3 位作者 Antonio Alamo Feitosa Saraiva Renan Alfredo Machado Bantim Joao Tavares Calixto Junior Flaviana Jorge de Lima 《Plant Diversity》 SCIE CAS CSCD 2024年第3期362-371,共10页
Ephedroid macrofossils have been widely documented in Cretaceous deposits,including numerous from the Lower Cretaceous Yixian Formation of NE China.However,few ephedroid macrofossils have been reported from South Amer... Ephedroid macrofossils have been widely documented in Cretaceous deposits,including numerous from the Lower Cretaceous Yixian Formation of NE China.However,few ephedroid macrofossils have been reported from South America.Herein,we describe a new plant of the family Ephedraceae,Arlenea delicata gen.et sp.nov.,from the Lower Cretaceous Crato Formation of the Araripe Basin,Northeast Brazil,based on the vegetative and reproductive structures.It has the typical morphological characteristics of ephedroid plants,including fertile reproductive branches,opposite phyllotaxy,terminal female cones,a sympodial branching system,longitudinally striated internodes,and swollen nodes.Our new finding is unusual in having inner chlamydosperms subtended by two pairs of bracts,reproductive units connected to branches through swollen receptacles and a smooth seed surface.This new ephedroid taxon from the Crato Formation increases our understanding of plant diversity of this group during the Early Cretaceous.Furthermore,the general morphology(fleshy bracts and enlarged receptacles)of this new fossil discovery indicates that seeds of this plant may have been dispersed by animals such as pterosaurs(mainly the Tapejaridae)and birds(Enantiornithes and Ornituromorpha).If true,this would explain the cosmopolitan distribution of Ephedraceae in the Lower Cretaceous. 展开更多
关键词 Early Cretaceous Gnetophytes Arlenea delicata Ephedrales Crato Formation
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Fragipan Horizon Changes Using Annual Ryegrass and Other Admendments
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作者 Lloyd Murdock Anastasios Karathanasis +2 位作者 Dottie Call Dana L. Dinnes Amitava Chatterjee 《Open Journal of Soil Science》 2024年第6期388-397,共10页
A greenhouse experiment was conducted involving intact fragipan soil cores of 50 cm thickness after removing the topsoil horizons. The cores were maintained in moist condition throughout the experiment and received se... A greenhouse experiment was conducted involving intact fragipan soil cores of 50 cm thickness after removing the topsoil horizons. The cores were maintained in moist condition throughout the experiment and received several treatments with various amendments for different periods ranging from 9 to 17 months. The amendments included annual ryegrass or Festulolium residues, powder limestone and various humate compounds alone or in combination with the grass residues. The results suggested a significant effect of ryegrass and Festulolium in reducing penetration resistance into the top 10 cm of the fragipan within 9 - 17 months, particularly when used in combination with certain humate materials such as Leonardite. Apparently, this is the result of the release of certain soluble organic compounds from the plant residues or the humate amendments that increase the solubility of Si and Al associated with the fragipan brittleness, thus decreasing the density of the compacted fragipan material. 展开更多
关键词 Fragipan Fragipan Horizon Fragipan Soils Changing the Fragipan Annual Ryegrass Changes Fragipan Festulolium Changes Fragipan Amendments That Change the Fragipan
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Phytochemical Composition and Insecticidal Property of Native Plants against the Cowpea Weevil Callosobruchus maculatus Fab. (Coleoptera: Bruchidae) for Natural Preservation of Cowpea Seeds
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作者 Elias Mano Rabièta Simde +6 位作者 Koï Wenceslas Kam Nadjatou Ouédraogo Désiré Dramane Abdoul Khader Sanou Rasmané Abdou Ouédraogo Boubakar Ouattara Pierre Alexandre Eric Djifaby Sombié Souleymane Nacro 《Advances in Entomology》 2024年第1期56-66,共11页
About 80% of cowpea seeds are lost along with 30% of their weight after six months of unprotected storage due to attacks by Callosobruchus maculatus. This study aimed at evaluating the effect of applying bioinsecticid... About 80% of cowpea seeds are lost along with 30% of their weight after six months of unprotected storage due to attacks by Callosobruchus maculatus. This study aimed at evaluating the effect of applying bioinsecticides on the biological parameters of C. maculatus to reduce its damage to cowpea stocks. Four treatments including an untreated control and three doses of powdery extracts of C. nigricans, Z. zanthoxyloides and H. suaveolens, were compared in a Fischer block with four completely randomized repetitions. One hundred undamaged cowpea seeds were mixed with doses of each extract in Petri dishes and then fed as food substrates to ten pairs of C. maculatus for eight days. The extracts of H. suaveolens, C. nigricans and Z. zanthoxyloides all contain active ingredients including polyphenols, flavonoids, anthocyanins and alkaloids, etc. The extract of Z. zanthoxyloides was found to be more active on adults (100.00% mortality) followed by C. nigricans (98.75% mortality) and H. suaveolens (97.50% mortality) at 80 mg/g. Fecundity per female decreased significantly in the treated batches of 13.82 eggs for H. suaveolens at 10.12 eggs for C. nigricans at a dose of 80 mg/g. Germination rate of seeds was statistically raised to 100% at 60 and 80 mg/g by C. nigricans powder and lowered to 83.00% at 20 mg/g by Z. zanthoxyloides extracts. The application of Z. zanthoxyloides extract would be a less expensive alternative for the sustainable management of C. maculatus in cowpea stocks. 展开更多
关键词 Cassia nigricans Hyptis suaveolens Zanthoxylum zanthoxyloides Biological Activities Vigna unguiculata Pest Burkina Faso
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Calcium-Magnesium Ca/Mg Ratios and Their Agronomic Implications for the Optimization of Phosphate Fertilization in Rainfed Rice Farming on Acidic Ferralsol in the Forest Zone of Ivory Coast
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作者 Fernand G. Yao Brahima Kone +7 位作者 Franck M. L. Bahan Kouadio Amani Jean L. Essehi Mamadou B. Ouattara Konan E. B. Dibi Brou Kouame François Lompo Albert Yao-Kouame 《Open Journal of Soil Science》 2024年第1期81-96,共16页
This study is a contribution to improving rice productivity on acidic plateau soils of the tropical rainforest zone. It is based on taking into account the cationic balances of the soil in order to optimize the phosph... This study is a contribution to improving rice productivity on acidic plateau soils of the tropical rainforest zone. It is based on taking into account the cationic balances of the soil in order to optimize the phosphorus (P) nutrition of rice on these acidic soils, where this nutrient constitutes a limiting factor for agricultural production. Three (3) pot trials were conducted in Adiopodoumé in the forested south of Côte d’Ivoire. The interactive effects of calcium carbonate (0, 25, 50 and 75 kg Ca ha<sup>−1</sup>) and magnesium sulfate (0, 25, 50 and 75 kg Mg ha<sup>−1</sup>) were evaluated on the response of NERICA 5 rice at doses 0, 25, 50 and 75 kg P ha<sup>−1</sup> of natural phosphate from Togo, applied only once at the start of the experiment. Additional fertilizers of nitrogen (N) (100 kg N ha<sup>−1</sup>) and potassium (K) (50 kg KCl ha<sup>−1</sup>) were added to each of the tests in a split-plot device. The test results revealed a paddy production potential of approximately 3 to 5 t⋅ha<sup>−1</sup> for NERICA 5 on an acidic soil, under the effect of the interaction of P, Ca and Mg. The quadratic response of rice yield to the doses of these fertilizers would be more dependent on their balance, itself influenced by Ca nutrition. For the sustainability and maintenance of rice production in agro-ecology studied, it was recommended doses of 38 kg Ca ha<sup>−1</sup>, 34 kg Mg ha<sup>−1</sup> in a Ca/Mg ratio (1/1) with intakes of 41 kg P ha<sup>−1</sup>, overall in a ratio 1/1/1 (P/Ca/Mg) more favorable to the availability of free iron considered a guiding element of mineral nutrition. Thus, these promising results should be confirmed in a real environment for better management of the fertilization of rice cultivated on acidic plateau soils in Côte d’Ivoire. 展开更多
关键词 Soil Acidity Ca/Mg Ratios Phosphate Fertilization Rice Growing Ivory Coast
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Surface N balances and reactive N loss to the environment from global intensive agricultural production systems for the period 1970-2030 被引量:6
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作者 A.F.Bouwman G.Van Drecht K.W.van der Hoek 《Science China(Life Sciences)》 SCIE CAS 2005年第z2期767-779,共13页
关键词 surface N balances reactive N loss global intensive agricultural system.
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