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Seasonal Inhomogeneity of Soot Particles over the Central Indo-Gangetic Plains,India:Influence of Meteorology 被引量:3
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作者 SINGH B.P. TIWARI S. +8 位作者 HOPKE Philip K. SINGH R.S. BISHT D.S. SRIVASTAVA A.K. SINGH R.K. DUMKA U.C. SINGH A.K. RAI B.N. SRIVASTAVA Manoj K. 《Journal of Meteorological Research》 SCIE CSCD 2015年第6期935-949,共15页
Black carbon(BC) particles play a unique and important role in earth’s climate system.BC was measured(in-situ) in the central part of the Indo-Gangetic Plains(IGP) at Varanasi,which is a highly populated and po... Black carbon(BC) particles play a unique and important role in earth’s climate system.BC was measured(in-situ) in the central part of the Indo-Gangetic Plains(IGP) at Varanasi,which is a highly populated and polluted region due to its topography and extensive emission sources.The annual mean BC mass concentration was 8.92 ± 7.0 μg m-3,with 34%of samples exceeding the average value.Seasonally,BC was highest during the post-monsoon and winter periods(approximately 18 μg m-3) and lower in the premonsoon/monsoon seasons(approximately 6 μg m-3).The highest frequency(approximately 46%) observed for BC mass was in the interval from 5 to 10 μg m-3.However,during the post-monsoon season,the most common values(approximately 23%) were between 20 and 25 μg m-3.The nighttime concentrations of BC were approximately twice as much as the daytime values because of lower boundary layer heights at nighttime.The Angstrom exponent was significantly positively correlated(0.55) with ground-level BC concentrations,indicating the impact of BC on the columnar aerosol properties.The estimated mean absorption Angstrom exponent was 1.02 ± 0.08 μg m-3,indicating that the major source of BC was from fossil fuel combustion.Significant negative correlations between BC mass and meteorological parameters indicate a pronounced effect of atmospheric dynamics on the BC mass in this region.The highest mean BC mass concentration(18.1 ± 6.9 μg m-3) as a function of wind speed was under calm wind conditions(38%of the time). 展开更多
关键词 black carbon indo-gangetic plains absorption Angstr(o|¨)m exponent biomass fossil fuel
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Impact of Drought on Agriculture in the Indo-Gangetic Plain,India 被引量:2
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作者 Reshmita NATH Debashis NATH +2 位作者 Qian LI Wen CHEN Xuefeng CUI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第3期335-346,共12页
In this study, we investigate the spatiotemporal characteristics of drought in India and its impact on agriculture during the summer season (April-September). In the analysis, we use Standardized Precipitation Evapo... In this study, we investigate the spatiotemporal characteristics of drought in India and its impact on agriculture during the summer season (April-September). In the analysis, we use Standardized Precipitation Evapotranspiration Index (SPEI) datasets between 1982 and 2012 at the six-monthly timescale. Based on the criterion SPEI 〈 -1, we obtain a map of the number of occurrences of drought and find that the humid subtropical Upper Middle Gangetic Plain (UMGP) region is highly drought-prone, with an occurrence frequency of 40%-45%. This UMGP region contributes at least 18%-20% of India's annual cereal production. Not only the probability of drought, but the UMGP region has become increasingly drought-prone in recent decades. Moreover, cereal production in the UMGP region has experienced a gradual declining trend from 2000 onwards, which is consistent with the increase in drought-affected areas from 20%-25% to 50%-60%, before and after 2000, respectively. A higher correlation coefficient (-0.69) between the cereal production changes and drought-affected areas confirms that at least 50% of the agricultural (cereal) losses are associated with drought. While analyzing the individual impact of precipitation and surface temperature on SPEI at 6 month timescale [SPEI (6)] we find that, in the UMGP region, surface temperature plays the primary role in the lowering of the SPEI. The linkage is further confirmed by correlation analysis between SPEI (6) and surface temperature, which exhibits strong negative values in the UMGP region. Higher temperatures may have caused more evaporation and drying, which therefore increased the area affected by drought in recent decades. 展开更多
关键词 DROUGHT AGRICULTURE SPEI indo-gangetic plain temperature PRECIPITATION potential evapotranspiration
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Atmospheric particle-bound mercury in the northern Indo-Gangetic Plain region:Insights into sources from mercury isotope analysis and influencing factors
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作者 Junming Guo Lekhendra Tripathee +6 位作者 Shichang Kang Qianggong Zhang Jie Huang Chhatra Mani Sharma Pengfei Chen Rukumesh Paudyal Dipesh Rupakheti 《Geoscience Frontiers》 SCIE CAS CSCD 2022年第1期85-95,共11页
Lumbini is a world heritage site located in the southern plains region of Nepal, and is regarded as a potential site for evaluating transboundary air pollution due to its proximity to the border with India. In this st... Lumbini is a world heritage site located in the southern plains region of Nepal, and is regarded as a potential site for evaluating transboundary air pollution due to its proximity to the border with India. In this study, 82 aerosol samples were collected between April 2013 and July 2014 to investigate the levels of particulate-bound mercury(PBM) and the corresponding seasonality, sources, and influencing factors.The PBM concentration in total suspended particulate(TSP) matter ranged from 6.8 pg m^(-3) to351.7 pg m^(-3)(mean of 99.7 ± 92.6 pg m^(-3)), which exceeded the ranges reported for remote and rural sites worldwide. The Hg content(PBM/TSP) ranged from 68.2 ng g^(-1) to 1744.8 ng g^(-1)(mean of 446.9 ±312.7 ng g^(-1)), indicating anthropogenic enrichment. The PBM levels were higher in the dry season(i.e.,winter and the pre-monsoon period) than in the wet season(i.e., the monsoon period). In addition, the δ^(202) Hg signature indicated that waste/coal burning and traffic were the major sources of Hg in Lumbini during the pre-monsoon period. Meanwhile, precipitation occurring during photochemical processes in the atmosphere may have been responsible for the observed Δ^(199) Hg values in the aerosol samples obtained during the monsoon period. The PBM concentration was influenced mostly by the resuspension of polluted dust during dry periods and crop residue burning during the post-monsoon period. The estimated PBM deposition flux at Lumbini was 15.7 lg m^(-2) yr^(-1). This study provides a reference dataset of atmospheric PBM over a year, which can be useful for understanding the geochemical cycling of Hg in this region of limited data. 展开更多
关键词 Particle-bound mercury Seasonality Mercury isotopes Deposition flux indo-gangetic plain
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Translation Strategies of Red Tourism Terms in the Central Plains-Taking Red Central Plains as an Example
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作者 YUN Meng-nan 《Journal of Literature and Art Studies》 2024年第2期133-137,共5页
In recent years,the Red Tourism in Central Plains has gradually become a new type of thematic tourism form,which is an important carrier to carry out patriotism and revolutionary traditional education and carry forwar... In recent years,the Red Tourism in Central Plains has gradually become a new type of thematic tourism form,which is an important carrier to carry out patriotism and revolutionary traditional education and carry forward the national spirit.The translation of red tourism publicity is an important window for spreading Chinese culture,and the translation of professional terms is an important link in the red tourism publicity.How to spread the red culture of the Central Plains,glow the charm of the Central Plains culture,enhance the influence of the Central Plains culture,and spread the Central Plains culture to the world has become the mission of every child of the Central Plains.This paper adopts the case analysis method,combined with the specific and typical cases in“Red Central Plains”,and uses different translation strategies and methods to explore the difficulties and solutions of the translation of terms in the red tourism text. 展开更多
关键词 Red tourism Publicity translation Central plains culture translation strategy
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Seasonal Variation of Potential Source Locations of Atmospheric Particulates over the Indo-Gangetic Plain of India
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作者 Mohammad Hafizur Rahman V. P. Sharma +1 位作者 S. Kundu A. Datta 《Open Journal of Air Pollution》 2020年第1期1-10,共10页
Ambient particulate matter (PM2.5 and PM10) concentrations were measured during two different seasons (summer and winter) at three different locations of Gurugram which is located in the Indo-Gangetic plain of India. ... Ambient particulate matter (PM2.5 and PM10) concentrations were measured during two different seasons (summer and winter) at three different locations of Gurugram which is located in the Indo-Gangetic plain of India. The ambient concentrations of both PM2.5 and PM10 were higher during winter season (PM2.5: 261 μg·m-3;PM10: 440 μg·m-3) when compared to summer period (PM2.5: 114 μg·m-3;PM10: 202 μg·m-3). Potential Source Contribution Function (PSCF) analysis suggests significant seasonal variation in potential contributing locations of ambient PM2.5 over the study area. The PSCF analysis suggests that cross country transport of PM2.5 from Pakistan and Afghanistan significantly attributed to higher concentrations of PM2.5 at the study locations;whereas, PM2.5 emitted from locations in the south-western direction of the study sites attributed to the ambient PM2.5 concentrations at the study site during summer seasons. Further study is required to measure percentage contribution from different sectors and locations to the ambient particulate concentrations at the study site to develop sector specific mitigation plan. 展开更多
关键词 AMBIENT PARTICULATE MATTER indo-gangetic plain Region PSCF Analysis
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Soft Sediment Deformation Structures in the Sediment Deposits of Ganga River and Its Oxbow Lakes in Parts of Indo-Gangetic Plain: Implications for Quake Proxies and Paleoseismicity Tracking
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作者 Gufran Ali Mohd Sajid Mohammad Shamim Khan 《International Journal of Geosciences》 CAS 2023年第1期75-93,共19页
The Late Quaternary thick sedimentary fills of the Ganga basin predominantly consist of unconsolidated fluvial sandy deposits which are often intercalated with mud. These deposits at various places record the evidence... The Late Quaternary thick sedimentary fills of the Ganga basin predominantly consist of unconsolidated fluvial sandy deposits which are often intercalated with mud. These deposits at various places record the evidence of earthquakes, which occurred in the recent geological past. The evidence is contained and manifested in the form of Soft Sediment Deformation Structures (SSDSs). Saturated sediments/muds/soils are liquefied by earthquake tremors which either generate SSDS or produce structural discordance in the pre-existing sedimentary structures. The present study reports the occurrence of SSDS, e.g. load and associated flame structures, clastic dikes and sill structures, slump structures and sedimentary breccias, etc. from the Ganga River and adjacent oxbow lake sediment deposits. An attempt has been made to establish the origin of soft sediment structures of this region in accordance with its neotectonic history and in turn, identification of seismic structural proxies to delineate paleoseismic events in this region with futuristic implications. The preservation of soft sediment deformation structures in large numbers with multiple geomorphology and scale, in the river and adjoining lake sediments, is indicative of frequent earthquakes of high magnitude consequent to tectonic activism in the Himalayan region. 展开更多
关键词 Quaternary Sediments Flood plain Central Ganga Basin Sediment Dynamism Himalayan Uplift Paleoquakes
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Development Plan for Under- forest Economy of Henan Province Based on Central Plains Economic Region 被引量:3
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作者 Xiaodong ZHAO Yimin ZHAO 《Asian Agricultural Research》 2016年第2期34-38,共5页
Firstly,this paper analyzed current situations,major practice and existing problems of under-forest economy in Henan Province.Then,it made an in-depth discussion of guiding thought,principle and objectives,constructio... Firstly,this paper analyzed current situations,major practice and existing problems of under-forest economy in Henan Province.Then,it made an in-depth discussion of guiding thought,principle and objectives,construction task and safeguarding measures of the underforest economic development plan. Besides,it analyzed benefits of the under-forest economic development plan. By 2017,the area of underforest economic land will reach 1. 60 million hm2,create output value of 155. 2 billion yuan( accounting for more than 20% of forest output value),provide 3. 27 million jobs,and will greatly increase ecological carrying capacity of construction and development of the Central Plains Economic Region( CPER). 展开更多
关键词 WORDS Under-forest ECONOMY Plan Central plains Economic Region(CPER) Analysis HENAN PROVINCE
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Drought and Associated Impacts in the Great Plains of the United States—A Review 被引量:1
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作者 Jeffrey B. Basara Joanna N. Maybourn +4 位作者 Casey M. Peirano Jennifer E. Tate Parker J. Brown Jake D. Hoey Brandon R. Smith 《International Journal of Geosciences》 2013年第6期72-81,共10页
The Great Plains region of the United States is susceptible to drought of all kinds including meteorological/climatological, agricultural, hydrological, and socioeconomic. Drought conditions in the region span varying... The Great Plains region of the United States is susceptible to drought of all kinds including meteorological/climatological, agricultural, hydrological, and socioeconomic. Drought conditions in the region span varying spatial and temporal scales and the causes include: 1) certain synoptic conditions that favor drought such as mid-tropospheric ridging over the drought-affected area and a weak low-level jet;2) sea surface temperature anomalies and associated teleconnections;3) land-atmosphere coupling;and 4) anthropogenic effects. While drought can span as few as a couple of months, the most severe droughts can occur at the decadal scale such as the 1930s Dust Bowl, the worst drought in recent history from a societal standpoint. Such droughts in the Great Plains have widespread impacts on agriculture, water resources, human health, and the economy. 展开更多
关键词 DROUGHT GREAT plains UNITED States RAINFALL Precipitation
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Growth and Yield of Guar (Cyamopsis tetragonoloba L.) Genotypes under Different Planting Dates in the Semi-Arid Southern High Plains 被引量:1
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作者 Sudhir Singla Kulbhushan Grover +3 位作者 Sangamesh V. Angadi Sultan H. Begna Brian Schutte Dawn Van Leeuwen 《American Journal of Plant Sciences》 2016年第8期1246-1258,共13页
Guar is a drought and salt tolerant summer annual legume, which could be a potential alternative crop in the semi-arid Southern High Plains. Increased use of guar gum in oil industries has increased the demand of guar... Guar is a drought and salt tolerant summer annual legume, which could be a potential alternative crop in the semi-arid Southern High Plains. Increased use of guar gum in oil industries has increased the demand of guar globally. Planting date effects on stand establishment, physiological parameters, and yield formation of guar genotypes were investigated at the New Mexico State University’s Agricultural Science Center at Clovis, NM for two seasons (2014 and 2015). Four guar genotypes (HES 1123, Kinman, Lewis, and Matador) were tested under three planting dates (June 18, July 7, and July 22 in 2014;and June 18, July 6, and July 20 in 2015). Higher temperature and rainfall were recorded under mid-June planting than early-July and late-July plantings. Guar planted under mid-June had better stand establishment as shown by the higher number of plants m<sup>-2</sup>, better physiology as revealed by higher photosynthetic rate (P<sub>n</sub>), transpiration rate (T<sub>r</sub>), leaf area index (LAI), and SPAD values than early-July and late-July plantings. Guar planted under mid-June resulted in taller plants, and therefore, produced higher plant biomass than both of the July plantings. Yield attributing characteristics including clusters plant<sup>-1</sup>, pods plant<sup>-1</sup>, seeds plant<sup>-1</sup>, seed spod<sup>-1</sup>, 1000 seed weight, and harvest index (HI) were highest under mid-June planting followed by the early-July and late-July plantings, respectively. The mid-June planting increased seed yield by 26% and 55% over early-July and late-July (1399 vs. 1111 and 903 kg&middot;ha<sup>-1</sup>) plantings, respectively in 2014;while the same increase in 2015 was 51% and 243% (1308 vs. 868 and 381 kg&middot;ha<sup>-1</sup>), respectively. These results indicate that delaying planting beyond mid-June is detrimental to guar productivity. However, genotypes did not show any significant variation in their performance. Overall, warmer growing conditions and more precipitation under mid-June planting caused better growth and yield formation of guar genotypes. 展开更多
关键词 GUAR Planting Date Genotype Yield Southern High plains
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Great Plains公司采用亚麻荠生产航空生物燃料 被引量:3
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作者 钱伯章 《炼油技术与工程》 CAS 2010年第3期37-,共1页
继最近成功使用亚麻荠生产航空生物燃料之后,美国两大亚麻荠生产公司于2010年1月23日表示,将实施大型航空生物燃料项目。在美国,Great Plains公司将与BioJet公司合作,采用亚麻荠生产航空生物燃料。
关键词 航空生物燃料 Great plains 亚麻 胡麻 麻类作物 航空公司 航空运输企业
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The Palaeoclimate Variations in the Central Plains Since the Interstade of the Last Glacial Stage 被引量:1
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作者 XIAO Huaguo WU Xihao +3 位作者 JIANG Fuchu XUE Bin TIAN Guoqiang LIU Ke 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1998年第1期108-113,共6页
Through the study of a high-resolution loess record in the Central Plains, the short—term palaeoclimatic variations since the interstade of the last glacial stage have been discussed in this paper. The palaeoclimate ... Through the study of a high-resolution loess record in the Central Plains, the short—term palaeoclimatic variations since the interstade of the last glacial stage have been discussed in this paper. The palaeoclimate in the East Asian monsoon areas shows different variation patterns in summer and winter. A correlation of the palaeomonsoon records of loess with the δ18O records of the ice core and deep sea is made, and some of the causes for their differences are also discussed. 展开更多
关键词 palaeoclimate changes the Central plains last glacial stage
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Water use, growth and yield of green gram under rainfed upland crop sequences in Gangetic Plains of Indian sub-tropics
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作者 A. Zaman, S.K. Choudhuri( Regional Research Station, Old Alluvial Zone, Majhian, Kalyani-741 235, West Bengal, India) 《Journal of Geographical Sciences》 SCIE CSCD 2002年第3期301-304,共4页
A field experiment was conducted to study the effect of different crop sequences on water use, growth and yield of green gram (Vigna radiate (L) Wilezek) during 1992–93 and 1993–94 under rainfed upland condition in ... A field experiment was conducted to study the effect of different crop sequences on water use, growth and yield of green gram (Vigna radiate (L) Wilezek) during 1992–93 and 1993–94 under rainfed upland condition in Indo-Gangetic plains of West Bengal. Green gram sown in the month of March as pre-rainy (summer) season crop, as and when the winter crops vacated the land, produced highest dry matter of 372 gm-2 which was significantly highest in black gram-yellow sarson sequence. The results of the field experimentation revealed that green gram gave highest grain yield to the extent of 10.80 q/ha when sown after black gram (rainy season) followed by yellow sarson (winter season) while the crop produced 10.63 q/ha under sesame-yellow sarson sequence. Highest water use of 267 mm was achieved in green gram under black gram-yellow sarson sequence and the crop gave water use efficiency of 4.07 kg ha-1mm-1 under black gram-yellow sarson sequences. 展开更多
关键词 green gram water use crop sequences Gangetic plains (India)
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Study on Regional Image of Henan Province against the Background of Central Plains Rising
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作者 REN Jun 《Journal of Landscape Research》 2013年第4期47-48,共2页
Relevant theories of regional image were elaborated, and significance of regional image for the development of Henan Province was analyzed. On the basis of characteristic cultural resources in the local area, the ways... Relevant theories of regional image were elaborated, and significance of regional image for the development of Henan Province was analyzed. On the basis of characteristic cultural resources in the local area, the ways of building regional image of Henan were explored from the perspectives of orientation of cultural characteristics, regional image identification system and regional image evaluation. 展开更多
关键词 Central plains Economic Zone IMAGE of HENAN REGIONAL IMAGE
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IMPACTS OF SEA LEVEL RISE ON MAJOR PROJECTS AND URBAN DEVELOPMENT IN CHINA'S COASTAL PLAINS
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作者 yang Guishan Shi Yafeng(Naning Ihstitute of Goography and Lirnnology, CAS, Naning 210008 People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1996年第4期66-74,共9页
Due to the dual dris oftural and man-made factors, relative sea leverise in China's coastal plains can be 2 to 3 times over the global mean dunng thefirst half of the 21st Century, it will strongly whuence the van... Due to the dual dris oftural and man-made factors, relative sea leverise in China's coastal plains can be 2 to 3 times over the global mean dunng thefirst half of the 21st Century, it will strongly whuence the vanous coastal projectsand installations and the development of coastal dhes and towns. Research resultsshow that a 50-cm-nse in relative sea leve will cause maed decline in the functionof coastal defense and drainage projects and seriously endangur the functionalworking of the vast majority of coastal harbors. Meanwhile, it will also whuence thedevelopment of coastal dhes and towns throwi deterioratin water quality of thesource of urban water supply, increasing urban fiood risk and damagin seasidetounst resources etc.. Tianin, Shanghai and Guangzhou, the three most importancoastal dhes of China, will be Strongly affeded. 展开更多
关键词 China's coastal plains relative sea level rise projects and installations urban development
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Evaluation on Emergency Ability of Agricultural Envrironmental Pollution Incident in Central Plains Economic Zone
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作者 Chuai Xiaoming Yang Xiaoer +1 位作者 Zhou Haixia Zhang Yongling 《Meteorological and Environmental Research》 CAS 2015年第3期15-18,共4页
Abstract The level of emergency ability directly reflects response effect of an area to emergency. Taking Central Plains Economic Zone as re- search object, by documents retrieval, field survey, mechanism analysis and... Abstract The level of emergency ability directly reflects response effect of an area to emergency. Taking Central Plains Economic Zone as re- search object, by documents retrieval, field survey, mechanism analysis and logical reasoning, evaluation index system for emergency ability of ag- ricultural environmental pollution incident was established, which included 5 first grade indexes, 19 second grade indexes and 53 third grade inde- xes. By mechanism analysis and mathematical derivation, evaluation model for emergency ability of agricultural environmental pollution incident: I =m∑i=1∑j=1Pij, On this basis, four prefecture-level cities (A, B, C and D) of Central Plains Economic Zone were evaluated by using the index system and the evaluated model. The research could provide important theoretical reference for emergency ability construction of agricultural environmental pol- lution incident in Central Plains Economic Zone. 展开更多
关键词 Central plains Economic Zone Agricultural environmental pollution incident Emergency ability EVALUATION China
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Integration of GIS and F-Hydra Model for Aquifer Vulnerability Monitoring in the Afram Plains, Ghana
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作者 Asante Agyare Amos Tiereyangn Kabo-Bah +1 位作者 Bernard Trumah Bayel Abubakarr Sulaiman Jalloh 《Journal of Geoscience and Environment Protection》 2021年第3期222-248,共27页
Aquifer vulnerability is a critical issue across the entire globe due to the depletion of groundwater and escalation of pollution levels, which poses a detrimental effect on the natural environment. To ascertain this ... Aquifer vulnerability is a critical issue across the entire globe due to the depletion of groundwater and escalation of pollution levels, which poses a detrimental effect on the natural environment. To ascertain this contamination risk, an extensive study has been conducted to assess the aquifer vulnerability by using the F-hydra model. This paper presents the vulnerability technique for the theory and application of flow accumulation, land-use and hydraulic conductivity. The model was applied to a shallow aquifer in eastern Ghana’s Volta River Basin, with the results being compared to the standardised DRASTIC model. The model follows the aquifer vulnerability assessment concept of the source pathway receptor where flow accumulation represents the ponding areas with downward percolation of contaminant to the water table, land-use represents the human activities at the land surface, and hydraulic conductivity represents the driving force leading to the movement of contaminant. The results reveal that the moderate vulnerability region covers 51.55% (2598.12 km<sup>2</sup>) of the entire area. The high and low vulnerability regions cover a significant percentage of the area 1.13% (56.52 km<sup>2</sup>) and 47.32% (2384.93 km<sup>2</sup>), respectively. The final vulnerability index was largely influenced by the removal of the hydraulic conductivity and land-use parameters. The model was validated with nitrate concentration in drilled wells in the study area. The maps produced in this study could be utilised as a guide to vulnerability by policymakers, groundwater manager and planners aimed at preserving the integrity of this vulnerable resource. 展开更多
关键词 GIS VULNERABILITY AQUIFER Nitrate Contamination GROUNDWATER Afram plains
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Spatial Heterogeneity Analysis of PM2.5 Concentration in Central Plains Economic Region
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作者 Kaiguang Zhang Hongling Meng +1 位作者 Mingting Ba Yanmin Sun 《Journal of Geoscience and Environment Protection》 2020年第12期244-254,共11页
The research of the spatial heterogeneity of PM2.5 concentration in an area, is of great significance for understanding its regional spatial distribution structure, exploring the transmission relationship between regi... The research of the spatial heterogeneity of PM2.5 concentration in an area, is of great significance for understanding its regional spatial distribution structure, exploring the transmission relationship between regions, in order to formulate joint prevention and control measures within the entire area. Based on the daily monitoring data of PM2.5 concentration in the Central Plains Economic Region in 2019, this paper utilizes cluster analysis to divide the regional PM2.5 concentration into 5 classes, builds their spatial semi-variogram model, and then utilizes interpolation analysis method to study the regional overall distribution characteristics and transmission law. The results show that the PM2.5 concentration in the Central Plains Economic Region has a medium or higher spatial autocorrelation. The critical value of the overall PM2.5 concentration in the area is 150 μg/m3, as the overall PM2.5 concentration less than the value, the PM2.5 in a region mainly comes from local emissions, as the overall PM2.5 concentration higher than the value, the influence of spatial structure on the distribution of PM2.5 concentration is gradually obvious. PM2.5 has a certain degree of spatial transmission, which mainly includes two routes as Puyang-Xingtai and Puyang-Zhengzhou, and the transmission intensity of the former is greater than the latter. 展开更多
关键词 Cluster Analysis Semi-Variogram Spatial Heterogeneity Spatial Structure Central plains Economic Region
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Land Suitability Evaluation for Oil Palm (<i>Elaeis guineensis</i>Jacq.) in Coastal Plains of Southwest Cameroon
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作者 Georges Kogge Kome Fritz Oben Tabi +1 位作者 Roger Kogge Enang Francis Brice Tedou Silatsa 《Open Journal of Soil Science》 2020年第7期257-273,共17页
Declining yields in oil palm fresh fruit bunch (FFB) have been recorded over the past years in the coastal lowlands of southwest Cameroon and current actual yields are very low (<12 t FFB ha<sup><span styl... Declining yields in oil palm fresh fruit bunch (FFB) have been recorded over the past years in the coastal lowlands of southwest Cameroon and current actual yields are very low (<12 t FFB ha<sup><span style="white-space:nowrap;">&minus;</span>1</sup><span style="white-space:nowrap;">&bull;</span>yr<sup><span style="white-space:nowrap;">&minus;</span>1</sup>) compared to the potential yields (25 t FFB ha<sup><span style="white-space:nowrap;">&minus;</span>1</sup><span style="white-space:nowrap;">&bull;</span>yr<sup><span style="white-space:nowrap;">&minus;</span>1</sup>). One of the problems limiting optimum oil palm production is lack of detailed pedological information to guide plantation establishment and management. A land suitability evaluation was carried out for some major oil palm producing areas of southwest Cameroon to identify land qualities limiting optimal production. Thirteen sites (9 with sedimentary parent materials and 4 with volcanic parent material) were evaluated using a parametric method. Results indicate that climate was not a major limiting factor for oil palm production in coastal plains of southwest Cameroon. However, soil physical characteristics (mainly clayey texture and poor drainage) and soil fertility constitute limitations to oil palm production. Specifically, limitations in cation exchange capacity (CEC), base saturation (BS), organic carbon (OC) and pH were slight to moderate while K mole fraction was the most severe and the most limiting in all the sites. The fertility limitations were more pronounced in soils derived from sedimentary parent materials where 33% had limitations caused by soil pH and OC compared to none for volcanic soils. In addition, 77.8% of sedimentary soils had limitations caused by CEC compared to 25% for volcanic soils. Considering the overall suitability, soils derived from volcanic parent materials were potentially more suitable for oil palm cultivation ((S3)—50%, (S2)—50%) compared to sedimentary soils ((N)—11%, (S3)—78% and (S2)—11%). Based on the suitability classes of the different soils derived from dissimilar parent materials, appropriate site-specific soil management is needed to improve oil palm yields, especially with emphasis on K fertilization and improved soil water management. Plantation management in coastal plains of South West Cameroon therefore should factor in differences in soil parent material. 展开更多
关键词 Land Evaluation Oil Palm K Mole Fraction Soil Parent Material Coastal plain Soils
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Does Climatic Variability Influence Agricultural Land Prices under Differing Uses? The Texas High Plains Case
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作者 Rachna Tewari Jeff Johnson +2 位作者 Darren Hudson Chenggang Wang Dennis Patterson 《Natural Resources》 2013年第8期506-513,共8页
The Texas High Plains faces projections of increasing temperature and declining precipitation in the future on account of its semi-arid climate. This research evaluated the impact of climatic variability on agricultur... The Texas High Plains faces projections of increasing temperature and declining precipitation in the future on account of its semi-arid climate. This research evaluated the impact of climatic variability on agricultural land prices under different land uses in the Texas High Plains, employing the Ricardian approach of land climate pricing over a study period of 1991-2011. The results indicate that climatic variability had a greater impact on irrigated land prices as compared to dryland and ranchland. This study could be instrumental in predictive market analyses of rural land values in semi-arid economies which are vulnerable to future climate change. 展开更多
关键词 Climatic Variability DRYLAND IRRIGATED LAND LAND PRICES Ranchland Texas HIGH plains
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Gravity-Driven Listric Growth Fault and Sedimentation in the Lagoa do Peixe, Rio Grande do Sul Coastal Plain, Brazil
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作者 Bruno Silva da Fontoura Adelir José Strieder +1 位作者 Iran Carlos Stalliviere Corrêa Paulo Rogério Mendes 《Open Journal of Geology》 CAS 2024年第4期594-616,共23页
High frequency, high resolution GPR surveys are successfully applied to investigate near-surface stratification architecture of sedimentary units in coastal plains and to define their depositional conditions. However,... High frequency, high resolution GPR surveys are successfully applied to investigate near-surface stratification architecture of sedimentary units in coastal plains and to define their depositional conditions. However, low frequency GPR surveys to investigate fault-related depositional systems at greater depths are scarce. This survey was designed investigate a > 100 km long linear escarpment that controls the northwest margin of the Lagoa do Peixe, an important lagoon in Rio Grande do Sul Coastal Plain (RGSCP, Brazil). The traditional approach points that RGSCP was developed by juxtaposition of four lagoons/barrier systems as consequence of sea level changes;no deformational structure is admitted to exist before. The low frequency GPR (50 MHz, RTA antenna) and geological surveys carried out in the RGSCP showed the existence of a large, gravity-driven listric growth fault controlling the Lagoa do Peixe escarpment and hangingwall sedimentation. The radargrams in four subareas along the Lagoa do Peixe Growth Fault could be interpreted following the seismic expression of rift-related depositional systems. The radargrams enabled to distinguish three main lagoonal deposition radarfacies. The lower lagoonal radarfacies is a convex upward unit, thicker close to growth fault;the radarfacies geometry indicates that fault displacement rate surpasses the sedimentation rate, and its upper stratum is aged ~3500 <sup>l4</sup>C years BP. The second lagoonal radarfacies is a triangular wedge restricted to the lagoon depocenter, whose geometry indicates that fault displacement and the sedimentation rates kept pace. The upper lagoonal radarfacies is being deposited since 1060 ± 70 <sup>l4</sup>C years BP, under sedimentation rate higher than fault displacement rate. The results indicate that low frequency GPR surveys can help in investigating fault-related depositional systems in coastal zones. They also point to a new approach in dealing with RGSCP stratigraphy. 展开更多
关键词 GPR (Ground-Penetrating Radar) Growth Fault SEDIMENTATION Radarfacies Coastal plain
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