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Relationship between Regional Rainstorm Index and Flood Disaster Ratio of Crop 被引量:8
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作者 姜会飞 廖树华 +1 位作者 潘学标 候双双 《Agricultural Science & Technology》 CAS 2011年第3期429-434,共6页
According to the daily precipitation data in Beijing area from 1985 to 2008,rainstorm weather index (10.4-38.8 mm) and climate index (daily precipitation ≥27.5 mm) in Beijing area were obtained by using the deter... According to the daily precipitation data in Beijing area from 1985 to 2008,rainstorm weather index (10.4-38.8 mm) and climate index (daily precipitation ≥27.5 mm) in Beijing area were obtained by using the determination method of extreme climate event index recommended by IPCC. Based on rainstorm weather index,rainstorm climate index and national rainstorm standard,the number of rainstorm days and rainfall amount in past years were calculated,and the correlation of annual number of rainy days,rainstorm days,precipitation and rainstorm amount with the flood disaster ratio of crop was analyzed,and the results showed that annual number of rainy days and rainstorm days couldn't reflect flood disaster ratio of crop truly,while annual precipitation and rainstorm amount had obvious linear positive correlation with the flood disaster ratio of crop. In addition,the correlation degree between rainstorm amount calculated by regional climate index and flood disaster ratio of crop was the highest,so it was suggested that rainstorm amount calculated by regional rainstorm climate index could be used to predict and evaluate flood disaster. 展开更多
关键词 RAINSTORM Rainstorm index Number of rainstorm days Rainstorm amount Flood disaster
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Changes in human settlement environments and their drivers in valley cities located in arid and semi-arid regions:A case study of Lanzhou in Western China
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作者 Rong Zhu YouYan Jiang +1 位作者 Bo Wang YaHui Zhang 《Research in Cold and Arid Regions》 CSCD 2024年第3期149-158,共10页
Development of urban human settlement environments(HSEs)is an integral part of promoting high-quality and sustainable regional development and constructing a beautiful China.The city of Lanzhou,located at the geometri... Development of urban human settlement environments(HSEs)is an integral part of promoting high-quality and sustainable regional development and constructing a beautiful China.The city of Lanzhou,located at the geometric center of China,is the only provincial capital traversed by the Yellow River.Given the constraints posed by the valley topography and the need for economic development,the development of this HSE,which is located within an arid region,poses considerable challenges.Evidently,an understanding of the evolution of HSEs and drivers of changes in them contributes to high-quality,sustainable urban development in arid and semi-arid regions.An analytical model was developed using the parameters of relief degree of land surface,human comfort days,the land cover index,nighttime light index,and precipitation.This model was used in combination with population density and the gross domestic product to analyze the spatial distribution of Lanzhou's HSE and its drivers.The results showed that landscapes in Lanzhou underwent significant changes between 2000 and 2022,with an increase in building-up land(+0.946%),cultivated land(+0.134%),and forest land(+0.018%)and a decrease in grassland(-1.10%).There was significant outward expansion of the main urban zone of Lanzhou and of various county towns,with the increase in building-up land being most prominent.During this period,there were significant changes in the periphery of the core urban area and county towns in Lanzhou,with decreases moving from the urban center(the highest value)to the surrounding areas(Yongdeng County had the lowest value).The correlation between the HSE and population density grew stronger in Anning and Chengguan Districts but became weaker in Xigu and Qilihe Districts.Spatiotemporal variations in the HSE were primarily caused by climate change,followed by human activities,and were also influenced by the valley topography.Overall,the spatial distribution of population density and the HSE in Lanzhou demonstrated good consistency under the in-fluence of economic development and urbanization. 展开更多
关键词 Human settlement environment Vegetation index Nighttime light index Human comfort days
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THE SPATIOTEMPORAL CHARACTERISTICS OF LIGHT RAIN DAYS AND LOW CLOUD COVER UNDER HEAVY POLLUTION OVER SOUTH CHINA
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作者 符传博 丹利 +1 位作者 陈红 何鑫 《Journal of Tropical Meteorology》 SCIE 2017年第2期229-236,共8页
By using the data set of light rain days and low cloud cover at 51 stations in South China(SC), and the method of linear regression and correlative analysis, we analyze the spatiotemporal characteristics of the light ... By using the data set of light rain days and low cloud cover at 51 stations in South China(SC), and the method of linear regression and correlative analysis, we analyze the spatiotemporal characteristics of the light rain days and low cloud cover including annual variation and long-term seasonal change. The results are as follows:(1) The trends of light rain days and low cloud cover over SC are opposite(light rain days tended to decrease and low cloud cover tended to increase in the past 46 years). The value distributed in east is higher than that in west, and coastal area higher than inland area.(2) The regression coefficients of light rain days and low cloud cover during 1960-2005 are4.88 d/10 years and 1.14%/10 years respectively, which had all passed the 0.001 significance level.(3) Variations of light rain days are relatively small in spring and summer, but their contributions are larger for annual value than that of autumn and winter.(4) There are two regions with large values of aerosol optical depth(AOD), which distribute in central and southern Guangxi and Pearl River Delta(PRD) of Guangdong, and the value of AOD in PRD is up to 0.7.The aerosol index distributed in coastal area is higher than in the inland area, which is similar to the light rain days and low cloud cover over SC. Aerosol indexes in SC kept increasing with fluctuation during the past 27 years. The GDP of the three provinces in SC increased obviously during the past 28 years, especially in Guangdong, which exhibited that there is simultaneous correlation between light rain days with the variables of low cloud cover and release of aerosols over SC during 1960 to 2005. 展开更多
关键词 light rain days low cloud cover AOD Aerosol index South China
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大冶湖2000-2009年地表水质评价及污染趋势预测 被引量:24
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作者 鲁珍 李晔 +5 位作者 马啸 张亚东 黄柏龙 张猛 朱丽 刘成 《环境科学与技术》 CAS CSCD 北大核心 2012年第5期174-178,共5页
对大冶湖三部分水体2000-2009年的地表水水质监测数据进行分析,采用水质标识指数法对大冶湖水质进行评价;并依据灰色系统理论,建立灰色预测数学模型,通过已有的监测数据对模型进行精度检验,验证了该模型的准确性及有效性,运用该模型对... 对大冶湖三部分水体2000-2009年的地表水水质监测数据进行分析,采用水质标识指数法对大冶湖水质进行评价;并依据灰色系统理论,建立灰色预测数学模型,通过已有的监测数据对模型进行精度检验,验证了该模型的准确性及有效性,运用该模型对大冶湖未来5年水质变化趋势进行预测。结果表明:(1)2000-2009年三里七湖,内湖COD、BOD5、NH3-N和TP浓度均超出水质保护标准限值,外湖4项污染指标部分年份超标,其中,三里七湖水质最差,在2004、2005和2008 3个年份实际水质类别为劣Ⅴ类;(2)灰色模型预测结果表明,3个主要水体主要污染物:COD、BOD5、NH3-N和TP浓度基本呈上升趋势,仅三里七湖的TP、BOD5和外湖的NH3-N存在小幅下降。此预测结果对大冶湖水污染控制规划、污染物总量削减及湖泊保护等工作提供依据。 展开更多
关键词 大冶湖 标识指数 水质评价 灰色模型 预测
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大冶市街尘重金属污染评价及化学形态特征 被引量:13
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作者 韩晓涛 郭宇 +1 位作者 鲍征宇 周树达 《地球化学》 CAS CSCD 2012年第6期585-592,共8页
以矿冶城市大冶市为例,结合街尘pH及矿物相,研究矿山活动影响下的2个典型区(靠近矿区的铜绿山镇和相对远离矿区的大冶市区)街尘中重金属(Cd、Pb、Cu)污染现状及化学赋存形态。地累积指数显示,铜绿山镇重金属处于严重污染水平,大冶市区... 以矿冶城市大冶市为例,结合街尘pH及矿物相,研究矿山活动影响下的2个典型区(靠近矿区的铜绿山镇和相对远离矿区的大冶市区)街尘中重金属(Cd、Pb、Cu)污染现状及化学赋存形态。地累积指数显示,铜绿山镇重金属处于严重污染水平,大冶市区处于重污染水平,其中Cd和Cu相对于Pb污染较严重。重金属BCR形态表明,铜绿山镇Cd以可氧化态和可还原态为主,大冶市区Cd四态比例基本相同;Pb在铜绿山镇以残渣态和可氧化态为主,而在大冶市区以弱酸态和可氧化态为主;Cu在两研究区均以可氧化态为主。Pb和Cd生物活性较大,对环境危害较高,Cu相对较低。 展开更多
关键词 街尘 重金属 BCR形态 地累积指数 大冶
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欧拉反褶积法用于井中磁测数据反演与解释 被引量:13
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作者 习宇飞 刘天佑 +1 位作者 杨坤彪 陈石羡 《工程地球物理学报》 2008年第2期181-186,共6页
欧拉反褶积法是一种能自动估计场源位置和深度的位场反演方法,用于地面重力和磁法都有较好的效果。本文将欧拉反褶积法推广应用于井中磁测资料的反演解释,介绍了反演的基本原理和实现步骤,并设计理论模型探讨了影响反演结果的因素,最后... 欧拉反褶积法是一种能自动估计场源位置和深度的位场反演方法,用于地面重力和磁法都有较好的效果。本文将欧拉反褶积法推广应用于井中磁测资料的反演解释,介绍了反演的基本原理和实现步骤,并设计理论模型探讨了影响反演结果的因素,最后把它用在大冶铁矿某井磁测数据的反演解释,取得了较好的效果。 展开更多
关键词 欧拉反褶积 磁测 井中数据 构造指数 大冶铁矿
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近60年大冶市三里七湖重金属污染沉积记录 被引量:7
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作者 曾令晗 宁栋梁 +1 位作者 毛欣 陈旭 《地球环境学报》 CSCD 2014年第4期252-260,共9页
本文采用放射性核素Cs-137测年结合碳球粒定年方法,建立大冶市三里七湖浅孔岩芯的年代序列。基于沉积物中10种重金属元素、磁化率和粒度等多指标记录以及大冶市的社会经济统计资料,采用地质累积指数和主成分分析方法,重建了近60年大冶... 本文采用放射性核素Cs-137测年结合碳球粒定年方法,建立大冶市三里七湖浅孔岩芯的年代序列。基于沉积物中10种重金属元素、磁化率和粒度等多指标记录以及大冶市的社会经济统计资料,采用地质累积指数和主成分分析方法,重建了近60年大冶市三里七湖重金属污染演化历史。结果表明三里七湖生态环境演化可以分为三个主要阶段:1951年以前,重金属含量低,反映工农业发展水平较低、人为干扰少,湖泊生态环境处于自然演化阶段;20世纪50年代以来,流域工农业活动发展加快导致重金属富集,尤其是1984年以后,重金属富集进一步加剧;2000年以来Zn、Cd、Ni、Fe、Cr等元素的含量仍呈升高态势,而Cu和Pb含量下降,反映人为活动干扰仍然十分强烈,同时冶炼技术进步和环境治理可能减少重金属污染。相关分析结果显示重金属地质累积指数与工业和农业产值显著相关,且与工业产值相关系数更高。这表明工农业活动引起的重金属输入是三里七湖重金属污染的诱因,其中工业活动影响更大。 展开更多
关键词 湖泊沉积物 重金属污染 地质累积指数 大冶市
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Spatial and temporal patterns of drought in Zambia 被引量:3
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作者 Brigadier LIBANDA ZHENG Mie Chilekana NGONGA 《Journal of Arid Land》 SCIE CSCD 2019年第2期180-191,共12页
Drought acutely affects economic sectors, natural habitats and communities. Understanding the past spatial and temporal patterns of drought is crucial because it facilitates the forecasting of future drought occurrenc... Drought acutely affects economic sectors, natural habitats and communities. Understanding the past spatial and temporal patterns of drought is crucial because it facilitates the forecasting of future drought occurrences and informs decision-making processes for possible adaptive measures. This is especially important in view of a changing climate. This study employed the World Meteorological Organization(WMO)-recommended standardized precipitation index(SPI) to investigate the spatial and temporal patterns of drought in Zambia from 1960 to 2016. The relationship between the occurrence of consecutive dry days(CDD; consecutive days with less than 1 mm of precipitation) and SPI was also investigated. Horizontal wind vectors at 850 hPa during the core of the rainy season(December–February)were examined to ascertain the patterns of flow during years of extreme and severe drought; and these were contrasted with the patterns of flow in 2007, which was a generally wet year. Pressure vertical velocity was also investigated. Based on the gamma distribution, SPI successfully categorized extremely dry(with a SPI value less than or equal to –2.0) years over Zambia as 1992 and 2015, a severely dry(–1.9 to –1.5) year as 1995, moderately dry(–1.4 to –1.0) years as 1972, 1980, 1987, 1999 and 2005, and 26 near normal years(–0.9 to 0.9). The occurrence of CDD was found to be strongly negatively correlated with SPI with a coefficient of –0.6. Further results suggest that, during wet years, Zambia is influenced by a clockwise circulating low-pressure zone over the south-eastern Angola, a second such zone over the northern and eastern parts, and a third over the Indian Ocean. In stark contrast, years of drought were characterized by an anti-clockwise circulating high-pressure zone over the south-western parts of Zambia,constraining precipitation activities over the country. Further, wet years were characterized by negative pressure vertical velocity anomalies, signifying ascending motion; while drought years were dominated by positive anomalies, signifying descending motion, which suppresses precipitation. These patterns can be used to forecast drought over Zambia and aid in strategic planning to limit the potential damage of drought. 展开更多
关键词 standardized PRECIPITATION index patterns of DROUGHT consecutive DRY dayS vertical velocity GAMMA distribution RAINFALL
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大冶诺兰达工艺简介及试生产实践 被引量:3
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作者 王建新 《有色冶炼》 1999年第5期11-12,42,共3页
介绍大冶诺兰达生产工艺、操作过程,总结各项技术参数与工艺特点以及达产考核情况,并就生产中有关问题作了初步探讨。
关键词 诺兰达炉 熔炼 操作技术 工艺指标 炼铜
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Assessing the evidence for weight loss strategies in people with and without type 2 diabetes 被引量:2
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作者 Peter Clifton 《World Journal of Diabetes》 SCIE CAS 2017年第10期440-454,共15页
This review will examine topical issues in weight loss and weight maintenance in people with and without diabetes. A high protein, low glycemic index diet would appear to be best for 12-mo weight maintenance in people... This review will examine topical issues in weight loss and weight maintenance in people with and without diabetes. A high protein, low glycemic index diet would appear to be best for 12-mo weight maintenance in people without type 2 diabetes. This dietary pattern is currently beingexplored in a large prevention of diabetes intervention. Intermittent energy restriction is useful but no better than daily energy restriction but there needs to be larger and longer term trials performed. There appears to be no evidence that intermittent fasting or intermittent severe energy restriction has a metabolic benefit beyond the weight loss produced and does not spare lean mass compared with daily energy restriction. Meal replacements are useful and can produce weight loss similar to or better than food restriction alone. Very low calorie diets can produce weight loss of 11-16 kg at 12 mo with persistent weight loss of 1-2 kg at 4-6 years with a very wide variation in long term results. Long term medication or meal replacement support can produce more sustained weight loss. In type 2 diabetes very low carbohydrate diets are strongly recommended by some groups but the long term evidence is very limited and no published trial is longer than 12 mo. Although obesity is strongly genetically based the microbiome may play a small role but human evidence is currently very limited. 展开更多
关键词 Protein Glycemic index Very low calorie diet Very low carbohydrate diet Low fat diets Intermittent energy restriction Alternate day fasting
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<i>Bradyrhizobium japonicum</i>Inoculation and Phosphorus Supplementation on Growth and Chlorophyll Accumulation in Soybean (<i>Glycine max</i>L.) 被引量:1
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作者 Eutropia V. Tairo Patrick A. Ndakidemi 《American Journal of Plant Sciences》 2013年第12期2281-2289,共9页
A field and glasshouse experiment was conducted to study the effect of B. japonicum inoculation and phosphorus supplementation on growth and leaf chlorophyll content in soybean. The treatments consisted of B. japonicu... A field and glasshouse experiment was conducted to study the effect of B. japonicum inoculation and phosphorus supplementation on growth and leaf chlorophyll content in soybean. The treatments consisted of B. japonicum inoculation (with & without), phosphorus supplementation at the levels of 0, 20, 40 and 80 kgP·ha-1. Both treatments were replicated four times in a split plot design. The following parameters were measured: plant height (cm), number leaves per plant, number of days to 50% flowering, number of days to 50% pod formation, stem girth and leaf area (LA). Results showed that inoculation with B. japonicum significantly increased plant height, number of leaves, leaf chlorophyll content, stem girth, leaf area (LA) and leaf area index (LAI). However, Phosphorus supplementation had significant effects in some parameters measured. The use of effective strain of B. japonicum and phosphorus supplementation was an efficient way of enhancing the growth of soybean. 展开更多
关键词 dayS to 50% Flowering dayS to 50% Pod Formation Legumes PLANT Height LEAF Area (LA) LEAF Area index (LAI) Number of Leaves per PLANT Stem GIRTH
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Source analysis and risk evaluation of heavy metal in the river sediment of polymetallic mining area:Taking the Tonglüshan skarn type Cu-Fe-Au deposit as an example,Hubei section of the Yangtze River Basin,China 被引量:1
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作者 Jing Wang Xin-xin Zhang +5 位作者 Ai-fang Chen Bo Wang Qi-bin Zhao Guan-nan Liu Xiao Xiao Jin-nan Cao 《China Geology》 CAS 2022年第4期649-661,共13页
In this paper,25 sampling points of overlying deposits in Tonglushan mining area,Daye City,Hubei Province,China were tested for heavy metal content to explore pollution characteristics,pollution sources and ecological... In this paper,25 sampling points of overlying deposits in Tonglushan mining area,Daye City,Hubei Province,China were tested for heavy metal content to explore pollution characteristics,pollution sources and ecological risks of heavy metals in sediments.A geo-accumulation index method was used to evaluate the degree of heavy metal pollution in the sediment.The mean sediment quality guideline quotient was used for evaluating the ecological risk level of heavy metal in the sediment.And a method of correlation analysis,clustering analysis,and principal component analysis was used for preliminary analysis on the source of heavy metal in the sediment.It was indicated that there was extremely heavy metal pollution in the sediment,among which Cd was extremely polluted,Cu strongly contaminated,Zn,As,and Hg moderately contaminated,and Pb,Cr,and Ni were slightly contaminated.It was also indicated by the mean sediment quality guideline-quotient result that there was a high ecological risk of heavy metals in the sediment,and 64%of the sample sites had extremely high hidden biotoxic effects.For distribution,the contamination of branches was worse than that of the main channel of Daye Dagang,and the deposition of each heavy metal was mainly influenced by the distance from this sample site to the sewage draining exit of a tailings pond.The source analysis showed that the heavy metals in the sediment come from pollution discharging of mining and beneficiation companies,tailings ponds,smelting companies,and transport vehicles.In the study area,due to the influence of heavy metal discharging from these sources,the ecotoxicity of heavy metals in the sediment was extremely high,and Cd was the most toxic pollutant.The research figured out the key restoration area and elements for ecological restoration in the sediment of the Tonglüshan mining area,which could be referenced by monitoring and governance of heavy metal pollution in the sediment of the polymetallic mining area. 展开更多
关键词 Sediment Heavy metal pollution Ecological risks Geo-accumulation index method Sediment quality guideline-quotient Cluster analysis Principal component analysis Skarn-type Ecological environment survey Tonglüshan daye Lake China
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基于水污染指数法的大冶湖水质评价 被引量:4
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作者 刘子国 曹阳 杨雪芬 《湖北理工学院学报》 2021年第2期13-16,共4页
为进一步了解大冶湖的水质现状,运用水污染指数法(Water Pollution Index,WPI)评价了2020年大冶湖大桥、磊山湖心、大冶湖闸3个断面的水质。结果表明,磊山湖心WPI全年平均值最小,水质明显优于另2个断面。对比同一断面不同月份的WPI,大... 为进一步了解大冶湖的水质现状,运用水污染指数法(Water Pollution Index,WPI)评价了2020年大冶湖大桥、磊山湖心、大冶湖闸3个断面的水质。结果表明,磊山湖心WPI全年平均值最小,水质明显优于另2个断面。对比同一断面不同月份的WPI,大冶湖监测断面5—6月份的水质是一年当中最差的;2—3月份水质是一年当中最好的。这可能是5—6月份雨水充沛,将面源污染物冲刷至大冶湖中所致。 展开更多
关键词 大冶湖 水污染指数 水质
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Mapping desertification potential using life cycle assessment method: a case study in Lorestan Province, Iran
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作者 Abolfazl RANJBAR Somayeh HEYDARNEJAD +1 位作者 Sayed H MOUSAVI Roohallah MIRZAEI 《Journal of Arid Land》 SCIE CSCD 2019年第5期652-663,共12页
In recent year,desertification has become one of the most important environmental hazards all over the world,especially in developing countries such as Iran.Understanding the factors impacting on desertification and i... In recent year,desertification has become one of the most important environmental hazards all over the world,especially in developing countries such as Iran.Understanding the factors impacting on desertification and identifying the regions with high desertification potential are essential to control this phenomenon(i.e.,desertification).The life cycle assessment(LCA)method is essential in assessing the desertification of ecosystems,especially for susceptible ecosystems with high degradation risks.The aim of the present study was to evaluate the desertification potential of Lorestan Province,Iran,based on the LCA method.We selected aridity,fire and dust as three indicators of desertification and collected data from 2000 to 2015.We divided the study area into 6 types of ecoregions according to the climate types(arid,semi-arid and dry sub-humid)and dominant species(Quercus brantii and Astragalus adscendens),and calculated the characteristic factor(CF)of each indicator(aridity,fire and dust)by combining the indicator layers and ecoregion layer of the study area.In a given ecoregion,the sum of CF values of aridity,dust and fire indicators represents the life cycle inventory(LCI)desertification value(the higher the LCI value,the greater the desertification potential).Then,we obtained the desertification potential map by combining and overlapping the ecoregions and the normalized indicators based on the LCA method.Aridity and fire exhibit significant impacts on desertification in the study area compared with dust.In the study area,semi-arid ecoregion with Quercus brantii as the dominant species is the largest ecoregion,while arid ecoregion with Quercus brantii as the dominant species is the smallest ecoregion.Arid ecoregion with Astragalus adscendens as the dominant species(LCI desertification value of 1.99)and dry sub-humid ecoregion with Quercus brantii as the dominant species(LCI desertification value of 0.79)show the highest and lowest desertification potentials,respectively.Furthermore,arid ecoregion with Quercus brantii as the dominant species also has a higher LCI desertification value(1.89),showing a high desertification potential.These results suggest the necessity of proper management and appropriate utilization in these ecoregions.In general,assessing desertification potential using the LCA method on a local and regional scale can possibly provide a new methodology for identifying and protecting areas with high degradation risks. 展开更多
关键词 life cycle assessment characterization factor DESERTIFICATION POTENTIAL ARIDITY index fire risk DUSTY dayS Lorestan PROVINCE
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Spatially Explicit Modeling of Long-Term Drought Impacts on Crop Production in Austria
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作者 Franziska Strauss Elena Moltchanova Erwin Schmid 《American Journal of Climate Change》 2013年第3期1-11,共11页
Droughts have serious and widespread impacts on crop production with substantial economic losses. The frequency and severity of drought events may increase in the future due to climate change. We have developed three ... Droughts have serious and widespread impacts on crop production with substantial economic losses. The frequency and severity of drought events may increase in the future due to climate change. We have developed three meteorological drought scenarios for Austria in the period 2008-2040. The scenarios are defined based on a dry day index which is combined with bootstrapping from an observed daily weather dataset of the period 1975-2007. The severity of long-term drought scenarios is characterized by lower annual and seasonal precipitation amounts as well as more significant temperature increases compared to the observations. The long-term impacts of the drought scenarios on Austrian crop production have been analyzed with the biophysical process model EPIC (Environmental Policy Integrated Climate). Our simulation outputs show that—for areas with historical mean annual precipitation sums below 850 mm— already slight increases in dryness result in significantly lower crop yields i.e. depending on the drought severity, between 0.6% and 0.9% decreases in mean annual dry matter crop yields per 1.0% decrease in mean annual precipitation sums. The EPIC results of more severe droughts show that spring and summer precipitation may become a limiting factor in crop production even in regions with historical abundant precipitation. 展开更多
关键词 LONG-TERM DROUGHT Modeling Dry day index BIOPHYSICAL IMPACTS Spatial Variability EPIC Austria
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黄石大冶湖生态新区核心区土壤重金属元素质量评价 被引量:4
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作者 朱柳琴 杨伟卫 +4 位作者 卢鹏 沈军 刘徽 闫芳 王宇 《资源环境与工程》 2020年第3期366-373,共8页
以表层土壤为研究对象,通过测定Zn、Ni、Cd、Cu、Cr、Pb、As、Hg等8种重金属元素质量分数,采用一类建设用地土壤风险筛选值,利用“单因子指数法”和“内梅罗综合指数法”对土壤重金属质量进行评价,评价结果表明核心区建设用地整体土壤... 以表层土壤为研究对象,通过测定Zn、Ni、Cd、Cu、Cr、Pb、As、Hg等8种重金属元素质量分数,采用一类建设用地土壤风险筛选值,利用“单因子指数法”和“内梅罗综合指数法”对土壤重金属质量进行评价,评价结果表明核心区建设用地整体土壤环境质量良好,适宜作为工程建设用地。 展开更多
关键词 土壤重金属 质量评价 单因子指数法 内梅罗综合指数法 黄石大冶湖生态新区核心区
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Effect of phenophase based irrigation schedules on growth, yield and quality of baby corn (Zea mays L.)
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作者 H. K. Shivakumar B. K. Ramachandrappa +2 位作者 H. V. Nanjappa   Mudalagiriyappa 《Agricultural Sciences》 2011年第3期267-272,共6页
The field experiment was conduced at the Agronomy Field Unit, Main Research Station, University of Agricultural Sciences, Hebbal, Bangalore, India during 2002 and 2003 to study the effect of irrigation schedules on gr... The field experiment was conduced at the Agronomy Field Unit, Main Research Station, University of Agricultural Sciences, Hebbal, Bangalore, India during 2002 and 2003 to study the effect of irrigation schedules on growth, yield and quality of baby corn. The soil of the experimental site was red sandy loam in texture with neutral reaction. The experiment was laid out in a randomized complete block design with three replications. There were seven treatments of irrigation schedules based on IW/CPE ratio of 0.6 and 1.0 during different phenophases of baby corn. The results of the experiment revealed that the baby corn dry matter was significantly higher (75.57 g.plant–1) with higher green fodder yield of 43.47 t.ha–1 due to irrigation scheduled at IW/CPE ratio of 1.0 followed by moisture stress at early stage (I3). Irrigations scheduled at IW/CPE ratio of 1.0 registered significantly higher baby corn yield of 6.60 t.ha–1 followed by the delayed irrigation at early stage of 10 - 25 DAS. Significantly higher crude protein, phosphorus, potassium and lower reducing sugars and ascorbic acid content of baby corn was recorded under IW/CPE ratio of 1.0. Delayed irrigation at 0.6 IW/CPE ratio through-out produced baby corn with higher taste and juiciness. The total crop water use ranged from 294.10 to 469.10 mm, respectively under continuously delayed irrigation at 0.6 IW/CPE ratio and frequent irrigation at IW/CPE ratio of 1.0 which also recorded higher water use efficiency. 展开更多
关键词 BABY CORN Irrigation SCHEDULE IW/CPE Ratio Yield Soil Moisture Stress day index
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Optimal Scheduling of Regional Integrated Energy Systems Considering Hybrid Demand Response
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作者 Ganyun Lyu Bin Cao +3 位作者 Dexiang Jia Nan Wang Jun Li Guangyu Chen 《CSEE Journal of Power and Energy Systems》 SCIE EI CSCD 2024年第3期1208-1219,共12页
Flexible load can optimize the load curve,which is an important means to promote renewable energy consumption.The peculiarities of electricity,heat,cooling and gas loads are analyzed in this paper,considering the fuzz... Flexible load can optimize the load curve,which is an important means to promote renewable energy consumption.The peculiarities of electricity,heat,cooling and gas loads are analyzed in this paper,considering the fuzzy degree of human perception for water temperature,and the characteristic model of hot water load is established.Considering the fuzzy degree of human perception of ambient temperature,the characteristic model of cooling load is established by using PMV and PPD index.Meanwhile,considering four combinations of cut load,translatable load,transferable load and alternative load,and considering the coupling relationship of composite parts,different response models of load are established respectively.With the minimum cost of the system,including operation and compensation costs as the objective function,the optimization scheduling model of the regional integrated energy system is established,and the Gurobi solver is used for simulation analysis to solve the optimal output and load response curve of each piece of equipment.The results show that the load curve can be optimized,the flexible regulation ability of the regional integrated energy system can be enhanced,the energy loss of the system can be reduced,and the wind power consumption ability of the system can be increased by considering the integrated demand response. 展开更多
关键词 Alternative load day ahead optimal scheduling integrated demand response PMV and PPD index regional integrated energy system
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Summer maize LAI retrieval based on multi-source remote sensing data
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作者 Fangjiang Pan Jinkai Guo +5 位作者 Jianchi Miao Haiyu Xu Bingquan Tian Daocai Gong Jing Zhao Yubin Lan 《International Journal of Agricultural and Biological Engineering》 SCIE 2023年第2期179-186,共8页
Leaf Area of Index(LAI)refers to half of the total leaf area of all crops per unit area.It is an important index to represent the photosynthetic capacity and biomass of crops.To obtain LAI conditions of summer maize i... Leaf Area of Index(LAI)refers to half of the total leaf area of all crops per unit area.It is an important index to represent the photosynthetic capacity and biomass of crops.To obtain LAI conditions of summer maize in different growth stages quickly and accurately,further guiding field fertilization and irrigation.The Unmanned aerial vehicles(UAV)multispectral data,growing degree days,and canopy height model of 2020-2021 summer maize were used to carry out LAI inversion.The vegetation index was constructed by the ground hyperspectral data and multispectral data of the same range of bands.The correlation analysis was conducted to verify the accuracy of the multispectral data.To include many bands as possible,four vegetation indices which included R,G,B,and NIR bands were selected in this study to test the spectral accuracy.There were nine vegetation indices calculated with UAV multispectral data which were based on the red band and the near-infrared band.Through correlation analysis of LAI and the vegetation index,vegetation indices with a higher correlation to LAI were selected to construct the LAI inversion model.In addition,the Canopy Height Model(CHM)and Growing degree days(GDD)of summer maize were also calculated to build the LAI inversion model.The LAI inversion of summer maize was carried out based on multi-growth stages by using the general linear regression model(GLR),Multivariate nonlinear regression model(MNR),and the partial least squares regression(PLSR)models.R²and RMSE were used to assess the accuracy of the model.The results show that the correlation between UAV multispectral data and hyperspectral data was greater than 0.64,which was significant.The Wide Dynamic Range Vegetation Index(WDRVI),Normalized Difference Vegetation Index(NDVI),Ratio Vegetation Index(RVI),Plant Biochemical Index(PBI),Optimized Soil-Adjusted Vegetation Index(OSAVI),CHM and GDD have a higher correlation with LAI.By comparing the models constructed by the three methods,it was found that the PLSR has the best inversion effect.It was based on OSAVI,GDD,RVI,PBI,CHM,NDVI,and WDRVI,with the training model’s R²being 0.8663,the testing model’s R²being 0.7102,RMSE was 1.1755.This study showed that the LAI inversion model based on UAV multispectral vegetation index,GDD,and CHM improves the accuracy of LAI inversion effectively.That means the growing degree days and crop population structure change have influenced the change of maize LAI certainly,and this method can provide decision support for maize growth monitoring and field fertilization. 展开更多
关键词 MAIZE UAV multispectral leaf area of index growing degree day canopy height model vegetation index
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Interactive Effects of Potassium and Phosphorus on Phenology and Grain Yield of Sunflower in Northwest Pakistan 被引量:6
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作者 AMANULLAH M.W.KHAN 《Pedosphere》 SCIE CAS CSCD 2010年第5期674-680,共7页
Potassium(K) and phosphorus(P) applications improve growth,increase yield and yield components of sunflower(Helianthus annuus L.) on K and P deficient soils in Northwest Pakistan.A field experiment was conducted using... Potassium(K) and phosphorus(P) applications improve growth,increase yield and yield components of sunflower(Helianthus annuus L.) on K and P deficient soils in Northwest Pakistan.A field experiment was conducted using sunflower cv.Hysun-33 at the New Developmental Research Farm of KPK Agricultural University,Peshawar,Pakistan,during summer 2006.The experimental design was a randomized complete block in split plot arrangements,with six levels of K(0,25,50,75,100,and 125 kg K ha-1) as main plots and four levels of P(0,45,90,and 135 kg P ha-1) as sub-plots with three replications.Sunflower yield and yield components responded positively to K and P fertilization but the magnitude of response varied with the levels of K and P.Days to flowering and maturity,grains per head,1000-grain weight,shelling percentage,and grain yield increased tremendously in the K and P-fertilized plots as compared to the control with no K and P applied.The combined application of 100 kg K and 45 kg P ha-1 significantly increased yield components,grain yield,harvest index,and shelling percentage of sunflower,suggesting that 100 kg K ha-1 in combination with 45 kg P ha-1 could maximize productivity of sunflower planted after wheat on the K and P deficient soils in the study area. 展开更多
关键词 days to flowering days to maturity harvest index soil yield components
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