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Analysis of the Influencing Factors of Changes in Foxtail Millet Planting Area in Hebei Province 被引量:2
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作者 Meng LIU Yu ZHAO +3 位作者 Fei LIU Shunguo LI Guirong WANG Xinshi ZHANG 《Asian Agricultural Research》 2013年第3期30-34,共5页
Since reform and open to the outside world,foxtail millet planting area in Hebei Province has constantly reduced,and its planting region has changed from the whole province into some regions,with obvious changes. In t... Since reform and open to the outside world,foxtail millet planting area in Hebei Province has constantly reduced,and its planting region has changed from the whole province into some regions,with obvious changes. In this paper,by using qualitative and quantitative approaches like chart analysis,summarizing,Delphi method and osculating value model,the influencing factors of changes in millet growing region in Hebei Province were studied. The results showed that the changes of millet planting area were closely related to many factors,such as little investment in scientific research,weak policy support,a single consumer product demand,the rapid development of other staple crops, labor migration,relatively low comparative effectiveness and physiological characteristics of the millet itself. Then some suggestions were put forward,such as increasing research support,strengthening scientific research strength,researching and developing deeply processed products, expanding consumer groups,improving millet policy support,providing subsidies for planting the improved varieties,researching and developing various types of machinery,and increasing millet production technology training. 展开更多
关键词 MILLET area CHANGES Influencing FACTORS Osculating
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Metabasic Dyke Swarms in a High-Grade Metamorphic Terrane——A Case Study in the Taipingzhai-Jinchangyu Area,Eastern Hebei Province
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作者 Chen Manyun Changchun College of Geology Zhang Zhongmin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1990年第4期427-441,467,共16页
Geological and petrological studies indicate that three phases of metabasic dykes are present in theTaipingzhai-Jinchangyu area within the high-grade metamorphic terrane of eastern Hebei. Garnet andhornblende in metab... Geological and petrological studies indicate that three phases of metabasic dykes are present in theTaipingzhai-Jinchangyu area within the high-grade metamorphic terrane of eastern Hebei. Garnet andhornblende in metabasic dykes of the second and third phases occur separately, forming two mineral aggregateareas gl+cpx+pl±hy and hb+cpx+pl-hy. P_(H_2O) in the rocks appears to be the main factor controlling theformation of the two aggregate areas. Both were formed simultaneously at the same metamorphic temperature. The second-phase basic dykes underwent metamorphism of pyroxene-granulite facies at a temperature ofsome 825C: later the dykes, together with the third-phase basic dykes experienced metamorphism ofamphibole-granulite facies at a temperature of about 750C under pressure of 0.9GPa. 展开更多
关键词 A Case Study in the Taipingzhai-Jinchangyu area eastern hebei province Metabasic Dyke Swarms in a High-Grade Metamorphic Terrane
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Effects of Different Modes of Returning Farmland to Forest on Physicochemical Properties of Soil in Bashang Area of Northern Hebei Province
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作者 Yue YANG Yitian YANG +2 位作者 Zhiyong WU Caiwu WU Yongjiao HAN 《Meteorological and Environmental Research》 CAS 2020年第4期98-102,共5页
[Objective]The research aimed to understand the change rules of physicochemical properties of soil in the different modes of returning farmland to forest.[Method]The physicochemical properties of soil in three differe... [Objective]The research aimed to understand the change rules of physicochemical properties of soil in the different modes of returning farmland to forest.[Method]The physicochemical properties of soil in three different types of returning farmland to forest(Hippophae rhamnoides Linn.forest,Caragana korshinskii forest and Ulmus pumila L.forest)were analyzed by taking the enclosed grassland as comparison in Bashang area of northern Hebei Province.[Result]The results showed that there were significant differences among different types.Order of the bulk density of soil:H.rhamnoides Linn.forest(1.17 g/cm^3)<U.pumila L.forest(1.24 g/cm^3)<C.korshinskii forest(1.26 g/cm^3)<enclosed grassland(1.61 g/cm^3);order of the total porosity of soil:H.rhamnoides Linn.forest(55.29%)>U.pumila L.forest(52.55%)>C.korshinskii forest(51.93%)<enclosed grassland(38.85%);order of the organic matter content of soil:H.rhamnoides Linn.forest(3.191%)>C.korshinskii forest(3.128%)>U.pumila L.forest(2.804%)>enclosed grassland(2.536%).[Conclusion]After returning farmland to forest,vegetation played a positive role in physicochemical properties of soil.There were significant differences in physicochemical properties of soil among different modes of returning farmland to forest,and the improvement effect of H.rhamnoides Linn.forest on physicochemical properties of soil was the best. 展开更多
关键词 Returning farmland to forest Physicochemical properties of soil Bashang area of northern hebei province
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The Activity of H_2O, Fugacity of O_2 and Variation of Their Chemical Potential During Metamorphic Peak of the Granulite Complex Near Taipingzhai-Louzishan Region, East Hebei Province
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作者 卢良兆 董永胜 周喜文 《Chinese Journal Of Geochemistry》 EI CAS 2001年第2期97-107,共11页
The thermodynamic calculation of dehydration reacton suggests very low activity of H\-2O during metamorphic peak of the Archaean granulite complex in the region studied.The a\-\{H\-2O\} values for Al\|rich gneiss and ... The thermodynamic calculation of dehydration reacton suggests very low activity of H\-2O during metamorphic peak of the Archaean granulite complex in the region studied.The a\-\{H\-2O\} values for Al\|rich gneiss and hypersthene biotite gneiss\|granulite in the Taipingzhai region are usually between 0.10 and \{0.20\},and those in the Louzishan region are \{0.15\}-\{0.25\}. The fugacity of O\-2 in terms of lgf\-\{O\-2\} in the whole region ranges from -8 to -14. The average coefficients of (μ\-\{H\-2O\}/X\+\{Bt\}\-\{Mg\}) and (μ\-\{O\-2\}/X\+\{Bt\}\-\{Mg\}) in the Taipingzhai region are \{-0.293\} and \{-1.60\} respectively,and those in the Louzishan region are \{-0.364\} and \{-1.420\}. The activity of H\-2O is very low in the whole region, but its values and other data mentioned above are considerably constant from place to place within a given region, even in rocks of different lithological characters. However, they show a certain gradient between different regions. Such characteristics are compatible with the genetic mechanism known as \!carbonic metamorphism" put forward by Newton et al.,i.e., the a\-\{H\-2O\} during the peak stage is controlled by permeation of pervasive CO\-2 influx of the mantle source,and shows features of external buffering. 展开更多
关键词 逸出氧 化学势 河北 麻粒岩 变质作用 水力学
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The Analysis of Limitation of Engel's Coefficient——A Case Study of Rural Areas in Hebei Province
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作者 HAO Jun1,LIU Jie2 1.Shijiazhuang Postal Vocational and Technical College,Shijiazhuang 050021,China 2.Business School,Hebei Normal University,Shijiazhuang 050024,China 《Asian Agricultural Research》 2011年第4期24-29,共6页
On the basis of introducing relevant theories of Engel's coefficient,this paper analyzes the limitation of these theories in practical application currently in China,for example,continuing to use original theory,n... On the basis of introducing relevant theories of Engel's coefficient,this paper analyzes the limitation of these theories in practical application currently in China,for example,continuing to use original theory,not in line with reality of China;comparison invalidity in length and breadth,is not conducive to relevant analysis;culling out the special factors easily causes distortion of conclusion.Taking rural areas in Hebei Province as an example,this paper analyzes the limitation of Engel's coefficient in analyzing the gap of rural economy:in terms of region horizontally,Engel's coefficient neglects the difference of consumption structure among regions,and difference of economic stages among regions;in terms of time vertically,Engel's coefficient neglects the periodic change of consumption structure and the ratio change of different families in different periods.According to the reality of China's rural areas,the correction model of Engel's coefficient is established as follows.Firstly,Engel's coefficient=Percentage of expenditure variation(food+ education+ medical service) /Percentage of total expenditure variation;Engel's coefficient=Percentage of expenditure variation(food+ education+ medical service) /Percentage of income variation.Secondly,Engel's coefficient=Percentage of expenditure variation of food/Percentage of variation of(total expenditure educational expenditure-medical expenditure.Thirdly,Engel's coefficient=Percentage of expenditure variation of food/Percentage of total expenditure variation. 展开更多
关键词 Engel’s COEFFICIENT DIFFERENCE of CONSUMPTION stru
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Process and mechanism of arable land change in Hebei Province during the past 50 years 被引量:3
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作者 XU Yue-qing (Institute of Geographical Sciences and Natural Resources Research, CAS, Beijing 100101, China College of Resource and Environment Science, Hebei Normal University, Shijiazhuang 050016, China ) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第4期47-52,共6页
Hebei Province is one of the regions with most densely population, fastest economic growth and most intensive land use in China. The contradiction of land shortage sharpened by high-speed economic development with pop... Hebei Province is one of the regions with most densely population, fastest economic growth and most intensive land use in China. The contradiction of land shortage sharpened by high-speed economic development with population growth has become a serious problem, which has restricted regional sustainable development.This paper revealed the basic process, regional differences of change and the gravity center of arable land area according to the long-series statistical data of arable land during the past 50 years. On the basis of the above mentioned, the major driving forces that influence the changes of the arable land are discussed. The research results indicate that there is a trend of obvious fluctuating decrease in arable land area during the last 50 years. The changes of arable land area undergo the process from increase to sharp decrease to gently decrease. The regional disparity of change in arable land area is very notable and the gravity center of arable land area moves to the northeast 49.22 km. Regarding the decrease in arable land, the direct driving forces include adjustments of agricultural structure and reclamation, and indirect driving forces include advance in technology, economic interest and population growth etc. 展开更多
关键词 decrease in arable land area changing process mechanism hebei province
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Analysis on Temporal and Spatial Changes and Driving Forces of Poverty-Stricken Areas in Hebei Province
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作者 Shi Xiaoli, Yuan Jinguo & Wang WeiCollege of Resources and Environmental Sciences, Hebei Normal University, Shijiazhuang 050016,China 《Chinese Journal of Population,Resources and Environment》 北大核心 2005年第2期42-48,共7页
This paper takes poverty-stricken countyas the basic unit, and selects net income per peasantto study the poverty status in Hebei Province during1986~2000.Temporal and spatial changes of poverty-stricken areas are ana... This paper takes poverty-stricken countyas the basic unit, and selects net income per peasantto study the poverty status in Hebei Province during1986~2000.Temporal and spatial changes of poverty-stricken areas are analyzed. The result shows thatpoverty-stricken areas in Hebei Province distributedconcentratedly and the areas decreased during1986~2000, the net income per peasant was on therise with an increasing speed in off-poverty countiesbeing slightly higher than that in poverty-strickencounties, but the growth rate was extremely unstable,rising slowly in off-poverty counties while droppingin poverty-stricken counties. The main driving forcesthat influenced temporal and spatial changes wereeconomic development of the whole province,ecological environment quality, infrastructureconditions and radiation of the key city. On thisbasis, some anti-poverty countermeasures suitable tolocal conditions are proposed. 展开更多
关键词 Poverty-stricken areas temporal andspatial changes hebei province driving forces
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THE MECHANICAL RELATIONSHIP TO THE FORMATION AND DISTRIBUTION OF THEBURIED HILLS AND THE DEEP-SEATED FRACTURAL ZONE IN THE DIWA-TYPE FAULTED BASIN IN CENTRAL HEBEI PROVINCE,CHINA
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作者 LIN Ge & WEI Zhouling (Chang sha Institute of Geotectonics, Acad emia Sinica, Chang sha, 410013) 《Geotectonica et Metallogenia》 1994年第Z1期27-31,共5页
The author proves the existence and movement of a deep-seated fraetural Zone located in the eenter zone of the diwa-type faulted basin in central Hebei Province. This deep-seated fraeturai zone tending in NNE directio... The author proves the existence and movement of a deep-seated fraetural Zone located in the eenter zone of the diwa-type faulted basin in central Hebei Province. This deep-seated fraeturai zone tending in NNE direction is a structural effect of the mtodle East Asin Grustobody in the Mexozoic-Cenozoic. This paper will diseuss the formation, evolution and the meehanism of the deep-seated fraetural zone, faulted basin and the buried hills as well as their relationships. The uthor expounds that the deep geological process is the major factor of the structural effect. 展开更多
关键词 deep-seated fraetural ZONE buried HILL east Asia Crustobody the BASIN in CENTRAL hebei province
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Problems and reconstruction of the development of rural preschool education in Hebei Province
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作者 Yang Huiliang Hou Jiaying 《International English Education Research》 2015年第5期90-91,共2页
as a part of the socialist education, preschool education is an opportunity for every school age children to have equal access to education. But in the current development of market economy, now rural preschool educat... as a part of the socialist education, preschool education is an opportunity for every school age children to have equal access to education. But in the current development of market economy, now rural preschool education appeared a series of problems. In combination with the basic characteristics of rural preschool education in our province, hope the popularity ofpre school education in rural and other areas to achieve the integration of urban and rural areas play a reference 展开更多
关键词 hebei province rural areas preschool education EQUALIZATION
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冀北上黄旗地区多金属矿成矿规律与矿产预测
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作者 高攀 张有军 +3 位作者 刘战鹏 王鹏飞 李继业 李松彬 《地质找矿论丛》 CAS 2024年第1期35-44,共10页
冀北上黄旗地区位于华北地台北缘中段成矿带及兴安太行南段成矿带的相交区域,是华北地区著名的(银)多金属成矿区。本文在综合分析区域成矿地质背景、成矿地质条件、地球物理、地球化学、遥感异常特征及成矿规律的基础上,认为该区具有寻... 冀北上黄旗地区位于华北地台北缘中段成矿带及兴安太行南段成矿带的相交区域,是华北地区著名的(银)多金属成矿区。本文在综合分析区域成矿地质背景、成矿地质条件、地球物理、地球化学、遥感异常特征及成矿规律的基础上,认为该区具有寻找侵入岩型和陆相火山岩型两大类多金属矿床的有利条件,划分出3条Ⅳ级成矿亚带,圈定成矿远景区10个。其中,A类4处,B类4处,C类2处;并优选出多金属矿找矿靶区7个,A类4个,B类2个,C类1个。 展开更多
关键词 多金属矿 成矿远景区 找矿靶区 上黄旗地区 冀北
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青海东部干旱区不同紫花苜蓿品种饲用品质和生产性能比较
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作者 王龙然 王伟 +3 位作者 蒲小剑 魏希杰 傅云洁 徐成体 《草地学报》 CAS CSCD 北大核心 2024年第6期1936-1943,共8页
为筛选出适宜青海省东部干旱区种植的紫花苜蓿(Medicago sativa L.),促进当地畜牧业发展,本研究对29个紫花苜蓿品种生育期、生产性能和营养品质进行对比分析,并采用灰色关联度分析法对参试品种的各项指标综合评价。结果表明:参试紫花苜... 为筛选出适宜青海省东部干旱区种植的紫花苜蓿(Medicago sativa L.),促进当地畜牧业发展,本研究对29个紫花苜蓿品种生育期、生产性能和营养品质进行对比分析,并采用灰色关联度分析法对参试品种的各项指标综合评价。结果表明:参试紫花苜蓿均可在青海省东部干旱区完成整个生育期,生育期介于172~174 d间,差异较小。29个紫花苜蓿中‘大业3号’鲜干草产量均为最高;‘西贝’株高超1.00 m,显著高于其它品种(P<0.05);‘佳能’分枝数最多超过15个;‘磐石’粗蛋白含量最高,达21.71%DM;‘MT4015’中酸性洗涤纤维含量均较低;‘MT4015’和‘磐石’相对饲喂为价值较高,显著高于其他品种(P<0.05)。利用灰色关联度综合饲用价值和生产性能进行排序,发现‘磐石’‘大业3号’‘218TR’位居前列,兼顾产量和品质,适宜在该地推广种植。 展开更多
关键词 青海省东部干旱区 紫花苜蓿 营养品质 生产性能
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海域资源资产收益管理和分配研究——以河北省为例
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作者 沈佳纹 谷青华 +4 位作者 霍永伟 田洪军 张慧 曹英志 李亚宁 《中国国土资源经济》 2024年第6期59-66,共8页
健全完善海域资源资产收益管理和分配制度是自然资源资产产权制度改革的关键环节,也是全民所有自然资源资产所有权委托代理机制试点工作的重点内容。文章系统梳理了海域资源资产收益来源、收益形式、收益征收管理和分配现状,并以河北省... 健全完善海域资源资产收益管理和分配制度是自然资源资产产权制度改革的关键环节,也是全民所有自然资源资产所有权委托代理机制试点工作的重点内容。文章系统梳理了海域资源资产收益来源、收益形式、收益征收管理和分配现状,并以河北省为例,探讨了当前海域资源资产收益管理与分配中存在的问题:①资产配置以行政手段为主,市场化水平不高;②海域使用金征收标准偏低,资产收益实现形式单一;③资产收益分配不合理,央地财政事权划分不匹配。基于此,文章提出在分级行使海域资源资产所有权模式下完善收益管理和分配制度的对策建议:①深化海域有偿使用制度改革;②完善海域资源资产收益管理路径,合理划分财权事权;③强化预算管理;④建立收益管理成效评价机制。 展开更多
关键词 海域资源资产 收益管理 收益分配 河北省
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冀东迁安地区BIF型铁矿地质特征及成因探讨
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作者 许曼 吕水 +5 位作者 韦文国 邢运涛 刘海龙 杨爱雪 李彪 安梦莹 《地质与勘探》 CAS CSCD 北大核心 2024年第5期900-918,共19页
冀东迁安地区是我国重要的BIF型铁矿集区之一。随着铁矿床开发利用程度的提高,浅部铁矿资源开发殆尽。近年来,多家地勘单位在迁安地区大中型铁矿床深部及外围进行找矿工作,在深部新发现了厚大矿体,取得了找矿突破。虽然勘查取得一定的成... 冀东迁安地区是我国重要的BIF型铁矿集区之一。随着铁矿床开发利用程度的提高,浅部铁矿资源开发殆尽。近年来,多家地勘单位在迁安地区大中型铁矿床深部及外围进行找矿工作,在深部新发现了厚大矿体,取得了找矿突破。虽然勘查取得一定的成果,但相关的铁矿床分布规律及成矿模式未进行过系统的研究,对迁安地区成矿带缺少整体认识。本文系统分析了迁安地区沉积变质型铁矿的成矿地质条件,总结了赋矿地层特征。进行了迁安地区铁矿褶皱构造五级划分,确定三级倒转向斜构造为主要控矿构造。初步厘定了断裂构造为成矿期后的脆性断裂,多对矿体产生破坏和错断;明确了迁安地区铁矿分布在迁安隆起向南西突出的“C”字形边缘弧形褶皱带中,形态受倒转向斜控制。针对迁安部分矿区发现的第二层铁矿体,进行了深、浅部矿体地质特征对比分析,认为海底热液喷气活动具有周期性,原始沉积时形成了多层铁矿层,并经受成矿期后断裂构造改造,形成北高南低的阶梯状地堑赋矿模式。依据多年的勘探成果结合本次研究工作,建立了迁安地区成矿模式,为下一步找矿工作提供了理论支撑。 展开更多
关键词 BIF铁矿 矿床分布规律 构造作用 成矿模式 迁安地区 冀东
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河北省典型铅锌矿区重金属来源解析及生态风险评价 被引量:2
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作者 刘安 于聪灵 +4 位作者 王立平 宋娟娟 孙连伟 金倩 孙孟华 《地质科技通报》 CAS CSCD 北大核心 2024年第2期307-317,共11页
为揭示河北省典型铅锌矿区重金属来源及生态风险,以河北省某铅锌矿区周边区域为研究对象,通过系统的田间采样采集了156件土壤样品,通过主成分分析(PCA)及正定矩阵因子分解(PMF)模型分析,分析了区域内重金属的来源;运用地累积指数法及潜... 为揭示河北省典型铅锌矿区重金属来源及生态风险,以河北省某铅锌矿区周边区域为研究对象,通过系统的田间采样采集了156件土壤样品,通过主成分分析(PCA)及正定矩阵因子分解(PMF)模型分析,分析了区域内重金属的来源;运用地累积指数法及潜在生态风险指数法进行了风险评价。研究结果表明,Cr,Ni,Cu,Zn,As,Cd,Pb和Hg质量分数平均值分别为53.6,25.7,62.7,692,10.6,1.75,142,0.129 mg/kg,除Cr,Ni和As外,其余5种重金属均处于不同的污染水平,平均值均超河北省土壤背景值,Hg,Cd,Zn,Pb和Cu的变异系数均大于1.75,As的变异系数大于0.5,表明这6种重金属属于高度变异。源解析显示,研究区土壤重金属的主要来源为采矿活动、自然来源、农业活动和金矿冶炼,其中,Pb,Zn和Cd主要源于采矿活动;Cr,Ni主要受自然母质的影响,属于自然来源;Cu主要受农业活动和采矿活动的双重影响;As受自然来源、采矿活动和农业活动三重控制;Hg主要源于金矿冶炼和采矿活动。PCA与PMF模型有机结合、彼此印证,增加了重金属来源解析结果的可信度。研究区存在人为因素引起的Hg和Cd污染,地累积指数和潜在生态风险指数高,生态风险总体属于极高生态风险,需要重点关注并开展治理工作。 展开更多
关键词 重金属 来源解析 统计分析 生态风险 铅锌矿区 河北省
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冀北山地桦木林土壤细菌群落特征对坡向的响应
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作者 于小萌 高青青 +3 位作者 许竹锐 马旭满 孟亚馨 徐学华 《林业与生态科学》 2024年第3期288-296,共9页
为了揭示冀北山地桦木林土壤细菌群落特征对坡向的响应规律,以冀北山地阴坡、半阴坡和半阳坡桦木林土壤为研究对象,采用高通量测序技术,分析了土壤细菌群落结构和多样性。结果表明:细菌群落组成主要包含41门、107纲,其中优势细菌门为变... 为了揭示冀北山地桦木林土壤细菌群落特征对坡向的响应规律,以冀北山地阴坡、半阴坡和半阳坡桦木林土壤为研究对象,采用高通量测序技术,分析了土壤细菌群落结构和多样性。结果表明:细菌群落组成主要包含41门、107纲,其中优势细菌门为变形菌门和酸杆菌门;土壤细菌群落α多样性指数在坡向间存在显著差异,阴坡>半阴坡>半阳坡;土壤含水量、容重、硝态氮和氨态氮均影响细菌微生物群落的结构组成,其中,土壤含水量与多种细菌门存在显著相关性,且与细菌α多样性存在极显著的正相关性。综上所述,不同坡向桦木林土壤细菌群落结构和多样性呈现出一定的变化规律,坡向和土层深度变化引起的土壤含水量变化是该地区桦木林土壤细菌群落结构和多样性差异的主要因素。 展开更多
关键词 桦木林 坡向 土壤细菌 群落多样性 冀北山地
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基于域—生物群系—功能群分类的生态系统类型识别及时空格局变化分析——以河北省太行山区为例
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作者 毕善婷 陈影 +3 位作者 李泽 屈爽 赵文超 梁阅兵 《水土保持通报》 CSCD 北大核心 2024年第2期236-244,257,共10页
[目的]科学识别河北省太行山区生态系统类型,是理解河北省太行山区生态系统时空分布格局和支撑生态系统分类管理的基础。[方法]基于域—生物群系—功能群(RBE)的分类原理,构建了包括3个1级,8个2级和24个3级类的生态系统分类体系,并集成... [目的]科学识别河北省太行山区生态系统类型,是理解河北省太行山区生态系统时空分布格局和支撑生态系统分类管理的基础。[方法]基于域—生物群系—功能群(RBE)的分类原理,构建了包括3个1级,8个2级和24个3级类的生态系统分类体系,并集成多源数据,开展了2000和2020年的河北省太行山区生态系统的分类制图。基于RUSLE模型、InVEST模型和热点分析等方法,分析生态系统服务的时空格局演变。[结果]①河北省太行山区20 a间建设用地生态系统增加最多,主要来自农田生态系统。农田生态系统缩减了61105.95 hm^(2),以雨养农田为主。受人类活动的影响,河流和人工湿地面积分别增加了5584.32和2535.66 hm^(2),而林地和草地生态系统减幅分别为0.96%和8.18%。未利用地生态系统受研究区生态保护措施影响减少5800.68 hm^(2)。②生态系统服务值受生态系统类型分布影响总体呈现西高东低的分布格局,除粮食供给服务为西低东高,主要是由于农田主要分布在东部地区。③冷热点区域空间分布整体上具有重叠性,但仍有差异。[结论]提出的分类体系具有可行性,分类精度达到80%以上,符合研究区的生态系统类型变化趋势,可为识别山区生态系统分类和生态系统保护修复政策提供科学支撑,进而促进山区生态发展目标和可持续发展的实现。 展开更多
关键词 生态系统分类 生态系统服务 时空分布格局 河北省太行山区
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冀东沿海沙滩微塑料污染特征及影响因素研究
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作者 张蒨 张雄帅 宋泽峰 《河北地质大学学报》 2024年第5期92-96,123,共6页
沿海海滩是微塑料聚集和暴露的重要区域,并广泛存在于沙质海滩。以河北省秦皇岛浅水湾滨海浴场、昌黎黄金海岸滨海浴场、唐山祥云湾滨海浴场为例,探究了沙滩微塑料的污染特征及影响因素。通过采集12个沙滩样品进行分析,显示浅水湾、黄... 沿海海滩是微塑料聚集和暴露的重要区域,并广泛存在于沙质海滩。以河北省秦皇岛浅水湾滨海浴场、昌黎黄金海岸滨海浴场、唐山祥云湾滨海浴场为例,探究了沙滩微塑料的污染特征及影响因素。通过采集12个沙滩样品进行分析,显示浅水湾、黄金海岸、祥云湾沙滩微塑料丰度处于较低水平,黑色为3个沙滩微塑料常见颜色,纤维状为主要微塑料形状,粒径主要分布在500~2 000μm之间,聚合物成分均以人造丝为主要类型,浅水湾沙滩中也存在一定量的氯化聚乙烯。从统计结果看出,微塑料的丰度主要受游客数量、渔业活动和潮汐动力等人为和自然的多种因素影响。研究成果有助于了解沙滩沉积物中微塑料的污染特征及来源,为微塑料管控、减排及防治决策提供科学依据。 展开更多
关键词 冀东沿海 沙滩微塑料 污染特征 影响因素
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东昆仑清水河东沟钼矿床成矿模式探讨
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作者 马忠元 张勇 +1 位作者 李军 马强 《地质找矿论丛》 CAS 2024年第3期293-300,共8页
本文在总结东昆仑清水河东沟钼矿床成矿地质背景和矿床特征的基础上,通过分析矿石的流体包裹体特征,探讨了矿床成因并建立了成矿模式。研究表明,清水河东沟钼矿床是与浅成超浅成斑岩侵入活动有关的斑岩型钼矿床,成矿岩体为二长花岗斑岩... 本文在总结东昆仑清水河东沟钼矿床成矿地质背景和矿床特征的基础上,通过分析矿石的流体包裹体特征,探讨了矿床成因并建立了成矿模式。研究表明,清水河东沟钼矿床是与浅成超浅成斑岩侵入活动有关的斑岩型钼矿床,成矿岩体为二长花岗斑岩,在斑岩及蚀变围岩中发育呈层状、似层状、透镜状钼矿体;辉钼矿多以鳞片集合体状、星点状分布于石英脉体中及岩石裂隙面上,少量以细脉浸染状分布于蚀变岩石中;矿石流体包裹体具有高—低温、低盐度、低密度的特点。清水河东沟钼矿床形成于晚三叠世后碰撞伸展环境,成矿物质来源主要为斑岩岩浆。该研究结果可为进一步开展区域成矿规律研究和找矿勘查工作提供参考。 展开更多
关键词 清水河东沟钼矿床 斑岩型钼矿 成矿模式 东昆仑 青海省
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河北省张北地区土壤和莜麦重金属含量及健康风险研究
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作者 鲁倩 王雪飞 +4 位作者 车健 马程 余明 边朋沙 张硕 《安徽农业科学》 CAS 2024年第6期81-85,共5页
为探讨河北省张北地区土壤和莜麦中重金属元素含量及健康风险,选择17个适宜采样点进行表层土壤和莜麦籽实样品的采集,通过单因子污染指数法、综合污染指数法和富集系数分别对土壤质量和重金属元素从土壤向莜麦迁移能力进行研究。结果表... 为探讨河北省张北地区土壤和莜麦中重金属元素含量及健康风险,选择17个适宜采样点进行表层土壤和莜麦籽实样品的采集,通过单因子污染指数法、综合污染指数法和富集系数分别对土壤质量和重金属元素从土壤向莜麦迁移能力进行研究。结果表明:研究区土壤和莜麦中重金属含量远低于国家标准,品质安全健康;区内重金属元素在土壤-莜麦系统中富集能力为Zn>Cu>Ni>Cd>As>Pb>Cr=Hg, Ni、Cu和Zn的富集系数远高于Cr、As、Cd、Hg、Pb, Cd迁移能力很弱,As、Pb几乎不发生迁移,Cr、Hg不发生迁移。 展开更多
关键词 重金属元素 含量测定 土壤 莜麦 健康风险 河北省张北地区
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冀鲁部分地区鸡源空肠弯曲菌耐药性与遗传进化特征研究
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作者 李晶晶 郑培培 +6 位作者 罗青平 张腾飞 闫振达 殷梦玉 刘建钗 刘彦威 李朋辉 《黑龙江畜牧兽医》 CAS 北大核心 2024年第22期68-74,133,共8页
为了解冀鲁部分地区鸡群空肠弯曲菌的感染情况、耐药性与遗传进化特征,试验于2020年11月份—2021年12月份采集邯郸市、邢台市、石家庄市、聊城市部分养鸡场泄殖腔拭子369份,对空肠弯曲菌进行分离培养与纯化、PCR鉴定;采用Kirby-Bauer(K... 为了解冀鲁部分地区鸡群空肠弯曲菌的感染情况、耐药性与遗传进化特征,试验于2020年11月份—2021年12月份采集邯郸市、邢台市、石家庄市、聊城市部分养鸡场泄殖腔拭子369份,对空肠弯曲菌进行分离培养与纯化、PCR鉴定;采用Kirby-Bauer(K-B)纸片扩散法对分离到的空肠弯曲菌进行耐药性分析;选取有代表性的分离菌株,通过扩增7个空肠弯曲菌管家基因进行多位点序列分型(multilocus sequence typing,MLST)分析和遗传进化分析。结果表明:采集的369份鸡泄殖腔拭子样品中有88份为空肠弯曲菌阳性,阳性率为23.85%;共分离出16株空肠弯曲菌,分离率为4.34%。16株分离菌株对链霉素、红霉素和阿奇霉素的耐药率最高,均为93.75%;对左氧氟沙星、磺胺甲口恶唑、林可霉素、多黏菌素、头孢噻呋、大观霉素、头孢噻肟和新霉素的耐药率较高,为50.00%~87.50%;对恩诺沙星的耐药率为43.75%;对阿莫西林的耐药率为37.50%;对氧氟沙星、庆大霉素和氨苄西林的耐药率均为31.25%;对青霉素和氟苯尼考的耐药率均为25.00%;对多西环素和万古霉素的耐药率最低,均为18.75%。选取的10株有代表性的分离菌株[邯郸市3株(HeBHD-1、HeBHD-2、HeBHD-3)、邢台市2株(HeBXT-1、HeBXT-2)、石家庄市2株(HeBSJZ-1、HeBSJZ-2)、聊城市3株(SDLC-1、SDLC-2、SDLC-3)]共属于8个序列型别(sequence type,ST),其中HeBHD-3为新的ST(ST12017),HeBHD-2和SDLC-3为ST6077,SDLC-1和SDLC-2为ST4259,HeBHD-1、HeBSJZ-1、HeBXT-1、HeBXT-2和HeBSJZ-2分别为ST2328、ST1213、ST1723、ST11076和ST11851。仅4株被归类为克隆群CC,其中HeBXT-1、SDLC-1和SDLC-2属于克隆群CC-354,HeBSJZ-1属于克隆群CC-460,另外6株的ST没有被归类为任何克隆群。HeBXT-1、SDLC-1、SDLC-2、HeBSJZ-1、SDLC-3和HeBHD-3(新的ST)分离株与上海人源参考株SHI IC140的亲缘关系最近,HeBHD-1和HeBSJZ-2分离株与四川鹌鹑源参考株V20的亲缘关系最近,而HeBHD-2和HeBXT-2分离株与河南人源参考株HN-CJD07042的亲缘关系最近。说明冀鲁部分地区鸡群存在空肠弯曲菌感染的情况,分离菌株耐药性较为严重,且遗传进化特征呈现多样性,因此应加强对该地区鸡群空肠弯曲菌的动态监测。 展开更多
关键词 冀鲁部分地区 空肠弯曲菌 耐药特征 多位点序列分型 遗传进化分析
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