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黄河三角洲垦利县夏季土壤水盐空间变异及土壤盐分微域特征 被引量:50
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作者 王卓然 赵庚星 +4 位作者 高明秀 常春艳 姜曙千 贾吉超 李晋 《生态学报》 CAS CSCD 北大核心 2016年第4期1040-1049,共10页
黄河三角洲作为我国重要的后备土地资源区,土壤盐渍化问题突出,切实掌握季节性土壤水盐状况及其微域特征是该区土壤盐渍化防控和土地资源高效利用的重要基础。选择黄河三角洲垦利县,通过野外调查实测与室内化验分析获取土壤水盐含量数据... 黄河三角洲作为我国重要的后备土地资源区,土壤盐渍化问题突出,切实掌握季节性土壤水盐状况及其微域特征是该区土壤盐渍化防控和土地资源高效利用的重要基础。选择黄河三角洲垦利县,通过野外调查实测与室内化验分析获取土壤水盐含量数据,利用统计分析、GIS空间插值、实地观测与数据分析对比等方法,分析了研究区夏季土壤水盐状况及其微域变异规律。结果显示:研究区夏季土壤水盐含量总体较高,含盐量以中度盐渍化为主,随着土层深度的增加含盐量呈上升趋势,且各层土壤含盐量呈显著正相关性;含盐量较高的地区主要分布在该区东北部和中东部,含盐量较低的地区主要分布在西南部和中部;土壤含盐量从大到小的植被类型依次为光板地→碱蓬→高粱→芦苇→茅草→水稻→棉花→玉米;土壤盐分微域变化特征明显,含盐量受距路边远近、不同耕作措施、地形部位、植被群落等因素影响较大,表现出微域规律性和复杂性。该研究基本摸清了研究区夏季时相的土壤水盐状况及其微域特征,为黄河三角洲农作物栽培管理及土壤资源可持续利用提供了科学依据。 展开更多
关键词 垦利县 夏季 土壤含盐量 土壤含水量 空间变异 微域特征
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生物质炭输入对土壤微域特征及土壤腐殖质的作用效应研究 被引量:42
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作者 花莉 金素素 洛晶晶 《生态环境学报》 CSCD 北大核心 2012年第11期1795-1799,共5页
农田土壤有机碳矿化释放CO2是农业温室气体排放的重要途径,生物质炭因其特殊的性质对增强土壤碳截获能力及减少土壤CO2气体排放可能具有重要作用。在2种不同肥力的自然土壤中加入不同含量的生物质炭,通过对比输入生物质炭的土壤和对照... 农田土壤有机碳矿化释放CO2是农业温室气体排放的重要途径,生物质炭因其特殊的性质对增强土壤碳截获能力及减少土壤CO2气体排放可能具有重要作用。在2种不同肥力的自然土壤中加入不同含量的生物质炭,通过对比输入生物质炭的土壤和对照土壤腐殖质含量和土壤微粒在扫面电镜及红外光谱观测下微域特征的变化,探讨生物质炭对土壤碳固定潜力的影响。结果表明,生物质炭的输入可以促进土壤腐殖质的形成,与对照相比,腐植酸、富里酸和胡敏酸含量均有所增加,有利于土壤有机碳库的稳定;此外生物质炭的添加,使土壤微域环境中粒间孔隙增多,比表面积增大,有助于促进土壤有机质的积累;提高了土壤养分,增加结合矿物质所需的元素;促进了粘粒、有机质等矿物质的形成,从而减缓了有机质的分解速率。此外,生物质炭的添加促进了碳水化合物、酯族、芳烃等有机大分子的形成,难以被土壤微生物利用。总之,生物质炭的施用对土壤碳固定潜力存在多方面的重要影响,进而对土壤有机碳截获及CO2释放产生影响。 展开更多
关键词 生物质炭 CO2 腐殖质 土壤碳截留 土壤微域特征
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黄连木五倍子产结的微域生境特征的研究 被引量:2
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作者 舒常庆 涂炳坤 《华中农业大学学报》 CAS CSCD 北大核心 1998年第6期574-577,共4页
关键词 黄连木 五倍子 生境特征
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Zonal Distribution of the Erosion-Landslide and Soil Micromorphological Features in Purple Hilly Region 被引量:6
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作者 HEYurong LIAOChaolin XUPei ZHANGBaohua 《Journal of Mountain Science》 SCIE CSCD 2005年第1期42-49,共8页
In the purple hilly region, erosions and landslides are all serious, and it is of great scientific value and practical significance to study their formation mechanism and distribution features there. In this paper, so... In the purple hilly region, erosions and landslides are all serious, and it is of great scientific value and practical significance to study their formation mechanism and distribution features there. In this paper, soil micromorphological methods and techniques were used to study the erosion zonal distribution in the region. The results indicated: (1) According to erosion process, the spacial distribution zones of the erosions and landslides in the purple hilly region with different solums were divided into scouring erosion zone, transport-diffusion zone, rocks and soil turbulence zone and sediment-bury zone; (2) The soil micromorphologic taxonomic feature identifying different erosion-landslide zone were found by studying the soil micromorphology of erosive zone in purple hilly region; (3) As for the erosion–landslide formation in the region, besides the external factors, the internal factors were found more important and favorable for landslide formation through the studies on the micormorphological features of slide soil. 展开更多
关键词 Purple hilly region erosion-landslide zonal distribution soil micromorphology
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Scaling Analysis and its Applications of Electrostatic Micromotors
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作者 王欣利 程树康 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第2期177-180,共4页
An electrostatic micromotor is compared with a conventional electromagnetic mieromotor, and the scaling effect of driving forces is analysed according to their different operation principles. Characteristic dimension ... An electrostatic micromotor is compared with a conventional electromagnetic mieromotor, and the scaling effect of driving forces is analysed according to their different operation principles. Characteristic dimension L represents the linear scale of micromotors. Electromagnetic driving force is proportional to high-order power of characteristic dimension L whereas electrostatic driving force is not. So, in micro domain, the effect of electrostatic force is larger than that of electromagnetic force, which makes electrostatic micromotor more competitive against electromagnetic alternative in MEMS. In assessing the performance of a micromotor, the power per unit volume and efficiency are the two most important criteria. Hence, the two kinds of micromotors are further compared from these two aspects. The results indicate that electrostatic a micromotor has higher power per unit volume and efficiency, moreover, its structure is simple, it can be made sufficiently small. For those advantages of electrostatic micromotors, they can be used in optical devices, aerospace equipment and medical instruments. 展开更多
关键词 MEMS scaling effect characteristic dimension micro domain
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