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黑土区坡耕地施加生物炭对土壤结构与大豆产量的影响 被引量:22
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作者 魏永霞 石国新 +2 位作者 冯超 吴昱 刘慧 《农业机械学报》 EI CAS CSCD 北大核心 2019年第8期309-320,共12页
为探明黑土区施加生物炭对土壤结构、土壤肥力和作物产量及其可持续性的影响,以东北黑土区3°坡耕地田间径流小区为研究对象,进行了为期4年的观测。2015年按照生物炭的施加量共设置C0(0 t/hm^2)、C25(25 t/hm^2)、C50(50 t/hm^2)、C... 为探明黑土区施加生物炭对土壤结构、土壤肥力和作物产量及其可持续性的影响,以东北黑土区3°坡耕地田间径流小区为研究对象,进行了为期4年的观测。2015年按照生物炭的施加量共设置C0(0 t/hm^2)、C25(25 t/hm^2)、C50(50 t/hm^2)、C75(75 t/hm^2)、C100(100 t/hm^2)5个处理,2016—2018年分别连续施加等量的生物炭。结果表明:连续4年随施炭量的增加土壤容重呈逐渐降低趋势、孔隙度呈逐渐升高趋势,且施用年限越长,作用越明显;连续4年广义土壤结构系数(GSSI)随施炭量的增加呈先增大后减小的变化趋势,土壤三相结构距离指数(STPSD)呈先减小后增大的变化趋势,均在第2年C50处理取得最大(小)值(98.31、4.87),同时土壤三相比最接近理想状态;连续4年大于0.25 mm的土壤团聚体含量(R0.25)、平均质量直径(MWD)、几何平均直径(GMD)随施炭量的增加均呈先增大后减小的变化趋势,均在第2年C50处理取得最大值;连续4年土壤速效钾、有机质含量随施炭量的增加逐渐升高,土壤碱解氮和有效磷含量先增加后减小,各年份土壤碱解氮和有效磷含量提高最多的分别为C50(46.1%、76.6%)、C50(46.4%、85.4%)、C25(33%、100.7%)、C25(23.9%、103.2%);连续4年施加生物炭均可提高大豆产量、单株荚数、单株粒数和百粒质量,在第2年C50处理增产最大,增产率为33.3%,同时产量可持续性最强,产量可持续性特征指数(SYI)为0.871。 展开更多
关键词 生物炭 广义结构系数 三相结构距离指数 平均质量直径 几何平均直径 产量可持续性指数
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Generalized Dirac Equation with Vector Structural Coefficient and Its Generalized Solutions in Biquaternions Algebra
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作者 L.A. Alexeyeva 《Journal of Mathematics and System Science》 2015年第8期309-314,共6页
On the base of differential biquatemions algebra and theories of generalized functions the biquaternionic wave equation of general type is considered under vector representation of its structural coefficient. Its gene... On the base of differential biquatemions algebra and theories of generalized functions the biquaternionic wave equation of general type is considered under vector representation of its structural coefficient. Its generalized decisions in the space of tempered generalized functions are constructed. The elementary twistors and twistor fields are built and their properties are investigated. Introduction. The proposed by V.P. Hamilton quatemions algebra [1] and its complex extension - biquaternions algebra are very convenient mathematical tool for the description of many physical processes. At presence these algebras have been actively used in in the work of various authors to solve a number of problems in electrodynamics, quantum mechanics, solid mechanics and field theory. The properties of these algebras are actively studied in the framework of the theory of Clifford algebras. In the papers [2, 3] the differential algebra of biquatemions has been elaborated for construction of generalized solutions of the biquaternionic wave (biwave) equations. The particular types of biwave equations were considered, which are equivalent to the systems of Maxwell and Dirac equations and their generalizations, their biquaternionic decisions also were constructed. Here the biwave equation is considered with vector structural coefficient which is biquaternionic generalization of Dirac equations. Their generalized solutions in the space of tempered distributions are defined and their properties are researched. 展开更多
关键词 Biquaternionic wave equation Dirac equation generalized solution elementary twistor
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