为揭示金沙江干热河谷冲沟集水区土壤优先流特征,以金沙江元谋干热河谷地区不同发育程度冲沟(活跃期、稳定期)集水区为研究对象,采用野外染色示踪和统计分析相结合的方法,通过图像处理技术,从野外染色图像中整合出相关5个优先流特征指标...为揭示金沙江干热河谷冲沟集水区土壤优先流特征,以金沙江元谋干热河谷地区不同发育程度冲沟(活跃期、稳定期)集水区为研究对象,采用野外染色示踪和统计分析相结合的方法,通过图像处理技术,从野外染色图像中整合出相关5个优先流特征指标,并结合根系特征,对比分析土壤优先流差异规律。结果表明:(1)稳定期冲沟集水区在0—15 cm土层深度范围出现大面积的团块状染色,随后呈小枝状分布,染色区分布相对更加集中,活跃期染色呈整体状—团块状—枝状分布,表明活跃期冲沟集水区染色形态特征更加分化。(2)活跃期冲沟集水区的平均基质流深度、平均染色面积比、平均土壤染色斑块形状系数和优先流平均长度指数(20.53 cm, 54.25%,24.94,592.46%)分别是稳定期冲沟集水区的1.79,1.62,2.20,1.16倍,表现为活跃期冲沟系统集水区优先流发生时间相对滞后,优先流发育程度更大,优先流空间异质性相对较强。(3)随土层深度增加,根重密度和根长密度均呈减小趋势,且二者与染色面积比均呈显著正相关关系(p<0.05)。活跃期冲沟集水区各土层根重密度和根长密度均大于稳定期冲沟集水区。研究结果为揭示金沙江干热河谷冲沟集水区土壤优先流特征提供理论依据,同时为该地区生态恢复与水土保持工作提供参考和借鉴。展开更多
【目的】探究土壤优先流的形成机理,揭示林地土壤水分运移规律,加深对森林调节水文、涵养水源机理的认识,为滇中林区水源涵养、植被生态建设提供理论依据。【方法】以滇中磨盘山云南松林、华山松林、滇油杉林、高山栎林4种林分类型为研...【目的】探究土壤优先流的形成机理,揭示林地土壤水分运移规律,加深对森林调节水文、涵养水源机理的认识,为滇中林区水源涵养、植被生态建设提供理论依据。【方法】以滇中磨盘山云南松林、华山松林、滇油杉林、高山栎林4种林分类型为研究对象,利用染色示踪法和Photoshop CS 5、Image Pro Plus 6.0图像处理软件获取优先流染色区域总面积和染色面积比,分析不同林分类型的土壤优先流特征及优先流染色面积比随土层深度的变化;同时测定各林分类型土壤的理化性质,采用相关分析、主成分分析和通径分析方法,研究影响4种林分土壤优先流特征的土壤因子。【结果】4种林分表层土壤水分运动以基质流为主,染色面积比随土层深度的增加逐渐减小,优先流现象明显,优先流发育程度表现为华山松林>云南松林>滇油杉林>高山栎林。4种林分不同土层深度的土壤理化性质存在显著差异(P<0.05),华山松林地的土壤疏松程度、持水特性、土壤肥力特性均表现最优。4种林分土壤容重均与染色面积比呈极显著负相关(P<0.01),pH、全钾含量与染色面积比呈负相关;除土壤容重、pH、全钾含量外,饱和持水量、毛管持水量、毛管孔隙度、有机质含量等土壤因子均与染色面积比呈正相关关系。主成分分析和通径分析结果表明,优先流的形成是不同土壤因子直接作用和间接作用的结果,其中土壤容重是引起染色面积比变化的决定性因子,全氮含量对优先流的形成具有限制性作用。【结论】土壤疏松程度、持水特性、土壤肥力特性等共同作用影响优先流的形成与发生,土壤理化性质是土壤优先流形成的重要驱动因素。展开更多
Recently, some new characteristics of complex networks attract the attentions of scientist, in different fields, and lead to many kinds of emerging research directions. So far, most of the researcl work has been limit...Recently, some new characteristics of complex networks attract the attentions of scientist, in different fields, and lead to many kinds of emerging research directions. So far, most of the researcl work has been limited in discovery of complex network characteristics by structure analysis in large-scale software systems. This paper presents the theoretical basis, design method, algorithms and experiment results of the research. It firstly emphasizes the significance of design method of evolution growth for network topology of Object Oriented (OO) software systems, and argues that the selection and modulation of network models with various topology characteristics will bring un-ignorable effect on the process, of design and implementation of OO software systems. Then we analyze the similar discipline of "negation of negation and compromise" between the evolution of network models with different topology characteristics and the development of software modelling methods. According to the analysis of the growth features of software patterns, we propose an object-oriented software network evolution growth method and its algorithms in succession. In addition, we also propose the parameter systems for OO software system metrics based on complex network theory. Based on these parameter systems, it can analyze the features of various nodes, links and local-world, modulate the network topology and guide the software metrics. All these can be helpful to the detailed design, implementation and performance analysis. Finally, we focus on the application of the evolution algorithms and demonstrate it by a case study. Comparing the results from our early experiments with methodologies in empirical software engineering, we believe that the proposed software engineering design method is a computational software engineering approach based on complex network theory. We argue that this method should be greatly beneficial for the design, implementation, modulation and metrics of functionality, structure and performance in large-scale OO software complex system.展开更多
文摘为揭示金沙江干热河谷冲沟集水区土壤优先流特征,以金沙江元谋干热河谷地区不同发育程度冲沟(活跃期、稳定期)集水区为研究对象,采用野外染色示踪和统计分析相结合的方法,通过图像处理技术,从野外染色图像中整合出相关5个优先流特征指标,并结合根系特征,对比分析土壤优先流差异规律。结果表明:(1)稳定期冲沟集水区在0—15 cm土层深度范围出现大面积的团块状染色,随后呈小枝状分布,染色区分布相对更加集中,活跃期染色呈整体状—团块状—枝状分布,表明活跃期冲沟集水区染色形态特征更加分化。(2)活跃期冲沟集水区的平均基质流深度、平均染色面积比、平均土壤染色斑块形状系数和优先流平均长度指数(20.53 cm, 54.25%,24.94,592.46%)分别是稳定期冲沟集水区的1.79,1.62,2.20,1.16倍,表现为活跃期冲沟系统集水区优先流发生时间相对滞后,优先流发育程度更大,优先流空间异质性相对较强。(3)随土层深度增加,根重密度和根长密度均呈减小趋势,且二者与染色面积比均呈显著正相关关系(p<0.05)。活跃期冲沟集水区各土层根重密度和根长密度均大于稳定期冲沟集水区。研究结果为揭示金沙江干热河谷冲沟集水区土壤优先流特征提供理论依据,同时为该地区生态恢复与水土保持工作提供参考和借鉴。
文摘【目的】探究土壤优先流的形成机理,揭示林地土壤水分运移规律,加深对森林调节水文、涵养水源机理的认识,为滇中林区水源涵养、植被生态建设提供理论依据。【方法】以滇中磨盘山云南松林、华山松林、滇油杉林、高山栎林4种林分类型为研究对象,利用染色示踪法和Photoshop CS 5、Image Pro Plus 6.0图像处理软件获取优先流染色区域总面积和染色面积比,分析不同林分类型的土壤优先流特征及优先流染色面积比随土层深度的变化;同时测定各林分类型土壤的理化性质,采用相关分析、主成分分析和通径分析方法,研究影响4种林分土壤优先流特征的土壤因子。【结果】4种林分表层土壤水分运动以基质流为主,染色面积比随土层深度的增加逐渐减小,优先流现象明显,优先流发育程度表现为华山松林>云南松林>滇油杉林>高山栎林。4种林分不同土层深度的土壤理化性质存在显著差异(P<0.05),华山松林地的土壤疏松程度、持水特性、土壤肥力特性均表现最优。4种林分土壤容重均与染色面积比呈极显著负相关(P<0.01),pH、全钾含量与染色面积比呈负相关;除土壤容重、pH、全钾含量外,饱和持水量、毛管持水量、毛管孔隙度、有机质含量等土壤因子均与染色面积比呈正相关关系。主成分分析和通径分析结果表明,优先流的形成是不同土壤因子直接作用和间接作用的结果,其中土壤容重是引起染色面积比变化的决定性因子,全氮含量对优先流的形成具有限制性作用。【结论】土壤疏松程度、持水特性、土壤肥力特性等共同作用影响优先流的形成与发生,土壤理化性质是土壤优先流形成的重要驱动因素。
基金Supported by the National Natural Science Foundation of China under Grant No.60373086IS0/IEC SC32 Standardization Project No.1.32.22.01.03.00+3 种基金"Tenth Five-Year Plan"National Key Project of Science and Technology under Grant No.2002BA906A21Hubei Province Key Project under Grant No.2004AA103A02Wuhan City Key Project under Grant No.200210020430pen Foundation of SKLSE under Grant No.SKLSE05-19.
文摘Recently, some new characteristics of complex networks attract the attentions of scientist, in different fields, and lead to many kinds of emerging research directions. So far, most of the researcl work has been limited in discovery of complex network characteristics by structure analysis in large-scale software systems. This paper presents the theoretical basis, design method, algorithms and experiment results of the research. It firstly emphasizes the significance of design method of evolution growth for network topology of Object Oriented (OO) software systems, and argues that the selection and modulation of network models with various topology characteristics will bring un-ignorable effect on the process, of design and implementation of OO software systems. Then we analyze the similar discipline of "negation of negation and compromise" between the evolution of network models with different topology characteristics and the development of software modelling methods. According to the analysis of the growth features of software patterns, we propose an object-oriented software network evolution growth method and its algorithms in succession. In addition, we also propose the parameter systems for OO software system metrics based on complex network theory. Based on these parameter systems, it can analyze the features of various nodes, links and local-world, modulate the network topology and guide the software metrics. All these can be helpful to the detailed design, implementation and performance analysis. Finally, we focus on the application of the evolution algorithms and demonstrate it by a case study. Comparing the results from our early experiments with methodologies in empirical software engineering, we believe that the proposed software engineering design method is a computational software engineering approach based on complex network theory. We argue that this method should be greatly beneficial for the design, implementation, modulation and metrics of functionality, structure and performance in large-scale OO software complex system.