To investigate the effects of long-term fertilization systems on soil microbial community structure,labile organic carbon and nitrogen and enzyme activity in yellow sand paddy field and upland,a field experiment was c...To investigate the effects of long-term fertilization systems on soil microbial community structure,labile organic carbon and nitrogen and enzyme activity in yellow sand paddy field and upland,a field experiment was conducted at the experimental station of Dongyang Institute of Maize Research in Zhejiang Province,China in 2009.The experiment consisted of six treatments with three replicates,and they were arranged in a completely randomized design,including no fertilization in paddy field (PCK),conventional fertilization in paddy field (PCF),formulated fertilization by soil testing in paddy field (PSTF),formulated fertilization by soil testing with organic manure in paddy field (PSTF+OF),conventional fertilization on upland (DCF),and formulated fertilization by soil testing with organic manure on upland (DSTF+OF).Soil nutrients,enzyme activity,microbial biomass and community structure were determined in 2015.The results showed that compared with no fertilization in paddy field (PCK),fertilization increased soil phosphorus and potassium content,and decreased pH value.No fertilization in paddy field (PCK) had no significant effect on soil culturable microorganisms in paddy field and upland,but formulated fertilization by soil testing with organic manure on upland (DSTF+OF) significantly increased the number of fungi.Formula fertilization by soil testing with organic manure (PSTF+OF) also significantly increased soil microbial biomass carbon and nitrogen in paddy field and upland.Moreover,fertilization had no significant effect on soil cellulase activity,but formula fertilization by soil testing with organic manure (PSTF+OF) significantly increased soil dehydrogenase and catalase activity.Therefore,long-term application of chemical fertilizer with organic fertilizer can effectively improve soil fertility.展开更多
现代汽车直喷发动机应用越来越广泛,直喷技术在提升发动机性能的同时,也使发动机机油稀释问题越来越突出。机油稀释需要进行控制,但是很难完全避免,因此测量机油稀释的水平就显得尤其重要。机油稀释测试技术直接影响发动机试验开发效率...现代汽车直喷发动机应用越来越广泛,直喷技术在提升发动机性能的同时,也使发动机机油稀释问题越来越突出。机油稀释需要进行控制,但是很难完全避免,因此测量机油稀释的水平就显得尤其重要。机油稀释测试技术直接影响发动机试验开发效率,快速有效的方法和合理的试验验证项目能够确保产品开发满足目标要求。目前直喷发动机开发过程中,一般主要采用机油称重法,元素示踪法、空燃比理论计算法进行测试研究,再结合机油化学成分分析,得出机油稀释率水平。机油稀释试验验证项目涵盖从发动机技术配置到ECU(Engine Control Unit)软件标定参数到可靠耐久性等各个方面。详细研究了发动机行业对于机油稀释问题试验测试技术的相关进展。展开更多
基金Supported by National Modern Agricultural Industrial Technology System(CARS-02-69)Major Agriculture Science Foundation of Upland Grain Crops Breeding of Zhejiang Province(2016C02050-9-1)Project for Training of Youth Talents of Zhejiang Academy of Agricultural Sciences(2015)
文摘To investigate the effects of long-term fertilization systems on soil microbial community structure,labile organic carbon and nitrogen and enzyme activity in yellow sand paddy field and upland,a field experiment was conducted at the experimental station of Dongyang Institute of Maize Research in Zhejiang Province,China in 2009.The experiment consisted of six treatments with three replicates,and they were arranged in a completely randomized design,including no fertilization in paddy field (PCK),conventional fertilization in paddy field (PCF),formulated fertilization by soil testing in paddy field (PSTF),formulated fertilization by soil testing with organic manure in paddy field (PSTF+OF),conventional fertilization on upland (DCF),and formulated fertilization by soil testing with organic manure on upland (DSTF+OF).Soil nutrients,enzyme activity,microbial biomass and community structure were determined in 2015.The results showed that compared with no fertilization in paddy field (PCK),fertilization increased soil phosphorus and potassium content,and decreased pH value.No fertilization in paddy field (PCK) had no significant effect on soil culturable microorganisms in paddy field and upland,but formulated fertilization by soil testing with organic manure on upland (DSTF+OF) significantly increased the number of fungi.Formula fertilization by soil testing with organic manure (PSTF+OF) also significantly increased soil microbial biomass carbon and nitrogen in paddy field and upland.Moreover,fertilization had no significant effect on soil cellulase activity,but formula fertilization by soil testing with organic manure (PSTF+OF) significantly increased soil dehydrogenase and catalase activity.Therefore,long-term application of chemical fertilizer with organic fertilizer can effectively improve soil fertility.
文摘现代汽车直喷发动机应用越来越广泛,直喷技术在提升发动机性能的同时,也使发动机机油稀释问题越来越突出。机油稀释需要进行控制,但是很难完全避免,因此测量机油稀释的水平就显得尤其重要。机油稀释测试技术直接影响发动机试验开发效率,快速有效的方法和合理的试验验证项目能够确保产品开发满足目标要求。目前直喷发动机开发过程中,一般主要采用机油称重法,元素示踪法、空燃比理论计算法进行测试研究,再结合机油化学成分分析,得出机油稀释率水平。机油稀释试验验证项目涵盖从发动机技术配置到ECU(Engine Control Unit)软件标定参数到可靠耐久性等各个方面。详细研究了发动机行业对于机油稀释问题试验测试技术的相关进展。
