A field experiment was conducted at the Shenyang Experimental Station ofEcology, Chinese Academy of Sciences, to study the effects of soil management practices on water useand rice (Oryza sativa L.) yield in an aquic ...A field experiment was conducted at the Shenyang Experimental Station ofEcology, Chinese Academy of Sciences, to study the effects of soil management practices on water useand rice (Oryza sativa L.) yield in an aquic brown soil during 2001 and 2002. A completely randomexperimental design with three replications was employed, having four soil management practices astreatments, namely: an undisturbed plow layer (CK), a thin plastic film (TN), a thick plastic film(TI) and subsoil compacting (CP). Results indicated no significant differences among all treatmentsfor rice biomass and grain yields. Also, water consumption was about the same for treatments TN andCK, however the treatments TI and CP were much lower with more than 45% and 40% of the irrigationwater in the treatments TI and CP, respectively, saved each year compared to CK. Therefore, wateruse efficiency was higher in the treatments TI and CP. These results will provide a scientific basisfor the water-saving rice cultivation.展开更多
Circulating soaked sandstone and mudstone samples sonic parameters were tested and analyzed, using RSM-SY5 sonic instrument, the variation between soaked times and the velocity of longitudinal wave and shear wave was ...Circulating soaked sandstone and mudstone samples sonic parameters were tested and analyzed, using RSM-SY5 sonic instrument, the variation between soaked times and the velocity of longitudinal wave and shear wave was studied, calculation and analysis of the damage variable of circulating soaked rock samples were taken, with sonic measurement results and the empirical formula, the damage variable formulas associated with cycle times was established. The results showed that： the attenuation of sonic velocity basically in line with the exponential relationship, with cycle times increasing; The results of the critical calculation of damage variables and the strength test are well matched, which further confirms that the occurrence and expansion of new crack inside the rock mass resulted from circulating soaked lead to the decrease of the rock strength; The trend of sonic parameters attenuation and damage variable growth are good correspondence.展开更多
基金Project supported by the Foundation of Shenyang Experimental Station of Ecology, Chinese Academy of Sciences (No. SYZ0203).
文摘A field experiment was conducted at the Shenyang Experimental Station ofEcology, Chinese Academy of Sciences, to study the effects of soil management practices on water useand rice (Oryza sativa L.) yield in an aquic brown soil during 2001 and 2002. A completely randomexperimental design with three replications was employed, having four soil management practices astreatments, namely: an undisturbed plow layer (CK), a thin plastic film (TN), a thick plastic film(TI) and subsoil compacting (CP). Results indicated no significant differences among all treatmentsfor rice biomass and grain yields. Also, water consumption was about the same for treatments TN andCK, however the treatments TI and CP were much lower with more than 45% and 40% of the irrigationwater in the treatments TI and CP, respectively, saved each year compared to CK. Therefore, wateruse efficiency was higher in the treatments TI and CP. These results will provide a scientific basisfor the water-saving rice cultivation.
文摘Circulating soaked sandstone and mudstone samples sonic parameters were tested and analyzed, using RSM-SY5 sonic instrument, the variation between soaked times and the velocity of longitudinal wave and shear wave was studied, calculation and analysis of the damage variable of circulating soaked rock samples were taken, with sonic measurement results and the empirical formula, the damage variable formulas associated with cycle times was established. The results showed that： the attenuation of sonic velocity basically in line with the exponential relationship, with cycle times increasing; The results of the critical calculation of damage variables and the strength test are well matched, which further confirms that the occurrence and expansion of new crack inside the rock mass resulted from circulating soaked lead to the decrease of the rock strength; The trend of sonic parameters attenuation and damage variable growth are good correspondence.
