[Objective] The aim was to get a high yield and simplify fertilization of summer corn in moisture soils in the east of Henan province. [Method] Effects of slow-release fertilizers special for summer corn on its yield,...[Objective] The aim was to get a high yield and simplify fertilization of summer corn in moisture soils in the east of Henan province. [Method] Effects of slow-release fertilizers special for summer corn on its yield, economic benefits and resistance. [Result] By the slow-release fertilizers containing 45% slow-release nitrogen, thousand-kernel weight and the number of ear went up by 28 g and 16 kernels, respectively. Slow-release fertilizers advanced nutrient uptake by summer corns and kept soil nitrogen balanced. In comparison to local fertilization approach, corn yield grew by 13.5% and net profit went up by 1 920 yuan/hm^2 by same-term application technique of seed ＆ slow-release fertilizer in comparison to local methods. In comparison to normal fertilizers containing the same-quantity nutrients, corn yield grew by 10.3% and net profit by 1 215 yuan/hm^2. [Conclusion] The research provides references for slow-release fertilizer promotion in production of corn in Zhoukou and innovation and integration between agricultural machines and techniques.展开更多
The Fifth-Generation NCAR/Penn State Mesoscale Model (MM5) has been used to investigate the extra-area effects of silver iodide (AgI) seeding on stratiform clouds performed at the supercooled layer.A bulk two-moment m...The Fifth-Generation NCAR/Penn State Mesoscale Model (MM5) has been used to investigate the extra-area effects of silver iodide (AgI) seeding on stratiform clouds performed at the supercooled layer.A bulk two-moment microphysical scheme and the new software package for silver iodide are incorporated in MM5.Extra conservation equations are applied to trace the seeding agent,which is transported along the flow field and interacts with the supercooled cloud fields.In this study,the model was run using three nested grids,with 3.3 km × 3.3 km horizontal resolution in the finest grid.The model results showed that seeding with AgI at the 5 to 15℃ levels had microphysical effects on the simulated clouds and that the simulation produced a longer-lasting seeding effect because of the transport of the seeding agent by upper-level winds.Most of the AgI particles acted as deposition nuclei,and the deposition nucleation process contributed mostly to additional cloud ice formation in this study.The results showed that more precipitation results from seeded than unseeded case,and the precipitation was redistributed downwind of the target.Augmented precipitation (varying from 5% to 25% downwind) was confined in space to within 250 km of the seeding target and in time to the 3-h period after initial seeding.展开更多
Propagation of exotic plant species is found in many regions of Madagascar Island. This work aims to describe the impacts of the propagation of Grevillea banksii on soil microbial activities and on the regeneration of...Propagation of exotic plant species is found in many regions of Madagascar Island. This work aims to describe the impacts of the propagation of Grevillea banksii on soil microbial activities and on the regeneration of two native tree species （Intsia bij＇uga and Dalbergia trichocarpa） in the eastern part of Madagascar. The study was conducted within Ianjomara forest where some types of the vegetation are observed such as an area characterized by grassland （P 1）, by homogeneous population of G. banksii （P2） and by a natural forest composed mainly of L bijuga or D. trichocarpa （P3 and P4）. Structure of mycorrhizal fungi communities and associated microorganisms were described on soils from each study plot. The development of I. b^juga and 1）. trichocarpa, was evaluated 4 months after planting on P1, P2, P3, P4 soils formerly colonized by G. banksii. According to the nutrients availability on each soil type, the development of G. banksii was accompanied or not by a high formation of cluster roots. The authors＇ results also show that soil occupied by G. banksii decreased the global microbial and phosphatase activities of soil especially on soil within a high density of cluster roots. Moderately mycotrophic, G. banksii disturbs the structure and the dynamics of symbiotic microflora such as endomycorrhizal fungi （MA） and rhizobia associated with the two native tree species. The findings illustrate the negative impact of G. banksii propagation on the regeneration and the conservation of native tree species in Madagascarian forest.展开更多
Farmers dressed in traditional clothing participate in a ceremony marking the beginning of spring planting in Nedong County,southwest China’s Tibet Autonomous Region,on March 16.
基金Supported by National Project of Soil Testing and Formulated FertilizationKingenta Project~~
文摘[Objective] The aim was to get a high yield and simplify fertilization of summer corn in moisture soils in the east of Henan province. [Method] Effects of slow-release fertilizers special for summer corn on its yield, economic benefits and resistance. [Result] By the slow-release fertilizers containing 45% slow-release nitrogen, thousand-kernel weight and the number of ear went up by 28 g and 16 kernels, respectively. Slow-release fertilizers advanced nutrient uptake by summer corns and kept soil nitrogen balanced. In comparison to local fertilization approach, corn yield grew by 13.5% and net profit went up by 1 920 yuan/hm^2 by same-term application technique of seed ＆ slow-release fertilizer in comparison to local methods. In comparison to normal fertilizers containing the same-quantity nutrients, corn yield grew by 10.3% and net profit by 1 215 yuan/hm^2. [Conclusion] The research provides references for slow-release fertilizer promotion in production of corn in Zhoukou and innovation and integration between agricultural machines and techniques.
基金supported by the National Natural Science Foundation of China (Grant No. 40805056)the National Key Technologies R&D Program of China (Grant No. 2006BAC12B00)
文摘The Fifth-Generation NCAR/Penn State Mesoscale Model (MM5) has been used to investigate the extra-area effects of silver iodide (AgI) seeding on stratiform clouds performed at the supercooled layer.A bulk two-moment microphysical scheme and the new software package for silver iodide are incorporated in MM5.Extra conservation equations are applied to trace the seeding agent,which is transported along the flow field and interacts with the supercooled cloud fields.In this study,the model was run using three nested grids,with 3.3 km × 3.3 km horizontal resolution in the finest grid.The model results showed that seeding with AgI at the 5 to 15℃ levels had microphysical effects on the simulated clouds and that the simulation produced a longer-lasting seeding effect because of the transport of the seeding agent by upper-level winds.Most of the AgI particles acted as deposition nuclei,and the deposition nucleation process contributed mostly to additional cloud ice formation in this study.The results showed that more precipitation results from seeded than unseeded case,and the precipitation was redistributed downwind of the target.Augmented precipitation (varying from 5% to 25% downwind) was confined in space to within 250 km of the seeding target and in time to the 3-h period after initial seeding.
文摘Propagation of exotic plant species is found in many regions of Madagascar Island. This work aims to describe the impacts of the propagation of Grevillea banksii on soil microbial activities and on the regeneration of two native tree species （Intsia bij＇uga and Dalbergia trichocarpa） in the eastern part of Madagascar. The study was conducted within Ianjomara forest where some types of the vegetation are observed such as an area characterized by grassland （P 1）, by homogeneous population of G. banksii （P2） and by a natural forest composed mainly of L bijuga or D. trichocarpa （P3 and P4）. Structure of mycorrhizal fungi communities and associated microorganisms were described on soils from each study plot. The development of I. b^juga and 1）. trichocarpa, was evaluated 4 months after planting on P1, P2, P3, P4 soils formerly colonized by G. banksii. According to the nutrients availability on each soil type, the development of G. banksii was accompanied or not by a high formation of cluster roots. The authors＇ results also show that soil occupied by G. banksii decreased the global microbial and phosphatase activities of soil especially on soil within a high density of cluster roots. Moderately mycotrophic, G. banksii disturbs the structure and the dynamics of symbiotic microflora such as endomycorrhizal fungi （MA） and rhizobia associated with the two native tree species. The findings illustrate the negative impact of G. banksii propagation on the regeneration and the conservation of native tree species in Madagascarian forest.
文摘Farmers dressed in traditional clothing participate in a ceremony marking the beginning of spring planting in Nedong County,southwest China’s Tibet Autonomous Region,on March 16.
