In this paper, we use CEVSA, a process-based model, which has been validated on regional and global scales, to explore the temporal and spatial patterns of Net Primary Productivity (NPP) a...In this paper, we use CEVSA, a process-based model, which has been validated on regional and global scales, to explore the temporal and spatial patterns of Net Primary Productivity (NPP) and its responses to interannual climate fluctuations in China's terrestrial ecosystems over the period 1981-1998. The estimated results suggest that, in this study period, the averaged annual total NPP is about 3.09 Gt C/yr -1 and average NPP is about 342 g C/m 2 . The results also showed that the precipitation was the key factor determining the spatial distribution and temporal trends of NPP. Temporally, the total NPP exhibited a slowly increasing trend. In some ENSO years (e.g. 1982, 1986, 1997) NPP decreased clearly compared to the previous year, but the relationship between ENSO and NPP is complex due to the integrated effects of monsoons and regional differentiation. Spatially, the relatively high NPP occurred at the middle high latitudes, the low latitudes and the lower appeared at the middle latitudes. On national scale, precipitation is the key control factor on NPP variations and there exists a weak correlation between NPP and temperature, but regional responses are greatly different.展开更多
A capillary electrophoresis (CE) method has been firstly used for the separation of the therapeutically important xanthones from Securidaca inappendiculata. The separation of the nine xanthones was systematically opt...A capillary electrophoresis (CE) method has been firstly used for the separation of the therapeutically important xanthones from Securidaca inappendiculata. The separation of the nine xanthones was systematically optimized with respect to pH, concentration of running buffers, addition of sulfated b-CD, applied voltage and column temperature. Baseline separation was achieved for the nine xanthones in less than 15 minutes using a background electrolyte consisting of 200 mmol/L borate (pH 9.5) and 10 mmol/L sulfated b-CD.展开更多
Thirty lines of bean were tested for resistance to glyphosate in the field.Obvious difference in resistance response to glyphosate was detected when glyphosate was applied at the rate of 1kg ai/ha on the 15th day afte...Thirty lines of bean were tested for resistance to glyphosate in the field.Obvious difference in resistance response to glyphosate was detected when glyphosate was applied at the rate of 1kg ai/ha on the 15th day after emergence of seedlings.The ling 89-05 showed high resistance with a survival of 77%.Even after glyphosate was reapplied,the survival rats was still 20%.Obvious segregation was found in Progency of 89-05 for resistance to glyphosate;the survival rate of lined 89-05-1 89-05-2 and 89-05-3 were,respectively.42.3%,51.4% and 85.7% at 1kg ai/ha of the herbicide.Progenies 89-05-3 continued to show resistance and lines 89-05-3-5 and 89-05-3-7 both had a survival rate of 100%.When glyphosate was applied with a rate over 1kg ai/ha, the survival rate of the 89-05 -3- 5 was still between 50%-98%.展开更多
基金Knowledge Innovation Project of IGSNRR CAS No.CXIOG-E01-02-04
文摘In this paper, we use CEVSA, a process-based model, which has been validated on regional and global scales, to explore the temporal and spatial patterns of Net Primary Productivity (NPP) and its responses to interannual climate fluctuations in China's terrestrial ecosystems over the period 1981-1998. The estimated results suggest that, in this study period, the averaged annual total NPP is about 3.09 Gt C/yr -1 and average NPP is about 342 g C/m 2 . The results also showed that the precipitation was the key factor determining the spatial distribution and temporal trends of NPP. Temporally, the total NPP exhibited a slowly increasing trend. In some ENSO years (e.g. 1982, 1986, 1997) NPP decreased clearly compared to the previous year, but the relationship between ENSO and NPP is complex due to the integrated effects of monsoons and regional differentiation. Spatially, the relatively high NPP occurred at the middle high latitudes, the low latitudes and the lower appeared at the middle latitudes. On national scale, precipitation is the key control factor on NPP variations and there exists a weak correlation between NPP and temperature, but regional responses are greatly different.
基金The authors would like to acknowledge Agilent Technologies for providing the capillary electrophoresis system and Bioanalytical System for present of sulfated b-CD. The study is supported by NSFC Grant No. 29875001.
文摘A capillary electrophoresis (CE) method has been firstly used for the separation of the therapeutically important xanthones from Securidaca inappendiculata. The separation of the nine xanthones was systematically optimized with respect to pH, concentration of running buffers, addition of sulfated b-CD, applied voltage and column temperature. Baseline separation was achieved for the nine xanthones in less than 15 minutes using a background electrolyte consisting of 200 mmol/L borate (pH 9.5) and 10 mmol/L sulfated b-CD.
文摘Thirty lines of bean were tested for resistance to glyphosate in the field.Obvious difference in resistance response to glyphosate was detected when glyphosate was applied at the rate of 1kg ai/ha on the 15th day after emergence of seedlings.The ling 89-05 showed high resistance with a survival of 77%.Even after glyphosate was reapplied,the survival rats was still 20%.Obvious segregation was found in Progency of 89-05 for resistance to glyphosate;the survival rate of lined 89-05-1 89-05-2 and 89-05-3 were,respectively.42.3%,51.4% and 85.7% at 1kg ai/ha of the herbicide.Progenies 89-05-3 continued to show resistance and lines 89-05-3-5 and 89-05-3-7 both had a survival rate of 100%.When glyphosate was applied with a rate over 1kg ai/ha, the survival rate of the 89-05 -3- 5 was still between 50%-98%.
