Land use change and cropping patterns are important factors for controlling carbon sequestration in soils and they may also change the relative importance of different mechanisms of soil organic matter stabilization. ...Land use change and cropping patterns are important factors for controlling carbon sequestration in soils and they may also change the relative importance of different mechanisms of soil organic matter stabilization. The study was conducted to investigate the state of carbon sequestration in soil aggregates under different cropping patterns of Khulna, Jessore and Chapainawabganj districts in Bangladesh. Thirty-six soil samples were collected from (0 - 100 cm depth) above mentioned regions of three physiographic regions: Ganges Meander Floodplain, Ganges Tidal Floodplain and High Barind Tract. The texture of the samples varied within three soil texture groups, Silt Loam, Silty Clay Loam and Silty Clay. The highest NSI value (0.89) was found under Wheat-Fallow-T. Aman cropping pattern in Silty Clay soils (sample No 15) and lowest value (0.59) was found Vegetables/Mustard-Fallow-T. Aman cropping pattern in Silt Loam soils (sample No 17). The highest value (735.20 mg<span style="white-space:nowrap;"><span style="white-space:nowrap;">•</span></span>kg<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>1</sup>) of active C was observed under Chickpea/mustard-T. Aman (Sample No 31) and the lowest value (619.23 mg<span style="white-space:nowrap;"><span style="white-space:nowrap;">•</span></span>kg<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>1</sup>) was found in case of Wheat-Fallow-T. Aman cropping pattern (Sample No 30). The highest SOC stock (1.62 Kg C m<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>2</sup>) was found in Silty Clay Loam soil under Mungbean/Ash gourd-T. Aman cropping pattern (Sample no 4) and the lowest SOC stock (0.35 Kg C m<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>2</sup>) was found in Silt Loam soil under Cauliflower/Pumkin/Spinach-T. Aman Cropping pattern (Sample No 2). Soil organic carbon associated with different size aggregates was the highest (3.14%) under Mungbean/Ash gourd-T. Aman (Sample No 20) and was the lowest (0.36%) under Cauliflower/Pumkin/Spinach-T. Aman cropping pattern (Sample No 2). Organic carbon content in aggregate size ranges > 2000 μm (SOC1), 2000 - 250 μm (SOC2), 250-53 μm (SOC3), and <53 μm (SOC4) varied from 0.36% - 1.90%, 0.52% - 2.10%, 0.50% - 2.60% and 0.50% - 1.62%, respectively. The percentages of SOC associated with <53 μm aggregates were higher than those of >2000 μm, 2000 - 250 μm and 250 - 53 μm, aggregates. Significant positive correlations were found between SOC stock and SOC1, SOC stock and SOC2, SOC stock and SOC3, SOC stock and SOC4.展开更多
In coping with the global financial crisis, all levels of the Chinese government and foreign trade firms have not only created new practices but have also changed their goal from transforming the growth pattern of for...In coping with the global financial crisis, all levels of the Chinese government and foreign trade firms have not only created new practices but have also changed their goal from transforming the growth pattern of foreign trade to transforming the development pattern of joreign trade. China＇s experience shows that economic instruments such as Net Barter Terms of Trade （NBTT） and the smile curve theory have limitations when it comes to interpreting foreign trade. If used improperly, scientific theories often lead to.fallacies. Transjbrming the development pattern of China＇s .foreign trade requires the following changes： national income distribution, foreign trade competition, market exploration, and resource utilization. We advise that competent authorities create a reasonable and operational system of assessment indicators.展开更多
Chinese stock market is a developing one. In the present stages, to control scientifically the expansion speed and avoid drastic fluctuations is an important problem. Through analysis of plenty of data of SSE(Shanghai...Chinese stock market is a developing one. In the present stages, to control scientifically the expansion speed and avoid drastic fluctuations is an important problem. Through analysis of plenty of data of SSE(Shanghai Stock Exchange) Index and relevant economic quotas, we find that the problem of predicting SSE Index is a typical multi variable, nonlinear one. On the basis of the analysis, we apply the technology of fuzzy pattern recognition, to the optimum pattern division of SSE Index's time alignments from Jan. of 1993 to Dec. of 1997, and get a balanced pattern of the stock index fluctuation. At the same time, by using database technology, we find the optimum expansion speed of Shanghai stock, which can make SSE Index fluctuate steadily within the balanced area. We verified this model with the latest data and found it coincides with the reality perfectly. So it has the practical value and provides the policy makers with a scientific basis in controlling the expansion pace.展开更多
文摘Land use change and cropping patterns are important factors for controlling carbon sequestration in soils and they may also change the relative importance of different mechanisms of soil organic matter stabilization. The study was conducted to investigate the state of carbon sequestration in soil aggregates under different cropping patterns of Khulna, Jessore and Chapainawabganj districts in Bangladesh. Thirty-six soil samples were collected from (0 - 100 cm depth) above mentioned regions of three physiographic regions: Ganges Meander Floodplain, Ganges Tidal Floodplain and High Barind Tract. The texture of the samples varied within three soil texture groups, Silt Loam, Silty Clay Loam and Silty Clay. The highest NSI value (0.89) was found under Wheat-Fallow-T. Aman cropping pattern in Silty Clay soils (sample No 15) and lowest value (0.59) was found Vegetables/Mustard-Fallow-T. Aman cropping pattern in Silt Loam soils (sample No 17). The highest value (735.20 mg<span style="white-space:nowrap;"><span style="white-space:nowrap;">•</span></span>kg<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>1</sup>) of active C was observed under Chickpea/mustard-T. Aman (Sample No 31) and the lowest value (619.23 mg<span style="white-space:nowrap;"><span style="white-space:nowrap;">•</span></span>kg<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>1</sup>) was found in case of Wheat-Fallow-T. Aman cropping pattern (Sample No 30). The highest SOC stock (1.62 Kg C m<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>2</sup>) was found in Silty Clay Loam soil under Mungbean/Ash gourd-T. Aman cropping pattern (Sample no 4) and the lowest SOC stock (0.35 Kg C m<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>2</sup>) was found in Silt Loam soil under Cauliflower/Pumkin/Spinach-T. Aman Cropping pattern (Sample No 2). Soil organic carbon associated with different size aggregates was the highest (3.14%) under Mungbean/Ash gourd-T. Aman (Sample No 20) and was the lowest (0.36%) under Cauliflower/Pumkin/Spinach-T. Aman cropping pattern (Sample No 2). Organic carbon content in aggregate size ranges > 2000 μm (SOC1), 2000 - 250 μm (SOC2), 250-53 μm (SOC3), and <53 μm (SOC4) varied from 0.36% - 1.90%, 0.52% - 2.10%, 0.50% - 2.60% and 0.50% - 1.62%, respectively. The percentages of SOC associated with <53 μm aggregates were higher than those of >2000 μm, 2000 - 250 μm and 250 - 53 μm, aggregates. Significant positive correlations were found between SOC stock and SOC1, SOC stock and SOC2, SOC stock and SOC3, SOC stock and SOC4.
文摘In coping with the global financial crisis, all levels of the Chinese government and foreign trade firms have not only created new practices but have also changed their goal from transforming the growth pattern of foreign trade to transforming the development pattern of joreign trade. China＇s experience shows that economic instruments such as Net Barter Terms of Trade （NBTT） and the smile curve theory have limitations when it comes to interpreting foreign trade. If used improperly, scientific theories often lead to.fallacies. Transjbrming the development pattern of China＇s .foreign trade requires the following changes： national income distribution, foreign trade competition, market exploration, and resource utilization. We advise that competent authorities create a reasonable and operational system of assessment indicators.
文摘Chinese stock market is a developing one. In the present stages, to control scientifically the expansion speed and avoid drastic fluctuations is an important problem. Through analysis of plenty of data of SSE(Shanghai Stock Exchange) Index and relevant economic quotas, we find that the problem of predicting SSE Index is a typical multi variable, nonlinear one. On the basis of the analysis, we apply the technology of fuzzy pattern recognition, to the optimum pattern division of SSE Index's time alignments from Jan. of 1993 to Dec. of 1997, and get a balanced pattern of the stock index fluctuation. At the same time, by using database technology, we find the optimum expansion speed of Shanghai stock, which can make SSE Index fluctuate steadily within the balanced area. We verified this model with the latest data and found it coincides with the reality perfectly. So it has the practical value and provides the policy makers with a scientific basis in controlling the expansion pace.
