Surface water quality may change in the future due to climatic variability as natural processes will most likely be modified by anthropogenic activities. As such, stream temperature is very likely to change as well wh...Surface water quality may change in the future due to climatic variability as natural processes will most likely be modified by anthropogenic activities. As such, stream temperature is very likely to change as well which will impact on surface water quality and aquatic ecosystem dynamics. The present study focused on improving modelling of surface water quality indices and water quality parameters under various climate change scenarios in relationship with stream temperature. Future climate data were extracted from the Canadian Coupled General Climate Model (CGCM 3.1/ T63) under the greenhouse emission scenarios B1 and A2, as defined by the Intergovernmental Panel on Climate Change (IPCC). This study illustrates the usefulness of the stream temperature models, coupled with Climate Change Scenarios to predict the evolution of future stream water temperature regimes and associated biogeochemical water quality parameters pertaining to drinking water quality. The specific objectives of the present study were to analyze the surface water quality of 15 rivers in New Brunswick (Canada) on the basis of 9 parameters under climate change. A Weighed Method and the Canadian Council of Ministers of the Environment (CCME) Method were used to assess the water quality for each river under present and future climate. The knowledge gained from this study will enable engineers and water resources managers to better understand river thermal regimes and climate change impact on water quality related to Drinking Surface Water.展开更多
[Objective] This research was to provide technical guidance for the cultivation of high-quality tobacco in Qianxinan area.[Method] Through analyzing the conditions of main tobacco cultivation areas in Qianxinan includ...[Objective] This research was to provide technical guidance for the cultivation of high-quality tobacco in Qianxinan area.[Method] Through analyzing the conditions of main tobacco cultivation areas in Qianxinan including temperature,precipitation and sunshine,the influence factors of tobacco yield and quality in Qianxinan were investigated.[Result] The altitude of Division I was 450-1 650 m,its days with temperature equal to or higher than 20℃ were about 80 d,its active accumulated temperature was 1 200-2 100℃ and its annual average temperature was 13.5-14.6℃.The altitude of Division II was 1 300-1 450 m,its days with temperature equal to or higher than 20℃ were about 110 d,its active accumulated temperature was 2 100-2 700℃ and its annual average temperature was 14.6-16.3℃.The altitude of Division III was 1 050-1 300 m,its days with temperature equal to or higher than 20℃ were about 150 d,its active accumulated temperature was 2 700-3 600℃ and its annual average temperature was 16.3-17.0℃.Division IV was divided into 2 areas,the altitude of Area 1 was lower than 1 000 m,its days with temperature equal to or higher than 20℃ were more than 160 d,its active accumulated temperature was higher than 3 600℃ and its annual average temperature was higher than 17.5℃;the altitude of Area 2 was higher than 1 700 m,its days with temperature equal to or higher than 20℃ were basically none and its annual average temperature was lower than 1.30℃.[Conclusion] In this research,the agricultural climate index conditions for cultivation of high-quality tobacco in areas at different altitudes were suggested and some references were provided for developing tobacco production in Guizhou.展开更多
Logistic and exponential approaches have been used to simulate plant growth and leaf area index (LAI) in different growing conditions. The objective of the present study was to develop and evaluate an approach to simu...Logistic and exponential approaches have been used to simulate plant growth and leaf area index (LAI) in different growing conditions. The objective of the present study was to develop and evaluate an approach to simulate maize LAI that expresses key physiological and phonological processes using a minimum entry requirement for Quality Protein maize (QPM) varieties grown in the southwestern region of the DR-Congo. Data for the development and testing of the model were collected manually in experimental plots using a non-destructive method. Simulation results revealed measurable variations between crop seasons (long season A and short season B) and between the two varieties (Mudishi-1 and Mudishi-3) for height, number of visible leaves, and LAI. For both seasons, Mudishi-3, a short stature variety was associated with expected stable yield based on simulation data. In general, the model simulated reliably all the parameters including the LAI. The LAI value for mudishi-1 was higher than that of Mudishi-3. There were significant differences among the model parameters (K, Ti, a, b, Tf) and between the two varieties. In all crop conditions studied and for the two varieties, the senescence rate (a) was higher, while the growth rate (b) was lower compared to the estimates based on the STICS model.展开更多
文摘Surface water quality may change in the future due to climatic variability as natural processes will most likely be modified by anthropogenic activities. As such, stream temperature is very likely to change as well which will impact on surface water quality and aquatic ecosystem dynamics. The present study focused on improving modelling of surface water quality indices and water quality parameters under various climate change scenarios in relationship with stream temperature. Future climate data were extracted from the Canadian Coupled General Climate Model (CGCM 3.1/ T63) under the greenhouse emission scenarios B1 and A2, as defined by the Intergovernmental Panel on Climate Change (IPCC). This study illustrates the usefulness of the stream temperature models, coupled with Climate Change Scenarios to predict the evolution of future stream water temperature regimes and associated biogeochemical water quality parameters pertaining to drinking water quality. The specific objectives of the present study were to analyze the surface water quality of 15 rivers in New Brunswick (Canada) on the basis of 9 parameters under climate change. A Weighed Method and the Canadian Council of Ministers of the Environment (CCME) Method were used to assess the water quality for each river under present and future climate. The knowledge gained from this study will enable engineers and water resources managers to better understand river thermal regimes and climate change impact on water quality related to Drinking Surface Water.
基金Supported by Technology Department in Guizhou Province[Guizhou Science Poverty Alleviation(2007) 4001]2006 Science and Technology Project of Tobacco Company in Guizhou Province[Guizhou Tobacco Science (2006) No. 10 ]2006 Meteorological Science and Technology Open Fund Project of Meteorological Bureau in Guizhou Province
文摘[Objective] This research was to provide technical guidance for the cultivation of high-quality tobacco in Qianxinan area.[Method] Through analyzing the conditions of main tobacco cultivation areas in Qianxinan including temperature,precipitation and sunshine,the influence factors of tobacco yield and quality in Qianxinan were investigated.[Result] The altitude of Division I was 450-1 650 m,its days with temperature equal to or higher than 20℃ were about 80 d,its active accumulated temperature was 1 200-2 100℃ and its annual average temperature was 13.5-14.6℃.The altitude of Division II was 1 300-1 450 m,its days with temperature equal to or higher than 20℃ were about 110 d,its active accumulated temperature was 2 100-2 700℃ and its annual average temperature was 14.6-16.3℃.The altitude of Division III was 1 050-1 300 m,its days with temperature equal to or higher than 20℃ were about 150 d,its active accumulated temperature was 2 700-3 600℃ and its annual average temperature was 16.3-17.0℃.Division IV was divided into 2 areas,the altitude of Area 1 was lower than 1 000 m,its days with temperature equal to or higher than 20℃ were more than 160 d,its active accumulated temperature was higher than 3 600℃ and its annual average temperature was higher than 17.5℃;the altitude of Area 2 was higher than 1 700 m,its days with temperature equal to or higher than 20℃ were basically none and its annual average temperature was lower than 1.30℃.[Conclusion] In this research,the agricultural climate index conditions for cultivation of high-quality tobacco in areas at different altitudes were suggested and some references were provided for developing tobacco production in Guizhou.
文摘Logistic and exponential approaches have been used to simulate plant growth and leaf area index (LAI) in different growing conditions. The objective of the present study was to develop and evaluate an approach to simulate maize LAI that expresses key physiological and phonological processes using a minimum entry requirement for Quality Protein maize (QPM) varieties grown in the southwestern region of the DR-Congo. Data for the development and testing of the model were collected manually in experimental plots using a non-destructive method. Simulation results revealed measurable variations between crop seasons (long season A and short season B) and between the two varieties (Mudishi-1 and Mudishi-3) for height, number of visible leaves, and LAI. For both seasons, Mudishi-3, a short stature variety was associated with expected stable yield based on simulation data. In general, the model simulated reliably all the parameters including the LAI. The LAI value for mudishi-1 was higher than that of Mudishi-3. There were significant differences among the model parameters (K, Ti, a, b, Tf) and between the two varieties. In all crop conditions studied and for the two varieties, the senescence rate (a) was higher, while the growth rate (b) was lower compared to the estimates based on the STICS model.
