Hydrological models are very useful tools for evaluating water resources, and the hydroclimatic hazards associated with the water cycle. However, their calibration and validation require the use of performance criteri...Hydrological models are very useful tools for evaluating water resources, and the hydroclimatic hazards associated with the water cycle. However, their calibration and validation require the use of performance criteria which choice is not straightforward. This paper aims to evaluate the influence of the performance criteria on water balance components and water extremes using two global rainfall-runoff models (HBV and GR4J) over the Ouémé watershed at the Bonou and Savè outlets. Three (3) Efficacy criteria (Nash, coefficient of determination, and KGE) were considered for calibration and validation. The results show that the Nash criterion provides a good assessment of the simulation of the different parts of the hydrograph. KGE is better for simulating peak flows and water balance elements than other efficiency criteria. This study could serve as a basis for the choice of performance criteria in hydrological modelling.展开更多
Length-weight relationships and condition factors are among the commonly used parameters to link the length of a fish to its weight. The present study was initiated to find out the growth patterns and overweight statu...Length-weight relationships and condition factors are among the commonly used parameters to link the length of a fish to its weight. The present study was initiated to find out the growth patterns and overweight status of 15 fish species in the Loémé basin in Mayombe, Republic of Congo. In the period from February 2020 to September 2021, sampling was carried out in eight stations, following a standardised capture method using four gillnets of 10, 12, 15, and 25 mm mesh size and a hawk net of 1.90 m radius with 10 mm mesh size. Length-weight relationships were calculated according to P = aLS<sup>b</sup> and the condition factor, using K = (P/LS<sup>b</sup>)* 100. A total of 1153 specimens representing 15 species, 10 genera and 6 families were recorded. The number of specimens ranged from 10 to 214 for Chrysichthys auratus and Enteromius camptacanthus, respectively. The allometry coefficient b minimum of 2.697 for Chromidotilapiamelaniae and maximum of 3.589 for Garraornata, with a mean of 3.03 ± 0.2 is significantly not different from 3 at the 0.05 probability threshold and indicates isometric growth for almost all species, except for E. camptacanthus where b = 2.858 was statistically different from 3 at the same threshold. The positive and high values of the coefficients of determination r<sup>2</sup> = 0.787-0.989 of the species, obtained during this study, suggest that weight increases with size in the fish of the Loémé basin. The average condition factor varies from 0.524 ± 0.064 for G. ornata to 4.917 ± 0.440 for C. melaniae.展开更多
The Northern Shaanxi salt basin locates in the east of the Ordos basin.In this area,the thick layer salt sediment exists in the Majiagou Formation of Ordovician.Especial in the sixth subsection of the Majiagou fifth m...The Northern Shaanxi salt basin locates in the east of the Ordos basin.In this area,the thick layer salt sediment exists in the Majiagou Formation of Ordovician.Especial in the sixth subsection of the Majiagou fifth member,it展开更多
文摘Hydrological models are very useful tools for evaluating water resources, and the hydroclimatic hazards associated with the water cycle. However, their calibration and validation require the use of performance criteria which choice is not straightforward. This paper aims to evaluate the influence of the performance criteria on water balance components and water extremes using two global rainfall-runoff models (HBV and GR4J) over the Ouémé watershed at the Bonou and Savè outlets. Three (3) Efficacy criteria (Nash, coefficient of determination, and KGE) were considered for calibration and validation. The results show that the Nash criterion provides a good assessment of the simulation of the different parts of the hydrograph. KGE is better for simulating peak flows and water balance elements than other efficiency criteria. This study could serve as a basis for the choice of performance criteria in hydrological modelling.
文摘Length-weight relationships and condition factors are among the commonly used parameters to link the length of a fish to its weight. The present study was initiated to find out the growth patterns and overweight status of 15 fish species in the Loémé basin in Mayombe, Republic of Congo. In the period from February 2020 to September 2021, sampling was carried out in eight stations, following a standardised capture method using four gillnets of 10, 12, 15, and 25 mm mesh size and a hawk net of 1.90 m radius with 10 mm mesh size. Length-weight relationships were calculated according to P = aLS<sup>b</sup> and the condition factor, using K = (P/LS<sup>b</sup>)* 100. A total of 1153 specimens representing 15 species, 10 genera and 6 families were recorded. The number of specimens ranged from 10 to 214 for Chrysichthys auratus and Enteromius camptacanthus, respectively. The allometry coefficient b minimum of 2.697 for Chromidotilapiamelaniae and maximum of 3.589 for Garraornata, with a mean of 3.03 ± 0.2 is significantly not different from 3 at the 0.05 probability threshold and indicates isometric growth for almost all species, except for E. camptacanthus where b = 2.858 was statistically different from 3 at the same threshold. The positive and high values of the coefficients of determination r<sup>2</sup> = 0.787-0.989 of the species, obtained during this study, suggest that weight increases with size in the fish of the Loémé basin. The average condition factor varies from 0.524 ± 0.064 for G. ornata to 4.917 ± 0.440 for C. melaniae.
文摘The Northern Shaanxi salt basin locates in the east of the Ordos basin.In this area,the thick layer salt sediment exists in the Majiagou Formation of Ordovician.Especial in the sixth subsection of the Majiagou fifth member,it
