This paper compares two reef sites near Discovery Bay, Jamaica, Dairy Bull and Dancing Lady, from 2000 to 2015. At Dairy Bull reef, with low macroalgal cover (8% in 2002 falling to 1% in 2015) and significant number o...This paper compares two reef sites near Discovery Bay, Jamaica, Dairy Bull and Dancing Lady, from 2000 to 2015. At Dairy Bull reef, with low macroalgal cover (8% in 2002 falling to 1% in 2015) and significant number of Diadema antillarum urchins (c. 5 m<sup>-2</sup>), live coral cover increased from 13% ± 5% in 2006 after the bleaching event in 2005, to 31% ± 7% in 2008, while live Acropora cervicornis increased from 2% ± 2% in 2006 to 28% ± 5% in 2015. Coral cover levels were at least maintained until 2015, owing mostly to a slight increase in A. cervicornis. Dancing Lady reef however was dominated by macroalgae throughout this period (cover of c. 76% ± 7%), with no D. antillarum and showed little decrease in the already low (6% ± 1%) coral cover in 2005. Growth rates for Siderastrea siderea were similar for both sites (7 mm·yr<sup>-1</sup>), while growth rates of A. cervicornis and A. palmata were 120.0 ± 30 mm·yr<sup>-1</sup> and 71.0 ± 29 mm·yr<sup>-1</sup> respectively at Dairy Bull in 2015. At Dancing Lady reef, A. cervicornis colonies which were present from 2003 to 2005 had disappeared in 2006, possibly as a result of the mass bleaching event. It appears that A. cervicornis was the most impacted species during the 2005 bleaching event, but was also the species that recovered fastest after its decline at Dairy Bull.展开更多
Discharging untreated wastewater causes environmental pollution.This research examined the efficiency of removal and the adsorption process of Emerging Contaminant nonylphenol(NP)using magnetic Chlorella vulgaris(M-Ch...Discharging untreated wastewater causes environmental pollution.This research examined the efficiency of removal and the adsorption process of Emerging Contaminant nonylphenol(NP)using magnetic Chlorella vulgaris(M-Chlorella vulgaris).The characterization of M-Chlorella vulgaris involved XRD,FESEM,EDS-Mapping,BET,FTIR,and VSM analyses.The impact of four different parametersdpH,MChlorella vulgaris dose,initial concentration of NP,and contact time on the biosorption process was investigated.To model and optimize the study while minimizing costs and the number of experiments,Response Surface Methodology(RSM)with Central Composite Design(CCD)was employed.According to the findings,the quadratic model with adjusted R^(2)=0.96 was the best fitted among the other models.With pH=3.5,dosage=2.5 g/l,NP concentration=4 mg/l,and reaction time=70 min,which are the optimal parameters,the maximum removal effectiveness was about 91%.The Langmuir model(R^(2)=0.998)and pseudo-second-order model(R^(2)=0.997)exhibited the best fits for the adsorption isotherm and kinetic studies,respectively.The characteristics of M-Chlorella vulgaris were determined to facilitate a spontaneous nature,and thermodynamic experiments indicated that the process of adsorption of nonylphenol is exothermic.The inexpensiveness and availability of adsorbent,suitable efficiency in the biosorption of pollutant and magnetic collection of pollutant from the aquatic environment can be mentioned as the advantages of this process.展开更多
文摘This paper compares two reef sites near Discovery Bay, Jamaica, Dairy Bull and Dancing Lady, from 2000 to 2015. At Dairy Bull reef, with low macroalgal cover (8% in 2002 falling to 1% in 2015) and significant number of Diadema antillarum urchins (c. 5 m<sup>-2</sup>), live coral cover increased from 13% ± 5% in 2006 after the bleaching event in 2005, to 31% ± 7% in 2008, while live Acropora cervicornis increased from 2% ± 2% in 2006 to 28% ± 5% in 2015. Coral cover levels were at least maintained until 2015, owing mostly to a slight increase in A. cervicornis. Dancing Lady reef however was dominated by macroalgae throughout this period (cover of c. 76% ± 7%), with no D. antillarum and showed little decrease in the already low (6% ± 1%) coral cover in 2005. Growth rates for Siderastrea siderea were similar for both sites (7 mm·yr<sup>-1</sup>), while growth rates of A. cervicornis and A. palmata were 120.0 ± 30 mm·yr<sup>-1</sup> and 71.0 ± 29 mm·yr<sup>-1</sup> respectively at Dairy Bull in 2015. At Dancing Lady reef, A. cervicornis colonies which were present from 2003 to 2005 had disappeared in 2006, possibly as a result of the mass bleaching event. It appears that A. cervicornis was the most impacted species during the 2005 bleaching event, but was also the species that recovered fastest after its decline at Dairy Bull.
文摘Discharging untreated wastewater causes environmental pollution.This research examined the efficiency of removal and the adsorption process of Emerging Contaminant nonylphenol(NP)using magnetic Chlorella vulgaris(M-Chlorella vulgaris).The characterization of M-Chlorella vulgaris involved XRD,FESEM,EDS-Mapping,BET,FTIR,and VSM analyses.The impact of four different parametersdpH,MChlorella vulgaris dose,initial concentration of NP,and contact time on the biosorption process was investigated.To model and optimize the study while minimizing costs and the number of experiments,Response Surface Methodology(RSM)with Central Composite Design(CCD)was employed.According to the findings,the quadratic model with adjusted R^(2)=0.96 was the best fitted among the other models.With pH=3.5,dosage=2.5 g/l,NP concentration=4 mg/l,and reaction time=70 min,which are the optimal parameters,the maximum removal effectiveness was about 91%.The Langmuir model(R^(2)=0.998)and pseudo-second-order model(R^(2)=0.997)exhibited the best fits for the adsorption isotherm and kinetic studies,respectively.The characteristics of M-Chlorella vulgaris were determined to facilitate a spontaneous nature,and thermodynamic experiments indicated that the process of adsorption of nonylphenol is exothermic.The inexpensiveness and availability of adsorbent,suitable efficiency in the biosorption of pollutant and magnetic collection of pollutant from the aquatic environment can be mentioned as the advantages of this process.
