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Monoliths are age-long stone formations that have represented and given clues to the reconstruction and interpretation of the extinct cultures. Their tourism motivation to localities is inestimable. Incidentally, these monumental edifices of human cultural history have faced the challenges of safety and preservation. For example, the Cross River Monoliths have continued to deteriorate and are being destroyed in the recent past due to the activities of man and nature along with other safety issues facing the monoliths, its owners and visitors. Some rescue mechanisms have been employed made in tincluding the assembling of these monoliths to a designated location in an open-air museum. This paper contends that more needs to be done in this regard. The study proposes Mix Method Approach (MMA), which is a conglomeration of interdependent practices, to enhance the safety and preservation of the Cross River monoliths for both posterity and tourism development in the area. The implication of the study is the introduction of further directions in monolith studies and preservations in Africa and beyond.

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Solar disinfection (SODIS) involves exposing water stored in transparent polyethylene terephthalate (PET) containers to the sun for about 6 h of strong sunlight, after which the water is rendered safe for consumption. This study investigated the seasonal effect of reactor characteristics on the inactivation kinetics/constant of faecal coliforms by conducting a 23 factorial experiment, involving two levels of PET bottle size, PET bottle thickness, and PET bottle rear surface, uniquely combined to form 8 SODIS reactors/experimental units. The faecal coliform population of hourly samples taken from the 8 SODIS reactors showed that the inactivation kinetics/constant depends on the irradiation energy and maximum water temperature as dictated by the reactor characteristics. The average rate constant of the reflective reactors (1.37 ± 0.43 h-1) was significantly better (p < 0.001) than the absorptive reactors (1.17 ± 0.59 h-1) between June and October. The average rate constant of the small PET bottles (1.73 ± 0.65 h-1) is significantly higher (p < 0.002) than the large PET bottles (1.46 ± 0.51 h-1) from December to May; while the average rate constant of the light PET bottles (1.58 ± 0.64 h-1) is significantly better (p < 0.001) than the thick PET bottles (1.41 ± 0.52 h-1) year-round. Analyses of results confirmed a two-way interaction effect between PET bottle size and PET bottle thickness and between PET bottle rear surface and PET bottle thickness for periods with average radiation intensity of  450–500 W∙m−2. Although container size and thickness were the most significant factors, combining light PET bottles with absorptive rear-surface could extend the applicability of SODIS to regions that fall short of the recommended radiation intensity threshold of 500 W∙m−2 for 5 h.

Solar disinfection (SODIS) is an economical and user-friendly method of water purification mostly applied in the tropical countries. SODIS uses the ultraviolet (UV) and temperature effects of the sun to kill pathogens in drinking water. The objective of the study was to develop a functional relationship between pathogen die-off rate and SODIS treatment conditions, namely daily maximum of 5-h averages of UV intensity , daily maximum water temperature , and water turbidity . Regression analyses/models based on 5-month data revealed that although and can be excellent predictors of pathogen die-off rate, their variable inflation factors (6.75 and 6.57, respectively), which is a measure of dependence between the two variables and adequacy of the estimated regression coefficients, suggest that they cannot be successfully combined in a single least-square regression model. was found to be a better predictor of in SODIS than . Water turbidities in the range of 1–30 NTU had no significant effect on the pathogen die-off rate. The study concluded that regression models/analyses can be successfully employed to explain the day-to-day variability in pathogen die-off rate, predict SODIS applicability, and exposure period in different regions of the world based on UV, water temperature, and water turbidity.