CHAPTER 5: GENERAL CONCLUSIONS AND RECOMMENDATIONS
5.2 RECOMMENDATIONS
90 tropical rivers. These results can be used to optimize estimations of downstream toxicity. However, there are certain limitations in this study:
1. Land use percentages in the river basin comparisons may have some effect because the data was collected from different years.
2. The mean value was used to calculate the loading of suspended sediment and nutrients.
3. Pesticide loading was calculated based on three seasons (maximum) per year, and some farmers cultivate four seasons per year.
4. Only four major crops were selected from one farmer, and the mean values were used to calculate pesticide loading.
5. The adsorption experiment was conducted under laboratory conditions (closed environment), and there may be differences when compared with a natural system.
91
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