Monday River, at Eastern Paraguay is located south of the Itaipu Dam, and discharges into the Paraná River. At the point of discharge it has been projected to build a Hydroelectric power Plant and the reservoir w...Monday River, at Eastern Paraguay is located south of the Itaipu Dam, and discharges into the Paraná River. At the point of discharge it has been projected to build a Hydroelectric power Plant and the reservoir will extend upstream the Monday. As a result of the impoundment of a river, the flooded soil can provide a certain amount of nutrients into the aqueous medium setting new conditions for aquatic life and affecting to a greater or lesser degree the ecosystems. The aim of this work is the assessment of the impact on the water quality of the incorporation of major nutrients into the water body after damming Monday River. Samples from soil profiles were taken at selected sites on both banks of the river;the amount of phosphorus, nitrogen, potassium, calcium and magnesium as well as other parameters as pH, organic matter, exchangeable bases were determined using standard procedures. Granulometric analysis was also performed. Phosphorus availability was determined by isotopic exchange. In addition the samples were submitted to submersion/incubation experiments along 60 days, and the concentration of elements incorporated into the water analyzed. Results show that flooded soils are low in phosphorus and nitrogen which is scarce in some cases;so does other nutrients. Submersion experiments also indicate generally limited incorporation of such nutrients into the water body. Significant negative impact of these soils on the water quality of the reservoir cannot be expected.展开更多
文摘Monday River, at Eastern Paraguay is located south of the Itaipu Dam, and discharges into the Paraná River. At the point of discharge it has been projected to build a Hydroelectric power Plant and the reservoir will extend upstream the Monday. As a result of the impoundment of a river, the flooded soil can provide a certain amount of nutrients into the aqueous medium setting new conditions for aquatic life and affecting to a greater or lesser degree the ecosystems. The aim of this work is the assessment of the impact on the water quality of the incorporation of major nutrients into the water body after damming Monday River. Samples from soil profiles were taken at selected sites on both banks of the river;the amount of phosphorus, nitrogen, potassium, calcium and magnesium as well as other parameters as pH, organic matter, exchangeable bases were determined using standard procedures. Granulometric analysis was also performed. Phosphorus availability was determined by isotopic exchange. In addition the samples were submitted to submersion/incubation experiments along 60 days, and the concentration of elements incorporated into the water analyzed. Results show that flooded soils are low in phosphorus and nitrogen which is scarce in some cases;so does other nutrients. Submersion experiments also indicate generally limited incorporation of such nutrients into the water body. Significant negative impact of these soils on the water quality of the reservoir cannot be expected.
