We studied soils from various zones of Zhuyin, a newly built reservoir near Zhuhai city, intended to supply water to the city of Macau. The reservoir bottom, before its first flooding, consisted of several zones including forest, mountains, planting areas and an animal farming district. The release rates of nitrogen and phosphorus of soils from these different regions were estimated in anaerobic condition in the laboratory after a short-term storage in water, using self-designed equipment. The results showed that zonal disparities in nutrient release should be expected. The farm belt and the livestock farm released most nitrogen and phosphorus. The average potential for releasing nitrogen and phosphorus was about 15 g·m-3 and 30 mg·m-3. It is estimated that the amount of nitrogen released is close to 1.7×105 kg while phosphorus release is only about 1.5×103 kg, 10 days after storage. Thus, The phytoplankton in Zhuyin Reservoir was expected to be under phosphorus limitation. Further, the expected concentration of nitrogen and phosphorus could reach high values of about 4.25 mg·L-1 and 0.038 mg·L-1, respectively. Therefore, the nutrient-rich soils of the farm belt and the livestock farm should be removed before water storage, and the other regions should be rendered inactive or capped to reduce the release of nutrients from the sediments.