溶解氧对低洼盐碱地鱼塘物质循环的影响

对黄淮海平原低洼盐碱地鱼塘中溶解氧与物质循环之间的关系进行了初步研究. 结果表明池塘水体中的溶解氧含量取决于水体中藻类的光合作用及其它生物的耗氧作用扰动的方式时间可显著改变水体中溶解氧的含量. 池塘水体中异养细菌的数量变动除与水体中的有机物质含量等有关外与水体中溶解氧的含量密切相关. 尤其在底泥中这种变化更加明显. 池塘水体中的氨化作用强度磷的转化强度明显地呈现出受水体中的溶解氧含量影响. 当水体中的溶解氧含量增加时导致细菌的现存量及活性的增加使得氨化作用强度磷的转化强度也显著增加这种情况在底泥中表现的更加明显. 池塘水体中反硝化作用强度反硫化作用强度的变化则与水体中溶解氧含量的变化相反. 当水体中溶解氧的含量减少时水体中的反硝化作用强度反硫化作用强度反而大大增加. 这种作用在底泥中表现得也非常明显.

Effect of Dissolved Oxygen on the Nutrient Cycle in Low-wetland Fishponds

The relationship between dissolved oxygen and nutrient cycle in low-wetland fishponds of the Huanghe-Huaihe-Haihe plain was studied. The results show that: 1) The dissolved oxygen content depended on the photosynthesis of algae and the consumption of other organisms, which can be significantly improved by mixing. 2) The heterotrophic bacteria number of pond water was correlation with organic matter in addition to the dissolved oxygen. This change was more clearly especially in the sediments. 3) The dissolved oxygen of pond water significantly affected the changes of ammonification intensity and phosphorous decomposition intensity. When the dissolved oxygen was increased, the heterotrophic bacteria number and active were also improved, which caused the ammonification intensity and phosphorous decomposition intensity was significantly increased. This situation was more clearly in the sediments. 4) The nitrate reduction intensity and sulfate reduction intensity was negative correlation with the dissolved oxygen content. When the dissolved oxygen was decreased, the nitrate reduction intensity and sulfate reduction intensity were significantly increased. This situation also was more clearly in the sediments.