对虾精养池塘碳、氮和异养细菌含量的变化及其相关性研究

Variation in contents of carbon,nitrogen and heterotrophic bacteria in intensive shrimp ponds and their correlation

文章调查了广东省汕尾市红海湾对虾精养池塘水体中不同形式的碳(C)、氮(N)和异养细菌含量的变化,并分析C和N对异养细菌的影响,以期为养殖过程合理调控水质环境提供理论数据。结果发现,池塘中不同形式的ρ(C)在养殖前、中期逐渐升高并达到最大值,中、后期缓慢下降趋于稳定,ρ(N)在养殖前、中期较低,后期升高并达到最大值;异养细菌数在养殖中期的第56天和养殖后期的第98天出现2个高峰,养殖第70天出现低谷。异养细菌数与总无机碳(TIC)和总碳(TC)呈现极显著正相关关系;养殖中、后期异养细菌数与C/N(TOC/TN)呈极显著负相关关系。结果表明,养殖中、后期水体中C(主要是有机碳)成为影响异养细菌繁殖的限制性因素,适当添加C源可以促进异养细菌繁殖,吸收转化无机氮,从而达到降低水体中无机氮浓度、提高物质循环利用效率的作用。

We studied the variation in contents of carbon （C） , nitrogen （N） and heterotrophic bacteria in the intensive shrimp ponds in Shanwei Red Bay of Guangdong Province, and analyzed the effects of C and N on heterotrophic bacteria, so as to provide theoretical references for a reasonable regulation for water quality during culture period. The results show that carbon content gradually reaches the maximum during pre- and mid-culture periods but declines to stability in late period; the nitrogen content is relatively low during pre- and mid-culture periods but reaches the maximum in later period ; the content of heterotrophic bacteria peaks in mid-cuhure period for 56 d and later period for 98 d, but reaches the lowest point after 70-day culture. The heterotrophic bacteria show a very significant positive correlation to TIC and TC. In late culture period, the heterotrophic bacteria show a very significant negative correlation to C/N （TOC/TN）. Mainly carbon limits the propagation of heterotrophic bacteria in mid and late culture periods. Thus, addition of carbon in the ponds can promote propagation of heterotrophic bacteria, absorption and transformation of inorganic nitrogen, and reduce the concentration of inorganic nitrogen, finally imorove the efficiency of material recycling.