淡水鱼塘分层水温的变化特征

Variation Characteristics of Water Temperatures at Different Depths of Fishpond

为了指导淡水养殖鱼塘水温的科学调控,保障水体生物安全越冬度夏,笔者选用武汉地区2011年3月至2012年2月淡水养殖鱼塘不同深度的水温数据及对应岸边的气温数据,应用数理统计分析方法分析其在不同时间尺度上的变化规律。结果表明:日尺度下不同深度水温日内的变化趋势与气温一致,气温的振幅较水温大,晴天气温及不同深度水温的振幅明显大于阴天。月尺度下3—7月气温及各层水温总体呈上升趋势,4月各层水温上升最显著;水温随深度增加而降低的趋势在晴天较多云天显著,阴天该趋势不明显。8月至次年2月,气温及各层水温呈下降趋势,1月下降最显著,水温随深度的变化呈降-升-降模式或降-升模式。季节尺度:水温随深度增加而降低的速率从大到小依次为春季、夏季、秋季,冬季水温随深度增加呈降-升-降模式。该结果可为武汉养殖池塘科学管理提供指导,也可为养殖鱼塘水温预报奠定基础。

In order to ensure the creatures safe living through winter and summer by scientific regulation ofwater temperature of fishpond, water temperatures of different vertical layers of fishpond and the shore airtemperature were researched at different time scales from March 2011 to February 2012 in Wuhan. The resultsshowed that diurnal change trend of water temperatures at different depths of the fishpond was in consistentwith that of the shore air temperature which had relatively smaller amplitude. The amplitude of air temperatureand water temperature of each layer under clear weather was significantly greater than that of cloudy days.Monthly averaged air temperature and water temperature of each layer increased from March to July, especiallyin April. Water temperature decreasing with increasing depth was significantly obvious under clear weatherthan that under cloudy days. The monthly averaged air temperature and water temperature of each layerdecreased from August to February of the next year, especially in January. The variation of water temperaturewith depth took on fall- rise- fall or fall- rise modes. On the seasonal scale, the decreasing rate of watertemperature with increasing depth decreased from spring to autumn. Water temperature with increasing depthpresented a fall-rise-fall mode in winter. The results could provide guidance for the scientific management offish ponds in Wuhan, and could also lay foundation of water temperature forecast for aquaculture.