白洋淀水温变化规律研究

依据白洋淀数字化地形图，结合白洋淀地区年平均气温变化数据，对白洋淀的水温变化规律进行了数值模拟。模拟表明：在水生生物最佳生长水位时（以大沽高程8．0m为例），（1）白洋淀水温在水平方向上（表层以下）分布具有差异，8月前，浅水区水温较高，深水区水温较低。8月后，水平温度分布不再有差异。（2）水温垂向分布呈现分层现象。7月下旬前，垂向分层由不规则逐渐向具有规则性发展，深水区分层数稍多于浅水区分层，7月底8月初，分层极具规则性。8月中旬，垂向水温达到一致，没有分层现象，9月后，又出现新的分层．（3）表底温差在8月初一直存在，浅水区表底温差小于深水区的。8月中旬，表底温差消失，9月初重新出现。（4）从动力学、热力学的角度研究了白洋淀的水温变化规律。

Study of water temperature variation in Baiyangdian Lake

A simulation of water temperature variation in Baiyangdian Lake was carried out based on the digital map of baiyangdian topography and the average air temperature of local area at the water level of 8.0m.And some important conclusions were obtained as follows.(1) There is a difference of temperature distribution in horizontal of each layer under the surface.The temperature is higher in shallow area than that in deep area before August,but after August the difference disappears.(2) The water temperature distribution is stratified in vertical.Before the last ten-day of July,the distribution is varied from irregular to a relative regular one,and the more stratification is formed in deep area than that in shallow area.At the end of July and the beginning of August,the stratification is much regular.At the middle of August the stratification disappears and the water temperature is almost same,but in September the stratification appears again.(3) Temperature difference between surface and bottom exists before August first in both deep area and shallow area,but disappears in the middle ten days of August and again appears in the former ten-day of September.(4)The law of temperature changer in Baiyangdian Lake has been researched with using dynamics and thermodynamics point of view.