Abstract: The Qingzhen chemical industry is an important source of Hg pollution to the Dongmenqiao River, Guizhou Province, southwest China. To evaluate the Hg pollution status of this river, we measured the concentration and distribution of Hg in environmental samples collected from the Dongmenqiao River. The average THg and MeHg concentrations were (135.79±47.40) and (0.64±0.58) ng·L^-1 in river water, (3.38±1.91) mg·kg^-1 and (10.47±0.40) μg·kg^-1 in biofilms, and (23.21±20.22) mg·kg^-1 and (32.74±10.96) μg·kg^-1 in sediments, respectively. To further clarify the risk of mercury on aquatic organisms in this river, embryosand larvae of Oryzias latipes were exposed to different treatments with Hg-ontaminated water, biofilms and sediments collected from the river. After 15 days of exposure, the hatching time of embryos was prolonged, the hatching rate was significantly decreased, and the mortality rate was significantly increased. The results showed the inability of embryos in breaking the membrane, yolk sac edema and other malformation effects, as well as different degrees of malformation of the newly hatched larvae. After 24 h, 48 h, 96 h, and 21 d exposure, the mortality and deformity rates significantly increased with the increasing time of exposure, and a series ofdeformity effects occurred mainly as spinal curvature. Our results indicated that mercury pollution in the Dongmenqiao River may significantly affect the early growth of O. latipes.

Key words: water consumption characteristic, PAR interception and utilization., overwintering stage, winter wheat, supplemental irrigation by measuring soil moisture