辽河三角洲对虾塘湿地水环境特征

<title>ter Environmental Characteristics of Prawn Ponds Wetland in the Liaohe Delta

2003年6～8月,对辽河三角洲营口沿海的海水、海淡水和淡化等3种对虾养殖塘湿地水化学、生物学特征及化学污染状况进行了调查.结果表明,明水期虾塘水质基本良好,属中营养前期一中营养后期水平,符合地面水环境质量二级标准和渔业水质标准.其透明度均值40～80cm,pH均值7.8～8.6,水温均值21～28℃,离子系数1～4,溶解氧丰富,属中性偏碱性水.水质阴、阳离子组成均分别以Cl-、K++Na+为主,水化学类型为Cl--Na+型,与天然海水相同.水层氮、磷含量较高,但比例不平衡.浮游植物生物量均值3.84×107～2.89×107细胞/L,浮游动物120.3～465.5个/L,其种类组成符合天然海水组成规律,细菌总数均值3.23×104～6.25×104个/L.石油类、挥发酚、铜、砷含量有一定程度超标.不同虾塘水体理化指标有所差异,但不明显.探讨了水质特征、主要理化指标、营养状况与对虾养殖业的相关性和内陆碳酸盐型盐碱水域养殖对虾的可能性.

<abstract>r the sake of understanding the water environmental characteristics of prawn ponds wetland and the change law of water quality, physic-chemical and biology characteristics and chemical pollution situation of prawn ponds wetland for the seawater, the seawater-freshwater and desalination in the Yingkou City of the Liaohe Delta were studied from June to August, 2003. The results showed as follows: Three kinds of prawnponds wetland have good water quality, transparency 40 ~ 80 cm, pH value 7.8 ~ 8.6, water temperatures 21~28℃, and M/D value 1-4, dissolved oxygen was rich, and the water type belongs to Cl- - Na+ and medium-sized soft water or hard water and most one. Take Cl and (K+ + Na+ ) as the principal composition in anion and cation of water chemistry, respectively, the compositions of water chemical ions and water type were the same with the natural seawater. The contents of major nutrient elements were high, the content of TN in prawn pond of desalination was 0.693 -5.61 mg/L, one by seawater and seawater-freshwater were 0. 101 ~ 0.215 mg/L, and the average content of phosphate was lower. The composition proportion of nitriqen and phosphate were not balance on three kinds of prawn ponds waters. N/P value was 2.6-3.2 in prawn ponds of the seawater and the seawater-freshwater, and was 14.4 - 53 .3 in prawn ponds waters of the desalination. In prawn ponds of the seawater, the seawater-freshwater, the average biomass of phytoplankton was 3.84×106 2.89×107 cells/L, the average biomass of zooplankton and bacteria-plankton were 120.3 ~ 465. 5/L and 3.23×104 - 6.25×104/L, respectively. There were changes of the physic-chemical characteristics of different waters of prawn ponds, but changes were not occur red markedly. The water quality changes of different types of prawn ponds and major physic-chemical factors, nutrient state and the correlation to prawn culture were discussed and assessed. Possibility of transplanting prawn was preliminary studied in carbonate saline-alkaline waters. The salinity was not the limiting factor on transplanting prawn in carbonate saline-alkaline waters, high carbonate-alkalinity and pH, as well as the disequilibrium between the composition proportion of major water chemical ions and the differences in water quality type were all the insurmountable obstacles at the moment.