关键词: 生态补偿, 鱼类行为, 光色选择, 鱼类过坝, 洄游

Abstract: Effects of exogenous melatonin on the growth, physiological indices, and arsenic (As) accumulation of rice under As stress were investigated in solution culture. The results showed that melatonin addition alleviated the toxic effects of As on rice seedlings, and improved plant height, root length, and biomass of rice. Melatonin addition also significantly increased activities of antioxidant enzymes, such as POD, SOD, CAT, decreased MDA content and O₂^-_·producing rate. Compared to single As stress treatment, adding 0.1-100 μmol·L^-1 melatoninsignificantly increased POD activities in leaves and roots by 38.6%-62.9% (except for 0.1 μmol·L^-1 melatonin) and 37.4%-142.6%, SOD activities by 7.9%-27.3% and 63.1%-96.0%, CAT activities by 16.7%-66.7% and 41.6%-151.1%, but decreased MDA content by 24.2%-40.7% and 14.1%-51.9%, and O₂^-_· producing rate by 12.4%-21.7% and 28.3%-68.6%, respectively. Our results confirmed that melatonin addition with suitable concentration could increase the activities of antioxidant enzyme, alleviate lipid peroxidation damage, and improve the resistance of rice to As stress.

Key words: fishes pass through the dam, fish behavior, migratory, ecological compensation., light trap