Narrow Results

This study investigates the effect of copper on the germination and growth of watermelon plants. It was found that copper only inhibited the germination and growth of watermelon plants when its concentrations were high. Copper concentrations of either 50 or 100μM increased chlorophyll content in the plants slightly while copper concentrations over 100μM led to an obvious decrease in chlorophyll contents. It is concluded that excess copper significantly affects the germination and growth of watermelon.

To evaluate the toxic effects of environmental contaminant PFOA on green algae, Chlorella pyrenoidosa was exposed to a serial concentaertions of PFOA for proliferation evaluation and physiological status analysis. Within 96h, PFOA doses equal to or over 50 mg/L all inhibited the proliferation speed of Chlorella pyrenoidosa(p<0.05). The 96h- EC₅₀ value of PFOA was determined to be 261.2 mg/L. In a chronic experiment with 8 days of PFOA treatment, all of the treated groups showed decreased Chlorophyll a concentration. PFOA equal to or over 100 mg/L resulted in decreased antioxidant enzymes activity and increased MDA content in Chlorella pyrenoidosa(P<0.05).

The effects of oil water accommodated fraction (WAF), emulsion (DWAF) and dispersants on chlorophyll-a content, protein content and enzymatic activity and of Isochrysis galbana were studied by experimental ecology method with 96 hours. Thee results showed that content of protein and chlorophyll-a were decreased with the extension of time under the three stress. There were significant effects of three solutions on SOD, GSH-PX and MDA. After 96 hours, the lowest content of protein, chlorophyll-a, SOD and GSH-PX, the highest content of MDA were found in WAF group. Therefore WAF stress had the most influential effects on physiological and biochemical characteristics of Isochrysis galbana in the experiment.