PH AND THE HEAVY MNETALS AL, CU, PB AND ZN

本研究的目的是记录 改变pH值和Al、Cu、Pb、Zn对淡水湖泊的毒性 藻类 我们将重点研究细胞的变化和生长 在存在和不存在的情况下，在不同pH下的藻类的速率 Al、Cu、Pb和Zn。 具体而言，本研究的目的是： 1. 确定将pH值从11.0变为4.0对 选择代表性淡水如藻类的生长。 2. 测定铝、铜、铅、锌在不同pH值下的EC50 在这项研究中使用。 3. 使用形态测定法在不同的时间点测定细胞效应。 测试的pH值以及Al、Cu、Pb和Zn在EC50和1 高于和低于该点的浓度对数。 4. 测定各处理对叶绿素的影响 细胞的内容。 这是对生产力的一个很好的估计。 5. 使用X射线能量色散分析测定， 区室化扫描透射电镜 Al、Cu、Pb和Zn的富集作用。 6. 建立这四种阳离子的毒性等级 在不同的pH值水平，以确定的重要性， 铝是产酸过程中的关键毒物。 我们认为迫切需要阐明酸的影响 雨水冲刷着我们的淡水湖，慢慢地把它们变成了酸 湖泊. 有一组数据似乎缺乏，但至关重要 我们对这个问题的评估是可靠的科学数据， 明确地证明了酸雨的影响，通过 pH值的变化对藻类系统的影响。

It is the purpose of this investigation to document the effects of changing pH and Al, Cu, Pb and Zn toxicity on freshwater lake algae. We will focus the study on cellular changes and the growth rates of the algae at different pH in the presence and absence of Al, Cu, Pb and Zn. Specifically, the objectives of this study are: 1. Determine the effect of changing pH from 11.0 to 4.0 on the growth of selected representative freshwater like algae. 2. Determine the EC50 of Al, Cu, Pb and Zn at the different pHs used in this study. 3. Determine cellular effects using morphometry at the different pHs tested and the effect of Al, Cu, Pb and Zn at the EC50 and one log concentration above and below this point. 4. Determine the effect of each treatment on the chlorophyll content of the cells. This is a good estimate of productivity. 5. Determine using X-ray energy dispersive analysis with a scanning transmission electron microscope if compartmentalization of the Al, Cu, Pb and Zn has occurred. 6. To establish the toxicity hierarchy among these four cations at the varying pH levels in order to determine the importance of Al as a key toxicant in acidogenesis. We feel there is an urgent need to elucidate the impact of acid rain on our freshwater lakes which is slowly turning them into acid lakes. One set of data which seems to be lacking but is critical to our assessment of this problem is solid scientific data which unequivocally demonstrates the suggested effect of acid rain, via pH alterations in mobilized metal effects on algal systems.