食物链中毒素的累积

解释生物如何影响其环境并受环境影响，包括有毒物质（如农药、重金属）通过食物链产生的生物累积。

Explain how organisms affect and are affected by their environment, including the bioaccumulation of toxic materials (e.g. pesticides, heavy metals) through food chains

学习证据 / Evidence

• 定义生物累积，并解释为什么毒素在食物链越往上层浓度越高
• 举出生物累积的真实例子（如DDT在游隼体内累积、汞在金枪鱼体内累积）
• 解释生物如何改变其栖息地（如蚯蚓松土、河狸创造湿地）
• 论述为什么顶级捕食者受生物累积危害的风险最大

• Defines bioaccumulation and explains why toxins increase in concentration higher up the food chain
• Gives a real example of bioaccumulation (e.g. DDT in peregrine falcons, mercury in tuna)
• Explains how organisms can change their habitat (e.g. earthworms aerating soil, beavers creating wetlands)
• Discusses why top predators are most at risk from bioaccumulation

评估问题 / Assessment

如果{{name}}听说金枪鱼等大型鱼类体内含汞量可能比小鱼更高，他们能否解释原因——即便金枪鱼并未直接接触汞？

If {{name}} heard that large fish like tuna can contain more mercury than small fish, could they explain why that is — even though the tuna didn’t encounter mercury directly?