九年级科学制作生态球内容摘要:
生态系统的稳定性已被破坏。 这时应把从开始观察到停止观察所经历的天数记录下来。 • 比较小生态瓶中生态系统稳定性时间的长短,并分析出现差异的原因。 若试管内多增加一些生产者,减少一些消费者,能否使生态系统保持稳定的时间更长些。 • 若试管内多增加一些生产者,减少一些消费者,并不能使生态系统较长时间地保持稳定,因为消费者呼吸作用释放的二氧化碳是光合作用的原料,增加生产者、减少消费者会使该生态系统中的物质循环失衡。 如何能使生态系统保持稳定的时间更长些。 • 要使生态球持续稳定的时间更长一些,一。九年级科学制作生态球
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