题干

生态系统物质循环的特点不包括下列的(   )

A:带有全球性

B:在生态系统的各营养级之间循环往复

C:物质是指组成生物体的基本元素

D:在群落与无机环境之间循环往复

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答案(点此获取答案解析)

B

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    Would it surprise you to learn that, like animals, trees communicate with each other and pass on their wealth to the next generation?

    UBC Professor Simard explains how trees are much more complex than most of us ever imagined.

    Although Charles Darwin thought that trees are competing for survival of the fittest, Simard shows just how wrong he was. In fact, the opposite is true: trees survive through their co-operation and support, passing around necessary nutrition “depending on who needs it”.

    Nitrogen (氮) and carbon are shared through miles of underground fungi (真菌) networks, making sure that all trees in the forest ecological system give and receive just the right amount to keep them all healthy. This hidden system works in a very similar way to the networks of neurons (神经元) in our brains, and when one tree is destroyed, it affects all.

    Simard talks about “mother trees”, usually the largest and oldest plants on which all other trees depend. She explains how dying trees pass on the wealth to the next generation, transporting important minerals to young trees so they may continue to grow. When humans cut down “mother trees” with no awareness of these highly complex “tree societies” or the networks on which they feed, we are reducing the chances of survival for the entire forest.

     “We didn't take any notice of it,” Simard says sadly. “Dying trees move nutrition into the young trees before dying, but we never give them chance.” If we could put across the message to the forestry industry, we could make a huge difference towards our environmental protection efforts for the future.