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  • General

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  • 食物链链

    A grasshopper resting on green grass blades, illustrating a food chain interaction.

    How do the grasshopper and the grass interact?
    ::和草的相互作用如何?

    Grasshoppers don't just hop on the grass. They also eat the grass. Other organisms also eat the grass, and some animals even eat the grasshopper. These interactions can be visualized by drawing a food web .
    ::不只是跳上草地,它们也吃草。其他生物也吃草,有些动物甚至吃。这些相互作用可以通过绘制食物网来想象。

    Food Webs
    ::食品网

    Energy must constantly flow through an for the system to remain stable. What exactly does this mean? Essentially, it means that organisms must eat other organisms. Food chains ( Figure ) show the eating patterns in an ecosystem. Food energy flows from one organism to another. Arrows are used to show the feeding relationship between the animals. The arrow points from the organism being eaten to the organism that eats it. For example, an arrow from a plant to a grasshopper shows that the grasshopper eats the leaves. Energy and nutrients are moving from the plant to the grasshopper. Next, a might prey on the grasshopper, a snake may eat the bird, and then an owl might eat the snake. The food chain would be:
    ::能量必须不断流经一个系统才能保持稳定。 这到底意味着什么? 基本上,它意味着生物必须吃其他生物。 食物链(图)显示生态系统的饮食模式。 食物能量从一个有机体流向另一个有机体。 箭头用来显示动物之间的喂食关系。 从有机体到食用它的有机体的箭点。 例如, 箭头从一个植物射向一个草坪, 表明吃叶子。 能量和营养素正在从植物移向蝗虫。 下一步, 一只蛇可能会捕食蝗虫, 一只蛇可能会吃掉鸟, 然后一只猫可能会吃掉蛇。 食物链是:

    plant → grasshopper → bird → snake → owl.

    A food chain cannot continue to go on and on. For example the food chain could not be:
    ::食物链不能继续延续下去。 例如,食物链不能是:

    plant → grasshopper → spider → frog → lizard → fox → hawk.

    Food chains only have 4 or 5 total levels. Therefore, a chain has only 3 or 4 levels for energy transfer.
    ::食物链只有4或5个总水平,因此,一个链只有3或4个水平的能源转移。

    A food chain showing an owl, snake, bird, grasshopper, and plant.
    This food chain includes producers and consumers. How could you add decomposers to the food chain?

    In an ocean ecosystem, one possible food chain might look like this: phytoplankton → krill → → shark. The are always at the beginning of the food chain, bringing energy into the ecosystem. Through , the producers create their own food in the form of glucose , but also create the food for the other organisms in the ecosystem. The herbivores come next, then the carnivores . When these consumers eat other organisms, they use the glucose in those organisms for energy. In this example, phytoplankton are eaten by krill, which are tiny, shrimp-like animals. The krill are eaten by fish, which are then eaten by sharks. Could decomposers be added to a food chain?
    ::在海洋生态系统中,一个可能的食品链可能看起来是这样的: 浮游植物 鲨鱼。 浮游植物总是在食物链的起点, 将能量带入生态系统。 通过它, 生产者以葡萄糖的形式创造了自己的食物, 但也为生态系统中的其他生物创造了食物。 食草动物接下来是食肉动物。 当这些消费者食用其他生物时, 他们用这些生物中的葡萄糖作为能量。 例如, 浮游植物被虾吃掉, 虾类动物非常小。 磷虾被鱼吃掉, 然后被鲨鱼吃掉。 脱腐动物可以加入食物链吗 ?

    Each organism can eat and be eaten by many different types of organisms, so simple food chains are rare in nature. There are also many different species of fish and sharks. So a food chain cannot end with a shark; it must end with a distinct species of shark. A food chain does not contain the general category of "fish," it will contain specific species of fish. In ecosystems, there are many food chains.
    ::每个生物体都可以吃和被许多不同类型的生物吃,因此简单的食物链在性质上是罕见的。还有许多不同的鱼类和鲨鱼种类。因此,食物链不能以鲨鱼结束;它必须以不同的鲨鱼种类结束。食物链不包含“鱼类”的一般类别,它包含特定的鱼类种类。在生态系统中,有许多食物链。

    Since feeding relationships are so complicated, we can combine food chains together to create a more accurate flow of energy within an ecosystem. A food web ( Figure ) shows the feeding relationships between many organisms in an ecosystem. If you expand our original example of a food chain, you could add deer that eat clover and foxes that hunt chipmunks. A food web shows many more arrows, but still shows the flow of energy. A complete food web may show hundreds of different feeding relationships.
    ::由于喂养关系如此复杂,我们可以将食物链结合起来,在生态系统内创造更准确的能源流动。一个食物网(图 ) 显示了生态系统中许多生物之间的喂养关系。如果你扩大我们最初的食物链例子,你可以增加鹿吃花栗鼠猎杀的花栗鼠和狐狸。一个食物网可以显示更多的箭头,但仍显示能量流动。一个完整的食物网可以显示数百种不同的喂养关系。

    For more information on food chains, see A Million Sharks at  .
    ::有关食物链的更多信息,请见《百万鲨鱼》。

    A food web diagram illustrating relationships among Arctic animals and phytoplankton.
    Food web in the Arctic Ocean.

     

     

    Summary
    ::摘要

    • A food chain is a diagram that shows feeding interactions in an ecosystem through a single pathway.
      ::食物链是一张图表,显示生态系统通过单一途径的喂养互动。
    • A food web is a diagram that shows feeding interactions between many organisms in an ecosystem through multiple intersecting pathways.
      ::食物网是一个图表,显示生态系统中许多生物之间通过多重交叉途径进行喂养的相互作用。

    Review
    ::回顾

    1. What is the difference between a food chain and a food web?
      ::食物链和食物网有什么区别?
    2. Food chains always begin with what type of organism? Why?
      ::食物链总是从哪种类型的有机体开始?为什么?
    3. What is the herbivore in the following food chain: algae →  fish →  herons?
      ::以下食物链中的食草动物是什么:藻类和鱼类?