Carbon is available to crop plants in the form of

The amount of usable energy, which is available for doing work, when the temperature and pressure are uniform throughout the system is called

Another name of nutrient cycling is

Apart from plants and animals, microbes form a permanent biotic component in an ecosystem. While plants have been referred to as autotrophs and animals as heterotrophs, what are microbes referred to as ? How do the microbes fulfil their energy requirements ?

Which of the following ecosystems will be more productive in terms of primary productivity ? Justify your answer. A young forest, a natural old forest, a shallow polluted lake, alpine meadow.