NCERT Solutions for Class 7 Science Chapter 12 Forests Our Lifeline

Various types of animals (herbivores, carnivores, omnivores) live in forests and contribute to food chain. Following activities show how animals help forest grow and regenerate. Animals help in dispersal of seeds from one part of the forest to other part. Animal’s excreta and their dead bodies when decomposed into soil act as manure for the plants. Microorganisms convert dead plants and leaves into humus which is rich in nutrients. Humus in soil provide necessary minerals for plant growth.

The micro-organisms which convert the dead plants and animals to humus are known as decomposers. Examples: Fungi and Bacteria. Decomposers recycle and convert the dead matter into humus which mixes with forest soil and provide necessary nutrients to plants. Thus decomposers help in maintaining the necessary nutrient balance in the soil.

Forests play an important role in maintaining the balance between oxygen and carbon dioxide in the atmosphere. Forest works like a self-sustaining system. Whatever is produced in the forest is utilized by different components of the forest. Animals during respiration take in oxygen and release carbon dioxide. Plants take in carbon dioxide and release oxygen through the process of photosynthesis. Even the waste is converted into beneficial substances in a forest. Due to this, there is no waste in a forest.

The insects, butterflies, honeybees and birds help flowering plants in pollination.

Forests are very important resources. We should be careful and concerned about the issues related to forest due to following reasons: If there are no forests, there would be more floods and more soil erosion. Forests affect the global environment in a great way. For example; reduced forest cover in a particular area leads to global warming which affects the whole earth. Forests are the dwelling of many animals. Deforestation will endanger our life and environment. In the absence of trees and plants, the animals will not get food and shelter. Forests provide us large number of useful products including wood, fruits and medicines. These products would not be available in the absence of trees and plants.