Humans and nature
Like all living things, humans take oxygen and food from the environment. Long ago people lived on fruits, seeds and hunting, then began using fire, took up farming and herding, and settled in one place. Humans have positive effects on nature: they create new plant varieties and new animal breeds (meat, milk), plant trees and protect nature. The negative effects are also large: excessive hunting of wild animals, cutting forests, and polluting air and water with waste. As a result environmental problems appear. For example, the Aral Sea dried up sharply because a large part of the water of the Amu Darya and Syr Darya was taken for irrigation. Burning fuel adds carbon dioxide, the air warms and glaciers melt. Certain gases from old refrigerators and aerosols thinned the ozone layer; the ozone layer shields the Earth from the Sun’s harmful rays, and if more of those rays arrive they harm skin and eyes. Under an international agreement restricting these gases, the ozone layer is now slowly recovering. Biological knowledge helps reduce the negative effects: saving water, planting trees, sorting waste and not littering, saving electricity.
Choose one environmental problem near your home or school (for example litter in a canal, felled trees) and make a “problem – cause – solution” card. Then write a “Three steps for nature” plan for your family (saving water, sorting waste, caring for a tree). Safety: when collecting litter outdoors wear gloves, do not touch glass or sharp items, and work with adults.