Rapid population growth and economic development are accompanied by the consumption of huge amounts of resources.

The resources consumed during human activities are enormous, which leads to the depletion of resources on the earth.

A typical example is the shortage of water resources.

As global warming gets worse day by day, a severe drought has hit different countries, causing the water levels of reservoirs to keep falling and groundwater to run dry.

In Attica of Greece the water levels of major reservoirs have recently decreased rapidly, reducing the total water storage from 597 million cubic metres last year to 377 million cubic metres. In the future, cities will suffer from extreme water shortages if it rains no longer.

In several countries, which are suffering from extreme water shortages, groundwater is pumped at random to be used as domestic water, with the result that the water of natural aquifers is rapidly decreasing. Therefore, many cities have faced the danger of ground subsidence.

And the deposits of fossil raw materials and various minerals, which constituted the driving force of industrialization, continues to decrease.

The reality requires that all resources be saved and used effectively.

Now many countries pay attention to the issue with the point of view that “saving one thing is equivalent to obtaining two things”.

Measures are being taken to make effective use of water, electricity and materials.

Shortly ago, the Iranian government called for effectively managing water resources in the capital city to cope with the five-year-long severe drought, finding out additional water resources and conducting a mass campaign for saving water.

A country sees to it that only half of the street lamps on expressways are lit at night.

Another country is promoting the adoption of a law aimed at reducing energy consumption by 10% in two years. One of the requirements of the law is to save electricity used for the operation of air-conditioners.

Recycling well under way worldwide can be said to reflect the present trend of saving resources and protecting the environment.

The waste materials and rubbish from production activities and people’s life include very many recyclable things. If they are recycled, it will be effective in saving resources and preventing environmental destruction.

For example, a huge number of electronic products such as mobile phone and computer are discarded in a year. Recycling them gives various kinds of nonferrous metals and plastics. According to data, retrieving gold from one ton of abandoned electronic circuits is much more economical than extracting gold from one ton of gold ore.

Many countries have enacted various laws for waste disposal and recycling and enforce them under strict government supervision.

Waste that is not recyclable is converted into energy at waste incineration plants.

A country uses the heat and gas from the incineration of waste to provide heating and generate electricity.

Like this, the proper disposal of household rubbish and other waste materials makes it possible to save energy a lot.

Better development can be achieved when even a single thing is used more effectively and saved.