The “Miyawaki method” is well known for the:

The correct option is "Creation of mini forests in urban areas".

Explanation:
The Miyawaki method is an afforestation technique pioneered by the Japanese botanist Akira Miyawaki in the 1970s. It involves planting various native species of plants close together in a multi-layered manner, which encourages rapid growth and helps create dense, self-sustaining micro-forests in a relatively short period (typically 20 to 30 years, compared to 100 to 200 years for traditional forests).

This method has become highly popular globally for urban greening because it allows for the rapid creation of mini forests in degraded or confined urban spaces. These mini forests help lower local temperatures, reduce air and noise pollution, support local biodiversity, and improve groundwater absorption, making it a key tool for ecological restoration in cities.