Biodiversity of a city depends largely on its geographical position. Pune city is situated in the transition zone between the Deccan plateau and moist mountains, the Western Ghats. 'Pune Urban Area' measuring about 700 km² , has radius of about 25 km from the city post office. It consists of Pune and Pimpri-Chinchwad Municipal Corporations besides cantonments at Pune, Khadki and Dehu Road. It also includes adjoining semi-urban areas. Biodiversity in Pune is characterised by:
* Higher habitat diversity within a relatively smaller area.
* Steep habitat gradient - Habitats change rapidly within short distances in towns and cities. Pune urban area has seven habitats within a distance of 25 km from the centre of the city. These habitats are: built-up area, rivers and lakes, well wooded compounds, hilltops and hill slopes’ parks and gardens, open places – grounds and shoulders of the roads and urban agriculture.
* Rapid changes in habitat and land use - new residential colonies are getting built on the agricultural land or grassland and scrubland. Old wadas (mansions) are rapidly getting replaced with tall residential – cum – commercial complexes, water bodies are reclaimed, filled to create land for construction. New water pools come up in city parks and gardens. All these changes have taken place within a very short period of time.
* Abundant food supply - Large garbage dumping grounds and local garbage dumps in urban areas provide a diversity of food to scavenger animals such as smaller cats, dogs, etc. Scavenger birds such as crow, myna, kite, etc. also abound in such dumps.
* Higher proportion of exotic flora - City parks, gardens and compounds are always planted with ornamental plants and trees of exotic nature. In many city gardens more than half of the trees are exotic. Many hedge plants in urban areas are not native. For many decades a variety of exotic trees such as Eucalyptus, Glyricidia, and Australian acacia has been widely used for plantation. Many plants in terrace gardens are also exotic. Urban flora therefore is a mixture of native and exotic species.