Green space indicators in a social-ecological system: A case study of Varanasi, India

From an ecological perspective, quantification indicators of urban green space distribution and accessibility have been the focus of only a few studies. To determine the thresholds of various urban drivers influencing the extent of green spaces was the major objective of this study. We selected Varanasi, a typical city having transition features of a rapidly growing million-plus city, as a model using a multivariate approach. The ward level differences with literates, workers, population density, household density, per-capita green space, open spaces, built area and green spaces were found to be non-linearly distributed. Indicators for green spaces were identified using the Generalized Additive Model (GAM). Varanasi showed a variation of per capita green-spaces from 0 to 59.95 m(2) at the ward level. Green-spaces showed a large negative correlation with population density (tau = -0.5), household density (tau = -0.5) and built area (tau = -0.7). Sustainability thresholds for built land use and open spaces were identified as 49-76 % and 5.6 %, respectively. Provision of greenspaces even in very small amounts and education based on a local environmental perspective is essential in creating a sustainable urban landscape. The threshold values of identified indicators can help in devising a safe operating space for sustainable and healthy urban landscape planning, worldwide.