In megacities water quantity and quality are threatened by complex and interrelated processes caused by population growth, land use change, unsustainable agricultural practices, deforestation, erosion, destruction of ecosystems, lack of planning, laissez-faire policies, unsustainable water management, political conflicts, and increasingly also by the impacts of climate change.

Ecosystem services are a powerful tool for land-use and environmental planning, which can help decision makers better understand the tradeoffs between different development scenarios. However, there is limited guidance about how ecosystem services should be used in the land-use and environmental planning context.

Heat island is the main product of urban climate, and one of the important problems of twenty-first century. Cities in tropical countries suffer extensively due to the urban heat island effect, and urban climate studies are necessary to improve the comfort level and city planning. Chennai is the tropical city; it is the fourth largest metropolis in India and one of the fastest growing economic and industrial growth centers in South Asia.

Countries around the world have responded to the problems associated with rapid urban growth and increasingly land-consumptive development patterns by creating a wide range of policy instruments designed to manage urban growth. Of the array of growth management techniques, urban containment policies are considered by some to be a promising approach. This paper focuses on greenbelts, the most restrictive form of urban containment policy. The long-standing greenbelt of Seoul, Republic of Korea is examined as a case study.

Good urban riverfronts have both ecological and social benefits in urban planning and development. With rapid increase of urban stream rehabilitation projects in developing countries, the concept of Public Accessibility of Riverfront (PAR) has become a highlight in evaluating river ecosystem improvement. In this study the Comprehensive Index of Public Accessibility of Riverfront (CIPAR) that consists of 4 sub-indexes and 12 indicators is designed for assessing the conditions of PAR. The index system is novel for its combined consideration of riverfront accessibilities and benefits.

Urban areas are the most dynamic region on earth. Their size has been constantly increased during the past and this process will go on in the future. Since there is no standard policy and guidelines for construction of buildings and urban planning, cities tend to have irregular growth. Many cities in the world face the problem of urban sprawl in its suburbs. So issues of urban sprawl need to be settled with the help of technologies such as satellite remote sensing and automated change detection.

Urban habitats, particularly wastelands and brownfields, maintain rich biodiversity and offer habitat for many species, even rare and endangered taxa. However, such habitats are also under socio-economic pressures due to redevelopment for housing and industrial uses. In order to maintain urban biodiversity, it is currently unknown how much open area must be preserved and whether conservation is possible without complete exclusion from economic development.

The ecological footprint (EF) and its unit, the global hectare, share a reputation of effectively communicating the connection between local awareness and global impact. One use of a Geographic Information System (GIS) in urban planning is decision support, while the potential of the ecological footprint in GIS has not developed significantly. The smaller the spatial unit in GIS, the more accurate and flexible are the available GIS analyses.

Determining the performance of ecosystem services at the city or regional level cannot accurately take into account the fine differences between green or gray structures. The supply of regulating ecosystem services in, for instance, parks can differ as parks vary in their land cover composition. A comprehensive ecosystem service assessment approach also needs to reflect land use to consider the demands placed on ecosystem services, which are mostly neglected by current research yet important for urban planning.

Land use change models are powerful tools that allow planners and policy makers to assess the long-term spatial and environmental impacts of their decisions. In order for these models to produce a realistic output, they should be properly calibrated. This is usually achieved by comparing simulated land-use maps of dates in the past to reference land-use maps of a corresponding date. As land-use data are often not readily or frequently available, we propose a two-stage calibration framework that includes existing land-use maps as well as remote sensing derived maps of the urban extent.

Scientific interpretation of the relationships between urban landscape patterns and water quality is important for sustainable urban planning and watershed environmental protection.