Green City

Nature provides all these services freely everywhere without any geographical limitation and cost. None of this service may be replaced by our modern technology. The Greens / Vegetables are the main elements of terrestrial biophysical, performing most of these services, either as a single item or combined with other biophysical variables, directly or indirectly

Role of the city green The integrated components of human and biophysical variables (environment) of the city is commonly known as the urban ecosystem. The relations between these four components are highly complex and always in conflict with each other. The cities are expanding in size at the expense of the nature (biophysical variables). The city green (trees, lawns / parks, forests and farmland, etc), biophysical elements is only possible to keep our city (as the man changed all the other elements in the city are irreparable) that can provide basic services for human survival. According to the American Forestry Association (AFA) a tree in the city can provide a value of more air conditioning, erosion, stormwater control, wildlife refuges and control of air pollution over 50 years of life
How to Build a Green City Before answering this question, consider how important it is for cities to begin to be green, and new cities (yes, we will need new cities) for green building. Today's cities consume 75% of global energy produced & are responsible for 80% of carbon emissions. Last year, according to four estimate, the population of the world at the tip so that for the first time in human history more live in cities than in rural areas - & the world's urban population is expected to grow so quick that they must build the equivalent of a city of four million people every four days. WWF plans to help Foster and Associates design the new city of 50,000 people in less than four square miles by exceeding the One Planet Living program guidelines, which WWF helped design as a global benchmark for sustainable urban development. Among the highlights:
1. Zero carbon. All electricity for the city will come from photovoltaic solar panels. Air conditioning will be produced by concentrated solar energy. Other energy need will be met by wind energy or waste in energy technology .
2. Less water waste. The water will be produced by a desalination plant with solar energy, & both treated sewage & "gray water" from sinks & taps to be used to irrigate crops outside the city limits.
3. Better food. Restaurants and grocery stores are retail trade forced to sell organic foods, sustainable and fair .