The Urban environment has a dramatic effect on local resources and on the natural environment: Large concentration of humans and their activities in a relatively small area typically cause increase in local pollution, decrease in natural habitat and more. Beyond these obvious and observable effects, urban centers also act as “heat sinks” or “hotspots” due to the tendency of materials such as concrete and asphalt to absorb heat. This creates micro-climates that induce more energy use (A/C), increasing the use of non-renewable energy and increasing air pollution.
In recent years, following a growing awareness of the complex and accumulative effects of urban centers, many local and national governments have put into practice policies, regulations and recommendation. These are designed to promote the implementation of a wide array of practices for the conservation, purification, and protection of water resources and energy conservation, and to increase the quality of life of city-dwellers:
- Water harvesting and storm-water buffering are now standard practices in many modern developments as water management measures, reducing the loads on collection systems and providing re-charge of groundwater.
- There is a growing trend of increasing green spaces within urban centers for recreational and aesthetic purposes as well as air purification, storm-water buffering and carbon sequestration. This trend has translated into national and international recommendations and standards: the World Health Organization (WHO) suggests ensuring at least a minimum availability of 9m2 green open space per city dweller, while a standard of 40m² urban green spaces and up to 140m² per capita in high quality suburbs has been suggested and in some cases implemented by experts around the world, mainly in Europe, North America and few developing countries.
These trends are indeed a positive step towards a more balances environment. However, they do not address the main issues the cities face such as heat accumulation, wastewater collection, purification and re-use.
An integral part of modern urban planning and construction, urban landscaping, provides an array of functions for the residents and visitors in the form of urban parks, gardens, boulevards etc. These serve as recreational and aesthetic sites, help to define and differentiate between functional zones, are used for commemoration of events or figures, and generally create a healthy environment. However, with the proper planning, Urban Landscaping can turn into active tools that can also provide valuable ecosystem services to buffer the harmful effects of the urban environment and in the long run offer substantial reduction in some operational costs associated with the continuous operation and improvement of the city infrastructure.
Some of the services active green spaces can offer:
- “Green Lungs”- removal of atmospheric pollutants
- “Green kidneys” – for wastewater treatment and recycling
- Mitigation of urban heat island effects
- Microclimate regulation
- Groundwater recharge
- Conservation of biodiversity
- Oxygen generation
- Noise reduction
- Reduction of fresh water consumption
- Prevention of soil erosion
- Carbon sequestration
- Life quality for generations to come
Natural Biological Systems (NBS), a practical, economic and sustainable treatment system for water, soil and air offers sustainable, on-site solutions for integrating purification zones into densely populated urban centers and creation of Active Parks, reducing the need for complex infrastructure and expensive O&M.
Developed by the Israel-based Ayala Water & Ecology, the NBS is a modular and sophisticated tool based on the science of Phyto-technology, and enhanced by modern engineering. The NBS makes use of local biotic and a-biotic components such as
- Varying Hydrology methods
- Plant database to match micro-organisms needed to dismantle pollutant sources
- Variety of aggregates, differing physically and chemically
Together, the biological, physiological and chemical elements degrade, accumulate, extract, and volatilize contaminants of all kinds and offer a complete solution for a wide range of applications: Agricultural wastewater, Industrial wastewater, Landfill leachate, Sanitary & Urban Sewage, River and Lake Rehabilitation and more.
The NBSs are constructed using local material and labor and require little and simple maintenance and typically very little energy, if any.