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Friday, June 14, 2019

New Urbanism

From Wikipedia, the free encyclopedia

New Urbanism is an urban design movement which promotes environmentally friendly habits by creating walkable neighborhoods containing a wide range of housing and job types. It arose in the United States in the early 1980s, and has gradually influenced many aspects of real estate development, urban planning, and municipal land-use strategies. 

New Urbanism is strongly influenced by urban design practices that were prominent until the rise of the automobile prior to World War II; it encompasses ten basic principles such as traditional neighborhood design (TND) and transit-oriented development (TOD). These ideas can all be circled back to two concepts: building a sense of community and the development of ecological practices.

Market Street, Celebration, Florida
 
The organizing body for New Urbanism is the Congress for the New Urbanism, founded in 1993. Its foundational text is the Charter of the New Urbanism, which begins:
We advocate the restructuring of public policy and development practices to support the following principles: neighborhoods should be diverse in use and population; communities should be designed for the pedestrian and transit as well as the car; cities and towns should be shaped by physically defined and universally accessible public spaces and community institutions; urban places should be framed by architecture and landscape design that celebrate local history, climate, ecology, and building practice.
New Urbanists support: regional planning for open space; context-appropriate architecture and planning; adequate provision of infrastructure such as sporting facilities, libraries and community centres;[5] and the balanced development of jobs and housing. They believe their strategies can reduce traffic congestion by encouraging the population to ride bikes, walk, or take the train. They also hope that this set up will increase the supply of affordable housing and rein in suburban sprawl. The Charter of the New Urbanism also covers issues such as historic preservation, safe streets, green building, and the re-development of brownfield land. The ten Principles of Intelligent Urbanism also phrase guidelines for new urbanist approaches.

Architecturally, new urbanist developments are often accompanied by New Classical, postmodern, or vernacular styles, although that is not always the case.

Background

New Broad Street, Baldwin Park, Florida
 
Until the mid 20th century, cities were generally organized into and developed around mixed-use walkable neighborhoods. For most of human history this meant a city that was entirely walkable, although with the development of mass transit the reach of the city extended outward along transit lines, allowing for the growth of new pedestrian communities such as streetcar suburbs. But with the advent of cheap automobiles and favorable government policies, attention began to shift away from cities and towards ways of growth more focused on the needs of the car. Specifically, after World War II urban planning largely centered around the use of municipal zoning ordinances to segregate residential from commercial and industrial development, and focused on the construction of low-density single-family detached houses as the preferred housing format for the growing middle class. The physical separation of where people live from where they work, shop and frequently spend their recreational time, together with low housing density, which often drastically reduced population density relative to historical norms, made automobiles indispensable for practical transportation and contributed to the emergence of a culture of automobile dependency

 
This new system of development, with its rigorous separation of uses, arose after World War II and became known as "conventional suburban development" or pejoratively as urban sprawl. The majority of U.S. citizens now live in suburban communities built in the last fifty years, and automobile use per capita has soared.

Celebration, FL Post Office, designed by architect Michael Graves
 
Although New Urbanism as an organized movement would only arise later, a number of activists and thinkers soon began to criticize the modernist planning techniques being put into practice. Social philosopher and historian Lewis Mumford criticized the "anti-urban" development of post-war America. The Death and Life of Great American Cities, written by Jane Jacobs in the early 1960s, called for planners to reconsider the single-use housing projects, large car-dependent thoroughfares, and segregated commercial centers that had become the "norm". The French architect François Spoerry has developed in the 60's the concept of "soft architecture" that he applied to Port Grimaud, a new marina in south of France. The success of this project had a considerable influence and led to many new projects of soft architecture like Port Liberté in New Jersey or Le Plessis Robisson in France.

Rooted in these early dissenters, the ideas behind New Urbanism began to solidify in the 1970s and 80s with the urban visions and theoretical models for the reconstruction of the "European" city proposed by architect Leon Krier, and the pattern language theories of Christopher Alexander. The term "new urbanism" itself started being used in this context in the mid-1980s, but it wasn't until the early 1990s that it was commonly written as a proper noun capitalized.

In 1991, the Local Government Commission, a private nonprofit group in Sacramento, California, invited architects Peter Calthorpe, Michael Corbett, Andrés Duany, Elizabeth Moule, Elizabeth Plater-Zyberk, Stefanos Polyzoides, and Daniel Solomon to develop a set of community principles for land use planning. Named the Ahwahnee Principles (after Yosemite National Park's Ahwahnee Hotel), the commission presented the principles to about one hundred government officials in the fall of 1991, at its first Yosemite Conference for Local Elected Officials.

Calthorpe, Duany, Moule, Plater-Zyberk, Polyzoides, and Solomon founded the Chicago-based Congress for the New Urbanism in 1993. The CNU has grown to more than three thousand members, and is the leading international organization promoting New Urbanist design principles. It holds annual Congresses in various U.S. cities. 

In 2009, co-founders Elizabeth Moule, Hank Dittmar, and Stefanos Polyzoides authored the Canons of Sustainable Architecture and Urbanism to clarify and detail the relationship between New Urbanism and sustainability. The Canons are "a set of operating principles for human settlement that reestablish the relationship between the art of building, the making of community, and the conservation of our natural world". They promote the use of passive heating and cooling solutions, the use of locally obtained materials, and in general, a "culture of permanence".

New Urbanism is a broad movement that spans a number of different disciplines and geographic scales. And while the conventional approach to growth remains dominant, New Urbanist principles have become increasingly influential in the fields of planning, architecture, and public policy.

Defining elements

Andrés Duany and Elizabeth Plater-Zyberk, two of the founders of the Congress for the New Urbanism, observed mixed-use streetscapes with corner shops, front porches, and a diversity of well-crafted housing while living in one of the Victorian neighborhoods of New Haven, Connecticut. They and their colleagues observed patterns including the following:

 
Great King St, New Town, Edinburgh
  • The neighborhood has a discernible center. This is often a square or a green and sometimes a busy or memorable street corner. A transit stop would be located at this center.
  • Most of the dwellings are within a five-minute walk of the center, an average of roughly 0.25 miles (0.40 km).
  • There are a variety of dwelling types — usually houses, rowhouses, and apartments — so that younger and older people, singles and families, the poor and the wealthy may find places to live.
  • At the edge of the neighborhood, there are shops and offices of sufficiently varied types to supply the weekly needs of a household.
  • A small ancillary building or garage apartment is permitted within the backyard of each house. It may be used as a rental unit or place to work (for example, an office or craft workshop).
  • An elementary school is close enough so that most children can walk from their home.
  • There are small playgrounds accessible to every dwelling — not more than a tenth of a mile away.
  • Streets within the neighborhood form a connected network, which disperses traffic by providing a variety of pedestrian and vehicular routes to any destination.
  • The streets are relatively narrow and shaded by rows of trees. This slows traffic, creating an environment suitable for pedestrians and bicycles.
  • Buildings in the neighborhood center are placed close to the street, creating a well-defined outdoor room.
  • Parking lots and garage doors rarely front the street. Parking is relegated to the rear of buildings, usually accessed by alleys.
  • Certain prominent sites at the termination of street vistas or in the neighborhood center are reserved for civic buildings. These provide sites for community meetings, education, and religious or cultural activities.

Terminology

Several terms are viewed either as synonymous, included in, or overlapping with the New Urbanism. The terms Neotraditional Development or Traditional Neighborhood Development are often associated with the New Urbanism. These terms generally refer to complete New Towns or new neighborhoods, often built in traditional architectural styles, as opposed to smaller infill and redevelopment projects. The term Traditional Urbanism has also been used to describe the New Urbanism by those who object to the "new" moniker. The term "Walkable Urbanism" was proposed as an alternative term by developer and professor Christopher Leinberger. Many debate whether Smart Growth and the New Urbanism are the same or whether substantive differences exist between the two; overlap exists in membership and content between the two movements. Placemaking is another term that is often used to signify New Urbanist efforts or those of like-minded groups. The term Transit-Oriented Development is sometimes cited as being coined by prominent New Urbanist Peter Calthorpe and is heavily promoted by New Urbanists. The term Sustainable development is sometimes associated with the New Urbanism as there has been an increasing focus on the environmental benefits of New Urbanism associated with the rise of the term sustainability in the 2000s, however, this has caused some confusion as the term is also used by the United Nations and Agenda 21 to include human development issues (e.g., developing country) that exceed the scope of land development intended to be addressed by the New Urbanism or Sustainable Urbanism. The term "livability" or "livable communities" was popular under the Obama administration, though it dates back at least to the mid-1990s when the term was used by the Local Government Commission.

 
Planning magazine discussed the proliferation of "urbanisms" in an article in 2011 titled "A Short Guide to 60 of the Newest Urbanisms". Several New Urbanists have popularized terminology under the umbrella of the New Urbanism including Sustainable Urbanism and Tactical Urbanism (of which Guerrilla Urbanism can be viewed as a subset). The term Tactical Urbanism was coined by Frenchman Michel de Certau in 1968 and revived in 2011 by New Urbanist Mike Lydon and the co-authors of the Tactical Urbanism Guide. In 2011 Andres Duany authored a book that used the term Agrarian Urbanism to describe an agriculturally-focused subset of New Urbanist town design. In 2013 a group of New Urbanists led by CNU co-founder Andres Duany began a research project under the banner of Lean Urbanism which purported to provide a bridge between Tactical Urbanism and the New Urbanism. 

Other terms have surfaced in reaction to the New Urbanism intended to provide a contrast, alternative to, or a refinement of the New Urbanism. Some of these terms include Everyday Urbanism by Harvard Professor Margaret Crawford, John Chase, and John Kaliski, Ecological Urbanism, and True Urbanism by architect Bernard Zyscovich. Landscape urbanism was popularized by Charles Waldheim who explicitly defined it as in opposition to the New Urbanism in his lectures at Harvard University. Landscape Urbanism and its Discontents, edited by Andres Duany and Emily Talen, specifically addressed the tension between these two views of urbanism. Michael E. Arth promotes what he describes as a variant of the New Urbanism called the New Pedestrianism, which is intended to be more pedestrian-oriented and traces its origins to a 1929 planned community in Radburn, New Jersey.

Organizations

New urbanist Sankt Eriksområdet quarter in Stockholm, Sweden, built in the 1990s.
 
The primary organization promoting the New Urbanism in the United States is the Congress for the New Urbanism (CNU). The Congress for the New Urbanism is the leading organization promoting walkable, mixed-use neighborhood development, sustainable communities and healthier living conditions. CNU members promote the principles of CNU's Charter and the hallmarks of New Urbanism, including:
  • Livable streets arranged in compact, walkable blocks.
  • A range of housing choices to serve people of diverse ages and income levels.
  • Schools, stores and other nearby destinations reachable by walking, bicycling or transit service.
  • An affirming, human-scaled public realm where appropriately designed buildings define and enliven streets and other public spaces.
The CNU has met annually since 1993 when they held their first general meeting in Alexandria, Virginia, with approximately one hundred attendees. By 2008 the Congress was drawing two to three thousand attendees to the annual meetings. 

The CNU began forming local and regional chapters circa 2004 with the founding of the New England and Florida Chapters. By 2011 there were 16 official chapters and interest groups for 7 more. As of 2013, Canada hosts two full CNU Chapters, one in Ontario (CNU Ontario), and one in British Columbia (Cascadia) which also includes a portion of the north-west US states. 

While the CNU has international participation in Canada, sister organizations have been formed in other areas of the world including the Council for European Urbanism (CEU), the Movement for Israeli Urbanism (MIU) and the Australian Council for the New Urbanism. 

By 2002 chapters of Students for the New Urbanism began appearing at universities including the Savannah College of Art and Design, University of Georgia, University of Notre Dame, and the University of Miami. In 2003, a group of younger professionals and students met at the 11th Congress in Washington, D.C. and began developing a "Manifesto of the Next Generation of New Urbanists". The Next Generation of New Urbanists held their first major session the following year at the 12th meeting of the CNU in Chicago in 2004. The group has continued meeting annually as of 2014 with a focus on young professionals, students, new member issues, and ensuring the flow of fresh ideas and diverse viewpoints within the New Urbanism and the CNU. Spinoff projects of the Next Generation of the New Urbanists include the Living Urbanism publication first published in 2008 and the first Tactical Urbanism Guide.

The CNU has spawned publications and research groups. Publications include the New Urban News and the New Town Paper. Research groups have formed independent nonprofits to research individual topics such as the Form-Based Codes Institute, The National Charrette Institute and the Center for Applied Transect Studies.

In the United Kingdom New Urbanist and European urbanism principles are practised and taught by The Prince's Foundation for the Built Environment

Around the world, other organisations promote New Urbanism as part of their remit, such as INTBAU, A Vision of Europe, Council for European Urbanism, and others. 

The CNU and other national organizations have also formed partnerships with like-minded groups. Organizations under the banner of Smart Growth also often work with the Congress for the New Urbanism. In addition the CNU has formed partnerships on specific projects such as working with the United States Green Building Council and the Natural Resources Defense Council to develop the LEED for Neighborhood Development standards, and with the Institute of Transportation Engineers to develop a Context Sensitive Solutions (CSS) Design manual.

Film

The New Urbanism Film Festival was held in 2013 and 2014 in Los Angeles to highlight films and short films about the New Urbanism and related topics. The 2011 film Urbanized by Gary Hustwit featured then CNU Board Chair Ellen Dunham-Jones and other urban thinkers on the international story of urbanization including the New Urbanist efforts in the United States. 

The 2004 documentary The End of Suburbia: Oil Depletion and the Collapse of the American Dream argues that the depletion of oil will result in the demise of the sprawl-type development. New Urban Cowboy: Toward a New Pedestrianism, a feature length 2008 documentary about urban designer Michael E. Arth, explains the principles of his New Pedestrianism, a more ecological and pedestrian-oriented version of New Urbanism. The film also gives a brief history of New Urbanism, and chronicles the rebuilding of an inner city slum into a model of New Pedestrianism and New Urbanism called The Garden District.

Criticism

New Urbanism has drawn both praise and criticism from all parts of the political spectrum. It has been criticized both for being a social engineering scheme and for failing to address social equity and for both restricting private enterprise and for being a deregulatory force in support of private sector developers. 

Journalist Alex Marshall has decried New Urbanism as essentially a marketing scheme that repackages conventional suburban sprawl behind a façade of nostalgic imagery and empty, aspirational slogans. In a 1996 article in Metropolis Magazine, Marshall denounced New Urbanism as "a grand fraud". The attack continued in numerous articles, including an opinion column in the Washington Post in September of the same year, and in Marshall's first book, How Cities Work: Suburbs, Sprawl, and the Roads Not Taken.

Critics have asserted that the effectiveness claimed for the New Urbanist solution of mixed income developments lacks statistical evidence. Independent studies have supported the idea of addressing poverty through mixed-income developments, but the argument that New Urbanism produces such diversity has been challenged from findings from one community in Canada.

Some parties have criticized the New Urbanism for being too accommodating of motor vehicles and not going far enough to promote walking, cycling, and public transport. The Charter of the New Urbanism states that "communities should be designed for the pedestrian and transit as well as the car". Some critics suggest that communities should exclude the car altogether in favor of car-free developments. Michael E Arth proposes new pedestrianism as a way to further elevate the status of pedestrians by focusing on pedestrian-only paths. Steve Melia proposes the idea of "filtered permeability" which increases the connectivity of the pedestrian and cycling network resulting in a time and convenience advantage over drivers while still limiting the connectivity of the vehicular network and thus maintaining the safety benefits of cul de sacs and horseshoe loops in resistance to property crime.

In response to critiques of a lack of evidence for the New Urbanism's claimed environmental benefits, a rating system for neighborhood environmental design, LEED-ND, was developed by the U.S. Green Building Council, Natural Resources Defense Council, and the Congress for the New Urbanism, to quantify the sustainability of New Urbanist neighborhood design. New Urbanist and board member of CNU, Doug Farr has taken a step further and coined Sustainable Urbanism, which combines New Urbanism and LEED-ND to create walkable, transit-served urbanism with high performance buildings and infrastructure.

Criticizing the lack of evidence for low greenhouse gas emissions results, Susan Subak has pointed out that while New Urbanism emphasizes walkability and building variety, it is the scale of dwellings, especially the absence of large houses that may determine successful, low carbon outcomes at the community level. 

New Urbanism has been criticized for being a form of centrally planned, large-scale development, "instead of allowing the initiative for construction to be taken by the final users themselves". It has been criticized for asserting universal principles of design instead of attending to local conditions.

Examples

United States

New Urbanism is having a growing influence on how and where metropolitan regions choose to grow. At least fourteen large-scale planning initiatives are based on the principles of linking transportation and land-use policies, and using the neighborhood as the fundamental building block of a region. Miami, Florida, has adopted the most ambitious New Urbanist-based zoning code reform yet undertaken by a major U.S. city.

More than six hundred new towns, villages, and neighborhoods, following New Urbanist principles, have been planned or are currently under construction in the U.S. Hundreds of new, small-scale, urban and suburban infill projects are under way to reestablish walkable streets and blocks. In Maryland and several other states, New Urbanist principles are an integral part of smart growth legislation. 

In the mid-1990s, the U.S. Department of Housing and Urban Development (HUD) adopted the principles of the New Urbanism in its multibillion-dollar program to rebuild public housing projects nationwide. New Urbanists have planned and developed hundreds of projects in infill locations. Most were driven by the private sector, but many, including HUD projects, used public money.

University Place in Memphis

In 2010 University Place in Memphis became the second only U.S. Green Building Council (USGBC) LEED certified neighborhood. LEED ND (neighborhood development) standards integrates principles of smart growth, urbanism and green building and were developed through a collaboration between USGBC, Congress for the New Urbanism, and the Natural Resources Defense Council. University Place, developed by McCormack Baron Salazar, is a 405-unit, 30-acre, mixed-income, mixed use, multigenerational, HOPE VI grant community that revitalized the severely distressed Lamar Terrace public housing site.

The Cotton District

The Cotton District in Starkville, Mississippi, was the first New Urbanist development, begun in 1968 long before the New Urbanism movement was organized. The District borders Mississippi State University, and consists mostly of residential rental units for college students along with restaurants, bars and retail. The Cotton District got its name because it is built in the vicinity of an old cotton mill.

Seaside

Seaside, Florida, the first fully New Urbanist town, began development in 1981 on eighty acres (324,000 m²) of Florida Panhandle coastline. It was featured on the cover of the Atlantic Monthly in 1988, when only a few streets were completed, and has become internationally famous for its architecture, and the quality of its streets and public spaces.

Seaside is now a tourist destination and appeared in the 1998 movie The Truman Show. Lots sold for $15,000 in the early 1980s, and slightly over a decade later, the price had escalated to about $200,000. Today, most lots sell for more than a million dollars, and some houses top $5 million.

Mueller Community

The Mueller Community is located on the 700 acre site of the former Robert Mueller Municipal Airport in Austin, Texas, which closed in 1999. Per the developer, the value of the Mueller development upon completion will be $1.3 billion, and will comprise 4.2 million square feet of non-residential development, 650,000 square feet of retail space, 4,600 homes, and 140 acres of open space. An estimated 10,000 permanent jobs within the development will have been created by the time it is complete. The Mueller Community also has more electric cars per capita than any other neighborhood in the United States – a fact partially attributable to an incentive program.

Stapleton

The site of the former Stapleton International Airport in Denver and Aurora, Colorado, closed in 1995, is now being redeveloped by Forest City Enterprises. Stapleton is expected to be home to at least 30,000 residents, six schools and 2 million square feet (180,000 m²) of retail. Construction began in 2001. Northfield Stapleton, one of the development's major retail centers, recently opened.

San Antonio

In 1997 San Antonio, Texas, as part of a new master plan, created new regulations called the Unified Development Code (UDC), largely influenced by New Urbanism. One feature of the UDC is six unique land development patterns that can be applied to certain districts: Conservation Development, Commercial Center Development, Office or Institutional Campus Development, Commercial Retrofit Development, Tradition Neighborhood Development, Transit Oriented Development. Each district has specific standards and design regulation. The six development patterns were created to reflect existing development patterns.

Mountain House

Mountain House, one of the latest New Urbanist projects in the United States, is a new town located near Tracy, California. Construction started in 2001. Mountain House will consist of 12 villages, each with its own elementary school, park, and commercial area. In addition, a future train station, transit center and bus system are planned for Mountain House.

Mesa del Sol

Mesa del Sol, New Mexico—the largest New Urbanist project in the United States—was designed by architect Peter Calthorpe, and is being developed by Forest City Enterprises. Mesa del Sol may take five decades to reach full build-out, at which time it should have 38,000 residential units, housing a population of 100,000; a 1,400-acre (5.7 km2) industrial office park; four town centers; an urban center; and a downtown that would provide a twin city within Albuquerque.

I'On

Located in Mount Pleasant, South Carolina, I'On is a traditional neighborhood development, mixed with a new urbanism styled architecture, reflecting on the building designs of the nearby downtown areas of Charleston, South Carolina. Founded on April 30, 1995, I'On was designed by the town planning firms of Dover, Kohl & Partners and Duany Plater-Zyberk & Company, and currently holds over 750 single family homes. Features of the community include extensive sidewalks, shared public greens and parks, trails and a grid of narrow, traffic calming streets. Most homes are required to have a front porch of not less than eight feet (2.46 m) in depth. Floor heights of 10 feet (3.1 m), raised foundations and smaller lot sizes give the community a dense, vertical feel.

Haile Plantation

Haile Plantation, Florida, is a 2,600 household (1,700 acres (6.9 km2)) development of regional impact southwest of the city of Gainesville, within Alachua County. Haile Village Center is a traditional neighborhood center within the development. It was originally started in 1978 and completed in 2007. In addition to the 2,600 homes the neighborhood consists of two merchant centers (one a New England narrow street village and the other a chain grocery strip mall). There are also two public elementary schools and an 18-hole golf course.

Celebration, Florida

In June 1996, the Walt Disney Company unveiled its 5,000 acre (20 km²) town of Celebration, near Orlando, Florida. Celebration opened its downtown in October 1996, relying heavily on the experiences of Seaside, whose downtown was nearly complete. Disney shuns the label New Urbanism, calling Celebration simply a "town". 

Celebration's Downtown has become one of the area's most popular tourist destinations making the community a showcase for New Urbanism as a prime example of the creation of a "sense of place".

Jersey City

The construction of the Hudson Bergen Light Rail in Hudson County, New Jersey has spurred transit-oriented development. In Jersey City, two projects are planned to transform brownfield sites, both of which have required remediation of toxic waste by previous owners. Bayfront, once site of a Honeywell plant is a 100 acres (0.40 km2) site on the Hackensack River, and is nearby the planned West Campus of New Jersey City University. Canal Crossing, named for the former Morris Canal, was once partially owned by PPG Industries, and is a 117 acres (0.47 km2) site west of Liberty State Park.

Old York Village, Chesterfield Township, New Jersey

The sparsely developed agricultural Township of Chesterfield in New Jersey covers approximately 21.61 square miles (56.0 km2) and has made farmland preservation a priority since the 1970s. Chesterfield has permanently preserved more than 7,000 acres (28 km2) of farmland through state and county programs and a township-wide transfer of development credits program that directs future growth to a designated "receiving area" known as Old York Village. Old York Village is a neo-traditional, new urbanism town on 560 acres (2.3 km2) incorporating a variety of housing types, neighborhood commercial facilities, a new elementary school, civic uses, and active and passive open space areas with preserved agricultural land surrounding the planned village. Construction began in the early 2000s and a significant percentage of the community is now complete. Old York Village was the winner of the American Planning Association National Outstanding Planning Award in 2004.

Civita

Civita is a sustainable, transit-oriented 230-acre master-planned village under development in the Mission Valley area of San Diego, California, United States. Located on a former quarry site, the urban-style village is organized around a 19-acre community park that cascades down the terraced property. Civita development plans call for 60 to 70 acres of parks and open space, 4,780 residences (including approximately 478 affordable units), an approximately 480,000-square-foot retail center, and 420,000 square feet for an office/business campus.

Sudberry Properties, the developer of Civita, incorporated numerous green building practices in the Civita design. In 2009, Civita achieved a Stage 1 Gold rating for the U.S. Green Building Council’s 2009 LEED-ND (Neighborhood Development) pilot and received the California Governor’s Environmental and Economic Leadership Award. In 2010, Civita was designated as a California Catalyst Community by the California Department of Housing and Community Development to support innovation and test sustainable strategies that reflect the interdependence of environmental, economic, and community health.

Del Mar Station

Del Mar (Los Angeles Metro station), which won a Congress for the New Urbanism Charter Award in 2003, is a transit-oriented development surrounding a prominent Metro Rail stop on the Gold Line, which connects Los Angeles and Pasadena. Located at the southern edge of downtown Pasadena, it serves as a gateway to the city with 347 apartments, out of which 15% are affordable units. Approximately 20,000 square feet of retail is linked with a network of public plazas, paseos and private courtyards. The 3.4-acre, $77 million project sits above a 1,200-car multi-level subterranean parking garage, with 600 spaces dedicated to transit. The light rail right of way, detailed as a public street, bisects the site. It was designed by Moule & Polyzoides.

Norfolk VA East Beach

Norfolk, VA, East Beach. designed and built in the style of traditional Atlantic coastal villages. The Master Plan for East Beach was developed in the style of “New Urbanism” by world renowned TND master planners Duany Plater-Zyberk. Newly constructed homes reflect traditional classic detail and proportion of Tidewater Virginia homes, and are built with materials that will withstand the test of time and forces of Mother Nature and the Chesapeake Bay.

Other countries

New Urbanism is closely related to the Urban village movement in Europe. They both occurred at similar times and share many of the same principles although urban villages has an emphasis on traditional city planning. In Europe many brown-field sites have been redeveloped since the 1980s following the models of the traditional city neighbourhoods rather than Modernist models. One well-publicized example is Poundbury in England, a suburban extension to the town of Dorchester, which was built on land owned by the Duchy of Cornwall under the overview of Prince Charles. The original masterplan was designed by Leon Krier. A report carried out after the first phase of construction found a high degree of satisfaction by residents, although the aspirations to reduce car dependency had not been successful. Rising house prices and a perceived premium have made the open market housing unaffordable for many local people.

The Council for European Urbanism (CEU), formed in 2003, shares many of the same aims as the U.S.'s New Urbanists. CEU's Charter is a development of the Congress for the New Urbanism Charter revised and reorganised to relate better to European conditions. An Australian organisation, Australian Council for New Urbanism has since 2001 run conferences and events to promote New Urbanism in that country. A New Zealand Urban Design Protocol was created by the Ministry for the Environment in 2005. 

There are many developments around the world that follow New Urbanist principles to a greater or lesser extent:

Europe

  • Le Plessis-Robinson, a 21st-century example of neo-traditionalism, in the south-west of Paris. This city is in the process of transforming itself, destroying old modern blocklike buildings and replacing them with traditional buildings and houses in one of the biggest worldwide projects with Val d'Europe. In 2008 the city was nominated best architectural project of the European Union.
  • Poundbury, in Dorset, England, is a neotraditionalist urban extension focussed on high quality urban realm and the expression of traditional modes of urban or village life.
  • Tornagrain, Between Inverness and Nairn, Scotland, The design is based on the architectural and planning traditions of the Highlands and the rest of Scotland.
  • Val d'Europe, east of Paris, France. Developed by Disneyland Resort Paris, this town is a kind of European counterpart to Walt Disney World Celebration City.
  • Jakriborg, in Southern Sweden, is a recent example of the New Urbanist movement.
  • Brandevoort, in Helmond, in the Netherlands, is a new example of the New Urbanist movement.
  • Sankt Eriksområdet quarter in Stockholm, Sweden, built in the 1990s.
  • Other developments can be found at Heulebrug, part of Knokke-Heist, in Belgium, and Fonti di Matilde in San Bartolomeo (outside of Reggio Emilia), Italy.
  • Kartanonkoski, in Vantaa, Finland, is the only example of neotraditional architecture in Finland implemented on a larger scale. The area has around 4000 inhabitants and its architecture has been mainly influenced by Nordic Classicism.

Americas

Asia

Africa

There are several such developments in South Africa. The most notable is Melrose Arch in Johannesburg. Triple Point is a comparable mixed-use development in East London, in Eastern Cape province. The development, announced in 2007, comprises 30 hectares. It is made up of three apartment complexes together with over 30 residential sites as well as 20,000 sq m of residential and office space. The development is valued at over R2 billion ($250 million). There have been cases where market forces of urban decay are confused with new urbanism in African cities. This has led to a form of suburban mixed-use development that does not promote walkability.

Australia

Most new developments on the edges of Australia's major cities are master planned, often guided expressly by the principles of New Urbanism. The relationship between housing, activity centres, the transport network and key social infrastructure (sporting facilities, libraries, community centres etc.) is defined at structure planning stage.
  • Tullimbar Village, NSW Australia, is a new development which follows the principles of New Urbanism.
Another important factor or principle of New Urbanism that guides Australia's major cities is how good their foot circulation seems to be which is guided by the wayfinding systems that are implemented. Kenneth B. Hall, Jr. and Gerald A. Porterfield said in their book, "Community by Design," the way to gain good circulation is to take some thoughtful consideration to things like wayfinding, sight lines, transition, visual clues, and reference points. Circulation design should work to create an interesting and informative system that utilizes subtle elements as well as technical ones. City of Port Philip, Australia, is a good example of wayfinding where they have come up with a comprehensive pedestrian signage system, specifically for their local areas of St Kilda, South Melbourne and Port Melbourne. The city's wayfinding system consists of 26 individually designed panels that are placed on some major streets such as St Kilda and St Kilda East, linking St Kilda Junction and Balaclava Station to the foreshore via Fitzroy, Carlisle and Acland Streets. City of Port Philip also created directional signage systems that makes use of the already existing street furniture such as trash cans to help provide for 130 directional indicators across Port Melbourne.

Desertification

From Wikipedia, the free encyclopedia

Global desertification vulnerability map
 
Lake Chad in a 2001 satellite image, with the actual lake in blue. The lake has shrunk by 94% since the 1960s.
 
Desertification is a type of land degradation in which a relatively dry area of land becomes a desert, typically losing its bodies of water as well as vegetation and wildlife. It is caused by a variety of factors, such as through climate change (particularly the current global warming) and through the overexploitation of soil through human activity. When deserts appear automatically over the natural course of a planet's life cycle, then it can be called a natural phenomenon; however, when deserts emerge due to the rampant and unchecked depletion of nutrients in soil that are essential for it to remain arable, then a virtual "soil death" can be spoken of, which traces its cause back to human overexploitation. Desertification is a significant global ecological and environmental problem with far reaching consequences on socio-economic and political conditions.

Definitions of words

Considerable controversy exists over the proper definition of the term "desertification" for which Helmut Geist (2005) has identified more than 100 formal definitions. The most widely accepted of these is that of the Princeton University Dictionary which defines it as "the process of fertile land transforming into desert typically as a result of deforestation, drought or improper/inappropriate agriculture".

Desertification has been neatly defined in the text of the United Nations Convention to Combat Desertification (UNCCD) as "land degradation in arid, semi-arid and dry sub-humid regions resulting from various factors, including climatic variations and human activities."

Another major contribution to the controversy comes from the sub-grouping of types of desertification. Spanning from the very vague yet shortsighted view as the "man-made-desert" to the broader yet less focused type as the "Non-pattern-Desert".

The earliest known discussion of the topic arose soon after the French colonization of West Africa, when the Comité d'Etudes commissioned a study on desséchement progressif to explore the prehistoric expansion of the Sahara Desert.

History

The world's most noted deserts have been formed by natural processes interacting over long intervals of time. During most of these times, deserts have grown and shrunk independent of human activities. Paleodeserts are large sand seas now inactive because they are stabilized by vegetation, some extending beyond the present margins of core deserts, such as the Sahara, the largest hot desert.

Desertification has played a significant role in human history, contributing to the collapse of several large empires, such as Carthage, Greece, and the Roman Empire, as well as causing displacement of local populations. Historical evidence shows that the serious and extensive land deterioration occurring several centuries ago in arid regions had three epicenters: the Mediterranean, the Mesopotamian Valley, and the Loess Plateau of China, where population was dense.

Areas affected

Sun, moon, and large telescopes above Chile’s Atacama Desert
 
Drylands occupy approximately 40–41% of Earth’s land area and are home to more than 2 billion people. It has been estimated that some 10–20% of drylands are already degraded, the total area affected by desertification being between 6 and 12 million square kilometres, that about 1–6% of the inhabitants of drylands live in desertified areas, and that a billion people are under threat from further desertification.

As of 1998, the then-current degree of southward expansion of the Sahara was not well known, due to a lack of recent, measurable expansion of the desert into the Sahel at the time.

The impact of global warming and human activities are presented in the Sahel. In this area, the level of desertification is very high compared to other areas in the world. All areas situated in the eastern part of Africa (i.e. in the Sahel region) are characterized by a dry climate, hot temperatures, and low rainfall (300–750 mm rainfall per year). So, droughts are the rule in the Sahel region. Some studies have shown that Africa has lost approximately 650,000 km² of its productive agricultural land over the past 50 years. The propagation of desertification in this area is considerable.

Sahel region of Mali
 
Some statistics have shown that since 1900 the Sahara has expanded by 250 km to the south over a stretch of land from west to east 6,000 km long. The survey, done by the research institute for development, had demonstrated that this means dryness is spreading fast in the Sahelian countries. 70% of the arid area has deteriorated and water resources have disappeared, leading to soil degradation. The loss of topsoil means that plants cannot take root firmly and can be uprooted by torrential water or strong winds.

The United Nations Convention (UNC) says that about six million Sahelian citizens would have to give up the desertified zones of sub-Saharan Africa for North Africa and Europe between 1997 and 2020.

Another major area that is being impacted by desertification is the Gobi Desert. Currently, the Gobi desert is the fastest moving desert on Earth; according to some researchers, the Gobi Desert swallows up over 1,300 square miles (3,370 km²) of land annually. This has destroyed many villages in its path. Currently, photos show that the Gobi Desert has expanded to the point the entire nation of Croatia could fit inside its area. This is causing a major problem for the people of China. They will soon have to deal with the desert as it creeps closer. Although the Gobi Desert itself is still a distance away from Beijing, reports from field studies state there are large sand dunes forming only 70 km (43.5 mi) outside the city.

Vegetation patterning

As the desertification takes place, the landscape may progress through different stages and continuously transform in appearance. On gradually sloped terrain, desertification can create increasingly larger empty spaces over a large strip of land, a phenomenon known as "Brousse tigrée". A mathematical model of this phenomenon proposed by C. Klausmeier attributes this patterning to dynamics in plant-water interaction. One outcome of this observation suggests an optimal planting strategy for agriculture in arid environments.

Causes by lose

Goats inside of a pen in Norte Chico, Chile. Overgrazing of drylands by poorly managed traditional herding is one of the primary causes of desertification.
 
Wildebeest in Masai Mara during the Great Migration. Overgrazing is not caused by nomadic grazers in huge populations of travel herds, nor by holistic planned grazing.
 
The immediate cause is the loss of most vegetation. This is driven by a number of factors, alone or in combination, such as drought, climatic shifts, tillage for agriculture, overgrazing and deforestation for fuel or construction materials. Vegetation plays a major role in determining the biological composition of the soil. Studies have shown that, in many environments, the rate of erosion and runoff decreases exponentially with increased vegetation cover. Unprotected, dry soil surfaces blow away with the wind or are washed away by flash floods, leaving infertile lower soil layers that bake in the sun and become an unproductive hardpan. 

Many scientists think that one of the most common causes is overgrazing, too much consumption of vegetation by cattle. Controversially, Allan Savory has claimed that the controlled movement of herds of livestock, mimicking herds of grazing wildlife, can reverse desertification.

A shepherd guiding his sheep through the high desert outside Marrakech, Morocco
 
Scientists agree that the existence of a desert in the place where the Sahara desert is now located is due to a natural climate cycle; this cycle often causes a lack of water in the area from time to time. There is a suggestion that the last time that the Sahara was converted from savanna to desert it was partially due to overgrazing by the cattle of the local population.

One of the major causes of desertification in the 20th-21st centuries is probably climate change.

Poverty

At least 90% of the inhabitants of drylands live in developing countries, where they also suffer from poor economic and social conditions. This situation is exacerbated by land degradation because of the reduction in productivity, the precariousness of living conditions and the difficulty of access to resources and opportunities.

A downward spiral is created in many underdeveloped countries by overgrazing, land exhaustion and overdrafting of groundwater in many of the marginally productive world regions due to overpopulation pressures to exploit marginal drylands for farming. Decision-makers are understandably averse to invest in arid zones with low potential. This absence of investment contributes to the marginalisation of these zones. When unfavourable agro-climatic conditions are combined with an absence of infrastructure and access to markets, as well as poorly adapted production techniques and an underfed and undereducated population, most such zones are excluded from development.

Desertification often causes rural lands to become unable to support the same sized populations that previously lived there. This results in mass migrations out of rural areas and into urban areas, particularly in Africa. These migrations into the cities often cause large numbers of unemployed people, who end up living in slums.

Agriculture is a main source of income for many desert communities. The increase in desertification in theses regions has degraded the land enough where people can no longer productively farm and make a profit. This has negatively impacted the economy and increased poverty rates.

Countermeasures

Anti-sand shields in north Sahara, Tunisia
 
Jojoba plantations, such as those shown, have played a role in combating edge effects of desertification in the Thar Desert, India.
 
Techniques and countermeasures exist for mitigating or reversing the effects of desertification, and some possess varying levels of difficulty. For some, there are numerous barriers to their implementation. Yet for others, the solution simply requires the exercise of human reason.

One proposed barrier is that the costs of adopting sustainable agricultural practices sometimes exceed the benefits for individual farmers, even while they are socially and environmentally beneficial. Another issue is a lack of political will, and lack of funding to support land reclamation and anti-desertification programs.

Desertification is recognized as a major threat to biodiversity. Some countries have developed Biodiversity Action Plans to counter its effects, particularly in relation to the protection of endangered flora and fauna.

Reforestation gets at one of the root causes of desertification and is not just a treatment of the symptoms. Environmental organizations work in places where deforestation and desertification are contributing to extreme poverty. There they focus primarily on educating the local population about the dangers of deforestation and sometimes employ them to grow seedlings, which they transfer to severely deforested areas during the rainy season. The Food and Agriculture Organization of the United Nations launched the FAO Drylands Restoration Initiative in 2012 to draw together knowledge and experience on dryland restoration. In 2015, FAO published global guidelines for the restoration of degraded forests and landscapes in drylands, in collaboration with the Turkish Ministry of Forestry and Water Affairs and the Turkish Cooperation and Coordination Agency.

The Green Wall of China is a high-profile example of one method that has been finding success in this battle with desertification.. This wall is a much larger-scale version of what American farmers did in the 1930s to stop the great Midwest dust bowl. This plan was proposed in the late 1970s, and has become a major ecological engineering project that is not predicted to end until the year 2055. According to Chinese reports, there have been nearly 66 billion trees planted in China's great green wall. Due to the success that China has been finding in stopping the spread of desertification, plans are currently be made in Africa to start a "wall" along the borders of the Sahara desert as well to be financed by the United Nations Global Environment Facility trust.

Techniques focus on two aspects: provisioning of water, and fixation and hyper-fertilizing soil. Fixating the soil is often done through the use of shelter belts, woodlots and windbreaks. Windbreaks are made from trees and bushes and are used to reduce soil erosion and evapotranspiration. They were widely encouraged by development agencies from the middle of the 1980s in the Sahel area of Africa

Some soils (for example, clay), due to lack of water can become consolidated rather than porous (as in the case of sandy soils). Some techniques as zaï or tillage are then used to still allow the planting of crops. Waffle gardens can also help as they can provide protection of the plants against wind/sandblasting, and increase the hours of shade falling on the plant.

Another technique that is useful is contour trenching. This involves the digging of 150 m long, 1 m deep trenches in the soil. The trenches are made parallel to the height lines of the landscape, preventing the water from flowing within the trenches and causing erosion. Stone walls are placed around the trenches to prevent the trenches from closing up again. The method was invented by Peter Westerveld.

Enriching of the soil and restoration of its fertility is often done by plants. Of these, leguminous plants which extract nitrogen from the air and fix it in the soil, and food crops/trees as grains, barley, beans and dates are the most important. Sand fences can also be used to control drifting of soil and sand erosion.

Some research centra (such as Bel-Air Research Center IRD/ISRA/UCAD) are also experimenting with the inoculation of tree species with mycorrhiza in arid zones. The mycorrhiza are basically fungi attaching themselves to the roots of the plants. They hereby create a symbiotic relation with the trees, increasing the surface area of the tree's roots greatly (allowing the tree to gather much more nutrients from the soil).

As there are many different types of deserts, there are also different types of desert reclamation methodologies. An example for this is the salt flats in the Rub' al Khali desert in Saudi Arabia. These salt flats are one of the most promising desert areas for seawater agriculture and could be revitalized without the use of freshwater or much energy.

Farmer-managed natural regeneration (FMNR) is another technique that has produced successful results for desert reclamation. Since 1980, this method to reforest degraded landscape has been applied with some success in Niger. This simple and low-cost method has enabled farmers to regenerate some 30,000 square kilometers in Niger. The process involves enabling native sprouting tree growth through selective pruning of shrub shoots. The residue from pruned trees can be used to provide mulching for fields thus increasing soil water retention and reducing evaporation. Additionally, properly spaced and pruned trees can increase crop yields. The Humbo Assisted Regeneration Project which uses FMNR techniques in Ethiopia has received money from The World Bank’s BioCarbon Fund, which supports projects that sequester or conserve carbon in forests or agricultural ecosystems.

Managed grazing

Restoring grasslands store CO2 from the air as plant material. Grazing livestock, usually not left to wander, would eat the grass and would minimize any grass growth while grass left alone would eventually grow to cover its own growing buds, preventing them from photosynthesizing and killing the plant. A method proposed to restore grasslands uses fences with many small paddocks and moving herds from one paddock to another after a day or two in order to mimic natural grazers and allowing the grass to grow optimally. It is estimated that increasing the carbon content of the soils in the world’s 3.5 billion hectares of agricultural grassland would offset nearly 12 years of CO2 emissions. Allan Savory, as part of holistic management, claims that while large herds are often blamed for desertification, prehistoric lands used to support large or larger herds and areas where herds were removed in the United States are still desertifying; range scientists have however not been able to experimentally confirm his claims.

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