A city is a large human settlement. Cities have extensive systems for housing, sanitation, land use, communication, their density facilitates interaction between people, government organizations and businesses, sometimes benefiting different parties in the process. City-dwellers have been a small proportion of humanity overall, but following two centuries of unprecedented and rapid urbanization half of the world population now lives in cities, which has had profound consequences for global sustainability. Present-day cities form the core of larger metropolitan areas and urban areas—creating numerous commuters traveling towards city centers for employment and edification. However, in a world of intensifying globalization, all cities are in different degree connected globally beyond these regions; the most populated city proper is Chongqing while the most populous metropolitan areas are the Greater Tokyo Area, the Shanghai area, Jabodetabek. The cities of Faiyum and Varanasi are among those laying claim to longest continual inhabitation.
A city is distinguished from other human settlements by its great size, but by its functions and its special symbolic status, which may be conferred by a central authority. The term can refer either to the physical streets and buildings of the city or to the collection of people who dwell there, can be used in a general sense to mean urban rather than rural territory. A variety of definitions, invoking population, population density, number of dwellings, economic function, infrastructure, are used in national censuses to classify populations as urban. Common population definitions for a city range between 1,500 and 50,000 people, with most U. S. states using a minimum between 5,000 inhabitants. However, some jurisdictions set no such minimums. In the United Kingdom, city status is awarded by the government and remains permanently, resulting in some small cities, such as Wells and St Davids. According to the "functional definition" a city is not distinguished by size alone, but by the role it plays within a larger political context.
Cities serve as administrative, commercial and cultural hubs for their larger surrounding areas. Examples of settlements called city which may not meet any of the traditional criteria to be named such include Broad Top City and City Dulas, Anglesey, a hamlet; the presence of a literate elite is sometimes included in the definition. A typical city has professional administrators and some form of taxation to support the government workers; the governments may be based on heredity, military power, work projects such as canal building, food distribution, land ownership, commerce, finance, or a combination of these. Societies that live in cities are called civilizations; the word city and the related civilization come, via Old French, from the Latin root civitas meaning citizenship or community member and coming to correspond with urbs, meaning city in a more physical sense. The Roman civitas was linked with the Greek "polis"—another common root appearing in English words such as metropolis. Urban geography deals both with their internal structure.
Town siting has varied through history according to natural, technological and military contexts. Access to water has long been a major factor in city placement and growth, despite exceptions enabled by the advent of rail transport in the nineteenth century, through the present most of the world's urban population lives near the coast or on a river. Urban areas as a rule cannot produce their own food and therefore must develop some relationship with a hinterland which sustains them. Only in special cases such as mining towns which play a vital role in long-distance trade, are cities disconnected from the countryside which feeds them. Thus, centrality within a productive region influences siting, as economic forces would in theory favor the creation of market places in optimal mutually reachable locations; the vast majority of cities have a central area containing buildings with special economic and religious significance. Archaeologists refer to this area by the Greek term temenos; these spaces reflect and amplify the city's centrality and importance to its wider sphere of influence.
Today cities have downtown, sometimes coincident with a central business district. Cities have public spaces where anyone can go; these include owned spaces open to the public as well as forms of public land such as public domain and the commons. Western philosophy since the time of the Greek agora has considered physical public space as the substrate of the symbolic public sphere. Public art adorns public spaces. Parks and other natural sites within cities provide residents with relief from the hardness and regularity of typical built environments. Urban structure follows one or more basic patterns: geomorphic, concentric and curvilinear. Physical environment constrains the form in which a city is built. If located on a mountainside, urban structure may rely on winding roads, it may be adapted to its means of subsistence. And it may be set up for optimal defense given the surrounding landscape. Beyond these "geomorphi
Urban geography is the subdiscipline of geography that derives from a study of cities and urban processes. Urban urbanists examine various aspects of urban life and the built environment. Scholars and the public have participated in, critiqued flows of economic and natural resources and non-human bodies, patterns of development and infrastructure and institutional activities, governance and renewal, notions of socio-spatial inclusions and everyday life. Urban geographers are concerned with the ways in which cities and towns are constructed and experienced. Alongside neighboring disciplines such as urban anthropology, urban planning and urban sociology, urban geography investigates the impact of urban processes on the earth's surface's social and physical structures. Urban geographical research can be part of physical geography; the two fundamental aspects of cities and towns, from the geographic perspective are: Location: spatial distribution and the complex patterns of movement and linkages that bind them in space.
Cities differ in their economic makeup, their social and demographic characteristics, the roles they play within the city system. One can trace these differences back to regional variations in the local resources on which growth was based during the early development of the urban pattern and in part to the subsequent shifts in the competitive advantage of regions brought about by changing locational forces affecting regional specialization within the framework of a market economy; the recognition of different city types is critical for the classification of cities in urban geography. For such classification, emphasis given in particular to functional town classification and the basic underlying dimensions of the city system; the purpose of classifying cities is twofold. On the one hand, it is undertaken to search reality for hypotheses. In this context, the recognition of different types of cities on the basis of, for example, their functional specialization may enable the identification of spatial regularities in the distribution and structure of urban functions and the formulation of hypotheses about the resulting patterns.
On the other hand, classification is undertaken to structure reality in order to test specific hypotheses that have been formulated. For example, to test the hypotheses that cities with a diversified economy grow at a faster rate those with a more specialized economic base, cities must first be classified so that diversified and specialized cities can be differentiated; the simplest way to classify cities is to identify the distinctive role they play in the city system. There are three distinct roles: central places functioning as service centers for local hinterlands transportation cities performing break-of-bulk and allied functions for larger regions specialized-function cities, dominated by one activity such as mining, manufacturing or recreation and serving national and international marketsThe composition of a city's labor force has traditionally been regarded as the best indicator of functional specialization, different city types have been most identified from the analysis of employment profiles.
Specialization in a given activity is said to exist when employment in it exceeds some critical level. The relationship between the city system and the development of manufacturing has become apparent; the rapid growth and spread of cities within the heartland-hinterland framework after 1870 was conditioned to a large extent by industrial developments, the decentralization of population within the urban system in recent years is related in large part to the movement of employment in manufacturing away from traditional industrial centers. Manufacturing is found in nearly all cities, but its importance is measured by the proportion of total earnings received by the inhabitants of an urban area; when 25 percent or more of the total earnings in an urban region derive from manufacturing, that urban area is arbitrarily designated as a manufacturing center. The location of manufacturing is affected by myriad economic and non-economic factors, such as the nature of the material inputs, the factors of production, the market and transportation costs.
Other important influences include agglomeration and external economies, public policy and personal preferences. Although it is difficult to evaluate the effect of the market on the location of manufacturing activities, two considerations are involved: the nature of and demand for the product transportation costs Urbanization, the transformation of population from rural to urban, is a major phenomenon of the modern era and a central topic of study. Urban geography arrived as a critical sub-discipline with the 1973 publication of David Harvey's Social Justice and the City, influenced by previous work by Anne Buttimer. Prior to its emergence as its own discipline, urban geography served as the academic extension of what was otherwise a professional development and planning practice. At the turn of the 19th century, urban planning began as a profession charged with mitigating the negative consequences of industrialization as documented by Friedrich Engels in his geographic analysis of the condition of the working class in England, 1844.
In a 1924 study of urban geography, Marcel Aurousseau observed that urban geography cannot be considered a subdivision of geography because it plays such an important part. However, urban geography did emerge as a specialized discipline after World War II, amidst increasing
Manuel Castells Oliván is a Spanish sociologist associated with research on the information society and globalization. The 2000–2014 research survey of the Social Sciences Citation Index ranks him as the world's fifth most-cited social science scholar, the foremost-cited communication scholar, he was awarded the 2012 Holberg Prize, for having "shaped our understanding of the political dynamics of urban and global economies in the network society." In 2013 he was awarded the Balzan Prize for Sociology. Manuel Castells was raised in La Mancha but he moved to Barcelona, where he studied Law and Economics. From a conservative family, Castells says: My parents were good parents, it was a conservative family — strongly conservative family. But I would say that the main thing that shaped my character besides my parents was the fact that I grew up in fascist Spain. It's difficult for people of the younger generation to realize what that means for the Spanish younger generation. You had to resist the whole environment, to be yourself, you had to fight and to politicize yourself from the age of fifteen or sixteen".
Castells was politically active in the student anti-Franco movement, an adolescent political activism that forced him to flee Spain for France. In Paris, at the age of 20, he completed his degree studies progressed to the University of Paris, where he earned a doctorate in sociology. At the age of twenty-four, Castells became an instructor in several Parisian universities from 1967 to 1979. In 1979, the University of California, Berkeley appointed him as professor of sociology, professor of city and regional planning. In 2001, he was a research professor at the UOC-Universitat Oberta de Barcelona. In 2003, he joined the University of Southern California Annenberg School for Communication, as a professor of communication and the first Wallis Annenberg-endowed Chair of Communication and Technology. Castells is a founding member of the USC Center on Public Diplomacy, a senior member of the diplomacy center's Faculty Advisory Council. Castells divides his residence between Spain and the US. Since 2008 he has been a member of the governing board of the European Institute of Innovation and Technology.
The sociological work of Manuel Castells synthesises empirical research literature with combinations of urban sociology, organization studies, internet studies, social movements, sociology of culture, political economy. About the origins of the network society, he posits that changes to the network form of enterprise predate the electronic internet technologies associated with network organization forms. Moreover, he coined the term "The Fourth World", denoting the sub-population excluded from the global society. Castells maintains that the Information Age can "unleash the power of the mind", which would increase the productivity of individuals and lead to greater leisure, allowing individuals to achieve "greater spiritual depth and more environmental consciousness"; such change would be positive, he argues. The Information Age, The Age of Consumption, The Network Society are all perspectives attempting to describe modern life as known in the present and to depict the future of society; as Castells suggests, contemporary society may be described as "replacing the antiquated metaphor of the machine with that of the network".
In the 1970s, following the path of Alain Touraine, Castells was a key developer of the variety of Marxist urban sociology that emphasises the role of social movements in the conflictive transformation of the city. He introduced the concept of "collective consumption" comprehending a wide range of social struggles—displaced from the economic stratum to the political stratum via state intervention. Transcending Marxist structures in the early 1980s, he concentrated upon the role of new technologies in the restructuring of an economy. In 1989, he introduced the concept of the "space of flows", the material and immaterial components of global information networks used for the real-time, long-distance co-ordination of the economy. In the 1990s, he combined his two research strands in The Information Age: Economy and Culture, published as a trilogy, The Rise of the Network Society, The Power of Identity, End of Millennium; the Information Age: Economy and Culture comprehends three sociological dimensions—production and experience—stressing that the organisation of the economy, of the state and its institutions, the ways that people create meaning in their lives through collective action, are irreducible sources of social dynamics—that must be understood as both discrete and inter-related entities.
Moreover, he became an established cybernetic culture theoretician with his Internet development analysis stressing the roles of the state, socia
Landscape architecture is the design of outdoor areas and structures to achieve environmental, social-behavioural, or aesthetic outcomes. It involves the systematic investigation of existing social and soil conditions and processes in the landscape, the design of interventions that will produce the desired outcome; the scope of the profession includes landscape design. A practitioner in the profession of landscape architecture is called a landscape architect. Landscape architecture is a multi-disciplinary field, incorporating aspects of botany, the fine arts, industrial design, soil sciences, environmental psychology, geography and civil engineering; the activities of a landscape architect can range from the creation of public parks and parkways to site planning for campuses and corporate office parks, from the design of residential estates to the design of civil infrastructure and the management of large wilderness areas or reclamation of degraded landscapes such as mines or landfills. Landscape architects work on structures and external spaces with limitations toward the landscape or park aspect of the design - large or small, urban and rural, with "hard" and "soft" materials, while integrating ecological sustainability.
The most valuable contribution can be made at the first stage of a project to generate ideas with technical understanding and creative flair for the design and use of spaces. The landscape architect can conceive the overall concept and prepare the master plan, from which detailed design drawings and technical specifications are prepared, they can review proposals to authorize and supervise contracts for the construction work. Other skills include preparing design impact assessments, conducting environmental assessments and audits, serving as an expert witness at inquiries on land use issues; the variety of the professional tasks that landscape architects collaborate on is broad, but some examples of project types include: Parks of General design and public infrastructure Sustainable development Stormwater management including rain gardens, green roofs, groundwater recharge, Green infrastructure, constructed wetlands. Landscape design for educational function and site design for public institutions and government facilities Parks, botanical gardens, arboretums and nature preserves Recreation facilities.
Coastal and offshore developments and mitigation Ecological Design any aspect of design that minimizes environmentally destructive impacts by integrating itself with natural processes and sustainabilityLandscape managers use their knowledge of landscape processes to advise on the long-term care and development of the landscape. They work in forestry, nature conservation and agriculture. Landscape scientists have specialist skills such as soil science, geomorphology or botany that they relate to the practical problems of landscape work, their projects can range from site surveys to the ecological assessment of broad areas for planning or management purposes. They may report on the impact of development or the importance of particular species in a given area. Landscape planners are concerned with landscape planning for the location, scenic and recreational aspects of urban and coastal land use, their work is embodied in written statements of policy and strategy, their remit includes master planning for new developments, landscape evaluations and assessments, preparing countryside management or policy plans.
Some may apply an additional specialism such as landscape archaeology or law to the process of landscape planning. Green roof designers design extensive and intensive roof gardens for storm water management, evapo-transpirative cooling, sustainable architecture and habitat creation. For the period before 1800, the history of landscape gardening is that of master planning and garden design for manor houses and royal properties, religious complexes, centers of government. An example is the extensive work by André Le Nôtre at Vaux-le-Vicomte for King Louis XIV of France at the Palace of Versailles; the first person to write of making a landscape was Joseph Addison in 1712. The term landscape architecture was invented by Gilbert Laing Meason in 1828, John Claudius Loudon was instrumental in the adoption of the term landscape architecture by the modern profession, he took up the term from Meason and gave it publicity in his Encyclopedias and in his 1840 book on the Landscape Gardening and Landscape Architecture of the Late Humphry Repton.
The practice of landscape architecture spread from the Old to the New World. The term "landscape architect" was
A disaster is a serious disruption, occurring over a short time, of the functioning of a community or a society involving widespread human, economic or environmental loss and impacts, which exceeds the ability of the affected community or society to cope using its own resources. In contemporary academia, disasters are seen as the consequence of inappropriately managed risk; these risks are the product of a combination of vulnerability. Hazards that strike in areas with low vulnerability will never become disasters, as in the case of uninhabited regions. Developing countries suffer the greatest costs when a disaster hits – more than 95 percent of all deaths caused by hazards occur in developing countries, losses due to natural hazards are 20 times greater in developing countries than in industrialized countries; the word disaster is derived from Middle French désastre and that from Old Italian disastro, which in turn comes from the Ancient Greek pejorative prefix δυσ-, "bad" and ἀστήρ, "star".
The root of the word disaster comes from an astrological sense of a calamity blamed on the position of planets. Researchers have been studying disasters for more than a century, for more than forty years disaster research; the studies reflect a common opinion when they argue that all disasters can be seen as being human-made, their reasoning being that human actions before the strike of the hazard can prevent it developing into a disaster. All disasters are hence the result of human failure to introduce appropriate emergency management measures. Hazards are divided into natural or human-made, although complex disasters, where there is no single root cause, are more common in developing countries. A specific disaster may spawn a secondary disaster. A classic example is an earthquake. A natural disaster is a natural process or phenomenon that may cause loss of life, injury or other health impacts, property damage, loss of livelihoods and services and economic disruption, or environmental damage.
Various phenomena like earthquakes, volcanic eruptions, hurricanes, blizzards and cyclones are all natural hazards that kill thousands of people and destroy billions of dollars of habitat and property each year. However, the rapid growth of the world's population and its increased concentration in hazardous environments has escalated both the frequency and severity of disasters. With the tropical climate and unstable landforms, coupled with deforestation, unplanned growth proliferation, non-engineered constructions make the disaster-prone areas more vulnerable. Developing countries suffer more or less chronically from natural disasters due to ineffective communication combined with insufficient budgetary allocation for disaster prevention and management. Human-instigated disasters are the consequence of human hazards. Examples include stampedes, transport accidents, industrial accidents, oil spills, nuclear explosions/nuclear radiation. War and deliberate attacks may be put in this category.
Other types of man-made disasters include the more cosmic scenarios of catastrophic global warming, nuclear war, bioterrorism. The following table notes first response initiatives. Note that whereas the sources of a disaster may be natural or man-made, the results may be similar; the Disaster Roundtable of the National Academy of Sciences EM-DAT International Disaster Database of the Centre for Research on the Epidemiology of Disasters Global Disaster Alert and Coordination System – The Global Disaster Alert and Coordination System is a joint initiative of the United Nations Office for the Coordination of Humanitarian Affairs and the European Commission UN-SPIDER – UN-SPIDER, the United Nations Programme for Space-based Information for Disaster Management and Emergency Response], a project of the United Nations Office for Outer Space Affairs
Urban planning is a technical and political process concerned with the development and design of land use and the built environment, including air and the infrastructure passing into and out of urban areas, such as transportation and distribution networks. Urban planning deals with physical layout of human settlements; the primary concern is the public welfare, which includes considerations of efficiency, sanitation and use of the environment, as well as effects on social and economic activities. Urban planning is considered an interdisciplinary field that includes social and design sciences, it is related to the field of urban design and some urban planners provide designs for streets, parks and other urban areas. Urban planning is referred to as urban and regional planning, regional planning, town planning, city planning, rural planning, urban development or some combination in various areas worldwide. Urban planning guides orderly development in urban and rural areas. Although predominantly concerned with the planning of settlements and communities, urban planning is responsible for the planning and development of water use and resources and agricultural land and conserving areas of natural environmental significance.
Practitioners of urban planning are concerned with research and analysis, strategic thinking, urban design, public consultation, policy recommendations and management. Enforcement methodologies include governmental zoning, planning permissions, building codes, as well as private easements and restrictive covenants. Urban planners work with the cognate fields of architecture, landscape architecture, civil engineering, public administration to achieve strategic and sustainability goals. Early urban planners were members of these cognate fields. Today urban planning is a independent professional discipline; the discipline is the broader category that includes different sub-fields such as land-use planning, economic development, environmental planning, transportation planning. There is evidence of urban planning and designed communities dating back to the Mesopotamian, Indus Valley and Egyptian civilizations in the third millennium BCE. Archeologists studying the ruins of cities in these areas find paved streets that were laid out at right angles in a grid pattern.
The idea of a planned out urban area evolved. Beginning in the 8th century BCE, Greek city states were centered on orthogonal plans; the ancient Romans, inspired by the Greeks used orthogonal plans for their cities. City planning in the Roman world was developed for public convenience; the spread of the Roman Empire subsequently spread the ideas of urban planning. As the Roman Empire declined, these ideas disappeared. However, many cities in Europe still held onto the planned Roman city center. Cities in Europe from the 9th to 14th centuries grew organically and sometimes chaotically, but in the following centuries some newly created towns were built according to preconceived plans, many others were enlarged with newly planned extensions. From the 15th century on, much more is recorded of the people that were involved. In this period, theoretical treatises on architecture and urban planning start to appear in which theoretical questions are addressed and designs of towns and cities are described and depicted.
During the Enlightenment period, several European rulers ambitiously attempted to redesign capital cities. During the Second French Republic, Baron Georges-Eugène Haussmann, under the direction of Napoleon III, redesigned the city of Paris into a more modern capital, with long, wide boulevards. Planning and architecture went through a paradigm shift at the turn of the 20th century; the industrialized cities of the 19th century grew at a tremendous rate. The pace and style of this industrial construction was dictated by the concerns of private business; the evils of urban life for the working poor were becoming evident as a matter for public concern. The laissez-faire style of government management of the economy, in fashion for most of the Victorian era, was starting to give way to a New Liberalism that championed intervention on the part of the poor and disadvantaged. Around 1900, theorists began developing urban planning models to mitigate the consequences of the industrial age, by providing citizens factory workers, with healthier environments.
At the beginning of the 20th century, urban planning began to be recognized as a profession. The Town and Country Planning Association was founded in 1899 and the first academic course in Great Britain on urban planning was offered by the University of Liverpool in 1909. In the 1920s, the ideas of modernism and uniformity began to surface in urban planning, lasted until the 1970s. Many planners started to believe that the ideas of modernism in urban planning led to higher crime rates and social problems. Urban planners now focus more on diversity in urban centers. Planning theory is the body of scientific concepts, behavioral relationships, assumptions that define the body of knowledge of urban planning. There are eight procedural theories of planning that remain the principal theories of planning procedure today: the rational-comprehensive approach, the incremental approach, the transactive approach, the communicative approach, the advocacy approach, the equity approach, the radical approach, the humanist or phenomenological approach.
Technical aspects of urban planning involve the applying scientific, technical processes and features that are involved