Regional and Settlement Planning, GIS and Management

Primate city and megalopolis theories

A primate city is the largest city of a country, and it is disproportionately large compared with the next-largest cities, so the urban system is dominated by one centre. Mark Jefferson introduced the term in 1939 in his paper 'The Law of the Primate City', and the concept is often contrasted with the rank-size rule, under which city sizes follow a regular hierarchy. Primacy is commonly judged by comparing the population of the largest city with that of the second city. A primate city is usually also the political and economic capital, which is why the pattern is common in many developing countries. A megalopolis, a term used by Jean Gottmann, is a vast, continuous chain of metropolitan regions, and it is different from a primate city. Europe's Blue Banana is a linear megalopolitan zone of high population density and economic activity that runs from south-east England through the Low Countries and the Rhine valley to northern Italy. The Golden Polygon is a different, polygon-shaped region of dense economic activity, so the two should not be confused. In Doxiadis's Ekistics logarithmic scale, human settlements are arranged by size, from the individual dwelling upward, and the largest unit, covering the whole inhabited world, is the ecumenopolis, which corresponds to the world city.

GIS raster data model

A raster data model stores geographic information as a regular grid of rectangular cells. Each cell is a pixel (picture element), which is the smallest entity of a raster dataset, and it holds a single value representing the attribute of the area it covers. Vector data represents features as points, lines and polygons defined by coordinates and connected vertices, so lines, points and polygons are vector entities rather than raster units. A Digital Elevation Model is a classic raster dataset because elevation is sampled at each cell of a regular grid, with one value per cell. Tabular data holds attribute records without a spatial grid, and it is therefore not a spatial data type of this kind. A satellite image is a typical raster, while a digitised road network is typically stored as vector lines.

Land acquisition law (LARR 2013)

The Right to Fair Compensation and Transparency in Land Acquisition, Rehabilitation and Resettlement Act, 2013 allows the appropriate government, under Section 40, to dispense with the normal acquisition procedure in cases of urgency. The urgency provision may be invoked for national defence and security, and for emergencies arising from natural calamities or other emergencies. Affordable housing and industrial projects are not listed as urgency grounds, so they follow the regular procedure of the Act. Under the Act, the Collector determines the market value of land, using criteria such as the value in registered sale deeds and the average sale price of similar land in the vicinity. Compensation is calculated on this market value, not on the circle rate, which is a stamp-duty reference value, and it is not determined by a planning officer.

Urban settlement typologies India

Indian planning uses several settlement typologies. A satellite town is a planned town developed at some distance from a large city to decongest it, and it is linked to the core by transport. A counter magnet is a city deliberately developed to divert migration and growth away from an overcrowded metropolitan region. An urban agglomeration, as a census concept, is a continuous urban spread that includes a city and its outgrowths. A university town is built around a university campus, and an investment region is a large area designated to attract industrial investment, such as along an industrial corridor. The Census of India 2011 defines a Census Town as a place that is not a Statutory Town but has a minimum population of 5000, a population density of at least 400 persons per square kilometre, and at least 75 percent of its male main workers engaged in non-agricultural pursuits. Statements about a 250 persons per square kilometre density or a 55 percent employment threshold are therefore incorrect.

Indian government infrastructure schemes

SVAMITVA, run by the Ministry of Panchayati Raj, aims to establish clear ownership of property in rural inhabited (Abadi) areas. It maps land parcels using drone and other improved survey technology and issues property cards to households. Several other schemes address different rural and urban needs and should not be confused with it. The Jal Jeevan Mission provides tap water connections, the Mahatma Gandhi National Rural Employment Guarantee Act provides the right to work, and the National Rural Livelihoods Mission works on sustainable livelihoods. PM Gati Shakti is the National Master Plan for Multi-modal Connectivity, launched in 2021, which integrates infrastructure planning of different ministries on a common geospatial platform. Bharatmala is a programme for the national highway network, Parvatmala for ropeways in hilly areas, and Sagarmala for port-led development.

Population projection methods

The geometric increase method projects population by assuming a constant compound growth rate, so that P_n = P_0(1+r)^n, where r is the average growth rate per period. The average rate is obtained from the geometric mean of the successive ratios of population, which gives r = (P_n/P_0)^{1/n} - 1 for a single span. For example, a population of 40,000 growing at 4 percent per decade gives 40000 \times 1.04^3 \approx 44{,}995 after three decades. When a sex ratio is expressed as females per 1000 males, the female share of the total population is \frac{SR}{1000+SR}, where SR is the sex ratio. The female population is then obtained by multiplying the total projected population by this share, after the sex ratio has been projected forward at its given growth rate.

Urban spatial patterns (satellite town, TOD, CBD)

A satellite town is a self-contained settlement located beyond the built-up boundary of a city and linked to it by highway or rail. The urban fringe is the transitional zone that straddles the city boundary, where urban and rural land uses mix. Transit-oriented development (TOD) is high-density, mixed-use development concentrated around a metro or rail station to encourage transit use. The central business district (CBD) is the compact core of the city with the highest land values, offices and retail. Recognising these four patterns in a city diagram requires locating the settlement beyond the boundary, the zone straddling the boundary, the station-centred cluster and the central core.

Multi-criteria decision analysis

Multi-criteria decision analysis evaluates alternatives against several criteria by assigning weights to the criteria. The analytical hierarchy process (AHP), developed by Thomas Saaty, derives these weights from a pairwise comparison matrix in which each criterion is compared with every other criterion, usually on a 1 to 9 scale. The weights are obtained as the principal eigenvector of this matrix, and a consistency ratio, commonly kept below 0.1, checks the coherence of the judgements. Other statistical methods do not use such a matrix of criteria. Exploratory factor analysis works on the correlations among observed variables, latent class analysis identifies unobserved subgroups in categorical data, and multiple linear regression estimates coefficients by least squares.

URDPFI settlement classification

The URDPFI Guidelines (2015) classify urban settlements in a hierarchy by population size. Under this classification, a large city corresponds to a population of 5 lakh to 10 lakh, a metropolitan city II to 50 lakh to 1 crore, a small town II to 20,000 to 50,000, and a medium town I to 50,000 to 1 lakh. Each class must therefore be matched to its own population range rather than to a neighbouring range.

Remote sensing satellites India

Each Indian remote sensing or navigation mission serves a particular application. SCATSAT-1 is a scatterometer that measures ocean surface winds, which supports cyclone monitoring and prediction. The GSAT series consists of geostationary communication satellites, so GSAT-30 serves communication rather than mapping. CARTOSAT satellites carry high-resolution imaging sensors for cartography and mapping, with CARTOSAT-3 providing very high resolution imagery. IRNSS, now known as NavIC, is India's regional navigation satellite system. HySIS is an Earth observation satellite with a hyperspectral imager, so it is an imaging satellite rather than a communication satellite.

73rd Amendment institutions

The 73rd Constitutional Amendment Act, 1992 inserted Part IX into the Constitution to provide for rural local self-government. It mandates Panchayats at the village, intermediate and district levels under Article 243B. The Gram Sabha, the body of registered voters of a village, is provided under Article 243A of the same amendment. Municipal councils and ward committees are institutions of urban local government, and they were introduced by the 74th Constitutional Amendment Act, 1992, so the 73rd Amendment does not mandate them.

Satellite image land use classification

Land use classification from satellite images is usually carried out by pixel-based classifiers that assign each pixel to a class using its spectral values. Maximum likelihood is a supervised statistical classifier that assigns each pixel to the class with the highest probability. K-means is an unsupervised clustering method that groups pixels with similar spectral signatures into classes. Artificial neural networks are trained classifiers that map spectral and texture features to land use classes. The northwest corner method, by contrast, is a technique for finding an initial basic feasible solution to a transportation problem in operations research, so it has no role in image classification.

Municipal revenue sources

Municipal bodies mobilise their own-source revenue through taxes and charges they are empowered to levy. Property tax is a principal own-source tax on land and buildings within the municipal area. Development charges are levied on developers to recover the cost of infrastructure such as roads, water supply and drainage, so they are also a municipal fiscal resource. Income tax is levied by the Union or State governments and is not a municipal revenue instrument, while salaries of municipal staff are an item of expenditure, not a source of revenue.

Urban growth terminology

Several terms describe urban growth and form. An edge city is a secondary business district located on the periphery of a metropolitan area, with offices, retail and jobs away from the old core. Synekism is the historical process by which several small settlements unite under a single governing authority to form one city. Urbicide is the deliberate destruction of a city and its built environment, which is a form of violence against the city. Urban sprawl is the rapid, low-density expansion of urban areas into surrounding land, whereas the rebuilding of a core area is urban renewal or regeneration, a separate concept.

URDPFI education facility norms

The URDPFI Guidelines (2015) specify the minimum population to be served by each type of educational facility. A primary school is planned for about 4,000 population, a senior secondary school for about 7,500, an integrated school for about 90,000, and a college for about 1,25,000. These norms are used to estimate the number of facilities a settlement needs, so each school level must be matched to its own population threshold.

Demographic dividend

The demographic dividend is the potential for faster economic growth that arises when the working-age population, conventionally aged 15 to 64, forms a larger share of the total population than the dependent population of children and the elderly. Realising the dividend requires that the working-age population finds productive employment, so sufficient job creation is a necessary condition. If the working-age population cannot find jobs, the same age structure can produce unemployment and social strain, so the dividend is not guaranteed and can turn into a demographic disaster.