A defining feature of the 21st century is the mass rural to urban migration movements that have taken place first in the Global North during the industrial revolution of the late 1700’s and more recently in the Global South as those countries industrialise at a rapid pace (Seto, Fragkias & Gu, 2011). Such migration mostly takes place in-country (Haug, 2008) and is primarily motivated through climate or economic incentives (Barrios et al.. 2006) but often incorporates a desire to access public services upgrade lifestyles or access education. By the middle of this century we will be a predominantly urban civilisation (UN, 2015). Up to a third of the world’s population is involved in this vast human migration (Saunders, 2010) which impacts nearly everyone in some tangible way. There are approximately 498 cities globally that have over a million inhabitant, over 70% of which are located within the Global South (UN, 2016; 4). Approximately half of all urban growth in the Global South is a direct result of rural to urban migration (Smart & Smart, 2003) leading to fears that the pace of population growth outpaces the capacity of the city to sustainably absorb those migrants into the urban economy (UN, 2015; Røpke, 2006). Such a shock to the city will inveitably lead to considerable transformation of the urban space (Smart & Smart, 2003).
Migration often has economic roots (seeking opportunities for wealth creation) for the migrants as employment opportunities in the rural agricultural sector diminish to be replaced by employment in the manufacturing and services sector – urban jobs (ILO, 2017; 24). In the late 90’s and early 2000’s throughout India and China, Government policy encouraged the migration of unproductive farmers from the overpopulated rural areas to urban factories where cheap labour was in short supply (Chan, 2014). This wealth creation benefits not only migrants as it can equally generate considerable economic benefit to the host nations or city, even if migration is not always a pre-requisite. Japan for instance, with its very strict and limiting migration policies has achieved rapid economic progress in the absence of migration, while the UAE has achieved a similar rate of economic growth through reliance on mass immigration for its development (Saunders, 2010).
The economic migration phenomenon of poorer people seeking opportunities in richer places often carries negative associations for host destinations, often driven by a fear of change to established core values, cultural affinity and the depletion of scarce available (economic) resources (Buckler, Swatt, and Salinas, 2009), this is true regardless of the legality status underpinning such migration (Røpke, 2006). Such phenomenons have led to increasing politicisation of the issue either embracing such change or, as is increasingly common, turning towards isolationism and repudiation of all that is foreign (Urdal, 2008). This reluctance to integrate new-comers into the urban fabric is not unique to Global South cities as is evidenced by the recent budgetary threats made to “sanctuary cities” in the USA by President Trump (Ridgley 2008; Laughland et al., 2017; Majka & Longazel, 2017). Public policy regarding immigration differs vastly across the world, differences can take the form of legal status, rights to employment or residency, access to welfare and public services or permissible lengths of stay. There are few other subjects of public policy (or of public opinion) where the approaches taken between countries and often cities in themselves is so stark. Such policies are often emotive and reactionary (Byerlee, 1974; Røpke, 2006) even if they have sound economic foundations. In a majority of cases, restrictive public policy aimed at curbing unwanted migration fails to achieve its desired effect and only leads to increased social exclusion (Ozcurumez & Yetkın, 2014) since they fail to address the root causes of the migration and the needs of migrants themselves.
Cities can impose a variety of restrictions on rural immigration, the “hukou” system in China is such an example whereby immigrants must obtain residency permits in order to be permitted to work in cities and benefit from social support and welfare services there (Chan & Zhang, 1999). This acts as a measure to maintain public order and labour regulation. The Hukou distinguishes between agricultural and industrial labourers allowing Government policy to restrict movements according to economic imperatives and to retain labour in the countryside in order to maintain food security. The hukou system is being gradually phased out as it promotes inequality of citizens (Jiang et al., 2017). A similar system exists in Vietnam (Hardy, 2001) but with greater flexibility. South Korea had until 2008 a similar “Hoju” system of household registration but has since abandoned it as too discriminatory, enhancing rural to urban disparity and not being efficient in integrating migrants into the urban economy (Jun and Ha, 2015).
While a number of authoritative countries maintain “residency permit” requirements for would be migrants, Pyongyang, the capital of the DPRK is the most restrictive and strictly enforced (Ma and Zeng, 2015). It imposes strict “Hoju” permit requirements not only on residency and work but also on visiting and even entering city limits. Such permits are ‘earned’ through party leadership, good behaviour and intellectual ability. Beyond the Government’s desire to control migration to urban zones, particularly following a series of severe famines in the early 2000’s (Haggard and Noland, 2010), it allows the DPRK Government to maintain two distinct classes of citizens. Being a resident of Pyongyang is a privilege (which includes food security, continuous electricity, fashion choices) that may be earned or removed at will. Such draconian policies on rural immigration are not limited to command economies.
In January 2017, the mayor of Ulaanbaatar, signed a Municipal decree untitled “Restriction Action” which forbids the migration of rural Mongolians to Ulaanbaatar (with a few exceptions) until 2018 as a measure of reducing air pollution in the city (Boldsukh, 2017). Air pollution is a considerable problem in Ulaanbaatar (Brletich, 2017), and the majority of the pollution does originate in the “ger districts” (transition zones) of Ulaanbaatar (Byambadorj et al., 2011; Nishikawa et al., 2011). It is against the constitution of Mongolia to restrict freedom of movement within the territory (State Great Khural, 2009) and is a throwback to the Soviet controlled period when such “propiska” permits were commonplace (Maggs, 1961). Beyond the legality and practicality of this order, the ethical and moral dimension is particularly important in the case of Ulaanbaatar. Unlike the “hukou” system in China whereby a move of residency is permissible as a means of relocating means of production (labour), in Ulaanbaatar, this would instead bar those nomads that have lost their only assets and means of income in harsh winter conditions (their herd) and depend on urban migration and the informal economy for sheer survival (Mayer, 2015), thus reinforcing their sense of disenfranchisement and abandonment from the central Government.
Such restrictive policies are symptomatic of a perception that rural migrants remain “rural” despite living in an urban setting, that their presence thus remains temporary and they will soon either become “real” urban citizens by joining the formal economy including formal forms of housing tenure or return from whence they came, to their rural lives (Tacoli, 1988; Byerlee, 1974). Cities too often ignore those segments of the population in transition from the rural to the urban (Bayat, 2000). It is often those migrants, irrespective of their legal status that create the informal economy on which many Global South cities rely for growth and employment. Much of China’s growth since the 90’s has been fuelled by the informal sector through the dynamism and potential for innovation that this represents (Hu, 2004). Informal employment is often considered the norm rather than the exception (Jütting & de Laiglesia, 2009; 9) as it provides for greater flexibility, mobility and opportunities for employment than heavily regulated formal job markets. The relative size of the informal job sector has grown continuously in the past decades as a result of the globalisation of value chains and the outsourcing of industrial processes. An estimated 60% of all non-agricultural jobs in Latin America, 75% in SouthEast Asia and 85% in Sub- Saharan Africa are in the informal sector (Jütting and de Laiglesia, 2009; 33).
Despite its advantages, informal sector led growth should remain a temporary phenomenon since it impacts overall economic productivity as informal sector firms fear persecutions and thus remain small, do not invest in long term growth and have limited access to formal debt markets or the ability to engage in formal contractual relationships (La Porta and Shleifer, 2008), thus lacking legal recognition and protection (OECD, 2004; Levy, 2008). It is essential to incentivise cities to provide “better” jobs, even if within the informal economy (Paci and Serneels, 2007) so that labour, as a productive asset, becomes more efficient. While the informal economy represents the most efficient path out of poverty in Global South countries (Lundström and Ronnas, 2006). Many migrants suffer from considerable inequality of income and status within those informal settlements (UN-Habitat, 2003). Many of the migrants will work in the informal sectors initially (Mukoko 1996; Piche & Gingras 1998) before (re)-joining the formal sector once financial security and some form of secured housing tenure is achieved (Cohen, 2011). In 2004 the majority of revenue in rural China was no longer derived from agriculture but from remittances sent from earlier migrants (Wildau, 2015; Liu, 2015). This both creates financial security for the receivers but catalyses the urbanisation of the villages into more formal and denser urban areas (Narayan et al., 2009). The rate of remittances drop steadily the longer time elapses form the initial migration but never truly stop since it provides a safety net should urban entrepreneurial adventures fail (Cohen, 2011) and the relative value of money is much higher in the rural zones, allowing for greater spending power. Those remittances reduce the sustainability of the city since it creates capital leakage which is not being invested in purchasing permanent housing, services or employment in the host city.
Migration in the Global South takes many forms and is more complex than simply a series of push (hardships, starvation, political persecutions) or pull (income generation, family, political incentives) factors. In Chinese cities for instance there has been considerable de-facto migration as cities grew spatially larger and started encompassing nearby settlements and villages, even if not officially recognised by the authorities as being part of the larger metropolitan areas, thereby leading to intra- urban mobility (Saunders, 2010). It is this formalisation of semi-urban neighbouring agglomerations that is (in the Chinese contemporary context) the most significant contributor to urban population growth (Chan, 2014). Those urban villages (cun), in turn become destination (or arrival) villages for rural migrants, a first point of transition before either moving deeper into the city or returning home to rural life out of desperation and resignation (Chan, 2014, Saunders, 2010) or as part of cyclical migratory movements driven by agricultural seasons, political movements or life events such as marriage or retirement (Bayat, 2000). Charles Tilly, an American sociologist (1978) classified migration as either circular whereby tradesmen or professionals would regularly move to the city for particular (often seasonal) jobs before returning to their rural environment, career driven where semi-professional migrants would move and establish themselves in a particular career and stay there. He also identified a form of migration he called chain-migration (p.57) whereby initial migrants would become essential support networks in facilitating the future urban migration of relatives left in their original villages. Skeldon (1977) examined such chain-migration patterns between a village in Peru named Cuzco and the capital Lima. He found that within a few years to 2 generations of back and forth movements between the city and the village, a tipping point would be reached and “migration transition” would be achieved where movement back to the village would cease as the majority of the initial migrants dependents are now urban. Skeldon (1977) concluded that the length of time it would take for such transition would be dependent on education and communication (p. 445) since better education generally leads to a faster transition to the formal economy.
During the 30 years since 1979, China’s rapid rate of urbanisation has led to an increase to the urban population of approximately 440 million to 622 million in 2009 (Kam Wing, Bellwood, 2013). In 2013 alone, an estimated 40 Million rural migrants moved to transitional urban spaces within China (Saunders, 2010) making this process one of the largest in-country migration movements in our history. China is now reaching its Lewis Turning Point (Liu, 2015; 404) whereby the labour surplus in the countryside has been absorbed in the cities and wages will rise as inbound migration slows. Despite a similar phenomenon being witnessed globally, such massive migrational movements continue to test municipalities ability to provide urban services and infrastructure to all, straining public resources beyond their breaking point (Jiang et al., 2017) and leading to poor urban management and disenfranchisement of entire communities (Frenkel & Ashkenazi, 2008; Hasse & Lathrop, 2003; Bayat, 2000). Mumbai’s population has doubled since 1991 to 20 Million people, 41% of which live in slums with little upward mobility (UN, 2016). The higher living standards found in urban areas (Østby, 2016) and the subsequent mismanagement of this urban population influx has led to social tensions since the newly arrived feel un-welcomed, excluded and rejected by the resident urban populations who fear change (Buckler, Swatt, and Salinas, 2009). This can manifest itself in the form of urban violence (Brennan, 1999; 17), rising food prices (Hendrix et al., 2009) or political eviction (Suckall et al., 2015).
Formal land tenure and top-down urban planning common in the Global South continue to create barriers to recent migrants in attaining formal urban livelihood (Parnell & Walawege, 2011). Such systems of segregation and legal differentiation between established urban residents and rural migrants deepen their sense of exclusion and reinforces the immigrants desire to create a new urban identity and a standing within this new spatial order (Dubovyk, Sliuzas, & Flacke, 2011). Resilient communities and distinct place-making are created despite the pressures of social exclusion but result in increasingly fragmented societies (Watson 2009; Shen et al., 2017). This is exasperated by poor provision of urban services and infrastructure in those transitional urban zones as the costs to the municipality is prohibitive, in particular since transition zones generate little fiscal revenue (Hasse & Lathrop, 2003).
A continuous struggle in achieving sustainability has been the continued growth of population versus the utilisation of scarce resources (Brennan, 1999), simply put, the world’s population is growing faster than our use of resources can support. Yet, it is more sustainable in terms of climate change, economic growth and transport efficiencies to densify the population into a restrained spatial area than to have the same population spread over a large geographical space (Agunbiade et al., 2012). An additional positive externality from a sustainability aspect of the rural to urban migration movement within the Global South is that as rural populations migrate to urban areas, population growth rates generally contract. Rural migrants see a drop in the family size on average by one child within the first generation (Sato, 2007; Saunders, 2010), often to less than 2.1 children per family, the steady population rate required to maintain equilibrium. The UN (2015) predicts that, in part due to urban migration movements, by 2050, the global population will stop growing.
Sustainability in cities is also based on the efficient use of available scarce resources so as not to deplete them for future generations, this efficiency can only be achieved through good urban governance, which encourages community integration and empowerment (Beauchemin & Bocquier 2004) of all citizens into the economic, political and social systems of the city (Bayat, 2000). The strength of institutions is thus paramount to strengthen the rule of law, the rights of property ownership, the sanctity of contracts, the equality of all citizens and the right to migrate in order to create sustainable urban development (Treblicock & Prado, 2011). With weak institutions, corruption, nepotism and discrimination will continue to undermine the fair and equitable development and regeneration of the city. The way migration is perceived by the citizens and policy makers of the host city will decide the method of integration of those citizens within its urban fabric and thus define its urban form and impact.
In summary, urban migration to Global South cities lowers fertility rates (Kemper, 1977; Sato, 2007), relieves the ‘burden of the elderly’ by bringing in a younger demographic population (Røpke, 2006) increases education levels (Miller, 2011), improves gender equality (Ross-Sheriff, 2011), creates economic opportunities (Byerlee, 1974) and allows for greater efficiencies in the use of resources (Heugh, 2013) through economies of scale. A greater percentage of urban population within a country reduces the impact of climate change (Zhang & Shufeng, 2003; Barrios et al., 2006), reduces the need for extensive distribution and transport infrastructure and reduces the overall cost of Government to provide public services (Hasse & Lathrop, 2003), thus freeing up resources for other uses while improving overall urban resilience. The high prevalence of the informal economy in the urban sector is an effective method to raise individuals out of poverty (Islam, 2006) which, coupled with a higher population densification, provides improved access to markets and economic opportunities (Osmani, 2005). The gradual formalisation of the economy will lead to a widening of the tax base and improved labour productivity. As the migration movement slows and 2nd generation immigrants settle and bring their dependents into the economic life of the city, capital leakage in the form of remittances which currently supports home villages will slow down and will be invested in the city, leading to a more significant intra-urban injection multiplier effect (Cohen, 2011; Jun and Ha, 2015). Rural migration is the essential fuel that supplies the socio-economic engine of the city and is thus essential for its continued sustainability.
Over the shorter term, excessive migration patterns may hinder the adoption of policies that are required for ecological and economic sustainability (Rees, 2006), may overburden limited public resources and may lead to a disparity of status and opportunities between citizens. Over the longer term, there is little doubt that reasonable rural to urban migration movements within Global South cities will lead towards greater sustainability if the process is managed properly (Røpke, 2006), if public policy adopts a language of adaptation and integration of new arrivals through strong institutions (Heugh, 2013; Jun and Ha, 2015), if resources are allocated efficiently and if the nation’s overall sustainability is in itself not put at risk through excessive urbanisation (Jiang et al., 2017).
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