Urban ecosystems are broadly conceived to comprise the hinterlands directly managed or affected by the energy and material flows from the urban core and suburban lands, including city catchments, and peri-urban forests and cultivated land (Picket et al., 2001). Urban ecosystems are often portrayed as providing a variety of ecosystem services, including green and water structures, as well as producing a range of disservices across settlement, street, neighbourhood and regional levels (EEA, 2011). Linking the concept to the urban poor, Diaze et al. (2006) highlights the (fundamental services) that include the provision of shelter, fuel, food, water supply and wastewater collection, temperature regulation and protection from extreme weather events. Similarly, Kau et al. (2011) identify (environmental enteropathy)- a condition that impairs food absorption in children – as of the most serious disservices of pathogenesis that transmits to poor people through ecosystems. Although not fatal, the condition stunts childrens’ growth, hinders cognitive development and gives rise to illness in later life. Moreover, green and water structures located within or nearby low-income settlements are part of city-wide ecosystem networks and corridors. If well maintained, these can act as natural absorbents of storm water and natural filters of pollutants. Given the risky locations of low-income settlements, however, the corridor effect instead tends to bring regular and sudden shocks such as flooding, intensifying and diffusing environmental pollution. Urban ecosystems are, thus, both a primary concern for low-income communities and an opportunity for intervention and improvement.

The political ecology of urban change is a theoretical platform for interrogating the interrelated socio-ecological processes occurring within cities (Heynen et al., 2006). It reflects the decisions that societies make, or fail to make, about the urban environment in the context of their political environment, development opportunities and challenges, and patterns of resource distribution (Monstadt, 2009). The concept contends that there are social and political explanations as to why the urban poor have sub-optimal levels of access to green and water ecosystem services and greater exposure to disservices. Gandy (2008) illustrates this through his study of the resistance that Mumbai Municipal Authority’s good intentions to improve sanitation in slum communities met from private providers, who were making money out of existing poor sanitation conditions.

The concept of institutional diversity recognises that the sustainability of ecosystem processes and the derived services requires a variety of institutions operating at multiple levels (Ostrom, 2005). In regards to low-income settlements, it is useful to distinguish between direct and indirect agencies. Direct agencies are those with contextual attachments (e.g. grassroots organisations), duty concerns (e.g. municipal governments; NGOs; political elites) or market links (e.g. private entrepreneurs; economic elites) with the urban poor. Various incentives and trade-offs work as enablers for grassroots organisations to form collective action and, where available, to engage in co-productive arrangements with other direct agencies. Orangi Pilot Project in Karachi (Hasan, 2008) is one well-known examples in this regard. Indirect agencies, on the other hand, play important roles of advocacy, knowledge production and dissemination, and public awareness raising of the needs of low-income people. This can influence the activities of direct agencies across the city space, as Barthel et al. (2013) show in the context of ‘Ecopark’ in Stockholm. Both direct and indirect agencies can support low-income people to secure ecosystem services and/or avoid risk of disservices. The urban poors’ links are stronger with the grassroots organisations they are part of, but these links are strongly influenced by; their structural attributes (age, gender, education etc.); settlement size, age and location; and their tenure status (home owners in authorised slums; tenants etc) (Roy et al., 2013).

These concepts enable us to focus on three aspects that correspond to our three secondary research questions. First, the urban ecosystems concept helps us to focus on fundamental services and exposure to health risks from urban green and water structures as key elements representing people’s basic needs. Secondly, the political ecology concept helps us understand poor people’s existing levels of access to services and/or exposure to risks as socially-constructed. Thirdly, the institutional diversity concept helps us consider people’s collective action as just one, but significant, component of the social production of ecosystem services. We must analyse collective action in a context of complex power relations involving diverse actors, where co-production may or may not occur. A lot is dependent on the profiles of people, place and politics.