Addressing the urban challenge
Breadth of the issue – How are the problem(s) that are being tackled by your initiative affecting citizens/local businesses or a significant component of the local wildlife?
Due to its geographical location and orographic characteristics, Mexico City is a system exposed to various climatic and hydrometeorological hazards. Because of anthropogenic factors such as overexploitation, expansion of the urban sprawl, changes in land use, soil, water and air pollution (the city emits 27 million tons of carbon dioxide equivalent) and the effects of climate change, the city faces problematic situations caused and intensified by the deterioration of ecosystems and the loss of its biodiversity.
There is a large amount of evidence on the intensification of the effects of climate change and the deepening of the conditions of the environmental problem in the city, which led to the establishment of very ambitious goals in 2019 to reverse these conditions, such as a 10% reduction in CO2equivalent emissions, compared to those produced in 2018.
The most important effects that directly impact the inhabitants have to do with material and human losses due to extreme rains, floods and landslides (between the years 2000 and 2015 there were 51 events of this type that affected 52,331 people), urban heat islands and temperatures extreme high temperatures that, combined with changes in rainfall patterns, generate conditions for a greater incidence of fires that contribute to the loss of ecosystems (from 2019 to 2020, the area affected by fires in conservation land had been reduced by 50% thanks to the increased resources for its attention, but in 2021 the affected area doubled due to a severe drought condition linked to the ENSO-Niña climatic phenomenon).
Depth of the issue – How seriously are the problems being tackled by your initiative impacting the life of the citizens/businesses/wildlife concerned?
There is great evidence on the intensification of the effects of climate change and the environmental problems in the city that led to the establishment of much more ambitious goals in 2019 to reverse these conditions. Between 2000 and 2015, Mexico City registered a total of 66 hydrometeorological phenomena, whose impacts are the most costly and damaging due to the impacted extensions and the affected population. The most frequent were related to torrential rains and storms, landslides, low temperatures and strong winds, which caused damages of 1,173,876 million pesos (56 million dollars), affecting 11,107 homes and 64,655 people (Source: National Center for Disaster Prevention).
Also, from 1991 to 2020, 12,332 fires were registered in the city, 10.6% of the fires in the country (Source: National Forestry Commission) and the temperature in the urban area has increased up to 5°C with respect to the rural area in the dry season of the year and 4% with respect to its surroundings (mainly urban areas with cement and asphalt structures).
In the city there are 105 species in some category of risk and at the beginning of this century more than 70% of the extension of oak and pine-oak forests had already been lost (Source: CONABIO; http://22.214.171.124/janium /Documents/13054.pdf).
It’s estimated that for each urbanized hectare, the aquifers stop recharging 2.5 million liters per year, in a context in which the area built on conservation land from 2005 to 2015 increased an annual average of 2.67%, reaching 5,518.69 hectares in 2015 (Source: IG-UNAM/SEDEMA, 2017).
The power of plants and natural ecosystems to deliver benefits
How is the initiative shaped by scientific evidence of the potential for plants and natural ecosystems to deliver benefits?
We decided to unite the city with nature, so we developed a Special Green Infrastructure Program (SGIP) that provides the city with adequate criteria and guidelines for incorporating and increasing accessibility to green areas and blue spaces (rivers, lakes, water channels and wetlands), with a focus on solutions based on nature and in accordance with the socio-environmental characteristics of the eight regions that were established:
- North Urban Green Areas
- Urban canyons
- Urban Green Areas West Center
- Urban Green Areas East Center
- Eastern Urban Green Areas
- Rural-Urban Transition
- Natural Forests
The proportion of specimens per vegetal stratum that is necessary to achieve a better development of the plantations was technically defined. In the conservation land, a proportion of 85% of trees, 13% of shrubs and 2% of herbaceous and ground cover has been maintained, and a practically inverse proportion in urban land.
The planning of interventions is carried out considering the EGIP, the catalogue of species that was prepared in 2019 (based on the potential to generate pollination processes, strengthen soils, regulate climate and air quality, increase water infiltration, reduce hydrometeorological risks and resist the environmental conditions before anthropogenic activities) and the specific conditions of the site. On the conservation land, potential quadrants to be restored are identified considering:
- Areas affected by forest fires that occurred in the previous three years
- Vegetation zones generated by the National Institute of Statistical and Geographical Information
- Spectral signatures of vegetation
How has the city exploited the potential of plants and associated ecosystems to deliver more than one benefit?
The Special Green Infrastructure Program for Mexico City (SGIP) establishes the planning and strategic design of the interventions considering the following criteria: environmental aspects (type of climate, average annual temperature and precipitation, types of soil, altitude interval, land use and vegetation, presence of natural protected areas and green areas in the city), social (number of inhabitants, area of green area per capita, habitability index), risks aspects (hydrometeorological, geological and chemical-technological) and the principles of connectivity, accessibility, functionality and resilience.
This condition has been reflected in the diversity of intervened spaces, allowing natural forests, natural protected areas, ravines, rivers, wetlands and natural ecosystems to generate multiple socio-environmental benefits such as reducing atmospheric pollutants, increasing aquifer recharge, reducing risks from flooding and landslides, and provide habitat for wildlife; while other spaces with nature, such as parks and urban green corridors, also offer more accessibility to public spaces, reduce the effect of heat islands and reduce flooding.
One concrete example: the intervention of 2.07 hectares in Mexico City Ecological Park included components with positive ecological impacts (revegetation of 5,574 m2 with native species), as well as others with social benefits (rehabilitation of two kilometers of cycle paths, 60 solar lights and the opening of four viewpoints, one guardhouse and two permeable parking lots), benefiting 62,400 annual visitors.
It’s possible to, simultaneously, face the effects of climate change, counteract loss of biodiversity, promote urban resilience and contribute to well-being and the fulfillment of the human right to a healthy environment, water and public space.
Innovative and Collaborative Solution
How does the initiative show evidence of feasibility, including on-going financial and logistical support?
The financial and logistical feasibility is based on the following conditions and actions:
- The Altépetl, Reto Verde and Sowing Parks programs are part of the ones that have been defined as priority programs by the Government of Mexico City, which entails institutional and financial support.
- In the particular case of the Altépetl program, the historical investment of 1,000 million pesos per year to attend to conservation land stands out, which represents an increase of 300% in relation to the annual investment that was destined for this area of the city before of 2019.
- A collaboration that we generated with the Finance Initiative for Biodiversity (Biofin) of the United Nations Development Program (UNDP), for the design of financing solutions that will improve the government’s capacities to spend public resources more efficiently and maximize profits.
- The application of tax incentives to promote citizen and private sector participation in revegetation through the maintenance and creation of green areas, gardens for pollinators, and urban orchards.
- The promotion of the establishment of community conservation areas (ACC, by its initials in Spanish) so that rural communities manage their own conservation areas with community management, based on training, technical advice and support.
In what ways is the initiative innovative?
The Green Challenge incorporates the directive of the current Government of Mexico City’s motto “City of Rights and Innovation” through:
- Replacement of the traditional development paradigm that generated a dichotomy between the “city” and nature, as opposing elements; and it’s replacement with an integration paradigm that re-balances the artificial and natural components of the urban territorial system and evidence and intensify the relations between the urban area (41% of the territory) and the rural and natural territory (59%), for which, the SGIP establishes the “rural-urban transition” region as one of the zones.
- Rescue of native biodiversity. It promotes the identity of the inhabitants with their city and ecological interactions through gardens and corridors for pollinators and the “reconversion” of nurseries to diversify species.
- Gardens for pollinators. In response to the threat faced by pollinating animals due to the loss of habitat caused by urban growth and the use of pesticides in agriculture and green areas, we are creating a network of pollination corridors to increase the connectivity between urban and rural natural areas, in benefit of key animal species for pollination (birds, insects and mammals) and the production of food in rural territories.
- The revegetation strategy was decentralized, calling for a participation scheme open to citizens and all sectors: more than 170 participatory planting days prior to the pandemic, “adoption” of green areas for their maintenance, donation of supplies for plantations and guides to promote the creation of green areas in the home (pollinating gardens and urban orchards).
How is the initiative supported by collaborative working across disciplines and sectors?
Trans-sectoral and transdisciplinary work is essential for the effectiveness of interventions. The Green Challenge has involved the coordination of a large number of areas and specialists, more than 4 thousand brigade members from rural communities and neighbors, companies and organizations within the urban area:
- International cooperation agencies, civil society, academic and research organizations that collaborated in the participatory design of Mexico City Climate Action Program (ELAC, by its acronym in Spanish) and the Strategy for the Conservation and Sustainable Use of Biodiversity in Mexico City (ECUSBE, by its acronym in Spanish).
- Direction of Green Infrastructure, whose landscape architects, biologists and engineers design and advise the projects
- Secretariat of Works and Services that executes works and maintains interventions in parks and main avenues
- Commission of Natural Resources and Rural Development, whose forest engineers coordinate the work on the conservation land
- Mexico City Water System, whose engineers and hydrologists lead the rescue of rivers
- Governments of the 16 municipalities that are an essential channel of information and management on the conditions of their territory and the demands of neighbors
- Secretariat of Education, Science, Technology and Innovation that collaborated in the project for the rescue of native species and pollinators of the Valley of Mexico
- Digital Agency for Public Innovation, which designed the platform to show the progress of the Green Challenge in the city territory
- Biologists and communicologists from the Executive Direction of Environmental Culture who produce guides and materials to promote green areas and the informed participation of citizens
How does the initiative demonstrate evidence of community support?
Interventions have a very important social base in the planning, design, implementation, maintenance and evaluation processes.
Within the conservation ground:
- There is broad support from the communities, since it is the rural communities themselves who carry out the revegetation activities, for which they receive financial compensation, equipment, training and support from the Secretariat of Environment of Mexico City.
- The establishment of community conservation areas (currently 25 occupying 17,962 hectares) agreed upon and managed by the communities themselves is promoted, which guarantees their support for the application of management programs that are prepared with the support of the government.
In the 25 natural protected areas (21,709 hectares):
- The advisory councils conformed by the public sector, academia, civil society organizations and neighborhood representatives are essential for decision-making and support in the management of these spaces.
In urban areas:
- The neighborhood assemblies participate through the relationship with the municipal governments to give their opinion and, on occasions, participate in the interventions.
- Neighborhood interest and participation has been key, thanks to them more than 170 workshops were organized in sites that were revegetated together with the neighbors themselves.
- The academic community is essential for different projects. The Botanical Garden of the National Autonomous University of Mexico is an ally in the recovery of native species and the College of Postgraduates in the identification of causes of mortality and care plans for plant species.
- Companies have invested to donate supplies (mainly tools) and adopt sites (essentially ridges that are maintained for one or two years).
Implementation, Impact and Replicability
How does the initiative demonstrate evidence of a track record of success against pursued objectives?
The Green Challenge of Mexico City established the goal of planting 10 million trees and plants. To date, 27,082,593 have been planted. This was possible at the confluence of the coordinated effort of all sectors. In short, thanks to:
- Productive improvement of the three government nurseries, which went from having an annual production of less than 500 thousand specimens in 2018 to more than 10 million in 2021.
- “Altépetl” program which financially supports 4,155 brigade members from rural communities who carry out conservation activities and have planted 16.9 million specimens in conservation land, including tree planting on 16,505 hectares of forests and rivers. Altépetl has provided direct financial support to 37,741 people who carry out conservation and agroecological activities, with a positive impact on 128,319 rural inhabitants.
- Participation of citizens and companies, in more than 170 participatory planting sessions in the 16 municipalities of Mexico City.
- “Sowing Parks” program, with an investment of more than 2,800 million pesos (more than 135 million dollars) for the creation and rehabilitation of 16 large parks with new green areas and sports, recreational and cultural infrastructure on 500 intervened hectares (four urban parks, two urban forests, five protected natural areas, four linear parks on avenues and a canal).
- “Gardens for Life” program, with 35 pollination gardening courses to 598 people, mainly women, and the creation of 535 gardens for pollinators which, together with other spaces, have added up to 608 new gardens of this type to the city.
How has the initiative had a ripple effect beyond the scope of the initiative itself, thereby demonstrating a change in the city’s and/or its partners’ way of working with plants?
The Green Challenge began in 2019 with the goal of planting 10 million trees and other plants. However, more and more social and private actors have joined and have contributed to the planting of more than 27 million specimens. Each intervention arouses the interest of the inhabitants and sublocal governments in replicating the green areas. Coordination between authorities as a main element of the initiative has made the attention to these needs increasingly efficient.
Different strategies have made it possible to generate a positive change in the relationship between the inhabitants and their natural spaces, causing cascading actions associated with capacity building and revegetation of the city. They are between them:
- Strategy of communication and citizen involvement through participatory planting days in all the territorial demarcations of the city, every weekend for almost six months (June to November 2019) so that people feel the trees are theirs and plants that they planted, committing themselves to their care.
- Caravan of Rural Producers of Conservation Land, created with the aim of generating itinerant points of sale within the urban area (shopping malls and public spaces) where producers of traditional crops, such as cempasúchil and poinsettia, market its products, increasing the percentage of sales and the valuation of these crops that are part of the national identity.
- Creation of environmental educational materials: “Guide for the creation of pollinating gardens” (http://data.sedema.cdmx.gob.mx/flippingbook/mujeres-polinizadoras/mobile/index.html#p=1) and “Guide for urban family gardens” (https://www.sedema.cdmx.gob.mx/storage/app/media/GuiaHuertosUrbanosFamiliares.pdf), which became more relevant during confinement due to the pandemic,
How have other cities expressed interest in the initiative, or what potential does it have to interest other cities and be customised to their own circumstances?
The “green infrastructure” concept is of recent appearance in government agendas, and there are principles that make it a milestone for development planning, considering the increasing importance given to the natural environment, social impact and mitigation to climate change.
Mexico City is part of the Metropolitan Zone of the Valley of Mexico (ZMVM), in conjunction with parts of the State of Mexico and the state of Hidalgo. This region has socio-environmental and economic conditions that cannot be addressed in isolation. The State of Mexico created its first Green Infrastructure Plan in its capital (Toluca) and an historic collaboration with Mexico City will allow the rehabilitation of “Río de los Remedios” river (15.7 kilometers), which crosses territorial demarcations in both territories. The SGIP has also motivated the creation of a management program based on Green Infrastructure in two southeast Mexican cities: Campeche (Campeche) and Mérida (Yucatán).
This strategy provides a systemic vision that can be adapted to each city, since it is based on a combination of global conditions (loss of biodiversity, ecosystems, climate change) and local elements that can be developed locally (classification by regions, selection of native species, involvement of all sectors).
To achieve comprehensive interventions with socio-environmental benefits, as well as the widest possible scope, given the depth of the environmental crisis, it is desirable a combination of priority interventions defined by the government and an open call to all sectors that creates incentives in a context in which the effort and recognition belongs to all.
Sustainability and Resilience
What efforts have been made to reduce the carbon footprint of the initiative?
The Direction of Climate Change and Sustainable Projects monitors and quantifies the impacts of the Environmental and Climate Change Program (ECCP) of Mexico City in each of its 7 axes (Revegetation of the countryside and the city, Rescue of rivers and water bodies, Sustainable water management, Zero waste, Integrated and sustainable mobility, Air quality and Solar city). In this sense, interventions for “Revegetation of the countryside and the city” are already contributing to mitigate 74,249 tons of CO2e per year.
In addition, the following actions contribute to reducing the carbon footprint:
- Increased local production of plants in our nurseries has allowed us to reduce the acquisition of other sites outside the city, reducing the carbon footprint associated with the transfer
- Strengthening of food production in the countryside of the city, promotion of other forms of urban agriculture (urban orchards) and promotion of local consumption of these products
- The use of organic waste to produce compost helps reduce the extraction of forest land, improve the city’s soils and preserve the ecological functions of carbon sequestration
- The increase in green areas and accessibility to public spaces through the “Sowing Parks” program, associated with an efficient integrated mobility plan (as part of another axis of ECCP), reduces travel times and distances, in addition to replace other types of recreational activities that involve car travel
- The use of construction waste and the application of nature-based solutions contribute to the goals of mitigating emissions of greenhouse gases and compounds.
How have the anticipated impacts of climate change been considered?
Two of the principles on which the design of green infrastructure in the city is based are functionality and resilience. In addition to creating recreational, safe and comfortable spaces for people, green and blue spaces provide ecosystem services that help mitigate climate change, adapt and improve resilience. For this, the following aspects are considered:
- Characterization of natural and anthropogenic hazards, as well as vulnerability and exposure, according to the “Atlas of Risks of Mexico City”.
- Incorporation of actions, techniques and/or practices that allow natural, social and economic systems to resist, assimilate, adapt and recover from the impacts and effects of global warming phenomena and disturbances caused by urban pressure.
- Linkage with climatic hazards and risks and the analysis of vulnerability traits by municipality.
- Integration of the basin approach in the rehabilitation, maintenance and comprehensive management of the city’s hydrological system, so as to contribute to water resilience.
On these bases, the interventions of the “Green Challenge” anticipate the expected impacts of climate change and seek to increase the recharge of the aquifer, reduce the risk of flooding, mitigate the urban heat island effect, recover and conserve the habitat of wild species (particularly those most vulnerable to climate change), increase the resilience of production systems inside conservation land and reduce the vulnerability of natural ecosystems.
What processes does the initiative include for it to be considerate in its use of soils and other natural resources?
Mexico City promotes a vision of circularity that is increasingly integrated into the production and consumption processes, which is reflected in the revegetation interventions that seek to reduce the extraction of natural resources, maintain a constant flow of these and manage them in a circularly way. Samples of this are:
- Production of substrates and soils from pruning and gardening residues to avoid the use of mountain land in nurseries, lawns, gardens and planters, parks and other green spaces, encouraging the continuity of nutrient flows and the regeneration of the soils.
- Creation of artificial wetlands, with benefits such as CO2 capture greater than forest surfaces, oxygen, temperature regulation, preservation of habitats for aquatic fauna, resident and migratory birds. The one designed in the form of a snail stands out within the San Juan de Aragón urban forest, of 3,100 m2 with a filtration capacity of 140,000 m3 in 24 hours.
- Use of rainwater through catchment systems, with the purpose of reducing the use of drinking water for domestic tasks and reducing the extraction of the aquifer, adding to the objectives of the revegetation strategy through another aspect.
- Greater treatment of wastewater, using only treated water in the maintenance of green areas and limiting the use of drinking water in activities for human consumption.
- Use of construction waste in rehabilitated spaces.
This has made it possible to print a comprehensive and circular vision of resources, which contributes to the regeneration of natural sources and the recovery of essential resources for biological cycles.
Monitoring, Maintenance, and Management
How has the initiative been designed and implemented so that long-term needs for management and maintenance are reduced and can be met?
The strengthening of the public policy framework and the integration of green infrastructure in urban planning instruments with a long-term vision were considered essential for the continuity and maintenance of interventions, for example:
- Mexico City developed the Special Program for Green Infrastructure, from which a multi-sector portfolio of short, medium, and long-term projects emerges.
- The strengthening of the Public Environmental Fund (administrated by the Secretariat of Environment of Mexico City and stablished by law) will make it possible to capitalize investment from sources of financing from multilateral, bilateral and private organizations, opening the opportunity to leverage greater resources for the maintenance of interventions and the execution of projects in the short, medium and long term.
- Strengthening the capacities of rural communities and social participation seeks to ensure ownership of projects and interventions and their continuity, despite administrative changes in the government. That is why one of the five components of Altépetl program named “Capacity building for rural well-being” is focused on develop technical, organizational and productive capacities in the beneficiaries of the program.
- To achieve plantations that imply fewer requirements and a more successful survival in the medium and long term, the aim has been to optimally combine the natural conditions offered in the rainy season with work during the dry season, the appropriate selection of species and permanent coordination between authorities in order to meet any requirement that may arise in terms of maintenance and needs of the vegetation.
What protocols are in place to facilitate monitoring of results?
The interventions carried out in the city are planned and evaluated through the combination of the following indicators:
- Structural indicators to monitor green infrastructure, the multidimensional diversity of the urban landscape and urban green spaces. They include:
- vegetation index by municipality
- green area index per capita
- – dex of accessibility to green areas
The latter has been essential to know that the average of green area per inhabitant (GA/Ihab) in 2017 was 7.54 m² (below international recommendations) and there was a notorious territorial inequality (six municipalities with GA/Ihab of 15.4 to 9.6m² and 10 municipalities with a GA/Ihab of less than 8.5 m² in their urban area or even less than 3 m2). The interventions have taken this condition into account to territorially balance the natural spaces.
- Ecological indicators to assess the biodiversity and ecological quality of the landscape:
- Margalef diversity index
- fragmentation index
- urban biodiversity index or Singapore index, due to end in mid-2022, with 28 indicators assessing native biodiversity, ecosystem services and governance
- Visual indicators to evaluate the visual landscape from surveys on the social perception of green infrastructure, biodiversity and environmental quality.
- Additionally, progress in the execution of the guiding programs and instruments (Special Green Infrastructure Program, Altépetl, Climate Action Program and soon the Strategy for the Conservation and Sustainable Use of Biodiversity) is measured.
How has the initiative been enhanced in response to monitoring of results?
The Special Green Infrastructure Program is a living and comprehensive instrument that can be adapted to the conditions of each city, because it combines the local visions and integrates government, academic and organizational efforts at all stages of its development, depending on the local needs expressed by all of them:
- Collaboration schemes with the private sector have been strengthened, as a result of requests from the members of the sector, to have increasingly homogeneous pre-designed proposals, which have allowed us to show more clearly the scope of the expected contributions, show a catalog of spaces and define financial estimates that provide greater certainty and enable a better assessment by companies.
- The support of the interventions with materials and actions of environmental awareness and education has been promoted even more, to cover the areas of opportunity identified by the field staff and the neighbors themselves, to generate an environmental awareness, care for the green areas that accompanies to interventions
- Green infrastructure solutions have been integrated transversally into multifunctional planning, management and urban design programs, projects and actions at various scales, in such a way that it has permeated more and more planning and execution instruments, in based on their own experiences and work with different areas of government.
This has allowed it possible to optimize resources, increase scope, improve coordination and increase the permanence of the actions carried out, for the regeneration of ecological conditions throughout the city.