Restoring & Conserving High-Andean Grasslands for Water
Summary
Punas, the spongy grasslands native to Peru's high-Andean region, are an essential part of the region's water cycle. Restoring and conserving these grasslands can play an important role in enhancing the water supply for the city of Lima, especially during the dry season.
Lima, the world's second-largest desert city, relies on a combination of limited seasonal surface water, alluvial aquifers, and interbasin transfers to provide water to its many inhabitants (Hommes & Boelens, 2017 ; Lerner et al., 1982; Mark, 2015; Ritter, 2018). The city is rapidly expanding and its population booming, factors that additionally complicate the future water security of its 10 million inhabitants.
Intervention
To address water scarcity across the country, SUNASS (Superintendencia Nacional de Servicios y Saneamiento, Peru's national water regulator) incentivizes and supports public water service providers to seek out nature-based solutions to complement the typical engineering solutions that utilities use in water supply systems (Forest Trends, 2020). The national Compensation Mechanisms for Ecosystem Services Law (2014) serves as a legal framework for these efforts and defines permissible nature-based interventions (Forest Trends, 2020). Furthermore, SUNASS regulated a special water tariff to serve as funding for these nature-based solutions. Lima's water utility, SEDAPAL (Servicio de Agua Potable y Alcantarillado de Lima ), was one of the participating water utilities that committed to deploying nature-based interventions to enhance its water supply (Forest Trends, 2020).
Global focus on the likely exacerbation of water scarcity by climate change, both in Lima and elsewhere, likely influenced SEDAPAL's decision to take action to ensure a more sustainable future water supply. Furthermore, Lima's water supply is highly variable, making it challenging for the megacity to ensure consistent water supply year-round. In the dry season (May to November), droughts are common and river flows are low; during the rainy season (December to March), river levels spike significantly (Gammie, de Bievre & Guevara, 2015). As such, Lima experiences large water deficits during its dry season and water surpluses during its rainy season.
Punas , spongy grasslands native to Peru's high-Andean region, are an essential part of the region's water cycle and can play an important role in enhancing the water supply for the city of Lima, especially during the dry season (Gammie, de Bievre & Guevara, 2015). Grasslands serve as "natural water factories", absorbing huge amounts of water and releasing it slowly throughout the dry season, thereby playing a key role in maintaining a region's hydrological balance (Jankowska-Huflejt, 2006). Peruvian punas are typically used for cattle and alpaca grazing by local communities (Gammie, de Bievre & Guevara, 2015). While alpacas have a relatively small impact on the hydrological properties of the grasslands' soils (due to their cushioned feet and cutting bite), heavier cattle compact the soil, cause soil creep, and potentially reduce overall grass coverage. As such, grazing and cattle-related activities are considered the primary cause of the degradation of Peru's punas (Gammie, de Bievre & Guevara, 2015).
Two main interventions have been designed to restore and conserve the natural Andean puna grasslands' beneficial hydrological properties: animal exclusion and rotational grazing (Gammie, de Bievre & Guevara, 2015). Animal exclusion from natural grasslands is achieved primarily by designating protected zones from which animals are prohibited. This exclusion allows compacted soils to decompress, improves soil bulk density and infiltration capacity, and provides the opportunity for vegetation to return (Gammie, de Bievre & Guevara, 2015). Allowing the puna ecosystem to recover results in the restoration of the grasslands' positive hydrological qualities, ultimately improving hydrological capacity both at the site and watershed levels (Gammie, de Bievre & Guevara, 2015). Rotational grazing on natural grasslands is a variation of the animal exclusion intervention, which entails a transition from year-round intensive grazing to periodic grazing defined by periods of animal exclusion, allowing the grasslands to recover (Gammie, de Bievre & Guevara, 2015). Animal exclusion from the grasslands is implemented and enforced through several interventions, including closure of the grasslands, removal of current grazers, construction of physical barriers to grasslands, and community governance measures (Gammie, de Bievre & Guevara, 2015).
In 2015, SEDAPAL approved the largest financial commitment for green infrastructure investment of any country in Latin America, announcing a $112 million investment in green infrastructure projects in and around Lima (Kenny, 2015). The $112 million investment is secured from municipal water services revenue and amounts to 5% of the total monthly water fees that are regularly collected by SEDAPAL (Kenny, 2015; Zwick, 2015). The investment is intended to go towards programs designed to help the Andes adapt to climate change and improve water quality (Kenny, 2015). Of this, $26 million has been committed to "green infrastructure" programs specifically, including the restoration and conservation of high-Andean grasslands (Kenny, 2015). An additional $2.9 million in funding for the restoration of the punas was secured from the US Agency for International Development (USAID), as well as funding from GORE Ancash (the regional government of Ancash) and the national Ministry of Agriculture (USAID, 2018). The puna conservation and restoration project was implemented by a consortium of institutions, including the Mountain Institute, Canadian-funded Forest Trends, and USAID.
Challenges
Restoring Peru’s puna grasslands faces challenges such as enforcing grazing restrictions and securing long-term funding. Balancing local livelihoods with environmental goals is difficult, especially with cattle grazing pressure. Climate change could affect the puna’s hydrological benefits, and large-scale implementation requires coordination among government, communities, and NGOs.
Outcomes
The animal exclusion from grasslands can be implemented on a total of 12,121 hectares of land and in 50 communities, while rotational grazing can be implemented on 28,283 hectares of land and in 50 communities (Gammie, de Bievre & Guevara, 2015). These combined initiatives would yield an estimated 1.44 m3/s to baseflow: equivalent to 30.4 million m3 of water during the dry season (Gammie, de Bievre & Guevara, 2015). If implemented at their full potential scale, the two puna restoration interventions would cost approximately 10.15 million USD/m3/s per unit of increased baseflow (Gammie, de Bievre & Guevara, 2015). Additionally, if implemented at full scale, the puna restoration and conservation efforts would reap significant benefits relative to cost. Ultimately, restoring and conserving the Andes' natural grasslands could positively impact Lima's water security and help build the megacity's future resilience to drought and water stress.
References
Restoring & Conserving High-Andean Grasslands for Water
Summary
Punas, the spongy grasslands native to Peru's high-Andean region, are an essential part of the region's water cycle. Restoring and conserving these grasslands can play an important role in enhancing the water supply for the city of Lima, especially during the dry season.
Lima, the world's second-largest desert city, relies on a combination of limited seasonal surface water, alluvial aquifers, and interbasin transfers to provide water to its many inhabitants (Hommes & Boelens, 2017 ; Lerner et al., 1982; Mark, 2015; Ritter, 2018). The city is rapidly expanding and its population booming, factors that additionally complicate the future water security of its 10 million inhabitants.
Issue
Intervention
To address water scarcity across the country, SUNASS (Superintendencia Nacional de Servicios y Saneamiento, Peru's national water regulator) incentivizes and supports public water service providers to seek out nature-based solutions to complement the typical engineering solutions that utilities use in water supply systems (Forest Trends, 2020). The national Compensation Mechanisms for Ecosystem Services Law (2014) serves as a legal framework for these efforts and defines permissible nature-based interventions (Forest Trends, 2020). Furthermore, SUNASS regulated a special water tariff to serve as funding for these nature-based solutions. Lima's water utility, SEDAPAL (Servicio de Agua Potable y Alcantarillado de Lima ), was one of the participating water utilities that committed to deploying nature-based interventions to enhance its water supply (Forest Trends, 2020).
Global focus on the likely exacerbation of water scarcity by climate change, both in Lima and elsewhere, likely influenced SEDAPAL's decision to take action to ensure a more sustainable future water supply. Furthermore, Lima's water supply is highly variable, making it challenging for the megacity to ensure consistent water supply year-round. In the dry season (May to November), droughts are common and river flows are low; during the rainy season (December to March), river levels spike significantly (Gammie, de Bievre & Guevara, 2015). As such, Lima experiences large water deficits during its dry season and water surpluses during its rainy season.
Punas , spongy grasslands native to Peru's high-Andean region, are an essential part of the region's water cycle and can play an important role in enhancing the water supply for the city of Lima, especially during the dry season (Gammie, de Bievre & Guevara, 2015). Grasslands serve as "natural water factories", absorbing huge amounts of water and releasing it slowly throughout the dry season, thereby playing a key role in maintaining a region's hydrological balance (Jankowska-Huflejt, 2006). Peruvian punas are typically used for cattle and alpaca grazing by local communities (Gammie, de Bievre & Guevara, 2015). While alpacas have a relatively small impact on the hydrological properties of the grasslands' soils (due to their cushioned feet and cutting bite), heavier cattle compact the soil, cause soil creep, and potentially reduce overall grass coverage. As such, grazing and cattle-related activities are considered the primary cause of the degradation of Peru's punas (Gammie, de Bievre & Guevara, 2015).
Two main interventions have been designed to restore and conserve the natural Andean puna grasslands' beneficial hydrological properties: animal exclusion and rotational grazing (Gammie, de Bievre & Guevara, 2015). Animal exclusion from natural grasslands is achieved primarily by designating protected zones from which animals are prohibited. This exclusion allows compacted soils to decompress, improves soil bulk density and infiltration capacity, and provides the opportunity for vegetation to return (Gammie, de Bievre & Guevara, 2015). Allowing the puna ecosystem to recover results in the restoration of the grasslands' positive hydrological qualities, ultimately improving hydrological capacity both at the site and watershed levels (Gammie, de Bievre & Guevara, 2015). Rotational grazing on natural grasslands is a variation of the animal exclusion intervention, which entails a transition from year-round intensive grazing to periodic grazing defined by periods of animal exclusion, allowing the grasslands to recover (Gammie, de Bievre & Guevara, 2015). Animal exclusion from the grasslands is implemented and enforced through several interventions, including closure of the grasslands, removal of current grazers, construction of physical barriers to grasslands, and community governance measures (Gammie, de Bievre & Guevara, 2015).
In 2015, SEDAPAL approved the largest financial commitment for green infrastructure investment of any country in Latin America, announcing a $112 million investment in green infrastructure projects in and around Lima (Kenny, 2015). The $112 million investment is secured from municipal water services revenue and amounts to 5% of the total monthly water fees that are regularly collected by SEDAPAL (Kenny, 2015; Zwick, 2015). The investment is intended to go towards programs designed to help the Andes adapt to climate change and improve water quality (Kenny, 2015). Of this, $26 million has been committed to "green infrastructure" programs specifically, including the restoration and conservation of high-Andean grasslands (Kenny, 2015). An additional $2.9 million in funding for the restoration of the punas was secured from the US Agency for International Development (USAID), as well as funding from GORE Ancash (the regional government of Ancash) and the national Ministry of Agriculture (USAID, 2018). The puna conservation and restoration project was implemented by a consortium of institutions, including the Mountain Institute, Canadian-funded Forest Trends, and USAID.
Challenges
Restoring Peru’s puna grasslands faces challenges such as enforcing grazing restrictions and securing long-term funding. Balancing local livelihoods with environmental goals is difficult, especially with cattle grazing pressure. Climate change could affect the puna’s hydrological benefits, and large-scale implementation requires coordination among government, communities, and NGOs.
Outcomes
The animal exclusion from grasslands can be implemented on a total of 12,121 hectares of land and in 50 communities, while rotational grazing can be implemented on 28,283 hectares of land and in 50 communities (Gammie, de Bievre & Guevara, 2015). These combined initiatives would yield an estimated 1.44 m3/s to baseflow: equivalent to 30.4 million m3 of water during the dry season (Gammie, de Bievre & Guevara, 2015). If implemented at their full potential scale, the two puna restoration interventions would cost approximately 10.15 million USD/m3/s per unit of increased baseflow (Gammie, de Bievre & Guevara, 2015). Additionally, if implemented at full scale, the puna restoration and conservation efforts would reap significant benefits relative to cost. Ultimately, restoring and conserving the Andes' natural grasslands could positively impact Lima's water security and help build the megacity's future resilience to drought and water stress.
Issues |
|---|
Water Scarcity and Access |
Solutions |
|---|
Sustainable Water Supply & Climate Solutions |
References
Forest Trends. (2020, February 06). Connecting Indigenous Knowledge and Scientific Research for Improved Water Security. Retrieved July 28, 2020, from https://www.forest-trends.org/blog/how-to-connect-indigenous-knowledge-and-scientific-research-for-greater-water-security/
Gammie, G., De Bievre, B., & Guevara, O. (2015). Assessing green interventions for the water supply of Lima, Peru. Forest Trends.
Hommes, L., & Boelens, R. (2017). Urbanizing rural waters: Rural-urban water transfers and the reconfiguration of hydrosocial territories in Lima. Political Geography, 57, 71-80.
Jankowska-Huflejt, H. (2006). The function of permanent grasslands in water resources protection. Journal of Water and Land Development, 10(1), 55-65.
Kenny, A. (2015, November 17). Inside Peru’s Coming Green Water Revolution. Retrieved July 28, 2020, from https://www.ecosystemmarketplace.com/articles/inside-perus-coming-green-water-revolution-2/
Lerner, D. N., Mansell-Moullin, M., Dellow, D.J., Lloyd, J.W. (1982). Groundwater studies for Lima, Peru.
Mark, A. (2015, April 16). Lima to restore pre-Incan aqueducts to alleviate its water crisis. Retrieved July 28, 2020, from https://news.mongabay.com/2015/04/lima-to-restore-pre-incan-aqueducts-to-alleviate-its-water-crisis/
Ritter, K. (2018, June 28). Water Access In Lima Complicated by Inequality and Climate Uncertainty. Retrieved July 28, 2020, from https://www.circleofblue.org/2018/south-america/water-access-in-lima-complicated-by-inequality-and-climate-uncertainty/
Zwick, S. (2015, April 30). Lima To Invest $110 Million in Green Infrastructure And Climate Adaptation. Retrieved July 28, 2020, from https://www.ecosystemmarketplace.com/articles/lima-to-invest-110-million-in-green-infrastructure-and-climate-adaptation/