21 June 2016

Sustaining life and agriculture in the Peruvian desert

Kew scientist Oliver Whaley describes recent research in the Peruvian desert, working with large-scale farms to research, safeguard and restore plants.

By Oliver Whaley

Desert in Peru at dusk

Food from a 3,000 km greenhouse

As you push through supermarket aisles you might be surprised to find that your avocados, blueberries or Chilean wine comes from one of the oldest, driest and longest deserts in the world. Like it or not we are part of the global market, fuelling production from warm, tropical climates. Surprisingly, the efficiency of agricultural production and transport often means that imported food can be produced with low emissions whilst providing greatly needed jobs, and increasingly local environmental gains.

The Pacific seaboard of the Peru-Chile desert, with year-round sunshine, groundwater, minimal pests and sea-cooled air, ticks all of the boxes for superb growing conditions, making it ‘the largest greenhouse in the world’.  Yet the needs of burgeoning migrant populations from the Andes, and intensifying agriculture, have impacted the last relicts of native plants and agrobiodiversity (agricultural biodiversity). Here in Peru, native plants have allowed ancient desert cultures to thrive, and today they still have immense potential to solve many of our problems.

The mother of floods – brings life

Research suggests that when these benevolent desert forests are removed, agriculture becomes vulnerable to almighty periodic flooding across the Andean backbone which rises to the east.. Moisture is pushed seasonally to the west, over the Amazon to recharge coastal aquifers; but every 6–10 years it’s a different story: massive El Niño floods can bring revival to the desert, alongside widespread destruction. Herein lies the opportunity to conserve and utilise plants as an investment to sustain agriculture.

A dust devil rises out of the Ica valley into the Andean foothills, home to Nazca culture. Credit RBG Kew/O. Whaley.

Linking the supply-chain back to nature

Kew, in partnership with Sainsbury’s, has been working with large-scale farms (supplying global markets) in southern Peru, to research, safeguard and restore plants. Our ambitious target is to develop a working model for the integration of ecosystems (with their component biodiversity) into agro-industrial high-volume production landscapes – effectively working with nature where few other mechanisms exist to conserve, rebuild and, crucially now, to adapt. But of course, to be a replicable model the investment must have returns (or services) to agriculture such as water use reduction, pollination, carbon capture, erosion control, worker nutrition and wellbeing. Sainsbury’s is committed to these under their 20 by 20 Sustainability Plan and, building on 15 years of research and conservation in the arid coastal region of Peru, Kew is likewise committed.

People and cultural diversity are key to the protection of nature, especially here in the fragile desert where people cannot be separated from biodiversity, and in many cases provide protection to species though traditional agriculture and irrigation. But, scarily, a fast-declining number of smallholders clutch the last vestiges of agrobiodiversity, and still today produce a range of traditional ‘huerta’ fruits to make an essential contribution to migrant worker family nutrition.

 

Collage of plants in the Andes
Flora from the arid W. slopes, S. Andes. Top row: cactus Corryocactus brevistylus, E. giganteum, T. fulva. Bottom: E. lunatus, H. arequipensis, P. guajava. Credit RBG Kew/O. Whaley.

Conservation through use

Our second key focus is conservation of rare ‘huerta’ varieties, some of which have been domesticated and selected for over the last 8,000 years of cultural ‘boom’, culminating in the Nazca and Moche cultures.

These include nitrogen-fixing trees such as Acacia species, Pacay (Inga feuillei), and Huarango (Prosopis spp.) which have sustained soil fertility for millennia, allowing the production and breeding of coloured cottons (Gossypium barbadense), maize (Zea mays), Lima beans (Phaseolus lunatus), lucuma (Pouteria lucuma), guava (Psidium guajava) and guanabana (Annona muricata).

Having researched, mapped and selected these threatened varieties, we employed the simple idea of ‘conservation through use’ by integrating into schools and communities, whilst helping to develop products from native trees such as Huarango, to engender cultural protection.

Traditional agriculture is not yet widely seen as a provider of services to high-volume global agriculture. Our research has shown that native pollinator bees, which inhabit traditional agricultural land, pollinate much more efficiently than introduced and costly honey bees. Likewise, traditional management of soil fertility has taught us how to rebuild this precious resource. Our reforestation areas are building leaf litter layers at a rate of 2–4 cm per year.

Image left of Peruvian lady planting. Right: Kew researcher in front of a poster
Left: Planting ancient pacay varieties in the project huerta del bosque mágico de los niños de Santa Cruz. Right: At the Project Huarango Festival, a Kew team volunteer explains about the poorly known Tillandsi. Credit RBG Kew/O. Whaley.

Plant-rescue and research centre

A challenge of field-research in agriculture is that in situ land and facilities are needed. After two year’s support from Sainsbury’s in close collaboration with Barfoots UK, and agroindustries in Peru (Agrícola Chapi and Agrokasa), we have established the first Native Plant Research and Conservation Centre. Within the security of agroindustry, the facility is developing native seed management and propagation protocols for rare native plants at large scale, and is currently acting as a training hub and a much-needed community resource.

 

Photos of the Native Plant Research and Conservation Centre in Peru.
The Native Plant Research and Conservation Centre is dedicated to schools and the local community, providing native plants and training. Credit RBG Kew/O. Whaley.

Re-establishing connections

Desert flora often form corridors that follow water sources; in Peru these corridors connect the coast to the Andes. In order to replicate essential gene-flow highways, where seasonal streams have been removed, we are developing techniques to establish corridors and low-water hedges throughout the agroindustry. The corridors aid biodiversity but also provide multiple ecosystem services; monitoring each month allows us to develop the best irrigation and planting techniques. Additionally, the use of drones and imaging technology is a vital tool to inform the real work on the ground.

Most watersheds in the western Andes are substantially degraded, even lacking the seed for natural regeneration. As such, we have added seed pellets to replenish the soil seed bank in preparation for the next El Niño flood.

 

Six images of trees and landscape taken by a drone
Drone imaging and red-edge sensors are used to monitor tree health in restoration and relicts. Credit RBG Kew/O.Whaley.

No plant is an island

Together with a wonderfully enthusiastic and committed team of student volunteers, we are making exciting discoveries about our reforestation under comparable irrigation regimes. The habitat restoration corridors are colonised by wild guinea pigs (Cavia tschudii), lizard species and desert foxes that actually help to ‘replant’ and extend the forest by burying and dispersing seeds.

The challenge now is to find the balance between habitat state and intensive food production where, for example, there are enough insectivorous birds (such as tanagers, woodpeckers, hummingbirds and nightjars, which have colonised our reforestation trials) to be able to control insect pests, but there are also enough raptors to discourage the flocks of parakeets that cause damage to grapes.

We have recorded 22 breeding species and over 50 bird species in one of our restored habitats, including most recently, our project flagship species, the threatened slender-billed finch (Xenospingus concolor).

To have any lasting impact, regional knowledge sharing has been key. Seeds are sown in the minds as well as the ground. The project is producing a series of research publications and a new guide on useful woody plants of coastal Peru and Chile. Knowledge is also shared via our local project website in Peru, and our Plants and Vegetation book is used today in the local curriculum. The ongoing Huarango Festival established by our previous projects in the region, continues to foster a local culture of ‘stitching the sky back to the land’.

Images of Peruvian guinea pig, a fox, lizard and snake
Peruvian desert fauna photographed in our reforestation corridor in agroindustry: montane guinea pig, Andean fox, desert tegu Culebra de la costa. Credit RBG Kew/O.Whaley.

References

Beresford-Jones, D.G., Torres, S.A., Whaley, O.Q. & Chepstow-Lusty, A.J. (2009). The role of Prosopis in ecological and landscape change in the Samaca basin, lower Ica Valley, south coast Peru from the early horizon to the late intermediate period. Latin American Antiquity 20(2): 303–332. Available online

Beresford-Jones, D.G., Whaley, O., Ledesma, C.A. & Cadwallader, L. (2011). Two millennia of changes in human ecology: archaeobotanical and invertebrate records from the lower Ica valley, south coast Peru. Vegetation History and Archaeobotany 20(4): 273–292. Available online

Beresford-Jones, D., Pullen, A.G., Whaley, O.Q., Moat, J., Chauca, G., Cadwallader, L., Arce, S., Orellana, A., Alarcón, C., Gorriti, M. & Maita, P.K. (2015). Re-evaluating the resource potential of lomas fog oasis environments for Preceramic hunter–gatherers under past ENSO modes on the south coast of Peru. Quaternary Science Reviews 129: 196–215. Available online

Garibaldi, L.A., Steffan-Dewenter, I., Winfree, R., Aizen, M.A., Bommarco, R., Cunningham, S.A., Kremen, C., Carvalheiro, L.G., Harder, L.D., Afik, O. & Bartomeus, I. (2013). Wild pollinators enhance fruit set of crops regardless of honey bee abundance. Science 339 (6127). Available online

Whaley, O.Q., Orellana, A., Pérez, E., Tenorio, M., Quinteros, F., Mendoza, M. & Pecho, O. (2011). Plantas y Vegetación de Ica, Perú - Un recurso para su restauración y conservación. Royal Botanic Gardens, Kew.

Whaley, O.Q., Beresford-Jones, D.G., Milliken, W., Orellana, A., Smyk, A. & Leguía, J. (2010). An ecosystem approach to restoration and sustainable management of dry forest in southern Peru. Kew Bulletin 65(4): 613–641. Available online

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