We flew to Quito after a crazy whirlwind of packing and goodbyes and (in my case) a raging flu-fueled fever that turned the last week into a glaze of weird dreams and missed deadlines. Just two days to adapt to the head-in-the-clouds elevation of the city (2600 m / 9200 ft), and we were already climbing higher, to the soaring Andean highlands that hold the key to water and life in the mountain tropics: the páramo.
This rich ecosystem is subject to soaring temperature variation, with warm beautiful days and frozen nights: a "summer by day and winter by night" environment. The life-forms that have evolved to survive in this climate are hardy, durable, capable of enduring incredible swings in temperature. Pampas grasses (above) grow in clumps that are 80% dead material: this shields the living material, creating a buffer against the cold when the night temperatures plummet. Another survival mechanism is seen in cushion plants (below): these species form large mounds of vegetation, where only the outermost is living: everything inside is dead matter, slowly decaying - and as the material decomposes, as in any good compost pile, it generates heat. This keeps the outermost living layer warmer than the ambient nighttime temperature.
Kick-ass adaptations to an extraordinarily harsh environment? Yes ma'am.
Perhaps the coolest thing about cushion plants, as a note, is that they exhibit an extraordinary amount of cooperation between species. The cushions can be formed by five or six separate species, all co-existing in the same mound (below), and all benefiting equally from the warmth generated inside their communal compost heating system. The vicious competition frequently described in rainforest systems does not apply here at elevation: survival is so difficult, given the wild swings in temperature, that it is not worth the risk to compete here. The best and most successful way for these plants to survive is to share their space.
The páramo is not just a pretty face, however. It plays a vital role in the provision of water to Andean cities like Quito and Bogotá. The huge amount of organic material stored in the soil absorbs and stores water from rain and snowmelt, making it an expansive and reliable source of clean, pure water. Quito draws its water directly from two páramos, Papallacta and Antisana, where vast reservoirs hold enough water to supply the city's growing needs.
But there are threats to the páramo, which we learned about and saw first-hand on our visits. It has been used extensively for cattle-grazing, which often involves burning away the dead material of the pampas grasses, and for growing plantations of pine or eucalyptus for wood. Studies show that these land uses are devastating for the water storage capacity of the páramo. For one thing, removing the low-lying grass and shrub vegetation means that water will run off rather than soak into the ground, contributing to the erosion of páramo soils; for another, burning or over-trampling by cattle can compact the soil and reduce its porosity - in other words, its capacity to hold water.
These threats raise an important question: what is the value of maintaining the ability of the páramo to supply water? In other words, what is the value of keeping the páramo in a healthy and pristine state, so that it can continue to supply water to Quito's growing population? When we ask these kinds of questions, we are talking about the idea of "Ecosystem Services" - the services and functions that ecosystems provide to humans. When we talk about an ecosystem in terms of the services it provides us, we can start to place a dollar value on it - a controversial practice at best.
Walking through the páramo landscape, with its stunning rolling hills and its lakes in every valley, it is easy to feel that this landscape should be conserved just for its sheer beauty. But the reality is that we live in a world that has been heavily impacted by a rapidly growing human population, and conservation for the sake of conservation is not always a viable option. So in this situation, where cattle grazing and plantations are creeping further and further into the páramo landscapes, maybe the strongest argument for conservation can be made by comparing the value of a pristine acre of páramo, with its water provisioning capacity at full, to the value of a burned and trampled acre that has completely lost the ability to retain or supply water.
The time spent in the páramo was other-worldly, lent an air of stillness and exhilaration by the elegant sweep of landscape falling away to every side. Sat amidst the clouds at over 3000 m (~ 10,000 ft), it seems to govern this kingdom of the tropics: a stately and regal royal whose duty it is to ensure no-one goes thirsty. I felt a sense of wistfulness descending back into the forest, which feels chaotic in comparison. But that lasted only for a moment, because, well, the Amazon Rainforest. Next post.
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