Indigenous People and the Rainforest of South America

A key issue today in the management of rainforest biodiversity is whether or not there is a place for human populations within the boundaries of nature preserves. Strict preservationists see no place for humans within preserves, arguing that any human involvement is detrimental to the natural functioning of ecosystems. Conservationists, on the other hand, vary in the way they would answer. Some envision a plan that sets aside land for preservation, in the strict sense, along with some areas designated as lands for indigenous peoples. Others argue that indigenous peoples should be able, and indeed have the right, to live in land set aside for forest conservation, arguing that they are the best managers of rainforest biodiversity.

As succinctly as possible, answer the following question(s): As there a place for ‘traditional’ indigenous farming and hunting systems in forest preserves? In your answer, use the following points as an outline. What system of farming might be used in a rainforest? Describe in detail, the steps involved in this kind of farming, and importantly how/why it works. How do indigenous peoples integrate the acquisition of animal protein into this system? From an ecological perspective, when and why might this system be adaptive (i.e., it is ecologically viable) and when and why might this system become maladaptive(i.e., it is not, or has little, ecological viability)? Do indigenous people play a role in the creation of diversity, and if so, why, or if not, why not?

Although some preservationists and conservationists may argue that in order to protect the rainforests there is no place for indigenous peoples within the boundaries of nature preserves, suggesting that any human activity in these areas would be harmful to the natural environment. Although such reckoning might be the case in regards to contemporary models of agriculture in the forests this reasoning does not apply to ‘traditional’ indigenous subsistence practices which carefully manage the forests through various methods, applying generations of indigenous knowledge to earn a living without ever damaging the fragile ecosystem. Therefore, not only is there a place for indigenous people within the forest, they also enhance its preservation whilst adding diversity to existing ecosystem arguably making them best managers of rainforest biodiversity.

The ‘traditional’ subsistence practice employed by the indigenous peoples who inhabit the rainforests of the Amazon Basin, namely agroforesty, is highly adaptive to the unique environment. History shows that it is remarkably sustainable since it has been the main form of subsistence for the indigenous people of the area for centuries, if not longer, while never having depleted the forests of their valuable resources. Agroforestry, the method used by many indigenous peoples within the tropical forests, is classified as a land management technique which combines naturally existing trees and plants with crops or grazing and incorporates numerous steps over an extended period of time. First, small plots or gardens are cleared often using machetes, then if the environment is suitable a practice known as ‘slash and burn’ agriculture is employed. ‘Slash’ refers to the actual clearing of the garden, the ‘burn’ to the carefully managed fires which are used to remove the remaining shrubbery. The remnants of the fire will constitute highly valuable fertilizer thus adding greatly needed minerals to the poor soils. What is key however is that many key pre-existing plants and trees are kept rather than being removed; these trees will then be carefully cultivated and incorporated into the garden in a practice known as arboriculture.

A hallmark of this pattern of subsistence is the polycultural nature of the gardens; the indigenous people rely on a great variety of plants and the gardens are never dominated by a single species while existing plants and trees are carefully maintained. The immense richness of these gardens mimics the natural diversity of the forests. Within agroforesty there is a focus on shifting cultivation meaning that the gardens pass through various stages throughout their life cycle. When the garden is first cleared, farmers plant high nutrient demanding crops such as corn, whereas in the later stages of the garden they transition to crops like manioc which survive well in the lesser quality soils. These later crops and are also often shade tolerant, adapting well to the later stages as the forest reclaims the garden and the canopy begins to grow back. Since tropical rainforest systems are so fragile and the vegetation relies on a very thin and poor soil base, this method of subsistence means that the already existing natural ecosystem is not destroyed but instead crops, valuable wild resources and animals are all carefully maintained. These sunlit, open gardens also attract animal protein which indigenous people are able to hunt and set traps to catch as well as finishing in the local rivers to supplement their diet.

From an ecological perspective agroforestry is certainty adaptive to the unique and harsh conditions of the forest environment. The tropical rainforests tend to be characterised by poor quality lateralized soils as a result of direct sunlight and high year round temperatures breaking down the important mineral components of the soils, which are then washed away by the heavy and frequent rains. This process results in highly leached soils which are agriculturally very poor, with around 82% of the usable terra fimre ground being made up of these poor lateralized ultisoils and oxisoils. Due to the low quality soils contemporary agriculture does not work and is maladaptive within the forest since it depletes the already fragile lateralized soils of their remaining minerals very quickly therefore requiring the framer to find new land frequently.

The forest vegetation has adapted to this harsh environment by employing a closed nutrient cycle; taking what it needs without ever depleting the soils, an adaptation is also true of indigenous farming models. Agroforesty is adaptive since it builds on the forest, keeping integral features such as the canopy so as not to undermine the fragile ecosystem. Slash and burn agriculture also adds much needed nutrients to the soils and the practice of shifting cultivation means that crops are rarely planted in the same soil for more than 3 years therefore making sure that the soils are never exhausted. In addition to creating more diversity and protecting the forest, ‘traditional’ models of agriculture are also highly sustainable since they do not exhaust either the soils or the forest products. The long fallow periods that characterise this type of agriculture are highly recuperative allowing for the eventual re-growth of the forest with no lasting damage. Furthermore, the gardens are never truly abandoned; farmers continue to return to fallow gardens as there are still many valuable items to be collected and importantly, this way of life only requires the indigenous communities to have to move the settlement every several decades in search of new land. In short, indigenous people have shown that people and nature can co-exist sustainability and also that what people see as natural forest has in fact been managed by humans for centuries.

However, although this system has sustained the indigenous peoples of the rainforests for much time, it requires specific conditions in order to function. Vast amounts of land are required to sustain indigenous models of agriculture and the practice of Agroforestry. Such systems could become maladaptive if populations become too high and there is not enough land to support them. This would of course be the case within nature reserves since they are comprised of a limited amount of space. In this case resources would fast become depleted, particularly large game and fields would have to be reused without allowing them to go fallow, resulting in lower yields for harder work.

Diversity is key to the rainforest’s survival, high demanding mono-crops would strip the soil of its valuable nutrients. Instead the forest employs a closed nutrient cycle where a diversity plants are highly dependent on each other for nutrients. The tropical rainforest are some of the most diverse places on earth, home to an incredible array of plant and animal species that can be found nowhere else. Unfortunately, due to loss of habitat these species are in danger extinction and the unique diversity is being lost; since the time of European contact over 90% of the original tropical forest have been destroyed. The incredible biodiversity of the rainforests needs to be protected as it is threatened by contemporary mono-crop agriculture which clears the forest of its trees in order to create fields. Indigenous people play a vitally important role in the creation on diversity within tropical rainforests. Their ‘traditional’ system of agroforesty creates more diversity by building on the already existing features of the rainforest; adding new plants whilst maintaining and caring for exiting plants and trees yet never depleting the resources. At the end of the carefully managed process of agroforesty the forest will eventually grow back reclaiming the gardens, creating more diversity without leaving lasting damage.

Shannon Turner-Riley

ANTH 391: Indigenous People of the Amazon
Instructor: Dr. Peter Stahl
Tuesday 11^th October, 2011