Is fuelwood a sustainable source of energy for rural communities?

Two female villagers from Welverdiend, typical of the current profile of woodcutters, carry their day’s harvest home. Most of the wood collected will be used for cooking meals for the next two or three days (Picture by Dr Tony Swemmer) SAEON's field assistants Patrick Ndlovu and Mightyman Mashele measure trees in one of the permanent plots established near Welverdiend village (Picture by Dr Tony Swemmer) A recent survey around the village has revealed that an average of 3.6 wheelbarrow loads of wood are cut, per woodcutter, each week (Picture by Mitzi du Plessis)

Most rural communities in the bushveld regions of South Africa — and throughout Africa — rely on wood collected from communal lands surrounding their village for their household energy needs.

In addition to providing fuel for cooking, warmth and heating water, harvested wood is also used for building fences, walls and roofs.

However … can rural communities keep harvesting wood indefinitely? Can the supply of this valuable resource by rural ecosystems keep pace with the constant demand, particularly in the face of global climate change?

Widespread recognition of the importance of wood for sustaining the livelihoods of rural people led researchers to begin investigating the sustainability of wood harvesting many decades ago.

The general perception amongst ecologists and social ecologists has been that most rural ecosystems are degraded, and that a collapse of wood supply is imminent. However, the naturally occurring, indigenous trees that provide the wood have proven to be remarkably resilient, and seem capable of continually resprouting and growing new stems, even when cut year after year after year.

The collapse of wood supply predicted from studies conducted in the early 1990s has not materialised in rural areas in the central lowveld, but the potential for a collapse in the near future still remains, particularly with the advent of global climate change. Demand for firewood remains strong, despite the roll-out of electricity to most rural households. It is quite likely that the ecosystems in question are still in a process of responding to the cutting that has been occurring over the past decades, and will soon cross a threshold and enter a degraded state with much lower rates of wood production.

Furthermore, global climate change is likely to bring unprecedented heat waves and droughts, which may damage these ecosystems to the point that wood supply is permanently reduced. Understanding what determines the ability of rural ecosystems to produce wood therefore remains a key question in South African ecology.

In order to contribute to answering this question, the SAEON Ndlovu Node has initiated a long-term monitoring project at Welverdiend village, in a remote part of Mpumalanga bordering the Kruger National Park. Much of the pioneering research on wood harvesting was conducted in this area in the early 1990s. However, results of this work pertaining to sustainability were inconclusive, largely due to the challenge of determining supply rates.

Determining fuelwood supply and demand

Determining whether wood harvesting is sustainable at current rates, or at some point in the future, is simple if one knows the rates of supply and demand for wood. However, each of these two variables is highly complex, being determined by a range of interacting factors that vary through time. Demand depends on social factors such as the population size of a village, the income of the villagers, the cost of electricity, and even the structure of the population (which affects the number of people with the time and strength to go out and cut wood).

Supply depends on ecological factors such as rainfall, the status of the soil, the species of trees present around the village, the ability of the trees to reproduce (i.e. produce viable offspring) and the rate at which the trees have been cut in the past.

While previous studies have allowed for some estimate of the demand for wood in rural villages in South Africa, determining supply rates has yet to be done successfully. The most likely reason for this gap of knowledge is that researchers have been restricted to time-frames set by the availability of postgraduate funding. However, due to the long-term nature of SAEON, this new project will run for long enough to determine rates of wood supply under differing conditions of both climate and demand.

The research involves tagging individual trees to measure their growth rates and longevity, and the establishment of permanent monitoring plots to measure the number of trees cut in an area in a year.

In addition, some more socially oriented research has been conducted to establish who, where and why wood is cut. A recent survey around the village revealed that an average of 3.6 wheelbarrow loads of wood are cut, per woodcutter, each week. Consistent with other studies, over 80% of woodcutters have electricity at home, but choose to use wood for cooking to save money. Over 80% of the woodcutters are female, and ages range from 12 to 78 years. Repeating such sampling in future years will establish whether these profiles and patterns are changing, and elucidate trends in demand.

A matter of trust

Data for the project is being collected by the Ndlovu Node’s two field assistants, Patrick Ndlovu and Mightyman Mashele. Both grew up in Welverdiend, and are familiar with the languages spoken by local woodcutters, as well as the geography of the communal lands were the wood is harvested.

Their relationship with the local community is a major advantage for this type of research - they are trusted by local woodcutters who have not been afraid to answer their questions or allow them to record what and where they cut. A lack of such a relationship often hinders the progress of outside researchers when they attempt similar research in rural areas.