SOS Forests

Biochar Is a Sidetrack

I attended an interesting mini-conference on “biomass” yesterday. All the speakers were engaging. One of the topics discussed was biochar, charcoal incorporated into soils.

Charcoal has been identified as an important soil constituent in anthropogenic enriched dark soil (Amazonian dark earths or terra preta) found throughout the Amazon Basin.

Biochar is a valuable soil amendment in heavily leached soils because carbon binds to and stores the metallic oxide nutrients essential to plant growth. The addition of charcoal as well as organic detritus and “night soil” to Amazonian lateritic soils helped to create and sustain terra preta over centuries.

But singular additions of biochar to soils do not have much effect, even to very poor and weathered soils [here]. Incorporating compost and wood ash is more beneficial. That was the strategy of the ancient indigenes who created terra preta. Charcoal was not necessarily the key ingredient. Further, biochar is a very expensive soil amendment [here]. It is far cheaper and more effective (at increasing soil productivity) to apply manure straight, rather than to cook the manure in ovens first.

Nor is biochar the solution to global warming. The globe is not warming, CO2 is not a significant driver of global temperatures, and biochar is not made from fossil fuels. Biochar is a part of the natural, organic, carbon cycle. There will never be enough man-made biochar produced to make a detectable difference in atmospheric CO2.

Terra preta has other charms, though. The most significant finding from terra preta research is the reconstruction of human history. Historical human influences over millennia have dramatically altered the landscapes and vegetation in Amazonia and on every continent save Antarctica.

The landmark book on terra preta is:

William I. Woods, Wenceslau G. Teixeira, Johannes Lehmann, Christoph Steiner, Antoinette M.G.A. WinklerPrins, Lilian Rebellato (eds.) 2009. Amazonian Dark Earths: Wim Sombroek’s Vision [here].

Amazonian dark earths are carbon-rich soils developed by ancient civilizations in what was once thought to be a pristine wilderness. Dedicated to Dutch soil scientist Wim Sombroek (1934-2003) who was the first modern investigator of terra preta, Amazonian Dark Earths: Wim Sombroek’s Vision is a compilation of the latest, cutting-edge studies in this fascinating and important multi-disciplinary field.

In another reference (Michael J. Heckenberger, J. Christian Russell, Joshua R. Toney, and Morgan J. Schmidt. 2007. The legacy of cultural landscapes in the Brazilian Amazon: implications for biodiversity) [here] the authors summarize:

For centuries Amazonia has held the Western scientific and popular imagination as a primordial forest, only minimally impacted by small, simple and dispersed groups that inhabit the region. Studies in historical ecology refute this view. Rather than pristine tropical forest, some areas are better viewed as constructed or ‘domesticated’ landscapes, dramatically altered by indigenous groups in the past. This paper reviews recent archaeological research in several areas along the Amazon River with evidence of large pre-European (ca 400–500 calendar years before the present) occupations and large-scale transformations of forest and wetland environments.

Rather than a pristine, untrammeled, unoccupied wilderness, Amazonia has been home to people for thousands of years. The residents were agriculturalists who modified soils in order to grow corn (maize), squash, beans, fruiting palms, gourds, pineapples, cotton, arrowroot, and many other cultivated fruits, nuts, tubers, and fibers.

There is no such thing as pristine wilderness. “Wilderness” is a modern conceit, a Euro-centric myth without foundation in the real world, grounded in ignorance and cultural bigotry. Wilderness designation leads to abandonment of stewardship and the subsequent destruction of history and heritage as well as natural resources.

The wilderness myth is rooted in conquest and genocide, reinforced by nineteenth-century romanticism. The only thing wilderness designation protects is cultural delusion.

A far better approach to our heritage landscapes would be realization and study of the ancient human-environment relationships and a renewed commitment to stewardship. Instead of abandonment of our landscapes to ignorance and holocaust, perhaps we could begin to intelligently care for our forests, savannas, and prairies once again. After all, human beings have been the caretakers of this planet for thousands of years. We need to understand and accept our heritage and concomitant responsibilities.

The great and much appreciated Australian forester, Roger Underwood, states succinctly the real purposes of forest stewardship [here]:

Finally, I urge foresters to oppose single-purpose forestry, the so-called “conservation plantations”, so beloved of environmentalists and academics. Quite frankly, I find the concept of growing tree plantations for the sole purpose of providing a carbon sink to be ridiculous and an insult to our profession and to the community. These conservation plantations are both an illusion and a contradiction. In the first place they are based on the assumption that forests in Australia do not suffer bushfires. Secondly, the concept ignores the fact that timber harvested from sustainably-managed plantations provides an industrial substitute for steel, aluminium and concrete, all of which are environmentally unfriendly in every respect, including the massive outpouring of carbon dioxide during their manufacture, the priority worry of those concerned about global warming.

No forester should need to be reminded that well-managed forests can provide a full range of benefits — everything from timber to catchment protection, to biodiversity, to recreation and carbon capture. But it is not enough to just know this. We should be standing up and fighting for it, not meekly allowing the moneymen, academics and environmentalists who are taking the community down a primrose path with their concept of single-use ‘conservation plantations’.

Roger Underwood’s words should be taken to heart, not just by foresters but by all who understand that forests provide a suite of values.