'Formiguers', a historical system of soil fertilization (and biochar production?)

Abstract ‘Formiguers’ are structures similar to charcoal-kilns that were used to burn piles of biomass with a soil cover in order to produce fertilizers for agricultural plots. Their use was widespread in Spain up to the 1960s and similar structures are still in use in India and Bhutan. Our objective was to study the effects of the ‘formiguer’ on its soil cover in terms of changes in nutrient availability. We built an experimental 0.5-m3 ‘formiguer’ with 68 kg of plant material with a 12% moisture content and 550 kg of soil with a 16% moisture content. The content of organic carbon and mineral nitrogen decreased in the soil cover as a result of burning. After aerobic incubation all samples had a similar content of mineral nitrogen. Exchangeable potassium and total and labile phosphorus increased after burning as a result of the soil cover mixing with the ashes of the biomass as the ‘formiguer’ collapsed during burning in the first two cases, while mineralization of organic compounds produced the increase in labile phosphorus. This input of nutrients for the agricultural plots occurs at a net loss of 0.4–2.5 Mg organic C ha−1. Very small amounts of charcoal were produced and this may be the reason for their low occurrence in soils today. Burning of ‘formiguers’ required the harvest of vegetation from a considerable forest area (10–25 ha per hectare of agricultural land) and represented a significant disturbance of these systems.

[1]  Marc Badia-Miró,et al.  THE GRAPE PHYLLOXERA PLAGUE AS A NATURAL EXPERIMENT: THE UPKEEP OF VINEYARDS IN CATALONIA (SPAIN), 1858–1935 , 2010 .

[2]  J. Homburg Amazonian dark earths: Origins, properties, management , 2007 .

[3]  J. Lehmann,et al.  Ameliorating physical and chemical properties of highly weathered soils in the tropics with charcoal – a review , 2002, Biology and Fertility of Soils.

[4]  M. Engelhard,et al.  Long-term black carbon dynamics in cultivated soil , 2008 .

[5]  D. Rowell,et al.  The role of gypsum in the reactions of phosphate with soils , 2006 .

[6]  Christian P. Giardina,et al.  The effects of slash burning on ecosystem nutrients during the land preparation phase of shifting cultivation , 2000, Plant and Soil.

[7]  P. Khanna,et al.  Changes in heated and autoclaved forest soils of S.E. Australia. I. Carbon and nitrogen , 1995 .

[8]  P. Abrahams,et al.  An investigation of former land-use activity through the physical and chemical analysis of soils from the Isle of Lewis, Outer Hebrides , 2000 .

[9]  J. R. O. Alberdi,et al.  Efectos de un incendio sobre diversas propiedades físico-químicas del suelo y procesos de erosión hídrica en medio semiárido (La Granja d'Escarp, Lleida) , 2008 .

[10]  D. Badía,et al.  Plant Ash and Heat Intensity Effects on Chemicaland Physical Properties of Two Contrasting Soils , 2003 .

[11]  Enric Tello,et al.  Una interpretación de los cambios de uso del suelo desde el punto de vista del metabolismo social agrario. La comarca catalana del Vallès, 1853-2004 , 2008 .

[12]  F. Niell,et al.  Mobilization of nutrients by fire in a semiarid gorse‐scrubland ecosystem of Southern Spain , 1995 .

[13]  D. Binkley,et al.  Ecology and Management of Forest Soils , 2000 .

[14]  Teresa Gavilà Treball de recerca , 2010 .

[15]  D. Badía,et al.  Effect of Simulated Fire on Organic Matter and Selected Microbiological Properties of Two Contrasting Soils , 2003 .

[16]  E. Tello,et al.  Preserving and destroying soils, transforming landscapes: Soils and land-use changes in the Vallès County (Catalunya, Spain) 1853–2004 , 2008 .

[17]  R. Shiel Debating Shifting Cultivation in the Eastern Himalayas , 2007 .

[18]  M. Benoît,et al.  Influence des anciennes pratiques agricoles sur la végétation et les sols des forêts reboisées dans le massif vosgien , 1999 .

[19]  M. Ogawa,et al.  Effects of the application of charred bark of Acacia mangium on the yield of maize, cowpea and peanut, and soil chemical properties in South Sumatra, Indonesia , 2006 .

[20]  E. H. Tryon,et al.  Effect of Charcoal on Certain Physical, Chemical, and Biological Properties of Forest Soils , 1948 .

[21]  X. Cussó,et al.  Social metabolism in an agrarian region of Catalonia (Spain) in 1860-1870: Flows, energy balance and land use , 2006 .

[22]  John Gaunt,et al.  Bio-char Sequestration in Terrestrial Ecosystems – A Review , 2006 .

[23]  M. D. Molina,et al.  Preindustrial agriculture versus organic agriculture: The land cost of sustainability , 2009 .

[24]  D. Wardle,et al.  Fire-Derived Charcoal Causes Loss of Forest Humus , 2008, Science.

[25]  E. Rotenberg,et al.  Respiration acclimation contributes to high carbon‐use efficiency in a seasonally dry pine forest , 2008 .

[26]  W. Woods Development of Anthrosol Research , 2003 .

[27]  E. Sharma,et al.  Debating Shifting Cultivation in the Eastern Himalayas; Farmers' Innovations as Lessons for Policy , 2006 .

[28]  F. Maris,et al.  The effect of stand age on the accumulation of nutrients in the aboveground components of an Aleppo pine ecosystem , 2001 .

[29]  S. Christiansen Flows of matter in a traditional heathland farm about 1840. An example from northern West Jutland, Denmark , 2001 .

[30]  H. Fritze,et al.  Charcoal as a habitat for microbes and its effect on the microbial community of the underlying humus , 2000 .

[31]  P. Bienkowski,et al.  Some Remarks About the Effect of Smoke from Charcoal Kilns on Soil Degradation , 1999 .

[32]  P. Khanna,et al.  Effects of heating and autoclaving on sorption and desorption of phosphorus in some forest soils , 2008, Biology and Fertility of Soils.

[33]  B. K. Mishra,et al.  Slash and burn agriculture at higher elevations in North-Eastern India. I. Sediment, water and nutrient losses , 1983 .

[34]  C. Giardina,et al.  Changes in Soil Phosphorus and Nitrogen During Slash‐and‐Burn Clearing of a Dry Tropical Forest , 2000 .

[35]  C. Birch,et al.  Fertiliser N and P application on two Vertosols in north-eastern Australia. 3. Grain N uptake and yield by crop/fallow combination, and cumulative grain N removal and fertiliser N recovery in grain , 2010 .

[36]  A. Piccolo,et al.  Effects of coal derived humic substances on water retention and structural stability of Mediterranean soils , 1996 .

[37]  P. Virkajärvi,et al.  Phosphorus fertilization: a meta-analysis of 80 years of research in Finland. , 2009 .

[38]  M. Turner,et al.  Interactions between past land use, life-history traits and understory spatial heterogeneity , 2006, Landscape Ecology.

[39]  B. Emmett,et al.  Response of plant species richness and primary productivity in shrublands along a north–south gradient in Europe to seven years of experimental warming and drought: reductions in primary productivity in the heat and drought year of 2003 , 2007 .

[40]  K. Sahrawat,et al.  Relationships of barley biomass and grain yields to soil properties within a field in the arid region: Use of factor analysis , 2009 .

[41]  B. K. Mishra,et al.  Slash and burn agriculture at higher elevations in north-eastern India. II. Soil fertility changes , 1983 .

[42]  R. J. Raison,et al.  Effects of slash burning on soil phosphorus fractions and sorption and desorption of phosphorus , 1994 .

[43]  James J Stapleton,et al.  Time and Temperature Requirements for Weed Seed Thermal Death , 2007, Weed Science.

[44]  高橋 正通 Ecology and Management of Forest Soils 3rd Edition, R.F.Fisher and D.Binkley 著, ISBN 0-471-19426-3,24×16cm, 489pp., $99.00(本体価格), John Wile &Sons, Inc.(New York), 2000年 , 2001 .

[45]  P. Marschner,et al.  Dynamics of C, N, P and microbial community composition in particulate soil organic matter during residue decomposition , 2008, Plant and Soil.