The standard System of National Accounts (SNA) does not estimate the margins of the products without market prices consumed because it assumes that the cost prices of the final products consumed correspond to the consumer marginal willingness to pay (MWTP). Valuations of products consumed without market prices at their cost prices may not coincide with their simulated exchange values (SEV) that would be paid by consumers. This inconsistent SNA valuation can be avoided by simulating stated or revealed market prices based on consumers’ demands. Our Agroforestry Accounting System (AAS) methodology estimates the margins of the individual products without market prices based on the consumer MWTP. The SEV of private owners and public consumers MWTP for these non-market products are estimated in this study by applying stated and revealed preference valuation methods. The objectives of this study are to compare the environmental incomes, ecosystem services and profitability rates obtained by applying the AAS and the refined SNA (rSNA) methodologies to the case-study oak woodland dehesa and conifer forest farms in Andalusia, Spain. The 41 farms comprise 26 large oak woodland dehesa farms in which trees of the Quercus genus predominate, and 15 conifer forest farms where Pinus species predominate. In the studied farms, 20 individual activities have been identified which 19 are common to both the AAS and rSNA approaches, along with the additional activity of carbon which is registered in the AAS. Ownership rights of 13 private activities correspond to the farmer and 7 public activities to the government. In 2010, the case-study results show that livestock and game species consume grazed fodder which represents 50% and 95%, respectively, of their total forage units consumed in the period 2010. Livestock farming accounts for 31% of the labour compensation in the private oak woodland dehesa farms and 1% in the public conifer forest farms for the farm activities as a whole. The ecosystem services measured by the AAS in the privately-owned oak woodland dehesa and publicly-owned conifer forest farms are 2.7 and 4.6 times greater, respectively, than those estimated by the rSNA. The environmental incomes measured by the AAS for the privately-owned oak woodland dehesa and publicly-owned conifer forest farms account for 61% and 53%, respectively, of their total incomes.
Twenty‐five years of tree demography in a frequently burned oak woodland: implications for savanna restoration
