Meta-analysis
Meta-analysis
Forests provide us with a large number of ecosystem services. Therefore, in the case of a forest fire, these services are lost or decreased, and hence the need to account for this type of loss. It is important to keep in mind that part of these ecosystem services does not have an associated market value or price, this does not mean that they do not imply an economic loss. Hence the need to economically value all goods and services that we obtain from natural resources.
In general, there is a shortage of studies that address all of the economic damage caused by forest fires. In this regard, it is worth noting the study carried out by Barrio, Loureiro and Chas (2007) in which the forest fires caused in Galicia in 2006 are valued and which includes both the damages caused by the loss of wood, as CO2 storage, or damage to biodiversity, in addition to pure environmental damage (or passive use values). Given the scarce literature available regarding the valuation of the total economic loss caused by a forest fire, a benefit transfer analysis can be performed. To do this, first, it is necessary to perform a meta-analysis
A meta-analysis is a tool that allows us, through the collection of data obtained in a large number of studies, to draw general conclusions about them (Glass et al. 1981), that is, to transfer the benefits. This analysis consists of several steps; The first step is to be clear about the hypothesis of interest or aspect that you want to analyze. Subsequently it is necessary to make a bibliographic review about it identifying the original studies that are going to be studied. The third step consists in coding the data or the economic valuation measures of interest. In the fourth step, the general conclusions on the topic of study of interest are obtained through the estimation of statistical models. Finally, in a fifth step would be the transfer of benefits, in which the economic values for the selected services can be predicted.
Assessment of ecosystem services in Alto-Minho
‣ Step 1: Objective
The objective of this meta-analysis is to be able to know the economic value per hectare of ecosystem services.
‣ Step 2: Bibliographic search
Build a database by collecting the information provided by the valuation studies that have been carried out on the issue of interest. Final database of 31 studies.
To include them, it was evaluated that:
they made an evaluation per hectare of ecosystem services or that it could be calculated,
they treated the ecosystem services of the forests,
they used economic techniques for the evaluation of the ecosystem services,
that they were not excessively old (since the 1990s)
that their location was as close as possible to Portugal or were similar types of forest to theirs.
We reviewed articles about economic valuation of ecosystem services published in:
WOS;
journals Nature and Science;
American Economic Review;
London School Of Economics;
Academic google;
other databases used for projects similar to this one by the same research group
bibliography of Quintas-Soriano et al. (2016)
These works contain assessments of ecosystem services in different parts of the world:
‣ Step 3: Data Encoding
Classification of ecosystem services
According to the CICES classification, the main categories of ecosystem services are:
Provision: this is a section that contains products from living systems (nutritional, non-nutritional, material and energy).
Regulation and maintenance: this section deals with "all the ways in which living organisms can mediate or moderate the environmental environment that affects human health, safety or comfort along with the abiotic equivalents."
Cultural: the section contains "all non-material products, and usually non-rival and non-consumptive ecosystems (biotic and abiotic) that affect the physical and mental states of people." They represent environmental environments, places, locations that influence the mental states of individuals.
Haynes-Young and Potschin (2018) explain in the last guide on the application of CICES that the conceptual framework of classification can specify in a cascade model (table below). The objective is to classify ecosystem services, this means carrying out a classification of the contributions that ecosystems provide to our well-being. It is also specified that these services are the results provided for ecosystems, therefore, they are final services.
2. Classification of the rest of the variables
The dependent variable, that is, the variable to be explained is the value of the ecosystem services (lnvalor).
The independent variables that explain this assessment represent the characteristics of the study, socio-economic characteristics of the place where the assessment was carried out and finally, the services identified. You can see the different variables and their characteristics in the table on the right:
‣ Step 4: Estimation of statistical models
Taking into account that, in this database, several observations come from the same study, an Ordinary Minimum Squares (OLS) model is estimated with a cluster that identifies that the same study provides different observations and a Random Effects (EA) model, specifying a panel data structure.