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The National Forest Inventory in the Czech Republic

A primary aim of the National Forest Inventory (NFI) is to provide objective and independent information regarding the state and changes of forests within the Czech Republic. This information is necessary for the sake of the formulation of a viable forestry policy and to enable evidence-based decision-making on forestry-related issues. A survey, based on sound sampling methodology, is a key principle of the Czech NFI. Data is collected through repeated fieldwork on sample plots located throughout the Czech Republic. The ultimate NFI output corresponds to estimates of predefined parameters (attributes of the Czech forests and landscape). These estimates can be produced for the level of the whole Czech Republic or its predefined subregions (e.g. NUTS regions or natural forest regions). Accuracy of NFI results is expressed by means of standard errors and confidence intervals.

The importance of the National Forest Inventory

The role of the NFI consists in the provision of sufficiently updated, objective and precise information regarding the state and changes of forests within the Czech Republic and its smaller territorial units (e.g. NUTS regions and natural forest regions).

Based only on precise enough, objective information, it is possible to develop an appropriate forestry policy and to evaluate its impact on forests and the forestry sector simultaneously. The NFI based on a field assessment, following principles of modern sample surveys, is the most appropriate source of information for this purpose. The information from the NFI enables to coordinate forestry-related political decisions uniquely and to formulate joint forestry strategies at a level transcending national borders. Last but not least NFI results are the most appropriate source of information for the sake of international reporting on the state of forests.

So far, mainly summary data from forest management plans (FMPs) has been used for the above purposes in the Czech Republic. However, the information, obtained through the FMPs regarding Czech forests, differs substantially from the NFI data in many aspects. Differences mainly result from the essence of the FMPs, which primarily serve as a tool of a forest owner or manager to operate within a particular forest enterprise. This is also reflected in the list of attributes included in the FMPs, which is significantly narrower and timber production-oriented as compared to the NFI. Another fact is that the FMPs are processed only for the forest fund, i.e. for land legally devoted to forestry purposes (according to the land registry) whilst the NFI survey covers all forests, following international definitions of land categories. Also, the methodology of forest assessment applied within FMPs elaboration does not guarantee unbiasedness of the information obtained.

Summary of the main NFI principles

In terms of the NFI, the land cover as a whole is analysed first, and only then it is possible to focus the sample survey on the forest land category, the occurrence of which is not pre-specified in any way (e.g. by the land registry or status according to the FMPs). Valuable information for the sector of environment protection and landscape engineering can thus be provided. Quite recently, the many NFIs (particularly in Europe) extended their scope beyond the forest land category in order to address information needs existing at the whole landscape level.

Within the modern NFI, a representative sample of locations (sample plots) is surveyed in a field in order to obtain a wide range of data, which is subsequently evaluated by contemporary methods of survey sampling. Ultimate NFI results correspond to estimates of predefined target parameters (totals, mean values, amounts recalculated per unit area) including sound accuracy measures in the form of confidence intervals or standard errors. The objective way of working with uncertainty of provided information, the continuous and provable process of quality assurance (of collected data and all phases of its processing) and finally the use of internationally harmonised definitions – these are the essential features that distinguish the modern NFI from other sources of information about forests.