When is a forest a forest? Forest concepts and definitions in the era of forest and landscape restoration

We present a historical overview of forest concepts and definitions, linking these changes with distinct perspectives and management objectives. Policies dealing with a broad range of forest issues are often based on definitions created for the purpose of assessing global forest stocks, which do not distinguish between natural and planted forests or reforests, and which have not proved useful in assessing national and global rates of forest regrowth and restoration. Implementing and monitoring forest and landscape restoration requires additional approaches to defining and assessing forests that reveal the qualities and trajectories of forest patches in a spatially and temporally dynamic landscape matrix. New technologies and participatory assessment of forest states and trajectories offer the potential to operationalize such definitions. Purpose-built and contextualized definitions are needed to support policies that successfully protect, sustain, and regrow forests at national and global scales. We provide a framework to illustrate how different management objectives drive the relative importance of different aspects of forest state, dynamics, and landscape context. Electronic supplementary material The online version of this article (doi:10.1007/s13280-016-0772-y) contains supplementary material, which is available to authorized users.

Von Carlowitz not only elaborated a framework for a modern forestry and wood processing sector. He created the term Nachhaltigkeit by referring to the concept of nachhaltige Nutzung ("sustainable utilization") of the forest. He provided a definition for what became in the following decades the basic understanding of forest management (translation by the author). This term has been used for describing the fundamental goals and achievements in managing forest resources. Forest Lands bearing vegetative associations dominated by trees of any size, capable of producing timber or other forest products or of exerting an influence on the climate or on the water regime. Also, lands from which forests have been recently clear cut or burned, but which will be reforested in the near future. The 1947 inventory had demonstrated clearly that the distinction drawn therein between productive and unproductive forests was an arbitrary one. In the 1958 inventory forests is defined with somewhat more precision than hitherto. Thus, bamboo lands and wattle (Acacia spp.) plantations are specifically included, while savanna types with an average density of tree cover below 0.05 are excluded, as are non-forest crop lands such as rubber and cinchona. This inventory defines accessibility in purely physical terms: "areas within reach of exploitation by existing transportation systems". Forest area alone, however, can convey a very misleading impression of the potential of the forest resource. There is obviously need for some indication, however approximate, of the quality of the forest.
The revised definition of forests in the 1958 inventory, already mentioned, to some extent sharpens the picture the inventory gives us of the forested area, by specifically excluding land with very low timber cover. In addition, a tree cover section asks countries to report the proportions of the exploited forest area in density classes. An important new question asked in the 1963 enquiry was the a ea of "unsto ked fo est land" defined as "lands f om which forests have been clear-cut or burned, but which will be reforested in the fo eseeable futu e" and "lands not suitable for bearing tree cover by their nature, e.g. forest oads small ive s and small wate a eas". It was considered desirable to know how large these areas were and to subtract them from the area to be reported on in the enquiry into density, composition and growing stock. The group considers the FAO definition of a forest as the basic one (FAO, 1998;FRA 2000), but acknowledge that many other useful definitions of "forest" exist in published form. The fact that "forest" has been defined in many ways is a reflection of the diversity of forests and forest ecosystems in the world and of the diversity of human approaches to forests. In this document, a forest is a land area of more than 0.5 ha, with a tree canopy cover of more than 10%, which is not primarily under agricultural or other specific non-forest land use.In the case of young forests or regions where tree growth is climatically suppressed, the trees should be capable of reaching a height of 5 m in situ, and of meeting the canopy cover requirement.
For the definition of forest, FAO adopted the threshold of 10 percent crown cover. Recommended in the landmark study on worldwide vegetation classifications carried out by the United Nations Educational, Scientific and Cultural Organization (UNESCO, 1973), this threshold was used for developing countries in the Forest Resources Assessments of 1980 and 1990, but FRA 2000 was the first assessment to use it as the minimum canopy cover to describe forests in industrialized countries as well.
To make the comparison between forest area in 1990 and 2000 possible, the 1990 national forest area figures derived by the interim 1995 assessment were revised, using the same definitions, methodologies and new inventory data used for calculating the 2000 figures. This established a new baseline for forest cover in 1990. It should be noted that updating national forest area figures from a previous forest resources assessment by incorporating new data is a standard feature of all FAO forest assessments.
"Forest includes natural forests and forest plantations. It is used to refer to land with a tree canopy cover of more than 10 percent and area of more than 0.5 ha. Forests are determined both by the presence of trees and the absence of other predominant land uses. The trees should be able to reach a minimum height of 5 m. Young stands that have not yet but are expected to reach a crown density of 10 percent and tree height of 5 m are included under forest, as are temporarily unstocked areas. The term includes forests used for purposes of production, protection, multiple-use or conservation (i.e. forest in national parks, nature reserves and other protected areas), as well as forest stands on agricultural lands (e.g. windbreaks and shelterbelts of trees with a width of more than 20 m), and rubberwood plantations and cork oak stands. The term specifically excludes stands of trees established primarily for agricultural production, for example fruit tree plantations. It also excludes trees planted in agroforestry systems. b) states that for land use, land-use change and forestry activities under Articles 3.3 and 3.4 of the Kyoto Protocol, the following definition of forest shall apply: " o est' is a minimum a ea of land of 0.05-1.0 hectares with tree crown cover (or equivalent stocking level) of more than 10-30 per cent with trees with the potential to reach a minimum height of 2-5 m at maturity in situ. A forest may consist either of closed forest formations where trees of various storeys and undergrowth cover a high proportion of the ground or open forest. Young natural stands and all plantations which have yet to reach a crown density of 10-30 per cent or tree height of 2-5 m are included under forest, as are areas normally forming part of the forest area which are temporarily unstocked as a result of human intervention such as harvesting or natural causes but which are expected to revert to forest. http://unfccc.int/methods/lulucf/items/3063.php

The Global Partnership on Forest Landscape
Restoration was formed to bring about compromises by restoring a range of forest functions at the landscape level.
The concept of forest landscape restoration (FLR) emerged as is defined as "a planned p o ess to egain e ologi al integrity and enhance human well-being in deforested or degraded landscapes." http://en.wikipedia.org/wiki/Forest_landscape_restora tion -cite_note-1 FLR comprises tools and procedures to integrate site-level forest restoration actions with desirable landscape-level objectives, which are decided upon via various participatory mechanisms among stakeholders. FLR is increasingly being considered in international and national strategies to address some of the major challenges of our time: food and energy security, climate change, poverty alleviation, combating desertification, biodiversity conservation and environmental conservation. FOREST -Land spanning more than 0.5 hectares with Trees higher than 5 meters and a canopy cover of more than 10 percent, or trees able to reach these thresholds in situ.. It does not include land that is predominantly under agricultural or urban land use. http://www.fao.org/docrep/017/ap862e/ap862e00.pdf