A clear definition, discerning as main components of agrobiodiversity (1) the genetic variety of domesticated plants and animals, (2) life suppport systems and (3) all wild flora and fauna on farmland is very useful. Such components of biodiversity should not be identified as items without relationship to each other: "domestic", "small" and "wild" agrobiodiversity are presently placed in separate categories by modern scientist and policy makers, not by farmers or nature itself.
Agricultural biodiversity has been described as including: a) harvested crop varieties, livestock breeds, fish species and non-domesticated ('wild') resources within field, forest, rangeland and aquatic ecosystems; b) non-harvested species within production ecosystems that support food provision, including soil micro-organisms, pollinators, green manures, biocontrol organisms and so forth; and c) non-harvested species in the wider environment that support food production ecosystems, (agricultural, pastoral, forest and aquatic) including landraces, 'wild' relatives of crops and livestock, environmental plants such as windbreaks for soil erosion control, etc.
Agrobiodiversity will have to address all biodiversity in agricultural areas. It should not only focus on biodiversity relevant to food and agriculture. Like the programmes on coastal and marine biodiversity addressing all biodiversity and not just fish, and the programmes on forest biodiversity paying attention to all biodiversity in forests, not just on trees. This is logical because of the strong interrelationship of all biodiversity within these systems, but also because of the ambition of the CBD to cover all biodiversity on earth through the set of thematic work programmes.
The European Parties to the CBD expressed the need for a clearly defined, broad scope at the SBSTTA-5 meeting in February 2000. Part of this is reflected in the recommendation to COP-5: "Agricultural biodiversity is a broad term that includes all components of biological diversity of relevance to food and agriculture, and all components of biological diversity that constitute the agro-ecosystem: the variety and variability of animals, plants and micro-organisms, at the genetic, species and ecosystem levels, which are necessary to sustain key functions of the agro-ecosystem, its structure and processes, in accordance with annex I of decision III/11."< The international technical workshop on "Sustaining Agricultural Biodiversity and Agro-Ecosystem Function", jointly organised by FAO and the Secretariat of the CBD, with the support of the Government of the Netherlands (Rome, 1998) defined agrobiodiversity thus: "Agricultural biodiversity refers to the variety and variability of animals, plants, and micro-organisms on earth that are important to food and agriculture which result from the interaction between the environment, genetic resources and the management systems and practices used by people. It takes into account not only genetic, species and agro-ecosystem diversity and the different ways land and water resources are used for production, but also cultural diversity, which influences human interactions at all levels. It has spatial, temporal and scale dimensions. It comprises the diversity of genetic resources (varieties, breeds, etc.) and species used directly or indirectly for food and agriculture (including, in the FAO definition, crops, livestock, forestry and fisheries) for the production of food, fodder, fibre, fuel and pharmaceuticals, the diversity of species that support production (soil biota, pollinators, predators, etc.) and those in the wider environment that support agro-ecosystems (agricultural, pastoral, forest and aquatic), as well as the diversity of the agro-ecosystems themselves".
Other definitions shift attention from its components to the relationships between these and between the wider biodiversity, such as the definition proposed by IUCN in a Background study for the development of an IUCN Policy on Agriculture and Biodiversity (1999). While this definition overcomes some of the difficulties with the ones cited above, notably the problematic distinction between domestic and wild biodiversity, it could be seen as an "ecologists" definition in that it has lost a clear socio-economic and cultural element as well as the relationship of biodiversity to the production function of agriculture: "The agrobiodiversity of a place or region is largely analogous to its biological diversity: it describes the range and variety of biological diversity within the farmed landscape. As farming has altered, and come to replace, the previous pattern of habitats and communities, agrobiodiversity also describes the range of different structures in the landscape, such as hedges and trees. For example, the agrobiodiversity of an up-land farm will summarise the obvious range of biological diversity and the variety of landscape features from the meadows, the walled and hedged fields through to marshland and small wooded areas."< OECD work on environmental indicators for agriculture including those for agrobiodiversity refers to the three different levels of Biodiversity (Genetic, Species and Ecosystem) and thirteen areas which range from wildlife habitat and biodiversity to farm financial resources and farm management, from nutrient use and soil quality to landscape and socio-cultural issues.