The rapid expansion of industrial and "green revolution" agriculture over the last 100 years has resulted in the loss of more than 90 per cent of crop varieties from farmers' fields, and more than half of the breeds of domestic farm animals.
Locally diverse food production systems—the basis of agricultural biodiversity—are under threat globally and, with them, the accompanying local knowledge, culture and skills of the food producers. With this decline, agricultural biodiversity, including harvested and unharvested species, is disappearing.
Globalisation of the food system and intensive international marketing have led to the widespread cultivation and rearing of fewer varieties and breeds for a more uniform, less diverse, competitive global market.
Agricultural biodiversity is defined as the variety and variability of animals, plants and micro-organisms used directly or indirectly for food and agriculture (including, in the FAO definition, crops, livestock, forestry and fisheries). It comprises the diversity of genetic resources (varieties, breeds, etc.) and species used for food, fodder, fibre, fuel and pharmaceuticals. It also includes the diversity of non-harvested species that support production (e.g. soil micro-organisms) 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.
The reduced integration of livestock in arable production, whether as stock or work animals, has resulted in the serious decline of many animal species. The development of mono-crop aquatic production systems in replacement of mixed and natural pond systems has resulted in a breakdown of the fish production environment and the supporting ecosystem.
In the past, wildlife had been able to adjust and exploit the agricultural situations because modifications to the environment had been gradual. However, in the last century and particularly in recent decades, this has changed. Modern machinery and agro-chemicals allow rapid changes to the farmed environment over huge areas, to impose a high-input, standard, factory landscape over the previous characteristic regional features. Other areas have been abandoned.
The rapid modernisation of northwest European agriculture has resulted in intensification, marginalisation, concentration and specialisation of farming. This modernisation continues today in southern Europe—and has begun, and is certain to increase, in central and eastern Europe. It has resulted in a fundamental imbalance between farming and the environment.
The biodiversity and landscape values in much of Europe have suffered a dramatic decline over the last 50 or more years. Semi-natural habitats have become very rare in the Northwest European lowlands and many of the formerly collectively farmed regions in Central and Eastern Europe. However, important strongholds still exist in less intensively farmed regions, like uplands, mountains and certain river valleys. Important Bird Areas are still numerous in Europe but in many cases the quality has declined, especially for breeding birds. Regions rich in landscape features have equally suffered great losses, although important concentrations do still exist, in the Atlantic region. Most of the losses were caused by intensification of agriculture but land abandonment is becoming more and more important as a threat as well. At this moment this is already visible especially in Central and Eastern Europe.
Across much of Europe farming practice can be characterised by increasing specialisation and intensive production. Where production has been the main objective, the result has been a decline in biological and landscape diversity. The picture varies however, as a result of differences in specific agriculture policies employed—for example the levels of funding associated with these policies and the response of farmers. In countries in transition, there have been drastic reductions in agricultural inputs since 1989, which has led to a relatively favourable environmental situation from the viewpoint of nutrients and pesticides. Although this large-scale extensification may have been accompanied by some recovery in the biological diversity in agro-ecosystems, it is likely that the bulk of biodiversity is still concentrated in those areas where it already was before 1989, seeing the long time required for he development of many of these ecosystems. Against the background of recent land redistribution, the collapse of livestock farming in many areas, leading to outright abandonment, and uncertainties about future developments in agriculture as well in policies, the status of these biodiversity rich areas is still highly uncertain.