Determining environmental minimum requirements for functions provided by agro-ecosystemsOlaf Bastiana, Claudia Cortib and Marco Lebboronib
a Saxon Academy of Sciences and Humanities, Working Group on Natural Balance and Regional Characteristics, Neustädter Markt 19 (Blockhaus), 01097 Dresden, Germany
b Dipartimento di Biologia Animale e Genetica, Università di Firenze, Via Romana, 17, 50125 Firenze, Italia
(Accepted 8 June 2007; published online 18 December 2007)
Abstract - The definition of meaningful and realistic targets is the key element in the development of agri-environmental measures to improve the present situation of agricultural landscapes both from ecological and socio-economic points of view. Such targets should be based on a system of reference values that consider ecological thresholds and the carrying capacity of ecosystems and landscapes as well as the demands and necessities of human society in a specific area. In this way, so-called Environmental Minimum Requirements (EMR) can be prescribed for each indicator selected. With the help of EMR it is possible to envisage the minimum values to be matched by the state indicators, below which the particular environmental function becomes jeopardised at the level of the area under consideration. Thus, the definition of EMR is the crucial step to bridge scientific analyses of the ecological state with socio-economic and political evaluations. In examples of the EU-project AEMBAC, various approaches of determining EMR for indicators in the field of biodiversity, soil, water and `landscape' are described. EMR can be classified according to their sources, spatial differentiation, scale and temporal validity. EMR values can vary between countries and local levels. Admittedly, the definition of EMR should take account of value-free scientific facts but an evaluation step is needed as well as the orientation towards human targets to avoid naturalistic fallacy.
Key words: targets / thresholds / evaluation / carrying capacity / agricultural landscapes / indicators / soils / water / bird / reptile
Corresponding author: Olaf.Bastian@mailbox.tu-dresden.de
© INRA, EDP Sciences 2007