Knowledge gaps with respect to the effects of genetically modified crops on the functioning of soil ecosystems
This report presents the results of an inventory of needs and knowledge gaps with respect to the effects of genetically modified (GM) plants on soil ecosystems, with the goal of defining areas in need of future research attention. This inventory consisted of a questionnaire and related interviews that were presented to a variety of interested parties, including growers, horticultural companies and scientists. Results of this questionnaire were compiled together with knowledge gained through a number of workshops and scientific meetings and past research efforts dedicated to this topic. Given the huge impact that plants have on soil systems, and the importance of these systems for sustainable agricultural practices, the question of whether GM crops have harmful effects on soil systems has received increased attention in recent years. In the agro-ecosystem context covered in this report, this refers to effects within the scope of standard agricultural practices in the Netherlands, wherein a healthy soil is defined as one that supports sustained crop yield over a range of environmental stresses, without requiring escalating levels of input or affecting surrounding habitats. Within this framework, the most important general functions of agricultural soil systems were determined to be 1.) cycling of nutrients and organic matter, 2.) buffering against biotic and abiotic stresses, and 3.) maintaining proper soil structure. Soil biota are for the most part responsible for these functions, and risk assessment efforts seek to determine if unintended perturbation of soil-borne communities via GM crop cultivation might disturb the procurement of these key soil functions.