Monitoring phytosanitaire des essences ligneuses des berges de cours d’eau

Context

In February 2001, the CRA-W and FUSAGx started a joint study of Phytophthora alder disease (Phytophthora alni) in the Walloon region. Over three years, this study quantified the extent and evolution of the disease along watercourses. This resulted in significant advances in understanding the infection mechanism of the disease. Recommendations for river bank management were prepared. During this phase, a large amount of characterisation data were collected during the monitoring of a network of sample plots throughout the Walloon region. Entry of this information into a database together with a large plant pathology laboratory research study and follow-up tests in the field all assisted in studying alder and riparian vegetation disease in Wallonia. The wealth of information opened up new avenues of applied research within the scope of watercourse bank management : expansion of the phytosanitary study to other river bank species, continuation of the Phytophthora alder disease study, development of a multi-objective inventory method. Other phytosanitary problems could affect woody species of river banks, representing a threat to the riparian environment. The development of a complete monitoring tool for this watercourse vegetation is therefore essential. This study will allow Wallonia to achieve certain objectives set by the European Community in the Framework Directive on water and in the Natura 2000 project.

Objectives

- Finalisation of the Phytophthora alder disease study: plant pathology aspects (laboratory analysis and monitoring of the health status of riparian corridors) and management aspects (follow-up of forestry trials). Details of this first objective are not included here since there is a CRA-W scientific project data sheet devoted entirely to it. - The extension of the study and Phytophthora alder disease monitoring to other phytosanitary problems affecting both alders and other woody species of watercourses: development of an inventory method and identification of potential phytosanitary problems affecting these species. - The extension of the inventory method to a multi-objective approach, for use in scientific studies, phytosanitary monitoring of watercourses and the general evaluation of river system management.

Description of tasks

Phytosanitary monitoring of the woody species of river banks involves listing the diseases and insect pests present in 22 woody species of riparian corridors along Walloon watercourses. From the data collected from an existing network of sample plots (plots selected in 2002 for monitoring Phytophthora alder disease in Wallonia), a network of about hundred sample plots throughout the Walloon region was chosen. Four information and sample collection campaigns have been scheduled for spring and summer 2004 and 2005. The data collected will be entered into a database to provide the best characterisation of the phytosanitary status of woody species of Walloon watercourses. In the laboratory, identifications will be based on cultures of pathogenic fungi and the rearing of insect pests. Information concerning any phytosanitary problems could also be collected in collaboration with Walloon watercourse managers.

Expected results

Phytosanitary monitoring of river bank woody species is intended to provide information on the diseases and insect pests present along Walloon rivers and to detect any new “threats” to the woody vegetation of river banks. It will also serve to implement European legislation relating to watercourses and their direct environment (Framework Directive on water, Natura 2000 network). Finally, management and consultation services will be set up to assist managers.

Contribution

- Preparation of a phytosanitary listing protocol applied to the Walloon river system. - Setting up of a database to process the information obtained from this list. - Design of information sheets for managers, explaining the main phytosanitary problems encountered. - Setting up of a consultation service specific to the riparian environment.

Partners

This project is being conducted by two institutions : - The Walloon Agricultural Research Centre for all phytosanitary aspects ;

- Gembloux Agricultural University (Forestry Resources and Natural Environments Management Unit) which is developing a multi-objective inventory method to ensure global monitoring of the riparian environment in the Walloon region or within the scope of a river sub-basin.