Project
The agroecology of the arable field
In the frame of the multi-country project FRESHH we will study carabid beetles, seed predation, weed communities, surrounding landscape, farmer practices, and surface water in adjacent water courses in 20 wheat fields in Drenthe. We do this to better understand how farmer practices in weed control affect carabid beetles and surface water quality while we also hope to identify the effect of carabid beetles on the weeds.
Project description
Carabid beetles are commonly present in arable crop fields where they contribute to weed seed predation, which benefits farmers by controlling weeds. On the other hand, carabids benefit from presence of weeds as these produce cover and provide food. Farmers control weeds to prevent yield reductions, but this negatively affects carabid beetles and the weed control function that carabids may exert if they are abundant enough. Moreover, herbicides may spill over to nearby water courses where they can affect the water quality. Finally, carabids and weeds in arable crops are affected by the habitats surrounding the field and the width of the buffer strip between the field and the water course. The width of this buffer strip also affects whether herbicide use in the arable field will affect the quality of the adjacent surface water. We will measure carabids by pitfall trapping, weed seed predation by seed cards, weed communities by quadrat counts, landscape by GIS and ground truthing, and water quality by e(nvironmental)DNA sampling. Management of the field will be determined by communicating with the farmers. Within a 5-country project with 20 field sites in each country, we hope to determine how carabids may help farmers to control weeds and thereby reduce the need for herbicide use and the effects of herbicides on surface water quality. We would like to engage 2-4 students in this project who could take on different tasks, such as the trapping and identification of carabid beetles, the measurement of weed seed predation, the description of weed communities, the mapping of landscape surrounding the fields or the collection of water samples for eDNA.
Objectives and methods
The objective is to better understand how carabids may help farmers to control weeds and thereby reduce the need for herbicide use and the effects of herbicides on surface water quality. Students take responsibility for part of the data collection, i.e. trapping and identification of carabid beetles, the measurement of weed seed predation, the description of weed communities, the mapping of landscape surrounding the fields or the collection of water samples for eDNA. They analyse data and write their thesis on the basis of collected data.
Expectations
Clear protocols are available for the different tasks. It is expected that students carry out the measurements according to protocol, but have an open mind on what else may be noted and measured.
Required skills
Students should have an affinity with agroecological field research. Ideally students would have a background in Plant Sciences (agronomy) or Forest and Nature Conservation, with courses in the domain of ecological methods for field research. A drivers licence is useful but not required.
Period
The field work will be conducted in April/May 2024, depending on the weather. The ideas candidate(s) will start well ahead of this period to prepare all materials for the field work and practice the field methods in the field in Wageningen.
Location
Veenkoloniën Drenthe
