The project ‘Divergent responses to global warming in the biodiversity of agroecosystems. Search for weed species indicative of climate change’, launched by the National Institute of Agricultural and Food Research and Technology (INIA) consists of assessing the effect of climate change on the diversity of weed species present in cereal agroecosystems in the south-central Iberian Peninsula. The initiative has the support of the Biodiversity Foundation.

In general, biodiversity monitoring is a means of obtaining information about the state of the ecosystem and its dynamics of change in relation to human activities that take place within an area. It is based on the regular observation of potential changes in previously agreed variables in a given time and area, and on their subsequent evaluation. Within this framework of action, the implementation of a monitoring program for weed species in cereal agro-ecosystems, in the area object of this study (south-central area of the peninsula), contributes to the detection of changes. The knowledge generated about the presence of weed species in the different latitudes studied, allows an adequate management of the impact that changes in environmental variables may produce, so that it can be avoided and/or minimized, while ensuring that management measures are effective. The geographical location of weed species, more or less thermophilic, in cereal agro-ecosystems, contributes to the detection of temperature changes that, on a regional or local scale, may occur in these systems. Thus, as general conclusions of this project we highlight:

1. Climate change influences the pressure that weeds exert on agro-ecosystems.

2. The ecosystem services provided by weeds in cereal agro-ecosystems may be compromised by climate change.

3. Weeds can be an indicator tool of a change in environmental conditions.

4. Requirements have been established to consider a weed potentially indicative of a change in climatic conditions.

5. The geographical distribution patterns of temperature-sensitive weeds may facilitate the design of new weed management strategies in future scenarios of global change.