The influence of landscape simplification on weed traits in Mediterranean cereal boundaries

Abstract

Crop boundaries are important areas supporting weed diversity in agro-ecosystems, although the progressive landscape simplification during the last century has eroded weed richness of these habitats. The ecological processes involved in the diversity loss in response to landscape simplification may be clarified focusing on response traits. The aim of this work was to assess the influence of landscape simplification on weed traits in Mediterranean (Andalusia and Catalonia regions) winter cereal field boundaries. Weed species were recorded in 101 boundaries of conventional cereal fields along a landscape complexity gradient. Weed species were characterized by five traits: life form, growth form, seed mass, seed dispersal type and pollen vector. The relationship between species traits and landscape complexity wes assessed by RLQ analysis. The firls RLQ axis showed a significant association between plant traits and landscape complexity. The different plant traits explored, with the only exception of growth form, explained 62% of the variation found. Traits associated to simple landscape were annual, non-zoochorus, anemogamous and light seeded species. The functional approach of this study can help understand general patterns of response of weed diversity to landscape simplification and to develop agri-environmental policy for weed diversity conservation in Mediterranean areas.