Effects of environmentally friendly farming and multi-scale environmental factors on generalist predators in rice paddy ecosystems of Japan

Generalist predators such as spiders and ground beetles provide important ecosystem services by suppressing density of pest insects in agroecosystems, which offers a sustainable solution to trade-off between agricultural production and biodiversity conservation. There is increasing recognition that landscape factors beyond field-plot scale are important determinants for community structure of generalist predator as well as within-farmland practice, because surrounding environments serve as alternative habitats for them during time when arable fields are ill-suited [1]. Additionally, macro-scale factors such as climate and topography are beginning to receive much attention as important drivers for farmland biodiversity at a large spatial-scale [2]. Based on these backgrounds, many studies have been conducted to explore how the multi-scale factors determine abundance and diversity of generalist predators in upland farmlands (e.g. wheat fields and meadows) around European countries, but very few studies have been carried out in rice paddy fields which are among the major types of farmland in Asian countries. Here, I will present some of the results of the research projects which explored how agricultural practice and environmental factors influence generalist predators in rice paddy ecosystems of Japan.