Land-use change and agricultural intensification are global phenomena that also affect small-scale and subsistence farming. In rural South India (Kerala: Wayanad district) paddy cultivation has a long tradition, but farming practices changed during the last decades. Paddy cultivation has become more intensified with the introduction of agrochemicals and high yielding varieties. Furthermore, paddy area is transformed for cash crop cultivation which is increasingly popular because of higher

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... ability compared to paddy. Nevertheless, many farmers still continue paddy cultivation. Therefore, this study aims at a better understanding of the impacts of landscape-wide land-use change and intensified cultivation practices on weeds, pests and predators in paddy cultivation, which are little studied so far. In 2011 and 2012 plants, planthoppers and spiders were collected in 18 paddy fields, cultivated by local farmers, applying either high-intensity or low-intensity management. Fields adjacent to homegarden polycultures and banana monocultures were selected to account for the current land-use change. Samples were taken in transects at the edge, the centre and the bund of the fields to consider possible edge effects. The results showed that adjacent banana monocultures enhanced the weed and planthopper population. Furthermore, the abundance of planthoppers was positively related to the density of weedy grasses but negatively affected by weed diversity (dominated by dicots). Spiders in contrast, benefited from weed diversity. However, their population was mainly driven by prey availability. Fertiliser application had an indirect positive effect on spiders through increased insect abundance and weed richness. Furthermore, spider abundance and richness decreased with increasing distance from the field edge, indicating influences of adjacent habitat on paddy field colonisation. The findings of this study suggest that paddy cultivation in Wayanad should consider the identity of adjacent habitat and weeds but also the amount of fertilisers applied to maintain a balanced agroecosystem.