Integrated Rice-Duck Farming Decreases Soil Seed Bank and Weed Density in a Paddy Field

Hui Wei,Huimin Xiang,Guoming Quan,Jiaen Zhang,Wenjuan Bai,Rui Chen

doi:10.3390/agronomy9050259

Abstract

Coupled cropping-breeding modes have been highly recommended due to their ecological and sustainable nature. Integrated rice-duck farming is a typical ecological planting system in rice paddy fields and has been widely popularized in Asia where a considerable area of cropland has been planting rice. In this study, two experimental treatments of turbid water or rice-duck treatment were established to compare with the control and a conventional treatment in absence of ducks. The turbid water treatment imitated the muddying effect by duck activities with the trampling and foraging effects excluded, while the rice-duck treatment included all of the mentioned effects by raising ducks in rice paddy field. Results showed that the rice-duck treatment significantly reduced soil seed bank density by more than 40% and the figures under the turbid water treatment were 18.2% and 30.5%, accordingly, in the early and late rice growing seasons. Moreover, the rice-duck treatment significantly altered the vertical distribution of soil seed bank by substantially declining the seed density in the topsoil (0–5 cm). Changes in soil seed bank density considerably contributed to the declines in above-ground weed density because a significant correlation was detected between the soil seed bank density in the early season and the weed density in the late season. Our results of declined soil seed bank and weed density in integrated rice-duck farming imply that this system is highly efficient as a biological pathway for controlling weeds.

Highlights

Rapid growing yield of crops by industrial agriculture associated with intensive application of agrochemicals has succeeded to feed the increasing population worldwide [1]
At the end of the late season, in total, nine species in six families were detected in soil seed bank, with the number of species being nine in the control, conventional planting, and turbid water treatment plots, and eight in the rice-duck farming plots (Table 2)
The changes in the light environment could contribute to weed control, because reduced light intensity and altered light composition could probably lower germination of several seeds in the soil [27,36], and the lower weed abundance resulted in the reduction of soil seed bank density

Summary

Introduction

Rapid growing yield of crops by industrial agriculture associated with intensive application of agrochemicals has succeeded to feed the increasing population worldwide [1]. Integrated rice-duck farming is a popular plant-raising system due to its economic, environmental, and ecological benefits reported previously [7]. By contrast, integrated rice-duck farming may enable reduced use of agrochemicals to improve environment of croplands and quality of crops [8,10,13]. Rice-duck farming may be able to mitigate global warming potential by remarkably reducing soil CH4 emission [14,15,16]. This reduction could be associated with the combination of reductions in soil

Results

Discussion

Conclusion