Abstract:
In order to assess the dynamics of arthropod biodiversity and community structure in a typical winter paddy field, investigations were carried out in 5 typical cropping systems, including early-rice-late-rice-winter-potato (RRP), rice-rice-winter-vegetable (RRV), rice-rice-winter-fallow (WF), field-ridge rice-rice-winter-fallow (FR) and rice-rice-winter-turnover-plow (PF) during the winter of 2005~2007 in 12 townships of Enping City, South China. Results for the winter of 2005~2006 show that spider is the dominant arthropod species in the 5 plots, while lepidoptera dominates in RRV treatment. Biodiversity index is significantly different (
P<0.05) among the 5 treatments. The indexes of richness eveness (
DG) and density (
J) in RRV and RRP treatments are higher than the other three. Shannon-Wiener diversity indexes (
H) in FR and RRV treatments are 1.865 9±0.103 7 and 1.590 9±0.093 8 respectively, which are higher than the other treatments. The highest densitygroup index (
DG) is 7.595 0±0.047 6, existing in RRV treatment. Results for 2006~2007 are similar to those for 2005~2006. RRV and FR treatments have higher
H 1.782 5±0.145 4 and 1.137 9±0.101 5,than the others. The highest diversitygroup index (
DG) is 11.210 3±0.351 2 in RRV treatment. Sorenson similarity index (S
1) is highest between WF and RRP treatments, while PF and FR treatments have low S
1. Whittaker similarity index S
2 between FR and RRP treatments is the highest, while RRV and RRP treatments have the lowest. In conclusion therefore, biodiversity of winter-turnover-plow (PF) is significantly different from the other cropping systems, and ricericewintervegetable (RRV) system has a significant effect on biodiversity enhancement in paddy fields.