Do Hydrologic Regimes Used in Rice Fields Compromise the Viability of Resting Stages of Aquatic Invertebrates?

作者：Stenert Cristina; Bacca Roberta C; Avila Arthur C; Maltchik Leonardo^*; Rocha Odete

来源：Wetlands, 2010, 30(5): 989-996.

DOI：10.1007/s13157-010-0083-1

• Egg banks
• Fallow phase
• Herbicide
• Hydroperiod
• Microcrustaceans
• Wetland restoration

Irrigated rice fields in southern Brazil remain without surface water for 2 years during the fallow phase. The present study tested the hypothesis that the hydrologic regime adopted in rice fields of southern Brazil does not compromise the viability of resting stages of aquatic invertebrates. Dry sediment samples were collected from 9 rice fields with different durations of the fallow phase: 20 days, 1 year, and 2 years after the harvesting period. A total of 2,853 invertebrates distributed across 40 taxa emerged after rewetting dry sediments over the experiment duration (58 days). The dominant invertebrates were microcrustaceans represented by 1,041 individuals and 17 species. Invertebrate richness and density on rice fields fallowed (i.e., dried) for 1 year were greater than that for rice fields drained 20 days and 2 years. Aquatic invertebrate composition varied between rice fields fallowed for 20 days compared to those that remained dry for 1 or 2 years. The existence of viable resting stages in dry rice sediments over all stages of the fallow phase should help guide wetland restoration initiatives in southern Brazil.

• 出版日期2010-10