Crop Growth Characteristics and Waterlogging Risk Analysis of Huaibei Plain in Anhui Province, China

摘要

Within the context of global warming, climate extremes, including heavy rainfall events, have become one of the most significant and attractive themes around the world. The target region of this study is confined to Huaibei Plain, an important agricultural production base in China, where the wet climate extremes can cause considerable damages to the economy, particularly to agriculture. In this study, lysimeter measurements at the Wudaogou Hydrological Experiment Station in Huaibei Plain region were used for analyzing the effects of the water table on crop growth and production. The crops studied included summer maize, winter wheat, and summer soybean. From the interannual and intraseasonal scale, temporal and spatial distributions of heavy rainfall events for 49 stations in Huaibei Plain over the period 1951-2012 were examined rigorously by means of the Fortran language. The results demonstrate that an optimum groundwater depth range in which crop yields were highest was observed for all three crop species analyzed (0.8-2.5 m for maize, 0.8-1.5 m for wheat, and 0.8-1.2 m for soybean). As groundwater levels become shallower than these depth bands, crop yields declined sharply, suggesting negative effects of waterlogging and root anoxia. Groundwater levels greater than these depth bands were associated with gradually declining yields because deeper ground-water could not compensate (through phreatic evaporation) for rainless periods of moisture stress during the growing season. Heavy rainfall events have shown an increased and spreading trend since 1950s, especially in the 1990s. The frequency, duration, and precipitation of heavy rains in Huaibei Plain show a tendency of spreading from some areas to the whole region during the 1950s-2000s, and the number of heavy rains entered into a period of increase during the 1990s-2000s. The waterlog disaster is still one main factor that strains local agricultural production due to the incomplete drainage system in Huaibei Plain.