关键词: 原生动物, 原生动物, 环境监测, 污水净化, 土壤污染评价, 环境毒理学

Abstract: A 2-year field experiment was conducted to investigate the effect of substituting basal chemical fertilizers with biofertilizers (NPK BF) on rice yield and its components, SPAD value, N uptake and soil properties relative to chemical fertilizer application (NPK) under equivalent nutrient rates in soils developed from quaternary red clay in a double rice cropping system. Results showed that compared with NPK, NPK BF tended to reduce the early rice yield, but did not significantly affect the late rice yield. NPK BF tended to reduce the number of panicles and increase the percentage of filled grains in both the early and late rice. NPK BF reduced the SPAD value at the mid-tillering stage and the total N accumulation at maturity in both years, particularly for the early rice in 2014. NPK BF significantly reduced the N recovery efficiency except the late rice in 2013. NPK BF did not significantly affect the soil pH and the concentration of soil total N, while tending to increase the concentration of soil organic carbon and available nitrogen and significantly enhancing the concentration of the available phosphorous after the 2-year experiment. The present results indicated that partial substitution of chemical fertilizers with biofertilizers had no significant effects on rice yield and soil properties in the short term in the double rice cropping system, but the long-term effect needs further research.