关键词: 蔬菜, 蔬菜, 农药残留, 检出率

Abstract: In order to accurately forecast heavy snow in Shanxi , provide more fine service for agriculture production, and meet disaster prevention and reduction and government decision, the author choose three heavy snow caused by reflow and inverted rough such as February 9th-10th, 25th-28th,2011, and March 14th-15th,2010, using various sounding data, comprehensively comparative analysis snow characteristic, circulation situation and its configuration, physical quantity characteristic, and their difference. The results showed that: (1) Due to the difference among circulation configuration, transfer characteristic of water vapor, and dynamical and thermal structure characteristic, there are much difference among snow intensity, area, and time of duration. (2) In the process of three heavy snow, there are three mesoscale structures such as mesoscale shear, mesoscale vortex, and mesoscale convergence which have great difference of snow characteristic. (3) There are three cloud types such as high-level trough cloud transit, cloud development after trough, and frontal cloud system. Change of TBB and increase of water content In the upper troposphere have Indicative significance for forecast of heavy snow. So, it is important way for fine forecast of this snow that fully understand these characteristics and their difference, and abstract key technical indicator of forecast.