Institute of Soil and Water Resources and Environmental Science, Zhejiang University, Hangzhou 310029, China.
Chemosphere. 2010 Jan;78(3):335-41. doi: 10.1016/j.chemosphere.2009.10.023. Epub 2009 Nov 10.
A laboratory study was conducted to investigate the mineralization of metsulfuron-methyl (MSM) in paddy soils in response to soil moisture, temperature and soil properties. The results indicated that MSM mineralization was relatively limited in the paddy soils when soil temperature was low. Only 2.2-6.0% of the applied (14)C mineralized after 84d of incubation at 15 degrees C. The mineralization of MSM was enhanced by increasing soil moisture and soil temperature. Soil moisture would have different impact on the response of MSM mineralization to variation in soil temperature. An increase of 10 degrees C accelerated the average rate of MSM mineralization by 2.3 times at 50% water-holding capacity (WHC) and 1.9 times at 40% WHC. Regression analysis showed that soil pH, organic carbon contents, microbial biomass carbon contents, and silt/clay fractions were the dominant factors affecting MSM mineralization, with pH as the most important factor. The relatively slow mineralization rate of MSM suggested long persistence of this herbicide in soil, thus increasing its potential ecological risk, especially when applied in alkaline soils and in cold areas.
一项实验室研究调查了土壤水分、温度和土壤特性对稻田中甲磺隆（MSM）矿化的影响。结果表明，当土壤温度较低时，稻田中 MSM 的矿化作用相对有限。在 15°C 下培养 84 天后，仅 2.2-6.0%的施用 （14）C 矿化。通过增加土壤水分和土壤温度可以增强 MSM 的矿化作用。土壤水分会对 MSM 矿化对土壤温度变化的响应产生不同的影响。在 50%持水量（WHC）和 40%WHC 时，土壤温度升高 10°C 可分别将 MSM 矿化的平均速率提高 2.3 倍和 1.9 倍。回归分析表明，土壤 pH 值、有机碳含量、微生物生物量碳含量和粉粒/粘粒分数是影响 MSM 矿化的主要因素，其中 pH 值是最重要的因素。MSM 矿化速度相对较慢表明该除草剂在土壤中具有较长的持久性，从而增加了其潜在的生态风险，尤其是在碱性土壤和寒冷地区应用时。
