【摘要】 <正> 硼不属于剧毒物质,也不是国家《工业三废排放试行标准》中一、二类有害物质。硼作为作物生长发育所必需的一种微量元素,施用于缺硼的农田中,可使作物增产;而过量硼则会使作物中毒,产量降低,甚至对人畜健康有不利的影响。为了探明施用含硼污泥对农田土壤和作物污染的规律,并为拟订农用污泥中硼的控制标准提供依据,1980-82年在武昌进行了本试验。更多还原

【Abstract】 A research was conducted to establish the standard of the amount of boronin sludge used as manure by means of soil and water cultures with differentlevels of 0,2,……and 32ppm B; rice, wheat, and Chinese cabbage being usedas indicatoe plants. Following were some results of the experiment in the pastthree years. 1. An excess of boron obviously influenced the growth and yields ofcrops. The yields of wheat and rice tended to decline when 8ppm B wasapplied. The yield of Chinese cabbage was decreased by 12-18% with 12ppmB, and the yield of wheat and rice by 12% and 21. 97% respectively with16ppm B. There was no definite reduction of yields of the three crops tested,as boron toxic symptoms appeared. 2. Boron in sludge could be absorbed by crops and accumulated in everypart of plant. There was a regular pattern that for wheat the amount of bor-on in stem was higher than that in seed, but for rice the proportion of stemto seed in boron content was 1 approximately. The ability of absorbing boronby these two crops was similar. 3. Boron pollution in soils was evident. Only part of boron added to soliwas absorbed by crops and leached by rain and irrigation water. About 60-70%of boron remained in soil. 4. The effect of boron level on both the yield of crops and the remaind-er in soil should be mainly considered to set a limit to the maximum boroncontent in sludge. It is not allowed that boron level is beyond the limit of150 mg/kg if 2000kg of sludge is added per mu per year. In this ease the watersoluble boron will not exceed 5mg/kg during the next twenty years, and noserious pollution will be caused.更多还原