摘要
所调查的23种蔬菜中,NO_3^-超过400ppm者占69％,不同种类蔬菜,同种蔬菜不同部位、不同生育期、不同季节,其NO_3^-累积量是不相同的,一般规律是:叶菜类(1267ppm)>葱蒜类(521ppm)>瓜果类(184ppm),肉质根、叶柄>叶部,生长前期>生长后期,冬季>春季,另外,施肥对蔬菜体内NO_3^-含量影响相当大,等氮量的有机肥比化肥更有利于降低蔬菜体内硝酸盐含量,最后探讨了土壤肥力水平与蔬菜硝酸盐含量的关系。
An inivestigation on twenty-three species vegetables of from 1987 to 1989 demonstrated that vegetables containing nitrate above 400ppm made up 69％ of the investigated,which implied that vegetables in Changsha and Xiangtan were polluted with nitrate severely,On the other hand,the nitrate content of vegetables varied with vegetable species.In order of decreasing nitrate coritent,they were foliage vegetable(1267ppm),onion and garlic(521ppm)and fruit vegetables(184ppm).The accummlation varying with tissues and growth periods in the same vegetable was also observed.Geneally,roots and stems contained more than leaves;and in earlier stage of growth than in latter stage.Besides,the nitrate content of vegetables in winter is 45％higher than that in spring.Farm-mariure was more effective than N-equivalent fertilizer in decreasing nitrate content in vegetables.The correlation betweern soil fertility and nitrate content in vegetables was also discussed.
关键词
蔬菜
硝酸盐
污染
长沙市
湘潭市
vegetable corps
nitrate
agricultural environment
pollution survey
Changsha
Hsingtan
