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农作物是陆生食物链的重要环节,与人类的关系十分密切。粮食中某些元素的丰欠,往往影响人及动物的健康,甚至引起一定类型的疾病(地方病或公害病)。粮食的元素背景值,是评价农产品质量优劣、判断其是否受到污染以及评价污染程度的重要依据;也是评定区域环境质量、预测环境发展趋势、制定环境标准的基础资料;对某些地方性疾病病因和防病措施的研究亦有重要的参考价值。 植物体内的各种元素,尤其是大多数金属元素主要来源于土壤。土壤中或多或少都含有各种元素,但其含量是否适合某种作物的需要,其一决定于土壤中该元素含量的多寡,其二则决定于土壤的类型、性质和利用方式,决定于土壤中该元素可转换为植物利用状态的比率。加之众所周知的植物选择吸收作用的制约,所以,农作物元素含量既与土壤有关,受控于土壤类型和性质,又不是土壤元素含量的机械重复。与农业利用方式、耕作措施(包括耕耘、施肥等)、作物品种、以至其它环境要素(如水、大气等)的质量都有密切关系。因而,不同地区各种作物的元素含量存在一定差异,粮食元素背景值也只能是一个相对的概念。本文是指相对于我国东北中部地区自然环境和当今农业生产力水平情况下,粮食中某些矿质元素的含量水平。
Crops are an important part of the terrestrial food chain and have a very close relationship with humans. The abundance of certain elements in food often affects the health of people and animals and even causes certain types of diseases (endemic or pest-borne diseases). The background value of grain is an important basis for evaluating the quality of agricultural products, judging whether they are contaminated or not, and assessing the degree of pollution. It is also the basic information for assessing the regional environmental quality, predicting the trend of environmental development and setting environmental standards. For some endemic diseases Etiology and disease prevention measures also have important reference value. Various elements of plants, especially most of the metal elements are mainly derived from the soil. Soil contains more or less various elements, but its content is suitable for the needs of a crop, one depends on the amount of the element in the soil, and the other depends on the type, nature and utilization of the soil, the decision The rate at which the element can be converted to the state of plant utilization in the soil. Coupled with the well-known plant selection and absorption constraints, the crop element content is both soil-dependent and controlled by the type and nature of the soil and not the mechanical repeat of the soil elemental content. It is closely related to the quality of agricultural use, cultivation measures (including cultivation and fertilization, etc.), crop varieties and other environmental factors (such as water and air). Therefore, there are some differences in the contents of various crops in different regions, and the background value of food elements can only be a relative concept. This paper refers to the content level of some mineral elements in food relative to the natural environment in northeast of China and the level of agricultural productivity in our country today.