Genoni G P, Montague C L
Swiss Federal Institute for Environmental Science and Technology (EAWAG), Duebendorf.
Ecotoxicol Environ Saf. 1995 Mar;30(2):203-18. doi: 10.1006/eesa.1995.1025.
A concern of ecotoxicology is to predict to which trophic levels in biocenoses bioaccumulation of compounds or of elements occurs. Transformity, a measure of the energy required to produce and maintain a component or a flow resulting from an energy transformation process, may help predict bioaccumulation potential. This notion derives from two concepts. First, common substances are more likely to be processed by the biosphere. Moreover, the uptake of rare ones from the physical environment by organisms of low trophic levels makes them less unusual to organisms of high trophic levels, which may evolve a capability of processing them. Second, transformity expresses energy relationships between parts of a system. Substances that require more energy to form or concentrate are also the more unusual. The hypothesis was formulated that there is a correlation between the rarity, complexity, and energy required for concentrating a substance, and thus its transformity, and the transformity of the trophic level to which it bioaccumulates. This hypothesis was tested for a set of elements with published data on their biogeochemistry and bioaccumulation and on energy transfers between trophic levels in ecosystems. The transformities of the elements were calculated from the energy required by the biosphere for maintaining a difference in concentration compared to its physical environment. Transformities of corresponding trophic levels were calculated from the energy driving the energy flows. There was a significant rank correlation between the transformity of elements and that of trophic levels. This may be an important generalization in ecotoxicology because it may lead to the possibility of predicting bioaccumulation tendency.
生态毒理学关注的一个问题是预测化合物或元素在生物群落中的生物累积会发生在哪些营养级。转化值是衡量产生和维持能量转化过程中一个组成部分或一种流动所需能量的指标，它可能有助于预测生物累积潜力。这一概念源自两个理念。其一，常见物质更有可能被生物圈处理。此外，低营养级生物从物理环境中摄取稀有物质，使得这些物质对于高营养级生物来说不再那么罕见，高营养级生物可能会进化出处理它们的能力。其二，转化值表达了系统各部分之间的能量关系。形成或浓缩需要更多能量的物质也更为罕见。由此提出一个假设：物质的稀有性、复杂性以及浓缩所需能量之间存在关联，进而与它的转化值以及其生物累积所在营养级的转化值存在关联。针对一组元素对这一假设进行了检验，这些元素已有关于其生物地球化学、生物累积以及生态系统中营养级间能量转移的公开数据。元素的转化值是根据生物圈维持其与物理环境浓度差异所需的能量计算得出的。相应营养级的转化值是根据驱动能量流动的能量计算得出的。元素的转化值与营养级的转化值之间存在显著的等级相关性。这可能是生态毒理学中的一个重要概括，因为它可能带来预测生物累积趋势的可能性。
