The invention discloses a method for detecting the biological enrichment microplastic degree of bivalve mollusks in a
deep sea extreme environment. According to the method, biocenosis is sampled to acquire a
community structure representing a biological
bed layer, then morphological characterization statistics is carried out to classify age stage data of
shellfish individuals, a multivariate
factor analysis method is used to obtain the
shellfish individuals with the largest contribution degree in each classification age stage, then tissue-divided micro-plastic extraction is carried out, and the classification age stage data of the
shellfish individuals with the largest contribution degree is obtained. The method comprises the following steps: reducing the form of
seabed micro-plastics, carrying out
process identification on full-size micro-plastics, tracing the duration of adsorbing the micro-plastics by each shellfish
monomer by virtue of a carbon-14 dating method, and constructing a
seabed shellfish dynamic enrichment curve by splicing the life of each shellfish; and finally amplifying to the whole shellfish
bed layer to deduce the microplastic enrichment rate and historical accumulation amount of the whole extreme
ecosystem. The method provides a scientific basis and a
technical support for formulating an effective marine environment protection strategy and clarifying a marine micro-plastic source-sink relationship.