The invention provides a root box for submerged
plant cultivation and
rhizosphere microcell DGT test and a use method thereof. Two filter screens are adopted for separating an inner chamber of a box body of the root box into a lower layer chamber, a middle layer chamber and an upper layer chamber which are arranged in turn from bottom to top; the roots of the submerged
plant are cultivated in the middle layer chamber; the
rhizosphere microcell sediments and the rootless sediments are effectively and obviously separated; and meanwhile, a test port, through which DGT and
sediment sampler can pass, is formed on a side wall of the middle layer chamber; the in-situ and accurate determination of DGT for the elements, such as
phosphorus, in the process of migrating on a
plant root /
sediment interface can be realized; complete
plant root characteristics can be acquired. The root box provided by the invention has the advantages that the structure is simple, the
survival rate of the plants is high and the root box can be used for evaluating the bio-availability of the elements such as
phosphorus. According to the use method of the root box provided by the invention, the cultivation for submerged plant and the in-situ test for
rhizosphere microcell DGT can be realized at the same time, the operation is simple and convenient, and the use method can be easily large-scale popularized.