[en] ²³⁷Np and Pu isotopes such as ²³⁹Pu and ²⁴⁰Pu in soil (three layers of core depth of 0-1 cm, 2-3 cm and 3-4 cm at C) and reservoir sediments (st. Y1∼Y3) collected around and in the Yamada-mae pond in Fukushima prefecture after the Fukushima Dai-ichi Nuclear Power Stations accident was reported. At C, Y1, Y2 and Y3, ²³⁷Np activities ranged from (0.060±0.01) to (0.50±0.04) mBq/kg-dry and these values were ∼2 orders of magnitudes low compared to those in environmental samples collected in Japan until 1980's, even considering radiation decay. ²³⁹Pu, ²⁴⁰Pu and ^239+240Pu activities ranged (14±2)∼(91±4) mBq/kg-dry, (17±2)∼(80±5) mBq/kg-dry, (24±3)∼(151±8) mBq/kg-dry, respectively and these values were also ∼2 orders of magnitude low compared to those before the FDNPS accident. ²³⁷Np/^239+240Pu activity ratio was (2.6±2)x10^-3∼(4.6±0.1)x10^-3 and ²⁴⁰Pu/²³⁹Pu atomic ratios were (0.18±0.01)∼(0.20±0.1). Both values were within range of global fallout (GF). ²³⁷Pu/²³⁹Pu atomic ratios were (0.37±0.02)∼(0.67±0.3) and the value at Y3 was higher compared to those at Y1 and Y2. From this study and last year reports, it is likely that ²³⁷Pu/²³⁹Pu atomic ratios between same deposition environments for catchment area were close values for few month scales. Moreover, it is suggested that very close values of ²³⁷Pu/²³⁹Pu at Y3 and C (0-1 cm layer) contributed input of terrestrial material due to heavy rain. In the future, it will need to verify these suggestions using more data and another approach. (author)