Plutonium (Pu) interactions in the environment are highly complex. Site-specific variables play an integral role in determining the chemical and physical form of Pu, and its migration, bioavailability, and immobility. This paper aims to identify the key variables that can be used to highlight regions of radioecological sensitivity and guide remediation strategies in Australia. Plutonium is present in the Australian environment as a result of global fallout and the British nuclear testing program of 1952–1958 in central and west Australia (Maralinga and Montebello islands). We report the first systematic measurements of ^239+240Pu and ²³⁸Pu activity concentrations in distal (≥1000 km from test sites) catchment outlet sediments from Queensland, Australia. The average ^239+240Pu activity concentration was 0.29 mBq.g ⁻¹ (n = 73 samples) with a maximum of 4.88 mBq.g ⁻¹.²³⁸Pu/^239+240Pu isotope ratios identified a large range (0.02–0.29 (RSD: 74%)) which is congruent with the heterogeneous nuclear material used for the British nuclear testing programme at Maralinga and Montebello Islands. The use of a modified PCA relying on non-linear distance correlation (dCorr) provided broader insight into the impact of environmental variables on the transport and migration of Pu in this soil system. Primary key environmental indicators of Pu presence were determined to be actinide/lanthanide/heavier transition metals, elevation, electrical conductivity (EC), CaO, SiO₂, SO₃, landform, geomorphology, land use, and climate explaining 81.7% of the variance of the system. Overall this highlighted that trace level Pu accumulations are associated with the coarse, refractive components of Australian soils, and are more likely regulated by the climate of the region and overall soil type.

环境中的（（Pu）相互作用非常复杂。特定于站点的变量在确定Pu的化学和物理形式及其迁移，生物利用度和固定性方面起着不可或缺的作用。本文旨在确定可用于突出显示放射生态敏感性区域并指导澳大利亚修复策略的关键变量。由于全球影响以及英国在1952至1958年在澳大利亚中部和西部（马拉林加岛和蒙特贝罗群岛）进行的核试验计划，in在澳大利亚的环境中存在。我们报告了澳大利亚昆士兰州（距测试地点≥1000km）远侧集水口沉积物中^{239 + 240} Pu和²³⁸ Pu活性浓度的首次系统测量。平均^{239 + 240}Pu活性浓度为0.29mBq.g ^-1（n ＝ 73个样品），最大为4.88mBq.g ^-1。²³⁸ Pu / ^{239 + 240} Pu同位素比确定了很大的范围（0.02-0.29（RSD：74％）），这与用于马拉林加岛和蒙特贝罗群岛的英国核试验计划的异质核材料是一致的。依赖于非线性距离相关性（dCorr）的改良PCA的使用为环境变量对土壤中Pu的迁移和迁移的影响提供了更广泛的见识。确定Pu存在的主要关键环境指标为act系元素/镧系元素/重过渡金属，高程，电导率（EC），CaO，SiO ₂，SO ₃，地貌，地貌，土地利用和气候，解释了系统变化的81.7％。总的来说，这表明痕量的Pu积累与澳大利亚土壤的粗糙，折射成分有关，并且更可能受到该地区的气候和整体土壤类型的调节。