Carini F, Lombi E
Institute of Agricultural and Environmental Chemistry, Faculty of Agricultural Sciences, Università Cattolica del Sacro Cuore, Piacenza, Italy.
Sci Total Environ. 1997 Nov 27;207(2-3):157-64. doi: 10.1016/s0048-9697(97)00261-1.
The foliar and soil uptake of 134Cs and 85Sr by grape vines and their subsequent translocation to fruits and to the other plant compartments is described. Grape vine plants growing in pots and kept in an open field were contaminated with 134Cs and 85Sr in ionic form by sprinkling on the aerial part, or by addition to the soil. Sprinkling was effected at the stage of ripening of the grapes. Interception, determined by analysing all the leaves picked from three plants after the sprinkling, was approx. 50% of the sprayed activity. Soil contamination was effected after the fruit setting, 1 month earlier than sprinkling. At ripening, the whole plant was picked. Berries, leaves, shoots, stems, roots and soil were analysed by gamma spectrometry. Activities of the different parts of the plant were expressed as: (a) translocation factors of intercepted activity for foliar treatment; (b) transfer factors of activity applied to the soil for soil treatment. Both factors were calculated per unit of fresh weight, or referred to the total biomass of the plant compartment. Leaf-to-fruit translocation factors per unit of weight are of the order of magnitude of 10(-1) for 134Cs and of 10(-2) for 85Sr. One/two order of magnitude lower are soil-to-fruit transfer factors: 10(-3) both for 134Cs and for 85Sr. Radiocesium behaves quite differently from radiostrontium, but the behaviour of both radionuclides within the grape vine is independent of the path of absorption, by leaves or by roots. 134Cs is absorbed more easily than 85Sr by plant foliage, but is absorbed with more difficulty than 85Sr by roots. After absorption by either route, radiocesium concentrates mainly in the fruit compartment of the plant, whereas radiostrontium concentrates in the foliar compartment. Loss from the aerial part of the plant is higher for 85Sr than for 134Cs. 85Sr remains more available in soil than 134Cs, is more absorbed by roots and is more leached downward. After foliar contamination, the dominant pathway of radionuclides to reach the soil is by dislodging of non-absorbed radionuclides or senescent cells from the aerial part of the plant by action of wind and rain.
本文描述了葡萄植株对¹³⁴Cs和⁸⁵Sr的叶部吸收与土壤吸收情况，以及随后这些放射性核素向果实和植株其他部分的转移。将盆栽并置于露天场地的葡萄植株，通过向地上部分喷洒或向土壤中添加离子形式的¹³⁴Cs和⁸⁵Sr使其受到污染。喷洒在葡萄成熟阶段进行。通过分析喷洒后从三株植株上摘下的所有叶片来确定截留量，截留量约为喷洒活度的50%。土壤污染在坐果后进行，比喷洒提前1个月。在成熟时，采摘整株植株。通过γ能谱分析法对浆果、叶片、嫩枝、茎、根和土壤进行分析。植株不同部位的活度表示为：(a)叶部处理截留活度的转移因子；(b)土壤处理施加到土壤中活度的转移因子。这两个因子均按单位鲜重计算，或相对于植株部分的总生物量计算。¹³⁴Cs单位重量的叶到果转移因子数量级为10⁻¹，⁸⁵Sr为10⁻²。土壤到果的转移因子低一到两个数量级：¹³⁴Cs和⁸⁵Sr均为10⁻³。放射性铯的行为与放射性锶有很大不同，但两种放射性核素在葡萄植株内的行为均与吸收途径无关，无论是通过叶片还是通过根系吸收。¹³⁴Cs比⁸⁵Sr更容易被植物叶片吸收，但比⁸⁵Sr更难被根系吸收。通过任何一种途径吸收后，放射性铯主要集中在植株的果实部分，而放射性锶则集中在叶部。植株地上部分⁸⁵Sr的损失高于¹³⁴Cs。⁸⁵Sr在土壤中的有效性高于¹³⁴Cs，更容易被根系吸收且更容易向下淋溶。叶部污染后，放射性核素到达土壤的主要途径是通过风雨作用使未吸收的放射性核素或衰老细胞从植株地上部分脱落。
