环境与基因型互作对瓜类蔬菜镉积累的影响及产地土壤安全阈值研究OA北大核心CSTPCD

The current situation of cadmium(Cd)contamination in farmland soils is severe,leading to an increased risk of Cd intake by the public through vegetable consumption.However,research on the characteristics of Cd accumulation in cucurbit vegetables under different soil contamination conditions and genotypes remains insufficient.To investigate the Cd absorption and accumulation characteristics of different cucurbit vegetable varieties under various environmental conditions and evaluate the combined effects of environmental factors and cucurbit genotypes,vegetable Cd content,soil Cd content,and soil physicochemical properties were collected from 12 typical cadmium-contaminated areas in the Xiangjiang River Basin,and adopting a multi-point,multi-species/variety field experiment method.Correlation analysis,stepwise linear regression analysis,and species sensitivity distribution(SSD)of multiple distribution models were employed to explore the relationship between environmental factors,Cd content,bioconcentration factor(BCF),and the soil safety threshold in cucurbit vegetables.The results showed the following:1)The influence of environmental factors on Cd content in cucurbit vegetables was significantly stronger than that of genotypes,and the environment,variety,and environment-variety interaction explained 94.05%and 84.03%of the Cd content and BCF of cucurbit vegetables,of which the contribution of the environment was 62.90%and 36.67%,respectively.2)The Cd content of cucurbit vegetables was significantly positively correlated with total soil Cd and available Cd(r=0.721,p≤0.01;r=0.737,p≤0.01)and was significantly negatively correlated with pH(r=-0.390,p≤0.01).Soil available Cd concentration and pH were the main influencing factors,explaining 60.80%of the variation in Cd content in cucurbit vegetables.3)The overall risk of exceeding the standard for cucurbit vegetables is low,but there was a significant difference in Cd enrichment capabilities among different varieties,with chestnut pumpkin(Cucurbita moschata)V5 showing high sensitivity,whereas honey pumpkin V6 showed low sensitivity.4)Based on the Burr type III distribution model,it was estimated that the soil Cd threshold 1.316 mg∙kg⁻¹ could ensure safe produce of 95%of cucurbit vegetable varieties.This study provides scientific guidance for variety selection and risk control in the cultivation of cucurbit vegetables in Cd contaminated soils.