土壤环境基准是土壤环境质量标准制定的科学依据和基础。环境基准是土壤环境保护研究的前沿领域,涉及土壤环境化学、环境毒理学、生物学和风险评估等多学科交叉与基础性科学问题,了解和解决其所涉及的这些科学问题,是土壤环境基准研究的前提。本文针对土壤环境基准研究中影响重金属毒性阈值的非生物因子、生物因子、剂量-效应关系测定中等几个关键科学问题进行了阐述,包括土壤老化因子与淋洗因子的矫正,低剂量刺激效应拟合及毒性数据归一化方法等,最后以农田土壤Cd为例,推导出不同性质土壤中Cd环境基准(HC₅)及其与土壤性质的连续性分布曲线方程(LogHC₅=0.132pH+0.083OC+0.008CEC-1.448),以期为农田土壤环境指标基准的研究提供参考与借鉴。

Soil environmental benchmarks serve as the scientific cornerstone for establishing soil environmental quality standards. This cutting-edge field in soil environmental protection research encompasses interdisciplinary and foundational scientific issues such as soil environmental chemistry, environmental toxicology, biology, and risk assessment. Understanding and addressing these complex scientific challenges represent the forefront of soil environmental benchmark research. This article delves into several crucial scientific considerations that influence the toxicity thresholds of heavy metals in soil environmental benchmark research. These factors include non-biological elements, biological components, and the determination of dose-response relationships, encompassing the adjustment for soil aging and leaching factors, the modeling of low-dose stimulation effects, and methods for normalizing toxicity data. Furthermore, using Cd contamination in agricultural soil as a case study, this research establishes the Cd environmental benchmark (HC₅) for soils with varying properties. Equations based on cumulative distribution curves relating HC₅ values to soil properties are developed (e.g., LogHC₅=0.132pH+0.083OC+0.008CEC-1.448). The findings of this study are anticipated to offer valuable insights for the exploration of agricultural soil environmental indicators.