Giving a scientific and reasonable methods of monitoring and evaluation of soil cadmium pollution and its remediation effect, is a vital topic in the field of phytoremediation. Present studies were conducted to explore a new bio-monitoring method which was applied to Cd pollution evaluation, based on the sensitive reaction characteristics ofPogonatum inflexum under Cd stress. Soils were used as culture substrate with low background values of Cd, and gradient concentrations of Cd were set and here are the results as follows: (1) Appearance of the sporophyte and gametophyte ofPogonatum inflexum showed significant changes within a short time while the Cd concentrations in soil greater than 2~3 mg·kg-1, and the leaflets of the tested plants fell victim deeper until turn to etiolation or browning along with the Cd pollution level increased, and the plants were withered dead under 5 mg·kg-1 of Cd treatment. (2) The chlorophyll content of the plants affected by Cd pollution obviously and responsively, especially as the concentration of Cd was greater than 3 mg·kg-1, reduced more than three-quarters ultimately and exerted rapid response to the processing time of treatment. (3) The soluble protein and MDA content of the plants for test showed the same characteristics under Cd stress, and the change rate obviously speeds up at ending. (4) The above-mentioned three kinds of physiological parameters(that is chlorophyll, soluble protein and MDA)could be suitable for indicating bioavailability and reflecting safety standards of Cd in soil. (5) ThePogonatum inflexum could be used as an ideal plant materials because of the quicklook symptoms under the poisonous effect of Cd, due to the strong ability of induction of rhizoids in Cd contaminated soil.%如何利用较为科学、合理的技术方法，对土壤中的镉污染及其修复效果进行监测与评价，是植物修复土壤镉污染实际操作中存在的重要问题。该研究基于东亚金发藓（Pogonatum inflexum）对镉的敏感性反应特征，初步探索一种适用于土壤镉污染的生物监测方法。以含镉背景值相对较低的土壤作为栽培基质，采用梯度质量分数镉胁迫的方式进行研究，结果表明，（1）当土壤中的镉质量分数大于2~3 mg·kg-1时，东亚金发藓植株孢子体和配子体的外观形态在短时间内呈现出显著变化特征；随镉质量分数的增加和时间的延长，小叶受害程度加深，出现黄化或褐变现象，测定期内5 mg·kg-1的镉处理最终可使植株枯亡。（2）叶绿素含量受镉胁迫影响显著，且对镉胁迫时间反应较为迅速：2 mg·kg-1以内的镉处理下，叶绿素含量在7 d中的变化均不大；镉质量分数大于3 mg·kg-1时，对叶绿素含量影响显著，且随时间延长叶绿素下降程度更加明显；4 mg·kg-1的镉处理可使叶绿素含量下降3/4以上。（3）镉胁迫导致植物体内可溶性蛋白含量显著降低，处理初期可溶性蛋白含量变化不大，后期则变化明显，可导致蛋白含量减少40%~50%；同时细胞膜脂过氧化作用显著增强（表现为 MDA 浓度上升）， MDA含量增加了1.8倍以上。（4）东亚金发藓叶绿素含量、可溶性蛋白含量及MDA含量等生理参数的变化，可有效指示土壤中镉的生物有效性，并能反映土壤镉安全浓度标准。（5）东亚金发藓的假根对土壤中的镉具有较强的感应能力，植株易受到镉离子毒害并快速、直观地表现出一系列症状，因此可作为有效监测土壤镉污染的理想植物材料。
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