Policy adjustment in crisis situations involves multidimensional changes in policy system elements.Previous studies have tended to focus on the overall relationship between crises and policy trends, neglecting to observe the fluctuations of policy system elements triggered by crises.This study draws on policy paradigm theory to extract observational elements, selecting environmental emergencies occurring between 2011 and 2020 for empirical research. Utilizing web crawlers to assemble a database of provincial ecological and environmental department policies, and employing supervised machine learning algorithms for automated coding, the study comparing the adjustments of policy system elements between normal and crisis periods based on statistical results. The results demonstrate that crisis events propel more substantial modifications in policy scale and instruments compared to normal conditions, with the magnitude of adjustments escalating in accordance with the severity of the crisis events. Nevertheless, policy objective adaptations predominantly manifest as dynamic fine-tuning of focal tasks, while crisis events do not incite policy objective adjustments surpassing conventional levels. The non-congruent shifts within the policy system can be encapsulated as "differentiated adaptation," underscoring the persistent tension and sequential metamorphosis between "change" and "stability" in policy systems under crisis circumstances. This offers a theoretical foundation for decoding the practicality of policies in effective risk management, and aids policymakers in focusing on balancing endogenous stability with exogenous conflicts, thereby promoting the maintenance of flexible adaptation and robust operation in policy implementation.

危机情境中的政策调适涉及政策系统要素的多维变动,既有研究重在笼统论述危机事件与政策走向的整体关系,疏于考察危机引致的政策系统内部波动。本文从政策范式理论提取观察维度,选取2011—2020年省级 “较大”和 “重大”突发环境事件开展具象研究,通过网络爬虫构建省级生态环境部门的政策数据库,利用监督机器学习算法进行自动编码,根据统计结果比较常态与危机时期的政策系统要素调整。研究发现危机事件驱动政策规模、政策工具的调整幅度高于常态水平,且调整幅度随危机事件等级提高而相应提升;政策目标调适多表现为对重点任务的动态微调,危机事件并未诱发政策目标调整幅度高于常态化水平。政策系统内部要素呈现的堕距性变动可概述为 “差异化调适”,其揭示了危机语境中政策要素存在 “变”与 “稳”的持续张力与序贯变换,为解码高效能风险治理的政策性应用提供了学理依据,有助于政策制定层注重平衡系统内生性稳定与外生性冲突,保持政策执行的灵活适应与稳健运行。