Strategic environmental assessment (SEA) aims to provide a sound theoretical basis on which to plan for biodiversity and ecosystem services (ES). With the multi-purpose and increasing use of SEA worldwide, it is timely to evaluate the effectiveness of SEA practice in integrating biodiversity and ES considerations. Here, we derive criteria from the International Best Practice Principles on Biodiversity and Ecosystem Services in Impact Assessment to evaluate six Australian SEAs conducted for urban development plans. We use qualitative and quantitative content analysis to examine the endorsed SEA reports. We identify and analyse text references related to the evaluation criteria and use word counting of keywords to supplement and cross-check the validity of our findings. Four significant results emerge from our analysis. First, while goals to achieve no net loss (NNL) or net gain outcomes for biodiversity are mentioned in all case studies, their poor specification may limit their effectiveness. Second, there is limited integration of ES considerations into the SEA reports, limiting the potential advantages that such an approach could provide. Third, offsetting is the most documented type of mitigation measure, potentially signalling a lack of evidence in implementing early steps of the mitigation hierarchy, including avoidance. This could be explained by the low level of integration of biodiversity and ES considerations from the early stages in the planning process, where there is more flexibility to apply such steps. Fourth, biodiversity management systems and follow-up activities lack detailed information to judge whether they will be useful to demonstrate NNL outcomes. Based on these findings, we present recommendations for enhancing the integration of biodiversity and ES considerations in SEAs. Our approach provides a general framework that can be applied to evaluate SEAs elsewhere in the world from a biodiversity and ES conservation perspective.

战略环境评估（SEA）旨在为规划生物多样性和生态系统服务（ES）提供良好的理论基础。随着SEA在全球范围内的广泛应用和日益广泛的使用，现在应该评估SEA做法在整合生物多样性和ES方面的有效性。在这里，我们从《影响评估中的生物多样性和生态系统服务国际最佳实践原则》中得出标准，以评估针对城市发展计划进行的六项澳大利亚策略性环境评估。我们使用定性和定量内容分析来检查认可的SEA报告。我们识别和分析与评估标准相关的文本参考，并使用关键字的字数统计来补充和交叉检查我们发现的有效性。我们的分析得出四个重要结果。第一，尽管在所有案例研究中都提到了不实现生物多样性净损失（NNL）或净收益结果的目标，但其目标不明确可能会限制其有效性。其次，将ES考虑因素整合到SEA报告中的机会有限，限制了这种方法可能提供的潜在优势。第三，抵消是最有据可查的缓解措施类型，有可能表明在实施缓解体系的早期步骤（包括避免）中缺乏证据。这可能是由于在规划过程的早期阶段，生物多样性和环境与社会考虑因素之间的融合程度较低，因此在实施此类步骤时具有更大的灵活性。第四，生物多样性管理系统和后续活动缺乏详细的信息来判断它们是否对证明NNL成果有用。基于这些发现，我们提出了有关在SEA中加强生物多样性和环境与社会考虑因素整合的建议。我们的方法提供了一个通用框架，可从生物多样性和ES保护的角度评估世界其他地区的SEA。