Alberta Biodiversity Monitoring Institute, University of Alberta, CW 405 Biological Sciences Building, Edmonton, Alberta, T6G 2E9, Canada; Department of Biological Sciences, University of Alberta, CW 405 Biological Sciences Building, Edmonton, Alberta, T6G 2E9, Canada.
Conserv Biol. 2013 Dec;27(6):1313-23. doi: 10.1111/cobi.12098. Epub 2013 Jul 21.
The commonly expressed goal of biodiversity offsets is to achieve no net loss of specific biological features affected by development. However, strict equivalency requirements may complicate trading of offset credits, increase costs due to restricted offset placement options, and force offset activities to focus on features that may not represent regional conservation priorities. Using the oil sands industry of Alberta, Canada, as a case study, we evaluated the economic and ecological performance of alternative offset systems targeting either ecologically equivalent areas (vegetation types) or regional conservation priorities (caribou and the Dry Mixedwood natural subregion). Exchanging dissimilar biodiversity elements requires assessment via a generalized metric; we used an empirically derived index of biodiversity intactness to link offsets with losses incurred by development. We considered 2 offset activities: land protection, with costs estimated as the net present value of profits of petroleum and timber resources to be paid as compensation to resource tenure holders, and restoration of anthropogenic footprint, with costs estimated from existing restoration projects. We used the spatial optimization tool MARXAN to develop hypothetical offset networks that met either the equivalent-vegetation or conservation-priority targets. Networks that required offsetting equivalent vegetation cost 2-17 times more than priority-focused networks. This finding calls into question the prudence of equivalency-based systems, particularly in relatively undeveloped jurisdictions, where conservation focuses on limiting and directing future losses. Priority-focused offsets may offer benefits to industry and environmental stakeholders by allowing for lower-cost conservation of valued ecological features and may invite discussion on what land-use trade-offs are acceptable when trading biodiversity via offsets. Resultados Económicos y Ecológicos de Sistemas de Compensación de Biodiversidad Flexible Habib et al.
生物多样性补偿的普遍目标是实现受发展影响的特定生物特征的净损失为零。然而，严格的等效性要求可能会使补偿信用额的交易变得复杂，增加由于受限的补偿安置选择而导致的成本，并迫使补偿活动集中在可能不代表区域保护重点的特征上。我们以加拿大艾伯塔省的油砂产业为例，评估了针对生态等效区域（植被类型）或区域保护重点（北美驯鹿和干混交林自然亚区）的替代补偿系统的经济和生态绩效。交换不同的生物多样性元素需要通过一般化指标进行评估；我们使用生物多样性完整性的经验衍生指数将补偿与发展造成的损失联系起来。我们考虑了两种补偿活动：土地保护，成本估计为石油和木材资源的净现值，作为对资源所有权持有者的补偿；以及人为足迹的恢复，成本根据现有恢复项目进行估计。我们使用空间优化工具 MARXAN 来开发符合等效植被或保护重点目标的假设性补偿网络。需要补偿等效植被的网络成本比重点保护网络高出 2-17 倍。这一发现质疑了基于等效性的系统的谨慎性，特别是在相对欠发达的司法管辖区，这些地区的保护重点是限制和指导未来的损失。以保护重点为导向的补偿可能为行业和环境利益相关者带来益处，允许以较低的成本保护有价值的生态特征，并可能引发关于通过补偿进行生物多样性交易时可以接受哪些土地利用权衡的讨论。
