Land-use and -cover change (LUCC) is globally important to climate change mitigation. However, using land-based strategies to support aggressive subnational greenhouse gas emissions reduction targets is challenging due to competing land use priorities and uncertainty in ecosystem carbon dynamics and climate change effects. We used the California natural and working lands carbon and greenhouse gas model to quantify the direct ecosystem carbon emissions (CO₂ and CH₄) impacts, trade-offs, and climate change interactions of two policy scenarios identified by the State of California for fulfilling multiple land use goals, including the competing goals of mitigating wildfire severity and landscape carbon emissions, among others. Here we show that emissions from desired forest management to reduce the amount of combustible biomass (fuel reduction) initially outweighed emissions reductions from other strategies (e.g. less intensive forest management, restoration, land conservation); however, avoided emissions and enhanced carbon sequestration from the other strategies gradually outweighed fuel reduction emissions. Thus, in jurisdictions with large-scale wildfire mitigation goals, practices that reduce emissions and/or increase carbon sequestration can simultaneously offset fuel reduction emissions. Our analysis highlights the complexities inherent in LUCC planning, underscoring the need for governments to begin the task now.

土地利用和覆盖变化（LUCC）在全球范围内对缓解气候变化具有重要意义。但是，由于竞争性的土地使用优先级以及生态系统碳动态和气候变化影响的不确定性，使用陆基战略来支持积极的地方性温室气体减排目标具有挑战性。我们使用了加州自然和工作土地的碳和温室气体模型来量化直接的生态系统碳排放（CO ₂和CH ₄）加利福尼亚州确定的用于实现多种土地利用目标（包括减轻野火严重程度和景观碳排放的相互竞争目标）的两种政策方案的影响，权衡和气候变化的相互作用。在这里，我们表明，为减少可燃生物量（减少燃料）而进行的所需森林经营所产生的排放最初超过了其他战略所产生的减排量（例如，森林密集经营，恢复，土地保护）；但是，其他策略避免的排放和碳固存的增加逐渐超过了减少燃料的排放。因此，在具有大规模野火缓解目标的辖区中，减少排放和/或增加碳固存的做法可以同时抵消减少燃料的排放。