Collaborative Research: Impacts of Climatic Change on the Boreal-Forest Fire Regimes of Alaska: Lessons from the Past and Prospects for the Future

合作研究：气候变化对阿拉斯加北方森林火灾状况的影响：过去的教训和未来的展望

• 批准号: 0612366
• 负责人: Feng Sheng Hu
• 金额: $ 54.82万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-06-15 至 2011-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0612366&HistoricalAwards=false
• 关键词: Collaborative; Research; Impacts; Climatic; Change

ABSTRACTHuOPP-0612366RuppOPP-0611970Intellectual Merit: Recent observations attest to the profound ecological and societal consequences of climatic change in northern high latitudes, including a doubling of area burned in the boreal forests of western North America in the past 30 years, attributed primarily to anthropogenic warming. Fire responses to climatic transients are not straightforward. A major unknown in predicting arctic-system behavior is how climatic change may alter boreal fire regimes, which has potential to overshadow the direct effects of anthropogenic warming on vegetational patterns, energy flux, and biogeochemical cycling. Boreal forests occupy ~80% of the Arctic Ocean watershed and the proportion is expanding as treelines advance in response to climatic warming. Increased occurrence of boreal-forest fires may have pervasive effects on hydrological, biophysical, and biogeochemical processes that exert key controls on the tightly coupled climate system of arctic and boreal regions. In addition, fire-regime shifts and associated vegetational changes will have profound consequences to the animals and northern cultures that make use of both arctic and boreal landscapes. This project confronts our poor understanding of fire responses to climatic change in arcto-boreal Alaska by integrating paleorecords and computer modeling. The centerpiece of the project is its innovative and rigorous approach to understand patterns and mechanisms of climate-firevegetation interactions from the recent geological past through the near future. Charcoal processes of contemporary and recent burns will be monitored to parameterize a new numerical model of charcoal-fire relationships (CharSiM), a tool that greatly enhances the rigor of fire-history reconstruction. The results will be applied to interpret fire histories of the past 6000 years (focusing on the neoglacial transition and oscillations within the Little Ice Age) from sediment-charcoal records. Sediment-charcoal data will be collected with statistical criteria in two study areas that are characterized by contrasting fire regimes and recent climate anomalies. The fire records will be compared with climatic and vegetational reconstructions using state-of-the-art paleoecological and geochemical techniques. An iterative paleodata-modeling approach will be applied to elucidate mechanistic processes of climate-vegetation-fire interactions (e.g., lead-lag relationship, fuel dynamics) using ALFRESCO, a model developed and well tested for studying Alaskan boreal ecosystems. Finally, the improved ALFRESCO will be used to simulate regional fire regimes for the next 100 years based on a suite of forecast climate scenarios. Each of the research elements represents the forefront of current research in the respective areas, and together they promise to substantially advance the understanding of fire-climate-vegetation relations for the past, present, and future.Broad Impacts: This project should bring new insights into the variability of boreal fire responses to climatic change and to improve the robustness of a key model for predicting future changes in boreal ecosystems. The prognostic simulations of the 21st century fire regimes will be directly relevant to fire management planning and policy. An outstanding minority doctoral student has been an integral part of the team during the pilot study. Students will receive interdisciplinary training and interact with a broad research community to gain an integrative perspective of global change study. In addition, the researchers will engage local residents in fieldwork and give informal lectures to local scientists and communities. The research is enthusiastically endorsed by the leaders of federal fire management units in Alaska who will be involved in the execution of this project and the dissemination of research products. Educational materials will be produced for outreach to the general public and for dissemination through visitor interpretive activities of the Alaska Fire Service, the US Fish and Wildlife Service, and the National Park Service.

摘要HuOPP-0612366RuppOPP-0611970智力成果：最近的观察证明了北部高纬度地区气候变化所产生的深远的生态和社会后果，包括过去30年北美西部北方森林烧毁面积翻了一番，这主要归因于人为变暖。火灾对气候瞬变的反应并不简单。预测北极系统行为的一个主要未知因素是气候变化如何改变北方火灾状况，这有可能掩盖人为变暖对植被模式、能量通量和生物地球化学循环的直接影响。北方森林占据了北冰洋流域约 80% 的面积，并且随着气候变暖而导致林线推进，这一比例正在扩大。北方森林火灾发生率的增加可能对水文、生物物理和生物地球化学过程产生普遍影响，这些过程对北极和北方地区紧密耦合的气候系统发挥关键控制作用。此外，火势变化和相关植被变化将对利用北极和北方景观的动物和北方文化产生深远的影响。该项目通过整合古记录和计算机建模，解决了我们对阿拉斯加北极北部气候变化火灾反应的了解不足的问题。该项目的核心是其创新和严格的方法，以了解从最近的地质过去到不久的将来气候与火灾植被相互作用的模式和机制。将监测当代和近期燃烧的木炭过程，以参数化新的木炭-火关系数值模型（CharSiM），这是一种大大提高火灾历史重建严谨性的工具。研究结果将用于根据沉积物-木炭记录解释过去 6000 年的火灾历史（重点是新冰期过渡和小冰河时期的振荡）。将按照统计标准在两个研究区域收集沉积物-木炭数据，这两个研究区域的特点是对比火情和近期气候异常。将使用最先进的古生态和地球化学技术将火灾记录与气候和植被重建进行比较。将使用迭代古数据建模方法来阐明气候-植被-火灾相互作用的机械过程（例如超前滞后关系、燃料动态），ALFRESCO 是一个为研究阿拉斯加北方生态系统而开发并经过充分测试的模型。最后，改进后的 ALFRESCO 将用于根据一系列预测气候情景模拟未来 100 年的区域火灾情况。每个研究要素都代表了各自领域当前研究的前沿，它们共同承诺将大大促进对过去、现在和未来火灾-气候-植被关系的理解。 广泛影响：该项目应该带来新的见解研究北方火灾对气候变化反应的可变性，并提高预测北方生态系统未来变化的关键模型的稳健性。 21 世纪火灾状况的预测模拟将与火灾管理规划和政策直接相关。试点期间，一名优秀的少数民族博士生成为了团队中不可或缺的一部分。学生将接受跨学科培训并与广泛的研究界互动，以获得全球变化研究的综合视角。此外，研究人员还将让当地居民参与实地考察，并向当地科学家和社区提供非正式讲座。该研究得到了阿拉斯加联邦消防管理单位领导人的热情支持，他们将参与该项目的执行和研究产品的传播。将制作教育材料以向公众宣传，并通过阿拉斯加消防局、美国鱼类和野生动物管理局以及国家公园管理局的游客解说活动进行传播。