LTER: Long-Term Research on Grassland Dynamics- Assessing Mechanisms of Sensitivity and Resilience to Global Change

LTER：草地动态长期研究——全球变化敏感性和复原力评估机制

• 批准号: 1440484
• 负责人: Jesse Nippert
• 金额: $ 676.2万
• 依托单位: Kansas State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-11-01 至 2021-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1440484&HistoricalAwards=false
• 关键词: LTER; Long; Term; Research; Grassland

Grasslands cover more of the Earth's land than any other major vegetation type, and temperate grasslands are among the most endangered ecosystems on the planet. Threats to grasslands include land use changes, expansion of woody species, invasion by exotic species, and changes in climate and nutrient deposition. In the highly productive tallgrass prairies of North America, changes in fire, grazing and climate are especially critical. Conserving the biological diversity and ecosystem services provided by these grasslands, while also managing them for sustainable production, requires a comprehensive understanding of how these ecosystems will respond to current and future environmental and land-use changes. Decades of research at the Konza Prairie LTER site are producing a rich and detailed understanding of how environmental and land-use changes independently and interactively affect the structure and function of grasslands and associated groundwater and streams. New research will build on this foundation of long-term experiments and measurements to understand causes and consequences of ecological change in tallgrass prairie. This will contribute to the sustainable management, conservation and, restoration of terrestrial and aquatic resources in tallgrass prairies, and other grasslands globally. Research on restoration of grasslands is particularly timely because of the widespread loss and degradation of prairies and other grasslands. The impacts of Konza Prairie research will extend far beyond the site, through engagement with stakeholders and management and conservation agencies. Researchers will disseminate findings through the Flint Hills Discovery Center, which educates civic, professional, conservation, and governmental agencies about the tallgrass prairie and the Flint Hills region of Kansas. The Konza Environmental Education Program will engage over 1,000 school students annually in hand-on science education activities. The Konza LTER program will conduct an annual Summer Teacher's Workshop provides to train elementary and secondary teachers, and a summer field biology course at a local high school. The project will support community education through collaboration with the Kansas Association for Conservation and Environmental Education, Flint Hills Discovery Center, Manhattan Boys and Girls Club, and United School District 383. The research is organized around four major themes (land-use change, climatic variability, altered biogeochemical cycles, and restoration ecology) and builds on a 30-yr foundation of long-term experiments and measurements in terrestrial and aquatic grassland ecosystems. Watershed- and plot-level experiments at Konza Prairie have altered fire, grazing, climate, nutrient availability in ways that have created a range of different ecological states and legacies. New research will couple ongoing long-term observations and experiments with new studies to (1) test and refine conceptual and theoretical models of community and ecosystem change, and (2) provide new insights into the mechanisms underlying ecological responses to critical environmental and land-use changes. This research will a) measure responses to long-term manipulation of fire, grazing, climate, and nutrients, b) test novel causative factors in additional experiments, c) determine the ability of bison grazing to develop and maintain alternate stable vegetation states, and d) cease or alter some long-term experimental manipulations (water or nutrient availability) to assess ecological legacy effects and feedbacks. Fire and grazing studies will address fundamental questions regarding top-down and bottom-up controls of ecological processes, and effects of heterogeneity on biodiversity and ecosystem processes. Studies of woody plant encroachment, climate change, and chronic N enrichment will address three of the most critical changes occurring in grasslands worldwide. Researchers will use intermediate fire return treatments too ask whether observed shrub encroachment under intermediate fire intervals represents a new stable state. Restoration studies will test fundamental ecology theories on controls of plant diversity and community assembly, while building a foundation for more effective strategies for restoring grasslands and conserving grassland biodiversity. This research is conceptually integrated through a common theme of sensitivity and resilience of grasslands to natural and anthropogenically-altered drivers. When these diverse and creative research projects are taken together, this long-term project is poised to address major global change phenomena and to test fundamental ecological theory related to non-linear dynamics and alternate stable states, productivity-diversity and disturbance-stability relationships, top-down vs. bottom-up regulation of ecological processes, food web dynamics, and responses to environmental heterogeneity.

草原覆盖地球的土地比任何其他主要植被类型都要多，温带草原是地球上最濒危的生态系统之一。对草原的威胁包括土地利用变化，木质物种的扩张，外来物种的入侵以及气候和养分沉积的变化。在北美高生产力的高草大草原中，火灾，放牧和气候的变化尤其重要。保护这些草原提供的生物多样性和生态系统服务，同时还需要将它们进行可持续生产管理，需要对这些生态系统如何应对当前和未来的环境和土地利用变化做出全面了解。 Konza Prairie lter网站上的数十年研究对环境和土地利用如何独立和交互影响草地以及相关的地下水和溪流的结构和功能进行了丰富而详细的了解。新的研究将基于这一长期实验和测量的基础，以了解塔格拉斯草原生态变化的原因和后果。这将有助于可持续的管理，保护以及塔格拉斯大草原和其他草原的陆地和水生资源的恢复。关于草原恢复的研究尤其及时，因为大草原和其他草原的普遍损失和退化。通过与利益相关者以及管理和保护机构的交往，Konza Prairie Research的影响将远远超出现场。研究人员将通过Flint Hills Discovery Center传播发现，该发现中心对塔格拉斯草原和堪萨斯州的弗林特山地区进行教育，专业，保护和政府机构的教育。 Konza环境教育计划每年将参与1,000多名学校学生的科学教育活动。 Konza lter计划将举办年度夏季教师的研讨会，以培训小学和中学教师，并在当地一所高中进行夏季野外生物学课程。该项目将通过与堪萨斯州保护与环境教育协会，弗林特山发现中心，曼哈顿男孩和女孩俱乐部以及联合学区383的合作来支持社区教育。这项研究是围绕四个主要主题（土地利用变化，气候变化，生物地球化学周期改变的30层面的生物学生态学）以及远程衡量的30层基础的研究组织。生态系统。 Konza Prairie的分水岭和情节水平实验改变了火灾，放牧，气候，营养供应，从而创造了一系列不同的生态状态和遗产。新的研究将持续的长期观察和实验与新研究相结合，以（1）测试和完善社区和生态系统变化的概念和理论模型，（2）对对关键环境和土地利用变化的生态反应的基本机制提供新的见解。这项研究将a）衡量对对火，放牧，气候和营养的长期操纵的反应，b）在其他实验中测试新的病因因素，c）确定野牛放牧开发和维护替代稳定植被状态的能力，d）停止或停止或改变一些长期实验操作（水或营养可用性（水或营养可用性），以评估生态效果和生态效应。火灾和放牧研究将解决有关生态过程自上而下和自下而上控制的基本问题，以及异质性对生物多样性和生态系统过程的影响。对木本植物侵占，气候变化和慢性N富集的研究将解决全球草原发生的三种最关键的变化。研究人员也将使用中间消防治疗，询问在中间火力间隔下观察到的灌木侵占是否代表了一种新的稳定状态。恢复研究将测试有关植物多样性和社区集会控制的基本生态学理论，同时为更有效的策略恢复草地和保护草地生物多样性。这项研究在概念上是通过对天然和人为改变驱动因素的敏感性和韧性的共同主题来整合的。当将这些多样化和创意的研究项目共同完成时，该长期项目将有助于解决全球重大变化现象，并测试与非线性动态和替代稳定状态，生产力多样性和干扰稳定性关系有关的基本生态学理论，自上而下的生产力多样性和对生态过程，食品网络动力学的自下而上的调节，以及对环境异质性的反应。