LTER: Comparative Study of a Suite of Lakes in Wisconsin

世界各地的淡水湖提供了重要的生态和人类利益，从水生栖息地到体育和商业渔业，再到安全可靠的饮用水。北温带湖泊（NTL）长期生态研究计划的目标是了解湖泊如何以及为什么随着时间的推移而变化，并确定这些变化对这些和其他基本服务的影响。这项研究的重点是两组湖泊及其周围的景观。其中一组位于威斯康辛州北部的乡村、森林和以游客为主的北部高地湖区，另一组位于威斯康辛州首府麦迪逊附近的农业和城市景观。通过对这些对比环境的研究，我们可以深入了解不同景观和地区的单个湖泊和湖泊群是如何受到气候变化、大型风暴事件、入侵物种、有害藻华、城市化和环境政策变化等现象的影响的。该项目实施了许多不同的方法来收集长期数据并分析这些长期观察结果。研究结果提高了人们对湖区生态变化的认识，这对任何关注特定地区未来、淡水资源和居民福利的人都很重要。结果还被纳入多种教育和培训活动。NTL计划致力于支持科学多样性，并致力于向广大受众传播科学发现和专业知识，向个人、非政府组织、学术界以及地方、州和联邦机构提供信息。该项目将解决生物物理环境、气候、土地利用和覆盖如何在过去、现在和未来相互作用，塑造湖泊动态和组织的首要问题。将在主题领域组织活动，包括(1)记录、描述和解释湖泊和湖区的长期变化；(2)探索过去和潜在的未来气候条件如何影响湖泊的物理、化学和生物过程；(3)了解湖泊内部和湖泊之间长期变化的空间变化机制和原因；(4)研究湖泊和湖区如何应对突发变化、极端事件或相互作用的驱动因素。这项工作涉及景观生态学、干扰生态学和多重因果关系的概念和模型。将在一系列尺度和主题上解决问题，包括湖内热状态的变化和鱼类栖息地对气候的响应，湖泊间水生入侵物种的丰度-影响关系；流域有机碳和磷的动态，区域水的清澈趋势，以及许多其他的。研究方法包括生成和分析长期观测、实验、多个湖泊的比较研究，以及各种建模和统计工具。研究小组由生物地球化学、气候学、古湖泊学、人口学、生态学（景观、生态系统、群落、人口和古生态学）、经济学、教育和推广、水动力学、水文学、信息管理和微生物学等跨学科的专家组成。多尺度、多层面的NTL研究项目旨在检测长期变化的模式，评估和推进概念，以了解这些变化的原因和后果，并建立前瞻性模型和假设，这些模型和假设将使用未来的长期观察进行测试。

Freshwater lakes around the world provide essential ecological and human benefits that range from aquatic habitat to sport and commercial fisheries to safe and reliable drinking water. The goal of the North Temperate Lakes (NTL) Long-Term Ecological Research Program is to understand how and why lakes change over time and to determine the consequences of these changes for these and other basic services. The research focuses on two sets of lakes and their surrounding landscapes. One set lies in the rural, forested, and tourist-dominated Northern Highland Lake District in northern Wisconsin and the other lies in the agricultural and urban landscape around Madison, Wisconsin's capitol. Studies of these contrasting settings provide insights into how individual lakes and groups of lakes across landscapes and regions are affected by phenomena such as shifting climate conditions, large storm events, invasive species, harmful algal blooms, urbanization, and changes in environmental policies. The project implements a number of different approaches to collect data over long time periods and to analyze these long-term observations. Results improve understanding of ecological change in lake districts that is important to anyone concerned with the future of a particular region, its freshwater resources, and the welfare of its residents. Results are also integrated into multiple educational and training activities. The NTL program is committed to supporting diversity in science, and to outreach efforts that communicate scientific findings and expertise to broad audiences, informing individuals, non-governmental organizations, academics, and local, state and federal agencies. The project will address the overarching question of how biophysical setting, climate, and land use and cover interact to shape lake dynamics and organization in the past, present and future. Activities will be organized in thematic areas that involve (1) documenting, describing, and interpreting long term change in lakes and lake districts; (2) exploring how past and potential future climate conditions influence lake physical, chemical, and biological processes; (3) understanding how and why long-term changes vary spatially within and among lakes; and (4) examining how lakes and lake districts respond to sudden changes, extreme events, or interacting drivers. The work informs and is informed by concepts and models from landscape ecology, disturbance ecology, and multiple causation. Questions will be addressed across a range of scales and topics, including within-lake changes in thermal regime and fish habitat in response to climate, abundance-impact relationships for aquatic invasive species among lakes; watershed organic carbon and phosphorus dynamics, regional water clarity trends, and many others. Research approaches include generating and analyzing long-term observations, experiments, comparative studies of multiple lakes, and diverse modeling and statistical tools. The research group comprises an interdisciplinary team with expertise in biogeochemistry, climatology, paleolimnology, demography, ecology (landscape, ecosystem, community, population, and paleo- ecology), economics, education and outreach, hydrodynamics, hydrology, information management, and microbiology. The multi-scale, multi-faceted NTL research program is designed to detect patterns of long-term change, evaluate and advance concepts to understand causes and consequences of these changes, and build forward-looking models and hypotheses that will be tested using future long-term observations.