Long-Term Ecological Research at the H.J. Andrews Experimental Forest (LTER5)

安德鲁斯LTER项目旨在了解太平洋西北部森林和河流生态系统的长期动态。指导Andrews LTER研究的核心问题是：土地利用、自然干扰和气候变化如何影响三组关键的生态系统服务：碳和营养动态、生物多样性和水文？这些生态系统服务代表了科学和社会上重要的、可处理的变量，它们的响应被认为代表了景观尺度上不同类别的生态系统行为。气候、土地利用和自然干扰是太平洋西北地区变化的主要驱动因素。用于解决这个问题的方法将是多方面的，包括回顾性分析，时间序列观察，实验，以及使用模拟模型进行综合，时间外推和空间内插。LTER研究的主要空间尺度是安德鲁斯森林和邻近的蓝河上游流域，面积为16,000公顷。与LTER有关的工作将与针对区域问题的研究相协调。提出的LTER研究的主要时间范围跨越了过去500年和未来几个世纪。该提案代表了旨在推进单个学科、整合和跨站点比较的科学活动的战略计划。因此，安德鲁斯LTER被用作一组更大的综合研究的核心。将继续进行必要的长期研究，并增加其他研究以增加尺度的空间和时间重叠。标准的5个LTER核心活动将通过七个组成领域的工作来解决：(1)气候，(2)水文，(3)干扰，(4)生态生理学，(5)碳和营养动力学，(6)生物多样性，(7)河流-森林相互作用。在这一资助周期中，研究将继续研究变化驱动因素与响应过程和分类群之间的相互作用，但概念重点将放在生态系统变化的时间行为、其原因及其后果上。我们将在数天到数百年的时间尺度上研究时间行为，重点关注：(1)调制，(2)时间滞后，(3)空间相干，(4)路径依赖，(5)滞后，(6)可选稳定状态。探索时间行为的这些方面有助于通过量化自然的时间变异性来解决核心问题，并提供对控制过程的机制的见解。一个主要目标将是测试调节时间行为的预测规则（即假设）。综合的另一个重点将是小流域，这是一个重要的景观单元，为气候、生态系统和水文过程的整合以及时空尺度的知识提供了机会。这一整合的最终目标是创建一个空间三维（包括地下和空气流动）对流域内生物地球化学和水文循环中涉及的物质的三种状态的时间动态的理解。过去的实验、气候、水流、养分输出和植被变化的长期记录以及建模将加强这种整合工作。通过了解这一关键景观单元，未来将加强更广泛的努力。安德鲁斯大学的科学和科学家们通过与学生、教师、政策制定者、土地管理者和公众的交流，继续推进对太平洋西北地区森林和河流的理解和管理。信息管理是研究和教育的一项重要活动，它强调多种形式信息的易用性、可访问性和可移植性。

Harmon0218088The Andrews LTER program seeks to understand the long-term dynamics of forest and riverecosystems of the Pacific Northwest. The Central Question guiding Andrews LTER research is:How do land use, natural disturbances, and climate change affect three key sets ofecosystem services: carbon and nutrient dynamics, biodiversity, and hydrology? Theseecosystem services represent scientifically and socially important, tractable variables, and theirresponses are posited to represent different classes of ecosystem behavior at the landscape scale.Climate, land use, and natural disturbances are the major drivers of change in the PacificNorthwest region. The approach used to address this question will be multi-faceted involvingretrospective analysis, time series observations, experiments, and use of simulation models forsynthesis, extrapolation in time, and interpolation in space. The principal spatial scale ofinference for LTER studies is the Andrews Forest and adjacent upper Blue River watershed, anarea of 16,000 ha. Work associated with the LTER will be coordinated with studies aimed atregional questions. The principal temporal extent of proposed LTER studies spans the past 500yr and to several centuries projected into the future. This proposal represents the strategic plan ofactivities designed to advance science for individual disciplines, integration, and cross-sitecomparisons. Thus, the Andrews LTER is used as the core of a larger set of integrated studies.Essential long-term studies will be continued and others added to increase spatial andtemporal overlap of scales. The standard 5 LTER core activities will be addressed by work inseven component areas: (1) climate, (2) hydrology, (3) disturbance, (4) ecophysiology,(5) carbon and nutrient dynamics, (6) biodiversity, and (7) stream-forest interactions. In thisgrant cycle, studies continue to examine the interaction of the drivers of change and respondingprocesses and taxa, but the conceptual emphasis will be on temporal behavior, its causes, andits consequences for ecosystem change. We will examine temporal behavior over time scales ofdays to hundreds of years focusing on: (1) modulation, (2) temporal lags, (3) spatial coherence,(4) path dependence, (5) hysteresis, and (6) alternative stable states. Exploring these aspects oftemporal behavior help to address the Central Question by quantifying natural temporalvariability and providing insights into mechanisms that control processes. A major goal will beto test predictive rules (i.e., hypotheses) regulating temporal behaviors. Another focus ofsynthesis will be small watersheds, an important landscape unit providing opportunity forintegration of climatic, ecosystem, and hydrological processes as well as knowledge of temporaland spatial scaling. The ultimate goal in this integration is to create a spatially 3-dimensional(including subsurface and air flow) understanding of the temporal dynamics of the 3 states ofmatter involved in biogeochemical and hydrologic cycles within a watershed. Past experiments,long term records of climate, stream flow, nutrient exports, and vegetation change, as well asmodeling will enhance this integration effort. By understanding this key landscape unit, futurebroader-scale efforts will be strengthened.Andrews science and scientists continue to advance understanding and management offorests and streams of the Pacific Northwest through communication with students, teachers,policy makers, land managers, and the general public. Information management, an essentialactivity for both research and education, emphasizes ease of use, increased accessibility, andportability of many forms of information.