Global Lake Ecological Observatory Network (GLEON)

The Global Lake Ecological Observatory Network (GLEON) is a grassroots network of limnologists, information technology experts, and engineers who have a common goal of building a scalable, persistent network of lake ecology observatories. Data from these observatories will allow us to better understand key processes such as the effects of climate and landuse change on lake function, the role of episodic events such as typhoons in resetting lake dynamics, and carbon cycling within lakes. The observatories will consist of instrumented platforms on lakes around the world capable of sensing key limnological variables and moving the data in near-real time to web-accessible databases. A common web portal will allow easy access to researchers and the public. A series of web services supported by this portal will allow computation of metrics based on the high frequency data. Such metrics would include estimates of rates of important processes such as gross primary production and respiration.

Historical Precursors to GLEON: Collaborative Lake Metabolism Project

Understanding the factors influencing the carbon balance of lakes is a longstanding goal in aquatic ecology (Cole et al. 1994, Kling et al. 1991) because the carbon balance reflects both a lake’s biological activity and its links with its landscape and climatic settings. Scientists at the North Temperate Lakes Long-Term Ecological Research site have contributed uniquely to lake metabolism research, in part through ecosystem-scale measurements of important fluxes of carbon to and from lakes (Riera et al. 1999, Hope et al., 1996, Kratz et al. 1997) and biological processes influencing in-lake processing of carbon (Hanson et al. 2003). Here, we request supplemental funding to enable collaboration with colleagues in Taiwan for the purpose of studying the metabolism of Yuan Yang Lake, a sub-tropical lake that is part of the Taiwan Long-Term Ecological Research network. Through automated sampling of Yuan Yang Lake and data transmission over the Internet, we propose to compare its metabolism with lakes at the North Temperate Lakes LTER site.


North Temperate Lakes: Long Term Ecological Research Network (NTL-LTER)

The long-term regional ecology of North Temperate lakes is the theme for the North Temperate Lakes LTER. Our vision is to gain a predictive understanding of the ecology of lakes at longer and broader scales than has been traditional in limnology. Thus, we analyze and interpret data we collect over long periods on suites of lakes. The lakes are located from high to low in the landscapes of forested, agricultural, and urban catchments. We also collaborate with other long-term lake sites in the Laurentian Great Lakes region and elsewhere. Our research program is interdisciplinary and aims to understand the ecology of lakes in relation to relevant atmospheric, geochemical, landscape and human processes. Our overarching research question is: How do biophysical setting, climate, and changing land use and cover interact to shape lake characteristics and dynamics over time (past, present, future)? We address this question through five inter-related goals:

* perceive long-term changes in the physical, chemical, and biological properties of lakes these lake ecosystems
* understand the drivers of temporal variability in lakes and lake districts
* understand the interaction of spatial processes with long-term change
* understand causes and predictability of rapid, extensive change in ecosystems
* build a capacity to forecast the future ecology of lake districts

Our two field stations facilitate research in the lake districts – the Hasler Laboratory of Limnology on Lake Mendota in the Yahara Lake District of southern Wisconsin and the Trout Lake Station in the Northern Highlands of Wisconsin. Most of our data are public and available through this web site. Most of our long-term data sets date to 1981 when this site became one of the first 6 LTER sites funded by the U.S. National Science Foundation, but several originate as early as the 1850s or as late as the mid 1990s. We invite collaboration with others.


North Temperate Lakes Microbial Observatory (NTL-MO)

The overarching goal of the North Temperate Lakes Microbial Observatory (NTL-MO) is to identify and describe drivers that shape the structure and dynamics of microbial communities. We are closely linked with the NTL-LTER and study many of the same lakes. During our most recent funding cycle, we are focused on darkly stained humic lakes in the Northern Highlands of Wisconsin. However, we also have active projects in southern Wisconsin, including in Lake Mendota. Our three specific aims are:

* Aim 1: Determine which biological interactions are most important in structuring community dynamics within a lake
* Aim 2: Evaluate how disturbance influences community structure and dynamics at local and regional scales
* Aim 3: Identify the effects of natural selection on population and community structure

In the Yahara Lake District of southern Wisconsin, we are currently studying (1) how phytoplankton interact with bacterial communities to shape their seasonal dynamics; (2) the effect of water column thermal structure on bacterial communities, with a focus on cyanobacteria; and (3) the population structure of cosmopolitan Actinobacteria and potentially toxic cyanobacteria.