Konza Prairie LTER Program

The National Science Foundation's Long Term Ecological Research (LTER) Program began funding research in 1981 after a series of workshops and planning meetings in the late 1970's (Callahan 1984). The value of, and need for, long-term ecological studies had been recognized for many years by ecologists (Likens 1983; Franklin 1989). Rationale for development of the LTER program included explicit recognition of the low rate of change of many significant ecological processes, the importance and prevalence in most ecosystems of rare events and episodic phenomena with long return intervals, the tremendous interannual variability of many ecological processes, and the value of long-term databases for providing the context for shorter term studies. The LTER program was designed to support a multidisciplinary approach to addressing long-term questions in a wide variety of biomes in North America and beyond. Both site-based and coordinated research among the network of LTER sites (numbering 24 in 2002) are enhancing our understanding of ecological phenomena and processes operating over broad spatial scales, as well as long-time scales (Hobbie et al. 2003).

LTER Core Areas

All LTER sites conduct research in 5 general "core" areas established at the start of the LTER program (Callahan 1984). These core areas focus on understanding and documenting (1) patterns and controls of primary production, (2) spatial and temporal dynamics of key populations, (3) patterns and controls of organic matter accumulation in surface layers and sediments, (4) patterns of inorganic input and movements through soils, groundwater, and surface water, and (5) patterns and frequency of disturbances to the system. Within the broad areas, sites are free to focus on the biota processes most relevant to their specific site. For example, LTER research at Konza Prairie focuses on fire, grazing and climatic variability as essential, interactive drivers of ecological processes in mesic grassland ecosystems.

History of the Konza Prairie LTER Program

Konza Prairie was one of 6 original LTER sites selected by NSF in 1981 and is now in its fifth funding cycle (LTER V: 2002-2008). With each successive funding cycle, LTER research goals at Konza Prairie have been redirected and expanded, but the emphasis on fire, grazing and climate together with long-term studies in each of the 5 core areas have been, and continue to be, a baseline research effort that receives high priority.

LTER I (1981-1986).  A group of KSU faculty led by G. Richard Marzolf in collaboration with Dean Bark, Lloyd C. Hulbert, Mike Johnson, Robert Robel and John L. Zimmerman was responsible for securing funding for LTER I, and focusing the initial research program on comparative investigations of biotic responses to fire and climatic variability. Long-term research sites and sampling protocols were established during this period with an emphasis on studies of the extremes of annually burned vs. unburned watersheds and upland vs. lowland sites. Many of these research sites and datasets, established at the onset of the Konza LTER program, have continued as core components of our LTER program.

LTER II (1986-1990).  During LTER II, Marzolf left KSU and Donald Kaufman and Timothy Seastedt expanded our LTER research efforts to include a wider range of fire frequencies (specifically 4-yr fire cycles) and increased exploration of ecosystem responses. An increased emphasis was placed on soil processes, and new plot-level experiments (e.g., the Belowground Plot Experiment) were initiated. Moreover, as a result of the collaborative NASA funded FIFE (First ISLSCP Field Experiment) program from 1987-1989, LTER researchers began to address more complex questions of scale and make use of remotely-sensed satellite data to explore landscape-level issues.

LTER III (1991-1996).  Prior to leaving KSU in 1991, Seastedt provided leadership in defining the research objectives for LTER III.  Leadership and administration during LTER III were provided by Alan Knapp and John Briggs, with co-PIs David Hartnett and Don Kaufman serving in advisory roles.  LTER III represented a significant expansion of the Konza Prairie LTER program in terms of both research emphasis and scientific investigators.  New faculty scientists added during LTER III included Walter Dodds (1991, Aquatic Ecology), John Blair (1992, Soil and Ecosystem Ecology), and Loretta Johnson (1995, Plant and Ecosystem Ecology).  The primary goals of LTER III were to understand how grazing influences biotic and ecosystem processes and patterns imposed by fire frequency over the landscape mosaic, all of which are subjected to a variable (and possibly directional) climatic regime. The additional research associated with large ungulate grazing and an expanded landscape perspective led to the establishment of several challenging studies, many of which are ongoing. These new initiatives were designed to complement programs at other LTER sites as well as enhance efforts within the LTER core areas.

LTER IV (1996-2002).  Leadership during LTER IV was provided by Alan Knapp, John Blair and John Briggs, with co-PIs Hartnett, Kaufman, Dodds and Johnson. Briggs left KSU in 1998, but has remained an active researcher and Co-PI. During LTER IV, we built on existing long-term studies of fire, grazing and climatic variability with a broadly-based research program encompassing studies from the organismic through population, community, and ecosystem levels.  LTER research was expanded to include studies of climate change, net carbon exchange, restoration ecology and land use/land cover change. These studies were linked via an overarching theme that addresses the major abiotic and biotic factors influencing this ecosystem and explicitly includes a non-equilibrium perspective on ecological patterns and processes in this grassland (Knapp et al. 1998). New KSU faculty scientists added during LTER IV included Ari Jumpponen (1999, Fungal Ecology), Karen Garrett (1999, Plant Disease Ecology), Kimberly With (2000, Landscape Ecology), Brett Sandercock (2000, Avian Ecology), Carolyn Ferguson (2001, Plant Systematics), Keith Gido (2001, Aquatic Ecology).

LTER V (2002-2008). LTER V is being led by Blair, with Knapp, Briggs, Hartnett and Johnson, Dodds and Kaufman as Co-PIs. Although Knapp left KSU in 2003, he remains an active participant and Co-PI. The goals of the Konza LTER V program are three-fold:

1.      to continue and expand the strong core LTER experiments on fire, grazing and climatic variability begun over 20 years ago, with the goal of improving our understanding of the major abiotic and biotic factors determining grassland structure and function;

2.      to further develop a mechanistic and predictive understanding of grassland dynamics and responses to multiple global change phenomena, using ongoing and new long-term experiments and datasets, coupled with shorter-term supporting studies;

3.      to expand our synthesis activities based on LTER results, and use these syntheses to develop and test current ecological theory.

Our experiments incorporate these goals and explicitly consider the major drivers of ecological dynamics in these grasslands, and their interactions with global change phenomena at local and regional scales. A major new emphasis is global change and the responses of grassland ecosystems. We define global change broadly as human-induced alterations in climate, land-use, hydrologic and biogeochemical cycles, and species introductions. We focus on aspects of global change most relevant to grasslands: changes in land use (especially fire and grazing regimes) and land cover (increases in woody cover); climate change; altered nutrient cycles (enhanced N deposition); and biological invasions. During LTER V, we will: 1) continue core long-term experiments focused on land-use (fire and grazing) and climatic variability (natural and manipulated); 2) expand climate change studies initiated during LTER IV (precipitation and temperature regimes); 3) initiate new experiments on the consequences of altered hydrologic regimes for stream ecosystems, 4) initiate and continue long-term studies of nutrient enrichment and interactions with land-use practices; 5) conduct new experiments on invasibility in grasslands, and 6) assess the causes and consequences of land-cover change, incorporating sociological and ecological perspectives. New KSU faculty scientists include Tony Joern (Insect Ecology, 2003) and Samantha Wisely (2003, Wildlife Ecology), along with an increased number of investigators from other institutions.

References.
Callahan, J. T.  1984.  Long-term ecological research.  BioScience 34:363-367.
Franklin, J. F.  1989.  Importance and justification of long-term studies in ecology.  Pages 3-19 in G. E. Likens, editor.  Long-Term Studies in Ecology.  Springer-Verlag, New York, New York, USA.
Hobbie, J. E., S. R. Carpenter, N. B. Grimm, J. R. Gosz and T. R. Seastedt. 2003. The US Long Term Ecological Research Program. BioScience 53:21-32.
Knapp, A. K.,  J. M. Briggs, D. C. Hartnett and S. C. Collins (eds.).  1998.  Grassland Dynamics: Long-Term Ecological Research in Tallgrass Prairie, Oxford University Press, New York, USA.
Krebs, C. J.  1991. The experimental paradigm and long-term population studies.  Ibis 133 (Supplement 1):3-8.
Likens, G. E.  1983.  A priority for ecological research.  Bulletin of the Ecological Society of America 64:234-243.