The Role of Sites in Global Change Research

Network News Spring 1990, Vol. 7 No. 1
Site News

Last November representatives from 24 major ecosystem programs met to analyze the potential contribution of an intensive site network to research global change. There were several unusual aspects to the workshop. Most of the programs had prepared extensive analyses of their current capabilities and interests that were provided to all participants. Also unique was the mixture of programs that participated, including sites supported by the National Science Foundation, the U.S. Department of Energy (three National Laboratories), the National Park Service, the Smithsonian Institution, the National Oceanic and Atmospheric Administration, and the U.S. Forest Service, among other agencies and organizations.

It is rare, indeed, when any significant group of ecologists is able to reach consensus on the elements and priorities of a major research program. Therefore, it was a notable accomplishment that participants at this workshop not only identified key research areas in global change where a site network could make a major contribution, but also agreed upon a list of 12 top priority activities, or action items.

The 12 action items included: major multi-site “flagship” syntheses and modeling activities, the implementation of long-term measurement programs, and the development of specialized technical capabilities. A publication summarizing the results of the workshop and highlighting the action items is in preparation at the Network Office, and is already being shared with the agencies and committees involved in planning and implementing global change research programs. Here is a peek at the proposed program.

Experimental studies proposed include one on the effects of CO2 enrichment on ecosystem processes and another on effects of soil warming.

Enclosed ecosystems might be required to determine the effects of heightened CO2 levels on primary productivity and water-use efficiency, as well as other community variables.

Installations would, by the difficulty and expense of providing the control, necessarily be limited to a few sites representative of a cross-section of ecosystem types.

The soil warming experiment, on the other hand, could be conducted across many sites--at least in its simplest form. The objective here is to develop definitive data on the ecological effects of increased soil temperatures (and altered moisture regimes) on carbon storage, productivity, trace gas fluxes, and soil biota. This research is viewed as very high priority because of the large pools of carbon associated with soils and detritus and our poor understanding of their dynamics.

The synthesis and modeling activities proposed include:

  1. Megalandscape experiments --designing very large-scale experiments to address critical issues in the conservation of biological diversity, such as landscape connectivity and the effects of patch size and context;
  2. Hydrologic models -- collaborative development of a general model (or family of models) applicable across biome types which incorporates soil, surface, and ground water components in a geographic information systems context;
  3. Disturbance regimes -- analyses of the effects of global change on disturbance regimes and consequent changes in productivity, carbon storage, trace gas emissions, and biological diversity of ecosystems, landscapes and regions; and
  4. Ecological scaling -- an accelerated program to develop and demonstrate approaches to the problem of scaling up scientific information from processes and sites to landscapes and regions.

The development of regional predictions of precipitation and disturbance regimes is critical for the assessment of ecological impacts. Workshop participants agreed that disturbances, such as wildfire, tropical storms, drought, will drive much ecological change under global climate change which will, in turn, feed back into the environment. Ecologists must persuade atmospheric scientists to give this work higher priority, and to collaborate in all phases of the research.

The development of technical capabilities is an important component of the proposed program. Systems are recommended for improved access to forest canopies, a major habitat for organisms and the major interface between the ecosystem and the atmosphere where critical physiological and physical processes occur. An adaptation of current building construction crane technology (see page 12) may provide badly needed safe, dependable access to extensive volumes of forest canopy (and the space above it).

Mobile field laboratories are another tool’ needed for global change research, to take full advantage of the opportunities to learn about ecosystem processes provided by natural catastrophic events, Many critical responses take place in days or weeks following an event, before scientists can mobilize. Also, much global change research will require collective analytical abilities. Mobile laboratories and associated scientific rapid-response or “ECOSWAT” learns, quickly transported by ground or air, could service major experiments and sites when not assisting local scientific teams in responding to catastrophic events.

These, then, are some of the action items identified in the global change workshop. Participants can take pride in having worked so well together to identify the research potential of site-based programs and, especially, to agree on specific, high- priority research tasks. Such consensus is absolutely essential if biologists and ecologists are to significantly influence the overall global climate change research program.