I was born a biologist. There was never any decision; it was just what I was. I always wanted to know everything about everything in nature, and in the world around me. And I was fortunate to find others—teachers, acquaintances, and eventually mentors—who appreciated my enthusiasm and shared their time with me.

But biology is a big field and "everything about everything" is a big task. And so I did many things. In high school I participated in a cooperative program that allowed me to work half time in the plant laboratory of a biomedical research firm. There I learned the scientific method, and I wonder if I ever really would have or could have learned that in a class. I worked in labs, too, as an undergraduate, with friendly, supportive scientists, and even did some independent research. I changed majors several times before settling in botany, but it was ecology that really enthralled me. Finally, a field about how everything influences everything! How great is that?! And then, at University of Florida, I met Dr. H.T. Odum and he, more than anyone, taught me how to think in a brand new way.

  What, in your opinion, is the significance of your work for the field?

By approaching questions from the system level, I have attempted to provide constraints—total limits within which all the individual pieces must fit. The soil is a fine example: measurements of soil respiration provide a constraint on total carbon dioxide production by all organisms in the soil, including bacteria, fungi, invertebrates, and plant roots. Each of these individual fluxes is difficult to measure, but measurement of the whole-system flux provides a quantitative constraint that is invaluable for interpreting and integrating the information derived from other studies. It allows us to better understand not just organisms or processes or materials, but how they interact with one another and function together. This view is not unique, nor my own, but is neither generally taught nor widely understood. By clearly describing and meaningfully applying the ecosystems approach, I hope to provide both useful insights into questions, and a methodology that will assist others.

  What were the greatest challenges in performing and presenting your work?

There is a widespread lack of understanding of whole-system approaches to ecology, among biologists at large, and overcoming the resulting distrust, disbelief, disregard, and criticism of otherwise intelligent scientists is sometimes challenging. But this paper was fun to write, and provided an excellent opportunity to collaborate closely with a scientist that I respect very much.

  What is your prediction for the state of our knowledge about your field 10 years from now?

This paper was in many respects an update of Schlesinger (Ann. Rev. Ecol. Syst. 8:51-81, 1977) and in several ways highlighted similar patterns, thus verifying their validity. It did more, as well, and 10 years hence we will have the ability, because of improved techniques and due to more widespread and temporally extended measurements, to evaluate the belowground carbon cycle in a much more meaningful way. Very much needed, but sure to arise, is a better ability to quantify and predict the effects of soil moisture status on soil biological activity in all types of soils. We will certainly be able to better disentangle the multiple sources of carbon dioxide in soils, and thus to better evaluate the effects of human impacts on individual belowground processes, but we still have a long way to go. With all this will come a better understanding of the physical and biological processes that govern the terrestrial carbon cycle, which we actually know quite poorly. This understanding is essential if we are to meet societal demands that we look into the future, and describe in a robust way what the probable impacts of our various activities are.

  Which of your professional achievements brings you the most satisfaction?

I have been very lucky to have had many opportunities to go someplace new and work with new collaborators, and I have enjoyed most the many opportunities I have had to work with truly wonderful people who are also excellent scientists. Publishing papers that are read and used by others is also very gratifying, and publishing a highly cited paper is exceptionally so. But seeing that eye-sparkle of understanding that suddenly comes during one-on-one discussions; that is really tops.

  What lessons would you draw from your work to pass on to the next generation of researchers?