Dr. Enquist is a broadly trained plant ecologist. His lab investigates how functional and physical constraints at the level of the individual (anatomical and physiological) influence larger scale ecological and evolutionary patterns. In particular, the lab focuses on two core areas:

1. (1)Highlighting and deducing general principles, scaling rules, and the physical constraints influencing the evolution of organismal form, function, and diversity;
   

2. (2)Understanding the larger scale ramifications (ecological, evolutionary, and ecosystem) of these rules/constraint
   

In order to address these critical issues the lab uses both theoretical, computational, informatics, biophysical and physiological and ecophysiological approaches.

Research in the lab can be summarized into four distinct yet

interrelated areas:

(i) Functional diversity and the evolution of form;

2. (ii)The origin of allometric relationships (how characteristics of organisms change with their size), phenotypic integration, and the scaling of biological processes from cells to ecosystems.
   

(iii) The evolution of life-history and allocation strategies;

(iv) Community ecology and macroecology.

Field Site Overview

Dr. Enquist's research interests also include observations and insight obtained from the monitoring of long-term dynamics of growth and change within a tropical forest in the Area de Conservacion, Guanacaste, Costa Rica. Several additional sites in Latin America as well as a field project at the Rocky Mountain Biological lab in Colorado.  See below for more information on the Guanacaste and RMBL project.

Local Field Opportunities . . . In addition, lab research has also focused on several new field projects in the Southwest related to the above areas of focus. Here are three movies to show some local field sites where we have worked . . .

Click Here to see a short movie taken from the top of Tumamoc Hill - our close by research site associated with the Desert Lab.  You can see Tucson and the many surrounding mountains

Click Here to see a short movie from the Santa Rita Experimental range - a 20 minute drive south of Tucson.

Click Here to see a short movie from half way up Mt. Lemmon - 30 minute drive northeast of Tucson. We are currently studying plant physiological traits along an elevational gradient on Mt. Lemmon. This movie was shot during the 2002 ESA meeting field trip along the Whittaker and Niering transect up Mt. Lemmon (hence all the people).

Long-term Dynamics and Structure of a Tropical Forest

Most of Dr. Enquist's empirical research in based on the long-term dynamics of a ~20ha permanent plot located in the lowland tropical-dry-forests of Guanacaste, Costa Rica. The research site is located within the Area de Conservacion Guanacaste , specifically Santa Rosa National Park. This plot was originally surveyed 20 years ago by S.P. Hubbell and G.C.Stevens.

Recently, in collaboration with Carolyn A. F. Enquist the forest was resurveyed - containing approximate 50,000 individual trees consisting of ~200 woody species within the plot. Research in the 'San Emilio' forest focuses on tree population dynamics, the influence of soil and soil moisture and local and regional climatic changes on local dynamics. Also, in collaboration with Josh Leffler the use of stable isotopes and tree rings to more closely match physiological attributes with local and regional distribution.

More information on the Santa Rosa San Emilio long-term monitoring plot will be coming shortly . . .

For a copy of my vegetative key to the trees and woody shrubs of Upland Deciduous Forest of the ACG click here . This work, in collaboration with Jon Sullivan, is also published online via the ACG. The URL is available on the Flowering Plants Species Webpages URL listed below.

Visit the Flowering Plant Species Homepages for Guanacaste Costa Rica by clicking here En Espanol

Help grow the Guanacaste Conservation Area - purchase threatened rainforest here .

Assessing community functional composition and ecosystem flux across elevational gradients - RMBL

Scaling the functional attributes of plants, communities, and ecosystems across elevational gradients: Responses to climate change - Rocky Mountain Biological Lab

An important question in ecology is to understand how attributes of species influence the functioning of ecosystems. This study is designed to forge links between variation in the physical environment (e.g., changes in temperature and precipitation with elevation), changes in the functional attributes of plant species (plant size, leaf morphology and physiology etc.) and the functioning of whole ecosystems (the fluxes of carbon and water).

Synthesizing this knowledge is critical for predicting responses of the biosphere to climate change. The mountainous landscape in and around RMBL provides enormous range of physical conditions, from warm wet meadows to cold dry ridge tops. The resulting plant communities are likewise both functionally and phylogenetically diverse. We propose to assess how plant functional diversity and whole ecosystem fluxes vary across a range of elevations and environments. Our work at RMBL will be part of a larger global project. We are in the process of starting similar elevational studies of plant functional diversity and ecosystem fluxes across elevational gradients in SE Arizona and Costa Rica. Data from these field studies will form the basis for the development and testing of mechanistic, predictive models linking the functional attributes of organisms to large scale processes in plant communities and ecosystems.