Peter Wyckoff

Biology Department Guilford College 5800 West Friendly Ave. Greensboro North Carolina 27410 USA

(336) 316-2421 pwyckoff@guilford.edu http://coweeta.ecology.uga.edu James Clark

Department of Botany Duke University Durham North Carolina 27708 USA

(919) 660-7402 jimclark@duke.edu http://cwt33.ecology.uga.edu/piprofiles/pro_clark.html From an article from this study In Press at the Canadian Journal of Forest Research Ecologists and foresters have long noted a link between tree growth rate and mortality, and recent work suggests that interspecific differences in low growth tolerance is a key force shaping forest structure. Little information is available, however, on the growth-mortality relationship for most species. We present three methods for estimating growth-mortality functions from readily obtainable field data. All use annual mortality rates and the recent growth rates of living and dead individuals. Annual mortality rates are estimated using both survival analysis and a Bayesian approach. Growth rates are obtained from increment cores. Growth-mortality functions are fitted using two parametric approaches and a non-parametric approach. The three methods are compared using bootstrapped confidence intervals and likelihood ratio tests. For two example species, Acer rubrum and Cornus florida, growth-mortality functions indicate a substantial difference in the two species abilities to withstand slow growth. Both survival analysis and Bayesian estimates of mortality rates lead to similar growth-mortality functions, with the Bayesian approach providing a means to overcome the absence of long-term census data. In fitting growth-mortality functions, the non-parametric approach reveals that inflexibility in parametric methods can lead to errors in estimating mortality risk at low growth. We thus suggest that non-parametric fits be used as a tool for assessing parametric models. Living and recently dead trees from a variety of trees were cored. Ring widths were measured with a Windendro Measuring System. Coweeta LTER tree rings tree mortality Must adhere to the Coweeta LTER Data Policy (See http://coweeta.ecology.uga.edu/webdocs/3/static/datapolicies.html). http://cwt33.ecology.uga.edu/summaries/summary1004.html Watershed 18, near plot 218; Watershed 27, near plots 427 and 527 2000-01-01 1995-06-01 Coweeta LTER Information Manager

Institute of Ecology University of Georgia Athens Georgia 30602 USA

(828) 524-2128 Ted Gragson

Institute of Ecology University of Georgia Athens Georgia 30602 USA

tgragson@earthlink.net principalInvestigator James Vose

Institute of Ecology University of Georgia Athens Georgia 30602 USA

jvose@fs.fed.us principalInvestigator Brian Kloeppel

Institute of Ecology University of Georgia Athens Georgia 30602 USA

kloeppel@sparc.ecology.uga.edu principalInvestigator The Coweeta LTER Research Program has evolved since 1980 from a site-based to a site- and region-based project examining the effects of disturbance and environmental gradients on biogeochemical cycling, and the underlying watershed ecosystem processes that regulate and respond to those cycles. The objective for the 2002-2008 research is to advance scientific understanding of the spatial, temporal, and decision-making components of land use and land-use change in the southern Appalachian Mountains over the last 200 years, and forecast patterns into the future 30 years. This will be accomplished by addressing ecological and socioeconomic aspects of land-use change while continuing long-term studies of environmental gradients and natural disturbance regimes. The result will be a more complete understanding of ecological dynamics in the southern Appalachian Mountains that makes possible the development of reasonable forecasts of its future ecological state. | The guiding hypothesis for the proposed research is that the frequency, intensity, and extent of land use represents human decision-making in response to socioeconomic and bio-geophysical conditions with consequences that cascade through ecosystems. The research activities are organized into three initiatives: (1) Characterization of the Socio-Natural Template, (2) Ecosystem Responses to the Socio-Natural Template, and (3) Forecasting Ecosystem Responses to Changes in the Socio-Natural Template. The integrated scientific research will provide both a description as well as an explanation of the underlying causes of land use and the consequences of land-use change for southern Appalachian ecosystems and society. It thus recognizes the complexity of land use as a process and the research needs as defined in the LTER Program and the broader scientific community. National Science Foundation. Any opinions, findings, conclusions, or recommendations expressed in the material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. uid=cwt,o=lter,dc=ecoinformatics,dc=org all public read 1004.csv 1004.csv 1 \n \n column , http://cwt33.ecology.uga.edu/data/1004.csv Species Species First two letters of Genus and Species name. First two letters of Genus and Species name. none Missing Value Diameter Diameter Diameter of breast height of sample tree centimeter real none Missing Value Status Status Living status of the tree 0 recently dead 1 living trees none Missing Value Site Site site code 1 area near gradiant plot 218 2 area near plot 427 3 area nearplot 527 none Missing Value Last10 Last10 average radial growth in mm for the 10 most recent growth years millimeter real none Missing Value Last5 Last5 average radial growth in mm for the 5 most recent growth years millimiter real none Missing Value Last4 Last4 average radial growth in mm for the 4 most recent growth years millimeter real none Missing Value Last3 Last3 average radial growth in mm for the 3 most recent growth years millimeter real none Missing Value Last2 Last2 average radial growth in mm for the 2 most recent growth years millimeter real none Missing Value Last1 Last1 average radial growth in mm for the 1 most recent growth years millimeter real none Missing Value