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Comment on "Asymmetric coevolutionary networks facilitate biodiversity maintenance"

Bascompte et al. (Reports, 21 April 2006, p. 431) used network asymmetries to explain mathematical conditions necessary for stability in historic models of mutualism. The Lotka-Volterra equations they used artificially created conditions in which some factor, such as asymmetric interaction strengths, is necessary for community coexistence. We show that a more realistic model incorporating nonlinea
Authors
J. Nathaniel Holland, Toshinori Okuyama, Donald L. DeAngelis

A standard protocol for describing individual-based and agent-based models

Simulation models that describe autonomous individual organisms (individual based models, IBM) or agents (agent-based models, ABM) have become a widely used tool, not only in ecology, but also in many other disciplines dealing with complex systems made up of autonomous entities. However, there is no standard protocol for describing such simulation models, which can make them difficult to understan
Authors
Volker Grimm, Uta Berger, Finn Bastiansen, Sigrunn Eliassen, Vincent Ginot, Jarl Giske, John Goss-Custard, Tamara Grand, Simone K. Heinz, Geir Huse, Andreas Huth, Jane U. Jepsen, Christian Jorgensen, Wolf M. Mooij, Birgit Muller, Guy Pe'er, Cyril Piou, Steven F. Railsback, Andrew M. Robbins, Martha M. Robbins, Eva Rossmanith, Nadja Ruger, Espen Strand, Sami Souissi, Richard A. Stillman, Rune Vabo, Ute Visser, Donald L. DeAngelis

Water-level decline in the Apalachicola River, Florida, from 1954 to 2004, and effects on floodplain habitats

From 1954 to 2004, water levels declined in the nontidal reach of the Apalachicola River, Florida, as a result of long-term changes in stage-discharge relations. Channel widening and deepening, which occurred throughout much of the river, apparently caused the declines. The period of most rapid channel enlargement began in 1954 and occurred primarily as a gradual erosional process over two to thre
Authors
Helen M. Light, Kirk R. Vincent, Melanie R. Darst, Franklin D. Price

Water resources data, Florida, water year 2005. Volume 1A: northeast Florida - Surface water

Water resources data for the 2005 water year in Florida consist of continuous or daily discharge for 429 streams, periodic discharge for 9 streams, continuous or daily stage for 218 streams, periodic stage for 5 streams, peak stage and discharge for 28 streams; continuous or daily elevations for 15 lakes, periodic elevations for 23 lakes; continuous ground-water levels for 401 wells, periodic grou
Authors
A.P. Nazarian, E.P. Simonds, S.M. Dickerson

Drought of 1998-2002: impacts on Florida's hydrology and landscape

Lower than normal precipitation caused a severe statewide drought in Florida from 1998 to 2002. Based on precipitation and streamflow records dating to the early 1900s, the drought was one of the worst ever to affect the State. In terms of severity, this drought was comparable to the drought of 1949-1957 in duration and had record-setting low flows in several basins. The drought was particularly s
Authors
Richard Jay Verdi, Stewart A. Tomlinson, Richard L. Marella

Potentiometric surface of the Upper Floridan aquifer, west-central Florida, May 2005

The Floridan aquifer system consists of the Upper and Lower Floridan aquifers separated by the middle confining unit. The middle confining unit and the Lower Floridan aquifer in west-central Florida generally contain highly mineralized water. The water-bearing units containing freshwater are herein referred to as the Upper Floridan aquifer. The Upper Floridan aquifer is a highly productive aquifer
Authors
A.G. Ortiz, R.A. Blanchard

Regional evaluation of the hydrogeologic framework, hydraulic properties, and chemical characteristics of the intermediate aquifer system underlying southern west-central Florida

Three major aquifer systems-the surficial aquifer system, the intermediate aquifer system, and the Floridan aquifer system-are recognized in the approximately 5,100-square-mile southern west-central Florida study area. The principal source of freshwater for all uses is ground water supplied from the three aquifer systems. Ground water from the intermediate aquifer system is considered only moderat
Authors
Lari A. Knochenmus

Characterization of the hydrology, water chemistry, and aquatic communities of selected springs in the St. Johns River Water Management District, Florida, 2004

The hydrology, water chemistry, and aquatic communities of Silver Springs, De Leon Spring, Gemini Springs, and Green Spring in the St. Johns River Water Management District, Florida, were studied in 2004 to provide a better understanding of each spring and to compile data of potential use in future water-management decisions. Ground water that discharges from these and other north-central Florida
Authors
G. G. Phelps, Stephen J. Walsh, Robert M. Gerwig, William B. Tate

Potentiometric surface of the Upper Floridan aquifer, west-central Florida, September 2005

The Floridan aquifer system consists of the Upper and Lower Floridan aquifers separated by the middle confining unit. The middle confining unit and the Lower Floridan aquifer in west-central Florida generally contain highly mineralized water. The water-bearing units containing freshwater are herein referred to as the Upper Floridan aquifer. The Upper Floridan aquifer is the principal source of wat
Authors
A.G. Ortiz

Host mating system and the prevalence of a disease in a plant population

A modified susceptible–infected–recovered (SIR) host–pathogen model is used to determine the influence of plant mating system on the outcome of a host–pathogen interaction. Unlike previous models describing how interactions between mating system and pathogen infection affect individual fitness, this model considers the potential consequences of varying mating systems on the prevalence of resistanc
Authors
Jennifer M. Koslow, Donald L. DeAngelis

Potentiometric surface of the Upper Floridan aquifer in the Ichetucknee springshed and vicinity, northern Florida, September 2003

The Upper Floridan aquifer is a highly permeable unit of carbonate rock extending beneath most of Florida and parts of southern Alabama, Georgia, and South Carolina. The high permeability is due in a large part to the widening of fractures that developed over time and the formation of conduits within the aquifer through dissolution of the limestone. This process has also produced numerous karst fe
Authors
A. Alejandro Sepulveda, Brian G. Katz, Gary L. Mahon