We thought this was a very nice, comprehensive summary of various approaches to estimating parameters relevant to characterization of population growth ( k ). Here, we will focus on several issues which Nichols & Hines (2002) raise. In fact, part of the measure of the signi® cance of this paper is its breadthÐ it nicely reviews several key approaches to estimation of population growth using dat...

By using the upperand lower-solution method of partial functional differential equations and the oscillation theory of functional differential equation, the oscillation of a population equation with diffusion and delay is studied and a sufficient condition for all positive solutions of the equation to oscillate about the positive equilibrium is obtained. Finally, a model arising from ecology is...

There is a widespread opinion among ecologists that ecology lacks general laws. In this paper the author argues that this opinion is mistaken. Taking the case of population dynamics, the author points out that there are several very general law-like propositions that provide the theoretical basis for most population dynamics models that were developed to address specific issues. Some of these f...

Collection

1) Systems Analysis Laboratory, Helsinki University of Technology, P.O. Box 1100, FIN-02015 HUT, Finland 2) Department of Ecology and Systematics, University of Helsinki, P.O. Box 17, FIN-00014 University of Helsinki, Finland 3) Adaptive Dynamics Network, International Institute for Applied Systems Analysis, A-2361 Laxenburg, Austria 4) Department of Biological and Environmental Science, Univer...

Value claims about ecological populations, communities, and systems appear everywhere in literature put out by leading environmental advisory institutions. This essay clarifies the content of such normatively significant value claims in two main steps. In it, I first outline the conception of ecological entities, functionality, and properties, I argue is operative in the background of modern ec...

Mustafa İMREN*, Vahdettin ÇİFTÇİ, Şenol YILDIZ, Halil KÜTÜK, Abdelfattah A. DABABAT Department of Plant Protection, Faculty of Agriculture and Natural Science, Abant İzzet Baysal University, Bolu, Turkey Department of Field Crops, Faculty of Agriculture and Natural Science, Abant İzzet Baysal University, Bolu, Turkey Department of Wildlife Ecology and Management, Faculty of Agriculture and Natu...

Neuhauser et al. (2003) and Whitham et al. (2003) clearly demonstrate the powerful insights that can be gained from examining the evolutionary process in an ecological context by combining community ecology and population genetics. These approaches show how organism interactions can influence rates and direction of evolution, and how genetic variation within populations can influence patterns o...

When satellite data on fire activity first became available for the globe it confirmed perceptions that there is a great deal of burning in Africa. The striking number of active fires recorded in Africa compared with other parts of the world with similar environmental characteristics point to the importance of humans in altering fire regimes on this continent. Humans have been using fire in Afr...