Abstract Ecological status classification systems based on biological elements (e.g., macroinvertebrate communities) are dependent their response to different pressures. However, there is a need determine if invasive species should be incorporated indicator parameters (i.e. metrics measurements of richness and diversity) or as pressure affecting such parameters. Moreover, because ecosystem lack...

Ecological and biological processes can change from one state to another once a threshold has been crossed in space or time. Threshold responses to incremental changes in underlying variables can characterize diverse processes from climate change to the desertification of arid lands from overgrazing. Simultaneously estimating the location of thresholds and associated ecological parameters can b...

Background Determinants of health or health production function in health economics literature constitute noticeable issues in health promotion. This study aimed at estimating a health production function for East Mediterranean Region (EMR) based on the Grossman theoretical model.   Methods This ecological study was performed using the econometric methods. The panel data model was used in order...

Global bifurcation analysis of a class of general predator-prey models with a strong Allee effect in prey population is given in details. We show the existence of a point-to-point heteroclinic orbit loop, consider the Hopf bifurcation, and prove the existence/uniqueness and the nonexistence of limit cycle for appropriate range of parameters. For a unique parameter value, a threshold curve separ...

Evolutionary ecological frameworks can give us new insights into the emergence of human adaptations such as language and cultural learning. There now exist several well-speciŽed models of the social and ecological conditions in which the human capacity for language came under strong positive selection pressure. We critically review them, and ask how we can test them using archaeological evidenc...

Introduction: The brown planthopper (BPH), Nilaparvata lugens (Stål) (Hemiptera: Delphacidae), is a notorious insect pest of rice. Nutrient supplementation can alter plant biochemical compositions which may indirectly affect on ecological fitness parameters of its insect pest. However, few findings are available on nutrient-induced ecological fitness of BPH and relationship of BPH fitness param...

Previous papers have modelled the behaviour of populations which are subject to kleptoparasitism, and found those ecological situations in which kleptoparasitism should occur. Individuals were considered to be in one of several states, and an equilibrium distribution for the population was found. It was then assumed, for analytical purposes but without proof, that the population was actually in...

Ecologists collect and evaluate data from all possible data sources, sources of objective (mostly quantitative) data, like measurements and simulation results and sources of subjective (often only imprecise qualitative) information, like subjective estimations obtained from an expert. Not all ecological parameters are measurable, for example, the number and biomass of fi sh in a particular lake...