No increase in fluctuating asymmetry in ground beetles (Carabidae) as urbanisation progresses

Environmental stress can lead to a reduction in developmental homeostasis, which could be reflected in increased variability of morphological traits. Fluctuating asymmetry (FA) is one possible manifestation of such a stress, and is often taken as a proxy for individual fitness. To test the usefulness of FA in morphological traits as an indicator of environmental quality, we studied the effect of urbanisation on FA in ground beetles (Carabidae) near a Danish city. First, we performed a critical examina- tion whether morphological character traits suggested in the literature displayed true fluctuating asymmetry in three common predatory ground beetles, Carabus nemoralis, Nebria brevicollis and Pterostichus melanarius. Eight metrical (length of the second and third antennal segments, elytral length, length of the first tarsus segment, length of the first and second tibiae, length of the proximal and distal spines on the first femurs) and one meristic (the number of spines on the second tibiae) traits were examined. Most of them showed FA but not consistently. Females generally displayed a higher level of FA than males. Finally, we examined the changes in the level of FA in bilateral morphological traits along an urbanisation gradient (forest - suburban forest - forest fragments in urban park) to test whether environmental stress created by urbanisation is reflected in FA. Ground beetles common along a Danish urbanisation gradient did not seem to indicate differences in habitat quality by their level of F

Developing an integrated land use planning system on reclaimed wetlands of the Hungarian Plain using economic valuation of ecosystem services

The establishment of a sustainable land use system is crucial in Hungary (SE Europe) where 30% of croplands lie on former floodplains, and 40–45% of arable lands are drought-prone. We calculated and compared the monetary value of the main wetland ecosystem services, the profitability of land use and the additional costs of grain producer system on land at risk from groundwater inundation on the Hungarian Plain. We show that orchards and forestry generate a much higher profitability in former wetlands than cropland farming. Using the replacement cost method, we prove that the reservoir capacity of restored wetlands with an ecologically optimal 0.5 m water depth could replace 2150 €ha−1 flood protection investment cost. The calculated costs of protecting land under the two highest groundwater risk categories between 1999–2005 was 37.2 €ha−1 y−1 and 14.9 €ha−1 y−1, respectively. Although the flood protection benefits of former wetlands may provide an appropriate value base for restoration per se, combined with the potential advantages of land use change from cropland to forest in former wetlands and the carbon sequestration benefit provide ‘win-win’ solutions for land users and institutional actors interested in flood prevention, environmental protection and climate mitigation

Variation for carbon isotope ratio in a set of emmer (Triticum dicoccum Schrank) and bread wheat (Triticum aestivum L.) accessions

A high level of drought tolerance is an important objective in breeding new generation wheat varieties. A group of six landraces of the emmer wheat (Triticum diccocum Schrank), as well as two landraces, two old cultivars and two modern varieties of bread wheat (Triticum aestivum L.) were evaluated for their ability to discriminate 13C, a trait related to stomatal closure and consequently, an important component tolerance to drought. Three emmer wheat landraces and one of the bread wheat landraces has the lowest. Therefore, emmer wheat may play the role of a donor of the tolerance to drought in wheat breeding programs targetting drought prone conditions.Key words: Emmer wheat, bread wheat, drought tolerance, carbon isotope ratio, discrimination

Circadian pattern and burstiness in mobile phone communication

The temporal communication patterns of human individuals are known to be inhomogeneous or bursty, which is reflected as the heavy tail behavior in the inter-event time distribution. As the cause of such bursty behavior two main mechanisms have been suggested: a) Inhomogeneities due to the circadian and weekly activity patterns and b) inhomogeneities rooted in human task execution behavior. Here we investigate the roles of these mechanisms by developing and then applying systematic de-seasoning methods to remove the circadian and weekly patterns from the time-series of mobile phone communication events of individuals. We find that the heavy tails in the inter-event time distributions remain robustly with respect to this procedure, which clearly indicates that the human task execution based mechanism is a possible cause for the remaining burstiness in temporal mobile phone communication patterns.Comment: 17 pages, 12 figure

Liapunov Functions for Neural Network Models

The dynamical behaviour of continuous time recurrent neural network models is studied with emphasis on global stability of a unique equilibrium. First we show in a unified context two Liapunov functions that were introduced in the nineties by Hopfield, Grossberg, Matsouka and Forti. Then we introduce a class of networks for which the model becomes a special cooperative system with a unique globally stable steady state. Finally, we show that periodic orbits may occur when the sufficient conditions for the existence of Liapunov functions are violated