Analysis of landrace cultivation in Europe: A means to support in situ conservation of crop diversity

During the last century, the progressive substitution of landraces with modern, high yielding varieties, led to a dramatic reduction of in situ conserved crop diversity in Europe. Nowadays there is limited and scattered information on where landraces are cultivated. To fill this gap and lay the groundwork for a regional landrace in situ conservation strategy, information on more than 19,335 geo-referenced landrace cultivation sites were collated from 14 European countries. According to collected data, landraces of 141 herbaceous and 48 tree species are cultivated across Europe: Italy (107 species), Greece (93), Portugal (45) and Spain (44) hold the highest numbers. Common bean, onion, tomato, potato and apple are the species of main interest in the covered countries. As from collected data, about 19.8% of landrace cultivation sites are in protected areas of the Natura 2000 network. We also got evidence that 16.7% and 19.3% of conservation varieties of agricultural species and vegetables are currently cultivated, respectively. Results of the GIS analysis allowed the identification of 1261 cells (25 km × 25 km) including all the cultivation sites, distributed across all European biogeographical regions. Data of this study constitute the largest ever produced database of in situ-maintained landraces and the first attempt to create an inventory for the entire Europe. The availability of such resource will serve for better planning of actions and development of policies to protect landraces and foster their use

Conformal mappings versus other power series methods for solving ordinary differential equations: illustration on anharmonic oscillators

The simplicity and the efficiency of a quasi-analytical method for solving nonlinear ordinary differential equations (ODE), is illustrated on the study of anharmonic oscillators (AO) with a potential $V(x) =\beta x^{2}+x^{2m}$ ($m>0$). The method [Nucl. Phys. B801, 296 (2008)], applies a priori to any ODE with two-point boundaries (one being located at infinity), the solution of which has singularities in the complex plane of the independent variable $x$. A conformal mapping of a suitably chosen angular sector of the complex plane of $x$ upon the unit disc centered at the origin makes convergent the transformed Taylor series of the generic solution so that the boundary condition at infinity can be easily imposed. In principle, this constraint, when applied on the logarithmic-derivative of the wave function, determines the eigenvalues to an arbitrary level of accuracy. In practice, for $\beta \geq 0$ or slightly negative, the accuracy of the results obtained is astonishingly large with regards to the modest computing power used. It is explained why the efficiency of the method decreases as $\beta$ is more and more negative. Various aspects of the method and comparisons with some seemingly similar methods, based also on expressing the solution as a Taylor series, are shortly reviewed, presented and discussed.Comment: 32 pages, 7 figures, 8 table

Reducing the Impact of Vehicles on the Environment by the Modernization of Transport Infrastructure

© Springer Nature Switzerland AG 2020. Along with a positive impact on the economy and social development, motorization has negative consequences, including noise pollution and air pollution from the exhaust gases of the urban environment by vehicles. The state of transport infrastructure and management systems has a significant impact on the parameters of traffic flows and the degree of their impact on the environment. Therefore, the development and applying of science-based methods for improving the road traffic management efficiency in urban areas by up-grading infrastructure facilities in difficult road network sections is an actual problem and is of considerable theoretical and practical interest. The article analyzed the problem areas of the road network of two large cities, similar in scale and planning solution, but with a certain specificity. The authors built simulation models of problem road sections based on a discrete-event approach using a traffic library. Computer experiments on the model showed that the data obtained is consistent with the results of field surveys. Propositions for the reconstruction of these sections were proposed Performing a computer experiment on a model with new parameters showed that in these areas there is considerable potential for improving parameters of the traffic flow, which will help to reduce the negative effect on the environment