How to assess future agricultural performance under climate change? A case-study on the Veneto region

In this paper, we have constructed and tested a simple methodology for assessing and predicting climate change effects on agricultural yields. The methodology follows two steps. First, we econometrically estimate the marginal product of key production inputs (e.g., labor and land), through the estimation of production functions. Then, we predict future agricultural sector performance, by assuming a future with climate-induced changes in the land use and in agricultural labor use, under different IPCC scenarios. We also assume that no dramatic technological change in agriculture production will occur in the near future, so that the selected inputs will present the same marginal product. We assume that the agricultural sector might develop differently under different climate change-induced scenarios and that the use of land and labor will change accordingly. In this way, we are able to compute predictions on the agricultural sector performance in the future, under very different circumstances. We apply the methodology for predicting the sector performance of the Veneto region in 2030. Results differ according to the selected IPCC scenario and consequent input use variations. In the selected case study, for instance, land presents a very high productivity and climate-induced changes in the land use might dramatically (positively and negatively) affect agricultural yields under different IPCC scenarios. In this perspective, the climate change adaptation and mitigation policies and options should primarily aim at the preservation of land productivity in Veneto

Holocenska sedimentacija u solinskom kanalu (Mljetska jezera, Jadransko more)

A 103 cm long core from the Soline Channel (Mljet Island, Adriatic Sea), which is at present a surface connection between the peculiar marine Mljet Lakes and the open sea, indicates substantial changes of the sedimentary environment in the Holocene. In the layer dated to 4,600 B.P., 25–30 cm below the bottom (which is at 2.8 m depth), freshwater algae represented by species of Chara/Nitella were found along with the gastropod Limnea stagnalis. This dominantly brackish sediment extends from 10 to 60 cm below the bottom. Above that interval marine sediment was found and below it quartz dominated the subareal or freshwater sediment. This indicates that the surface marine connection between Mljet Lakes and the sea was established after deposition of freshwater/brackish sediments i.e. not earlier than ca. 4 kyr B.P.Jezgra dugačka 103 cm izvađena iz kanala Soline (otok Mljet, Jadransko more), koji je danas površinska veza između jedinstvenih morskih Mljetskih jezera i otvorenog mora, ukazuje na bitne promijene taložnog okoliša u holocenu. U sloju čija je starost procijenjena na 4,600 godina, 25–30 cm ispod dna (koje se nalazi na dubini od 2.8 m), nađene su slatkovodne alge iz roda Chara/Nitella zajedno s puževima Limmnea stagnalis. Ti pretežno bočati sedimenti protežu se od 10 do 60 cm ispod dna. Iznad njih nalaze se marinski sedimenti a ispod kopneni ili slatkovodni sedimenti. To ukazuje da je površinska veza morem između Mljetskih jezera i otvorenog mora uspostavljena nakon taloženja slatkovodnih/bočatih sedimenata tj. ne prije oko 4 tisuće godina

REVIEW OF THE EXPERIMENTAL SETTING OF POLYETHYLENE BAGS - COLLECTORS FOR COLLECTING THE SHELLFISH LARVAE

U radu se opisuju i analiziraju dosadašnja istraživanja u vezi s eksperimentalnim postavljanjem polietilenskih vreća kao kolektora za prikupljanje mlađi školjkaša. Ukratko se opisuju osnove tehnologije uzgoja školjkaša te se iscrpnije obrađuju literaturni podatci u vezi s mjestom, sezonom i načinom postavljanja eksperimentalnih kolektora. Rezultati dosadašnjih istraživanja mogu se iskoristiti kao odrednice, a za razvoj komercijalnog uzgoja školjkaša na svakom se novom lokalitetu preporučuje eksperimentalno postavljanje kolektora.This work describes and analyses former researches regarding the experi mental setting of polyethylene bags as collectors for collecting the shellfish fry. Basic shellfish cultivation technologies are being briefly described and the literature data regarding the place, season and way of setting the experimental collectors are being detailed. The results of the former researches can be used as references while for the development of the commercial shellfish cultivation on each new location the experimental collec tor setting is recommended

Differential equation for four-point correlation function in Liouville field theory and elliptic four-point conformal blocks

Liouville field theory on a sphere is considered. We explicitly derive a differential equation for four-point correlation functions with one degenerate field $V_{-\frac{mb}{2}}$. We introduce and study also a class of four-point conformal blocks which can be calculated exactly and represented by finite dimensional integrals of elliptic theta-functions for arbitrary intermediate dimension. We study also the bootstrap equations for these conformal blocks and derive integral representations for corresponding four-point correlation functions. A relation between the one-point correlation function of a primary field on a torus and a special four-point correlation function on a sphere is proposed

Boundary One-Point Functions, Scattering, and Background Vacuum Solutions in Toda Theories

The parametric families of integrable boundary affine Toda theories are considered. We calculate boundary one-point functions and propose boundary S-matrices in these theories. We use boundary one-point functions and S-matrix amplitudes to derive boundary ground state energies and exact solutions describing classical vacuum configurations.Comment: 20 pages, LaTe

Exact and semiclassical approach to a class of singular integral operators arising in fluid mechanics and quantum field theory

A class of singular integral operators, encompassing two physically relevant cases arising in perturbative QCD and in classical fluid dynamics, is presented and analyzed. It is shown that three special values of the parameters allow for an exact eigenfunction expansion; these can be associated to Riemannian symmetric spaces of rank one with positive, negative or vanishing curvature. For all other cases an accurate semiclassical approximation is derived, based on the identification of the operators with a peculiar Schroedinger-like operator.Comment: 12 pages, 1 figure, amslatex, bibtex (added missing label eq.11

Vector coherent state representations, induced representations, and geometric quantization: I. Scalar coherent state representations

Coherent state theory is shown to reproduce three categories of representations of the spectrum generating algebra for an algebraic model: (i) classical realizations which are the starting point for geometric quantization; (ii) induced unitary representations corresponding to prequantization; and (iii) irreducible unitary representations obtained in geometric quantization by choice of a polarization. These representations establish an intimate relation between coherent state theory and geometric quantization in the context of induced representations.Comment: 29 pages, part 1 of two papers, published versio

Cultivation area affects the presence of fungal communities and secondary metabolites in Italian durum wheat grains

In this study, durum wheat kernels harvested in three climatically different Italian cultivation areas (Emilia Romagna, Umbria and Sardinia) in 2015, were analyzed with a combination of different isolation methods to determine their fungal communities, with a focus on Fusarium head blight (FHB) complex composition, and to detect fungal secondary metabolites in the grains. The genus Alternaria was the main component of durum wheat mycobiota in all investigated regions, with the Central Italian cultivation area showing the highest incidence of this fungal genus and of its secondary metabolites. Fusarium was the second most prevalent genus of the fungal community in all cultivation environments, even if regional differences in species composition were detected. In particular, Northern areas showed the highest Fusarium incidence, followed by Central and then Southern cultivation areas. Focusing on the FHB complex, a predominance of Fusarium poae, in particular in Northern and Central cultivation areas, was found. Fusarium graminearum, in the analyzed year, was mainly detected in Emilia Romagna. Because of the highest Fusarium incidence, durum wheat harvested in the Northern cultivation area showed the highest presence of Fusarium secondary metabolites. These results show that durum wheat cultivated in Northern Italy may be subject to a higher FHB infection risk and to Fusarium mycotoxins accumulation

Quantum singular oscillator as a model of two-ion trap: an amplification of transition probabilities due to small time variations of the binding potential

Following the paper by M. Combescure [Ann. Phys. (NY) 204, 113 (1990)], we apply the quantum singular time dependent oscillator model to describe the relative one dimensional motion of two ions in a trap. We argue that the model can be justified for low energy excited states with the quantum numbers $n\ll n_{max}\sim 100$, provided that the dimensionless constant characterizing the strength of the repulsive potential is large enough, $g_*\sim 10^5$. Time dependent Gaussian-like wave packets generalizing odd coherent states of the harmonic oscillator, and excitation number eigenstates are constructed. We show that the relative motion of the ions, in contradistinction to its center of mass counterpart, is extremely sensitive to the time dependence of the binding harmonic potential, since the large value of $g_*$ results in a significant amplification of the transition probabilities between energy eigenstate even for slow time variations of the frequency.Comment: 19 pages, LaTeX, 5 eps-figures, to appear on Phys. Rev. A, one reference correcte