Der Zeitaspekt in der Landes- und Regionalplanung Erarbeitungsfristen, Planveralterung, Prognoseunsicherheit, Rechtsprobleme

TIB: RN 5044 (101) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Brazil's current and future land balances: Is there residual land for bioenergy production?

This study presents a new database of land use categories in Brazil at a spatial resolution of 30 arc-second (about 1 km^2). The spatial representation of current major land uses formally combines agricultural statistics from Brazil's latest census of the year 2006 at micro-region level and the Food and Agriculture Organization 2010 forest statistics with spatial land cover data sets. Spatial allocation ("downscaling") algorithms were applied to obtain a spatial distribution of seven major land use categories. Remaining shares in each grid-cell were termed residual land, and were categorized according to legal protection status, biodiversity value, and whether they belong to the territory of the Amazon biome. We found a total of 84 Mha residual land of which 37 Mha occurred outside the territory of the Amazon biome and was neither legally protected nor categorized as highly biodiverse land. The 37 Mha "available residual land" equates to 4.4% of Brazil's geographical area and to 50% of its current cultivated land area. We assessed land quality using the Agro-ecological Zones modelling framework provides land suitability and productivity estimates of the available residual land. Nearly one-third of land emerged of prime quality and is therefore promising for biofuel feedstock production. Analysis of potential food-fuel competition suggests that until 2030 productivity improvements on current pastures could accommodate land demand for Brazil's increasing cattle herd and expanding croplands. If these productivity increases could be achieved on current agricultural land, residual land could provide areas for the sustainable expansion of biofuel feedstock production

Field-induced valence transition in EuPtP1−xAsx

The ternary compound EuPtP exhibits two valence transitions at T1 = 235 K and T2 = 190 K. In order to examine a field-induced valence transition of Eu, we synthesized EuPtP1−xAsx compounds with 0.05 ≤ x ≤ 0.5 and studied the magnetic and valence behavior. The substitution of As for P increases the lattice volume linearly and decreases both valence transition temperatures, T1 and T2, in contrast to the behavior under external pressures. The magnetization process in a pulsed magnetic field revealed that EuPtP0.5As0.5 exhibits an onset of metamagnetic transition above 50 T with a large hysteresis, which evidences a first-order field-induced valence transition. The analysis of the magnetization curves of x = 0.5 at various temperatures has demonstrated that the field-induced transition is essentially the same as the transition induced by temperature at T1