Spatially variable hydrologic impact and biomass production tradeoffs associated with Eucalyptus (E. grandis) cultivation for biofuel production in Entre Rios, Argentina

Climate change and energy security promote using renewable sources of energy such as biofuels. High woody biomass production achieved from short-rotation intensive plantations is a strategy that is increasing in many parts of the world. However, broad expansion of bioenergy feedstock production may have significant environmental consequences. This study investigates the watershed-scale hydrological impacts of Eucalyptus (E. grandis) plantations for energy production in a humid subtropical watershed in Entre Rios province, Argentina. A Soil and Water Assessment Tool (SWAT) model was calibrated and validated for streamflow, leaf area index (LAI), and biomass production cycles. The model was used to simulate various Eucalyptus plantation scenarios that followed physically based rules for land use conversion (in various extents and locations in the watershed) to study hydrological effects, biomass production, and the green water footprint of energy production. SWAT simulations indicated that the most limiting factor for plant growth was shallow soils causing seasonal water stress. This resulted in a wide range of biomass productivity throughout the watershed. An optimization algorithm was developed to find the best location for Eucalyptus development regarding highest productivity with least water impact. E. grandis plantations had higher evapotranspiration rates compared to existing terrestrial land cover classes; therefore, intensive land use conversion to E. grandis caused a decline in streamflow, with January through March being the most affected months. October was the least-affected month hydrologically, since high rainfall rates overcame the canopy interception and higher ET rates of E. grandis in this month. Results indicate that, on average, producing 1 kg of biomass in this region uses 0.8 m of water, and the green water footprint of producing 1 m fuel is approximately 2150 m water, or 57 m water per GJ of energy, which is lower than reported values for wood-based ethanol, sugar cane ethanol, and soybean biodiesel

Convergence of soil nitrogen isotopes across global climate gradients

Quantifying global patterns of terrestrial nitrogen (N) cycling is central to predicting future patterns of primary productivity, carbon sequestration, nutrient fluxes to aquatic systems, and climate forcing. With limited direct measures of soil N cycling at the global scale, syntheses of the 15N:14N ratio of soil organic matter across climate gradients provide key insights into understanding global patterns of N cycling. In synthesizing data from over 6000 soil samples, we show strong global relationships among soil N isotopes, mean annual temperature (MAT), mean annual precipitation (MAP), and the concentrations of organic carbon and clay in soil. In both hot ecosystems and dry ecosystems, soil organic matter was more enriched in 15N than in corresponding cold ecosystems or wet ecosystems. Below a MAT of 9.8°C, soil δ15N was invariant with MAT. At the global scale, soil organic C concentrations also declined with increasing MAT and decreasing MAP. After standardizing for variation among mineral soils in soil C and clay concentrations, soil δ15N showed no consistent trends across global climate and latitudinal gradients. Our analyses could place new constraints on interpretations of patterns of ecosystem N cycling and global budgets of gaseous N loss

EVS Trend File 1981-2017 – Sensitive Dataset

The European Values Study is a large-scale, cross-national and longitudinal survey research program on how Europeans think about family, work, religion, politics, and society. Repeated every nine years in an increasing number of countries, the survey provides insights into the ideas, beliefs, preferences, attitudes, values, and opinions of citizens all over Europe. The EVS Trend File 1981-2017 is constructed from the five EVS waves and covers almost 40 years. In altogether 160 surveys, more than 224.000 respondents from 48 countries/regions were interviewed. It is based on the updated data of the EVS Longitudinal Data File 1981-2008 (v.3.1.0) and the current EVS 2017 Integrated Dataset (v.5.0.0). For the EVS Trend File, a Restricted-Use File (ZA7504) is available in addition to the (factually anonymised) Scientific-Use File (ZA7503). The EVS Trend File – Sensitive Dataset (ZA7504) is provided as an add-on file. In addition to a small set of admin and protocol variables needed to merge with the SUF data, the Sensitive Dataset contains the following variables that could not be included in the scientific-use file due to their sensitive nature: W005_3 Job profession/industry (3-digit ISCO88) - spouse/partner EVS 2008W005_3_01 Job profession/industry (3-digit ISCO08) - spouse/partner EVS 2017W005_4 Job profession/industry (4-digit ISCO88) - spouse/partner EVS 2008X035_3 Job profession/industry (3-digit ISCO88) – respondent EVS 1999, EVS 2008 X035_3_01 Job profession/industry (3-digit ISCO08) - respondent EVS 2017X035_4 Job profession/industry (4-digit ISCO88) – respondent EVS 1999, EVS 2008 x048c_n3 Region where the interview was conducted (NUTS-3): NUTS version 2006 EVS 2008X048J_N3 Region where the interview was conducted (NUTS-3): NUTS version 2016 EVS 2017X049 Size of town (8 categories) EVS 2008, EVS 2017 Detailed information on the anonymization process in the EVS Trend File is provided in the EVS Trend File Variable Report