Reiley D.K.,University of Wisconsin - Madison |
Breshears D.D.,Institute of the Environment |
Zedler P.H.,University of Wisconsin - Madison |
Ebinger M.H.,Los Alamos National Laboratory |
Meyer C.W.,Los Alamos National Laboratory
Journal of Arid Environments | Year: 2010
Soil carbon often varies significantly among vegetation patch types, but less known is how the size and species of plants in the tree canopy patches and the cover types of the intercanopy patches affect the carbon storage, and whether vegetation characteristics affect storage in adjacent patches. To assess this, we measured fine-fraction soil carbon in a semiarid woodland in New Mexico USA for canopy patches of two co-dominant woody species, Pinus edulis and Juniperus monosperma that were paired with intercanopy patch locations covered by herbaceous grass (Bouteloua gracilis) or bare ground. Soil carbon at shallow depths was greater in canopy than intercanopy patches by a factor of 2 or more, whereas within intercanopy patches soil carbon in grass locations exceeded that in bare locations only after accounting for coarse-fraction carbon. Hypothesized differences among canopy patches associated with species or size were not detected (although some size-depth interactions consistent with expectations were detected), nor, importantly, were effects of species or size of woody plant on intercanopy soil carbon. The results are notable because where applicable they justify estimates of soil carbon inventories based on readily observable heterogeneity in above-ground plant cover without considering the size and species of the woody plants. © 2009 Elsevier Ltd. All rights reserved.
Shahbazi A.,Shahid Beheshti University |
Gonzalez-Olmos R.,Helmholtz Center for Environmental Research |
Gonzalez-Olmos R.,Institute of the Environment |
Kopinke F.-D.,Helmholtz Center for Environmental Research |
And 2 more authors.
Separation and Purification Technology | Year: 2014
Iron-containing zeolites were studied as adsorbents and heterogeneous Fenton-like catalysts for the removal of the non-ionic surfactant Triton® X-100 (TX-100) from water. Adsorption tests included a variety of zeolites with different structure types (ZSM5, Beta and Y) and SiO2/Al 2O3 ratios. Zeolites with 12-membered-ring channels and high molar ratio of SiO2/Al2O3, indicating higher surface hydrophobicity, proved to be the most suitable adsorbents for TX-100. For preparation of iron-loaded zeolites, a Beta zeolite with a molar ratio of SiO2/Al2O3 of 200 was selected, based on its excellent adsorption properties, and compared with a natural zeolite of clinoptilolite type. Batch experiments indicated that both Fe-zeolites are active in the heterogeneous Fenton-like oxidation of TX-100 at neutral pH. However, the synthetic Fe-Beta zeolite was preferable compared to the Fe-loaded natural zeolite with respect to catalytic activity and H2O 2 utilization efficiency, which was interpreted in terms of differences in iron speciation and adsorption properties towards TX-100. Fe-Beta (200) was successfully applied in two cycles of adsorption/oxidation steps in a column experiment. This study shows that Fe-loaded Beta zeolites with high hydrophobicity can be suitable materials for a combined approach of adsorption/wet peroxide oxidation of chemicals with relatively high molecular weight and chain-like molecule structure, such as the non-ionic surfactant TX-100. © 2014 Elsevier B.V. All rights reserved.
Hecht S.,Institute of the Environment
Land Use Policy | Year: 2010
Deforestation captures most of the headlines, but there are also processes of forest expansion that are widespread in Latin America. This paper explores why this process is so invisible. Globalization plays an increasingly important role in structuring rural economies. This paper analyses how global integration of many types, ranging from remittances, state transfers, skilling and markets produced forest recovery in peasant landscapes. © 2009 Elsevier Ltd. All rights reserved.
News Article | August 22, 2016
Brazil's Institute of the Environment and Natural Resources, Ibama, has decided not to award an environmental license for the Sao Luiz do Tapajos hydroelectric plant, effectively ending development of the controversial 8,000 MW project.
Cejudo-Figueiras C.,University of Leon |
Cejudo-Figueiras C.,Institute of the Environment |
Blanco S.,University of Leon |
Blanco S.,Institute of the Environment |
And 4 more authors.
Vie et Milieu | Year: 2010
The Water Framework Directive requires that the European Union countries determine the biological state of their waters with respect to sites of high quality. Although bioindicators have been widely applied in running waters and deep lakes throughout Europe, little is known about their applicability in shallow lakes and wetlands. The objective of this work is to check the effectiveness of epiphytic diatoms as indicators of the trophic state in two wetlands of Álava Province (N Spain). Diatom and water chemical samples were collected during summer and autumn 2007, following standard methodology. Stems of submerged macrophyte (Carex riparia, Iris pseudacorus, Veronica anagallis-aquatica) were sampled in each lake. Based on the number of statistically significant correlations between diatom indices and environmental factors, the SID index was show as the most suitable method to assess nutrients within these systems. SID was significantly correlated with TP, NTK and ammonium levels. Among three different plants, only the indices calculated from /. pseudacorus samples were significantly correlated with nutrients.