Search results for "Sòl"
showing 10 items of 60 documents
Reduction of the frequency of herbaceous roots as an effect of soil compaction induced by heavy grazing in rangelands of SW Spain
2017
Rangelands in SW Spain constitute the most extensive ranching system on the Iberian Peninsula. During the last few decades, a significant increase in livestock numbers, along with a progressive substitution of cattle for sheep, have led to land degradation processes such as the reduction of grass cover and increased soil compaction in heavily grazed areas. Nevertheless, a better understanding of how soil compaction affects grass production is still needed. In this study, some of the effects of soil compaction due to heavy grazing are analysed, mainly the reduction of the frequency of herbaceous roots and its relationships with bulk density and soil penetration resistance. The study was carr…
Determination of enzymatic activities using a miniaturized system as a rapid method to assess soil quality
2014
Soil quality determination requires the analysis of a number of soil attributes using different approaches. In recent years, one of the most promising approaches has been the determination of enzymatic activities. Generally, only a few enzymes have been analysed and related with other parameters, such as total carbon, nitrogenous content or microbial biomass carbon. The aim of this work was to investigate the possible use of the API ZYM strip, a semi-quantitative miniaturised system that determines 19 enzymatic activities, to study soil quality. To this end, we tested the system in different soil types, including albicArenosols, mollicLeptosols, rendzicLeptosols, haplicLeptosols, and calcar…
Usos del sòl a la ciutat i llibertat d'establiment
2022
La tesi que es desenvolupa a aquest treball és que l’urbanisme, i més específicament la zonificació dels sòls, ha estat tradicionalment emprat per a controlar qüestions no només urbanístiques, sinó també socials i econòmiques, ja que permet solucions adaptades i cas per cas per als distints conflictes socials i urbans i perquè és l’instrument clau de què gaudixen els ens locals per a incidir de manera efectiva en les qüestions del seu interés. Per això, ara que les forces de la globalització amenacen tant la identitat, autenticitat i idiosincràsia de les ciutats com les concretes tècniques urbanístiques a través del reforçament de les llibertats econòmiques, es fa també necessari aprofundir…
Enseñanza de las ciencias : revista de investigación y experiencias didácticas
2006
Resumen basado en el de la publicación Resumen en inglés Se analizan diferentes enfoques para la introducción de los estudiantes a los conceptos básicos del enlace químico y la teoría de banda, así como errores relacionados con cada concepto. ESP
Comparison of social-ecological resilience between two grassland management patterns driven by grassland land contract policy in the Maqu, Qinghai-Ti…
2018
Embraced for decision-making, resilience has evolved as a meaningful term in areas such as ecology, the economy and society. After a policy of grassland contracts was implemented on the Qinghai-Tibetan Plateau, two grassland management patterns evolved: the multi-household management pattern (MMP) and the single-household management pattern (SMP). Within a resilience-driven perspective, this study compared the outcomes of these grassland management patterns by measuring their effects on the resilience of grazing, ecological, economic and social systems. Resilience indicators for each of the four systems were: grazing system (grazing space, transhumance, water source and reproduction); ecolo…
Characterization of gas flow through low-permeability claystone: laboratory experiments and two-phase flow analyses
2014
For the characterization of gas migration through a low-permeability clay host rock for deep underground repositories, a comprehensive understanding of the relevant phenomena of gas and fluid flow through low-permeability clay is required. The National Cooperative for the Disposal of Radioactive Waste (Nagra) in Switzerland has developed a comprehensive programme to characterize gas flow in low-permeability Opalinus Clay through laboratory tests and detailed numerical analyses for developing appropriate constitutive models. Laboratory tests were performed on cores by two different laboratories, the Laboratory for Soil Mechanics at EPFL and the Department of Geotechnical Engineering and Geos…
Add-On Effect of Postural Instructions to Abdominopelvic Exercise on Urinary Symptoms and Quality of Life in Climacteric Women with Stress Urinary In…
2021
The aim of this study was to investigate the add-on effect of postural instructions to an abdominopelvic exercise program on incontinence urinary symptoms (UI symptoms) and quality of life (QoL) in climacteric women with stress urinary incontinence (SUI). A randomized controlled trial was performed with a total of 40 climacteric women with SUI aged between 46 and 75 years old. Participants were randomly assigned to two groups: a group performing an abdominopelvic exercise program (AEP) (n = 20) and a group performing abdominopelvic exercise with the addition of postural instructions (AEPPI) (n = 20). Primary outcome measures were UI symptoms, UI impact and QoL related to UI (UI-QoL), measur…
Quality Analysis of YouTube Videos Presenting Pelvic Floor Exercises after Prostatectomy Surgery
2021
Background: Prostate cancer (PC) is a major cause of disease and mortality among men. Surgical treatment involving the removal of the prostate may result in temporary or permanent erectile dysfunction (ED) and urinary incontinence (UI), with considerable impact on quality of life. Pelvic floor muscle training (PFMT) is one of the recommended techniques for the prevention, treatment, and rehabilitation of postoperative complications. The aim of this observational study was to assess the quality of YouTube videos—accessible to any patient—related to exercises after prostatectomy surgery. Methods: A systematic search was performed on YouTube on 24 September 2020. One hundred and fifty videos w…
On the volumetric response of a compacted clay subjected to wetting and drying cycles
2009
Experimental evidence on the volumetric response of a compacted clay was collected in controlled suction oedometric tests, with the aim to assess the volumetric response of this soil when subjected to wetting and drying cycles. The overall soil behaviour seems mainly to depend on the double structural arrangement observed in the compacted specimens. Selected results are presented and discussed focusing on the influence of the stress history on the volumetric response. Test results are simulated by a double-structure suction-dependent elasto-plastic constitutive model, in which the mechanical response is related to micro and macrostructural deformations and their mutual interactions. The pro…
Straw uses trade-off only after soil organic carbon steady-state
2018
Soil organic matter (SOM) is the key for a healthy soil and a relevant property to achieve the sustainability on soil management. However, soils are still net exporters of organic matter. One example is the use of wheat straw residue for industrial and energy applications, which has gained attention in the last years. The offfarm use of this abundant and low cost resource should follow sustainability criteria to avoid soil degradation and SOM losses. Straw residue incorporation is recognized as a recommended management practice to control erosion and mitigate CO2 emissions by increasing SOM. The goal of this work was: i) to evaluate the steady-state carbon (C) level in relation to C input a…