Estado de fertilidad de los suelos de Entre Ríos : principales limitaciones

p.15-19

Características hídricas de los principales suelos de Entre Ríos con especial énfasis en vertisoles

p.133-137

Actividad biológica y descomposición de rastrojo de trigo (14C) en suelos con distintas cantidades de sustrato y densidades aparentes

p.193-199

Los pastizales pioneros vivaces de los suelos serpentínicos del noroeste ibérico

Se estudian comparativamente los pastizales pioneros vivaces de los suelos serpentínicos de Galicia y del nordeste de Portugal, describiéndose la asociación Sagino merinoi-Plantagínetum radicatae nova.

Valoración de impacto ambiental por pesticidas agrícolas.

El uso de agroquímicos en Argentina se ha fortalecido junto con la expansión agrícola. El objetivo de este trabajo es la elaboración de una metodología para calcular el impacto ambiental que los pesticidas causan en el medio ambiente teniendo en cuenta los siguientes factores: "ecotoxicología": categoría toxicológica, toxicidad en abejas, aves y peces; "Toxicidad humana": carcinogenicidad, neurotoxicidad, alteraciones endocrinas, genotoxicidad y capacidad irritativa; "Comportamiento ambiental": la persistencia en el agua / sedimento, persistencia en el suelo y bioconcentración. Estos factores fueron clasificados como bajo, medio, alto o muy alto, de acuerdo con su nivel de toxicidad. Los resultados indican que los plaguicidas más tóxicos son los insecticidas. La mayoría de los pesticidas utilizados son la toxicidad media (43,75%), seguido de baja y alta toxicidad (21,88%) y, los de muy alta toxicidad (12,5%). La metodología propuesta podría ser utilizada como una herramienta de monitoreo, gestión o educación ambiental.

Assessing the combined effect of land management and wildfire on runoff and soil erosion in north central Portugal

Strong and sometimes extreme responses in runoff and soil erosion following wildfires have been reported worldwide. However, in the case of North-Central Portugal, little research had been carried out regarding the hydrologic and erosive impacts of several land management activities in recently burnt areas (such as ground preparation, post-fire logging or post-fire mitigation treatments). This study aims to assess post-fire runoff and soil erosion response on Eucalypt and Maritime pine plantations during the first, second and third years following wildfires. The effect of several pre-fire ground preparation operations (ploughed down-slope, contour ploughed and inclined terraces), post-fire logging activities (on both the eucalypt and pine plantations), as well as the application of hydromulch (a post-fire emergency treatment) on overland flow and soil erosion were compared to burnt but undisturbed and untreated areas. The intensive monitoring of runoff, soil erosion and selected soil properties served to determine the main factors involved in post-fire runoff and soil erosion and their spatial and temporal variation. Soil water repellency deserved special attention, due to its supposed important role for overland flow generation. Repeated rainfall simulation experiments (RSE’s), micro-scale runoff plots and bounded sediment fences were carried out and/or installed immediately after the wildfire on seven burnt slopes. Micro-scale runoff plots results under natural rainfall conditions were also compared to the RSE’s results, which was useful for assessing the representativeness of the data obtained with artificial rainfall. The results showed comparable runoff coefficient (20-60%) but lower sediment losses (125-1000 g m-2) than prior studies in Portugal, but especially outside Portugal. Lower sediment losses were related with the historic intensive land use in the area. In evaluating these losses, however, the shallowness and stoniness of the soils, as well as the high organic matter fraction of the eroded sediments (50%) must not be overlooked. Sediment limited erosion was measured in all the ploughed sites, probably due to the time since ploughing (several years). The disturbance of the soil surface cover due to post-fire logging and wood extraction substantially increased sediment losses at both the pine and eucalypt sites. Hydromulch effectiveness in reducing the runoff (70%) and sediment losses (83%) was attributed to the protective high coverage provided by hydromulch. The hydromulch significantly affected the soil cover and other soil properties and these changes also reduced the soil erosion risk. The rainfall amount was the main factor explaining the variance in runoff. However, a shift from rainfall amount to rainfall intensity was detected when either the surface cover or the infiltration capacity (hydrophilic conditions) increased. Sediment losses were controlled by rainfall intensity and surface cover. The role of soil water repellency on runoff generation was not consistent; the overall repellency levels alone were not enough to assess its hydrological impact. Soil water repellency explained runoff generation in the specific-sites model better than in the overall model. Additionally, soil moisture content was a better predictor for soil water repellency than antecedent rainfall. The natural rainfall results confirmed that RSE’s were able to capture the specific sediment losses and its organic matter content as well as the differences between the ploughed and unploughed sites. Repeated RSE’s also captured the seasonal variations in runoff and sediment losses attributed to soil water repellency. These results have implications for post-fire soil erosion modelling and soil conservation practices in the region, or areas with the same land use, climate and soil characteristics. The measured sediment loss, as well as the increasing frequency of ploughing in recently burnt and unburnt eucalypt stands, suggests ploughing is not an effective as a soil conservation measure. Logging activities with less impact are recommended in order to maintain the forest litter protecting the soil surface. Due to its high effectiveness in reducing runoff and soil erosion, hydromulch is recommended for highly sensitive and vulnerable areas.

A desagregação espacial de dados agrícolas: aplicação de uma abordagem baseada na máxima entropia ao concelho de Castelo de Vide

Dissertação mest., Gestão Sustentável de Espaços Rurais, Universidade do Algarve, 2009

Análise das alterações ao nível da estrutura das explorações agrícolas da Região Algarve e respectivo tecido empresarial, decorrentes da aplicação dos apoiso comunitários, com especial incidência no período 1994/99

Dissertação de mest., Gestão Empresarial, Faculdade de Economia, Univ. do Algarve, 2001

Tecnologias da informação e electrónica aplicadas às estufas agrícolas

Ao longo dos últimos anos tem-se verificado uma tendência para a intencificação da produção, redução dos custos e melhoria na gestão dos processos produtivos. A complexidade dos fsctores implicados na obtenção destes objectivos torna indispensável, para poder gerir todo o sistema, que se recorra a um bom suporte informático, tanto em hardware como em software.

Modelos e estratégias de controlo ambientais para estufas agrícolas

For a greenhouse with a double polyethylene cover, it will be presented a dynamic climate transfer function and an adaptive controller for the air temperature. The model employ data acquired from the outside weather and from the heating and cooling inputs.

Estudo de novas técnicas de caracterização da resposta eléctrica em (Bio)sensores (para detecção de componentes agrícolas)

Faculdade de Ciências e Tecnologia – Universidade Nova de Lisboa Departamento de Engenharia Electrotécnica Tese de mestrado

Red nacional para el estudio de los incendios forestales y sus efectos en los suelos – RIS./ Rede nacional para o estudo dos Incêndios florestais e seus efeitos nos Solos

En enero de 2014, continuando con la intención expresada en Guimarães (Portugal), en noviembre de 2013, durante la VII Reunión de la Geografía Física y Medio Ambiente (EGFA VII), la Asociación Portuguesa de Prevención de Riesgos y Seguridad (RISCOS) creó las condiciones para el establecimiento de una sección temática dedicada al estudio de los efectos de los incendios sobre los suelos y que vendría a ser conocida “Red Nacional para el Estudio de los Incendios Forestales y sus Efectos sobre los Suelos” (RIS). Esta fue una iniciativa inspirada en Fuegored (Red Temática Nacional Efectos de los Incendios Forestales sobre los Suelos) y que, de esta manera, desea establecer una red nacional de investigadores con el fin de facilitar la promoción y difusión de los resultados de sus pesquisas científicas sobre este tema, realizadas en Portugal, así como la interacción entre el mundo científico y el manejo forestal . La RIS fue fundada por 12 miembros, que representan 7 universidades portuguesas y en la actualidad cuenta con 23 miembros de 9 universidades y escuelas politécnicas. Se espera que crezca y que puede añadir todos los que participan en la investigación científica de los incendios forestales y sus efectos en los suelos.

A política agrícola comum (PAC) e o comércio internacional - estudo econométrico do efeito da PAC sobre as exportações agrícolas portuguesas para a União Europeia (1975-2012)

Dissertação apresentada ao Instituto Superior de Contabilidade e Administração do Porto para obtenção do Grau de Mestre em Empreendedorismo e Internacionalização Orientadora: Professora Doutora Maria Clara Ribeiro Coorientadora: Mestre Maria Luísa Verdelho Alves

Espaços Agrícolas em Áreas Peri-urbanas - Tipologias e Planeamento na Área Metropolitana de Lisboa

Dissertação apresentada para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Gestão do Território, área de especialização em Planeamento e Ordenamento do Território