Spatiotemporal variability of hydrologic soil properties and the implications for overland flow and land management in a peri-urban Mediterranean catchment

Planning of semi-urban developments is often hindered by a lack of knowledge on how changes in landuse affect catchment hydrological response. The temporal and spatial patterns of overland flow source areas and their connectivity in the landscape, particularly in a seasonal climate, remain comparatively poorly understood. This study investigates seasonal variations in factors influencing runoff response to rainfall in a peri-urban catchment in Portugal characterized by a mosaic of landscape units and a humid Mediterranean climate. Variations in surface soil moisture, hydrophobicity and infiltration capacity were measured in six different landscape units (defined by land-use on either sandstone or limestone) in nine monitoring campaigns at key times over a one-year period. Spatiotemporal patterns in overland flow mechanisms were found. Infiltration-excess overland flow was generated in rainfalls during the dry summer season in woodland on both sandstone and limestone and on agricultural soils on limestone due probably in large part to soil hydrophobicity. In wet periods, saturation overland flow occurred on urban and agricultural soils located in valley bottoms and on shallow soils upslope. Topography, water table rise and soil depth determined the location and extent of saturated areas. Overland flow generated in upslope source areas potentially can infiltrate in other landscape units downslope where infiltration capacity exceeds rainfall intensity. Hydrophilic urban and agricultural-sandstone soils were characterized by increased infiltration capacity during dry periods, while forest soils provided potential sinks for overland flow when hydrophilic in the winter wet season. Identifying the spatial and temporal variability of overland flow sources and sinks is an important step in understanding and modeling flow connectivity and catchment hydrologic response. Such information is important for land managers in order to improve urban planning to minimize flood risk

Assessment of surface hydrologic properties on a small urbanized mediterranean basin : Experimental design and first results

This paper presents the methodology and the first results of a study that is being developed in the Ribeira dos Covões micro-catchment, located in central Portugal, to study the impact of different land uses and the urbanization process on spatio-temporal hydrological changes based on a multi-scale approach. The aim of this study is to contribute for a better understanding on how land use changes impact hydrological processes. This is critical for predicting urban floods in fast urbanized areas and their mitigation (e.g. real-time flood warning procedures), which has become crucial for planning, management, and supporting the sustainable development of the basin

Avaliação no campo de feromônio sexual sintético de Elasmopalpus lignosellus (Lepidoptera: pyralidae).

Foram avaliadas, no campo a eficiencia de tres formulacoes do feromonio de Elasmopalpus lignosellus (Zeller, 1848) na captura de machos da especie. Destas, duas foram importadas dos E.U.A., sendo uma comercial do tipo laminado plastico da "Hercon Divison Health Chem. Corporation:, e a outra do tipo septo de borracha, cedida pelo USDA-ARS. A terceira formulacao foi produzida na Universidade Federal de Vicosa com componentes sintetizados no Departamento de Quimica da Universidade Federal de Sao Carlos (Sao Paulo). Os resultados demonstraram que estas formulacoes, que continham as principais componentes de feromonio sexual de E. lignosellus, sintetizados com base na identificacao do feromonio de femeas que ocorrem no estado de Georgia (E.U.A.), foram ineficientes para atrair machos das especies na regiao do CNPMS-EMBRAPA, Sete Lagoas (MG), onde foram conduzidos estes experimentos. Acredita-se, com isto, que haja diferenca na composicao ou na proporcao dos diferentes componentes do feromonio sexual das populacoes de E. lignosellus destas duas diferentes localidades.199