3 resultados para Climate-Vegetation Relationships

em Repositório Científico da Universidade de Évora - Portugal


Relevância:

30.00% 30.00%

Publicador:

Resumo:

tWater use control methods and water resources planning are of high priority. In irrigated agriculture, theright way to save water is to increase water use efficiency through better management. The present workvalidates procedures and methodologies using remote sensing to determine the water availability in thesoil at each moment, giving the opportunity for the application of the water depth strictly necessaryto optimise crop growth (optimum irrigation timing and irrigation amount). The analysis is applied tothe Irrigation District of Divor, Évora, using 7 experimental plots, which are areas irrigated by centre-pivot systems, cultivated to maize. Data were determined from images of the cultivated surface obtainedby satellite and integrated with atmosphere and crop parameters to calculate biophysical indicatorsand indices of water stress in the vegetation—Normalized Difference Vegetation Index (NDVI), Kc, andKcb. Therefore, evapotranspiration (ETc) was estimated and used to calculate crop water requirement,together with the opportunity and the amount of irrigation water to allocate. Although remote sensingdata available from satellite imagery presented some practical constraints, the study could contribute tothe validation of a new methodology that can be used for irrigation management of a large irrigated area,easier and at lower costs than the traditional FAO recommended crop coefficients method. The remotesensing based methodology can also contribute to significant saves of irrigation water.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Vegetation series, defined as the sequence of stages in a sucession, and know as sigmetum (synassociation), describes the set of plant communities or stages that can be found in similar tesselar spaces as a result of the sucession process. This establishes the concept of vegetation series; a climatophilous series is one that depends on the climate, whereas an edaphoxerophilous series depends on the dryness of the soil, and is found on crests, spurs, ledges and limestone and siliceous rock fields. Edaphohygrophilous series are located in valleys, dry water courses and river terraces, and depend on the water present in the soil, which may become temporarily flooded and thus condition the temporihygrophilous series; they represent the transition between the clearly edaphohygrophilous and climatophilous series. The vegetation permaseries represents the perennial communities of permatesselae or similar permatesselar complexes, as occurs in polar territories, hyperdesert, high-mountain peaks, and non-stratified communities lacking in serial communities. The edaphoxerophilous series may include -in addition to the series head- permaseries (permanent communities) and other habitats, such as annual and crevice habitats. A territory behaves undergoes soil-loss phenomena it may become an edaphoseries, if the loss of the soil factor produces a situation of rocky crest. Thus the edaphoseries may act as dynamic transitional stage between the climatophilous series and the permaseries.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Climate in the classroom is one of the determining factors in the development of practices in Inclusive Education. Many factors contribute to the climate in the classroom. However, there are predominance on affective-relational factors, with impact on action, norms and values, social interactions and learning processes. In this paper, the authors reflect on four studies which aim to identify and evaluate the relationship between several agents in the teaching–learning process (regular teachers, special education teachers and peer students) and the students with Autism, Cerebral Palsy, Mental Disability and Attention Deficit Hyperactivity Disorder. The studies were held in Primary Portuguese schools. The results are presented and discussed in their similarities and differences. The discussion shows that relationships between teachers and children with Special Education Needs (SEN) differ from those between teachers and typical children, but also according to different SEN. In general, there are not significant differences between regular teachers and special education teachers