Study of Autumn-Winter Weeds in Portugal and Its Ecological Preferences

Abstract

-The conclusion of the dam project located in Alqueva, in Southern Portugal, has resulted in a significant increase of new irrigated areas, since 2006. This has meant that, in recent years, there have been progressive flora changes in farming systems traditionally implemented in the Alentejo region. The present work has analyzed the weed flora in an early stage of these changes, and the impact of environmental factors on the distribution of natural vegetation under Mediterranean climate conditions in the influence area of Alqueva. In 2007, 105 floristic surveys were carried out in autumn-winter crop plots or other soil use, and 264 species were identified. Families with higher expression were: Asteraceae, Poaceae, and Fabaceae. Only three species have been identified in more than half of farms, Avena sterilis, Phalaris minor and Lolium rigidum and they were part of the 15 species that revealed high and very high infestation degrees. Soil texture and extractable phosphorus have been determined as active ecological factors, according to the method of ecological profiles and Mutual Information. Therefore, these factores were those with the greatest influence on the species distribution. L. rigidum distribution showed to be associated with medium soil texture and A. sterilis distribution also showed to be associated with medium and fine soil texture soils, without showing ecological preference by extractable phosphorus. The distribution of P. minor was not related to the soil texture but showed preference for soils with medium phosphorus content.Keywords: spontaneous flora, Mediterranean climate, ecological profiles, active factors, texture, extractable phosphorus. Palavras-chave: vegetação espontânea, clima mediterrâneo, perfis ecológicos, fatores ativos, textura, fósforo extraível. RESUMO -A concretização do projeto da barragem do

Plant diversity in traditional agroecosystems of North Morocco

“…material 4) shows the dominance of five families (Asteraceae, Poaceae, Fabaceae, Caryophyllaceae and Brassicaceae), typically reflecting the overall Moroccan flora (Fennane and Ibn Tattou 2012) and the segetal flora in western and northern Morocco (Zidane et al 2010). These families also had higher expression in studies conducted in the northern Mediterranean region (Guillerm and Maillet 1982;Saavedra et al 1989;Hidalgo et al 1990;Dessaint et al 2001;Ramôa et al 2015;Fanfarillo et al 2020;Munoz et al 2020). The dominance of the Mediterranean chorotype in the Rif Mountains is in line with the figures for the entire Moroccan flora, two thirds of which are Mediterranean species, as well as with those found by Guillerm and Maillet (1982) for cereal fields in the western Mediterranean, and by Fanfarillo et al (2019a) for traditional agroecosystems in Italy.…”

Evaluation of weed flora changes in Portugal in a 10 year basis

“…These findings are similar to those observed for the most frequent species identified in Spain by Cirujeda et al (2011), namely L. rigidum and A. sterilis. According to Ramôa et al (2015), soil texture and soil phosphorus content had a significant effect on the species distribution. In particular, L. rigidum seems to be associated with medium soil texture and A. sterilis also showed a preference for medium and fine soil texture soils.…”