STUDY OF AUTUMN-WINTER WEEDS IN PORTUGAL AND ITS ECOLOGICAL PREFERENCES

Planta Daninha

S. RamÔa¹  P. Oliveira E Silva¹  T. Vasconcelos¹  P. Fortes¹  J. Portugal¹ 

关键词: spontaneous flora;    Mediterranean climate;    ecological profiles;    active factors;    texture;    extractable phosphorus;    vegetação espontânea;    clima mediterrâneo;    perfis ecológicos;    fatores ativos;    textura;    fósforo extraível;   

DOI  :  10.1590/S0100-83582015000300001

来源: SciELO

【 摘 要 】

ABSTRACTThe 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.minorwas not related to the soil texture but showed preference for soils with medium phosphorus content.

【 授权许可】

CC BY   
 All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License