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Ajouter le résultat dans votre panierThe horizontal movement of seeds in arable soil by differnet soil cultivation methods / Edward Jon Marshall in Journal of applied ecology, 36 ([01/01/1999])
Titre : The horizontal movement of seeds in arable soil by differnet soil cultivation methods Type de document : Électronique Auteurs : Edward Jon Marshall (1952-), Auteur Année de publication : 1999 Article en page(s) : 443-454 Langues : Anglais (eng) Catégories : [CBNPMP-Thématique] Malherbologie Résumé : To assess the impact of soil cultivation on the horizontal movement of seeds in arable soil, plastic beads and barley or triticale seeds were used as seed models. Different coloured beads were introduced in the field immediately before each of five cultivations: ploughing, two tine cultivations, harrowing and seed drilling. Beads were recovered from 20-cm soil cores divided into four 5-cm deep soil horizons. After a typical cultivation sequence of five operations, beads were found up to 15m from their source, although most beads were found within 2m. Most beads were recovered from the surface 5cm of the soil profile, except for those introduced onto the surface or at 20cm depth before ploughing, which were concentrated below 10cm. Regression analysis was used to determine the pattern of bead movement by seed drilling. A novel analysis using Fast Fourier Transforms established the probability distribution functions of the remaining cultivation operations for horizontal movement. Using the final seed distributions, the effects of each cultivation were sequentially deconvoluted and the probability distribution functions smoothed. The proportions of beads moved were also calculated. Ploughing and seed drilling moved seed the least distance compared with other cultivations. The mean distances moved were 0·36m and 0·26m, respectively. Tine cultivations moved beads 0·71m and 1·21m, while harrowing moved seed a mean distance of 1·58m. Cultivation sequences based on ploughing are likely to limit seed movement in soil. The Fourier deconvolution approach has potential for predicting future seed distributions and thus the spatial behaviour of weed patches within fields. Lien pérenne : DOI : 10.1046/j.1365-2664.1999.00412.x Permalink : https://biblio.cbnpmp.fr/index.php?lvl=notice_display&id=144360
in Journal of applied ecology > 36 [01/01/1999] . - 443-454Marshall, Edward Jon (1952-) 1999 The horizontal movement of seeds in arable soil by differnet soil cultivation methods. Journal of applied ecology, 36: 443-454.Documents numériques
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Article (1999)URL
Titre : The impact of changing the season in which cereals are sown on the diversity of the weed flora in rotational fields in Denmark Type de document : Imprimé Auteurs : Anna Bodil Hald Année de publication : 1999 Article en page(s) : 24-32 Langues : Anglais (eng) Catégories : [CBNPMP-Thématique] Messicole Résumé : Surveys have shown that there has been a dramatic decrease in the weed flora of fields under rotational cultivation during the last 30 years. This trend has been particularly noticeable in winter cereals, a crop of increasing importance in the landscape. The weed flora of spring and winter cereals was compared in 19 unsprayed fields during a 5-year study to test the hypothesis that cereal type exerts no effect on the flora or on the absolute and relative abundance of single species. Plant and species densities, and accumulated species richness, were lower in winter than in spring cereals. Floristic similarity was greater among spring cereal fields and between spring and winter cereals within the same fields than among winter cereal fields. Species that occurred with unequal density in spring and winter cereals occurred at higher densities in the spring cereals; these species germinated mainly in the spring. However, for a few species the relative plant abundance was highest in winter cereals; these species were able to germinate both in the spring and autumn. Some species – on the relative scale – occurred indifferently of season of sowing; all but one of these species were able to germinate both in the spring and autumn. Plant species and taxa that are important food resources for arthropod herbivores occurred at greater densities in spring than in winter cereals and, in addition, occurred with the highest relative abundance in spring cereals. Change in land use from spring to winter cereals involves not only an immediate reduction of more than 25% in the density of plants and species, but also a change and increased uncertainty in the composition of the weed flora. These findings may have serious implications for the ecology of wildlife in the agricultural landscape. Lien pérenne : DOI : 10.1046/j.1365-2664.1999.00364.x Permalink : https://biblio.cbnpmp.fr/index.php?lvl=notice_display&id=149201
in Journal of applied ecology > 36 [01/01/1999] . - 24-32Hald, Anna Bodil 1999 The impact of changing the season in which cereals are sown on the diversity of the weed flora in rotational fields in Denmark. Journal of applied ecology, 36: 24-32.Documents numériques
Article (1999)URL
