Appropriate soil management is essential to promote less intensive and more environmentally sustainable production systems for ligneous crops. This paper reports field experiments performed on olive plantations and vineyards with the following objectives: to evaluate the efficacy of different management systems with respect to traditional systems used in semjarid, continental environments; to establish the most appropriate herbaceous cover (weeds, subclover) in terms of reduced erosion and competition for water and nutrients; and to assess the efficacy of different strategies aimed at increasing the nitrogen and organic matter content of these soils, including the cultivation and subsequent burial of vetch in olive plantations, the burial of chopped, dry vine branches in vineyards, and the use of a subclover cover. Experimental plots were subjected to the following treatments: 1) vetch cover (Vicia saliva, 100 kglha) for olive plantations; 2) burial of dry vine branches for vineyards; 3) traditional tillage, leaving the soil free of weeds all year-round; 4) non-tillage plus subclover covers (Trifolium sublerraneum, a mixture of Nungarin, Daliak, and Esperance cultivars at 15 kg/ha); 5) non-tillage plus weed covers formed by the growth of spontaneous vegetation followed by mechanically mowing at the beginning and middle of spring and; 6 ) non-tillage accompanied by the use of herbicides. The soil water content of the plots was determined gravimetrically on samples obtained at depths of 0-20, 20-40 and 40-60 cm. The different vegetation covers were assessed in terms of coverage achieved and conservation of biodiversity. Finally, the impact of the different treatments on chemical (O.M, N, P and K) and biochemical (ATP, COjATP) fertility was also examined. lt was observed that as early as the first year, the plant covers provided the crops with protection against erosiono During years of normal rainfall, these covers showed no significant competition with the ligneous plants, particularly before becoming too dense. The management strategy used favoured the presence and abundance of spontaneous legumes in the olive plantation. Subclover planted in the vineyard was notably persistent. Despite the short study period, effects on soil fertility are starting to emerge, with indications of microbial regeneration. This was of greatest intensity in plots sown with subclover.

14 páginas y 7 tablas estadísticas

Peer reviewed

132IRN-21