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The biodiversity of farmed landscapes is, in the context of agricultural intensification, a key aspect with regard to improving the sustainability of agroecosystems. Olive groves are undergoing rapid changes because of the spread of intensive farming systems, which may have negative environmental impacts. This paper reports a survey on the aboveground flora and seed banks in five olive groves located in Andalusia (Southern Spain). In this study, the following three management systems have been compared: no‐tillage, with the mowing of spontaneous weedy vegetation; no‐tillage, with the mowing of planted cover crops (Poaceae); and conventional tillage practices. Results showed that coverage and an abundance of vegetation are favored by spontaneous weedy vegetation with mowing management, while the richness of aboveground species was affected by landscape diversity and the presence of edges, which increases the richness and diversity of aboveground flora species in olive groves. Seed bank composition showed a low relationship with aboveground flora in the three cover crop management systems. The multivariate analysis performed pointed to those seed species that have a major influence on the aboveground flora communities of each of the three agricultural systems. The seed bank was clearly impoverished in terms of both abundance and species richness after the long‐term conventional tillage practices. We conclude that the intensive long‐term conventional tillage dramatically reduces weed communities in olive orchards and the subsequent ecosystem services provided by them. [ABSTRACT FROM AUTHOR]

Agricultural intensification has greatly affected biodiversity in recent decades. One common and recent transformation that has taken place in Mediterranean countries is olive grove intensification, although its effects on biodiversity have rarely been studied.In the present study, we investigated the effect of soil management practices, with versus without soil cover crops, on the arthropod abundance, richness, diversity and species composition in Andalusia olive groves, South Spain.The results obtained show that these soil cover crops positively affect the diversity of arthropods, along with other variables such as the diversity of the plant community and Shannon index of the landscape. By contrast, the number of arthropods was higher in olive groves with bare ground as a result of the abundance of two families (Entomobryidae and Aeolothripidae), which comprised more than 50% of all the individuals collected.Rank abundance diagrams and multivariate analyses showed differences between the two types of soil management systems with respect to the composition of families.In conclusion, soil cover crops strongly improve the diversity of arthropods in olive orchards, which helps to maintain biodiversity in these intensive agroecosystems at the same time as improving other ecosystems services, such as soil fertility and the prevention of soil erosion. [ABSTRACT FROM AUTHOR]

Terra Nova, 22, 172–179, 2010 Giant load-type seismites, uncommon in the geological record, are described in Plio-Pleistocene lacustrine deposits of the Baza Basin (Betic Cordillera, S Iberia). Deformed beds of the marginal lacustrine and distal alluvial facies of the Baza palaeo-lake can be traced continuously for several kilometres. Soft-sediment deformation is represented by load-type structures of large dimensions (pillows around 4 m in width and 2 m in height). Three-dimensional exposures show ellipsoidal pillows separated by fluidized channels without any preferred orientation. The final size of these load-type seismites is strongly influenced by sedimentary factors such as the presence of a reverse density gradient in sediments and the bed thickness. The giant seismites of the Baza basin are located in a region, which is unlikely to have been subjected to high magnitude earthquakes (maximum around 7.0). Therefore, magnitude is not the main factor that controls the size of these load-type structures. [ABSTRACT FROM AUTHOR]

Knowledge of intrinsic and extrinsic factors associated with survival rates and the underlying causes of mortality is essential to understand both population dynamics and the causes of population declines. We studied the influence of habitat variables and body condition on survival of 151 radio-tracked Red-legged Partridges Alectoris rufa in four areas of Spain, representing a gradient from natural unmanaged areas to highly managed areas. We examined the effects of differences in game management practices, and seasonal and geographical variations in survival and causes of mortality over 4 years, from 1999 to 2002. Monthly survival rate was consistently over 90% for both sexes in the natural area. However, in two areas managed intensively for both hunting and agriculture, survival was low during the hunting period (72% for females and 79% for males), high during the breeding period for males (99%), and intermediate for females (89%) due mainly to diseases. Hunting was the main cause of Red-legged Partridge mortality in both hunting areas where driven partridge shooting was performed, affecting 50% of radio-tagged individuals, and was the main cause of mortality over all areas during both breeding and hunting periods. Disease was the next most common cause of mortality in managed areas, affecting mostly females during the breeding period, whereas predation was the main cause of mortality in unmanaged populations. Finally, we compared the habitat associations and body condition of living and dead individuals with varying causes of mortality. In general, high survival rates were associated with diverse vegetation, habitat edges and a good body condition index. Habitat diversity and a high edge index were also negatively associated with mortality due to predation and diseases. On the other hand, hunting mortality decreased with the proportion of scrubland and increased with the proportion of agricultural land. These results suggest that preventing declines of wild Red-legged Partridge populations might best be achieved by increasing landscape complexity and connectivity, and promoting game management practices to limit both partridge bags and long-term densities. [ABSTRACT FROM AUTHOR]