Current UK guidance suggests that a ‘rootable’ soil profile of at least 1.0 m depth should be sufficient to allow adequate rooting of the majority of tree species in a range of soil types and climatic conditions [Arboricultural Journal (1995) vol. 19, 19–27]. However, there is some uncertainty as to what constitutes a loosened soil profile in terms of penetration resistance. In this study the root development of Italian alder, Japanese larch, Corsican pine and birch was assessed after 5 years of tree growth. These data were compared to penetration resistance measured using both a cone penetrometer and a ‘lifting driving tool’ (dropping weight penetrometer). Tree root number and percentage were significantly reduced by increasing soil penetration resistance measured with both the cone penetrometer (P < 0.050) and the ‘lifting driving tool’ (P = 0.011 and 0.008 respectively). The vast majority of roots were recorded in soils with a penetration resistance of less than 3 MPa (90.7%) with a significant amount in the less than 2 MPa class (70.2%). Root development of Italian alder, Japanese larch and birch all showed a similar pattern, but Corsican pine appeared to be capable of rooting into more compact soils. The ‘lifting driving tool’ can be used as an alternative measure of soil penetration resistance. This equipment is more cost effective, easier to use and capable of measurements at a greater depth than the cone penetrometer. The majority of Japanese larch and birch roots (84.3%) were recorded in soils where it took less than 15 impacts to penetrate one 10 cm soil depth increment. The modelled data also suggest that a penetration resistance of 2 and 2.5 MPa relates to 10 and 15 impacts respectively.
The huemul Hippocamelus bisulcus is an endangered species of deer occupying temperate woodland habitats in the Andes of southern Chile and Argentina. Continuing declines due to a combination of hunting and habitat loss have created a need for more conservation measures. However, current information on ranging behaviour, dispersal and seasonal movements is very limited. Three sites were therefore selected in Ayse´n, Chilean Patagonia, to study the movements and habitat associations of huemul. Although seasonal migrations in elevation had been reported previously for the species, we found the extent of seasonal movement limited, much less than that reported for other deer species in mountainous environments. Huemul selected mid-slope elevations, and the winter ranges of most animals overlapped summer ranges. The extent of the seasonal movements that were undertaken were, however, the greatest at the highest site and insignificant at the lowest site. Previously published information shows that habitats used by huemul follow a latitudinal gradient in elevation (reducing c. 100 m 1S À1 in latitude), and our results suggest that seasonal movements are likely to be greater in sites above this line. The mean range size differed between sites, ranging from 357 to 656 ha (mean 444 ha; median 506 ha). These estimates excluded longdistance (45 km) movements, which were infrequent.
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