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One of the main problems in close-to-nature management of high forests is linked to the ecological and economic aspects of salvage logging. This research involved analysing soil disturbance from salvage logging in four mountain forests, managed with close-to-nature silviculture: the Hyrcanian forest (three forest compartments in Iran), using extraction by skidder, and the Camaldoli forest (one parcel in Italy), using extraction by tractor. The point transect method was used for assessing soil disturbance and also included further measurements of ruts' size and selected physical soil parameters on skid trails after operation. After a windstorm, more than 94% and 17% of the area were undisturbed in the Hyrcanian and Camaldoli forests, respectively. Bulk density, penetration resistance, and pH did not show any significant differences with their average values specifically between disturbed and undisturbed soil after a windstorm. Related only to the effect of salvage logging, more than 80% of the area was undisturbed. The results were significantly lower in terms of the average values of soil variables such as bulk density, penetration resistance, and total porosity in disturbed soil than in undisturbed soil. For all the sites that were studied, bulk density and penetration resistance increased with the increasing number of machines that passes, while total porosity decreased. The results showed significant positive correlations between bulk density and penetration resistance, bulk density and pH value, and total porosity and pH value and significant negative correlations between bulk density and total porosity and penetration resistance and total porosity. The results indicated that the point transect method of assessing soil disturbance provides a rapid assessment of soil conditions for monitoring soil disturbance after salvage logging. Our results also indicated that to reduce impacts to soil during salvage logging, if the volume of windthrow timber is low, salvage logging is not always necessary because of the broad ecological importance as well as the economic aspects of dead wood in forest ecosystems. [ABSTRACT FROM AUTHOR]

In central Italy, there are extensive European black pine (Pinus nigra Arn.) plantations which range from 30 to 60 years of age and where no thinning operations have been made. The main purpose of this study was to provide a comparative analysis of two cable yarder technologies (Maxwald, mobile pulley carriage and Savall, semi-automatic carriage), in terms of fuelwood production and cost, from the first thinning of a 33 year old plantation in slope areas of these plantations. The results showed that fuelwood production was cost-effective in both systems (Savall by 15.1 and Maxwald by 14.8 € m−3), although the productivity of the Savall system was higher than the Maxwald system (6.1 vs. 5.7 m3 h−1). The respect amounts of productivity have the potential to increase by 27% for the Savall yarder and 25% for the Maxwald yarder upon condition that the delay times are reduced to minimum level by proper training of workers, by a better organization, and planning of operations. The total effective CO2 emission by the Savall yarder was lower than the Maxwald yarder (1735 vs. 1772 g m−3). A sustainable production of fuelwood that is economically advantageous and environmentally sound in these plantations can be realized through an appropriate mechanization level and constant interaction with the silvicultural planning. This must be completed with adequate and efficient worker training. [ABSTRACT FROM AUTHOR]

There are many data values describing deadwood in primary forests, however, there is much less information concerning managed forests, particularly in the Mediterranean area. Whole non-living woody biomass (deadwood) is the main component of forest types that plays a vital role in improving and maintaining biodiversity. The dynamics of deadwood and CO2 sequestration by deadwood were examined in three Mediterranean lowland forests: pine forest Pinus pinea L.), evergreen oak forest (Quercus ilex and Quercus suber L.), and deciduous oak forest (Quercus cerris L.). The aim of this study was to carry out a quantitative and qualitative evaluation of the deadwood to gather useful information for the Mediterranean forest management, and to provide some useful data that can be integrated into the methods of estimation for carbon stored in dead components of Mediterranean forest types. The investigations focused on the characterization of the deadwood, to determine which traits are dominant and their potentially functionality within the forest type. Results indicated the deciduous oak type had the highest amount of stand volume (379 m3/ha), deadwood volume (161.8 m3/ha), and C storage (31.43 t/ha). The major component of dead wood was the standing dead trees or snags. There was a higher volume of deadwood in the deciduous oak forest than in the pine and evergreen oak forests. In addition, the deciduous oak forest had a higher snag creation index, a higher fallen log creation index, and a higher past management index compared to pine and evergreen oak forest types. Deadwood volume increased as the decay class in the deciduous oak forest increased, while this trend decreased in the evergreen oak and pine forests. The amount of deadwood was affected by the forest type and forest management regime. Dynamic and past management of deadwood indices indicated that their structure was still in the initial phase of creation and decay in the pine and evergreen oak forests. A comparison with other studies on similar forest types brought out that the variation range of the main parameters for the management of deadwood fell within the variation of the parameters studied. However, the values of these parameters cover a broad range. The population of each forest type is extremely sensitive to the different evolutionary periods of the forest dynamics. [ABSTRACT FROM AUTHOR]