Important land cover changes were documented in several areas of the Mediterranean basin with associated hydrological effects. This paper aims at contributing to the characterization of land use changes and vegetation cover in a basin representative of the Mediterranean mountain range, and quantifying the impact of those changes on lateral and vertical flows (discharge and evapotranspiration, respectively). For this purpose, a series of precipitation data and some components of the hydrological cycle were analyzed: streamflow-runoff in two periods (1933-1948 and 1996-2012). In addition, a spatial analysis of land use changes was carried out; this information was used for the spatial analysis of the curve number and evapotranspiration. Main results indicated that precipitation had not changed significantly between both periods, while streamflow declined by a 43 %, together with the loss of 63 % of agricultural areas that were replaced by shrubland and forest. Evapotranspiration increased in 57 % of the drainage area, with an average increase of 20 mm year-1. In general, the partition of rainfall was readjusted due to the recovery and changes of the natural vegetation cover, facilitating a redistribution of water within the hydrological cycle. As a result, the observed increase of vertical fluxes and the decrease of horizontal ones could potentially affect the hydrological resources of the area.
Ring shake is a widespread phenomenon affecting a great number of species of both softwood and hardwood and is found in trees grown in temperate and tropical climates. Chestnut (Castanea sativa Mill.) represents one of the most important hardwood timbers that is very often affected by ring shake. This defect seems to be the only real limit to the spread and use of chestnut wood worldwide on a scale closer to the availability of this wood. The aim of this study was to examine the potential of tomographic measurement as a non-destructive method for predicting the possibility of the presence of ring shake in standing chestnut trees. For this reason, the experiments were carried out in a chestnut coppice stand where one hundred chestnut standards were monitored using an acoustic tomographic device, and subsequently harvested by a local company and cross-sectioned corresponding to the acoustic tests. This work proposed an applied approach to predicting and determining wood quality (sound wood vs. defective wood) from tomographic data. The model, based on a non-linear approach, showed that sonic tomography can identify ring shake in a tree trunk without affecting its biological activity, overcoming the difficulties of predicting ring shake using only visual inspection.
Forwarding technology is well established in use around the world but, at the same time, forwarders are expensive machines that require a good planning to ensure the sustainability of operations. In addition, forwarder market is characterized by a limited pool of customers, therefore innovation attempts may be limited compared to other product development industries. Since the steps towards a full automation of operations are still at their beginning, improvements of forwarder machines may rest in developing and integrating components that could contribute to an increased effectiveness. To respond to such challenges, the Forwarder2020 project developed innovative components that were integrated in a number of forwarder prototypes based on a market pull approach that resulted in a flexible adaptation to customer requirements and work environments. Since one of the typical work environments was that of low access forests, some components (i.e. suspended cabin and transmission system) were engineered to enable faster and safer operations and to economize fuel. As a common validation step is that of bringing field evidence on the performance improvement, this study evaluated the operational speed, productivity and fuel consumption of a forwarder prototype in conditions of a steep-terrain low-access forest. The main findings were very promising as the prototype was able to operate at significantly increased speeds and the fuel savings were evident. For an average forwarding distance of about 1.5 km, net productivity and efficiency rates were estimated at 14.4 m3/h and 0.07 h/m3, respectively. They were related to the availability of wood, and further improvement of such figures is possible by a better organization of tree felling and processing. Operational speed was affected by the condition of skid roads used for forwarding, which were harsh. During the transportation tasks developed on roads typical for forwarding, the machine was able to sustain average speeds estimated at 8 km/h. As a matter of fact, in such tasks, the dominant operational speed (almost in 100% of the cases) was higher than 5 km/h irrespective of the road condition. Hourly fuel consumption was estimated based on the time in which the engine was working and it amounted to 17.1 l/h. More importantly, by considering the forwarded payload in terms of volume and mass, the unit fuel consumption was estimated to be 1.25 l/m3 and 1.47 l/t, respectively. These results bring evidence on the performance improvement by modular innovation. In fact, such solutions could answer the challenges related to the sustainability of forest operations in low access forests.
In recent decades, the use of forwarders in agroforestry systems has been increasing. In agroforestry systems, the possibility to use these machines in various operational contexts allows the reduction of hourly costs and favors its use also in small enterprises. In Europe, agroforestry or farm forestry represents an important resource that offers alternative and more sustainable land uses in agricultural or forestry areas. By covering large areas, fruit orchards represent an important source of income, but they require annual pruning which leaves abundant residues on the ground. And when fruit production declines, the trees are dismantled to make room for new ones. This study evaluated the performance of biomass recovery from dismantled apple orchards using a HSM 208 F forwarder. Time studies were implemented to estimate the productivity and fuel consumption of forwarding operations. Data was collected by means of a GPS unit, a video camera and an electric fuel pump, and 30 work cycles divided into elemental tasks were monitored. Models for time consumption and productivity as a function of extraction distance were developed by means of least-square simple regression, at different scales needed to characterize the forwarding operations. The average forwarding distance was of ca. 830 m and the net and gross forwarding production rates were of 21.79 and 15.35 loose m3 h − 1 (volume of woodchips produced), respectively. The study provides reference data for forwarding operations and demonstrates the successful use of forestry machines in the agricultural sector.
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