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The transition to a low carbon future is starting to affect landscapes around the world. In order for this landscape transformation to be sustainable, renewable energy technologies should not cause critical trade-offs between the provision of energy and that of other ecosystem services such as food production. This literature review advances the body of knowledge on sustainable energy transition with special focus on ecosystem services-based approaches and methods. Two key issues emerge from this review: only one sixth of the published applications on the relation between renewable energy and landscape make use of the ecosystem service framework. Secondly, the applications that do address ecosystem services for landscape planning and design lack efficient methods and spatial reference systems that accommodate both cultural and regulating ecosystem services. Future research efforts should be directed to further advancing the spatial reference systems, the use of participatory mapping and landscape visualizations tools for cultural ecosystem services and the elaboration of landscape design principles.

A commercial drum chipper was fed alternately and piecewise with poplar stems and poplar tops, in order to determine the effect of piece size and tree part on machine performance. Chipping stems required most of the available power (231 kW) delivered by the tractor, whereas chipping tops took about half that much. However, productivity was twice as high with stems, compared to tops (i.e. 25 and 11 t h-1 of oven dry wood, respectively). As a consequence, specific fuel consumption per unit product was 15% lower with stems, compared to tops - i.e. 0.61 and 0.72 L m-3, respectively. Mean feeding speed was 0.37 m s-1 for stems and 0.41 m s-1 for tops, but the difference was not significant (p = 0.1677). Productivity and fuel consumption were strongly related to piece size, but tree part had its own additional effect, independent from size and possibly related to form. When chipping tops it is advisable to feed more pieces at a time, in order to partly compensate for the effect of piece size. Operators expecting to chip primarily small-size materials may acquire special chipper versions with wider drums and additional side rollers, for smoother mass feeding. oThe same chipper was tested with poplar stems and tops.oChipping stems resulted in higher productivity and lower fuel consumption.oChipping stems required most of the available tractor power.oChip particle size distribution was about the same for both feedstocks. © 2013 Elsevier Ltd.

The Indian Ocean Experiment (INDOEX) was an international, multiplatform field campaign to measure long-range transport of air pollution from South and Southeast Asia toward the Indian Ocean during the dry monsoon season in January to March 1999. Surprisingly high pollution levels were observed over the entire northern Indian Ocean toward the Intertropical Convergence Zone at about 6°S. We show that agricultural burning and especially biofuel use enhance carbon monoxide concentrations. Fossil fuel combustion and biomass burning cause a high aerosol loading. The growing pollution in this region gives rise to extensive air quality degradation with local, regional, and global implications, including a reduction of the oxidizing power of the atmosphere.

Industrial poplar plantations represent a strategic source of wood products for many countries. Harvested after 10 to 30 years, they yield about 200 t ha-1 of timber and 100 t ha-1 industrial wood. The latter is obtained from poplar tops, which can be converted into chips, or a mix of pulpwood and chips. The study compared four options to process poplar tops. Alternatives derived from the intersection of two product strategies (pulpwood and chips, or chips only) with two pulpwood processing methods (manual or mechanized). Both mechanization and simplification (only one product) succeeded in reducing production cost, but the former had a stronger effect. The tests demonstrated that all options were cost-effective and could return some profits. However, the exclusive production of chips offered lower profits, compared to an articulate product strategy aimed at maximising value recovery. In the case of Italian poplar plantations, the price difference between pulp and chips is generally larger than the cost reduction obtained with integral chipping. Similar conclusions were reached by other authors working with spruce and beech in Central Europe. Of course, this is only true for the current price levels of pulpwood and chips: results may change, if this price balance will be altered by the growing demand for biomass fuel.

Biomass to be composted is often very heterogeneous and collection of representative samples for determination of compost properties is therefore difficult, especially under full-scale conditions. During full-scale composting different biomasses in the amount of 10–100 tons are mixed, yielding a very heterogeneous mixture. Final sample size for compost property determination is usually a few grams compared with compost pile masses of hundreds of tons. Desired sample particle size is about 1 mm, while compost particle size ranges from 5 to 50 cm. This study focuses on the development of a strategy for sampling under full-scale conditions for minimum measurement uncertainty based on selected material properties. Optimization was conducted considering multiple parameters, such as number of pile turnings before sampling, number of samples collected, sample mass, sample homogenization, particle size reduction and number of replicate measurements. Measurement uncertainty was evaluated using water content, inorganic matter content and nutrient (nitrogen, phosphorus) content. For each parameter measurement variability was determined as a function of sampling strategy and used to identify optimal sampling strategy.

The authors tested a 409kW forager turned into an industrial chipper through a special conversion kit. Conversion was temporary, and the forager could be returned to its original occupation with one day of work. The converted forager proved as effective as a dedicated chipper of the same power. Net chipping productivity varied between 25 and 33greenth-1. Productivity was highest with poplar tops and lowest with pine tops. Fuel consumption ranged from 1.6 to 1.8lgreent-1. Fuel consumption did not change with tree species, but increased significantly with knife wear. Temporary conversion allowed a better depreciation of the invested capital and resulted in a 25% reduction of unit chipping cost. The converted forager proved an ideal solution wherever the production of wood chips was a complementary business within the scope of a larger agricultural economy. In technical terms, this machine offered the combined advantages of road-capability and good off-road mobility, allowing low-cost independent relocation and effective in-field chipping. © 2013 Elsevier Ltd.

The growing interest in forest biomass has made chipping increasingly popular all across Europe. Many operators have equipped for the purpose, but the large variety of working conditions found in the European forests makes it difficult to correctly estimate the productivity of each specific operation, leading to uncertainty in crucial decisions, such as: operation scheduling, price setting, machinery selection and acquisition. In 2001, the Italian National Council for Research (CNR) and the University of California (UC) developed a spreadsheet freeware capable of returning reliable estimates of chipping productivity and cost, on the basis of user-defined input data. The model is still available from the CNR website and is the object of frequent downloading and inquiries. Such model contains a set of predictive equations derived from the results of 102 field trials, conducted with 30 different machines, under a range of working conditions. In order to facilitate comparison with other estimates and to achieve methodological transparency, the equations are assembled into a simple Microsoft Excel workbook, and the costs are calculated with standard costing methods currently used in Forest and Agricultural Engineering. Since then CNR has continued to work on the subject, with the goal of updating and refining the model. Such work has included 45 validation tests and a separate study on the delay (idle) time typical for different chipping operation layouts. The study was concluded in 2009 and confirms that the model developed by CNR can provide reliable estimates of chipper productivity under a range of operational conditions. Authors believe that such a model can assist European foresters in keeping ahead with the growing biomass sector, thus helping them to seize an important business opportunity.

The Authors surveyed 6 industrial chipping operations for a whole work year, collecting data about machine usage, product output, fuel consumption and chipper knife wear. Despite the challenging work conditions offered by mountain operations, industrial chipping contractors manage to achieve a high machine use, ranging from 500 to over 2,500 h year(-1). Product output varies between 18,000 and over 120,000 m(3) loose chips per year. In order to acquire enough jobs, operators may travel between 1,500 to over 20,000 km in a year. Industrial chipping contractors adopt different operational strategies to achieve their production targets, and they equip accordingly. Some operators prefer to tap smaller local areas and opt for smaller tractor-powered chippers, which are less powerful and productive than larger independent-engine units, but cheaper and capable of negotiating low-standard forest roads. Others prefer to explore larger areas and achieve higher product outputs, and they opt for larger independent-engine chippers, often mounted on trucks. Long term productivity varies with machine type: tractor-powered units produce between 40 and 50 m3 loose chips per hour, whereas larger independent-engine chippers produce between 60 and 90 m3 loose chips per hour. Specific fuel consumption is about 0.5 L diesel per m3 loose chips, regardless of chipper type. A sharp knife set can process between 200 and 1,500 m3 loose chips before getting dull. Disposable knives last longer and are cheaper to manage than standard re-usable knives. (C) 2014 Elsevier Ltd. All rights reserved.