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Due to the enhanced demands for woody biomass, it is increasingly relevant to assess possibilities to harvest forest residues in addition to logs. Here, eight strategies for whole-tree harvesting from clearcuts and early thinnings of pine (Pinus nigra Arnold) stands in northern Belgium are evaluated. A detailed cost analysis using the machine-rate method was conducted along with scenario and sensitivity analyses of the variables affecting the harvesting cost. On average, we found much higher revenue for logs than for wood chips from forest residues. In clearcuts, a mobile chipper was more profitable than a roadside chipper. On the other hand, the harvesting cost of logs was higher for early thinnings than for clearcuts. However, the revenue remained higher than for chips, making the separate harvesting of logs and chips more cost effective than chipping whole trees. In the latter case, an excavator, a forwarder, and a roadside chipper were more cost effective than a harvester, a tractor with trailer, and a mobile chipper, respectively. Harvest of additional woody biomass required limited energy input compared with processing and intercontinental transportation of wood pellets. However, at present, we find very small profits from local additional biomass harvests. The low and fragmented forest cover and important sustainability issues further impede the development of a viable production sector in this region. Key words: whole-tree harvesting, woody biomass, harvest strategies, economic analysis, energy balance. Resume: Etant donne la demande accrue de biomasse ligneuse, il est de plus en plus pertinent d'evaluer la possibility d'exploiter les residus forestiers en plus des billes. Huit strategies d'exploitation par arbres entiers appliquees lors de coupes a blanc et d'eclaircies precoces dans des peuplements de pin (Pinus nigra Arnold) situes dans le nord de la Belgique ont ete evaluees. Une analyse de cout detaillee par la methode des taux de machinerie a ete realisee ainsi que des analyses de scenarios et de sensibilite des variables qui influencent le cout d'exploitation. En moyenne, nous avons obtenu un revenu beaucoup plus eleve pour les billes que pour les copeaux de bois produits a partir des residus forestiers. Dans les coupes a blanc, une dechiqueteuse mobile etait plus rentable qu'une dechiqueteuse en bordure de route. Par contre, dans les eclaircies precoces le cout d'exploitation des billes etait plus eleve que dans les coupes a blanc. Cependant, les revenus sont demeures plus eleves que pour les copeaux de telle sorte qu'il etait plus rentable d'exploiter les billes et les copeaux separement que de dechiqueter des arbres entiers. Dans le dernier cas, une excavatrice, un porteur et une dechiqueteuse en bordure de route etaient plus rentables qu'une machine multifonctionnelle, un tracteur avec une remorque et une dechiqueteuse mobile. La recolte de biomasse ligneuse additionnelle a necessite un apport limite d'energie comparativement a la fabrication et au transport intercontinental de granule de bois. Cependant, nous constatons que les profits tires de la recolte locale de biomasse additionnelle sont actuellement tres faibles. Le couvert forestier clairseme et fragmente ainsi que les questions de durabilite constituent une entrave supplementaire au developpement d'un secteur de production viable dans cette region. [Traduit par la Redaction] Mots-cles: exploitation par arbres entiers, biomasse ligneuse, strategies d'exploitation, analyse economique, bilan energetique., Introduction The use of woody biomass for bioenergy has increased by almost 80% in the 27 European Union (EU) member states between 1990 and 2008 (Eurostat 2011). Moreover, the demand [...]

Pine plantations established on former heathland are common throughout Western Europe and North America. Such areas can continue to support high biodiversity values of the former heathlands in the more open areas, while simultaneously delivering ecosystem services such as wood production and recreation in the forested areas. Spatially optimizing wood harvest and recreation without threatening the biodiversity values, however, is challenging. Demand for woody biomass is increasing but other pressures on biodiversity including climate change, habitat fragmentation and air pollution are intensifying too. Strategies to spatially optimize different ecosystem services with biodiversity conservation are still underexplored in the research literature. Here we explore optimization scenarios for advancing ecosystem stewardship in a pine plantation in Belgium. Point observations of seven key indicator species were used to estimate habitat suitability using generalized linear models. Based on the habitat suitability and species' characteristics, the spatially-explicit conservation value of different forested and open patches was determined with the help of a spatially-explicit conservation planning tool. Recreational pressure was quantified by interviewing forest managers and with automated trail counters. The impact of wood production and recreation on the conservation of the indicator species was evaluated. We found trade-offs between biodiversity conservation and both wood production and recreation, but were able to present a final scenario that combines biodiversity conservation with a restricted impact on both services. This case study illustrates that innovative forest management planning can achieve better integration of the delivery of different forest ecosystem services such as wood production and recreation with biodiversity conservation. [ABSTRACT FROM AUTHOR]

Waste policy is increasingly moving on from the 'prevention of waste' to a 'sustainable materials policy' focused agenda recognising individual wastes as a resource. In order to comparatively analyse policy developments in enhanced waste management, three case studies were selected; San Francisco's Zero Waste Program, Flanders's Sustainable Materials Management Initiative and Japan's Sound Material-Cycle Society Plan. These case studies were chosen as an opportunity to investigate the variety of leading approaches, governance structures, and enhanced waste policy outcomes, emerging globally. This paper concludes that the current transitional state of waste management across the world, is only in the first leg of the journey towards Circular Economy closed loop production models of waste as a resource material. It is suggested that further development in government policy, planning and behaviour change is required. A focus on material policy and incorporating multiple front runners across industry and knowledge institutions are offered as potential directions in the movement away from end-pipe land-fill solutions., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Conjugated linoleic acid (CLA) and conjugated linolenic acid (CLNA) isomers are present in foods derived from ruminants as a result of the respective linoleic acid (LA) and α-linolenic acid (LNA) metabolism by ruminal microorganisms and in animals' tissues. CLA and CLNA have isomer-specific, health-promoting properties, including anticarcinogenic, antiatherogenic, anti-inflammatory, and antidiabetic activity, as well as the ability to reduce body fat. Besides ruminal microorganisms, such as Butyrivibrio fibrisolvens, many food-grade bacteria, such as bifidobacteria, lactic acid bacteria (LAB), and propionibacteria, are able to convert LA and LNA to CLA and CLNA, respectively. Linoleate isomerase activity, responsible for this conversion, is strain-dependent and probably related to the ability of the producer strain to tolerate the toxic effects of LA and LNA. Since natural concentrations of CLA and CLNA in ruminal food products are relatively low to exert their health benefits, food-grade bacteria with linoleate isomerase activity could be used as starter or adjunct cultures to develop functional fermented dairy and meat products with increased levels of CLA and CLNA or included in fermented products as probiotic cultures. However, results obtained so far are below expectations due to technological bottlenecks. More research is needed to assess if bacterial production kinetics can be increased and can match food processing requirements.

There is great interest in conjugated linoleic acid (CLA) and conjugated linolenic acid (CLNA) isomers because of their supposed health-promoting properties. Therefore, the differences in production kinetics of CLA and CLNA isomers from linoleic acid (LA) and α-linolenic acid (α-LNA), respectively, by bifidobacteria were investigated. Laboratory fermentations, supplemented with LA or α-LNA in the fermentation medium, were performed with Bifidobacterium bifidum LMG 10645, Bifidobacterium breve LMG 11040, B. breve LMG 11084, B. breve LMG 11613, B. breve LMG 13194, and Bifidobacterium pseudolongum subsp. pseudolongum LMG 11595. Conversion of LA and α-LNA to CLA and CLNA isomers, respectively, started immediately upon addition of the substrate fatty acids. During the active growth phase, the c9, t11-CLA isomer and the putative c9, t11, c15-CLNA isomer were formed. Further fermentation resulted in a reduction in the concentration of c9, t11-CLA and c9, t11, c15-CLNA and the subsequent production of the t9, t11-CLA isomer and the putative t9, t11, c15-CLNA isomer, respectively. Modelling of the growth and metabolite data indicated differences in production kinetics among the strains. Some strains displayed a high specific conversion of LA and α-LNA despite poor growth, whereas other strains grew well but displayed lower conversion. Production of specific CLA and CLNA isomers by bifidobacteria holds potential for the production of functional foods and could contribute to their probiotic properties., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Conjugated linoleic acid (CLA) and conjugated linolenic acid (CLNA) isomers have attracted great interest because of their potential health benefits. Formation of CLA and CLNA takes place in the rumen during biohydrogenation. Several studies have indicated that certain types of intestinal bacteria, including bifidobacteria, are able to convert linoleic acid (LA) to CLA. The role of intestinal bacteria in the formation of CLNA isomers is largely unknown. In the present study, a screening of 36 different Bifidobacterium strains for their ability to produce CLA and CLNA from free LA and alpha-linolenic acid (LNA), respectively, was performed. The strains were grown in MRS broth, to which LA or LNA (0.5 mg ml(-1)) were added after 7 h of bacterial growth. Cultures were further incubated at 37 degrees C for 72 h. Six strains (four Bifidobacterium breve strains, a Bifidobacterium bifidum strain and a Bifidobacterium pseudolongum strain) were able to produce different CLA and CLNA isomers. Conversion percentages varied from 19.5% to 53.5% for CLA production and from 55.6% to 78.4% for CLNA production among these strains. The CLA isomers produced were further identified with Ag(+)-HPLC. LA was mainly converted to t9t11-CLA and c9t11-CLA. The main CLNA isomers were identified with GC-MS as c9t11c15-CLNA and t9t11c15-CLNA.

Although several studies have suggested that behavioural measures may be more comprehensive than other biomarkers for indicating an organism's health or welfare, this has rarely been investigated in free-living terrestrial vertebrates. Here we examine the expression of dawn singing behaviour in a free-living small songbird in relation to environmental pollution. We compared the singing behaviour of male great tits Parus major inhabiting an area extremely polluted with heavy metals with that of males inhabiting areas of low(er) pollution (at 4 and 20 km distance from the pollution source). Males at the most polluted site had a significantly smaller repertoire size than males at the two other sites. They also produced a significantly lower total amount of song during the dawn chorus than the males at a distance of 4 km from the pollution source. Our results, although non-experimental and obtained in field conditions, strongly suggest that heavy metal pollution might affect the expression of singing behaviour. Taking into account that previous studies were not able to detect clear, straightforward differences between the health of great tits at the most polluted site and at 4 km distance from the pollution source, our results suggest that the singing behaviour of great tits may be a useful indicator of environmental stress at the population level.