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Planting new forests has received scientific and political attention as a measure to mitigate climate change. Large, new forests have been planted in places like China and Ethiopia and, over time, a billion hectares could become available globally for planting new forests. Sustainable management of forests, which are available to wood production, has received less attention despite these forests covering at least two billion hectares globally. Better management of existing forests would improve forest growth and help mitigate climate change by increasing the forest carbon (C) stock, by storing C in forest products, and by generating wood-based materials substituting fossil C based materials or other CO2-emission-intensive materials. Some published research assumes a trade-off between the timber harvested from existing forests and the stock of C in those forest ecosystems, asserting that both cannot increase simultaneously. We tested this assumption using the uniquely detailed forest inventory data available from Finland, Norway and Sweden, hereafter denoted northern Europe. We focused on the period 1960 - 2017, that saw little change in the total area covered by forests in northern Europe. At the start of the period, rotational forestry practices began to diffuse, eventually replacing selective felling management systems as the most common management practice. Looking at data over the period we find that despite significant increases in timber and pulp wood harvests, the growth of the forest C stock accelerated. Over the study period, the C stock of the forest ecosystems in northern Europe increased by nearly 70%, while annual timber harvests increased at the about 40% over the same period. This increase in the forest C stock was close to on par with the CO2-emissions from the region (other greenhouse gases not included). Our results suggest that the important effects of management on forest growth allows the forest C stock and timber harvests to increase simultaneously. The development in northern Europe raises the question of how better forest management can improve forest growth elsewhere around the globe while at the same time protecting biodiversity and preserving landscapes.

Species rich woodland communities play an important role in ecosystem functioning at local, regional and global scale. With ongoing climate change and an ever-increasing human world population we certainly cannot take high species diversity for granted. In fact species diversity is a precious and threatened commodity that requires monitoring and conservation. China has a wealth of natural woodlands with high species diversity that stretch over several climate zones and even in the temperate zone tree diversity is considerable in this country. For monitoring species diversity it is crucial to rely on meaningful summary characteristics that offer sufficient information to make correct decisions in conservation. We analysed large, fully mapped plots from ten species-rich temperate forest sites with the new species segregation function as a significantly more meaningful extension of the traditional spatial species mingling index. The new characteristic is a function of distance and we defined a number of auxiliary measures describing its shape for a more effective analysis of spatial species diversity. We could show that these auxiliary characteristics helped to classify species-rich forests as part of a cluster analysis, which supports the view that the species segregation function provides high quality information. We also successfully applied non-parametric modelling through spatial reconstruction for testing the contribution of the species segregation function to a synthesis of observed spatial species diversity patterns. The results demonstrated that the new characteristic described the complex diversity patterns well and has the potential of being a robust and effective characteristic in monitoring species-rich woodland communities.

The setting (distance between mantle and concave ring) of the Hydrocone cone crusher is altered, even with the crusher operating at full load, by lifting or lowering the mantle by means of a hydraulic piston (Hydroset). Modern developments in the field of electronics and microcomputers have made it possible to design a small, reliable and very sophisticated system for automatic regulation of the setting of a Hydrocone crusher. The system monitors energy consumption, crushing force and setting and continuously adapts the crusher to even small variations in the feed and/or operating conditions. This technology has expanded the range of applications that can be successfully solved with cone crushers. In the paper we will give a general description of modern cone crusher technology and also give some examples of new possible applications. Fine crushing in closed circuit with a screen can, thanks to automation and carefully designed crushing chambers, compete with rod mills. Products smaller than 3 mm are common. Another example is the crushing of a gold ore to −10 mm, in open circuit, with a Hydrocone crusher. The automation system ensures that the crusher runs at the smallest possible setting and thus ensures that the correct discharge is produced. In some applications it is interesting to operate cone crushers in a wet process. About 20 years ago, Allis Mineral Systems installed the first Hydrocones with water injected together with the feed. These crushers are still in operation and we will present our experiences. Small flexible cone crushers with computer control can be used to create more cost efficient ore crushing plants than the conventional installations with few large machines. The “crushing cassette” idea is presented.