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Knowledge of the patterns in the degradation of cellulose and lignin in decaying logs under different climatic conditions is necessary to understand the carbon cycling in forest ecosystems since cellulose and lignin are the dominant carbon fractions in decaying logs. However, the effects of the environmental heterogeneity by variation in canopy cover on the degradation of cellulose and lignin in decaying logs remain unknown. To evaluate the effect of forest gaps, we measured the concentration and mass loss of cellulose and lignin in experimentally exposed decaying logs in gaps, at the edge of gaps, and under the closed canopy during a four-year in situ log incubation experiment in a subalpine Minjiang fir (Abies faxoniana) forest on the eastern Qinghai-Tibet Plateau, China. We found the lowest cellulose concentration in gaps for all wood tissues, while we observed the opposite for lignin except for bark. Based on the linear relationship between cellulose and lignin concentrations, the rate of lignin enrichment in bark and heartwood was slowest in gaps and fastest under closed canopy, while in sapwood gaps had almost no influence. The mass loss of cellulose was highest in gaps for all wood tissues in any decay classes. The gap effect on lignin mass loss in decaying logs showed high variability with wood tissues and decay classes. Our results show that forest gaps accelerate the degradation of cellulose and lignin during the decomposition of logs by increasing cellulose mass loss and slowing lignin enrichment. The observed gap effects were mediated by wood tissues but not by decay classes. [ABSTRACT FROM AUTHOR]

Modelling and simulation of mixed-traffic zones is an essential tool for transportation planners to assess safety, efficiency, and human-friendliness of future urban areas. This paper addresses the calibration and transferability of existing shared space models for pedestrians and cars. Specifically, our first contribution is enhancing the Game-Theoretic Social Force Model (GSFM) by a generic methodology for largely automated model calibration. The second contribution is an investigation into the transferability of shared space models. We define criteria for model transferability and present a case study, in which we evaluate transferability of the model we constructed based on the ''German data set'' to a different shared space environment from China. Our results indicate that although the model faces difficulties replicating road users' motion from a new environment, by adding social norms (derived through analysis) of that environment to our model, satisfactory improvement of model accuracy can be obtained with little effort. [ABSTRACT FROM AUTHOR]

In most habitats in temperate zones, species show clear intra-annual shifts in abundance and species composition. Here we aimed to present a comprehensive picture of community composition and seasonal dynamics of carabid beetles (Coleoptera: Carabidae) in broad-leaved Korean pine mixed forest in Northeast China, which harbors a large diversity. We sampled 23,336 individuals from 14 genera and 39 species with pitfall traps over more than 1 year in a 25-ha plot. The six most abundant species accounted for 76.65 % of all individuals. Species estimations for the 25 ha plot ranged from 40 to 45 species. Overall abundance, species diversity, community composition, and abundance of individual species varied seasonally. Most of the abundant species showed an activity pattern of single peak, and were most active between July and early September. Few species showed a bimodal seasonal activity pattern. Both temperature and precipitation significantly influenced the carabid community within a year. Hierarchical clustering indicated that carabid communities of ten consecutive sampling periods could be partitioned into three time-windows, respectively, corresponding with warm temperature-high rainfall season, warm temperature-low rainfall season, and cool and cold season. By using the extended method of indicator species analysis, 11 indicator species were identified for the three time-groups and their combinations, suggesting the existence of temporal niche partitioning among carabid species. We suggest that intra-annual patterns of carabid abundance and species composition can be explained by species responses to seasonal changes in hydrothermal conditions. Cost-effective sampling effort to assess native carabid diversity and assemblage was also discussed in this study. [ABSTRACT FROM AUTHOR]

• Carbon sequestration of decaying logs via humification is determined by wood trait. • Wood trait has a stronger effect on the humification of heartwood and sapwood than on bark. • The humified carbon in sapwood is in favour of organic carbon accumulation in nutrient-poor soil. Deadwood is an indispensable component of forest ecosystems, with important consequences for global carbon cycling. Although research into carbon release from decaying logs and its response to wood traits has increased, little attention has been paid to how wood traits affect the potential of carbon sequestration in decaying logs through humification. To evaluate the wood trait effects, we measured the concentrations (mg g−1) and content (mg cm−3) of humus, including humic substrates, humic acid, and fulvic acid, and the degree of humification (%) separately in bark, sapwood, and heartwood in a four-year log decomposition experiment in a subalpine Minjiang fir forest on the eastern Qinghai-Tibet Plateau, China. We found the highest humus concentrations and humification degree in bark and the lowest in sapwood. The humus mass had a net loss in bark and did not change in sapwood over time. As decomposition proceeded, the humus mass in heartwood firstly accumulated and then decreased. In addition, wood traits strongly affected the humification of sapwood and heartwood compared to bark. Lignin and its interactions with cellulose and N concentrations were associated with sapwood humification. Nutrient conditions like N and P concentrations and the C/N ratio were related to heartwood humification. These findings suggest that wood traits can determine the potential of carbon sequestration of decaying logs through humification and that the large proportion of sapwood in decaying logs has a positive effect on long-term and stable carbon sequestration in poor soils in subalpine forests. [ABSTRACT FROM AUTHOR]