Post Hoc Assessment of Stand Structure Across European Wood-Pastures: Implications for Land Use Policy

Europe’s woodland and savanna rangelands, often part of silvopastoral systems known as wood-pastures, are deteriorating because of abandonment that leads to return to a forested state or lack of tree regeneration from overgrazing or tree and shrub removal. Despite numerous local studies, there has been no broader survey of the stand structure of European wood-pastures showing which systems are at risk of losing their semiopen character. This overview aims to 1) show some of the differences and similarities in wood-pastures from landscapes across Europe and 2) identify which of these wood-pastures are at risk of losing their semiopen character. We collated a dataset of 13 693 trees from 390 plots in wood-pastures from eight different European regions (western Estonia, eastern Greece, northern Germany, Hungary, northern Italy, southern Portugal, central Romania, and southern Sweden), including tree diameters at breast height, tree density, management type, and tree species composition. On the basis of their structural characteristics, we classified wood-pastures using principal component analysis (PCA) and cluster analysis. The PCA showed a gradient from dense wood-pastures with high levels of regeneration (e.g., in Estonia) to sparse wood-pastures with large trees but a lack of regeneration (e.g., in Romania). Along this gradient, we identified three main groups of wood-pastures: 1) sparse wood-pastures with mostly big trees; 2) dense wood-pastures composed of small trees, and 3) wood-pastures containing a wide range of tree ages. Our results show a large structural gradient in European wood-pastures, as well as regeneration problems varying in their severity, highlighting the importance of social-ecological context for wood-pasture conditions. To maintain the ecological and cultural integrity of European wood-pastures, we suggest 1) more comprehensively considering them in European policies such as the Common Agricultural Policy and EU Habitats Directive, while 2) taking into account their structural characteristics and social-ecological backgrounds.     

Water absorption characteristics of kenaf core to use as animal bedding material

Kenaf is grown these days as a minor fibre crop in some Asian countries, but also in the US and recently in Southern European countries such as Italy. The yield of extracted bast fibres is below 1/3 of that of the kenaf stem weight. In the US and Europe a profitable outlet for the remaining woody core is important for economical production of the crop. The use of kenaf core as animal bedding material is considered here as potential market outlet. An important aspect for this application is the moisture absorption capacity of the material. This paper describes evaluation of the water absorption capacity of different kenaf core fractions in comparison with other commercial animal bedding materials like straw and wood shavings. The water absorption of kenaf core particles is shown to be in the range of the other tested materials and especially the soft pith material showed very high absorbency.     

Effects of Environmental Stress on Forest Crown Condition in Europe. Part IV: Statistical Analysis of Relationships

Site-specific estimates for various environmentalstress factors were related with measured crowncondition data at a systematic 16 ×: 16 km² gridover Europe, according to previously statedhypotheses, using a multiple regression approach,including interactions, and lagged effects of stressfactors. Methodological differences among countriesaccounted for >30% of the variation in defoliation.Nevertheless, crown condition was found to varynaturally with tree age, altitude, drought stress and,most likely, also pathogenic fungi and insects.Significant impacts of air pollution (specificallyozone but also NO_x, SO_x and acid deposition)were found at regional levels in parts of centralEurope, particularly for deciduous species. Impactsseemed less significant for conifers, especially forspruce, but this might be affected by confoundingeffects or strong correlations between (a harsh)climate and (low) atmospheric deposition in the areawhere spruce predominates. National studies indicatethat ozone and acid deposition can have a significanteffect on the defoliation of spruce as well. Weconclude that while forest condition varies naturally,continued emissions will contribute further to forestdecline in the long term.     

Oribatid communities (Acari: Oribatida) inhabiting saxicolous mosses and lichens in the Krkonoše Mts. (Czech Republic)

Composition, structure and diversity of oribatid communities inhabiting saxicolous mosses and lichens were studied in the Krkonoše Mts. (Czech Republic) along an altitudinal gradient reaching from submontane to alpine belt. Samples of various saxicolous mosses and lichens from 197 stands were collected. Impact of altitude and dominant moss or lichen species on community structure were analysed. Data were evaluated using divisive cluster analysis and direct ordination analysis. Altogether 104 oribatid species were recorded. Four groups of saxicolous habitats, which differ in the composition of their oribatid communities, were distinguished:1. Mosses below the upper forest line with accessory higher plants growing on their surface. Higher plants indicate favourable moisture conditions and an appreciable degree of humus layer development. Their oribatid mite community is rich in number of frequent species and consists of ubiquitous species, ubiquitous species with higher requirements for moisture and amount of decaying organic matter, a high number of soil dwelling species and several hygrophilous species.2. Mosses below the upper forest line without accessory higher plants. They predominantly include mosses with no or only a weakly developed humus layer. Their oribatid mite community is composed mainly of ubiquitous species and a few soil dwelling species.3. Mosses in open areas above the upper forest line. Their humus layer is not developed at all or only weakly. Humidity and temperature fluctuations are here much higher compared with mosses below the upper forest line, which are protected by the specific forest microclimate. Their oribatid mite community is poor in number of frequent and dominant species and consists predominantly of Oribatula cf. pallida and two specialised species living exclusively in mosses and lichens (Mycobates tridactylus and Trichoribates monticola).4. Saxicolous lichens. Their oribatid community comprises ubiquitous species, species frequent both in mosses and lichens and several species with a strong affinity to lichens (Mycobates carli and five species of the genus Carabodes).     

Inhibition of enzymatic browning of chlorogenic acid by sulfur-containing compounds

The antibrowning activity of sodium hydrogen sulfite (NaHSO(3)) was compared to that of other sulfur-containing compounds. Inhibition of enzymatic browning was investigated using a model browning system consisting of mushroom tyrosinase and chlorogenic acid (5-CQA). Development of brown color (spectral analysis), oxygen consumption, and reaction product formation (RP-UHPLC-PDA-MS) were monitored in time. It was found that the compounds showing antibrowning activity either prevented browning by forming colorless addition products with o-quinones of 5-CQA (NaHSO(3), cysteine, and glutathione) or inhibiting the enzymatic activity of tyrosinase (NaHSO(3) and dithiothreitol). NaHSO(3) was different from the other sulfur-containing compounds investigated, because it showed a dual inhibitory effect on browning. Initial browning was prevented by trapping the o-quinones formed in colorless addition products (sulfochlorogenic acid), while at the same time, tyrosinase activity was inhibited in a time-dependent way, as shown by pre-incubation experiments of tyrosinase with NaHSO(3). Furthermore, it was demonstrated that sulfochlorogenic and cysteinylchlorogenic acids were not inhibitors of mushroom tyrosinase.     

Cultivar variability of patatin biochemical characteristics: table versus processing potatoes (Solanum tuberosum L.)

Biochemical characteristics of patatin proteins purified by ion-exchange and affinity chromatography from tubers of 20 potato cultivars were studied to evaluate their genotype differences with respect to utility groups, table potato cultivars (TPCs) and processing potato cultivars (PPCs). Both groups of cultivars showed similar values of protein content in dry matter (3.98-7.39%) and of patatin relative abundance (5.40-35.40%). Three mass levels (～40.6, 41.8, and 42.9 kDa) of purified patatins were found by MALDI-TOF MS within all cultivars. Differences among mass levels corresponding with the mass of sugar antenna (～1.2 kDa) confirmed the previous concept of different glycosylation extentsin patatin proteins. It was showed that the individual types of patatin varying in their masses occur in the patatin family in a ratio specific for each of the cultivars, with the lowest mass type being the major one. Electrophoretic analyses demonstrated wide cultivar variability in number of patatin forms. Especially 2D-PAGE showed 17-23 detected protein spots independently on the utility group. Specific lipid acyl hydrolase (LAH) activity of purified patatins from the individual tested cultivars varied between 0.92 and 5.46 μmol/(min mg). Patatin samples within most of the TPCs exhibited higher values of specific LAH activity than samples of PPCs. It may be supposed that individual patatin forms do not have similar physiological roles.     

The burden of genetic diversity

In general, species with large ecological amplitudes are equipped with high genetic diversities. In contrast, more specialised species with narrow ecological amplitudes show low levels of genetic diversity. Generalist species are mostly rather marginally affected by recent land-use changes; specialist can be supported by specific conservation measures. We argue that, in the light of Conservation Genetics, species being ecologically intermediate between these two extremes are the most seriously affected ones by recent environmental changes. Such species which formerly occurred in large population networks have to sustain their high level of genetic variability via gene flow. Today, species from the latter group are negatively affected by rapid habitat collapses causing sudden lacks of population interconnectivity. Therefore, species with intermediate habitat demands and originally high genetic diversity might be at highest risk due to inbreeding depressions.