31 research outputs found
Predicted occurrence of ancient coppice woodlands in the Czech Republic
Coppicing started in the Neolithic period and has been practiced throughout European history. This traditional silvicultural system was abandoned in many European countries during the 20th century. The Czech Republic now has a very low proportion of coppice woods (CW), as more than 1000 km2 CW were converted into high forests after World War II. Nevertheless, many CW were maintained as stored coppices, which could be the last remainders of ancient coppice woods (ACW) in the Czech Republic. Knowledge of area and distribution of stored coppices is currently missing in the Czech Republic, because they are recorded as high forests in forest management plans. Many stored forests are currently approaching the maturity age, with a high risk that these last ACW remainders will be lost; therefore, an inventory of ancient coppice woods is necessary. In our study, we develop an index of likelihood of coppice occurrence (COP) based on the distribution of habitats favourable for coppices, as well as on past and current occurrence of CW in the Czech Republic from historical maps. COP index values were then used to generate a map showing the relative likelihoods of occurrence of ACW, which can serve as a baseline to support the compilation of an ACW inventory and their mapping in the field. Our results can help prioritize forest areas to be inventoried based on their higher probabilities of ACW occurrence.O
Effects of mild drought on the morphology of sun and shade needles in 20-year-old Norway spruce trees
Several studies have looked at how individual environmental factors influence needle morphology in conifer trees, but interacting effects between drought and canopy position have received little attention. In this study, we characterized morphological responses to experimentally induced drought stress in sun exposed and shaded current-year Norway spruce needles. In the drought plot trees were suffering mild drought stress, with an average soil water potential at 50 cm depth of -0.4 MPa. In general, morphological needle traits had greater values in sun needles in the upper canopy than in shaded needles in the lower canopy. Needle morphology 15 months after the onset of drought was determined by canopy position, as only sun needle morphology was affected by drought. Thus, canopy position was a stronger morphogenic factor determining needle structure than was water availability. The largest influence of mild drought was observed for needle length, projected needle area and total needle area, which all were reduced by ~27% relative to control trees. Needle thickness and needle width showed contrasting sensitivity to drought, as drought only affected needle thickness (10% reduction). Needle dry mass, leaf mass per area and needle density were not affected 15 months after the onset of mild drought. Our results highlight the importance of considering canopy position as well as water availability when comparing needle structure or function between conifer species. More knowledge about how different canopy parts of Norway spruce adapt to drought is important to understand forest productivity under changing environmental conditions.publishedVersio
The comparative study of the surface of the quartz grains at the south and southeast Moravia sites
Between 2013–2014, archeological researches at the Mikulčice site were performed. During these researches, necessity of a quartz grains surface study in the Moravian Sahara arose. There is a significant archaeological monument situated near the village of Mikulčice – a Slavic settlement, whose youngest bedrock is formed by fluvial sediments of extinct riverarms of the river Morava, and sand dunes composed of wind-blown sands of the Moravian Sahara. On these sand dunes, the most important churches and palaces of the settlement are found. The sandy sediments can reach up to 30 m thickness in the area of the Moravian Sahara.Samples of sandy sediments were taken from several locations of this site, and also from several other sites of south Moravia, which are sedimentary genetically different from the studied area. One sample of aeolian sand from the desert Rub-al Khali of Arabian Peninsula was provided for comparison.After gathering this small collection of sand grain samples, they were individually modified to the required study form and analyzed according to the demands of the method of exoscopy. At first, one hundred quartzgrains were separated from each sample of the collection using a stereo microscope. After that a detailed study and imaging with the scanning electronmicroscope (SEM) followed.The collection of sands from Mikulčice of the same genetical origin was compared to other samples of genetically known origin (fluvial, eolian...). The final comparison of all samples was performed by the method of multivariate analysis with NMDS. The results show that development of sediments at the archeological site Mikulčice most probably took place in very similar sedimentary environment. In this environment, the eolian transport and the fluvial transport with lower kinetic energy played important role. Between 2013–2014, archeological researches at the Mikulčice site were performed. During these researches, necessity of a quartz grains surface study in the Moravian Sahara arose. There is a significant archaeological monument situated near the village of Mikulčice – a Slavic settlement, whose youngest bedrock is formed by fluvial sediments of extinct riverarms of the river Morava, and sand dunes composed of wind-blown sands of the Moravian Sahara. On these sand dunes, the most important churches and palaces of the settlement are found. The sandy sediments can reach up to 30 m thickness in the area of the Moravian Sahara.Samples of sandy sediments were taken from several locations of this site, and also from several other sites of south Moravia, which are sedimentary genetically different from the studied area. One sample of aeolian sand from the desert Rub-al Khali of Arabian Peninsula was provided for comparison.After gathering this small collection of sand grain samples, they were individually modified to the required study form and analyzed according to the demands of the method of exoscopy. At first, one hundred quartzgrains were separated from each sample of the collection using a stereo microscope. After that a detailed study and imaging with the scanning electronmicroscope (SEM) followed.The collection of sands from Mikulčice of the same genetical origin was compared to other samples of genetically known origin (fluvial, eolian...). The final comparison of all samples was performed by the method of multivariate analysis with NMDS. The results show that development of sediments at the archeological site Mikulčice most probably took place in very similar sedimentary environment. In this environment, the eolian transport and the fluvial transport with lower kinetic energy played important role
Soil Microbial Functional Diversity under the Single-Season Influence of Traditional Forest Management in a Sessile Oak Forest of Central Europe
This one-year study focuses on the responses of a soil environment to the implementation of traditional forest management practices in oak-hornbeam stands with the following treatments: cut (C), cut + litter raking (CR), cut + grazing (CG), cut + litter raking + grazing (CRG) and control (Ctrl). The cut was conducted in 2018 through extremely heavy thinning. In autumn of 2017 and 2018, we sampled the soils, focusing on microbial functional diversity (FD) assessments using BIOLOG EcoplateTM. After one season, the FD was the highest in the Ctrl stand and the lowest in the CRG stand. Furthermore, we detected significant seasonal differences in soil reaction, nitrate nitrogen content, phosphatase activity and microbial biomass among the treatments. In particular, the Ctrl stand was defined via FD indices and biochemical and biological soil properties that contrasted mainly with those of the CRG stand defined by the content of mineral nitrogen forms. The soil properties did not differ substantially in the remaining treatments. Of the 31 carbon sources defining FD, 6 were treatment-specific (putrescine, L-arginine, L-serine, L-threonine, D-cellobiose and glycogen), while the remaining carbon sources mainly displayed either uniform high or low activity across the treatments.O
Growth dynamics of Dracaena cinnabari under controlled conditions as the most effective way to protect endangered species
Dracaena cinnabari Balf. fil. is an endangered endemic species growing on the Yemeni island of Soqotra. Dracaena woodlands are considered as one of the oldest forest communities on Earth. Uncontrolled grazing unfortunately caused a lack of naturally occurring regeneration. Our two-year research was focused on the growth dynamics of Dracaena seedlings from two separate populations. One hundred of germinated seeds from two different altitudes from the island were sown and planted under the same conditions. Average increment and difference between the growth dynamics of plants from the two localities were investigated. The observed data on this plant species revealed very interesting, hitherto unknown results. (1) The seedlings germinated within a time period from four to ten weeks. Germination rate was 90% on the Firmihin highland plateau and 78% on the Scand Mountain. (2) Average plant length from both localities was almost the same (24.9Â cm) at the end of measurement. Differences in values between the two populations proved as non-significant. (3) A significant difference was found in the number of leaves and in the sum of lengths of all leaves on one plant. While the seedlings from Firmihin featured a wide spreading above-ground part with a large number of leaves, the plants from Scand invested more energy into faster leaves elongation rate. (4) Growth dynamics reflected seasonal changes. Increments were slower or ceased during the period of vegetative rest from autumn to spring. (5) Average mortality rate was 13%. Most of the plants died during the period of vegetative rest. Further study on germination and regeneration under artificial conditions seems like the only way to prevent species extinction
Data from: Optimisation of AFLP for extremely large genomes over 70 Gb.
Here, we present an improved amplified fragment length polymorphism (AFLP) protocol using restriction enzymes (AscI and SbfI) that recognise 8-base pair sequences to provide alternative optimisation suitable for species with a genome size over 70 Gb. This cost-effective optimisation massively reduces the number of amplified fragments by using only +3 selective bases per primer during selective amplification. We demonstrate the effects of the number of fragments and genome size on the appearance of non-identical co-migrating fragments (size homoplasy), which has a negative impact on the informative value of AFLP genotypes. We also present various reaction conditions and their effects on reproducibility and the band intensity of the extremely large genome of Viscum album. The reproducibility of this octo-cutter protocol was calculated using several species with genome sizes ranging from 1 Gb (Carex panicea) to 76 Gb (Viscum album). The improved protocol also succeeded in detecting high intraspecific variability in species with large genomes (Viscum album, Galanthus nivalis and Pinus pumila)
AFLP in silico size homoplasy
The file contains a script for R package that simulate size homoplasy for AFLP fragments