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The multifaceted role of deadwood in forest ecosystems has been widely recognized while it is regarded as an indicator of sustainable forest management. Nevertheless, there are hardly any data on deadwood volume and structure in managed forests in Greece. The study took place in beech forests of the Western and Central part of the Rodopi Mountain Range. The objective was to determine the amount, variability and quality of deadwood and to compare it with data from managed as well as natural forests. Data were collected on 30 randomly distributed circular plots of 0.1 ha. The results showed that the average deadwood amount (13.46 m3 ha−1) was much lower compared to that recorded in other European forests and they highlighted the absence of large dead standing trees due to the management regime. The deadwood quality showed great variation in stages of decay. [ABSTRACT FROM AUTHOR]

Downed logs are important structural and functional elements in the material flow of global forest ecosystems. They provide a rich natural substrate resource for microorganisms; however, current laboratory-based methods cannot fully elucidate the complex process of microbial decomposition of downed logs. Therefore, our study investigated the microbial community structure, succession patterns, and underlying environmental factors controlling the decomposition of Pinus tabulaeformis and Quercus aliena var. acuteserrata downed logs at different stages of decomposition in Chinese forest ecosystems. The genomes of the microorganisms present on the logs during different stages were therefore sequenced, and functional genes were annotated and analyzed using the Kyoto Encyclopedia of Genes and Genomes and Carbohydrate-Active enZYmes databases. We found that bacterial abundance was always higher than fungal abundance throughout the decomposition process, reflecting their strong competitive ability. Microbial community structure and function were similar in the early stage (I) and late stages (IV, V) of log decomposition, but those of the middle stages (II, III) differed. With the decomposition of downed logs of Q. aliena var. acuteserrata , there was a fungal succession pattern from Ascomycota to Basidiomycota to Mucoromycetes , but this trend did not occur for P. tabulaeformis. The density, moisture and elemental content of downed logs were the main factors affecting the microbial community. Finally, microbially mediated functions were mainly related to the metabolism of amino acids, carbohydrates and various small molecule carbohydrate enzymes, cellulases, and chitinases in glycoside hydrolases; the taxa sources of the main functions were primarily Proteobacteria and Firmicutes bacteria, reflecting the functional importance of bacteria in the process of downed log decomposition. We conclude that bacteria always play an important role in the process of downed log decomposition and that their role may be far underestimated. Therefore, we believe that the next step should be to expand the study of downed log bacteria, to further clarify the ecological functions of the bacteria on downed logs in natural environments and their relationship with fungi, which may help shed light on the complex decomposition process of downed logs. Changes in characteristic microorganisms and their main functions on naturally decomposed downed logs (Pinus tabulaeformis and Quercus aliena var. acuteserrata). The characteristic microorganisms of downed logs at different stages of decomposition undertake different KEGG functions, and also produce different CAZymes to decompose downed logs. The physicochemical factors of downed log that mainly affect microorganisms are constantly changing. The microbial community structure and function of decomposition stages II and III are similar, while decomposition stages IV and V are similar (I, II, III, IV, V: five decomposition stages of downed logs; DOM: organic matter; DOC: organic carbon; DLTP: total phenol content; DLC: total cellulose content; DLH: total hemicellulose content). [Display omitted] • Bacteria were highly competitive in decomposing downed log. • Changes in microbial communities followed a succession pattern, but there were species differences. • Moisture, cellulose and element contents affected microbial communities. • Microbial function was related to the metabolism of amino acids and carbohydrates. • Microbes decomposed downed log by producing glycoenzymes, cellulase and chitinase. [ABSTRACT FROM AUTHOR]

Dead wood is one of the most important indicators of forest naturalness and the most important manageable habitat for biodiversity in forests. Standing and lying dead wood, and especially coarse woody debris, plays an important part in creating habitats for many highly specialized organisms, e.g., insects, fungi, lichens and bacteria. Temperate mixed deciduous forests, rich in species, have been studied only to a small extent from the point of view of the ecology of wood-related cryptogams. Our study aimed at the reduction of the gap in knowledge about the ecological characteristics of dead wood-dependent organisms by focusing on species of cryptogams developing on various dead wood structures typical of temperate non-beech forests. Studies were performed in forests located in Lithuania, Poland, Belarus and Russia. We recorded 48 species of cryptogams: 18 species of bryophytes, 24 species of fungi and 6 species of lichens developing on dead wood. Our study stresses the importance of all types of dead wood as a substrate for the development of rare cryptogam species. Logs were the most important substratum type for cryptogams, followed by snags, dead trees and stumps. The cryptogam species richness on logs was several times higher than on the three other types of substrata. Coarse logs of intermediate decay stages hosted the highest number of cryptogams, followed by freshly fallen logs and, finally, well decayed logs. Assessing the importance of dead wood quality for the studied cryptogams, we found that intermediate decay stages are extremely important for fungi, while bryophytes or lichens do not show a clear preference. The highest number of cryptogams was found on Fraxinus excelsior, Quercus robur and Picea abies, while other tree species had less than half cryptogam species. [ABSTRACT FROM AUTHOR]

Ecological succession is arguably the most enduring contribution of plant ecologists and its origins have never been contested. However, we show that French entomologist Pierre Mégnin, while collaborating with medical examiners in the late 1800s, advanced the first formal definition and testable mechanism of ecological succession. This discovery gave birth to the twin disciplines of carrion ecology and forensic entomology. As a novel case of multiple independent discovery, we chronicle how the disciplines of plant and carrion ecology (including forensic entomology) accumulated strikingly similar parallel histories and contributions. In the 1900s, the two groups diverged in methodology and purpose, with carrion ecologists and forensic entomologists focusing mostly on case reports and observational studies instead of hypothesis testing. Momentum is currently growing, however, to develop the ecological framework of forensic entomology and advance carrion ecology theory. Researchers are recognizing the potential of carcasses as subjects for testing not only succession mechanisms (without assuming space-for-time substitution), but also aggregation and coexistence models, diversity-ecosystem function relationships, and the dynamics of pulsed resources. By comparing the contributions of plant and carrion ecologists, we hope to stimulate future crossover research that leads to a general theory of ecological succession. [ABSTRACT FROM AUTHOR]

We examined the structure of the arthropod community among deciduous and coniferous dead woods along the process of wood decay. We collected dead wood-dwelling arthropods from April 2010 to October 2011 by using a vacuum aspirator and an electric chain saw in three areas ( Mt. Woonak, Mt. Wolchul, Mt. Jingang) in Korea. We identified them to species levels and classified them into functional groups. We collected 8792 arthropods (5 classes, 20 orders, 58 families, and 93 species). The species richness and abundance of arthropods increased with the progress of decay in dead woods. The evenness index seemed to be shown at a lower value at late decay stage than at early- and mid-decay stages. The diversity index ( H′) in conifers was lower than that in deciduous dead woods at the early decay stage but this situation was reversed at the late decay stage. Arthropod communities of functional groups, except the xylophagous insects, did not differ in the variables, but the proportion of xylophagous insects increased as the decay stages progressed. The abundance of arthropods and xylophagous was statistically significantly different. The patterns generated by non-metric multidimensional scaling in the overall arthropod community composition revealed that the species composition between study areas were significantly different. We confirmed that dead woods play very important roles as arthropods' habitats. Thus, we suggest that the role of dead woods should be emphasized in the management of forest ecosystems. [ABSTRACT FROM AUTHOR]