Polypore funga and species diversity in tropical forest ecosystems of Africa,America and Asia,and a comparison with temperate and boreal regions of the Northern Hemisphere

Polypores play a cru cial role in energy recycling and forest regeneration in forest ecosystems.The majority of them are wood degraders;some are forest pathogens and others are ectomycorrhizal symbionts.The basidiocarps provide food and shelter for many organisms,mostly invertebrates,but also some vertebrates,as well as food and medicine for humans.Despite extensive research on the species diversity and phylogenetic relationships of polypores in recent years,there remains a lack of comprehensive understanding of their distribution patterns and species composition at the large scale.Checklists of polypores from the tropical zone,including tropical Africa,tropical America,and tropical Asia,were analyzed for species diversity,distribution patterns,major taxa,and nutritional modes.A total of 1,902 polypore species was found in the three regions,representing 8 orders,46families,and 250 genera of Agaricomycetes.The orders Polyporales(especially the family Polyporaceae)and Hymenochaetales(especially the family Hymenochaetaceae)had the most prolific taxa,with their species accounting for 93.4%of the total polypores listed.Each of 1,565(or 82.3%)of the total 1,902 species were found in only one of the three regions studied,and we treat them temporarily as"regional endemic species".Only 141species were shared among all three regions,accounting for a mere 7.4%.Tropical Africa and tropical America had the greatest number of shared species and the highest S?rensen similarity index(SC)value.Tropical forests had a higher species richness compared with temperate to boreal forests of the Northern Hemisphere,and in addition,also a higher proportion of white rot polypores compared to brown rot and ectomycorrhizal species.This study outlines the distribution patterns and species diversity of polypores in the world,shedding light on their ecological significance in diverse ecosystems.

A comparison of polypore funga and species composition in forest ecosystems of China,North America,and Europe

Background:Polypores as components of forest ecosystems are an important group of wood-inhabiting fungi playing a key role in forest regeneration. Previously, studies on polypore funga and diversity were focused on limited areas within one land mass only. What are the polypore funga and species composition for large-scale of China, North America and Europe? The funga and species composition of polypores in the three land masses will supply an important source of reference for the distribution patterns of polypores at species level or higher taxa. In the present study the diversity and species composition of polypores in China, North America and Europe are compared based on published data.Methods:The species diversity, species composition, major genera and nutritional modes of polypores in the three land masses are comparatively analyzed.Results:A grand total of 1,337 polypore species, belonging to 11 orders, 43 families and 168 genera, have been recorded in these three land masses of the Northern Hemisphere, of which 854 species occur in China, 547 species in North America, and 432 species in Europe. Polyporales, Hymenochaetales and Russulales are the three major orders, and Hymenochaetaceae, Polyporaceae, and Fomitopsidaceae are the three major families. The brown rot fungi Antrodia and Postia have highest number of species at generic level in the three land masses. The proportionally highest number of white rot polypore species is in China (78.81%), followed by North America (73.86%)and then Europe (67.82%);conversely, the proportion of brown rot polypores is highest in Europe (28.47%) then North America (21.39%) and then China (15.57%).Conclusions:China had the highest polypore diversity followed by North America, and then Europe although North America is around twice as big as China and Europe. White rot is the major nutritional mode of all the polypores in China, North America and Europe accounting for 77.04%of all polypore species. The white rot species as a proportion of all polypores in each of the three land masses are highest in China, followed by North America and then Europe. The polypore diversity patterns are probably due to tree species diversity and the distribution patterns of angiosperm and gymnosperm trees in the three land masses. More tree species and diverse forest types are in China than those in North America and Europe, and these factors may correspond polypore funga and species composition in the three land masses.

Positioning taxonomic research for the future

Why do taxonomists matter? The work of taxonomists is often understated if not completely misunderstood. Without taxonomists, organisms cannot be accurately identified, neither can these organisms be given universally accepted names, and reliably positioned in the phylogenetic tree of life. Thanks to the work of taxonomists over the last 269 years since Carl Linnaeus established the binomial system, we can now measure the health and wealth of our biodiversity in a refined, science-based inventory prescribed by stringent nomenclatural rules.

Building segmentation and outline extraction from UAV image-derived point clouds by a line growing algorithm

This paper presents an approach to process raw unmanned aircraft vehicle(UAV)image-derived point clouds for automatically detecting,segmenting and regularizing buildings of complex urban landscapes.For regularizing,we mean the extraction of the building footprints with precise position and details.In the first step,vegetation points were extracted using a support vector machine(SVM)classifier based on vegetation indexes calculated from color information,then the traditional hierarchical stripping classification method was applied to classify and segment individual buildings.In the second step,we first determined the building boundary points with a modified convex hull algorithm.Then,we further segmented these points such that each point was assigned to a fitting line using a line growing algorithm.Then,two mutually perpendicular directions of each individual building were determined through a W-k-means clustering algorithm which used the slop information and principal direction constraints.Eventually,the building edges were regularized to form the final building footprints.Qualitative and quantitative measures were used to evaluate the performance of the proposed approach by comparing the digitized results from ortho images.