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Neoboletus infuscatus ( Boletaceae , Boletales ) is described as a new species from Yinggeling of Hainan Tropical Rainforest National Park, southern China. It is morphologically characterized by a large basidioma with a nearly glabrous, brownish yellow, yellowish brown to pale brown pileus, pores orangish red when young, yellowish brown to brown when old, context and hymenophore staining blue when injured, a yellow stipe with red punctuations, surfaces of the pileus and the stipe usually covered with a thin layer of white pruina when young. Phylogenetic analyses of DNA sequences from part of the 28S gene, the nuclear rDNA internal transcribed spacer (ITS) region, and part of the translation elongation factor 1-α gene ( TEF1 ) also confirm that N. infuscatus forms an independent lineage within Neoboletus . Detailed morphological description, color photos of fresh basidiomata and line-drawings of microstructures are provided., (2021, by The Mycological Society of Japan.)

A new species of flanged bombardier beetle form Hainan Island, China, Eustra yinggelingensis sp. nov. (Coleoptera, Carabidae, Paussinae, Ozaenini) is described. The new species was collected in rotten wood from Yinggeling Nature Reserve. Habitus and diagnostic features of the new species are illustrated. List, key and distribution map of all known Chinese Eustra species are given.

In tropical areas, a large number of natural forests have been transformed into other plantations, which affected the water conservation function of terrestrial ecosystems. In order to clari-fy the effects of land use changes on soil water conservation function, we selected four typical land use types in the central mountainous region of Hainan Island, i.e., natural forests with stand age greater than 100 years (VF), secondary forests with stand age of 10 years (SF), areca plantations with stand age of 12 years (AF) and rubber plantations with stand age of 35 years (RF). The effects of land use change on soil water holding capacity and water conservation (presented by soil water index, SWI) were assessed. The results showed that, compared with VF, the soil water holding capacity index of other land types decreased in the top soil layer (0-10 cm). AF had the lowest soil water holding capacity in all soil layers. Soil water content and maximum water holding capacity were significantly related to canopy density, soil organic matter and soil bulk density, which indicated that canopy density, soil organic matter and compactness were important factors influencing soil water holding capacity. Compared to VF, soil water conservation of SF, AF and RF were reduced by 27.7%, 54.3% and 11.5%, respectively. The change of soil water conservation was inconsistent in different soil layers. Vegetation canopy density, soil organic matter and soil bulk density explained 83.3% of the variance of soil water conservation. It was suggested that land use conversion had significantly altered soil water holding capacity and water conservation function. RF could keep the soil water better than AF in the research area. Increasing soil organic matter and reducing soil compaction would be helpful to improve soil water holding capacity and water conservation function in land management.

Rill erosion is an important process that occurs on hill slopes, including sloped farmland. Laboratory simulations have been vital to understanding rill erosion. Previous experiments obtained sediment yields using rills of various lengths to get the sedimentation process, which disrupted the continuity of the rill erosion process and was time-consuming. In this study, an improved experimental method was used to measure the rill erosion processes by concentrated channel flow. By using this method, a laboratory platform, 12 m long and 3 m wide, was used to construct rills of 0.1 m wide and 12 m long for experiments under five slope gradients (5, 10, 15, 20, and 25 degrees) and three flow rates (2, 4, and 8 L min(-1)). Sediment laden water was simultaneously sampled along the rill at locations 0.5 m, 1 m, 2 m, 3 m, 4 m, 5 m, 6 m, 7 m, 8 m, 10 m, and 12 m from the water inlet to determine the sediment concentration distribution. The rill erosion process measured by the method used in this study and that by previous experimental methods are approximately the same. The experimental data indicated that sediment concentrations increase with slope gradient and flow rate, which highlights the hydraulic impact on rill erosion. Sediment concentration increased rapidly at the initial section of the rill, and the rate of increase in sediment concentration reduced with the rill length. Overall, both experimental methods are feasible and applicable. However, the method proposed in this study is more efficient and easier to operate. This improved method will be useful in related research.