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The Red River Basin is located in the Indo-Burma biodiversity hotspot and is rich in lignicolous freshwater fungi, but no systematic research has been conducted. A systematic study on the species diversity of lignicolous freshwater fungi in the basin is ongoing. Seven distoseptispora-like specimens were collected from the Red River Basin in Yunnan. Phylogenetic analysis of ITS, LSU, tef1-a, and rpb2 genes and combined morphological data indicate that there are six distinct species of Distoseptispora, including two new species and four known species. Two new species were named D. suae and D. xinpingensis, and the four known species were D. bambusae, D. euseptata, D. obpyriformis and D. pachyconidia. This study provides detailed descriptions and illustrations of these six species and an updated phylogenetic backbone tree of Distoseptispora. [ABSTRACT FROM AUTHOR]

The 2014 Mw 6.2 Ludian earthquake exhibited a structurally complex source rupture process and an unusual spatial distribution pattern of co-seismic landslides. In this study, we constructed a spatial database consisting of 1470 co-seismic landslides, each exceeding 500 m2. These landslides covered a total area of 8.43 km2 and were identified through a comprehensive interpretation of high-resolution satellite images taken before and after the earthquake. It is noteworthy that the co-seismic landslides do not exhibit a linear concentration along the seismogenic fault; instead, they predominantly extend along major river systems with an NE–SW trend. Moreover, the southwest-facing slopes have the highest landslide area ratio of 1.41. To evaluate the susceptibility of the Ludian earthquake-triggered landslides, we performed a random forest model that considered topographic factors (elevation, slope, aspect, distance to rivers), geological factors (lithology), and seismic factors (ground motion parameters, epicentral distance, distance to the seismogenic fault). Our analysis revealed that the distance to rivers and elevation were the primary factors influencing the spatial distribution of the Ludian earthquake-triggered landslides. When we considered the directional variation in ground motion parameters, the AUC of the model slightly decreased. However, incorporating this variation led to a significant reduction in the proportion of areas classified as "high" and "very high" landslide susceptibility. Moreover, SEDd emerged as the most effective ground motion parameter for interpreting the distribution of the co-seismic landslides when compared to PGAd, PGVd, and Iad. [ABSTRACT FROM AUTHOR]

Longchuan River Basin is located in Chuxiong (central Yunnan province, China) that is subject to severe drought. Agriculture is critical to local economy, which can lead to intense agricultural activity. Accordingly, delineating groundwater potential zones and developing usable groundwater resources are required to meet potable and irrigating water demands in the zone. Remote sensing (RS), geographic information system (GIS) and improved fuzzy analytic hierarchy process (FAHP) were adopted to delineate the groundwater potential zones to assess the groundwater availability in Longchuan River Basin. The surveys of China geological map, Landsat 8 OLI and GDEM Aster satellite images were employed to generate eight thematic layers, i.e., lithology, land use/land cover (LULC), lineaments density, rainfall, slope, normalized difference vegetation index (NDVI), drainage density and elevation; subsequently, the mentioned layers were converted into raster data in ArcGIS. According to the ability of thematic layer to impact groundwater potential, the mentioned criteria were weighted differently by improved FAHP. Next, a map based on weighted linear combination (WLC) model was generated. Lastly, the groundwater potential zones of study area fell into 'poor' zone, 'moderate' zone and 'good' zone. As revealed from the results of the study, nearly 31.22% of the area exhibited 'good' groundwater potential, approximately 36.46% was terrain exhibiting 'moderate' groundwater potential, and the residual 32.23% were considered to exhibit 'poor' groundwater potential. The results provide more insights, and the groundwater potential zones map can be exploited by local governments for groundwater resources management and exploitation. [ABSTRACT FROM AUTHOR]

The current genetic structure of a species is determined by both historical demographics and contemporary gene flow among populations. As an economically important snail in China, Bellamya has attracted much attention for its breeding and aquaculture and has provided a good study system for this theoretical structure. Our results showed that high genetic diversity occurred in most populations distributed in the Pearl River basin, except for the population in Nanning, Guangxi Zhuang Autonomous Region. A lack of distinct genealogical branches or geographic clades was found for the Bellamya complex across the Pearl River basin. Nevertheless, low but significant genetic structure and high differentiation were detected between Anshun (in Guizhou Province) and other geographic populations segregated by the Yunnan–Guizhou Plateau, suggesting that geographic barriers exist around this region, while this scenario was not applicable to the populations in Yuxi, Yunnan Province. The demographic history described a relatively stable pattern before the last glacial period, but the effective population sizes have drastically decreased since the late Pleistocene. The lack of genetic structure across the Pearl River basin is mainly attributed to a high level of gene flow by passive migration due to flooding and anthropogenic and animal translocation. The vicariance caused by the uplift of the Yunnan–Guizhou Plateau during the early Pleistocene likely contributed to the divergence of the plateau and plain sublineages in the Pearl River basin. A genetic diversity and phylogeography analysis are valuable to developing further guidance on breeding and conservation strategies for Bellamya germplasm resources. [ABSTRACT FROM AUTHOR]

Qilu Lake is one of the 9 plateau lakes in Yunnan, China, with a lake surface altitude of 1796.62 m above sea level. In spite of the importance and agriculturally-intensive phenomenon in Qilu Lake Basin, few studies have provided a modern evaluation of pesticide residues and potential effects to local aquatic organisms. The primary goal of this study was to determine the spatio-temporal variations of organochlorine pesticides (OCPs) in this area, and to further assess the related ecological risks. Of the 25 OCPs analyzed, 14 were detected, and the concentrations of ∑ 25 OCPs were highest in the upstream of rivers, followed by regions close to the lake shore, and the lowest concentrations were found in Qilu Lake in every season except winter. The concentrations of ∑ 25 OCPs were the highest in summer, and the lowest in winter. OCP concentrations in spring and in autumn were similar. 4,4′-DDD, γ-HCH, HCB, trans -chlordane, and cis -chlordane were 5 OCPs with relatively high risk in Qilu Lake Basin. Interestingly, higher OCP concentrations do not necessarily correspond to higher ecological risk levels. Low predicted no-effect concentration (PNEC) values and relatively high toxicity of these OCPs led to their high risk quotient (RQ) values. This work further illustrated that although OCPs have been banned for many years, they were still frequently detected in surface waters, and caused risks to aquatic animals. [Display omitted] • OCPs concentrations were highest in the upstream of rivers and in summer. • Intensive precipitation in summer strongly affected pesticide migration. • Pesticides with similar properties had similar migration pathways. • Sediments could be a major source of OCP residues in waters. • γ-HCH presented the highest-risk level in Qilu Lake Basin. [ABSTRACT FROM AUTHOR]

Historical drainage patterns adjacent to the Qinghai-Tibetan Plateau differed markedly from those of today. We examined the relationship between drainage history and geographic patterns of genetic variation in the Yunnan spiny frog, Nanorana yunnanensis, using approximately 981 base pairs of mitochondrial DNA partial sequences from protein-coding genes ND1 and ND2, and intervening areas including complete tRNAIle, tRNAGln and tRNAMet. Two null hypotheses were tested: (i) that genetic patterns do not correspond to the development of drainage systems and (ii) that populations had been stable and not experienced population expansion, bottlenecking and selection. Genealogical analyses identified three, major, well-supported maternal lineages, each of which had two sublineages. These divergent lineages were completely concordant with six geographical regions. Genetic structure and divergence were strongly congruent with historical rather than contemporary drainage patterns. Most lineages and sublineages were formed via population fragmentation during the rearrangement of paleodrainage basins in the Early Pliocene and Early Pleistocene. Sympatric lineages occurred only in localities at the boundaries of major drainages, likely reflecting secondary contact of previously allopatric populations. Extensive population expansion probably occurred early in the Middle Pleistocene accompanying dramatic climatic oscillations. [ABSTRACT FROM AUTHOR]

• Incorporate the ecological security pattern into the constraints of future land use simulation. • Integrate future building land expansion with the ecological security pattern to identify ecological early warning areas. • Considering land use types, propose ecological restoration strategies for ecological restoration and early warning areas. The scientific determination of crucial regions for ecological land restoration and reasonable early warnings for ecologically weak areas are vital for implementing land ecological restoration. Five major plateau lake basins in central Yunnan (China) are selected as the study area in this research. An ecological security pattern (ESP) is constructed using the source-resistance surface-corridor-pinch point framework to effectively identify crucial areas for ecological restoration. Finally, the land use/cover change (LUCC) in the study region in 2030 is simulated in terms of the natural development prospect (NDP), with priority given to urban development (PUD) and priority given to ecological protection (PEP) scenarios, and identify areas where future urban expansion poses a threat to current ecological source areas and corridors as early warning regions. The results indicate the following: (1) There are 15 ecological source regions in the Five Lakes Basin, mainly forestland and waters, with a total area of 787.54 km2. The ecological corridor spans 245.72 km, with a total area of 439.90 km2. (2) The key ecological restoration areas include 72.87 km2 of ecological pinch points, 70.46 km2 of barrier points of ecological, and 71 breakpoints. (3) The ecological land under the NDP scenario and the PUD scenario were damaged to varying degrees. The ecological land dominated by forestland and water area under the PEP scenario is effectively protected. (4) The seven ecological protection space early warning points are mainly distributed in the eastern part of Dianchi Lake and the northern part of Fuxian Lake, which have good economic development and better habitat quality. The comprehensive analysis identified key ecological restoration areas and identified future ecological stresses due to land use change in the Five-Lakes Basin. Restoration strategies are proposed based on current land use and future scenarios to enhance the ESP in central Yunnan's Five Lakes Basin. [ABSTRACT FROM AUTHOR]