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The subfamily Sphaeriinae is a diverse and ecologically significant group of freshwater invertebrates, playing a keystone role in the energy flow and nutrient cycling in aquatic ecosystems. Despite a long history of its study, the taxonomic structure and species content of this group are a matter of ongoing disputes between malacologists. We clarify the taxonomy, distribution, and evolutionary biogeography of the Sphaeriinae around the world based on the largest dataset of DNA sequences of these clams ever accumulated, which includes the data on specimens collected from various continents and countries around the globe. Our 16S rRNA and two-locus phylogenies reveal that the Sphaeriinae is a monophyletic group, containing at least seven genus-level clades: Sphaerium Scopoli, 1777, Pisidium C. Pfeifffer, 1821 (s.s.), Euglesa Jenyns, 1832, Odhneripisidium Kuiper, 1962, Conventus Pirogov & Starobogatov stat. nov. 1974, 'Pisidium' sterkianum group, and Hindupisidium Vinarski & Bespalaya gen. nov. Our 16S rRNA phylogenetic tree contains 80 well-supported clades corresponding to the putative species-level taxa. Four species new to science are described here: Euglesa kolymensis Bespalaya, Aksenova & Bolotov sp. nov. , Euglesa kyrgyzica Bespalaya, Aksenova, Kondakov & Palatov sp. nov. , Euglesa moroccana Bespalaya, Vinarski, Aksenova, Mabrouki, Kondakov & Palatov sp. nov. , Odhneripisidium caucasus Bespalaya, Vinarski, Aksenova, Kondakov & Palatov sp. nov. Our fossil-calibrated phylogeny and generalized biogeographic model indicate that the most recent common ancestor of the Sphaeriidae could have originated somewhere within a broad area covering China near the Lower Cretaceous boundary. [ABSTRACT FROM AUTHOR]

Understanding the formation and causes of cropland abandonment is crucial for developing effective strategies to mitigate this process. However, studies on cropland abandonment often look at one spatial scale, although the relationship between abandonment and evaluated factors may change depending on the specific scale, which limits our understanding of the process of cropland abandonment. Taking mountainous Southern Sichuan of China as an example, we utilized satellite-derived cropland abandonment maps to assess the evolving patterns of cropland abandonment from 2003 to 2018 across various scales. We then carried out a multi-scale (parcel, local and regional) assessment of the relationships between selected 17 variables representing natural, location and socioeconomic conditions and cropland abandonment. Results showed, the cropland abandonment rate increased from 2 % in 2003 to 15 % by 2018, and cropland abandonment always showed a higher concentration in the central part of the study area. At different scales, a combination of factors, which determined cropland abandonment, differed. We also found the distance to the nearest county center was scale-dependent factor and statistically significant factor of cropland abandonment only at the local scale. Among the factors with large contributions, topography mattered at all three scales; cropland per capita, aging and agricultural labor per unit of cropland mattered at the parcel and regional scales. Cropland fragmentation, air temperature and distance to the nearest settlement mattered at the local scale; the distance to the nearest water system, the distance to nearest county center and agricultural mechanization mattered at the regional scale. This multi-scale assessment framework embodied with multi-variable and multi-temporal could provide a new perspective to reveal the complex nonlinear relationship between the determinants and cropland abandonment, and further help to predict future cropland abandonment hotspots and identify relevant land-use policies. • The clustering of cropland abandonment was revealed across multiple scales. • Abandonment patterns at various scales were explained by various determinants. • The topography factor mattered at parcel, local and regional scales. • Observed a nonlinear relationship between the determinants and land abandonment. [ABSTRACT FROM AUTHOR]

The rapid growth of the global population has resulted in a continuous increase in cropland intensity and a shortening of the fallow period as part of the cropland rotation cycle. Yet, there is a lack of systematic knowledge on the extent of fallow lands, particularly in complex landscapes, such as the mountainous regions of China. To fill this knowledge gap, taking Yuanyang County (YYC), Yunnan Province, China, as a case study, we tested a method to identify the spatial-temporal distribution of fallow land by mapping cropland with Landsat data. The overall accuracy of land cover classification, including cropland, ranged between 90.1% and 95.8% from 1998 to 2019. The average accuracy of fallow plots was 75.7% from 2001 to 2019. The annual fallow rate varied between 8.3% and 54.3%, with an average of 20.7%. Kernel density estimated with the probability density function showed that fallow varied between 5 and 13 blocks per km2, gradually decreasing from the central area to the periphery. Increasing elevation, the low value of regional domestic products, and the increased distance to rural settlements were closely related to the higher proportions of fallow land. The approach presented here can be applied to map fallow land in other regions. [ABSTRACT FROM AUTHOR]

Discoveries of new Hemiclepsis species (Hirudinea: Glossiphoniidae) in East and Southeast Asia were expected. A peculiar freshwater leech was found on the body surface of Asian Swamp Eel Monopterus albus (Synbranchiformes: Synbranchidae) in Jingzhou, Hubei Province, China. Here, we describe this leech species as Hemiclepsis yangtzenensissp. nov. It could be distinguished from other congeners based on a combination of morphological features such as very small size, translucent body with dense green reticulate markings throughout dorsum, very large posterior sucker with a characteristic reticulate pattern, and two pairs of well-developed drop-like eyespots. It also represents a phylogenetic lineage that is distant from other members of the genus based on the COI and 18S rRNA sequences. This leech species seems to be a specialized fish parasite that could negatively affect farming and wild stocks of Asian Swamp Eel in China. [ABSTRACT FROM AUTHOR]

Cropland abandonment is a widespread land-change process globally, which can stem from the accelerated outmigration of the population from rural to urban areas, socio-economic and political changes, catastrophes, and other trigger events. Clouds limit the utility of optical satellite data to monitor cropland abandonment in highly fragmented mountain agricultural landscapes of tropical and subtropical regions, including the south of China. Taking Nanjing County of China as an example, we developed a novel approach by utilizing multisource satellite (Landsat and Sentinel-2) imagery to map multiple trajectories of cropland abandonment (transitioning from cropland to grassland, shrubs and forest) in subtropical mountainous landscapes. Then, we employed a redundancy analysis (RDA) to identify the spatial association of cropland abandonment considering agricultural productivity, physiography, locational characteristics and economic factors. Results indicate the great suitability of harmonized Landsat 8 and Sentinel-2 images to distinguish multiple trajectories of cropland abandonment in subtropical mountainous areas. Our framework of mapping cropland abandonment resulted in good producer's (78.2%) and user's (81.3%) accuracies. The statistical analysis showed 31.85% of croplands cultivated in 2000 were abandoned by 2018, and more than a quarter of townships experienced cropland abandonment with high abandoned rates (>38%). Cropland abandonment mainly occurred in relatively unfavorable areas for agricultural production, for instance with a slope above 6°. Slope and the proximity to the nearest settlement explained 65.4% and 8.1% of the variation of cropland abandonment at the township level, respectively. The developed approaches on both mapping cropland abandonment and modeling determinants can be highly relevant to monitor multiple trajectories of cropland abandonment and ascribe their determinants not only in mountainous China but also elsewhere and thus promote the formulation of land-use policies that aim to steer cropland abandonment. • Multisource satellite images helped to map patterns of cropland abandonment. • We revealed multiple trajectories of cropland abandonment. • Cropland abandonment was common in the studied mountainous area. • Terrain and location characteristics determined patterns of cropland abandonment. [ABSTRACT FROM AUTHOR]

Background: Lacewings (insect order Neuroptera), known in the fossil record since the Early Permian, were most diverse in the Mesozoic. A dramatic variety of forms ranged in that time from large butterfly-like Kalligrammatidae to minute two- winged Dipteromantispidae. Principal Findings: We describe the intriguing new neuropteran family Parakseneuridae fam. nov. with three new genera and 15 new species from the Middle Jurassic of Daohugou (Inner Mongolia, China) and the Early/Middle Jurassic of Sai-Sagul (Kyrgyzstan): Parakseneura undula gen. et sp. nov., P. albomacula gen. et sp. nov., P. curvivenis gen. et sp. nov., P. nigromacula gen. et sp. nov., P. nigrolinea gen. et sp. nov., P. albadelta gen. et sp. nov., P. cavomaculata gen. et sp. nov., P. inflata gen. et sp. nov., P. metallica gen. et sp. nov., P. emarginata gen. et sp. nov., P. directa gen. et sp. nov., Pseudorapisma jurassicum gen. et sp. nov., P. angustipenne gen. et sp. nov., P. maculatum gen. et sp. nov. (Daohugou); Shuraboneura ovata gen. et sp. nov. (Sai-Sagul). The family comprises large neuropterans with most primitive wing venation in the order indicated by the presence of ScA and AA1+2, and the dichotomous branching of MP, CuA, CuP, AA3+4, AP1+2. The phylogenetic position of Parakseneuridae was investigated using a phylogenetic analysis of morphological scoring for 33 families of extinct and extant Neuropterida combined with DNA sequence data for representatives of all extant families. Parakseneuridae were recovered in a clade with Osmylopsychopidae, Prohemerobiidae, and Ithonidae. Conclusions/Significance: The presence of the presumed AA1+2 in wings of Parakseneuridae is a unique plesiomorphic condition hitherto unknown in Neuropterida, the clade comprising Neuroptera, Megaloptera, Raphidioptera. The relative uncertainty of phylogenetic position of Parakseneuridae and the majority of other families of Neuroptera reflects deficient paleontological data, especially from critical important periods for the order, earliest Triassic and latest Triassic/earliest Jurassic. [ABSTRACT FROM AUTHOR]

The article discusses the Aetheogrammatidae has a small family of extinct Neuroptera, comprises six species in five genera, described from the Middle Jurassic to the Lower Cretaceous of China. Topics include no information has available on the mouthpart morphology of Aetheogrammatidae; and the holotype has housed in Shandong Tianyu Museum of Nature.

The newly discovered archival documents point toward the need to reexamine some basic assumptions regarding the Chinese Communist Party's (CCP) relationships with Moscow. The history of the CCP in the 1930s and 1940s can only be understood if we pay attention to the unchanging ideological and, to a significant degree, political dependence, of CCP leaders on Moscow. Contrary to the conventional Western beliefs, the CCP even under Mao Zedong did not cut its apron strings to the Communist International (Comintern) and was not increasingly autonomous and self-directed. The Soviet ideological influence on Chinese Communism remained domineering. The archival documents make clear that starting from the late 1920s and early 1930s Moscow actively assisted the rise of Mao. Moreover, as improbable as it may seem, Moscow was responsible for initiating the cult of Mao. It was Stalin who made his decisive choice in favor of Mao and it was the Comintern General Secretary Georgii Dimitrov who conveyed this decision to the CCP. In other words, Mao owed his rise to Moscow and, in particular, to Stalin, the Kremlin dictator. [ABSTRACT FROM AUTHOR]

• Farmland abandonment and recultivation due to urbanization was reconstructed with detailed time-series. • Urbanization went hand-in-hand with farmland abandonment. • Abandonment followed by a quick conversion to other land uses. • Locational and socio-economic factors crucially determined farmland abandonment patterns. Urbanization often results in agricultural expansion but can also lead to farmland abandonment. However, it remains unclear about the extent, exact timing and determinants of farmland abandonment in response to ongoing urbanization. Using the example of China's Sunan economic region, we present the spatiotemporal trajectories of farmland abandonment and recultivation from 2001 to 2018. We classified Landsat satellite image time-series with a regression trees classifier in Google Earth Engine (GEE). Further, we analyzed the spatiotemporal patterns and rates of farmland abandonment and recultivation. Spatially-explicit logistic regressions were applied to explore the determinants of farmland abandonment in space and time. Our results show widespread farmland abandonment: approximately 232,700 ha of farmland had ever been abandoned from 2001 to 2018, with the highest annual abandonment rate (8.5%) in 2017. Approximately 66,200 ha of abandoned fields were later recultivated, with the maximum recultivated area (13,600 ha) in 2018. Approximately 92% of abandoned fields were later recultivated or reused as the impervious surface within two years of the first detection of abandonment, suggesting more rapid land transformation. The regressions reveal that locational and socio-economic factors determined farmland abandonment patterns. Specifically, a higher likelihood of farmland abandonment was statistically associated with an increased distance from the nearest settlements; the significantly positive relationship between ' Non-agricultural GDP ' and farmland abandonment strengthened over time. In contrast, a lower likelihood of farmland abandonment was observed in areas with more cash crops. The statistical results may extend the application of the Ricardian comparative advantage theory along with Alonso's bid rent theory to explain and predict abandonment patterns in response to ongoing urbanization. Our study is the first attempt in China to apply 30-m Landsat imageries to reconstruct abandonment patterns over long time-series. The findings provide important insights into adjusting land-management practices for preventing farmland abandonment due to urbanization. [ABSTRACT FROM AUTHOR]

Monitoring spatio-temporal changes in winter wheat planting areas is of high importance for the evaluation of food security. This is particularly the case in China, having the world's largest population and experiencing rapid urban expansion, concurrently, it puts high pressure on food demands and the availability of arable land. The relatively high spatial resolution of Landsat is required to resolve the historical mapping of smallholder wheat fields in China. However, accurate Landsat-based mapping of winter wheat planting dynamics over recent decades have not been conducted for China, or anywhere else globally. Based on all available Landsat TM/ETM+/OLI images (~28,826 tiles) using Google Earth Engine (GEE) cloud computing and a Random Forest machine-learning classifier, we analyzed spatio-temporal dynamics in winter wheat planting areas during 1999–2019 in the North China Plain (NCP). We applied a median value of 30-day sliding windows to fill in potential data gaps in the available Landsat images, and six EVI-based phenological features were then extracted to discriminate winter wheat from other land cover types. Reference data for training and validation were extracted from high-resolution imagery available via Google Earth™ online mapping service, Sentinel-2 and Landsat imagery. We ran a sensitivity analysis to derive the optimal training sample class ratio (β = 1.8) accounting for the unbalanced distribution of land-cover types. We mapped winter wheat planting areas for 1999–2019 with overall accuracies ranging from 82% to 99% and the user's/producer's accuracies of winter wheat range between 90% and 99%. We observed an overall increase in winter wheat planting areas of 1.42 × 106 ha in the NCP as compared to the year 2000, with a significant increase in the Shandong and Hebei provinces (p < 0.05). This result contrasts the general discourse suggesting a decline in croplands (e.g., rapid urbanization) and climate change-induced unfavorable cropping conditions in the NCP. This suggests adjustments of the winter wheat planting area over time to satisfy wheat supply in relation to food security. This study highlights the application of Landsat images through GEE in documenting spatio-temporal dynamics of winter wheat planting areas for adequate management of cropping systems and assessing food security in China. [ABSTRACT FROM AUTHOR]

Winter wheat is one of the major cereal crops in China. The spatial distribution of winter wheat planting areas is closely related to food security; however, mapping winter wheat with time-series finer spatial resolution satellite images across large areas is challenging. This paper explores the potential of combining temporally aggregated Landsat-8 OLI and Sentinel-2 MSI data available via the Google Earth Engine (GEE) platform for mapping winter wheat in Shandong Province, China. First, six phenological median composites of Landsat-8 OLI and Sentinel-2 MSI reflectance measures were generated by a temporal aggregation technique according to the winter wheat phenological calendar, which covered seedling, tillering, over-wintering, reviving, jointing-heading and maturing phases, respectively. Then, Random Forest (RF) classifier was used to classify multi-temporal composites but also mono-temporal winter wheat development phases and mono-sensor data. The results showed that winter wheat could be classified with an overall accuracy of 93.4% and F1 measure (the harmonic mean of producer's and user's accuracy) of 0.97 with temporally aggregated Landsat-8 and Sentinel-2 data were combined. As our results also revealed, it was always good to classify multi-temporal images compared to mono-temporal imagery (the overall accuracy dropped from 93.4% to as low as 76.4%). It was also good to classify Landsat-8 OLI and Sentinel-2 MSI imagery combined instead of classifying them individually. The analysis showed among the mono-temporal winter wheat development phases that the maturing phase's and reviving phase's data were more important than the data for other mono-temporal winter wheat development phases. In sum, this study confirmed the importance of using temporally aggregated Landsat-8 OLI and Sentinel-2 MSI data combined and identified key winter wheat development phases for accurate winter wheat classification. These results can be useful to benefit on freely available optical satellite data (Landsat-8 OLI and Sentinel-2 MSI) and prioritize key winter wheat development phases for accurate mapping winter wheat planting areas across China and elsewhere. [ABSTRACT FROM AUTHOR]

• The effects of building density on LST (K) were more significant in areas with dry climates compared to humid climates. • Precipitation was the dominant factor controlling spatial variation of K. • The K-values of northern cities were positively correlated with the areas of water bodies. • Climate-adapted urban planning should emphasize the spatial variance and different determinants of K. The effects of building density on land surface temperature (LST) and its spatial patterns remain poorly understood over large areas. Using Landsat 8 satellite imagery, we quantified the effects of building density on land surface temperature (K) across 21 cities in China and analysed their spatial patterns, possible factors, and mechanisms. Results showed that the effects of building density on LST were more significant in areas with dry climates compared to humid climates. The spatial variability in the effects of building density on LST was closely related to climate conditions, soil type, and vegetation. The results from stepwise regression analysis showed that precipitation (climate) controlled the spatial variability, indicating that there is a complex mechanism underlying these potential factors. Furthermore, the results from climatic zoning statistics revealed that the K-values of northern Chinese cities were positively correlated with the areas of local water bodies. However, the K-values of southern Chinese cities were significantly and positively correlated with the mean annual temperature and aridity and were negatively correlated with population density. Stepwise regression results further indicated that the mean annual temperature may be the most influential factor for southern cities. These results highlight the spatial variance and different determinants of K and suggest that climate-adapted urban design and planning standards are needed in different climate zones. [ABSTRACT FROM AUTHOR]

Research on the mineralogical and geochemical characteristics of altered end-Guadalupian basaltic volcanoclastic rocks can increase the understanding of the alteration history of the overlying stratabound Nb(Ta)-Zr(Hf)-REY-Ga mineralization in the Late Permian coal-bearing sequences. In this paper, based on petrographic observations in addition to XRD, XRF, and ICP-MS analyses, we present and discuss in detail the relationships between primary and secondary minerals and outline the distribution of major and trace element chemistry in the middle/Late Permian basaltic volcaniclastics from the ELIP's zone, western Guizhou, southwest China. The primary clastic suite consists of plagioclase-group minerals, clinopyroxenes, feldspathoids, spinels, and basaltic glasses. Fragments of mafic and, less commonly, felsic and alkaline volcanic rocks are minor components of the studied samples. The alteration products are represented by various chlorite-group minerals (including abundant chamosite), quartz, calcite, albite, analcime, barite, and pyrite, along with relatively minor amounts of titanite, sanidine, magnetite, rutile, and copiapite. The mineralogical and geochemical characteristics of the studied volcaniclastics provide strong evidence correlating them with the high-Ti basalt group, widely distributed within the inner Emeishan large igneous province (ELIP) and coeval rift zone of the middle and outer ELIP. After deposition, the volcaniclastics reacted with complex solutions including heated meteoric waters and were periodically infiltrated by seawater and ascending hydrothermal fluids. As a result, the primary volcanic rocks partly lost alkalis, titanium, silica, and most of the trace elements. These elements, especially the incompatible elements, were probably enriched in the overlying tuffaceous and coal-bearing sequences in the middle and outer ELIP. • Primary and secondary minerals of Emeishan basaltic volcaniclastics were presented. • The volcaniclastics reacted with complex solutions from various sources. • The primary volcanic partly lost alkalis, Ti, Si, and most of the trace elements. • The lost elements were probably enriched in the overlying sediments. [ABSTRACT FROM AUTHOR]

An idea that which zones are the main disturbed areas in mining cities and what are the exact impacts in space concerns re-use and optimal allocation of land. Current research mostly concludes that mining activities impact land use greatly, but there is no definite spatial range of disturbance. To find out the exact range, this paper sets up 12 gradients composed of mineral locations and 11 surrounding gradients with an interval of 3 km. And the “D-C-S” (Disturbance-Continuity- Sustainability) framework was then established to evaluate land use characteristics, including 9 indices in the three layers of disturbance, continuity and sustainability. Here, this paper adopted two approaches − transverse land use profiles and anomalous economic points − to test out the understanding of land use characteristics in mining cities. Our findings show that the areas surrounding mineral locations possibly play a more important role in land use structure and functions, designated to 0–9 km, especially 3–6 km away from mineral locations, where land needs more concerns about optimal allocation for future policy-making to improve the pattern, function and continuity. [ABSTRACT FROM AUTHOR]

Scolytus unicornis, a new species of Scolytus Geoffroy from Yunnan, China, is described and illustrated. Three DNA barcoding sequences (COI, 28S, CAD) of this species are provided. The new species is distinguished from other Asian Scolytus species by the longitudinal wrinkles on the frons only in the area below the eyes, a large median spine situated in the middle of the ventrite 2 base, and female frons with a slightly raised blunt tubercle above the epistoma.

The Pseudepipona herrichii-group includes species of the genus Pseudepipona de Saussure, 1856, subgenus Pseudepipona s. str., without long setae on the gena, the scutum, and the propleura, with the transverse carina of the propodeum forming laterally a tooth or at least a blunt angle, and with the preapical tooth of the male mandible of approximately equal width and length. Taxonomic revision of this group revealed the existence of six species: Pseudepipona aldrichi (Fox, 1892), stat. nov. (= P. herrichii mongolica Giordani Soika, 1970, syn. nov.), P. herrichii (de Saussure, 1856) (= P. herrichii afromontana Gusenleitner, 1977, syn. nov.), P. kozhevnikovi (Kostylev, 1927), P. tingjingliae Fateryga, sp. nov., P. tricarinata (Kokujev, 1913), and P. valentinae Fateryga, sp. nov. A complete diagnosis of the males and females of these species is provided, as is an identification key. Maps detailing the geographic distributions of each species are presented. The available data on their bionomics are also summarized.

The Sinanodonta woodiana species complex includes several cryptic species-level phylogenetic lineages, the taxonomic placement of which is unclear. Here, we present the results of molecular analyses of a Sinanodonta sample from Middle Asia (Uzbekistan). The COI haplotype of the Uzbekistan lineage is similar to those of invasive Sinanodonta populations from Europe, Russia and Myanmar. We show that the non-native Sinanodonta flocks in Europe and Middle Asia originated from a single source population in China. Our results reveal that the Sinanodonta woodiana species complex comprises at least six distinct biological species: S. cf. gibba (=temperate invasive lineage), S. cf. woodiana (=tropical invasive lineage), S. schrenkii (=S. amurensis), S. ovata, S. jourdyi, and S. lucida, and two phylogenetic lineages with uncertain taxonomic names.