Background:During fieldwork conducted in the Bac Yen District of Son La Province, near the Ta Xua Nature Reserve, a representative of a previously never registered genus and species of rodent in Vietnam, the Yunnan field mouse (A. ilex O. Thomas, 1922), was discovered. New information:This finding significantly expands our knowledge of the distribution of Apodemus species in northeastern Indochina. Morphological and genetic analysis of the specimen ruled out accidental introduction and established that the Vietnamese population is natural and belongs to the eastern phylogenetic branch of this species, which also inhabits the southern Yunnan-Guizhou Plateau, as well as the upper reaches of the Mekong, Hong Ha, and Da Rivers. Thus, the list of rodent species and genera in Vietnam has been expanded with a new species. Data on the species' geographic distribution across its range are also provided.

We surveyed the distribution of small terrestrial mammals along the Da (Black) River in the Bac Yen district, Son La province, Vietnam. We recorded 21 species in the area. Species identifications were carried out using morphological and genetic methods in accordance with up-to-date taxonomy. The Da River is traditionally considered a zoogeographic boundary dividing different biogeographic regions in northern Vietnam. Our study was aimed at testing whether it can really be considered as such. Based on the observed distributions, we conclude that the water course is not the distribution boundary for 14 species out of 21 found in the area. Out of the seven remaining species, only those which are associated with the Chinese mountain-forest faunal complex demonstrate their southern boundary along the Da River. Thus, it is unjustified to consider this river as a biogeographic boundary for mammals.

The paper presents novel findings of little-known species of rodents, the blind tree mice Typhlomys in Son La Province, Vietnam, with the first morphological and genetic characterisation and taxonomical description of the new species, T. taxuansis. The study also summarises all the data available on this genus species distribution, museum collections and notes on its taxonomy, which are important to establish the proper conservation status of the species. An exhaustive map of the findings is provided, along with a refined taxonomic key for all six currently morphologically characterised species of the genus. It is shown that, based on the data available to date, the genus is still far from complete. Most species, apparently, do not need a special conservation measure; their status may be established as Least Concerns and Near Threatened (B1a+2a) and the current population trend is stable (IUCN). The paper introduced innovative findings regarding lesser-known rodents, the blind tree mice Typhlomys in Son La Province, Vietnam, along with the primary morphological and genetic identification and taxonomic explanation of the novel species T. taxuansis.

We studied chigger and gamasid mite loads on small mammals during the dry season in Vietnam and used both our field data and museum collections to estimate the influence of environmental factors on mite abundance and prevalence. Generalized linear (mixed effect) models were used to analyze the data. We examined 1,239 small mammal individuals, which were obtained from field expeditions and museum collections belonging to 59 species. In different localities, Rattus Fischer (Rodentia: Muridae), Niviventer Marshall (Rodentia: Muridae), and Maxomys Sody (Rodentia: Muridae) were the most common animals captured. The prevalence of chigger and gamasid mites in our expedition data was high: 72% and 62%, respectively. We found differences in the abundance of chigger mites between different populations of the same species of small mammals. Season and locality were the main factors that influenced chigger mite abundance and prevalence. The best model that predicted the abundance and prevalence of chigger mites included geography (province) as a predictor and host species and season as random effects. For the first time, we analyzed factors connected with climate and weather affecting chigger mites of small mammals in Vietnam.

The paper presented novel findings of little-known species of rodents the Tonkin limestone rat Tonkinomys daovantieni in Cao Bang Province, Vietnam with its morphological and genetic characterisation. The study summarises data on the distribution of this data deficient species, available museum collections, genetic samples, information on its taxonomy and ecology, important to establish the proper conservation status of the species. An exhaustive map of the findings is provided. It is shown that, based on the data currently available, the species does not require taxonomic revision and also, apparently, does not need a special conservation measure; its status may be established to date as Near Threatened B1a+2a and the current population trend - Stable, IUCN.

The study of chigger mites of Vietnam is based on the material collected during fieldworks in 2011–2019 and examination of small mammal samples deposited in museum collections. A total 59 small mammals species were examined (49 species of Rodentia, 8 species of Eulipotyphla, and 2 species of Scandentia). On them, 79 species of chigger mites were collected, of which 44 species are recorded in Vietnam for the first time. Thus, the list of chigger mite species reported in Vietnam has been extended to 122 species belonging to 16 genera and 3 subfamilies. Most recorded species belong to the genera Leptotrombidium and Walchia. New hosts have been recorded for 48 trombiculid species. The study showed that the diversity of trombiculids of various regions of Vietnam has been studied unevenly.

Composting, or controlled organic decomposition, is one of the most important ways to utilize human waste (faeces) on water shortaged regions and cold climate conditions. However, the adding a thermophilic microbial agent on the human faeces composting process was limited because of the low efficiency and composting activity of inoculant under cold climate conditions. This research was performed to evaluate the effect of the psychrotrophic bacteria and thermophilic actinomycetes consortium inoculation, as a microbial inoculant during human faeces composting under low temperature condition (15–20°C) in Northern Vietnam. Mixtures of human faeces and sawdust were inoculated with the psychrotrophic Bacillus consortium (PBC), thermophilic Streptomyces consortium (TAC), and mixed psychrotrophic-thermophilic microbial consortium (PTMC) agents, the ambient temperature at initial composting phase was within 15–20°C. Sterile water used as a control (CK). The results showed that the start of composting process clearly promoted by inoculation with PBC or PTMC as indicated by the quick changes of physicochemical parameters (the temperature, pH, C/N ratio, activity of cellulase, etc.). In the PTMC-inoculated compost piles, temperatures reached the thermophilic stage (over 50°C) and run 5–10 days faster than piles inoculated with TAC, PBC or in control. In addition, compost maturity was promoted by inoculation with TAC or PTMC by a longer thermophilic phase and a greater reduced carbon-nitrogen ratio. Meanwhile, inoculation with PTMC agent in the initial phase favored the composting process by setting up of sufficiently impactful microbial population. The highest thermophilic temperature of 56.9°C increased cellulase activity in the maturity phase and promoted the maturity of composting in general. Accordingly, this is first research on promoting effects of psychrotrophic-thermophilic microbial consortium (PTMC) agents inoculation on human faeces decomposition under cold climate conditions.

Open access to occurrence records in a standardised format has strong potential applications for many kinds of ecological research and bioresources management, including the assessment of invasion risks, formulation of nature protection, biomedical and management plans in the context of global climate and land-use changes both in the short and long perspective. The accumulation and aggregation of data on the occurrence records of small mammals are relevant for the study of biogeography and for ecological surveys including construction of the spatial distribution and ecological niche modelling of species ' distributions in the context of global climate change. The author has created a dataset of 2408 rodents and tree shrews occurrence records from Vietnam, collected from November 2007 to May 2022. A number of zoologist colleagues also provided genetic samples. A considerable part of these data has been published previously in a number of papers; however, most of these data have yet to be presented. These records cover a significant part of the range of many rodent species in Southeast Asia and provide new data on their distribution. The data were obtained during a number of different field expeditions, where some animals were caught by the author and some were provided by other researchers, resulting in different accuracy levels of geographic coordinates and altitude estimates may range from 10 to 1000 metres in area and from 1 to 100 metres for elevation. A number of samples were genetically examined to avoid inconsistencies with the taxonomic identification. With the help of colleagues, the author created a set of georeferenced occurrence records, adapted to the controlled vocabulary of Darwin Core format datasets, removed duplicates and standardised the format of records using commonly-used unified data structure. This paper presents the resulting dataset of rodents (mostly of Muridae and Sciuridae) along with other small terrestrial species (Scandentia Tupaidae) occurrence records in the territory of Vietnam and Laos.Much of the distribution data are currently available as open source GBIF databases and potentially may be combined into a united framework for better data resolution. The dataset presented here combines occurrence records of many species over a significant part of their recent natural range, in Vietnam and Laos. The author presents a validated and comprehensive dataset of rodents' occurrence records, based on genetic samples collection compiled during 15 years working in Vietnam (from 2007 to date). Prior to this project, a considerable part of the information about Vietnamese rodents was not available to a wide range of researchers to use these spatial data for analyses by modern methods, for example, for analysis based on geographic information systems (GIS technologies). This dataset now is available for any researchers who use the data format prepared in accordance with Darwin Core standards.For different countries of Southeast Asia and beyond, there are a lot of additional occurrence records for a number of species listed here which may be combined, but a considerable part of them is still scattered over a number of separate literary sources, while another is still presented as maps, field notes and huge amount of museum zoological collections records. The final set was created by a combination of species occurrence records and uniform data structure with verification of the samples' geographic coordinates. Most samples were genetically or/and morphologically verified for correct taxonomical identification, because the most part of the samples presented was carefully investigated by the author himself, both for morphology and genetic attribution. Therefore, the dataset expands the available information on the spatial and temporal distribution of a number of small mammals’ species in Southeast Asia. All original notes and geographical localities were carefully checked and any duplicate and erroneous records have been removed from the final dataset.To the date of publication of these data, the GBIF database https://www.gbif.org contained 1408 rodent occurrence records from Vietnam (Fig. 1) along with 240 Scandentia records (Fig. 2), primarily the data on museum materials, including four large collections, such as the Field Museum of Natural History (Zoology) Mammal Collection (646 samples), Australian National Wildlife Collection provider for OZCAM (537), MVZ Mammal Collection Arctos (109), Museum of Comparative Zoology, Harvard University (69) and six other minor collections comprising single specimens.Actually, as for the small terrestrial mammals, Vietnam remains one of the least representative regions in Southeast Asia. Here, we present new data containing 2408 occurrence records, including 2237 rodent records, along with 171 Scandentia ones (Fig. 3). Thus, the data significantly expand our knowledge about actual ranges of a number of species, including rare and endangered ones.

Based on new molecular data for mitochondrial ( Cyt b ) and nuclear ( IRBP , RAG1 ) genes, as well as an extensive analysis of morphological material, we accessed actual species taxonomy and relationships among Asian red-cheeked squirrels Dremomys distributed in eastern Indochina and southern China. Phylogenetic analyses demonstrated that Asian red-cheeked squirrels, which are currently attributed to D. rufigenis , are not homogenic but instead consisted of two independent species-level clades—northern and south-central. The latter clade was additionally subdivided into two highly divergent clades based on Cyt b gene phylogeny. In spite of multidimensional statistics approach applied (PCA) only minor cranial differences were found between populations of study what lay a basis to treat it as cryptic species. Based on our findings, red-cheeked squirrels inhabit northern Vietnam and southern China, which are usually attributed to D. rufigenis , should be treated as distinct genetic species D. ornatus Thomas, 1914. In ones turn, based on its peculiar external morphology we can attribute the specimens from southern and central Vietnam to D. rufigenis proper and treat them as D. rufigenis fuscus Bonhote, 1907 and D. r. laomache Bonhote, 1921, respectively.

The study combines available data on species distribution in eastern Indochina to investigate the phylogeographical genetic and morphological diversity of tree rats (Chiromyscus, Rodentia, Muridae) and to specify their natural ranges. We examined the diversity and distribution of tree rats over its range, based on recent molecular data for mitochondrial (Cyt b, COI) and nuclear (IRBP, RAG1 and GHR) genes. The study presents the most complete and up-to-date data on the distribution and phylogeography of the genus in eastern Indochina. As revealed by mitochondrial genes, C. langbianis splits into at least four coherent geographically-distributed clades, whereas C. thomasi and C. chiropus form two distinctive mitochondrial clades each. Chiromyscus langbianis and C. chiropus show significant inconsistency in nuclear genes, whereas C. thomasi shows the same segregation pattern as can be traced by mitochondrial markers. The Northern and Southern phylogroups of C. thomasi appear to be distributed sympatrically with northern phylogroups of C. langbianis in most parts of eastern Indochina. The mitochondrial clades discovered are geographically subdivided and divergent enough to suspect independent subspecies within C. langbianis and C. thomasi. However, due to the insufficiency of obvious morphological traits, a formal description is not carried out here. The processes of recent fauna formation, species distribution patterns, dispersion routes and possible natural history in Indochina are discussed.

Background & objectives: Rodents are important reservoir hosts for several zoonotic pathogens such as Rickettsia, Leptospira and Bartonella. Studies on the prevalence of zoonotic pathogens in Vietnam are data deficient, and there is a scarcity of data on multiple co-infections of zoonotic pathogens to date. This study examined the prevalence of Rickettsia spp., Leptospira spp., and Bartonella spp. and the co-infection of these pathogens in rodents captured in three provinces of northern Vietnam - Ha Giang, Lao Cai and Cao Bang. Methods: In total, 133 rodents of 25 species were screened for pathogen prevalence by real-time PCR. Results: Very high infection rates were found for each pathogen, with 42 of 133 rodents (31.6%) positive for Bartonella and 33 of 133 (24.8%) positive for Rickettsia (5.3% were positive for Rickettsia typhi, and 19.5% were infected with Rickettsia spotted fever group). Additionally, 24 rodents (18%) were positive for Leptospira. Double infection among these three pathogens was found in 26 of 133 rodents (18.8%), with the highest dual infection rates for Rickettsia and Bartonella co-infection (40%) and Leptospira and Bartonella co-infection (up to 40%), followed by Rickettsia and Leptospira co-infection (20% of animals investigated). One case of triple infection was documented for a house rat (Rattus cf. rattus species group) trapped in Ha Giang province. Interpretation & conclusion: Our survey indicates that rodents in northern Vietnam may host multiple zoonotic pathogens simultaneously; thus, rodents contribute significantly to the increased risk of transmission of multiple zoonotic infections from animals to humans.

The present study was aimed to determine the potential cultivated lands for rice crop production in Vietnam. Analytic Hierarchy Process (AHP) and the Technique for Order of Preference by Similarity to Ideal Solution (TQPSIS) were employed in order to analyze the structure of an ideal solution in agriculture that focuses mainly on environmental, economic, and social sustainability. A final ranking of alternative development solutions was also accomplished. Three major factors were taken into consideration during the process, including the economics, social concerns, and the environment, in order to develop a sustainable plan for rice and other grain crops in the future. The obtained results demonstrate that the area under investigation in Quang Tri province, which encompasses 192.49 km2 of land area, was extremely conducive to growing rice crops, with the majority of the arable lands suitable for cultivating rice varieties concentrated in Trieu Long District (63.14 km2) and Hai Lang District (56.87 km2). The main findings of the present work indicated that, it can link decision makers with the influencing variables of rice crop growing utilizing a hybrid method that can be successfully used based on GIS technique. To expand production, chemical soil characteristics and agricultural development strategies should be investigated further, particularly in the studied areas with greater success potential.