Qinghai-Tibet Plateau Of China Research Articles

Lasiopodomys fuscus as an important intermediate host for Echinococcus multilocularis: isolation and phylogenetic identification of the parasite

BackgroundEchinococcus multilocularis causes alveolar echinococcosis (AE) and is widely prevalent in Qinghai Province, China, where a number of different species have been identified as hosts. However, limited information is available on the Qinghai vole (Lasiopodomys fuscus), which is hyper endemic to Qinghai Province and may represent a potential intermediate host of E. multilocularis. Thus, L. fuscus could contribute to the endemicity of AE in the area.MethodsFifty Qinghai voles were captured from Jigzhi County in Qinghai Province for the clinical identification of E. multilocularis infection via anatomical examination. Hydatid fluid was collected from vesicles of the livers in suspected voles and subjected to a microscopic examination and PCR assay based on the barcoding gene of cox 1. PCR-amplified segments were sequenced for a phylogenetic analysis. E. multilocularis-infected Qinghai voles were morphologically identified and subjected to a phylogenetic analysis to confirm their identities.ResultsSeventeen of the 50 Qinghai voles had E. multilocularis-infection-like vesicles in their livers. Eleven out of the 17 Qinghai voles presented E. multilocularis infection, which was detected by PCR and sequencing. The phylogenetic analysis showed that all 11 positive samples belonged to the E. multilocularis Asian genotype. A morphological identification and phylogenetic analysis of the E. multilocularis-infected Qinghai voles confirmed that all captured animals were L. fuscus.ConclusionsL. fuscus can be infected with E. multilocularis and plays a potential role in the life cycle and epidemiology of E. multilocularis in the Qinghai-Tibetan Plateau of China.

Signals of pollution revealed by trace elements in recent snow from mountain glaciers at the Qinghai–Tibetan plateau

In order to extract pollution signal of trace elements (TEs) in glacier snow at the Qinghai-Tibetan plateau of China by human activities, concentrations of 18 TEs (Al, Ti, Fe, Rb, Sr, Ba, V, Cr, Mn, Li, Cu, Co, Mo, Cs, Sb, Pb, Tl, and U), 14 rare earth elements (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu), Y and Th in digested snow samples from five glaciers in April–May 2013 before monsoon season were measured. Results shown that higher TEs concentrations were found in glaciers at the northern plateau while lower concentrations in glaciers at the central and southern plateau. Discussion revealed that EF values calculated from elements with mass fraction <30% such as Ti and Al, etc in traditional acid leached samples, will overestimate at least 4.6 times the contribution of other sources than dust for TEs such as Sb, Sr, As, Cu and Pb etc. Analysis indicated that most TEs mainly originated from dust sources, whereas Pb, Cu, Mo and Sb showed occasionally significant contributions from polluted sources in three snow pits and the GRHK surface snow samples. The pollution probably originated from mining and smelting, road transport emissions on the plateau and some regions outside of the plateau. Dust provenance tracing results based on REEs indicated that Taklimakan Desert, Qaidam Basin, and Tibetan surface soil were the potential dust sources for the studied glaciers, while the Indian Thar Desert was an occasional dust sources for YZF,XDKMD and GRHK snow samples.

A simplified method for predicting the penetration distance of cementing slurry in gas hydrate reservoirs around wellbore

The permafrost region in the Qinghai-Tibet Plateau of China is abundant in natural gas hydrate (NGH) resources. In this region, there is a great probability of meeting gas hydrate when conducting conventional oil and gas well cementation operations. Because of the relatively developed fractures and not very high pore pressure (usually 3.5–3.6 MPa) in the gas hydrate reservoirs in this area, it is easy for the cementing slurry to penetrate into the gas hydrate reservoirs under the pressure difference during cementing process, undergo hydration and release heat, thus causing hydrate dissociation and cementing quality reduction or even failure. Therefore, it is necessary to first determine the penetration distance of the cementing slurry in the gas hydrate reservoirs to evaluate the effect of hydration of the cementing slurry on the hydrate stability in the reservoirs. In this paper, theoretical and experimental methods for determining the penetration distance value of cementing slurry were established for the first time. The permafrost layer in the Muli area of the Qinghai-Tibet Plateau was selected as the research object and the proposed computational model was verified by using low-density cementing slurry and common cementing process experiments. The results show that the penetration distance calculated by the established computational model is in good agreement with that measured in the experiment, and the computational model can provide technical support for the cementing process design in gas hydrate occurrence area.

Identification and evaluation of Aspergillus tubingensis as a potential biocontrol agent against grey mould on tomato

Grey mould of tomato caused by Botrytis cinerea is a highly damaging disease worldwide. This study was aimed at identifying fungal strain QF05, which was isolated from the sandy soil collected in the Qinghai-Tibet Plateau in China and to evaluate its biocontrol potential on grey mould and growth promotion effect on tomato plants. On the basis of morphological observation and a multigene phylogeny based on the ITS, β-tubulin and calmodulin genes, QF05 was identified as Aspergillus tubingensis. An in vitro dual culture test indicated obvious antagonistic activity by strain QF05 against B. cinerea. Strain QF05 distinctly reduced grey mould in assays on tomato fruits and plants. Treatments with the culture filtrate of strain QF05 and a tenfold dilution of the filtrate gave disease biocontrol efficacy of 34.5 and 31.0% on tomato plants, respectively. QF05 also promoted seed germination and plant growth of tomato. Length and total fresh and dry mass of tomato plants were all significantly increased by 17.8, 25.7 and 56.8%, respectively, after treatment with the tenfold dilution of the culture filtrate. QF05 also had positive biocontrol attributes such as indoleacetic acid and siderophore production, phosphate solubilization, and rhizosphere colonization. All these results indicated the good performance of A. tubingensis QF05 for the biocontrol of tomato grey mould and growth promotion of tomato plants.

Effect of snowpack on the soil bacteria of alpine meadows in the Qinghai-Tibetan Plateau of China

Global climate change is accompanied by changes in the amounts of ice and snow. These changes have both a direct effect on the plant community structure, primary productivity and carbon cycle and an indirect influence on the belowground ecosystem. However, the effects of changes in snowpack on the soil environment and belowground ecological processes, particularly in soil microbial communities are still poorly understood in alpine meadows. We conducted a field study of controlled snowpack in the eastern margin of the Tibetan Plateau, where five treatments were set up, named as S0, S1, S2, S3, and S4 (S1: the amount of a natural snowpack; S2, S3, and S4 were twofold, threefold, and fourfold of S1, respectively; and S0: completely removed snow). Soil physicochemical properties, soil community structure and diversity measured by 16S rRNA gene amplicons were studied. The results indicated that 1) as snowpack increased, the average soil temperature decreased, but soil moisture and soil compaction increased; 2) soil chemical properties (pH, available nitrogen, available potassium, available phosphorus, total nitrogen, total potassium, total phosphorus and total soil organic carbon) all changed as snowpack changed; and 3) increasing snowpack led to a decrease in the relative abundance of Acidobacteria, but Bacteroidetes and Actinobacteria did not decline in response to increasing snowpack. In summary, these results showed that soil bacterial communities are sensitive to changes in snowpack in alpine meadows.

Molecular epidemiology and characterization of bovine leukemia virus in domestic yaks (Bos grunniens) on the Qinghai-Tibet Plateau, China.

Bovine leukemia virus (BLV) is a member of the genus Deltaretrovirus of the family Retroviridae and cause a chronic lymphosarcoma, which is extensive in cattle. In yaks (Bos grunniens), the distribution, strains and genetic characteristics of BLV have rarely been studied. The aim of our study was to investigate BLV infections in domestic yaks and determine the genetic variability of BLV circulating in a region of the Qinghai Tibet Plateau, China. Blood samples were collected from 798 yaks, which were from different farms from Gansu, Qinghai and Sichuan provinces surrounding the Qinghai-Tibet Plateau. Nested PCR targeting BLV long terminal repeats was used to detect the BLV provirus. The highest prevalence of BLV infection was in Gansu province, where it was 18.93% (39/206) in white yaks from Tianzhu City and 19.14% (31/162) in black yaks from Gannan City. In Qinghai and Sichuan provinces, the prevalence of BLV in black yaks was 14.83% (35/236) and 14.94% (29/194), respectively. The prevalence of BLV was not significantly different in yaks up to one year old than in older animals. Phylogenetic analysis was performed using 16 different env-gp51 (497-bp) gene sequences from the three provinces and 71 known BLV strains, which revealed that in both Gansu and Qinghai provinces, genotypes 6 and 10 of the BLV strains were at high levels, whereas only genotype 10 was prevalent in Sichuan Province. Phylogenetic analysis and sequence comparisons revealed 95.7-99.8% sequence identity among the full-length env genes of 16 strains, nearly full-length genome sequences of six BLV strains, and those of the known genotypes 6 and 10 of BLV. This study provides comprehensive information is regarding the widespread infection of domestic yaks with BLV on the Qinghai-Tibet Plateau of China, and shows that at least two BLV genotypes (genotypes 6 and 10) are circulating in this population.

Characterization and phylogenetic analysis of the complete chloroplast genome of Orinus thoroldii (Poaceae)

Orinus thoroldii is an important alpine grass endemic to the western Qinghai-Tibet Plateau in China, which has high ecological and genetic values. Here, we first assembled the complete chloroplast (cp) genome of O. thoroldii based on sequences from Illumina HiSeq4000 platform. We obtained the cp genome with the total length of 134,205 bp. It is a standard quadripartite structure composed of the large (LSC, 79,699 bp) and small (SSC, 12,458 bp) single copy regions separated by a pair of inverted repeats (IRs, 21,024 bp each). The cp genome encodes 136 genes including 81 protein-coding genes, 44 tRNAs genes and eight rRNAs genes. The overall GC content of the cp genome is 38.4%. The phylogenetic analysis indicated that O. thoroldii is sister to Eragrostis tef in Chloridoideae.

Studies of the cryopreservation condition of Gymnocypris przewalskii spermatozoa

The endemic naked carp (Gymnocypris przewalskii Kessler, 1876) plays an important role in the maintenance of the distinctive ecological system of Lake Qinghai at 3.2km altitude on the Qinghai-Tibet Plateau in China. This study aimed to develop a cryopreservation protocol for Gymnocypris przewalskii spermatozoa. Semen was collected from mature individuals during migration and frozen using the liquid nitrogen vapor method. The influence of different cryoprotectants and three extenders on the post-thaw quality of the sperm was analyzed. The highest sperm motility rate and longest motility time after cryopreservation were achieved by combining Ringer’s solution with 15% ethylene glycol (P<0.05). The fertilization rate of this cryopreserved semen was 15.26±4.54%. This study thus provides a valuable method for the cryopreservation of the sperm of this important endangered fish species.

A cave δ18O based 1800-year reconstruction of sediment load and streamflow: The Yellow River source area

Located on the northeast edge of the Qinghai-Tibet Plateau in China, the Yellow River source area (YRSA) is the river's major water source area and therefore it is called “water tower” of the Yellow River. However, the instrumental data are only 50-years, based on which the hydrological response at 100–1000years cannot be understand properly. Although many results of streamflow reconstruction are published, the results of high-resolution suspended sediment load (SSL) reconstruction have not been reported yet. Here we show that the Wanxiang Cave δ18O record (Zhang et al., 2008) can be used to reconstruct the SSL of the YRSA along with the mean annual streamflow, annual maximum discharge and precipitation. Based on the data of the overlapping period (1961–2001) after 5-year moving, calibration equations were established, using regression method. The R of annual stream flow, SSL, maximum discharge and precipitation with 5-year moving δ18O is −0.768, −0.763, −0.692 and −0.803, respectively, at p<0.000001. After validation using Leave-One-Cross Validation method, we reconstructed the 1800-year variations in these variables. Based on statistical analysis, we proved the existence of the following cause-effect chain: the weakened (or strengthened) Asian Summer Monsoon recorded by cave δ18O→increased (or decreased) water vapor to the YRSA→increased (or decreased) precipitation→increased (or decreased) streamflow→increased (or decreased) SSL. These links provide the scientific basis for the paleo-hydrological reconstruction. Over the past 1800years, the Qinghai-Tibet Plateau's water tower effect on the Yellow River showed an overall decreasing trend, with the 5-year moving streamflow decreased at a rate of 4.81 million m3/year. Eight stages of alternative decrease and increase were identified, of which two long continuing decline stages are likely one of the factor that caused the collapse of the Tang and Ming dynasties. The uncertainties that should be considered to improve the model in the future are also discussed.

Euchlorocystis gen. nov. and Densicystis gen. nov., Two New Genera of Oocystaceae Algae from High-altitude Semi-saline Habitat (Trebouxiophyceae, Chlorophyta).

The Oocystaceae family is generally considered to contain common freshwater eukaryotic microalgae, and few are reported living in semi-saline habitats. Our latest ecological survey in Qinghai Lake and Angzicuo Lake, both large, closed, high-altitude, semi-saline lakes located on the Qinghai-Tibet plateau in China, revealed Oocystaceae species as a dominant group among plankton. Since limited knowledge exists about semi-saline species in the Oocystaceae family, a taxonomical study was carried out using morphological and phylogenetic methods. Using this approach, four new strains of Oocystaceae were identified and successfully cultured in the lab. Molecular results correlated with morphological characters and resolved these species into at least three genera. A new genus, Euchlorocystis, with type species Euchlorocystis subsalina, is described here as having the distinctive morphology of multiple pyrenoids per chloroplast among Oocystaceae, and an independent phylogenetic position at the base of the Oocystaceae. Similarly, the genus Densicystis, with type species Densicystis glomerata, is newly proposed here as having a unique colony morphology of dozens or hundreds of little cells tightly embedded in ellipsoid to round mucilage masses. Oocystis marina, originally described from the Baltic Sea, was also identified in Qinghai Lake and Angzicuo Lake and phylogenetically positioned in the semi-saline clade of the Oocystaceae. The result that a marine species was detected in the closed inland lakes implies a further need to reevaluate the origins of these species.

Effects of short-term N addition on soil C fluxes in alpine Sibiraea angustata scrub on the eastern margin of the Qinghai-Tibetan Plateau

Although knowledge of the impact of N enrichment on soil C fluxes is scant, such information is highly critical for estimating the global C budget under elevated N deposition. To quantify the effects of short-term N addition on soil C sequestration in an alpine scrub ecosystem, we conducted a field experiment for Sibiraea angustata scrub on the eastern margin of the Qinghai-Tibetan Plateau in China. We quantified the soil C pool (0–30cm) and C fluxes in litterfall, fine root (<2mm diameter) production (FRP), and soil CO2 emission (heterotrophic respiration, Rh) over four years with four levels of N addition (N0; control, N20; 20, N50; 50, and N100, 100kgNha−1year−1). The results showed that at control plots the total C-input (433±33gCm−2year−1) via FRP (360±34gCm−2year−1) and litterfall (73±1gCm−2year−1) was close to the C-output via Rh (466±5gCm−2year−1), which demonstrates that the S. angustata scrub soil C is at equilibrium status. However, adding N, particularly the N100 treatment, significantly affected the soil C balance; the soil became a C sink (163±46gCm−2year−1) by increasing FRP (+63%) rather than by increasing litterfall (P>0.05) or reducing Rh (P>0.05). As a result, the soil C pool (0–30cm) increased significantly. In conclusion, these results suggest that fine roots play a dominant role in the C balance of an alpine scrub ecosystem due to large C-inputs to the soil. Moreover, short-term high N enrichment causes sequestration of additional atmospheric CO2, largely because of the stimulation of fine root growth rather than increased inputs of aboveground plant litterfall or reductions in soil CO2 emission.

Spatial and temporal change patterns of freeze-thaw erosion in the three-river source region under the stress of climate warming

The three-river source region (TRSR), located in the Qinghai-Tibet Plateau in China, suffers from serious freeze-thaw (FT) erosion in China. Considering the unique eco-environment and the driving factors of the FT process in the TRSR, we introduce the driving force factors of FT erosion (rainfall erosivity and wind field intensity during FT period) and precipitation during the FT period (indicating the phase-changed water content). The objective was to establish an improved evaluation method of FT erosion in the TRSR. The method has good applicability in the study region with an overall precision of 92%. The spatial and temporal changes of FT erosion from 2000 to 2015 are analyzed. Results show that FT erosion is widely distributed in the TRSR, with slight and mild erosion being the most widely distributed, followed by moderate erosion. Among the three sub-regions, the source region of the Yellow River has the slightest erosion intensity, whereas the erosion intensity of the source region of Yangtze River is the most severe. A slight improvement can be observed in the condition of FT erosion over the whole study region from 2000 to 2015. Vegetation coverage is the dominant factor affecting the intensity of FT erosion in the zones with sparse vegetation or bare land, whereas the climate factors play an important role in high vegetation coverage area. Slopes>28° also have a significant effect on the intensity of FT erosion in the zones. The results can provide a scientific basis for the prevention and management of the soil FT erosion in the TRSR.

Rumen prokaryotic communities of ruminants under different feeding paradigms on the Qinghai-Tibetan Plateau

Yak and Tibetan sheep are the major indigenous ruminants on the Qinghai-Tibetan Plateau in China. The aim of this work was to study the differences in ruminal fermentation parameters and rumen prokaryotic community composition between hosts and feeding paradigms. The 16S rRNA genes targeting bacteria and archaea were sequenced using the MiSeq platform. The results showed that the prokaryotic community structure between yak and Tibetan sheep was significantly different (P<0.01). A significant difference in structure was also found between groups of yaks barn fed with a total mixed ration (TMR) and those naturally grazing (NG) (P=0.034), as well as for Tibetan sheep of the two groups (P=0.026). The core prokaryotic populations that existed in the rumen mostly dominated the structure. There was an obvious correlation of the prokaryotic community composition at the phylum and genus levels with the host or the feeding pattern. In addition, Tibetan sheep showed significantly higher yields of volatile fatty acids (VFAs) than yak, as did the NG group compared with the TMR group. In conclusion, both the host and feeding pattern may influence rumen microbial ecology system, with host effects being more important than those of the feeding pattern.

A study of thermal comfort in residential buildings on the Tibetan Plateau, China

Tibet is located on the Qinghai-Tibetan Plateau in China, the highest and largest plateau in the world. It is in the Cold and Severe Cold zones according to the Chinese climatic division for building design and has unique climatic characteristics and traditional cultural background. In order to obtain a comprehensive understanding about the real indoor thermal environment and the residents' thermal comfort status in Tibet, a field investigation of residential buildings was conducted in the Tibetan Alpine region with on-site environmental parameter measurements and a simultaneous survey using a subjective thermal comfort questionnaire. Based on the analysis of the data collected from the field study, the value of the adaptive coefficient λ in the adaptive thermal comfort model aPMV=PMV1+λPMV suitable to the Tibet area has been obtained as −0.34; and thus the acceptable thermal comfort temperature range for residential buildings in this area has been produced. The research findings provide comprehensive knowledge and a useful reference for the development of a design and evaluation standard for indoor thermal environments in the Tibet region.

Predicting the shift of threatened ungulates’ habitats with climate change in Altun Mountain National Nature Reserve of the Northwestern Qinghai-Tibetan Plateau

Climate change has affected the geographic distribution of many species and numerous endemic species with narrow distribution ranges on the Qinghai-Tibetan Plateau of China, one of the biodiversity hotspots and critical eco-regions in the world. Altun Mountain National Nature Reserve is one of the most important refuges for the flagship species and threatened endemic ungulates, Tibetan antelope (Pantholops hodgsoni), wild Tibetan donkey (Equus kiang), and wild yak (Bos mutus). We surveyed the distribution of these three species and their forage plants in the nature reserve between 2012 and 2013. Using the Maxent model, we projected the potential distribution of the Tibetan antelope, wild Tibetan donkey, and wild yak and their forage plants based on the four representative concentration pathways set by the IPCC Fifth Assessment Report for 2070. We generated 36 future model scenarios to assess and reduce the model uncertainties. We found that projected food availability associated with climate niche would be more realistic for ungulates distribution projections under climate change. Our results demonstrated that future climate change would greatly change the habitats of three threatened endemic ungulates and their forage plants. The ranges of climate niche projected for the Tibetan antelope, wild Tibetan donkey, and wild yak would be reduced by 44, 7, and 20%, respectively, with future climate change under representative concentration pathways 2.6 scenario. Among them, the ranges of Tibetan antelope and wild Tibetan donkey would reduce even more under warmer scenarios, but wild yak would be opposite. The projected distribution ranges of forage plants reduced with the climate change in the future. The combined effects of shifting climate niche and food resources would lead to the reduction of habitats for Tibetan antelope, wild Tibetan donkey, and wild yak by 82, 34, and 30% under representative concentration pathways 2.6. However, conditions would be worse for Tibetan antelope and wild Tibetan donkey but better for wild yak under other scenarios. We suggested that future conservation efforts should be focused on improving habitat quality (including food availability) and finding alternative habitats for the three ungulates especially Tibetan antelope and wild Tibetan donkey.

Greenhouse gas emission of pastoralism is lower than combined extensive/intensive livestock husbandry: A case study on the Qinghai-Tibet Plateau of China

The increasing demand of livestock products and production efficiency of livestock husbandry, and restoration of grassland ecosystem have been inducing the rapid transition of livestock husbandry systems from pastoralism into intensive systems. Such transition has been resulted in changes in the greenhouse gas (GHG) emissions, though it is rarely studied, especially in the pastoral area of China. Aimed to address this question, on the Qinghai-Tibet Plateau we selected Chanaihai village as the pastoralism system, and Guinan Grassland Development Limited Company as the combination of extensive and intensive livestock husbandry system, to compare the GHG emission between the two systems using life cycle assessment method. Our results showed that the GHG emission intensity both in per unit of area and per unit of carcass weight in the combined extensive/intensive livestock husbandry were higher than the pastoralism, indicating that the shift into the combined extensive/intensive livestock husbandry system increased the GHG emission. Such results could be attributed to the lower soil carbon uptake and higher GHG emission derived from the external inputs such as seed, diesel, and electricity in the combined extensive/intensive system. These findings demonstrated that the ongoing transition in the pastoral area of Qinghai-Tibet Plateau may be inappropriate under the background of global GHG mitigation. As suggestions, we argued that reduction in the manure combustion and increase in soil carbon uptake could be effective measures to reduce the GHG emission intensity of livestock husbandry.

Streptococcus himalayensis sp. nov., isolated from the respiratory tract of Marmota himalayana.

Five strains of Gram-positive-staining, catalase-negative, coccus-shaped, chain-forming organisms isolated separately from the respiratory tracts of five Marmota himalayana animals in the Qinghai-Tibet Plateau of China were subjected to phenotypic and molecular taxonomic analyses. Comparative analysis of the 16S rRNA gene indicated that these singular organisms represent a new member of the genus Streptococcus, being phylogenetically closest to Streptococcus marmotae DSM 101995T (98.4 % similarity). The groEL, sodA and rpoB sequence analysis showed interspecies similarity values between HTS2T and Streptococcus. marmotae DSM 101995T, its closest phylogenetic relative based on 16S rRNA gene sequences, of 98.2, 78.8 and 93.7 %, respectively. A whole-genome phylogenetic tree built from 82 core genes of genomes from 16 species of the genus Streptococcus validated that HTS2T forms a distinct subline and exhibits specific phylogenetic affinity with S. marmotae. In silico DNA-DNA hybridization of HTS2T showed an estimated DNA reassociation value of 40.5 % with Streptococcus. marmotae DSM 101995T. On the basis of their phenotypic characteristics and phylogenetic findings, it is proposed that the five isolates be classified as representatives of a novel species of the genus Streptococcus, Streptococcus himalayensis sp. nov. The type strain is HTS2T (=DSM 101997T=CGMCC 1.15533T). The genome of Streptococcus himalayensis sp. nov. strain HTS2T contains 2195 genes with a size of 2 275 471 bp and a mean DNA G+C content of 41.3 mol%.

Life cycle of Haemaphysalis tibetensis Hoogstraal, 1965 (Acari: Ixodidae) under laboratory conditions

The tick Haemaphysalis tibetensis is endemic in Qinghai-Tibet plateau of China, and regarded as potential vector of spirochetes and orbivirus. However, knowledge on its life cycle and biological characteristics is meager. Therefore, this paper investigated the life cycle of H. tibetensis under laboratory conditions. Results indicated that, the tick H. tibetensis required a mean duration of 166.7 days to complete the whole cycle, and the average developmental periods of larvae and nymphs were 34.0 days and 41.6 days, respectively. The summation of the prefeeding, feeding and preovipositon periods of females was 23.9 days, and oviposition lasted for 19.4 days. Egg incubation required 47.8 days, which was the longest period in the whole life cycle. Linear regression analysis revealed a highly positive correlation between the weight of the engorged female and the number of the egg mass laid (r=0.91). The reproductive efficiency index and the reproductive fitness index were 5.2 and 4.5, respectively.

Analysis of Draft Genome Sequence of Pseudomonas sp. QTF5 Reveals Its Benzoic Acid Degradation Ability and Heavy Metal Tolerance.

Pseudomonas sp. QTF5 was isolated from the continuous permafrost near the bitumen layers in the Qiangtang basin of Qinghai-Tibetan Plateau in China (5,111 m above sea level). It is psychrotolerant and highly and widely tolerant to heavy metals and has the ability to metabolize benzoic acid and salicylic acid. To gain insight into the genetic basis for its adaptation, we performed whole genome sequencing and analyzed the resistant genes and metabolic pathways. Based on 120 published and annotated genomes representing 31 species in the genus Pseudomonas, in silico genomic DNA-DNA hybridization (<54%) and average nucleotide identity calculation (<94%) revealed that QTF5 is closest to Pseudomonas lini and should be classified into a novel species. This study provides the genetic basis to identify the genes linked to its specific mechanisms for adaptation to extreme environment and application of this microorganism in environmental conservation.

Using fuzzy analytic hierarchy process for spatio-temporal analysis of eco-environmental vulnerability change during 1990–2010 in Sanjiangyuan region, China

Sanjiangyuan region, which located in the north of Qinghai-Tibet Plateau in China, is characterized by an extreme environment and is subject to the impacts of climate change and intense human activities. To protect the eco-environment in Sanjiangyuan, the Sanjiangyuan National Nature Reserve (SNNR) was established in 2000, and an ecological project was initiated in 2005. Comprehensive and quantitative evaluation of the eco-environmental vulnerability (EV) and analysis of the long-term dynamic changes in the region are extremely important for understanding eco-environmental change and assessing protection effectiveness, however rarely found in previous research.The aim of this study is to develop a method to assess EV and analyse the dynamic change in Sanjiangyuan region for years 1990, 2000 and 2010. In the first phase of the study, an integrated evaluation method based on Fuzzy Analytic Hierarchy Process (FAHP) was developed. This phases included:■development of the evaluation hierarchical structure and selection criteria;■data collection and processing;■evaluation criteria normalization;■determination of the related importance of the criteria;■criteria weighting calculation, and;■linear weighted combination.In the second phase of the study, the developed methodology was applied to assess the EV in the Sanjiangyuan region for the years 1990, 2000, and 2010, and to document the dynamic change. In the third phase, a series of integrated regional EV grades were used to analyse the EV change both within and outside of SNNR.The results showed that: 1) EV in the whole Sanjiangyuan region was distributed as a high/low gradient that trends west to east in all three study periods; 2) the dynamic change of EV in Sanjiangyuan region as a whole showed a moderate reduction during 1990–2000, a sizeable and extensive decrease during 2000–2010; and, 3) during the 2000–2010 period, ecological environment change magnitude was significantly better within the Sanjiangyuan National Nature Reserve than for the unprotected areas of the region. The proposed method is relatively easy to implement and could also be applied to other study regions. However, the method could be further improved by reducing some subjective elements.