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Climate change is a significant force influencing catchment hydrological processes, such as baseflow, i.e., the contribution of delayed pathways to streamflow in drought periods and is associated with catchment drought propagation. The Weihe River Basin is a typical arid and semi-arid catchment on the Loess Plateau in northwest China. Baseflow plays a fundamental role in the provision of water and environmental functions at the catchment scale. However, the baseflow variability in the projected climate change is not well understood. In this study, forcing meteorological data were derived from two climate scenarios (RCP4.5 and RCP8.5) of three representative general circulation models (CSIRO-Mk3-6-0, MIROC5, and FGOALSg2) in CMIP5 and then were used as inputs in the Soil and Water Assessment Tool (SWAT) hydrological model to simulate future streamflow. Finally, a well-revised baseflow separation method was implemented to estimate the baseflow to investigate long-term (historical (1960–2012) and future (2010–2054) periods) baseflow variability patterns. We found (1) that baseflow showed a decreasing trend in some simulations of future climatic conditions but not in all scenarios (p < 0.05), (2) that the contribution of baseflow to streamflow (i.e., baseflow index) amounted to approximately 45%, with a slightly increasing trend (p ≤ 0.001), and (3) an increased frequency of severe hydrological drought events in the future (2041–2053) due to baseflows much lower than current annual averages. This study benefits the scientific management of water resources in regional development and provides references for the semi-arid or water-limited catchments. [ABSTRACT FROM AUTHOR]

Plants generally adopt different reproductive strategies to adapt to their environments and increase their fitness. Here, we studied the effects of enclosure cultivation on the reproductive allocation of a wheatgrass species Agropyron mongolicum in the Desert steppes of Northern China. The results showed that: (a) after enclosure cultivation, the height, clump width, coverage, and clump biomass of A. mongolicum significantly increased by 78.96% (p =.040), 63.50% (p =.013), 50.89% (p =.032), and 205.38% (p =.022), respectively, whereas density did not show a significant change (p =.330). (b) Enclosure cultivation significantly affected the biomass of A. mongolicum. Compared with cultivation outside the fence, root, leaf, and spike biomass of A. mongolicum inside the fence significantly increased by 183.52% (p =.020), 334.09% (p =.011), and 381.25% (p =.005), respectively. In addition, root biomass was the highest among the components (38.53 and 13.59 g inside and outside the fence, respectively) and spike biomass was the lowest (6.16 and 1.28 g inside and outside the fence, respectively). (c) Enclosure cultivation affected elemental nutrient allocation and the caloric values of various components of A. mongolicum, and the caloric values are positively correlated with carbon, nitrogen, and phosphorus contents. Enclosure cultivation significantly reduced carbon, nitrogen, and phosphorus in the roots, as well as nitrogen and phosphorus in the spikes, but significantly increased nitrogen in the spikes by 9.78%. The caloric values of A. mongolicum inside and outside the fence in decreasing order were as follows: spikes > leaves > stems > roots. Comparison of cultivation effects between inside and outside the fence showed that the caloric values of the spikes and roots significantly increased by 0.92% and 1.60%, respectively, whereas those of the leaves significantly decreased by 0.70%. Our results demonstrate that the reproductive allocation of elemental nutrients and caloric values in nonreproductive and reproductive organs are plastic to arid environments. [ABSTRACT FROM AUTHOR]

The likelihood changes of the numbers of occurrences, duration and intensity of hydrological droughts in the Weihe River Basin in China were investigated by using the bias-corrected future climate projections from three selected Global Climate Models (GCMs) with two emission scenarios (RCP 4.5, RCP 8.5), and Soil and Water Assessment Tool (SWAT) hydrological model. Results showed that: 1) The frequency of hydrological droughts, drought durations and intensities would have obvious increasing trends in the future under dry GCM condition. However, an opposite decreasing trend was shown under wet GCM condition; 2) Future precipitation changing direction and magnitudes were dominating factor for the likelihood changes of drought characteristics. Forty GCMs project a future precipitation change from −3.42% to +14.24%, which is the largest source of uncertainties. If the observed trends of precipitation and temperature during the last 50 years continue, then the Weihe River Basin would likely be in the dry condition of GCMs; 3) The impacts of temperature on hydrological droughts cannot be neglected and it has direct (evaporation and runoff generation) and larger magnitude indirect effects (precipitation patterns). The presented results have practical applications for regional drought mitigation planning under future climate changes. [ABSTRACT FROM AUTHOR]

Newcastle disease virus (NDV) is a pathogen that most often infects poultry species. In investigating a 2014 outbreak of encephalitis and death among farmed mink ( Mustela vison ), we found pathological and later experimental evidence that NDV can infect and cause severe encephalitic and pneumonic disease in these animals. Our findings confirm the host range of NDV. [ABSTRACT FROM AUTHOR]

In remote sensing–based forest aboveground biomass (AGB) estimation research, data saturation in Landsat and radar data is well known, but how to reduce this problem for improving AGB estimation has not been fully examined. Different vegetation types have their own species composition and stand structure, thus they have different data saturation values in Landsat or radar data. Optical and radar data also have different characteristics in representing forest stand structures, thus effective use of their features may improve AGB estimation. This research examines the effects of Landsat Thematic Mapper (TM) and ALOS PALSAR L-band data and their integrations in forest AGB estimation of Zhejiang Province, China, and the roles of textural images from both datasets. The linear regression models of AGB were conducted by using (1) Landsat TM alone, (2) ALOS PALSAR data alone, (3) their combination as extra bands, and (4) their data fusion, based on non-stratification and stratification of vegetation types, respectively. The results show that (1) overall, Landsat TM data perform better than PALSAR data, but the latter can produce more accurate estimates for bamboo and shrub, and for forests with AGB values less than 60 Mg/ha; (2) the combination of TM and PALSAR data as extra bands can greatly improve AGB estimation performance, but their fusion using the modified high-pass filter resolution-merging technique cannot; (3) textures are indeed valuable in AGB estimation, especially for forests with complex stand structures such as mixed forests and pine forests with understories of broadleaf species; (4) stratification of vegetation types can improve AGB estimation performance; and (5) the results from the linear regression models are characterized by overestimation and underestimation for the smaller and larger AGB values, respectively, and thus, selecting non-linear models or non-parametric algorithms may be needed in future research. [ABSTRACT FROM AUTHOR]

A herpesvirus was isolated during a diagnostic investigation of severe cases of conjunctivitis in feral pigeons ( Columba livia f. domestica ). Isolates of the virus were recovered from throat swabs of the pigeons followed by inoculation of the swab samples in chicken embryo fibroblasts. Pigeons inoculated with the isolated virus had similar clinical signs to those observed in naturally infected birds. Transmission electron microscopy revealed viral structures with typical herpesvirus morphology. Polymerase chain reaction amplification, using herpesvirus-identifying primers resulted in an amplicon of the expected size for herpesvirus. Sequencing of these amplicons and database comparisons identified the herpesvirus UL30 homologue. Phylogenetic reconstructions suggested that the isolated herpesvirus belongs to the Mardivirus genus of Alphaherpesvirinae . Using the current herpesvirus nomenclature conventions, the authors propose that the herpesvirus be named Columbid herpesvirus-1 Heilongjiang. [ABSTRACT FROM AUTHOR]

Polyporaceae is an important fungal family that has been a source of natural products with a range of pharmaceutical activities in China. In our previous study, two polysaccharides, PCWPW and PCWPS, with significant antioxidant and antidepressant activity were obtained from Poria cocos. In this study, we evaluated their potential molecular mechanisms in the immunomodulation of macrophages. PCWPW and PCWPS were characterized by GC–MS analysis to contain 1,3-linked Glcp. ELISA assays results demonstrated that the secretion of TNF-α was significantly enhanced by PCWPW/PCWPS. RNA-seq data demonstrated that PCWPS treatment modulated the expression of immune-related genes in macrophages, which was further confirmed by RT-qPCR assays. The activation of TNF-α secretion was found to be mannose receptor (MR) dependent and suppressed by MR inhibitor pretreatment. Moreover, the amount of TNF-α cytokine secretion in PCWPW/PCWPS-induced RAW264.7 cells was decreased when pretreated with NF-κB or MAPK signaling pathway inhibitors. Collectively, our results suggested that PCWPW and PCWPS possessed immunomodulatory activity that regulates TNF-α expression through the NF-κB/MAPK signaling pathway by binding to mannose receptors. Therefore, PCWPW and PCWPS isolated from Poria cocos have potential as drug candidates for immune-related disease treatment. [ABSTRACT FROM AUTHOR]

Background: Abdominal obesity has become an important public health issue in China. Socioeconomic disparities are thought to be closely related to the prevalence of abdominal obesity. Exploring socioeconomic disparities in abdominal obesity over the life course in China could inform the design of new interventions to prevent and control abdominal obesity. Methods: The China Health and Nutrition Survey (CHNS) was a prospective household-based study involving seven rounds of surveys between 1993 and 2011. Twenty three thousand, two hundred and forty-three individuals were followed up over an 18-year period. The mixed effects models with random intercepts were used to assess the effects on abdominal obesity. Six key socioeconomic indicators, with age and age-squared added to the models, were used to identify socioeconomic disparities in abdominal obesity over the adult life course. Results: Prevalence of abdominal obesity increased non-linearly with age over the adult life course. Abdominal obesity was more prevalent in younger than older birth cohorts. Positive period effects on the prevalence of abdominal obesity were substantial from 1993 to 2011, and were stronger among males than females. Prevalence of abdominal obesity was higher among ethnic Han Chinese and among the married [coefficient (95% confidence intervals): 0.03(0.003, 0.057) and 0.035(0.022, 0.047), respectively], and was lower among males [coefficient (95% confidence intervals): − 0.065(− 0.075,-0.055)]. A higher-level of urbanization and higher household income increased the probability of abdominal obesity [coefficient (95% confidence intervals): 0.160(0.130, 0.191), 3.47E− 4 (2.23E− 4, 4.70E− 4), respectively], while individuals with more education were less likely to experience abdominal obesity [coefficient (95% confidence intervals): − 0.222 (− 0.289, − 0.155)] across adulthood. Conclusions: In China, abdominal obesity increased substantially in more recent cohorts. And people with lower educational attainment, with higher household income, or living in more urbanized communities may be the disadvantaged population of abdominal obesity over the adult life course. Effective interventions targeting the vulnerable population need to be developed. [ABSTRACT FROM AUTHOR]

Receiver function (RF) analysis is an indispensable method that is widely utilized to image the deep structure of the crust and upper mantle. Although the P -wave receiver function (PRF) has the advantages of a higher signal-to-noise ratio and higher resolution than S -wave receiver function, the information about P -to- S converted (Ps) phases from velocity discontinuities of the crust and upper mantle is usually obstructed by multiples from shallower crustal interfaces. Sometimes it is difficult to identify useful information about lithospheric discontinuities. In this paper, we propose a method for suppressing multiples and isolating the Ps phases of RFs. This task is accomplished by exploiting the differences in arrival times resulting from the slowness between the conversion and the multiples that occur at the same interface in the PRFs and by separating them in the Radon domain, which enables removal of crustal and sedimentary multiples. This method can effectively remove multiples and isolate the useful signals of Ps phases contained in the PRFs. We test the method on synthetic PRFs and demonstrate that crustal multiples can be effectively eliminated or suppressed and that the Ps phase of lithospheric discontinuities can be coherently traced. Next, we apply the method to real PRF data collected from the seismic station of the China Array seismic experiment (Phase II and Phase III) in the Ordos block and its adjacent area, and successfully obtain an improved common conversion point stacking image of lithospheric discontinuity structures in the depth domain, particularly for detecting the lithosphere–asthenosphere boundary. [ABSTRACT FROM AUTHOR]

Abstract Baseflow is the portion of streamflow that originates from groundwater. It is pivotal to groundwater supply as well as the interactions between groundwater and surface water. In the Loess Plateau of China, the baseflow plays a fundamental role in sustaining the aquatic ecosystem. Rational estimation of baseflow is of critical importance for understanding the functioning of the groundwater system and informing management of regional water resources. In this study, a two-well parameterised digital filter was used to separate baseflow from observed daily total streamflow on the Weihe River Basin. Two parameters (maximum baseflow index (BFI max) and the recession constant) of this filter were estimated using UKIH and a recession analysis with physical meaning, respectively. The results show that the baseflow index increased from the upstream to downstream (0.27–0.32) of the Weihe River, and the baseflow of the river is summer dominant. In general, the baseflow has been increasing gradually owing to the implementation of soil conservation measures. This study provides an understanding of baseflow response to seasonal variability and water environmental management in basin scale. Highlights • The baseflow in the loess regional catchment with the spatial attributes. • Baseflow shows a gradually increasing trend from upstream to downstream in the Weihe River Basin. • The baseflow of this river is dominated by summer baseflow. [ABSTRACT FROM AUTHOR]

Available soil water in the root zone is an essential component of the water balance process since it greatly affects the crop water uptake and crop growth. In this study, a modified soil water deficit index (MSWDI) was established on the basis of the concept of readily available water (RAW), with the accumulated effect considered. This modified index was applied in six agro-meteorological stations in Songnen Plain of China to monitor the agricultural drought. The results showed that: 1) The MSWDI showed similar spatial and temporal agricultural drought patterns as its inherent indices, such as the soil water deficit (SWD), soil moisture deficit index (SMDI) and atmospheric water deficit (AWD), but exhibited a delay between atmospheric and soil water processes; 2) The MSWDI has a better correlation with the crop yield than its inherent indices. For example, its overall correlation coefficient is about 0.6 with the crop yields among six study stations and −0.7 for the number of droughts, while their corresponding values are 0.5 and −0.6, 0.5 and −0.6, and 0.3 and −0.4 for SMDI, SWD and AWD, respectively; 3) The MSWDI could also identify a slightly higher number of reported drought events during the 2000–2012 in comparison with SMDI, SWD and AWD, although it also over-predicts the number of drought events same as other indices. It mainly comes from the uncertainty of reported drought events. The proposed index can be used for agricultural drought monitoring and provides a useful tool for agricultural meteorology and water resource management. [ABSTRACT FROM AUTHOR]

The Yinchuan-Hetao (YC-HT) graben is the boundary zone between the Ordos and the Alax blocks in NW China, which shows tectonic patterns distinct from the Haiyuan arcuate and Liupanshan thrust belts to the south. As a Cenozoic rift, the YC-HT graben originated from back-arc spreading related to westward subduction of the western Pacific, but its deformation and development may have been more influenced by the extension of the northeastern Tibetan Plateau (NETP) since the Quaternary. To investigate the dynamics of deep deformation of the YC-HT graben and adjacent regions, we apply the receiver function method to obtain the seismic structure in this area. Our results show that the depth of the Moho beneath the YC-HT graben is ∼50 km and significantly greater than that beneath the Alxa and Ordos blocks. The crust of the Ordos block is characterized by a layered structure, and the intracrustal structure below the YC-HT graben has undergone significant deformation. The Vp/Vs ratio in a local area of the western Hetao graben is as high as ∼1.9. By combining our observations with previous geophysical and geological studies, we speculate that the influence of NETP expansion has reached the YC-HT graben at depth. Meanwhile, the upper and lower crust experienced different deformation modes in this area, which manifested as elastic deformation in the upper crust and plastic deformation in the lower crust. [Display omitted] • Crustal velocity discontinuity structure and Vp/Vs ratios are obtained in the northwestern border of the Ordos, NW China. • Thickened crust and high Vp/Vs anomalies in the crust dominate the Yinchuan-Hetao graben. • Upper and lower crust beneath the Yinchuan-Hetao graben have undergone extensional and thickening deformation respectively. [ABSTRACT FROM AUTHOR]

Crabs are among the most important benthos in intertidal marshes. Numerous studies have shown that they can influence soil properties and soil-surface water exchange through bioturbation. However, little is still known about the effects of crab burrows on sediment microbes. In this study, we examined the effects of crab burrows on the community structure and interaction pattern of soil microbes in sediments in an intertidal marsh of the Yellow River Delta, north China using high-throughput sequencing and co-occurrence network analyses. Results showed that crab bioturbations altered soil microbial community composition both within the fungal and bacterial communities. Network analyses results indicated that the modularity of fungal networks decreased after crab bioturbation. Further, bacterial and fungal functional predictions indicated the relative abundances were significantly lower for fungal saprotrophs and saprotroph-pathotrophs in the soil mound sediment, while significantly higher for bacterial chemoheterotrophs and aerobic chemoheterotrophic in the burrow wall sediment. Our results demonstrate that crab bioturbation can modify the microbial community structure and function, and thus nutrient cycling through degradation of organic matter, a key ecosystem processes in intertidal marsh. • Crab bioturbations altered soil fungal and bacterial communities. • The modularity of soil fungal networks decreased after crab bioturbations. • Crab bioturbations changed abundance of soil bacterial and fungal functional group. [ABSTRACT FROM AUTHOR]