The impact of sea embankment reclamation on soil organic carbon and nitrogen pools in invasive Spartina alterniflora and native Suaeda salsa salt marshes in eastern China

The construction of sea embankments is an increasingly common approach for controlling the spread of the exotic C-4 perennial grass Spartina alterniflora Loisel. in coastal wetlands of eastern China. However, the impact of sea embankment reclamation on the soil organic carbon (C) and nitrogen (N) dynamics in salt marshes is not fully understood. In this study, we examined the stocks of the total, labile and recalcitrant organic C and N, the recalcitrant indices of C and N, and the concentrations of water-soluble organic carbon (WSOC), microbial biomass carbon (MBC) and cumulative CO2-C mineralization (MINC) in sea embankment-reclaimed S. alterniflora and Suaeda salsa (Linn.) Pall. salt marshes through comparisons with adjacent unreclaimed S. alterniflora and S. salsa salt marshes in a coastal wetland of eastern China. Sea embankment reclamation significantly decreased plant biomass by 55.34%, soil salinity by 81.71%, soil moisture by 43.16%, soil total organic C by 50.60% and total organic N by 49.99%, and also lowered labile and recalcitrant organic C and N, WSOC, MBC and MINC in the invasive S. alterniflora salt marsh. However, sea embankment reclamation did not significantly affect the stocks of the soil organic total C and N, recalcitrant organic C and N, and soil organic C dynamics in the native S. salsa salt marsh, possibly because the total quantity of S. salsa materials entering the soil, soil salinity, moisture and bulk density were not affected by sea embankment reclamation. Our results suggest that the impact of sea embankment reclamation on soil organic C and N pools is much more profound in S. alterniflora salt marsh than in S. salsa salt marsh. Sea embankment reclamation could greatly weaken the C and N sinks of S. alterniflora salt marsh and potentially affect C and N sinks in the coastal wetlands of eastern China. (C) 2016 Elsevier B.V. All rights reserved

Au Nanoparticles-Decorated BiOI Nanosheet Arrays for Cathodic Photoelectrochemical Dopamine Sensors

Photocathode-based photoelectrochemical (PEC) sensors can well evade the intrinsic hole oxidation reactions occurring at the photoelectrode–electrolyte interface and expand the application of PEC sensors in the field of bioanalysis. Herein, a cathodic PEC sensor based on p-type semiconductor bismuth oxyiodide nanosheet arrays (BiOI NSAs) integrated with gold nanoparticles (AuNPs) on indium-doped tin oxide (ITO) electrode (ITO/BiOI NSAs/AuNPs) is fabricated by a two-step electrodeposition method. The local surface plasmon resonance (LSPR) effect of AuNPs facilitates the capability of visible light absorption of the BiOI NSAs. Meanwhile, AuNPs, as an electron reservoir, improve the charge separation efficiency of carriers by forming a Schottky barrier, allowing more electrons to be transferred to O2 dissolved in the electrolyte, consequently promoting the PEC activity of the photoactive materials. Furthermore, dopamine (DA) can enhance the photocurrent of the ITO/BiOI NSAs/AuNPs photoelectrode by binding to Bi3+ on the BiOI NSAs surface to in-situ-form a charge-transfer complex (CTC). Based on this phenomenon, a PEC sensor was designed for the determination of DA, and the PEC sensor showed acceptable results for DA detection in real samples. The PEC sensor demonstrates the prospect of BiOI-based materials in cathodic PEC biosensing

Transcriptome Sequencing and Comparison of Venom Glands Revealed Intraspecific Differentiation and Expression Characteristics of Toxin and Defensin Genes in <i>Mesobuthus martensii</i> Populations

Mesobuthus martensii, a famous and important Traditional Chinese Medicine has a long medical history and unique functions. It is the first scorpion species whose whole genome was sequenced worldwide. In addition, it is the most widespread and infamous poisonous animal in northern China with complex habitats. It possesses several kinds of toxins that can regulate different ion channels and serve as crucial natural drug resources. Extensive and in-depth studies have been performed on the structures and functions of toxins of M. martensii. In this research, we compared the morphology of M. martensii populations from different localities and calculated the COI genetic distance to determine intraspecific variations. Transcriptome sequencing by RNA-sequencing of the venom glands of M. martensii from ten localities and M. eupeus from one locality was analyzed. The results revealed intraspecific variation in the expression of sodium channel toxin genes, potassium channel toxin genes, calcium channel toxin genes, chloride channel toxin genes, and defensin genes that could be related to the habitats in which these populations are distributed, except the genetic relationships. However, it is not the same in different toxin families. M. martensii and M. eupeus exhibit sexual dimorphism under the expression of toxin genes, which also vary in different toxin families. The following order was recorded in the difference of expression of sodium channel toxin genes: interspecific difference; differences among different populations of the same species; differences between sexes in the same population, whereas the order in the difference of expression of potassium channel toxin genes was interspecific difference; differences between both sexes of same populations; differences among the same sex in different populations of the same species. In addition, there existed fewer expressed genes of calcium channel toxins, chloride channel toxins, and defensins (no more than four members in each family), and their expression differences were not distinct. Interestingly, the expression of two calcium channel toxin genes showed a preference for males and certain populations. We found a difference in the expression of sodium channel toxin genes, potassium channel toxin genes, and chloride channel toxin genes between M. martensii and M. eupeus. In most cases, the expression of one member of the toxin gene clusters distributed in series on the genome were close in different populations and genders, and the members of most clusters expressed in same population and gender tended to be the different. Twenty-one toxin genes were found with the MS/MS identification evidence of M. martensii venom. Since scorpions were not subjected to electrical stimulation or other special treatments before conducting the transcriptome extraction experiment, the results suggested the presence of intraspecific variation and sexual dimorphism of toxin components which revealed the expression characteristics of toxin and defensin genes in M. martensii. We believe this study will promote further in-depth research and use of scorpions and their toxin resources, which in turn will be helpful in standardizing the identification and medical applications of Quanxie in traditional Chinese medicine

The fluid mud flow deposits represent mud caps of Holocene hybrid event beds from the widest and gentlest shelf

The internal fabric of mud caps, which are on top of sediment gravity flow deposits, remains unexplored so far. We identified four hybrid event beds on one of the widest and gentlest shelf (East China Sea Shelf). Three types of lithofacies, including massive sand, chaotic mud and homogeneous mud, were distinguished. Homogeneous mud represents mud caps of these hybrid event beds. Scanning electron microscopy performed in both homogeneous mud and chaotic mud has revealed the presence of mud aggregates (mud clasts) conforming sand-size clasts. Chemical analyses of the aggregates show the presence of abundant gypsum/anhydrite and clay mineral components as well as relicts of quartz, muscovite and feldspar, suggesting an origin related to erosional events and an intraclast origin. The vertical shortening, deformation together with the pore spaces of mud clasts indicate a shallow burial depth of erosion, where mud sediments were still unconsolidated and water-saturated. No background sedimentation is present in the mud caps, because we did not observe any bioturbated interval in core images and X-radiographs. The lack of laminated muds and synsedimentary trace fossils in the homogeneous muds suggest an origin related to fluid mud flows. As proved on previous experiments, the mud caps could be related to head erosion and shearing of the muddy debris flow/mud flow´s upper surface which generated a slower moving fluid mud flow. Our study further confirms that no laminated sand/silt (H4 division) would be present in hybrid event beds with mud-dominated H3 division. Head erosion of muddy debris flow/mud flow would not allow laminated H4 division to form, because the fluid mud flow derived from the parent mud-dominated debris flow was mainly composed of grains smaller than 30 μm which can effectively damp turbulence effectively. Grain size analysis performed on samples from fluid mud flow deposit fall into pelagites/hemipelagites area (T area), suggesting that fluid mud flow deposits are also a candidate for T area, and the area does not necessarily reflect a deposition under un-stressed environment.Fil: Shan, Xin. Ministry of Natural Resources; China. Qingdao National Laboratory for Marine Science and Technology; ChinaFil: Shi, Xuefa. Ministry of Natural Resources; China. Qingdao National Laboratory for Marine Science and Technology; ChinaFil: Qiao, Shuqing. Ministry of Natural Resources; China. Qingdao National Laboratory for Marine Science and Technology; ChinaFil: Jin, Lina. Nanjing University; ChinaFil: Otharán, Germán Aníbal. Universidad Nacional del Sur; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Zavala, Carlos. Universidad Nacional del Sur. Departamento de Geología; ArgentinaFil: Liu, Jianxing. Ministry of Natural Resources; China. Qingdao National Laboratory for Marine Science and Technology; ChinaFil: Zhang, Yingqiu. Qingdao National Laboratory for Marine Science and Technology; China. Ministry of Natural Resources; ChinaFil: Zhang, Dan. East China Normal University; ChinaFil: Xu, Taoyu. Ministry of Natural Resources; China. Qingdao National Laboratory for Marine Science and Technology; ChinaFil: Fu, Chao. China University of Geosciences; Chin

Mating strategies in Chinese culture : female risk avoiding vs. male risk taking

Previous evolutionary literature demonstrating risk taking as a male mating strategy ignored cultural influences and the function of risk avoiding for women. The present research is the first to support the hypothesis that risk taking and risk avoiding, respectively, reflect Chinese male and female mating strategies. In Study 1, when under the impression of being watched by the opposite sex, Chinese men took more risks and women took fewer risks than when watched by a same sex or alone. In Study 2, Chinese male risk taking and female risk avoiding were positively related to their mating-related evaluation of the opposite-sex observer, and these results were reinforced by behavioral findings in Study 3. The implications of the findings regarding Chinese traditional mate preference and the evolutionary mechanism behind it are discussed

Sea-level changes control coastal organic carbon burial in the southern East China Sea during the late MIS 3

Coastal depositional systems play a crucial role in the sequestration of terrigenous organic carbon (OC), especially deltas and coastal mud belts, which are two of the most efficient OC burial hotspots. Investigation into long-term coastal OC burial is challenging since the analysis of modern coastal environments only provides a snapshot of OC burial. Marine Isotope Stage 3 (MIS 3) refers to a unique interval in the last glacial period, characterized by a protracted falling sea level punctuated by millennial-scale climate oscillations. The study of OC burial during MIS 3 can help to estimate and predict changes in coastal OC burial driven by sea-level oscillations and extreme climate events. Here, we target late MIS 3 strata beneath the southern East China Sea. Based on the analysis of total organic carbon, total nitrogen content, stable organic carbon isotopic composition, and major and trace elements, this study demonstrates that relative sea-level changes control sediment provenance and sedimentary processes in coastal environments, which in turn regulate coastal OC burial during the late MIS 3. The burial of OC in the coastal ocean during MIS 3 deviates from the typical expectation that carbon burial is facilitated during transgression or high sea-level periods. Sediments deposited during high sea-level periods in late MIS 3 exhibit the lowest OC burial flux and contents due to long-distance transport from distant sources. The study highlights that the highest burial flux and contents of OC were found in deposits preserved during sea-level lowstands. This indicates that short-distance transport, local sources, and mountainous rivers affected by the monsoon and experience frequent floods, are associated with the highest OC burial and contents. Short and rapid climate warming events likely contribute to OC burial in late MIS 3 by intensifying precipitation and nutrient-rich supplies, thereby increasing the input of terrestrial and marine OC. This observation is noteworthy as it challenges the conventional understanding of the relationship between sea level and carbon burial. The study of OC burial in late MIS 3 is helpful in understanding how OC burial reacts to sea level oscillations and rapid climate warming events