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Strombidae is one of the major molluscan families in Sudan and due to their opercula, has tremendous economic value. In traditional Sudanese homemade perfumes and body care cosmetics, Strombidae family operculum is one of the main ingredients. Their fumigation generates a charming odor preferred by Sudanese people, used for body smoke baths by married women. Moreover, these fumes are believed to treat several gynecological disorders. In this study, we attempted to confirm the presence of volatiles with pleasant odors and compounds with pharmaceutical importance in the Strombidae opercula. Volatiles from the smoke and soak extracts of the burned opercula were analyzed using gas chromatography-mass spectrometry (GC-MS). Furthermore, polar components from the methanol extract of opercula powder were isolated using high-performance liquid chromatography (HPLC) and identified by nuclear magnetic resonance (NMR), electrospray ionization mass spectrometry (ESI-MS), and UV spectra. The elemental and metal contents were analyzed using inductively coupled plasma-mass spectrometry (ICP-MS). GC-MS analysis revealed several phenols, aldehydes, ketones, and other functional fragrant and volatile constituents. Further, two compounds were purified from the methanol extract of Strombidae opercula, and named compounds B and D, which were identified as cyclo-(Tyr-Gly) and 4-hydroxybenzaldehyde, respectively. ICP-MS analysis revealed the presence of various elements and metals at different levels. These findings support the historical and traditional practices and usage of the Strombidae opercula in therapeutic and esthetic products. The opercula contains many biologically active compounds and produces smoke containing volatile scent compounds, which might provide alternative pharmaceuticals and cosmetic ingredients that can cooperate to improve the manufacturing of numerous medical products.

Arbuscular mycorrhizal (AM) fungi often occur in mangrove ecosystems, but how different AM fungi interact with mangrove plants is still unclear. Here, we aimed to study the root colonization patterns of AM fungi in two major mangrove tree species, Rhizophora stylosa Griff. and Bruguiera gymnorhiza (L.) Lam., that dominate the estuarine and freshwater sides of an ecotone. We sampled the roots and soils in a mangrove forest on an island in southern Japan and examined the root colonization rates and community compositions of AM fungi using microscopy and high-throughput sequencing of the small subunit (18S) rRNA gene. Microscopy revealed AM fungal structures in roots from some individuals of B. gymnorhiza but not of R. stylosa. Molecular analysis detected DNA sequences of Glomeraceae species in roots of both species, but detected those of Acaulosporaceae species only in B. gymnorhiza roots. Glomeraceae species were associated with higher soil electrical conductivity (EC), and Acaulosporaceae species with lower soil EC. The presence/absence of sequences of Acaulosporaceae species was significantly associated with the presence/absence of AM fungal structures (microscopic evidence) in B. gymnorhiza. Our results suggest that salinity influences AM fungal community composition in mangrove soils, and that AM fungi such as Acaulosporaceae species form trophic associations with B. gymnorhiza and could help mangrove tree nutrition in saline and low-nutrient environments.

There is little knowledge about microbial functional community structures and the relationships between microbial communities and nitrogen transformation processes. Here, we investigated the relationships between soil microbial communities and nitrogen mineralisation potentials in a cool temperate forest throughout the growing season. Microbial communities were assessed by quantification of the total bacterial, archaeal, and fungal gene abundances and the bacterial and archaeal amoA gene abundances, functional predictions of bacteria and fungi, and analysis of the bacterial-fungal co-occurrence network. In mid-summer, ectomycorrhizal fungal abundance was significantly higher, whereas the total bacterial abundance was significantly lower. Bacterial and archaeal amoA gene abundances were also significantly higher in mid-summer. However, regardless of the seasonal fluctuation of microbial gene abundances, the net nitrification and nitrogen mineralisation potential did not show clear seasonality. In the network analysis, the microbial community was divided into 13 modules, which were subgroups assumed to have similar niches. Furthermore, two modules that mainly consisted of microbial species of Proteobacteria and Bacteroidetes were significantly and positively correlated with the net nitrification and mineralisation potentials. Our results indicated that microbial subgroups sharing similar niches, instead of total microbial abundances and functional gene abundances, could be important factors affecting the net nitrogen mineralisation potential.

We investigated arbuscular mycorrhizal (AM) fungal communities in secondary forests and/or Chamaecyparis obtusa plantations at eight study sites in Japan's temperate region. In the secondary forests, AM plants of the families Lauraceae, Sapindaceae, Rutaceae, Araliaceae, Rosaceae, Magnoliaceae, Cornaceae, Piperaceae, and Anacardiaceae were found. The AM fungal communities were evaluated based on compositions of the AM fungal operational taxonomic units (OTUs), which were clustered at a 97% similarity threshold of the sequences of a partial small subunit of a nuclear ribosomal RNA gene obtained from the plant roots. The compositions of AM fungal OTUs were significantly correlated with the plant family compositions and were significantly differentiated among the study sites and between the study forests. Interestingly, only 19 OTUs remained after selecting for those that had more than 1.0% of the total reads, and these 19 OTUs accounted for 86.3% of the total rarefied reads that were classified into 121 OTUs. Furthermore, three dominant OTUs constituted 48.0% of the total reads, and the most dominant OTU was found at all study sites, except at one. These results indicate that AM fungal communities are primarily constituted by limited AM fungal taxa in the forest ecosystems with diverse plant taxa in Japan's temperate region. The results of basic local algorithm search tool (BLAST) searches against MaarjAM, a database of AM fungal sequences, also revealed that the AM fungi which were the three dominant OTUs are distributed in forest ecosystems on a worldwide scale.

Arbuscular mycorrhizal fungi (AMF) are important components of the grassland ecosystems in terms of plant phosphorus uptake and accumulation of glomalin-related soil protein (GRSP). Though Mongolian grasslands are seriously degraded by livestock grazing, the effects of grazing on soil AMF and GRSP remain unclear. Here, we examined community composition and diversity of AMF as well as amount of GRSP at three different grazing intensities: lightly grazed (LG), moderately grazed (MG), and heavily grazed (HG) under two different types of grassland, mountain forest steppe at Hustai and desert steppe at Mandalgobi. The diversity and biomass of AMF-host and non-AMF plants strongly affected the overall AMF community composition and its diversity. When we separately analyzed the factors affecting soil AMF diversity at Hustai and Mandalgobi, decrease in the shoot biomass of Poaceae plants at Hustai and decreases in the species number and shoot biomass of AMF-host plants at Mandalgobi were significantly correlated with AMF diversity. GRSP decreased with increasing grazing intensity, which was significantly correlated with soil pH and total root biomass at Hustai. The decrease in plant biomass caused by grazing thus led to GRSP reduction. Our results showed that change in soil AMF community caused by livestock grazing were associated with change in the biomass and diversity of functional vegetation groups such as Poaeceae, AMF-host and non-AMF plants, indicating the importance to focus on such functional vegetation groups to evaluate the effect of grazing on AMF.

Mesembryanthemum crystallinum L. (common ice plant) is an edible halophyte. However, if ice plants are used to phytoremediate salinity soil, there are problems of slow initial growth, and a long period before active NaCl uptake occurs under higher salinity conditions. Application of endophytic bacteria may improve the problem, but there remain gaps in our understanding of how endophytic bacteria affect the growth and the biochemical and physiological characteristics of ice plants. The aims of this study were to identify growth-promoting endophytic bacteria from the roots of ice plants and to document the metabolomic response of ice plants after application of selected endophytic bacteria. Two plant growth-promoting endophytic bacteria were selected on the basis of their ability to promote ice plant growth. The two strains putatively identified as Microbacterium spp. and Streptomyces spp. significantly promoted ice plant growth, at 2-times and 2.5-times, respectively, compared with the control and also affected the metabolome of ice plants. The strain of Microbacterium spp. resulted in increased contents of metabolites related to the tricarboxylic acid cycle and photosynthesis. The effects of salt stress were alleviated in ice plants inoculated with the endobacterial strains, compared with uninoculated plants. A deeper understanding of the complex interplay among plant metabolites will be useful for developing microbe-assisted soil phytoremediation strategies, using Mesembryanthemum species.

Fungi are one of the most diverse groups of organisms and considered as one of the least-explored biodiversity resources. Soil fungal community was investigated in two agricultural sites in Khartoum state, Sudan, during two seasons. A total of 42 soil samples were collected, their physicochemical properties were determined, then subjected to metabarcoding and metagenomic analyses. fungal community composition, diversity and microbial trophic modes were determined utilizing R software packages. From both sites, a total of 15 different phyla were detected, out of them, 11 were the most abundant and frequent. Ascomycota was the dominant phylum (86.54% total abundance), followed by the Basidiomycota (8.29%). The dominant class was Sordariomycetes (41.02%), followed by Dothideomycetes (19.80%). Aspergillus (6.2%), Curvularia (6.0%), Neurospora (5.8%) and Fusarium (4.9%) were the most abundant genera. Deniquelata for the first time being recorded in Sudan. Apha diversity measures revealed sample richness ranging from 71 to 361 ASVs, and Shannon index ranging from 2.794 to 5.087. The two sites had significantly different alpha diversity. Land-use types were also significantly different in their diversity regardless of site. Season had no effect on alpha diversity of soil fungal communities. Beta diversity analysis indicated significant differences between the two sites and the different land-use types. No significant differences in the community structure recorded between the two seasons. The dominant trophic mode among the assigned ASVs in soil mycobiome was saprotroph mode (22.11%). Results of this study reveals that fungal community structure is affected by site and land-use type. It gives a comprehensive database for the mycobiome of the agricultural soil in Khartoum state.

Despite the economic importance of sorghum in Sudan, its productivity is low. Arbuscular mycorrhizal fungi (AMF) enhance sorghum growth, survival, and nutrient uptake, and their manipulation may have potential in mitigating biotic and abiotic stresses during droughts. However, information on the AMF community in Sudan and the host-AMF specificity at the sorghum genotype level are unknown. We investigated the AMF community structure of 19 sorghum genotypes by next-generation sequencing in a semi-arid region. A total of 102 AMF operational taxonomic units (OTUs) were detected comprising four families: Glomeraceae (85.3%), Claroideoglomeraceae (10.8%), Paraglomeraceae (2.9%), and Diversisporaceae (1%). Among them, appearance ratio of three OTUs (2.9%) belonging to Rhizoglomus was more than 75%, whereas 75 OTUs had lower appearance ratio than 25%, indicating that the AMF community comprised a small number of generalist and a large number of rare OTUs. Non-metric multidimensional scaling and permutational multivariate analysis of variance showed no AMF specificity of the sorghum genotypes. The community assembly was strongly influenced by neutral processes, but 11 OTUs had higher relative frequency than expected by neutral model. The result includes the possibility that adaptability of AMF to soil environment and positive selection by host plant also affect the AMF community assembly. Our work showed that only a few Rhizoglomus species dominated without host plant genotype specificity in a semi-arid Sudanese cropland. Further research on functional analysis of the dominant AMF species may reveal the importance of the dominant AMF species for sorghum cultivation in Sudan.

Tree species influence the chemical properties of the organic horizon and mineral soil. Microbial communities, including fungi and bacteria, which are the main drivers of nutrient cycles in forest soils, may be affected by tree species via litter chemical properties and root exudation. Therefore, conversion from natural forest to plantation could affect the microbial communities. Here, we aimed to reveal the effects of conversion from natural forest to coniferous plantation on soil microbial community structure, biodiversity, and co-occurrence networks, as well as soil chemical properties. For this purpose, we investigated chemical and microbial properties of the organic horizon and mineral topsoil (0–10 cm depth) in three forest types (a natural forest dominated by broad-leaved deciduous trees, and two types of plantations). Forest type had significant effects on chemical properties, including the C/N ratio, pH, and dissolved inorganic N of the organic horizon, while it had no significant effect on the chemical properties of topsoil, except for microbial biomass N and C. Microbial community structures in both the organic horizon and topsoil differed significantly among forest types and with changes in soil properties such as pH and C/N ratio. Microbial diversity indices did not significantly differ among forest types in either layer, while the microbial co-occurrence networks in the mineral soil of the natural forest were more complex and robust than the networks of plantations. Therefore, our results showed that conversion from natural forest to coniferous plantation could affect soil chemical properties and microbial community structure in the organic horizon, and the microbial co-occurrence network in the mineral topsoil; these impacts may vary according to the planted tree species.

Rainfall patterns are predicted to change dramatically in many terrestrial landscapes, including drylands. The most limiting resources for plant growth in arid regions is nitrogen (N) as well as water. A natural aridity gradient provides appropriate candidate conditions for predicting the impacts of changes in rainfall on soil N dynamics. To comprehensively and mechanistically examine soil N dynamics, we focused on the steps of N transformation, their microbial drivers, and the determining soil properties. We divided the N transformation process into three steps: (i) organic matter degradation, (ii) N mineralization, and (iii) nitrification, which are driven primarily by fungi, prokaryotes, and ammonia oxidizers, respectively. Soil samples were collected from three black locust forests with mean annual precipitations ranging from 449 to 606 mm. Along the aridity gradient, all three steps changed while maintaining a balance. The degradation and mineralization steps varied with changes in the soil fungal and prokaryotic communities, respectively. The compositions of these communities were determined by soil substrate quality and quantity; saprotrophs and copiotrophs decreased along the aridity gradient. On the other hand, the abundance of ammonia-oxidizing bacteria, which correlated with the rate of nitrification, was likely determined by soil moisture. Therefore, if precipitation were to decrease, changes in the nitrification step might be the first mechanism to limit plant productivity in semi-arid forests. This limitation would extend to the other steps in the N cycling process via plant–soil feedback. Thus, N cycling dynamics are predicted to achieve new stable states suited to the changed precipitation regime.

Prevalent salinity hinders the plant growth, and efforts for vegetation are limited due to excessive concentration of salts. The microbiome associated with extreme habitats has the potential of inducing stress avoidance, tolerance, and resistance strategies in the host plants for energy requirements. Manipulation of such interactions offers the potential revegetation, and utilization of saline soils, and with the similar objectives, the rhizosphere of Common ice-plant was explored for incident bacteria helping the plant grow better. The isolation resulted in 152 isolates, and above 50% isolates were observed tolerant to 513 mM of NaCl, and the two, PR-3 and PR-6, most promising even showed tolerance up to 1250 mM salinity. Both the strains showed indole acetic acid production, and 1-aminocyclopropane-1-carboxylate deaminase activity, but neither of them had nitrogen fixation ability. Phosphorus solubilization, and siderophore production was shown by either of them. Plant growth promoting (PGP) assay showed significant root elongation when compared with control, which was further confirmed by the pot experiment where the above-ground part of the Common ice-plant also showed significant growth over control. Concluding, rhizosphere bacteria from the halophyte plant showed different PGP abilities, and thus can be applied for improving the growth of associated plant in saline conditions.

We diagnosed two cases of double aortic arch (DAA) remotely. In both cases, the right aortic arch was suspected, and a remote diagnosis was requested. We performed a remote diagnosis by the spatio-temporal image correlation (STIC) method. DAA was diagnosed by detecting the left aortic arch in an axial transverse section in the three-vessel trachea view. Since the STIC method can make multiple cross sections, making a diagnosis by the STIC method was useful for the remote diagnosis of these patients. In particular, HD flow render mode clearly showed left aortic arch, so it was possible to diagnose DAA.

Loss of beneficial microbes and lack of native inoculum have hindered reforestation efforts in the severely-degraded lands worldwide. This is a particularly pressing problem for Ethiopia owing to centuries-old unsustainable agricultural practices. This study aimed to evaluate the inoculum potential of soils from church forest in the northwest highlands of Ethiopia and its effect on seedling growth of two selected native tree species (Olea europaea and Albizia gummifera) under a glasshouse environment. Seedlings germinated in a seed chamber were transplanted into pots containing sterilized and/or non-sterilized soils collected from under the canopy of three dominant church forest trees: Albizia gummifera (AG), Croton macrostachyus (CM), and Juniperus procera (JP) as well as from adjacent degraded land (DL). A total of 128 pots (2 plant species &times, 4 soil origins &times, 2 soil treatments &times, 8 replicates) were arranged in a factorial design. Overall, seedlings grown in AG, CM, and JP soils showed a higher plant performance and survival rate, as a result of higher soil microbial abundance and diversity, than those grown in DL soils. The results showed significantly higher plant height, root collar diameter, shoot, and total mass for seedlings grown in non-sterilized forest soils than those grown in sterilized soils. Furthermore, the bacterial relative abundance of Acidobacteria, Actinobacteria, and Nitrospirae was significantly higher in the non-sterilized forest soils AG, CM, and JP (r2 = 0.6&ndash, 0.8, p &lt, 0.001). Soil pH had a strong effect on abundance of the bacterial community in the church forest soils. More specifically, this study further demonstrated that the effect of soil microbiome was noticeable on the performance of Olea seedlings grown in the soil from CM. This suggests that the soils from remnant church forests, particularly from the canopy under CM, can serve as a good soil origin, which possibly would promote the native tree seedling growth and survival in degraded lands.

We prospectively performed remote fetal cardiac screening using the spatio-temporal image correlation (STIC), and examined the usefulness and problems of remote screening. We performed heart screening for all pregnant women at four obstetrics clinics over the three years from 2009 to 2014. The STIC data from 15,404 examinations in normal pregnancies (16–27 weeks, median 25 weeks) were analyzed. Obstetricians and sonographer collected STIC data from four-chamber view images. Eight pediatric cardiologists analyzed the images offline. A normal heart was diagnosed in 14,002 cases (90.9%), an abnormal heart was diagnosed in 457 cases (3.0%), and poor images were obtained in 945 cases (6.1%). 138 cases had congenital heart disease (CHD) after birth, and severe CHD necessitating hospitalization occurred in 36 cases. We were not able to detect CHD by screening in 12 cases. The sensitivity and specificity of STIC in CHD screening was 50% and 99.5%, respectively. The sensitivity and specificity of STIC in screening for severe CHD was 82% and 99.9%, respectively. The STIC method was useful in fetal remote screening for CHD. However, the fact that > 10% of images that could not be analyzed by this method was a problem.

Rapid responses of microbial biomass and community composition following a precipitation event have been reported for soil bacteria and fungi, but measurements characterizing ectomycorrhizal fungi remain limited. The response of ectomycorrhizal fungi after a precipitation event is crucial to understanding biogeochemical cycles and plant nutrition. Here, we examined changes in ectomycorrhizal formation, diversity, and community composition at the end of a summer drought and following precipitation events in a conifer–oak mixed forest under a semiarid, Mediterranean-type climate in CA, USA. To study the effects of different amounts of precipitation, a water addition treatment was also undertaken. Ectomycorrhizal fungal diversity and community composition changed within 6 days following precipitation, with increased simultaneous mortality and re-growth. Ectomycorrhizal diversity increased and community composition changed both in the natural rainfall (less than 10 mm) and water addition (50 mm) treatments, but larger decreases in ectomycorrhizal diversity were observed from 9 to 16 days after precipitation in the water addition treatment. The changes were primarily a shift in richness and abundance of Basidiomycota species, indicating higher drought sensitivity of Basidiomycota species compared with Ascomycota species. Our results indicate that ectomycorrhizal formation, diversity, and community composition rapidly respond to both precipitation events and to the amount of precipitation. These changes affect ecosystem functions, such as nutrient cycling, decomposition, and plant nutrient uptake, in semiarid regions. Electronic supplementary material The online version of this article (10.1007/s00572-018-0859-3) contains supplementary material, which is available to authorized users.

The mesic-origin plantation species Robinia pseudoacacia L. has been successfully grown in many arid land plantations around the world but often exhibits dieback and reduced growth due to drought. Therefore, to explore the behavior of this species under changing environmental conditions, we examined the relationship between ecophysiological traits, gas exchange and plant hydraulics over a 3-year period in trees that experienced reduced plant hydraulic conductance (Gp) in summer. We found that the transpiration rate, stomatal conductance (Gs) and minimum leaf water potential (Ψlmin) decreased in early summer in response to a decrease in Gp, and that Gp did not recover until the expansion of new leaves in spring. However, we did not observe any changes in the leaf area index or other ecophysiological traits at the leaf level in response to this reduction in Gp. Furthermore, model simulations based on measured data revealed that the canopy-scale photosynthetic rate (Ac) was 15-25% higher than the simulated Ac when it was assumed that Ψlmin remained constant after spring but almost the same as the simulated Ac when it was assumed that Gp remained high even after spring. These findings indicate that R. pseudoacacia was frequently exposed to a reduced Gp at the study site but offset its effects on Ac by plastically lowering Ψlmin to avoid experiencing any further reduction in Gp or Gs.

Purpose During the implantation period, the uterus goes through many complex, orchestrated changes, including alterations of the glycocalyx that are due to sialylation, sulfation, and fucosylation. A previous mouse study showed that the in vivo intrauterine oxidation‐reduction potential (ORP) aided in determining the alterations in the uterine endometrium that are suitable for implantation and for evaluating prospective uterine receptivity, while the in vivo intrauterine pH did not. It was assessed if the in vivo intrauterine ORP could be a useful parameter to predict pregnancy in women. Methods A prospective cohort study was conducted for patients who had received a frozen‐thawed single embryo transfer in a programmed, hormonally controlled cycle. The in vivo intrauterine ORP was measured 3 times during the treatment cycle, at cycle days 9‐10, 1 day before progesterone administration and immediately before the embryo transfer. Results The amount of in vivo intrauterine ORP at 9‐10 days after the start of menstrual bleeding was significantly lower in the pregnant group than in the non‐pregnant group. A receiver‐operator characteristic curve analysis of the intrauterine ORP as a predictor of non‐conception showed an area under the curve of 0.80. Conclusion The in vivo intrauterine ORP could be a useful parameter to predict pregnancy for the frozen‐thawed embryo transfer treatment cycle.

The impact of increasing numbers of livestock on wild ungulates has been a concern in Mongolia. We used DNA barcoding via next generation sequencing to reveal detailed food habits and assess the extent of potential resource competition among ungulates in the desert steppe of southern Mongolia. From feces of 2 wild (Mongolian gazelle [Procapra gutturosa], Asiatic wild ass [Equus hemionus]) and 4 domestic (sheep [Ovis aries], goat [Capra hircus], horse [Equus caballus], camel [Camelus bactrianus]) ungulates collected in June 2014, we identified 25 plant families (39 to genus and 18 to species). Dietary diversity was the highest for sheep (Levins' standardized index = 0.351), followed by goats (0.342), and the lowest for gazelles (0.220). Gazelles had a high dietary overlap with goats (Pianka's index = 0.654) and sheep (0.630). Wild asses had the highest dietary overlap with horses (0.847), followed by goats (0.727) and sheep (0.719). The high dietary overlaps may be explained by similar digestive systems and body sizes among gazelles, sheep, and goats and between wild asses and horses, and by the high dietary diversity of sheep and goats. The present study shows more diverse food compositions than previous studies, suggesting that because of the high dietary diversity of sheep and goats and their overlap with wild species, their increasing number is a potential risk for the survival of wild ungulates.

Degraded drylands have a limited ecosystem functionality and require well-targeted rehabilitation interventions and sustainable land management for improvement. A promising rehabilitation package using mechanized micro-catchment water harvesting, to support the development of out-planted native shrub seedlings, is being introduced in Jordan's Badia. However, the impacts of rehabilitation on the soil microbial communities through the changes in soil physicochemical properties, and microbial potential contribution to soil function and stability are unclear. In the present study, soil microbial properties (abundance, community structure, community composition, diversity, network complexity, and decomposition function) and their relations with selected physicochemical properties (moisture, pH, salinity, and organic matter quantity and quality) were investigated in the micro-catchment water harvesting bunds in comparison with those in untreated interspace areas four years after implementation. At the bunds, fungal and bacterial abundances increased significantly, as did prokaryotic diversity, prokaryotic function to produce decomposing enzymes, and the redundancy of these functions. Furthermore, Burkholderiales (plant growth-promoting bacteria) and Cytophagales (cellulolytic bacteria) increased in the bunds. Enhanced soil moisture, through the rehabilitation, was likely a key for the improvements of the microbiota, including the increases in the abundances of fungi and the specific bacteria (Burkholderiales and Cytophagales), most of the decomposition function, and the functional redundancy. Furthermore, the decrease in salinity due to leaching resultant from the infiltration of collected surface runoff at the bunds likely supported an increase in diversity and parts of the function. The results suggest that the rehabilitation has multiple beneficial impacts on soil microbial communities, which further contribute to long-term ecosystem functionality and stability.

Native tree species are frequently unable to effectively grow in non-native tree cultivation scenarios. In the Loess Plateau, China, it is difficult to find native oak (Quercus liaotungensis) seedlings in non-native black locust forests. Black locust is an arbuscular mycorrhizal (AM) tree, but oak is an ectomycorrhizal (ECM) tree. Plants highly depend on their symbiotic mycorrhizal fungi to take up water, nitrogen (N) and other nutrients. We hypothesized that black locust forests would not provide ECM inoculum to oak seedlings, limiting their water and nutrient uptake, which would be improved by ECM inoculum. Here, we (1) sowed seeds, with or without oak forest soils, (2) transplanted seedlings collected in oak forests, with or without oak forest soils, and (3) planted seedlings germinated in autoclaved or unautoclaved oak forest soils. We measured the survival and growth rate for all three experiments, along with chemical properties, and root ECM colonization. Oak seeds sowed with oak forest soils had higher mycorrhizal colonization, leaf N concentrations and survival rate, and lower root δ13C than the seeds sowed without oak forest soils. Planting with oak forest soils also increased the survival rate of the germinated seedlings, but not the transplanted seedlings. Overall, our study suggested that the use of oak forest soils in the black locust forest to improve the water and N uptake of oak seedlings by providing the ECM inoculum, resulting in a high survival rate. Our study also implies that the method of sowing seeds was effortless and effectively compared to transplanting wild/nursery seedlings.

Aeolian desertification is the dominant form of land degradation in drylands. The straw checkerboard barrier (SCB) method is effective for sand fixation and has been used to combat aeolian desertification in China. Soil inoculation with ectomycorrhizal (ECM) fungi can help restore degraded lands by improving the soil microbial community and steering plant community development. Combining SCB with afforestation via planting ECM trees and inoculating soil with ECM fungi holds promise for improving plant establishment and growth on shifting sand dunes, but this has yet to be examined. Here, we tested the effects of soil inoculation on ECM colonization of Pinus tabulaeformis roots and the survival and establishment of nursery grown P. tabulaeformis seedlings using three soil treatments: no soil (NS), soil sterilized with fungicide (FPS), and ECM-containing non-treated plantation soil (NPS) collected from a nearby P. tabulaeformis plantation. After two years, P. tabulaeformis survival did not differ among the three soil treatments, but ECM colonization rate, total plant dry weight, and leaf total nitrogen per one seedling in the NPS treatment were 9.0, 2.6, and 3.4 times higher than those in the NS treatment. Water use represented by leaf δ13C was also highest in the NPS treatment. Structural equation modeling showed that soil inoculation enhanced ECM colonization of P. tabulaeformis, thus improving nitrogen uptake and water use, leading to increased plant growth. Suillus, Peziza, Geopora, Tuber, and Tomentella were the dominant genera in NPS treatment; 94% of the ECM roots in the NPS treatment were colonized by ECM fungi not detected in NS treatment, indicating that ECM fungi from the inoculum soil were able to colonize the roots of nursery grown seedlings. Only a few ECM fungal species could colonize P. tabulaeformis roots from the plantation soil inoculated, but the taxonomic diversity including Basidiomycota and functional diversity of mycelial exploration types were increased by soil inoculation. These results suggest that soil inoculation with ECM fungi aids in afforestation with ECM plants for the restoration of degraded drylands, including shifting sand dunes.

The objective of this study was to investigate how plants maintain productivity under a limited supply of water and N along the topographical soil water and N gradients in semi-arid forests. We investigated forest structure and productivity, N cycling, and water and N use by plants at three different slope positions in a forested area near an arid boundary on a loess plateau in China. Net primary production (NPP) and aboveground N uptake decreased as soil water and/or N availability decreased on upper slopes; however, NPP and aboveground N uptake were only slightly lower than those of more humid forest ecosystems. Water use efficiency (WUE), N use efficiency (NUE), and fine root biomass increased as soil water and/or N supply decreased with altitude. High NUE was linked to higher N mean residence time, caused by higher N resorption efficiency rather than increasing N productivity. Our results suggest that NPP and N uptake can be maintained by increasing WUE and NUE and increasing fine root biomass in water and N co-limited semi-arid forest ecosystems near arid boundaries. Such changes in resource use and acquisition strategy can affect production and N cycling via plant-soil feedback systems.

We evaluated phytoremediation potential of a calcareous saline-sodic soil with Prosopis glandulosa relying on either N2 fixation (NFIX) or inorganic N (IN) and gypsum. Straw and root dry matter of NFIX were 60% and 67% higher than that of IN, respectively. While both plants relying on IN or NFIX retained nearly similar Ca2+, Na+ level in IN lysimeters was 1.8 folds that of NFIX, whereas levels of Na+ and K+ in roots of NFIX were 13% and 24% higher than that of IN plants. P. glandulosa relying on NFIX and IN released 39% and 50% Na+ of that released by the gypsum. P. glandulosa produced more than the gypsum treatment and induced 24% of Ca2+ solubilization found in the gypsum treatment. Translocation factor of Na+ and the K+/Na+ ratio in NFIX and IN were 0.58, 0.99 and 13.2, 7.0, respectively. The practical implication of this study conclude that P. glandulosa grown with NFIX or IN is an alternative practice for amelioration of calcareous salt-affected soils.

Microbial transformation of homocholine plays a central role in many biological systems and influence on all kingdoms of life. Here, we used suppression subtractive hybridization (SSH) approach to screen for genes that differentially expressed in response to homocholine by Pseudomonas sp. strain A9 and to gain deep acknowledge about the gene expression and sequences of homocholine degrading enzymes. Twenty-seven differentially expressed genes were identified and were found to involve in the uptake and metabolism of homocholine as well as physiological responses of strain A9 to this compound. Of them, fragments of homocholine dehydrogenase (hcdH), β-alanine betaine aldehyde dehydrogenase (bABALDH), β-alaninebetaine CoA transferase (hcdD), 3-hydroxypropionate dehydrogenase (hcdB), and malonate semialdehyde dehydrogenase (hcdC) genes were detected. After excessive experiments of PCR and sequencing, the full-length sequences of these key genes were identified. Interestingly, a complete sequence of a unique gene cluster (6.2 kbp) of hcd (homocholine degrading) genes that contain the genes hcdD, hcdB, hcdC, and hcdR was obtained. The sequence information of these essential genes will enhance our understanding of homocholine catabolic pathway in microorganisms and will help in identifying better inhibitors or activators of these enzymes to either improve or suppress their activity depending on the importance of the formed metabolite.

Let \begin{document}$ D\subset R^{d}$\end{document} be a bounded domain in the \begin{document}$d- $\end{document} dimensional Euclidian space \begin{document}$R^{d} $\end{document} with smooth boundary $Γ=\partial D.$ In this paper we consider exponential boundary stabilization for weak solutions to the wave equation with nonlinear boundary condition: \begin{document}$\left\{ \begin{gathered}u_{tt}(t)-ρ(t)Δ u(t)+b(x)u_{t}(t)=f(u(t)), \\ u(t)=0\ \ \text{on }Γ_{0}×(0,T), \\ \dfrac{\partial u(t)}{\partialν}+γ(u_{t}(t))=0\ \ \text{on }Γ _{1}×(0,T), \\ u(0)=u_{0},u_{t}(0)=u_{1},\end{gathered} \right.$ \end{document} where \begin{document}$\left\| {{u_0}} \right\| \begin{document}$ E(0) where \begin{document}$λ_{β}, $\end{document} \begin{document}$d_{β} $\end{document} are defined in (21), (22) and \begin{document}$Γ=Γ_{0}\cupΓ_{1} $\end{document} and \begin{document}$\bar{Γ}_{0}\cap\bar{Γ}_{1}=φ. $\end{document}