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Arbuscular mycorrhizal fungi (AMF) form a near-ubiquitous mutualistic association with roots to help plants withstand harsh environments, and play a key role in the establishment of coastal beach plant communities. Yet little is known about the structure and composition of AMF communities on coastal beaches of eastern China. In this study, we investigated the occurrence, community composition and diversity of AMF associated with common wild plants on a coastal beach of North Jiangsu, China. Almost all of the local wild species were colonized by AMF except for Chenopodium album L. Thirty-seven AMF species were isolated from the rhizosphere belonging to 12 genera in seven families. Glomus was the dominant genus and Funneliformis mosseae the dominant species. The colonization, spore composition and diversity of AMF were strongly related to edaphic factors. Sodium (Na+) ions in the soil significantly and negatively affected the colonization rate by AMF and both soil Na+ levels and pH had a significant negative effect on AMF spore density and evenness. However, there was a significant positive correlation between species richness and total organic carbon. The results provide insights into soil factors affecting native AMF communities in coastal beach habitats which could benefit vegetation recovery and soil reclamation efforts.

The stability of soil aggregates is critical for maintaining soil structures and is positively correlated with soil resident organic and inorganic colloids. Forest conversion and soil depth affects the formation of soil aggregates; however, the detailed mechanisms involved in their stabilization have not been well investigated. Therefore, to explore the main factors that influence the stability of soil aggregates for different forest types and soil depths, twelve soil samples were collected from four types of forests (native, mixed, Chinese fir, and bamboo forest) and three soil depths (0–10 cm, 10–20 cm, and 20–30 cm) in subtropical forests. The results revealed that the distributions and mean weight diameters (MWDs) of large macroaggregates in the bamboo forest were significantly lower than those in the other forest types at all soil depths (p < 0.05). Organic and inorganic colloids (organically-complexed Fe oxide and fulvic acid) in the soil directly impacted the stability of soil aggregates, while soil properties (e.g., pH and bulk density) indirectly promoted soil aggregate stability through the modification of colloids. In both native and bamboo forests, organic colloids contributed most to the stability of soil aggregates, reaching 80.31% and 61.37%, respectively. The contributions of organic colloids were found to decrease with soil depth, which was primarily due to changes in the organic matter caused by the decomposition of litter. Elucidating and promoting the specific contributions of organic and inorganic colloids on the stability of soil aggregates will be increasingly important for the optimal management of different forest types.

Background. Diagnosed as a kind of vascular neoplasm of infancy, hemangioma (HA) occurs mainly due to the aberrant proliferation of endothelial cells. Existing evidence has manifested the close relationship of long noncoding RNAs (lncRNAs) with the pathogenesis of HA. Although lncRNA DSCAM antisense RNA 1 (DSCAM-AS1) has been revealed to be implicated in the progression of human diseases, the underlying mechanism DSCAM-AS1 exerts in HA formation is unclear. Aims. To figure out how DSCAM-AS1 may regulate the progression of human hemangioma endothelial cells (HemECs). Methods. DSCAM-AS1 expression was verified through RT-qPCR detection. Functional assays including EdU assay, colony formation assay, flow cytometry analysis, TUNEL assay, and transwell assay were applied to evaluate cell proliferation, apoptosis, and migration upon DSCAM-AS1 knockdown. Moreover, RNA pull-down assay, luciferase reporter assay, RIP assay, and other mechanism experiments were utilized for evaluating the correlation of DSCAM-AS1 and RNAs in HemECs. Results. DSCAM-AS1 knockdown inhibited proliferative capability and migratory capability of HemECs whereas expedited apoptosis. Molecular mechanism results testified DSCAM-AS1 could function as a ceRNA to bind miR-411-5p in HemECs. Besides, it was confirmed that tumor protein D52 (TPD52) served as a downstream target of miR-411-5p in HemECs. More importantly, related rescue assays uncovered that elevated expression of TPD52 or inhibited expression of miR-411-5p reversed the repressive progression of HemECs mediated by DSCAM-AS1 depletion. Conclusion. DSCAM-AS1 expedited HA progression via miR-411-5p/TPD52 pathway, which provided a novel therapeutic option for HA treatment.

Microbial weathering processes can significantly promote soil properties and enhance rock to soil ratio. Some soil-inhabiting bacteria exhibit efficient rock-dissolution abilities by releasing organic acids and other chemical elements from the silicate rocks. However, our understanding of the molecular mechanisms involved during bacterial rock-dissolution is still limited. In this study, we performed silicate rock-dissolution experiments on a novel Pseudomonas sp. NLX-4 strain isolated from an over-exploited mining site. The results revealed that Pseudomonas sp. NLX-4 strain efficiently accelerates the dissolution of silicate rocks by secreting amino acids, exopolysaccharides, and organic acids. Through employing genome and transcriptome sequencing (RNA-seq), we identified the major regulatory genes. Specifically, fifteen differentially expressed genes (DEGs) encoding for siderophore transport, EPS and amino acids synthesis, organic acids metabolism, and bacterial resistance to adverse environmental conditions were highly up-regulated in silicate rock cultures of NLX-4 strain. Our study proposes a novel bacterial based approach for improving the ecological restoration of over-exploited rock mining-sites.

In this study, an innovative method was used to assess the spatial and temporal patterns of the hydrological connectivity in soil profiles in the Yellow River Delta wetland. In this method, field dye-tracing experiments conducted in the study area (i.e., large [LWa] and small communities [LWb] of Phragmites australis and Suaeda glauca [JP]) were considered, and the root-soil interface in the region and the status of the wetland degradation were analyzed. The results revealed that the index of hydrological connectivity (IHC) significantly changed both spatially and temporally. The high IHC values reaching a 0.392 ± 0.209 gradient were concentrated in the middle and western parts of the study areas. The spatial distribution of the high hydrological connectivity has been extremely fragmented since 2010. The LWb (severely degraded wetland) and JP (extremely degraded wetland) were found to be more seriously degraded than the LWa (moderately degraded wetland) in the study area. The changes in the IHC were positively correlated with the principal component (PC) values of the wetland degradation. The IHC is a novel indicator of the status of wetland degradation. Furthermore, the soil holding capacity, soil non-capacity porosity, and soil ventilation were relatively important for the changes in the IHC. Compared with the soil properties, the hydrological responses of the roots systems can be neglected at the root-soil interface. Based on our results, we propose an alternative wetland restoration solution for the Yellow River Delta wetland: 1) a seepage layer in the surface soils (0–10 cm), shallow ploughing treatment, and litter or straw return to the soil surface should be conducted to increase the hydrological connectivity of the soil surface; 2) reeds should not be reaped every year to remove the nutrients from this area; and 3) appropriate freshwater inputs should be strengthened.

Because diabetic foot ulcers (DFUs) are difficult to heal and cause huge economic losses to the society, accelerating their healing has become extremely important. The purpose of this study was to evaluate the effect of revascularization based on the angiosome concept on DFU.Between January 2018 and July 2020, 112 consecutive legs with DFUs, in 111 patients who were discharged from the vascular surgery department of our hospital were retrospectively evaluated. The legs were assigned to two groups depending on whether direct arterial flow to the foot ulcer based on the angiosome concept was achieved. Comparisons of the ulcer healing rate, mean time to ulcer healing, major amputation rate, survival rate, and major amputation-free survival rate between the angiosome direct revascularization (DR) and angiosome indirect revascularization (IR) groups were performed.DR was achieved in 71 legs (63%) compared with IR in 41 legs. The ulcer healing rate (70.4% in the DR group versus 34.1% in the IR group, P 0.01), the mean time to ulcer healing (7.01 ± 4.26 months versus 10.09 ± 3.24 months, P 0.01), the survival rate (90.1 vs. 53.7%, P 0.01), and the major amputation-free survival rate (81.7 vs. 48.8%, P 0.01) were significantly higher in the DR group than in the IR group. Undergoing DR did not significantly reduce the major amputations rate compared to IR (13.4 and 34.1%, respectively, P = 0.15), but there might be a trend. In multivariate models, DR remained a significant predictor for ulcer healing (HR, 7.07; 95% confidence interval (CI), 6.54-7.60, P 0.01). Opening multiple infrapopliteal arteries in the DR group compared with restoring only one infrapopliteal artery did not significantly improve the ulcer healing rate (P = 0.59), the mean time to ulcer healing (P = 0.70), major amputation rate (P = 0.83), the survival rate (P = 0.31), and the major amputation-free survival rate (P = 0.40).Attaining a direct arterial flow based on the angiosome concept may be important for ulcer healing, survival, and amputation-free survival in diabetic foot patients. Opening multiple infrapopliteal arteries in DR patients may not improve the ulcer healing, survival, major amputation or amputation-free survival compared with single DR vessel patency.

Background China has been increasingly subject to significant acid rain, which has negative impacts on forest ecosystems. Recently, the concentrations of NO3− in acid rain have increased in conjunction with the rapid rise of nitrogen deposition, which makes it difficult to precisely quantify the impacts of acid rain on forest ecosystems. Methods For this study, mesocosm experiments employed a random block design, comprised of ten treatments involving 120 discrete plots (0.6 m × 2.0 m). The decomposition of fine roots and dynamics of nutrient loss were evaluated under the stress of three acid rain analogues (e.g., sulfuric (SO42−/NO3− 5:1), nitric (1:5), and mixed (1:1)). Furthermore, the influences of soil properties (e.g., soil pH, soil total carbon, nitrogen, C/N ratio, available phosphorus, available potassium, and enzyme activity) on the decomposition of fine roots were analyzed. Results The soil pH and decomposition rate of fine root litter decreased when exposed to simulated acid rain with lower pH levels and higher NO3− concentrations. The activities of soil enzymes were significantly reduced when subjected to acid rain with higher acidity. The activities of soil urease were more sensitive to the effects of the SO42−/NO3− (S/N) ratio of acid rain than other soil enzyme activities over four decomposition time periods. Furthermore, the acid rain pH significantly influenced the total carbon (TC) of fine roots during decomposition. However, the S/N ratio of acid rain had significant impacts on the total nitrogen (TN). In addition, the pH and S/N ratio of the acid rain had greater impacts on the metal elements (K, Ca, and Al) of fine roots than did TC, TN, and total phosphorus. Structural equation modeling results revealed that the acid rain pH had a stronger indirect impact (0.757) on the decomposition rate of fine roots (via altered soil pH and enzyme activities) than direct effects. However, the indirect effects of the acid rain S/N ratio (0.265) on the fine root decomposition rate through changes in soil urease activities and the content of litter elements were lower than the pH of acid rain. Conclusions Our results suggested that the acid rain S/N ratio exacerbates the inhibitory effects of acid rain pH on the decomposition of fine root litter.

The biological pretreatment for the enzymatic hydrolysis of lignocellulosic biomasses largely depends on an effective pretreatment process. A significant enhancement of enzymatic saccharification was obtained with corn stover using Bacillus sp. P3. The hemicellulose removal from corn stover by the strain Bacillus sp. P3 was evaluated for enhancing subsequent enzymatic hydrolysis. Therefore, our study revealed that an alkaline resistant xylanase produced by Bacillus sp. P3 in fermentation broth led to a substantially enhanced hemicellulose removal rate from corn stover within pH 9.36–9.68. However, after 20 d pretreatment of corn stover by the strain P3, the glucan content was increased by 51% and the xylan content was decreased by 35%. After 72 h of saccharification using 20 U g− 1 of commercial cellulase, the yield of reducing sugar released from 20 d pretreated corn stover was increased by 56% in comparison to the untreated corn stover. Therefore, the use of the strain P3 could be a promising approach to pretreat corn stover for enhancing the enzymatic hydrolysis process of industrial bioenergy productions.

Mangrove and salt marsh ecosystems are one of the most productive ecosystems in terrestrial ecosystems, playing an important role in global carbon (C) cycling. The anaerobic condition in coastal wetland usually impedes the decomposition of soil organic carbon (SOC). However, the intrinsic stabilization mechanisms of SOC other than environmental factors are poorly understood in coastal wetland. In this paper, we investigated the relative contribution of mineral association and chemical compounds in maintaining the stabilization of SOC in the mangrove/salt marsh ecotone, and how the microbial community is involved in the stabilization. From NMR spectroscopy, we found that the SOC molecular structure of Spartina. alterniflora soils is simpler than that in mangrove forest, indicating an increased SOC decomposition with invasion of S. alterniflora. On the contrary, the molecular structure of SOC in mangrove forest was dominated by recalcitrant aromatic C. Meanwhile, the larger fractions of silt/clay content in S. alterniflora and the transitional community were corresponding to higher percentage of mineral organic carbon (MOC), which suggest that the SOC in S. alterniflora vegetated soil was mainly protected by the mineral association. The transitional community contained highest MOC content probably due to both physical protection of mineral association and recalcitrant C input from adjacent mangroves. We also found that the fraction of SOC and its chemical structure of functional groups were associated with microbial communities. This study revealed the occurrence of different SOC stabilization mechanisms between mangroves and salt marshes. The knowledge gained may help to make predictions about future SOC dynamics as the different stabilization processes may response to climate change or human activities differently.

Forest conversion may affect the soil microbial community through impacts on soil properties. However, our understanding of the effects on the soil bacterial community remains limited. The objective of this study was to understand the impacts of forest conversion of native broad-leaved species on soil bacterial structure and diversity. The phylogeny structure and diversity of the soil bacterial communities were compared among four forest types. We found that the soil total nitrogen (TN) and C:N ratios were significantly different between a mixed forest and other forest types. The native forest and mixed forest contained a higher relative abundance of Actinobacteria, Gammaproteobacteria, and Acidimicrobiia compared with the Chinese fir and Bamboo forests, but more unique operational taxonomic units (OTUs) were found in the Chinese fir and Bamboo forests. Soil bacteria in bamboo forest and Chinese fir forest showing a higher diversity but a lower total sequencing number than native forest and mixed forest. Among the soil properties, pH was an important variable that contributing to both soil bacterial communities and soil alpha diversities. Our work suggests that after a long-tern forest conversion, both land-use history and vegetation species strongly influence soil bacteria communities, and soil pH is a main factor that influences soil bacterial structure.

Dendrobium is an important medicinal material in China. It has the effect of nourishing the stomach, nourishing yin and clearing heat. In China, there are many types of Dendrobium, and different Dendrobium species have different efficacy. The present study is aimed at distinguishing three major Dendrobium species from morphological and microscopic identification in Ta-pieh mountains area. In this article, the roots, stems and leaves of Dendrobium huoshanense, Dendrobium officinale, and Dendrobium moniliforme are used as materials to compare the differences of tissues of these three Dendrobium species by morphological indexes and microscopic identification of different Dendrobium. The stem morphology of these three Dendrobium species was significantly different except for stem internodes number and the middle part of the stem diameter by measuring the stems of Dendrobium. To ensure the safe use of Dendrobium, we built a fast and convenient method combining normal and fluorescence microscopy was applied in the present study to distinguish D. huoshanense, D. officinale, and D. moniliforme. The microscopic results show that different types of Dendrobium exhibit different states that can be distinguished under normal light normal and fluorescence microscopy. This comparative study of morphology and microscopy contributes to the development of identification and quality evaluation of Dendrobium.

Enzymatic saccharification of corn stover can be enhanced by partially replacing commercial enzymes with bacterial crude enzyme extracts. Three bacteria, Bacillus sp. A0, Bacillus sp. CH20S1, and Exiguobacterium sp. AS2B, were cultured in a media with corn stover as the substrate. The cultural conditions were monitored and optimized to maximize CMCase and xylanase activity in the crude enzyme extracts. After 72 h of hydrolysis of corn stover with diluted crude enzymes (DCE) from the three strains, reducing sugars were released from non-pretreated and pretreated corn stovers. Values of the released sugars ranged from 48.23–71.69 mg g− 1, which were lower than those released by commercial cellulase (100–400 mg g− 1). The synergistic effects were observed when 12 FPU g− 1 and 4 FPU g− 1 of commercial cellulase were added to the DCE of the CH20S1 strain producing 315.90 mg g− 1 and 320.65 mg g− 1 reducing sugars, respectively. It was shown that an effective combination of bacterial DCE with commercial enzymes could achieve more cost-efficient saccharification of lignocellulosic biomass compared to either of the two enzymes used alone.

[Background] The key to integrated watershed management is to take simultaneous account of environmental, economic, and social development goals, hence, a multi-objective decision making approach is required. However, our understanding and application of multi-objective decision making in watershed management remains limited. [Objective] The objective of this study was to develop a multi-objective decision making system (MDMS) that could simultaneously handle multiple problems and objectives in a small watershed based on the relationships among land, water and economy. [Methods] The MDMS was coupled with the watershed hydrological model and economic benefit evaluation model to comprehensively simulate the watershed operational process, and established a multi-objective function to minimize sediment, nitrogen, and phosphorus outputs, while maximizing the economic benefits for integrated watershed management. The MDMS also utilized an improved meta-heuristic algorithm to optimize the agricultural land use structure of the small watershed to obtain the best integrated management plan at the small watershed scale. [Results] We found that the MDMS achieved seamless connections between automatic updating, analysis, and the optimization of land use structures in the iterative process, and successfully obtained an optimal scheme from a large number of agricultural land use structure alternatives, with particularly high time efficiencies. [Conclusions] Overall, the MDMS effectively controlled the negative impacts of crop planting on the environment, and simultaneously considered the economic benefits, which might assist managers in arriving at efficient scientific decisions toward the integrated management of small agricultural watersheds.

Shear strength is an important mechanical property of soil, as its mechanical function plays critical roles in reducing land degradation and preventing soil erosion. However, shear strength may be affected by vegetation type through changes in the soil and root patterns. To understand the influences of different types of vegetation on shear strength, the soil shear indices of three typical vegetation types (broad-leaved forest, coniferous broad-leaved mixed forest, and grassland) were studied and evaluated at the Fengyang Mountain Nature Reserve, China. We employed a direct shear apparatus to measure the soil shear resistance index. We quantified the soil porosity, moisture content, and composition of particle size to determine the properties of the soil, and a root scanner was used to quantify the root index. The results revealed that there were significant differences in shear resistance indices at the stand level. Between the three vegetation types, the internal friction angle of the broad-leaved forest was the largest and the cohesion was the smallest. The soil moisture content and porosity of the coniferous broad-leaved mixed forest were higher than those of the broad-leaved forest, and the root volume density (RVD/cm3) of the broad-leaved forest was higher than that of the coniferous and broad-leaved mixed forest and grassland. Structural equation modeling results show that the soil particle size and root characteristics indirectly impacted the soil water content by affecting porosity, which finally affected shear strength. In general, there were significant differences in soil properties and plant root indices between the different stands, which had an impact on soil shear strength.

Rainfall is an indispensable link in the atmospheric water cycle, which plays a critical role in forest hydrology. Quercus acutissima and Cunninghamia lanceolata are two fast-growing and economically important tree species in the middle and lower reaches of the Yangtze River. They are extensively applied in the restoration of vegetation, hydraulic engineering, and the development of artificial forests. The primary aims of this study were to describe and compare the changes in soil water content following rainfall events, while elucidating their relationships to environmental factors. From September 2012 to August 2013, we monitored the soil moisture at different depths every 30 min using commercially available soil moisture measuring devices. Hourly meteorological data were monitored over an open area at 200 m from the sample site, including photosynthetically active radiation (Par), air temperature (Ta), relative air humidity (RH), vapor pressure deficits (Vpd), rainfall, and wind speed. The results revealed that variations in the soil moisture content during summer (Cv = 0.231) and autumn (Cv = 0.0.170) were greater than during spring (Cv = 0.0.092) and winter (Cv = 0.0.055), with those in the deep soil moisture (Cv = 0.117) being smaller. The soil moisture content was significantly altered following the cessation of rainfall, where the initial and average moisture content, and the ACR of the soil increased with higher rainfall intensities. The ACR was positively correlated with Ta (γ = 0.16), RH (γ = 0.46) and rainfall (γ = 0.22), but negatively correlated with Par (γ = −0.29), Vpd (γ = −0.23), and wind speed (γ = −0.01). This study provides valuable information regarding the hydrological processes of artificial forests in the middle and lower reaches of the Yangtze River.

Anthropogenic overexploitation poses significant threats to the ecosystems that surround mining sites, which also have tremendous negative impacts on human health and society safety. The technological capacity of the ecological restoration of mine sites is imminent, however, it remains a challenge to sustain the green restorative effects of ecological reconstruction. As a promising and environmentally friendly method, the use of microbial technologies to improve existing ecological restoration strategies have shown to be effective. Nonetheless, research into the mechanisms and influences of rock-solubilizing microbial inoculums on plant growth is negligible and the lack of this knowledge inhibits the broader application of this technology. We compared the effects of rock-solubilizing microbial inoculums on two plant species. The results revealed that rock-solubilizing microbial inoculums significantly increased the number of nodules and the total nodule volume of Robinia pseudoacacia L. but not of Lespedeza bicolor Turcz. The reason of the opposite reactions is possibly because the growth of R. pseudoacacia was significantly correlated with nodule formation, whereas L. bicolor’s growth index was more closely related to soil characteristics and if soil nitrogen content was sufficient to support its growth. Further, we found that soil sucrase activity contributed the most to the height of R. pseudoacacia, and the total volume of root nodules contributed most to its ground diameter and leaf area. Differently, we found a high contribution of total soil carbon to seedling height and ground diameter of L. bicolor, and the soil phosphatase activity contributed the most to the L. bicolor’ s leaf area. Our work suggests that the addition of rock-solubilizing microbial inoculums can enhance the supply capacity of soil nutrients and the ability of plants to take up nutrients for the promotion of plant growth. Altogether, our study provides technical support for the practical application of rock-solubilizing microbes on bare rock in the future.

The general predictions of climate impacts on species shifts (e.g., upward shift) cannot directly inform local species conservation, because local-scale studies find divergent patterns instead of a general one. For example, our previous study found three shift patterns with elevation (strong down-, moderate down-, and up-slope shifts) in temperate mountain forests. The divergent shifts are hypothesized to arise from both multivariate environmental variations with elevation and corresponding species-specific responses. To test this hypothesis, we sampled soils and leaves to measure elevation variations in soil conditions and determined plant responses using discriminations against heavier isotopes, carbon (13 C) and nitrogen (15 N). Functional traits of the species studied were also extracted from a public trait dataset. We found that: (1) With low soil water contents at low elevations, only the leaves of up-shifters had lower 13 C discriminations at low vs. high elevations; (2) With low soil P contents at high elevations, only the leaves of moderate down-shifters had higher 15 N discriminations at high vs. low elevations; (3) The leaves of strong down-shifters did not show significant elevation patterns of the discriminations; (4) The contrasting responses among the three types of shifters agree with their functional dissimilarity, suggested by their separate locations in a multitrait space. Taken together, the divergent shifts are associated with the elevation variations in environmental conditions and contrasting plant responses. The contrasting responses could result from the functional dissimilarity among species. Therefore, a detailed understanding of both local environmental variations and species-specific responses can facilitate accurate predictions of species shifts to inform local species conservation.

Understanding how the biological invasion is driven by environmental factors will improve model prediction and advance early detection, especially in the context of accelerating anthropogenic ecological changes. Although a large body of studies has examined how favorable environments promote biological invasions, a more comprehensive and mechanistic understanding of invasive species response to unfavorable/stressful conditions is still developing. Grass invasion has been problematic across the globe; in particular, C4 grass invaders, with high drought tolerance, adaptations to high temperatures, and high water use efficiency, could become more severe. Here, we conducted a rigorous microcosm experiment, with one of the most damaging invasive C4 grass - cogongrass (Imperata cylindrica), to explore how cogongrass responds to soil water and nutrient stress. We further integrated the results of the microcosm study with a species distribution model to (1) corroborate greenhouse results with field observations and (2) validate the robustness of our findings at sub-continental scales. Both the microcosm experiments and species distribution model agreed that soil water stress had a stronger impact on cogongrass than the nutrient one. New vegetative growth of cogongrass continued to be inhibited by the prior water stress. The significant water effect on cogongrass total biomass was supported by the finding that both allometric and biochemical traits of cogongrass did not show significant responses to the changes in water treatment. Different to the conventional wisdom that nutrient enrichment plays a bigger role in facilitating biological invasions, this study highlighted the possibility that water conditions may have a more substantial effect on some aggressive invaders. Therefore, an important implication of this study on biological conservation is that field managers might take advantage of the negative effect of global drought on some invasive species to increase the efficiency of their controlling efforts because invasive species may become more vulnerable under drought effect.

Projecting invasion treatment outcomes and determining controlling efficiency under various management strategies have important implications in field management. Different from herbicide usage that may cause environmental pollution and nontarget effects on native plants, nonchemical (i.e., mechanical) methods, such as mowing and hand weeding, have shown great targeted effectiveness on invasion. However, an interesting and important question that remains unclear is how to reduce the need for repeated applications of mechanical treatments. One possible approach is to integrate mechanical treatments with biological control agents, which can attack and limit invasion spread after being established in the field. We hypothesize that applying mechanical methods to remove invasive plants while establishing biological control agents, then using the established biological control agents to limit future regrowth of invasive plants, will decrease the use of mechanical treatments. To include vegetation dispersal, we developed a spatial modeling framework, using paired logistic equation models of both a resident native plant and an invasive plant, and a biological control agent, to capture the dynamics of native and invasive plants under different treatment scenarios. Specifically, we examined four factors, the initial application location of biological agents, their controlling efficiency, the treatment frequency (how often nonchemical treatment will be applied), and the areal extent of mechanical treatment. We found that explicitly targeted biological control agents showed significantly stronger controlling impacts on invasive plants than did nontargeted agents, whereas a higher treatment frequency could compensate for the drawback of untargeted treatment. Our results also suggested that adding mechanical treatment can further limit invasion spread with the cooperation of established biological control agents, and applying mechanical treatment in a lower frequency, but treating larger areas per time, is a more efficient approach than vice versa. We emphasize that a high biological control efficiency can continuously decrease the requirement of repeated treatment of nonchemical methods and maintain the invasive population at a low level. The model we developed here can be potentially extended and used by field managers on prioritizing controlling efforts to achieve a higher efficiency.

Background Soil microbiomes play important roles in invasion biology, yet it is often treated as a ‘black box’ in modeling or large-scale field studies. Hence, investigating the change of association between invasive vegetation and soil microbes under changing environmental conditions, and exploring the genetic functions of associated microbiomes will provide a deeper understanding of invasion mechanisms. We performed a microcosm experiment with cogongrass (Imperata cylindrica (L.) P. Beauv.), which is one of the 100 worst invasive plants in the world. We combined rigorous sequencing analysis, including 16S rRNA, ITS, and shotgun metagenome sequencing, for the first time, to investigate the interactive effect of change in soil water and nutrient concentrations on microbiomes diversity, composition and genetic functions under invasion. Results We found that experimental drought has a stronger effect on the bacterial community than the fungal community. We discovered an enrichment of microbial groups, including Proteobacteria, Actinobacteria, Bacteroidetes and Chloroflexi under drought treatment, could likely contribute to invasion success. Further, we showed a striking trend of induction of cell wall, membrane and desiccation-related genes in drought treatment and a marked downregulation in regular treatment, which could create a more hydrated microenvironment, facilitating biofilm formation and better protection from desiccation.Conclusions Our work contributes to highlighting the associated microbial communities may have a potential long-term impact on increasing cogongrass drought resistance, ultimately, future invasion might be severe due to the plant-microbe interaction. These findings are important because current modeling practice, lacking comprehensive consideration of the plant-microbe interaction, could lead to a significant underestimate of predictions of future invasion patterns.

Development of suitable ecological protection and restoration policies for sustainable management needs to assess the potential impacts of future land use and climate change on ecosystem services. The two ecological shelters and three belts (TSTB) are significant for improving ecosystem services and ensuring China&rsquo, s and global ecological security. In this study, we simulated land use in 2050 and estimated the spatial distribution pattern of net primary productivity (NPP), water yield, and soil conservation from 2010 to 2050 under future climate change. The results showed that water yield, NPP, and soil conservation exhibited a spatial pattern of decreasing from southeast to northwest, while in terms of the temporal pattern, water yield and NPP increased, but soil conservation decreased. Water yield was mainly influenced by precipitation, NPP was affected by temperature and implementation of ecological restoration, and soil conservation was controlled by precipitation and slope. There was a strong spatial heterogeneity between trade-offs and synergies. In terms of the temporal, with the combination of climate change and ecological restoration, there was a synergistic relationship between water yield and NPP. However, the relationships between water yield and soil conservation, and between NPP and soil conservation were characterized by trade-offs. In the process of ecological construction, it is necessary to consider the differences between overall and local trade-offs and synergies, as well as formulate sustainable ecological management policies according to local conditions. Understanding the response of ecosystem services to future climate change and land use policies can help address the challenges posed by climate change and achieve sustainable management of natural resources.

The performance of direction-of-arrival (DOA) estimation is affected by the imprecise knowledge of the array shape. When a straight line array is towed by a ship, it is hard to keep the shape. Hence the shape of towed array must be estimated to avoid performance degradation. In this paper, we propose a new towed array shape estimation method combining eigenvector method of acoustic data with interpolation fitting method of heading data, and test its feasibility by experiment data conducted in the sea. Conventional beamforming (CBF) is performed for performance comparison of the traditional straight line assumption and the estimated shape, the results prove the effectiveness of the algorithm.

There are a large number of abandoned mining areas in China, where external-soil spray seeding is a common technique used to assist with the restoration of these areas. However, the soil component of external-soil spray seeding is deficient, and they are prone to collapse, which complicates ecological restoration. In this study, we added a mineral-solubilizing microbial strain to an external-soil spray seeding substrate in Robinia pseudoacacia and Lespedeza bicolor pots, which were monitored from December 2018 to November 2019. We investigated their root growth and root tensile properties, as well as root-reinforced soil shear strength. The results revealed that the addition of the microbial strain in the substrate improved root growth of Robinia pseudoacacia. The root-reinforced soil shear strength, tensile force and strength were also strengthened by the added microbial strain. Although the growth rate of Robinia pseudoacacia was faster than that of Lespedeza bicolor, the shear strength of the root-reinforced Robinia pseudoacacia soil was lower than that of the Lespedeza bicolor root-reinforced soil of the same diameter. Finally, compared with the cohesion, the change in the friction angle is relatively small, and differences in cohesion resulted in shear strength changes under the same treatment. Our results suggested that the addition of a mineral-solubilizing microbial strain to the external-soil spray seeding substrate could help plants strengthen the soil and positively enhance its effects. These results might also enrich the existing data on the effects of mineral-solubilizing microbial strains on plant roots, while guiding further studies toward improving the efficacy of external-soil spray seeding technologies.

Soil aggregates are the basic structural components of soil, which are important factors that can predict erosion resistance. However, few researchers have investigated the effects of forest conversion on the stability of soil aggregates, particularly in subtropical forests. In this study, soils from various depths (0 to 30 cm) were collected from four forest types (transformed from broadleaved forests (BMF) to combined coniferous broadleaved (CBMF), Chinese fir (FF), and bamboo forests (BF)) to determine the impacts of forest conversion on the physical and chemical properties of soil, water-stable soil aggregates, and aggregate-associated humic substances. The results showed that forest conversion had no effects on the soil’s physical properties, or the humic substances in bulk soil, but had significant effects on soil aggregates. In addition, the conversion of broadleaved forest to Chinese fir forest increased the soil stability, and to bamboo forest, decreased the soil stability. Finally, the soil’s physicochemical properties were closely related to aggregate-associated humic substances. In summary, specific forest management measures should be applied to strengthen the positive impacts and reduce the negative impacts associated with forest conversion.

Background Dendrobium huoshanense C.Z. Tang et S.J. Cheng is a traditional Chinese herbal medicine with high medicinal value in China. Polysaccharides and alkaloids are its main active ingredients. To understand the difference of main active ingredients in different tissues, we determined the contents of polysaccharides and alkaloids in the roots, stems and leaves of D. huoshanense. In order to explore the reasons for the differences of active ingredients at the level of transcription, we selected roots, stems and leaves of D. huoshanenese for transcriptome sequencing and pathway mining. Results The contents of polysaccharides and alkaloids of D. huoshanense were determined and it was found that there were significant differences in different tissues. A total of 716,634,006 clean reads were obtained and 478,361 unigenes were assembled by the Illumina platform sequencing. We identified 1407 carbohydrate-active related unigenes against CAZy database including 447 glycosyltransferase genes (GTs), 818 glycoside hydrolases (GHs), 60 carbohydrate esterases (CEs), 62 carbohydrate-binding modules (CBMs), and 20 polysaccharide lyases (PLs). In the glycosyltransferases (GTs) family, 315 differential expression genes (DEGs) were identified. In total, 124 and 58 DEGs were associated with the biosynthesis of alkaloids in Dh_L vs. Dh_S and Dh_R vs. Dh_L, respectively. A total of 62 DEGs associated with the terpenoid pathway were identified between Dh_R and Dh_S. Five key enzyme genes involved in the terpenoids pathway were identified, and their expression patterns in different tissues was validated using quantitative real-time PCR. Conclusions In summary, our study presents a transcriptome profile of D. huoshanense. These data contribute to our deeper relevant researches on active ingredients and provide useful insights into the molecular mechanisms regulating polysaccharides and alkaloids in Dendrobium. Electronic supplementary material The online version of this article (10.1186/s12864-018-5305-6) contains supplementary material, which is available to authorized users.

The brassinosteroids (BRs) constitute a recently defined class of plant hormone that can enhance the resistance of plants to multiple stresses. However, the effects of BRs on salt-stressed woody plants, notably on photosynthesis and chloroplast ultrastructure, have received little attention. Black locust (Robinia pseudoacacia L.) seeds and seedlings were pretreated with 1.04 µmol L− 1 24-epibrassinolide (24-epiBL) by soaking and root dipping, respectively, and grown under non-saline or saline conditions (0, 100, 200 mmol L− 1 NaCl). Salinity stress decreased photosynthesis, chlorophyll concentration, transpiration, and stomatal conductance but also decreased the water-use efficiency, while chlorophyll fluorescence indicated a decrease in photochemical quenching and in maximum potential quantum efficiency. Indicators of oxidative stress (for example, H2O2 and antioxidant enzymes), membrane leakage, and amounts of Na+ ions in leaves and chloroplasts were increased and, at the highest stress, chloroplast ultrastructure was severely disrupted. Exogenous 24-epiBL improved membrane stability and reduced foliar Na+ levels, while substantially alleviating stress-induced changes in photosynthetic gas exchange. Improvements in chlorophyll content and indicators of oxidative stress were not as large but were still highly significant. Thylakoid membrane structure was protected. Both methods of applying 24-epiBL were effective, but root-dipped seedlings performed marginally better. The results suggest that treatment of black locust seedlings with 24-epiBL prior to planting may improve performance and aid establishment on salt-affected soils.

Landslide susceptibility mapping (LSM) is a critical tool for mitigating the damages caused by geologic disasters. The selection of map units and mathematical models greatly affects the efficiency of LSM. To obtain the most appropriate combination of map units and mathematical models, four scales of catchment map units (CMUs) were analyzed and random forest (RF) and multivariate adaptive regression spline (MARSpline) models were applied in Gero City, Japan. The percentage of correctly identified landslides and the areas under the relative operating characteristic (ROC) curve were used to evaluate the model performances. The results indicate that the RF model had higher prediction accuracy than the MARSpline model, especially when the size of the CMU was 0.09 km2. A relatively high percentage of landslides fell into the high and very high landslide susceptibility classes (73%) and the lowest percentage of landslides fell into the very low landslide susceptibility classes (0.82%). The prediction-area (P-A) plots indicated that the prediction rates were higher for the RF model than the MARSpline model. The results of this study also suggest that the model accuracy can be increased if the appropriate CMU size is used. Therefore, the potential benefits of using the RF model in combination with the appropriate CMU size should be further explored using additional landslide-conditioning factors and other models.

Drought is one of the most critical limiting environmental factors for plant survival and restoration in areas of rocky desertification in southwestern China. Here, we aimed to understand how arbuscular mycorrhizal fungi (AMF) affect the growth and drought tolerance of tree species used for afforestation, with the ultimate aim of using them to restore degraded karst ecosystems. A pot experiment was conducted in which Zenia insignis seedlings were inoculated separately with three AMF (Funneliformis mosseae, Rhizoglomus intraradices, and Diversispora versiformis) and a mixture of all three species under two water regimes (drought stress and normal water) in a greenhouse. The results showed that AMF have a positive effect on plant biomass, osmolytes, and antioxidant enzyme activity under drought conditions. Shoot/root biomass increased by 12.5–33.8% and plant height increased by 13.6–32.1% after inoculation with AMF under drought conditions. The phosphorus content of the shoots significantly increased in mycorrhized plants, whereas nitrogen content was minimally affected. Superoxide dismutase and catalase activity was higher under drought stress in mycorrhized plants than in non-mycorrhized plants. The same pattern was found for soluble sugar and proline content in mycorrhized seedings under water deficit conditions. Mixed AMF inoculation had a more beneficial effect on plant growth than single AMF inoculation. In conclusion, our results indicate that AMF inoculation could help restore degraded ecosystems in desertified karst regions.

To find a multifunctional lignocellulolytic enzyme-producing strain, ten bacterial isolates from paper mill wastewater were tested for their carboxymethyl cellulose (CMC) hydrolytic ability. Bacillus sp. TPF-1, which exhibits the highest hydrolytic ability, was selected to produce lignocellulolytic enzymes using various biomass types as carbon sources. The highest CMCase (9.12 U/mL) and xylanase (102.55 U/mL) activities were obtained by green algae, and the maximum laccase activity (7037.28 U/L) was induced by Sargassum fusiforme. CMCase and xylanase showed the highest activities at 55 and 50 °C, respectively, with the same optimum pH of 5.4. The laccase exhibited optimum temperature of 40 °C and retained 60% more activity at 80 °C in extreme acid conditions (pH 2.2). To explore the multiple applications of these enzymes, crude enzymes induced by green algae were used to saccharify untreated algae. The reducing sugar produced by crude enzymes and commercial cellulase was 23 and 14% higher than that of the control, respectively, and it was 48% higher using crude enzymes with commercial cellulase (72 h). Additionally, the laccase induced by S. fusiforme was tested to decolorize two chemical dyes under an acidic condition (pH 2.2). The highest decolorization rates were 56.13 and 62.14% for Coomassie brilliant blue R-250 and Congo Red, respectively, in the presence of hydroxybenzotriazole monohydrate.

The influence of acid rain on forest trees includes direct effects on foliage as well as indirect soil-mediated effects that cause a reduction in fine-root growth. In addition, the concentration of NO3- in acid rain increases with the rapidly growing of nitrogen deposition. In this study, we investigated the impact of simulated acid rain with different SO42-/NO3- (S/N) ratios, which were 5:1 (S), 1:1 (SN) and 1:5 (N), on fine-root growth from March 2015 to February 2016. Results showed that fine roots were more sensitive to the effects of acid rain than soils in the short-term. Both soil pH and fine root biomass (FRB) significantly decreased as acid rain pH decreased, and also decreased with the percentage of NO3- increased in acid rain. Acid rain pH significantly influenced soil total carbon and available potassium in summer. Higher acidity level (pH=2.5), especially of the N treatments, had the strongest inhibitory impact on soil microbial activity after summer. The structural equation modelling results showed that acid rain S/N ratio and pH had stronger direct effects on FRB than indirect effects via changed soil and fine root properties. Fine-root element contents and antioxidant enzymes activities were significantly affected by acid rain S/N ratio and pH during most seasons. Fine-root Al ion content, Ca/Al, Mg/Al ratios and catalase activity were used as better indicators than soil parameters for evaluating the effects of different acid rain S/N ratios and pH on forests. Our results suggest that the ratio of SO42- to NO3- in acid rain is an important factor which could affect fine-root growth in subtropical forests of China.

Understanding the impacts of climate change and vegetation restoration on ecosystem services is essential for sustainable ecosystem management. However, the characteristics of nonlinear impacts of climate change and vegetation change on ecosystem services are still unclear, especially the determination of their impact thresholds. The Qinghai-Tibet Plateau ecological shelter (QPES) was chosen as the study area. The changes in precipitation, temperature, fractional vegetation cover (FVC) and ecosystem services (water yield, net primary productivity (NPP) and soil conservation) were analyzed, the impacts of climate and vegetation cover changes on ecosystem services were evaluated, and the thresholds were quantitatively identified. The results showed that annual mean precipitation increased from 2000 to 2014 and dropped sharply in 2015, with temperatures rising significantly (p

Labile fractions of soil carbon pools are sensitive to environmental changes, which would influence the stabilization of soil carbon. However, it is unclear whether the dynamics of labile organic carbon (LOC) and soil organic carbon (SOC) are coupled and how they influence each other in coastal wetland. The present work investigated the trends of soil carbon fractions among mangrove and Spartina alterniflora communities with different stand ages (1, 5, 10, and 15 years), at Quanzhou Bay Estuary Wetland Nature Reserve, China. We found that SOC in a mangrove ecosystem increased over time, while there was no significant trend in S. alterniflora dominated ecosystems. The highest LOC of mangrove appeared in 5-year-old communities, and then decreased with stand age. In S. alterniflora communities, content of labile fractions increased with the stand age. These trends indicated different soil carbon dynamics when comparing mangrove and S. alterniflora ecosystems. The development of mangroves promoted accumulation of recalcitrant carbon, while S. alterniflora ecosystems contributed to an increase of labile carbon. This phenomenon is probably caused by the characteristics of vegetation and the hydrological conditions. Mangroves contribute more refractory organic carbon to the soil carbon pool, while accumulation of LOC in S. alterniflora communities may inhibit the stabilization of SOC. Our study on the relationship of LOC and SOC implies that complex interactions occur among soil carbon pools and environmental conditions in coastal wetlands, suggesting soil carbon models should take into account decoupled dynamics of LOC and SOC.

Ecosystem service value (ESV) is greatly affected by changes in land use/land cover (LULC), and land use decisions are critical drivers of LULC change. ESV assessment has become an important basis for evaluating the effectiveness of land use decisions. The implementation location and scope of different land use decisions have not received sufficient research attention, and there is therefore little information on the actual effects of such decisions. Northeast China has been the subject of multiple land use decisions in the past, and a lack of information on their effectiveness has created challenges to sustainable ecosystem management. In this study, we used the latest benefit transfer method specifically developed for China to evaluate the changes in ESV and quantified the location and scope of different land use decisions to evaluate their benefits. The results showed that the total ESV increased from about $353.54 billion in 2000 to $354.86 billion in 2010 because of the expansion of river and lake, broad-leaved forest, and paddy field. However, the total ESV decreased to $353.39 billion in 2015 due mainly to decreases in wetlands, rivers and lakes, and dry farmland. The impact of wetland loss on ESV outweighed that of forestland increase. The Grain for Green Program (GFGP) and the Natural Forests Conservation Program (NFCP) increased ESV in the 2000–2010 period but decreased it in the 2010–2015 period. The Three-North Shelterbelt Program (TNSP) led to a continuous increase in ESV, but the Natural Wetland Conservation Program (NWCP) did not lead to an increase in ESV from 2000 to 2015. The effectiveness of the GFGP, NFCP, and NWCP should be enhanced, and priority conservation areas need to be established. This study can provide a reference for balancing the influence of multiple land use decisions in order to promote sustainable development.

A new honeycomb-like 2D Metal-organic polyhedral framework, {Cu3.75(BrCPEIP)2.5·(H2O)2.75·DMF}n (NJFU-5, H3BrCPEIP ​= ​5-((3-bromo-5-carboxyphenyl)ethynyl)isophthalic acid) was solvothermally synthesized and structurally characterized, which shows a BET surface area of 473 ​m2 ​g−1. Meanwhile, NJFU exhibits a comparably higher CO2 adsorption capacity of 37.0 ​cm3 ​g-1 (4.6 ​wt%) at 1 ​bar and 298 ​K in 2D MOF family, and a high CO2 selective adsorption toward N2 and CH4 as well.

Implementing the policy of returning farmland to lakes (RFL) led to land use/land cover (LULC) changes and affected ecosystem service trade-offs. Consequently, the implementation intensity of RFL has become an important issue. The LULC of the Jianghuai Ecological Economic Zone (JHEEZ) has transformed significantly because of the implementation of RFL. In this study, we simulated the LULC change of the JHEEZ in 2030 and then analyzed the trade-offs and synergies of ecosystem services under four RFL intensity scenarios. Our results showed that water yield first increased and then decreased, and crop production decreased; in contrast, carbon storage, habitat quality, and water purification continuously increased. The levels of the five ecosystem services were most balanced in the mild RFL scenario. In this scenario, water yield and crop production decreased by 0.46% and 5.95%, respectively. In contrast, carbon storage, habitat quality, and water purification increased by 0.35%, 3.49% and 3.20%, respectively. Under the moderate and strong RFL scenarios, increases in regulation services were at the expense of significant reductions in supply services. In all RFL scenarios, carbon storage, habitat quality and water purification increased in synergy, except for natural RFL scenarios. These three ecosystem services were in a trade-off relationship with water yield and crop production. However, under the natural RFL scenario, water yield was synergistic with these three ecosystem services. Therefore, the implementation of RFL may enhance ecosystem service trade-offs. Our results reveal the impact of different intensities of RFL on ecosystem service trade-offs and suggest that the intensity of RFL implementation should be factored into policy making and ecosystem management. This study can provide a useful reference for decision makers to choose the optimal restoration intensity of lake and wetland.

Acid rain is mainly caused by dissolution of sulfur dioxide and nitrogen oxides in the atmosphere, and has a significant negative effect on ecosystems. The relative composition of acid rain is changing gradually from sulfuric acid rain (SAR) to nitric acid rain (NAR) with the rapidly growing amount of nitrogen deposition. In this study, we investigated the impact of simulated SAR and NAR on litter decomposition and the soil microbial community over four seasons since March 2015. Results first showed that the effects of acid rain on litter decomposition and soil microbial were positive in the early period of the experiment, except for SAR on soil microbes. Second, soil pH with NAR decreased more rapidly with the amount of acid rain increased in summer than with SAR treatments. Only strongly acid rain (both SAR and NAR) was capable of depressing litter decomposition and its inhibitory effect was stronger on leaf than on fine root litter. Meanwhile, NAR had a higher inhibitory effect on litter decomposition than SAR. Third, in summer, autumn and winter, PLFAs were negatively impacted by the increased acidity level resulting from both SAR and NAR. However, higher acidity level of NAR (pH = 2.5) had the strongest inhibitory impact on soil microbial activity, especially in summer. In addition, Gram-negative bacteria (cy19:0) and fungi (18:1ω9) were more sensitive to both SAR and NAR, and actinomycetes was more sensitive to SAR intensity. Finally, soil total carbon, total nitrogen and pH were the most important soil property factors affecting soil microbial activity, and high microbial indices (fungi/bacteria) with high soil pH. Our results suggest that the ratio of SO 4 2 − to NO 3 − in acid rain is an important factor which could affect litter decomposition and soil microbial in subtropical forest of China.

In this study, we investigated the effect of forest types changes (from coniferous and broadleaf mixed forest (CBMF) to plantation forests of bamboo (Phyllostachys pubescens forest, MBF) and hickory (Carya cathayensis forest, CHF)) combined with intensive management on soil organic carbon (SOC) and microbial community structure, using the 13C-nuclear magnetic resonance (NMR) and phospholipid fatty acid (PLFA). The results indicated that soil organic carbon significantly decreased by 30.7 and 28.5% in MBF and CHF, respectively. The aromatic C and aromaticity also significantly decreased in MBF and CHF (P 0.05). Significant changes of the soil microbial community were found after the forest type changed from CBMF to MBF and CHF. Total soil microbial PLFAs, soil bacteria PLFAs, fungus PLFAs, actinobacteria PLFAs, arbuscular mycorrhizal fungi PLFAs and protozoan PLFAs ranked as follows: CBMF > CHF > MBF (P CHF (0.66) > CBMF (0.49) (P CHF > MBF, P

The soil and water loss in rock mining areas is an extremely serious problem, while microbes play significant roles in soil remediation of those areas. In this study, a fungal strain Gongronella sp. NF-15 was isolated from the abandoned dolostone mines, and its mechanism of promoting dolostone dissolution was explored by analyzing the changes of pH value, Ca 2+ concentration, Mg 2+ concentration, organic acid concentration, micromorphology of rock surface, and rock particle diameter under controlled experimental conditions. After incubation of strain NF-15 with dolostone, the pH value continuously decreased significantly within 15 d, while the concentrations of Ca 2+ and Mg 2+ rose rapidly (1.8–2.7 times higher than that of control group). High performance liquid chromatography (HPLC) analysis showed that organic acids (succinic acid, citric acid, oxalic acid, malic acid, and lactic acid) were secreted by the strain NF-15 in the process of dolostone dissolution, and succinic acid was found more effective than other organic acids in lowering the pH and accelerating dissolution of rocks by Pearson correlation and Structural Equation Model (SEM) path analysis. In addition, the ultrastructure observation of the rock exhibited the significant erosion by fungal hyphae. Thus, strain NF-15 was suggested to combine with environmental remediation technologies to solve the problems of thin soil layer and mineral deficiency in destroyed dolostone mines. These results not only enrich the available microbial resources but also provide a new strategy for rehabilitating abandoned land in rock mining areas.

Carbonate minerals are extensively distributed across China, and their special rock structures make them vulnerable to land damage through mining, leading to rocky desertification. Soil microorganisms play an important role in mineral weathering. However, little is known about the utilization of the mineral-weathering microorganisms to alleviate the problem of rocky desertification in mines. In the present study, the mineral-solubilizing bacterium NL-11 was isolated from soil around weathered dolostones and identified as Bacillus thuringiensis (B. thuringiensis) based on the Biolog identification system and 16S rDNA sequence analysis. The mineral dissolution experiments revealed that inoculation with the live bacterium significantly increased the mineral sample dissolution via significantly enhancing Ca and Mg release, with increase values of 303.27 and 50.55 mg·L-1, respectively, compared to that with the inactivated bacterium. Moreover, the acetic acid secreted by strain NL-11 markedly decreased the size of particle diameter (quantified with a laser diffraction particle size analyser) through reducing pH value. The eroded traces were observed by scanning electron microscopy (SEM) analysis, and the results further verified the erosional effects of this strain. In addition, this bacterium contributed to the establishment and proliferation of plants by providing nutrient elements, such as phosphorus (P) and potassium (K). Our study not only provided an efficient bacterial strain NL-11, but also enriched the technologies to mitigate problems associated with ecological restorations of carbonate mines.

본 연구는 루머 유형(음모성/오염성), 메시지 소구 유형(이성/감성)을 독립변인으로 하고 수용자의 정보 처리동기(높다/낮다)를 조절변인으로 하여, 루머 신뢰, 확산 의도 및 반박 확산 의도에 미치는 영향을 살펴보았다. 연구를 위해 2(루머 유형) × 2(메시지 소구 유형) × 2(수용자의 정보 처리 동기)의 개체 간 실험이 설계되었다. 이를 통해 루머 내용이 무엇인가(What to say), 그리고 메시지를 구성되는 소구 방식이 어떠한가(How to say)에 따라 사람들의 확산 의도 등이 달라지는지 알아보고자 했다. 연구 결과를 보면, 먼저, 음모성 루머보다 오염성 루머에 관한 수용자의 루머 신뢰와 반박 확산 의도가 더욱 높게 나타났다. 이는 기업 입장에서 소비자에게 직접적인 해를 줄 수 있는 오염성 루머를 보다 적극적으로 대처할 필요성을 의미한다. 또한, 이성적 소구보다는 감성적 소구 메시지에 대한 루머 신뢰와 확산 의도가 낮고 반박 확산 의도가 높음을 확인하였다. 특히 오염성 루머일 때는 이성적 소구 방식이 루머 신뢰가 높고 반박 확산 의도가 낮았다. 개인의 정보 처리 동기도 모든 종속변인에서 유의미한 주효과를 보였다. 마지막으로, 세 변인 간의 상호작용 효과는 확산의도를 제외한 루머 신뢰와 반박 확산 의도에서 발견되었다. 구체적으로 정보 처리 동기가 낮은 경우, 감성적 소구 방식일 때 오염성 루머보다는 음모성 루머에 관한 수용자 루머 신뢰가 높고 반박 확산 의도가 낮게나타났으며, 이성적 소구 방식일 때는 이와 반대로 음모성 루머보다 오염성 루머에 관한 사람들의 루머 신뢰가 높고 반박 확산 의도가 낮았다. 본 연구는 그간의 루머 연구들이 주목하지 않았으나 중요한 고려 대상이될 수 있는 루머 유형과 루머의 소구 형태, 그리고 수용자의 특성 등에 초점을 맞추어 루머 연구의 폭을 넓히는 데 기여했다.

The distribution of species and communities in relation to environmental heterogeneity is a central focus in ecology. Co‐occurrence of species with similar functional traits is an indication that communities are determined in part by environmental filters. However, few studies have been designed to test how functional traits are selectively filtered by environmental conditions at local scales. Exploring the relationship between soil characteristics and plant traits is a step toward understanding the filtering hypothesis in determining plant distribution at local scale. Toward this end, we mapped all individual trees (diameter >1 cm) in a one‐ha subtropical forest of China in 2007 and 2015. We measured topographic and detailed soil properties within the field site, as well as plant leaf functional traits and demographic rates of the seven most common tree species. A second one‐ha study plot was established in 2015, to test and validate the general patterns that were drawn from first plot. We found that variation in species distribution at local scale can be explained by soil heterogeneity and plant functional traits. (From first plot). (1) Species dominant in habitats with high soil ammonium nitrogen and total phosphorus tended to have high specific leaf area (SLA) and relative growth rate (RGR). (2) Species dominant in low‐fertility habitats tended to have high leaf dry matter content (LDMC), ratio of chlorophyll a and b (ratioab), and leaf thickness (LT). The hypothesis that functional traits are selected in part by environmental filters and determine plant distribution at local scale was confirmed by the data of the first plot and a second regional site showed similar species distribution patterns.

Based on a new V-shaped tetracarboxylic ligand with a methoxyl group, a new mfj-type microporous metal–organic framework [Cu6(MBDPB)3(H2O)6]·12DMF·10H2O (NJFU-3, NJFU for Nanjing Forestry University; H4MBDPB for 5-methoxyl-1,3-bis(3,5-dicarboxylphenyl)-benzene) was successfully synthesized and structurally characterized. With moderately high porosity, appropriate pore aperture and unsaturated metal sites, the activated NJFU-3a exhibits high H2 (2.56 wt% at 77 K and 1 bar) and CO2 uptakes (15.8 wt% at 298 K and 1 bar), and a moderately high CH4 storage capacity of 155 cm3 cm−3 at 35 bar and 298 K. Meanwhile, it shows a comparably high delivery amount of 135 cm3 cm−3 when taking 5 bar as a specific lower pressure limit and 65 bar as the upper limit.

A new methyl-embedded (3,36)-connected txt-type metal–organic framework, {Cu2(DCPEMP)·H2O}n (NJFU-4, H4DCPEMP = 3,5-bis(3,5-dicarboxylphenylethynyl)-4-methylpyridine), was solvothermally synthesized and structurally characterized, which exhibits a BET surface area of 2160 m2 g−1, high stability and high H2 uptake capacity (2.61 wt% at 1 bar and 77 K).

Background and AimsThe protective effects of arbuscular mycorrhizal fungi (AMF) on salt-stressed crop plants had been well studied. However, the physiological mechanism of AMF in mitigating adverse impact caused by salinity stress in different tissues of woody plants is not clear. Gleditsia sinensis Lam. is a valuable tree species with various phamaceutical uses; however, high soil NaCl concentration limits its growth in saline soil including coastal areas. This study aimed to investigate the effects of AMF on G. sinensis salinity tolerance and reveal its underlying physiological mechanism.MethodsA greenhouse experiment was performed. G. sinensis seedlings with and without AMF inoculation were subjected to four salinity levels (0, 50, 100, and 150 mM NaCl). After 2 months, the seedlings were harvested and analyzed for growth and biochemical parameters.ResultsHigh AMF colonization rates (over 95%) and high mycorrhizal dependency (over 75%) were observed across all NaCl levels, and AMF-inoculated plants presented significantly higher aboveground and below ground growth than non-inoculated plants. AMF effectively enhanced the salinity tolerance of G. sinensis seedlings by enhancing leaf gas exchanges inducing higher leaf net photosynthetic rates; improving peroxidase, catalase, and superoxide dismutase activities resulting in higher membrane stability indexes and lower malondialdehyde contents in leaves and roots; increasing P uptake and P/N ratio to mitigate P-limited biomass products; selectively absorbing less Na + and more Ca 2+ in their tissues to alleviate ion toxicity and maintain more favorable ion balances (e.g., K + /Na + ) in their tissues.ConclusionsThe results suggested the feasibility of using AMF to improve salinity tolerance as well as afforestation and rehabilitation of G. sinensis in coastal areas.

Dendrobium officinale is a kind of crop and precious herbal that is widely distributed in China. We applied transcriptomics to investigate the flavonoids and their biosynthesis-related genes from different tissues. Total flavonoid was determined in three different tissues. In this study, nine cDNA libraries were generated from Dendrobium officinale. A total of 530 million (70.73%) of the high-quality reads were successfully mapped to the reference genome of Dendrobium officinale and nine libraries were combined and assembled into 24,927 non-redundant genes. We mapped all of these genes to reference pathways in the KEGG database to identify polysaccharide and secondary metabolites pathways in which the genes may be involved. We outlined the biosynthetic pathway of flavonoids and identified putative genes, which provide understanding of the biosynthesis and regulation of Dendrobium officinale flavonoids at the molecular level. We identified five CHS genes from Dendrobium officinale and characterized the CHS gene family. The flavonoid-related key enzyme genes were identified, and their expression patterns in different tissues were further analyzed using quantitative real-time PCR. These data on flavonoid genes obtained in this work will be useful in understanding the molecular mechanisms of different tissues in Dendrobium officinale.

Background Dendrobium moniliforme (Linnaeus) Swartz is a well-known plant used in traditional Chinese medicine due to bioactive constituents. Polysaccharides are the main medicinal ingredients, yet no studies have been published on polysaccharide biosynthesis in D. moniliforme. To comprehensively investigate the polysaccharide at the transcription level, we performed de novo transcriptome sequencing for the first time to produce a comprehensive transcriptome of D. moniliforme. Results In our study, a database of 562,580 unigenes (average length = 1115.67 bases) was generated by performing transcriptome sequencing. Based on the gene annotation of the transcriptome, we identified 1204 carbohydrate-active related unigenes against CAZy database, including 417 glycosyltransferase genes (GTs), 780 glycoside hydrolases (GHs), 19 carbohydrate esterases (CEs), 75 carbohydrate-binding modules (CBMs), and 44 polysaccharide lyases (PLs). In the cellulose synthase family, 21 differential expression genes (DEGs) related to polysaccharide were identified. Subsequently, the tissue-specific expression patterns of the genes involved in polysaccharide pathway were investigated, which provide understanding of the biosynthesis and regulation of DMP at the molecular level. The two key enzyme genes (Susy and SPS) involved in the polysaccharide pathway were identified, and their expression patterns in different tissues were further analyzed using quantitative real-time PCR. Conclusions We determined the content of polysaccharides from Dendrobium moniliforme under different tissues, and we obtained a large number of differential genes by transcriptome sequencing. This database provides a pool of candidate genes involved in biosynthesis of polysaccharides in D. moniliforme. Furthermore, the comprehensive analysis and characterization of the significant pathways are expected to give a better insight regarding the diversity of chemical composition, synthetic characteristics, and the regulatory mechanism which operate in this medical herb.