Search

Acid rain and nitrogen deposition are emerging as global scale environmental issues due to increasing industrial emissions and agricultural pollutants, which seriously impac t the sustainable development of global ecosystems. However, the specific effects both acid rain and nitrogen deposition interactions on forest soil ecosystems, particularly as relates to the soil nutrient content and enzyme activities, remain unclear. Therefore, we established a simulated sample plot of acid rain (SR, NR) and nitrogen deposition (N) and their interactions (SRN, NRN) in a subtropical Cunninghamia lanceolata (C. lanceolata) plantation in the Yangtze River Delta region of China to investigate the impacts of these factors via correlation analysis and structural equation model (SEM). The results showed that acid rain had a stronger effect on soil pH than nitrogen deposition in C. lanceolata plantation, while the simultaneous addition of acid rain and nitrogen deposition exacerbated soil acidification. Soil available potassium, ammonium nitrogen and nitrate nitrogen in C. lanceolata plantation responded more obviously to acid rain and nitrogen deposition, in which acid rain, nitrogen deposition and their interactions significantly reduced soil available potassium content, while acid rain and nitrogen deposition interactions significantly increased soil ammonium nitrogen and nitrate nitrogen content. Nitric acid rain, nitrogen deposition and their interactions significantly increased soil NAGase activity, but significantly decreased soil urease activity; the single-factor treatment of acid rain and nitrogen deposition significantly increased soil arylsulfatase activity, while the interaction of acid rain and nitrogen deposition significantly decreased soil arylsulfatase activity; in general, the interaction of acid rain and nitrogen deposition had a stronger effect on the soil ecosystem of the C. lanceolata plantation than that of single acid rain or nitrogen deposition, of which nitrogen deposition exacerbated the effects of acid rain on the soil ecosystem of C. lanceolata plantation mainly by changing the soil pH and the content of effective nutrients.

IntroductionThe stability of exposed slopes is prone to natural disasters, seriously threatening socio-economic and human security. Through years of exploration and research, we proposed an active permanent greening (APG) method based on patented mineral solubilizing microorganisms (MSMs) as an improvement over the traditional greening method.MethodsIn this study, we selected two MSMs (Bacillus thuringiensis and Gongronella butleri) and a plant species (Lolium perenne L.) set up six treatments (T1, T2, T3, T4, T5, and T6) to investigate the effectiveness of the MSMs and their combinations with the plant species on the soil stability using APG method.ResultsWe noted that both MSMs and the plant species significantly improved soil aggregate stability and organic matter content. Of all the treatments, the T1 treatment exhibited better results, with soil aggregate stability and organic matter content increased to 45.63% and 137.57%, respectively, compared to the control. Soil stability was significant positively correlated with macroaggregate content and negatively with microaggregates. Using structural equation modeling analysis, we further evaluated the mechanism underpinning the influence of organic matter content and fractions on the content of each graded agglomerates. The analysis showed that the macroaggregate content was influenced by the presence of the plant species, primarily realized by altering the content of organic matter and aromatic and amide compounds in the agglomerates, whereas the microaggregate content was influenced by the addition of MSMs, primarily realized by the content of organic matter and polysaccharide compounds. Overall, we observed that the effect of the co-action of MSMs and the plant species was significantly better than that of using MSMs or the plant species alone.DiscussionThe findings of this study provide reliable data and theoretical support for the development and practical application of the APG method to gradually develop and improve the new greening approach.

IntroductionWith social and economic development and the associated large-scale exploitation of natural resources, the number of slopes has significantly increased. As slope instability can lead to serious geological disasters, the ecological protection and reconstruction of slopes has become a hot topic of common global concern.MethodsIn order to achieve scientific slope management and overcome the difficulty of maintaining slope greening in the long term, this study explored eight strategies (A, B, C, AB, AC, BC, ABC, CK), involving different patented mineral solubilizing microorganisms (MSMs), and analyzed the field application of active permanent greening (APG) based on MSMs.ResultsThe results revealed that MSMs significantly increased the content of effective metal ions and available nutrients in soil and enhanced soil enzyme activity. Among all strategies, strategy A showed significant superiority, with soil effective calcium, magnesium, potassium, nitrogen, phosphorus and organic matter contents increasing by 51.62%, 55.41%, 30.42%, 39.77%, 181.69% and 76.92%, respectively, while urease, sucrase and peroxidase activities increased by 89.59%, 74.68% and 85.30%. MSMs strongly promoted the growth of Amorpha. Strategy A showed the best performance, with plant seedling height, ground diameter, leaf area, root length, and root volume increasing by 95.75%, 47.78%, 124.14%, 108.83%, and 139. 86%, respectively. According to a comprehensive evaluation using the entropy-analysis hierarchy process, strategy A has great potential for application. The field test results verified that APG has significantly better greening performance than the traditional greening method, with high vegetation cover and stable soil layer.DiscussionThe results of this study provide a reliable practical basis and technical reference for the development, promotion, and application of APG.

IntroductionSalinization affects more than 25% of the world's arable land, and Tamarix ramosissima Ledeb (T. ramosissima), the representative of Tamarix plants, is widely grown in salinized soil. In contrast, less is known about the mechanism of potassium's antioxidative enzyme activity in preventing NaCl stress damage to plants.MethodThis study examined changes in root growth for T. ramosissima at 0h, 48h, and 168h, performed antioxidant enzyme activity assays, transcriptome sequencing, and non-targeted metabolite analysis to understand changes in their roots as well as changes in the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). Quantitative real-time PCR (qRT-PCR) was used to identify differentially expressed genes (DEGs) and differential metabolites associated with antioxidant enzyme activities.ResultAs the time increased, the results showed that compared with the 200 Mm NaCl group, the root growth of the 200 mM NaCl + 10 mM KCl group increased, the activities of SOD, POD and CAT increased the most, but the contents of hydrogen peroxide (H2O2) and Malondialdehyde (MDA) increased less. Meanwhile, 58 DEGs related to SOD, POD and CAT activities were changed during the application of exogenous K+ for 48h and 168h in T. ramosissima. Based on association analysis of transcriptomic and metabolomic data, we found coniferyl alcohol, which can act as a substrate to label catalytic POD. It is worth noting that Unigene0013825 and Unigene0014843, as POD-related genes, have positively regulated the downstream of coniferyl alcohol, and they have a significant correlation with coniferyl alcohol.DiscussionIn summary, 48h and 168h of exogenous K+ applied to the roots of T. ramosissima under NaCl stress can resist NaCl stress by scavenging the reactive oxygen species (ROS) generated by high salt stress by enhancing the mechanism of antioxidant enzyme activity, relieving NaCl toxicity and maintaining growth. This study provides genetic resources and a scientific theoretical basis for further breeding of salt-tolerant Tamarix plants and the molecular mechanism of K+ alleviating NaCl toxicity.

Abstract Microbial weathering processes can significantly promote soil properties and reduce 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 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, 15 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 reports a potential bacterial based approach for improving the ecological restoration of over-exploited rock mining sites. Graphical Abstract

Abstract Background Soil acidification caused by acid rain (AR) can damage plant roots, which in turn negatively impacts plant health. In response to changing AR types, research efforts to elucidate their specific impacts on plants have become intense. Methods For this study, we investigated the effects of simulated sulfuric, nitric, and mixed AR on the root systems of Quercus acutissima Carr. and Cunninghamia lanceolata (Lamb.) Hook. under different acidity levels. Results As the AR S/N ratio and pH decreased, the height growth rate (HGR), basal diameter growth rate (DGR), total root length (TRL) and total root surface area (TRS) of C. lanceolata decreased, whereas the TRL and TRS of Q. acutissima remained the same. When the NO3 − concentration in AR was increased, the root activity, superoxide dismutase (SOD) and catalase (CAT) activities of C. lanceolata roots revealed a downward trend; however, the root activity of Q. acutissima and the peroxidase (POD) activity of C. lanceolata roots revealed an upward trend. Further, redundant analysis and structural equation models indicated that AR pH had a greater impact on the HGR of Q. acutissima than that of C. lanceolata, while the impact of the AR S/N ratio on C. lanceolata growth rates was greater than that of Q. acutissima. Conclusions Our results suggested that the root systems of different tree species had variable responses to AR, and the AR S/N ratio was an important factor affecting plant root growth. This might facilitate new strategies for the cultivation and protection of plantations in the future.

Introduction: In this study, Poly (trimethylene carbonate)/Doxycycline hydrochloride (PTMC/DH) films were introduced to repair the Achilles tendon defects for the first time.Methods: (PTMC/DH) films with different DH content of 10, 20, and 30% (w/w) were prepared by solvent casting. The in vitro and in vivo drug release of the prepared PTMC/DH films was investigated.Results: The results of drug release experiments showed that the PTMC/DH films released effective concentrations of doxycycline for more than 7 and 28 days in vitro and in vivo, respectively. The results of antibacterial activity experiments showed diameters of 25.00 ± 1.00 mm, 29.33 ± 1.15 mm, and 34.67 ± 1.53 mm, respectively, for the inhibition zones produced by the release solutions of PTMC/DH films with 10, 20 and 30% (w/w) DH at 2 h, indicating that the drug-loaded films could inhibit Staphylococcus aureus well. After treatment, the Achilles tendon defects have recovered well, as indicated by the more robust biomechanical properties and the lower fibroblast density of the repaired Achilles tendons. Pathology revealed that the pro-inflammatory cytokine, IL-1β, and the anti-inflammatory factor, TGF-β1, peaked in the first three days and gradually decreased as the drug was released more slowly.Discussion: These results demonstrated that the PTMC/DH films have great potential for regenerating Achilles tendon defects.

Abstract 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 (SO4 2−/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 SO4 2−/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.

Abstract The biological pretreatment for the enzymatic hydrolysis of lignocellulosic biomasses depends exclusively on the effective pretreatment process. Herein, we report a significant enhancement of enzymatic saccharification obtained with corn stover using a bacterial strain 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 as well as other enzymes 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 a 20-day 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 of commercial cellulase, the yield of reducing sugar released from 20-day 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.

Assessment of soil quality in different vegetation types of wetland ecosystems is essential for soil functioning, such as nutrient cycling and vegetation growth, particularly the maintenance of wetland ecosystem sustainability. Wetland degradation can extremely influence soil quality. However, prediction of soil quality in terms of soil quality index in wetland soils remains obscure. In this study with the fundamental goal to assess soil quality, we have intended to assemble a range of soil quality indicators to characterize the soil quality index (SQI). The minimum data set (MDS) from the Principal component analysis (PCA) was used to determine the SQI. With such objectives, three vegetation types: Robinia pseudoacacia community (tree), Tamarix chinensis community (bush), and Suaeda salsa community (grass) were selected in the Yellow River Delta wetland, eastern of China. A total of 108 soil samples [3 sites (tree, bush and grass)—3 field plots—3 replicates—4 soil depth layers: 0–10 cm, 10–20 cm, 20–40 cm, and 40–60 cm] were collected for laboratory analyses. This study showed that there were high variations in soil physical and chemical properties among the three sites. Soil organic carbon (SOC), silt, clay, and pH at tree site, total soil porosity (TSP), soil organic carbon (SOC), pH, and soil bulk density (SBD) at bush site, and total soil porosity (TSP), silt, and soil electronic conductivity (SEC) at grass site were retained in the MDS. SOC and TSP were the key soil quality indicators. The values of the SQI at 0–10 cm soil depth at all three sites (2.236, 0.895, and 2.573 respectively) were the highest compared with other soil depths, indicating the best soil quality in the upper soil layers (0–10 cm). The values of the SQI at 0–10 cm soil depth at both tree site and grass site were similar, and they were higher than those at bush site. At tree site, the values of the SQI decreased with increasing soil depth, which indicated that soil quality became worse with depth. At bush site, the values of the SQI decreased with increasing soil depth (0–40 cm), while the values increased at 40–60 cm depth, indicating better soil quality in the deeper soil layers (40–60 cm). At grass site, the values of the SQI at 10–20 cm and 40–60 cm soil depth were lower than those at 20–40 cm soil depth, indicating better soil quality at 20–40 cm soil depth. It is concluded that the SQI can be compared more accurately in different vegetation types of wetland ecosystems based on its simplicity and quantitative flexibility. These findings are of importance because the assessment of the SQI allows to quantify different vegetation effects on soil quality.

Understanding impacts of land use/cover (LULC) and climate change ecosystem services (ESs) is critical to human well-being. However, existing studies seldom determined the relative contributions of LULC and climate change to ESs from a geospatial perspective, and the impacts of different LULC conversions on ESs remain unclear. This study established a framework for distinguishing the relative spatial contributions of climate and LULC change to water yield, net primary productivity (NPP) and soil retention and applied it to Zhejiang Province. The results showed that all ESs showed an increasing trend from 2000 to 2020. Changes in water yield and soil retention were dominated by climate change, accounting for 75.22% and 77.69% of the total study area, respectively, while the changes in NPP were dominated by LULC changes, accounting for 82.70% of the total study area. We further quantified the impact of three major forms of LULC changes (urbanization, deforestation, and afforestation) on ESs in their respective regions. Deforestation and urbanization reduced NPP by 192 gC/m2 and 115.75 gC/m2, respectively, while afforestation increased NPP by 220.10 gC/m2. Afforestation reduced the water yield by 84.27%, while deforestation and urbanization increased it by 37.94% and 62.42%, respectively. Deforestation reduced soil retention by 38.28%, while urbanization and afforestation increased it by 3.91% and 63.28%, respectively. Five suggestions for improving ES management were proposed based on our results. This study can provide a detailed reference for decision-makers seeking sustainable ecosystem management strategies.

Achilles tendon injury has become a common sports injury clinically, and its treatment and rehabilitation are essential, while the regenerative capacity of the Achilles tendon in adult mammals is limited. Therefore, it is necessary to promote the repair and remodelling of the Achilles tendon through efficient interventions. Biodegradable polymer materials are one of the most popular in the treatment and repair of soft tissues, ligaments, muscles, and organs injured by organisms to enhance the function of their wounded sites. Thus, it plays a specific role in “compensation” and is widely used in clinical medicine and rehabilitation. This review summarized the progress of poly (ε-caprolactone), polylactic acid, poly (lactic-co-glycolic acid), poly (trimethylene carbonate) (PTMC), and polydioxanone (PDS) in repairing Achilles tendon injury, indicating that the biodegradable polymers have succeeded in improving and treating Achilles tendon injuries. However, some problems such as lack of good affinity with cells and uncontrollable degradation of the biodegradable polymers should be overcome in repairing Achilles tendon injury. Therefore, the development of modified biodegradable polymers to make them an ideal repair material that meets the requirements is vital in improving Achilles tendon injuries. With the continuous development and close cooperation of life sciences and material sciences, excellent materials for repairing Achilles tendon injuries will undoubtedly be produced. The treatment of Achilles tendon injuries will be more straightforward, which will be a boon for many athletes.

Microbial inoculants can be used to restore abandoned mines because of their positive effects on plant growth and soil nutrients. Currently, soils in greenhouse pot studies are routinely sterilized to eradicate microorganisms, allowing for better inoculant colonization. Large-scale field sterilization of abandoned mining site soils for restoration is difficult, though. In addition, microbial inoculants have an impact on plants. Plants also have an impact on local microbes. The interactions among microbial inoculants, native microorganisms, and plants, however, have not been studied. We created a pot experiment utilizing the soil and microbial inoculant from a previous experiment because it promoted plant growth in that experiment. To evaluate the effects of the plants, native microorganisms, and microbial inoculants, we assessed several indicators related to soil elemental cycling and integrated them into the soil multifunctionality index. The addition of the microbial inoculant and sterilizing treatment had a significant impact on alfalfa growth. When exposed to microbial inoculant treatments, the plant and sterilization treatments displayed radically different functional characteristics, where most of the unsterilized plant treatment indices were higher than those of the others. The addition of microbial inoculant significantly increased soil multifunctionality in plant treatments, particularly in the unsterilized plant treatment, where the increase in soil multifunctionality was 260%. The effect size result shows that the positive effect of microbial inoculant on soil multifunctionality and unsterilized plant treatment had the most significant promotion effect. Plant and native microorganisms amplify the positive effects of microbial inoculant.

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.

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.

There is a serious problem with soil salinization that affects the growth and development of plants. Tamarix ramosissima Ledeb (T. ramosissima), as a halophyte, is widely used for afforestation in salinized soils. At present, there are few reports on the antioxidant mechanism of T. ramosissima under NaCl stress. In this study, we learned about the superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities, and hydrogen peroxide (H2O2) and malondialdehyde (MDA) content changes in T. ramosissima. We also mined the relevant metabolic pathways in the antioxidant mechanism, candidate key genes, and their related differential metabolites and verified them using quantitative real-time PCR (qRT-PCR). The results show that the SOD, POD, and CAT activities, and the H2O2 and MDA content reached the highest values in the roots of T. ramosissima. Simultaneously, 92 differentially expressed genes (DEGs) related to antioxidant enzyme activities changed during 48 and 168 h of NaCl stress, and these DEGs were mainly upregulated in 168 h. Based on the association analysis of transcriptomic and metabolomic data, we found Unigene0089358 and Unigene0007782 as genes related to key enzymes in the flavonoid biosynthesis pathway. They were located in the upstream positive regulation at 48 and 168 h under NaCl stress, and their respective related metabolites (phloretin and pinocembrin) were involved in resistance to NaCl stress, and they were significantly correlated with their respective metabolites. In conclusion, at 48 and 168 h under NaCl stress, the roots of T. ramosissima resist NaCl stress by enhancing enzymatic and nonenzymatic antioxidant mechanisms, scavenging ROS generated by high-salt stress, alleviating NaCl toxicity, and maintaining the growth of T. ramosissima. This study provides genetic resources and a scientific theoretical basis for further breeding of salt-tolerant Tamarix plants and the molecular mechanism of antioxidants to alleviate NaCl toxicity.

Abstract 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.

Low and dynamic duty cycles cause that the E2E delay for packet delivery is more critical in energy-harvesting wireless sensor networks (EH-WSNs). The traditional routing protocols are constrained by the in-technology communication paradigm, where Wi-Fi devices can talk to the Wi-Fi devices only, and so on for ZigBee or wireless technology. This is, however, not necessary by recent advances in cross-technology communication (CTC). The CTC enables ZigBee nodes to be coordinated by a Wi-Fi node without any hardware changes or gateway equipment, which sheds the light on more efficient routing protocols design. In this paper, we introduce a new routing protocol based on a CTC technique called RowBee. RowBee takes the advantages of coordination from the Wi-Fi node to assist the ZigBee nodes for establishing routing paths and allows nodes to choose their duty cycles freely with finer duty-cycle granularity. A simple yet effective method is employed so that the ZigBee nodes are coordinately waked up simultaneously according to the beacons broadcasted by the Wi-Fi nodes. We implement RowBee based on a USRP-N210 and MICAz hybrid platform, and the experimental results show that RowBee can reduce the E2E delay greatly.

Pine wilt disease is a devastating forest disease caused by the pinewood nematode Bursaphelenchus xylophilus, which has been listed as the object of quarantine in China. Climate change influences species and may exacerbate the risk of forest diseases, such as the pine wilt disease. The maximum entropy (MaxEnt) model was used in this study to identify the current and potential distribution and habitat suitability of three pine species and B. xylophilus in China. Further, the potential distribution was modeled using the current (1970–2000) and the projected (2050 and 2070) climate data based on two representative concentration pathways (RCP 2.6 and RCP 8.5), and fairly robust prediction results were obtained. Our model identified that the area south of the Yangtze River in China was the most severely affected place by pine wilt disease, and the eastern foothills of the Tibetan Plateau acted as a geographical barrier to pest distribution. Bioclimatic variables related to temperature influenced pine trees’ distribution, while those related to precipitation affected B. xylophilus’s distribution. In the future, the suitable area of B. xylophilus will continue to increase; the shifts in the center of gravity of the suitable habitats of the three pine species and B. xylophilus will be different under climate change. The area ideal for pine trees will migrate slightly northward under RCP 8.5. The pine species will continue to face B. xylophilus threat in 2050 and 2070 under the two distinct climate change scenarios. Therefore, we should plan appropriate measures to prevent its expansion. Predicting the distribution of pine species and the impact of climate change on forest diseases is critical for controlling the pests according to local conditions. Thus, the MaxEnt model proposed in this study can be potentially used to forecast the species distribution and disease risks and provide guidance for the timely prevention and management of B. xylophilus.

Ecosystems are severely damaged with rising global temperatures, the rapid increase in population and the continuous exploitation and utilization of natural resources. The selection of conservation priorities is of great significance to regional ecological security and sustainable development. Here we identified conservation priorities by balancing ecosystem services trade-offs and analyzed the spatiotemporal changes in ecosystem services. Water yield, soil conservation, carbon storage, habitat quality, and ecological recreation were quantified using the InVEST model. By comparing conservation efficiencies under each scenario, we found the conservation efficiencies of the conservation priorities for water yield, soil conservation, habitat quality, carbon storage, and ecological recreation to be 1.05, 1.76, 1.30, 1.37 and 1.41, respectively. The conservation efficiencies of ecosystem services were consistently greater than 1 during the years 2000–2015. The implementation of the Grain-for-Green Programme and increased rainfall have improved ecosystem services and our results are of great significance to regional ecological and environmental protection and the improvement of ecosystem services.

To protect endangered species and restore their habitats, it is important to be able to predict their potential geographic distributions. The Dendrobium plant is important in traditional Chinese medicine, but urban expansion and over-exploitation have led to a decrease of Dendrobium resources. To achieve sustainable development of Dendrobium resources, the spatial and temporal distribution of two Dendrobium species were systematically analyzed based on the distribution points of D. moniliforme (104) and D. nobile (87). Maximum entropy modeling (MaxEnt) was used to predict the distribution of suitable habitats for these Dendrobium species, both currently and in the future, under different representative concentration pathways (RCPs). Three RCPs included RCP2.6, RCP4.5, and RCP8.5. The results show that D. moniliforme and D. nobile are widely distributed in the south of China (Anhui, Guangdong, Jiangxi, and Hunan provinces). Worldwide, Japan and North Korea were identified as major distribution areas for D. moniliforme and D. nobile. Based on the MaxEnt model, the mean diurnal range and the minimum temperature of the coldest month were identified as the most significant bioclimatic variables controlling the distribution of D. moniliforme and D. nobile. Future climate change will likely result in an increase of suitable habitat areas for D. moniliforme (by around 16%), and a decrease for D. nobile (by around 1–10%), but climate change is unlikely to have much impact on the distribution of suitable habitats for D. moniliforme and D. nobile in Japan and North Korea. Based on our findings, measures should be taken to protect these precious medicinal plant resources, and the sites used for the artificial cultivation of Dendrobium will need to shift as the climate changes.

Background The distribution and use of camphor (Cinnamomum camphora L.) trees are constrained by increasing soil salinity in south-eastern China along the Yangtze River. However, the response mechanism of this species to salinity, especially in team of photosynthesis, are unknown. Methods Here, we analysed themorphological, physiological, ultrastructural, and proteomic traits of camphor seedlings under NaCl (103.45 mM) treatment in pot experiments for 80 days. Results The growth was limited because of photosynthetic inhibition, with the most significant disturbance occurring within 50 days. Salinity caused severe reductions in the leaf photosynthetic rate (An), stomatal conductance (gs), maximal chlorophyll fluorescence (Fm), maximum quantum yield of PSII (Fv/Fm), non-photochemical quenching (NPQ), relative quantum efficiency of PSII photochemistry (ΦPSII), photochemical quenching coefficient (qP) and photo-pigment contents (chlorophyll a (Cha), chlorophyll b (Chb), total chlorophyll (Chl)); weakened the antioxidant effects, including those of malondialdehyde (MDA), superoxide dismutase (SOD) and peroxidase (POD); and injured chloroplasts. The physiologicalresults indicated that the main reason for photo-inhibition was oxidative factors induced by NaCl. The proteomic results based on isobaric tags for relative and absolute quantitation (iTRAQ) further confirmedthat photosynthesis was the most significant disrupted process by salinity (P

Although microorganisms play a key role in the carbon cycle of the Poyang Lake wetland, the relationship between soil microbial community structure and organic carbon characteristics is unknown. Herein, high-throughput sequencing technology was used to explore the effects of water level (low and high levels above the water table) and vegetation types (Persicaria hydropiper and Triarrhena lutarioriparia) on microbial community characteristics in the Poyang Lake wetland, and the relationships between soil microbial and organic carbon characteristics were revealed. The results showed that water level had a significant effect on organic carbon characteristics, and that soil total nitrogen, organic carbon, recombinant organic carbon, particle organic carbon, and microbial biomass carbon were higher at low levels above the water table. A positive correlation was noted between soil water content and organic carbon characteristics. Water level and vegetation type significantly affected soil bacterial and fungal diversity, with water level exerting a higher effect than vegetation type. The impacts of water level and vegetation type were higher on fungi than on bacteria. The bacterial diversity and evenness were significantly higher at high levels above the water table, whereas an opposite trend was noted among fungi. The bacterial and fungal richness in T. lutarioriparia community soil was higher than that in P. hydropiper community soil. Although both water level and vegetation type had significant effects on bacterial and fungal community structures, the water level had a higher impact than vegetation type. The bacterial and fungal community changes were the opposite at different water levels but remained the same in different vegetation soils. The organic carbon characteristics of wetland soil were negatively correlated with bacterial diversity but positively correlated with fungal diversity. Soil water content, soluble organic carbon, C/N, and microbial biomass carbon were the key soil factors affecting the wetland microbial community. Acidobacteria, Alphaproteobacteria, Verrucomicrobia, Gammaproteobacteria, and Eurotiomycetes were the key microbiota affecting the soil carbon cycle in the Poyang Lake wetland. Thus, water and carbon sources were the limiting factors for bacteria and fungi in wetlands with low soil water content (30%). Hence, the results provided a theoretical basis for understanding the microbial-driven mechanism of the wetland carbon cycle.

Abstract 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.

Dendrobium, an important medicinal plant, is a source of widely used herbal medicine to nourish the stomach and treat throat inflammation. The present study is aimed at distinguishing and evaluating three major Dendrobium species by comparing physiochemical characteristics and understanding differences between different growth years in the Ta-pieh Mountains. Polysaccharides and total alkaloids of Dendrobium were determined, and the amino acids and trace elements were determined by UPLC (Ultra High-Performance Liquid Chromatography) and ICP-MS (Inductively coupled plasma mass spectrometry). It can be seen from the results that the polysaccharide content of these three kinds of Dendrobium in different growth years ranges from 249.31 mg·g-1 to 547.66 mg·g-1, and the highest content is in the 3-year-old Dendrobium huoshanense. The total alkaloid content ranges from 0.21 mg·g-1 to 0.54 mg·g-1, and the highest content is also the 3-year-old Dendrobium huoshanense. We determined the amino acid content of these three Dendrobium in different growth years, and we can see that each of the three kinds of Dendrobium contain seven kinds of amino acids required by the human body. We conducted a safety evaluation of the essential trace elements of Dendrobium, and the results showed that the dosage of 12g·d-1 Dendrobium prescribed in China Pharmacopoeia is in accordance with the recommended daily intake of trace elements recommended by the Food and Drug Administration of the United States, and will not cause trace element poisoning. Linear discriminant analysis was carried out on the basis of amino acids and trace elements and confirmed the applicability of multi-elemental analysis for identifying different Dendrobium species.

Background: Myeloperoxidase (MPO) anti-neutrophil cytoplasm autoantibody (ANCA)-associated vasculitis commonly causes life-threatening pulmonary alveolar hemorrhage or fibrosis. Only a limited number of candidate gene variants have been explored, but hitherto, are not widely confirmed. In the present study, we investigated the importance of energy homeostasis associated gene (Enho) mutations and adropin deficiency in the development of MPO-ANCA associated lung injury. Methods: We analyzed the peripheral blood mononuclear cells from 152 unrelated patients and 220 population-matched healthy individuals for genetic variations in Enho. Functional studies with adropin knockout (AdrKO) on C57BL/6J mice were also performed. Findings: Sequencing revealed six patients with p.Ser43Thr and that five patients shared Cys56Trp amino acid substitution in Enho. Serum concentration of adropin was significantly lower in patients than that of the healthy subjects (P

A predicted impact of a warming climate is an upslope shift of montane plant species. These upslope shifts may be amplified by land-use changes or attenuated by forest recoveries at low elevations where historical disturbances were ceased allowing for plant regrowth. Consequently, species may shift downslope back to low elevations where they had been previously harvested. The cessation-driven downslope shifts are hypothesized to dampen or even reverse climate-driven upslope shifts. We tested this hypothesis by a 20 year (1989–2009) forest inventory dataset from five mountainous areas in eastern China. In our study region, intense deforestation occurred mostly at low elevations until 1970, but was then ceased to facilitate natural forest recovery. Based on the analyses of 30 216 woody plants in 609 plots, we found that: (1) forest recovery occurred over the 20 year survey period, and increment rates of both recruitment and basal area increased up to 2004. However, in the last period (2004–2009), increment rates of basal area leveled off and recruitment was close to zero; (2) forest recovery was faster at lower elevations, as indicated by the higher increment rates there; (3) despite rising regional temperatures, the mean elevations of study species showed a downslope shift over the 20 years; and (4) the contribution of forest recovery to elevational shifts was supported by the fact that the species shifts were positively related to elevational changes in the recruitment increment, e.g. the negative (or downslope) shifts occurred in association with higher increments at lower elevations. These results suggest that, the cessation of disturbances and consequent lowland forest recovery had greater effects on the species distributions than did warming climate. In mountain systems that are being allowed to recover from historical disturbances, the effects of forest recovery on species distributions should be explicitly accounted for when assessing and predicting climate change impacts.

Chinese hickory (Carya cathayensis), a popular nut food tree species, is mainly distributed in southeastern China. A field study was carried out to investigate the effect of long-term intensive management on fertility of soils under a C. cathayensis forest. Results showed that after 26 years’ intensive management, the soil organic carbon (SOC) content of the A and B horizons reduced by 19% and 14%, respectively. The reduced components of SOC are mainly the alkyl C and O-alkyl C, whereas the aromatic C and carbonyl C remain unchanged. The reduction of active organic matter could result in degradation of soil fertility. The pH value of soil in the A horizon had dropped by 0.7 units on average. The concentrations of the major nutrients also showed a decreasing trend. On average the concentrations of total nitrogen (N), phosphorus (P), and potassium (K) of tested soils dropped by 21.8%, 7.6%, and 13.6%, respectively, in the A horizon. To sustain the soil fertility and C. cathayensis production, it is recommended that more organic fertilizers (manures) should be used together with chemical fertilizers. Lime should also be applied to reduce soil acidity.

Introduction: The stability of exposed slopes is prone to natural disasters, seriously threatening socio-economic and human security. Through years of exploration and research, we proposed an active permanent greening (APG) method based on patented mineral solubilizing microorganisms (MSMs) as an improvement over the traditional greening method. Methods: In this study, we selected two MSMs (Bacillus thuringiensis and Gongronella butleri) and a plant species (Lolium perenne L.) set up six treatments (T1, T2, T3, T4, T5, and T6) to investigate the effectiveness of the MSMs and their combinations with the plant species on the soil stability using APG method. Results: We noted that both MSMs and the plant species significantly improved soil aggregate stability and organic matter content. Of all the treatments, the T1 treatment exhibited better results, with soil aggregate stability and organic matter content increased to 45.63% and 137.57%, respectively, compared to the control. Soil stability was significant positively correlated with macroaggregate content and negatively with microaggregates. Using structural equation modeling analysis, we further evaluated the mechanism underpinning the influence of organic matter content and fractions on the content of each graded agglomerates. The analysis showed that the macroaggregate content was influenced by the presence of the plant species, primarily realized by altering the content of organic matter and aromatic and amide compounds in the agglomerates, whereas the microaggregate content was influenced by the addition of MSMs, primarily realized by the content of organic matter and polysaccharide compounds. Overall, we observed that the effect of the co-action of MSMs and the plant species was significantly better than that of using MSMs or the plant species alone. Discussion: The findings of this study provide reliable data and theoretical support for the development and practical application of the APG method to gradually develop and improve the new greening approach. [ABSTRACT FROM AUTHOR]