Distribution Characteristics and Restoration Application of Vegetation in Chengcun Bay Surrounding Areas of Yangjiang City

In recent years, global warming and sea level rise have further aggravated the risk of coastal erosion. Coastal vegetation plays an important role in resisting storm surges and alleviating coastal erosion. Therefore, screening plant species for the purpose of constructing ecological seawalls to protect or repair damaged coastal zones has become a hot issue. In this paper, a field survey was conducted to investigate the vegetation in Chengcun Bay surrounding areas of Yangjiang City by combining a line survey and sample plot survey. By understanding the vegetation types, distribution and community structure in the bay’s surrounding areas and analyzing the restricting environmental factors of those plants, we put forward some countermeasures for coastal vegetation restoration in difficult site conditions from the aspects of plant species selection, vegetation configuration and restoration technology, so as to provide reference for ecological vegetation restoration in similar locations

Physiological and Photosynthetic Characteristics with Ecological Restoration Application of Nerium indicum Under Salt Stress

Marine salinity affects mainly the roots, stems and leaves of coastal plants through groundwater intrusion, splashing and salt spray. Two-year-old Nerium indicum L. seedlings with good growth were used to carry out the salt tolerance experiments in their roots and leaves by setting multiple concentration gradients of control 0%, 0.3%, 0.6%, 1.0%, 2.0% and 3.0%. Normal watering for 4 weeks was followed by 13 weeks of salt stress treatment. The net photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductance (Gs) and water use efficiency (WUE) were measured at the end of salt stress and after normal irrigation. At the same time, physical and chemical indices, such as the cell membrane permeability and water saturation deficit (WSD) of leaves, were measured. The results showed that both soil salt stress and foliar salt stress affected the morphology and growth of Nerium indicum. When the soil salt stress was ≥1.0%, the growth status of Nerium indicum decreased irreversibly to less than 2, while under foliar salt stress ≤3.0%, the growth status of Nerium indicum was generally greater than 2. Soil salt stress significantly reduced the Pn, Tr and Gs of Nerium indicum leaves. Foliar salt stress had significant effects on Pn and WUE but no significant effects on Tr and Gs. There was a significant correlation between Tr and Gs; under high-concentration soil salt stress, stomatal factors had a more significant effect on the photosynthesis of Nerium indicum. Under foliar salt stress, the cell membrane permeability and WSD of Nerium indicum did not change significantly. Under high-concentration soil salt stress, the cell membrane permeability and WSD of Nerium indicum changed irreversibly, corresponding well with the results of growth status and photosynthetic responses, indicating that the damage to the membrane system in turn affected the growth and photosynthesis of Nerium indicum. In general, Nerium indicum can tolerate less than 3.0% foliar salt stress and less than 1.0% soil salt stress. Studying the salt tolerance characteristics of roots and leaves can provide theoretical guidance for the application of Nerium indicum in coastal ecology and vegetation restoration

The Transcriptional Repressor PerR Senses Sulfane Sulfur by Cysteine Persulfidation at the Structural Zn²⁺ Site in <i>Synechococcus</i> sp. PCC7002

Cyanobacteria can perform both anoxygenic and oxygenic photosynthesis, a characteristic which ensured that these organisms were crucial in the evolution of the early Earth and the biosphere. Reactive oxygen species (ROS) produced in oxygenic photosynthesis and reactive sulfur species (RSS) produced in anoxygenic photosynthesis are closely related to intracellular redox equilibrium. ROS comprise superoxide anion (O2●−), hydrogen peroxide (H2O2), and hydroxyl radicals (●OH). RSS comprise H2S and sulfane sulfur (persulfide, polysulfide, and S8). Although the sensing mechanism for ROS in cyanobacteria has been explored, that of RSS has not been elucidated. Here, we studied the function of the transcriptional repressor PerR in RSS sensing in Synechococcus sp. PCC7002 (PCC7002). PerR was previously reported to sense ROS; however, our results revealed that it also participated in RSS sensing. PerR repressed the expression of prxI and downregulated the tolerance of PCC7002 to polysulfide (H2Sn). The reporter system indicated that PerR sensed H2Sn. Cys121 of the Cys4:Zn2+ site, which contains four cysteines (Cys121, Cys124, Cys160, and Cys163) bound to one zinc atom, could be modified by H2Sn to Cys121-SSH, as a result of which the zinc atom was released from the site. Moreover, Cys19 could also be modified by polysulfide to Cys19-SSH. Thus, our results reveal that PerR, a representative of the Cys4 zinc finger proteins, senses H2Sn. Our findings provide a new perspective to explore the adaptation strategy of cyanobacteria in Proterozoic and contemporary sulfurization oceans

Distribution Characteristics and Main Control Measures of Spartina alterniflora in Mainland China

The rapid invasion and spread of Spartina alterniflora will cause great damage to the ecological environment of the invasive areas. Spartina alterniflora is widely distributed in coastal areas from north to south of China, which seriously reduces the biodiversity and ecological barrier function of the coastal zone. The main control methods of Spartina alterniflora invasion in China include physical, chemical and biological control. At present, the single control methods, such as mowing, crushing and burying, and cofferdam flooding, can effectively control the invasion of Spartina alterniflora in small areas, but the control effect of large areas or patches is not good. Based on the analysis and comparison of the existing control methods, combined with the practical experience of scientific research, this paper put forward a comprehensive control method of Spartina alterniflora suitable for different areas of China, which combined the physical control method, chemical control method and biological control method

The Transcriptional Repressor PerR Senses Sulfane Sulfur by Cysteine Persulfidation at the Structural Zn2+ Site in Synechococcus sp. PCC7002

Cyanobacteria can perform both anoxygenic and oxygenic photosynthesis, a characteristic which ensured that these organisms were crucial in the evolution of the early Earth and the biosphere. Reactive oxygen species (ROS) produced in oxygenic photosynthesis and reactive sulfur species (RSS) produced in anoxygenic photosynthesis are closely related to intracellular redox equilibrium. ROS comprise superoxide anion (O2&#9679;&minus;), hydrogen peroxide (H2O2), and hydroxyl radicals (&#9679;OH). RSS comprise H2S and sulfane sulfur (persulfide, polysulfide, and S8). Although the sensing mechanism for ROS in cyanobacteria has been explored, that of RSS has not been elucidated. Here, we studied the function of the transcriptional repressor PerR in RSS sensing in Synechococcus sp. PCC7002 (PCC7002). PerR was previously reported to sense ROS; however, our results revealed that it also participated in RSS sensing. PerR repressed the expression of prxI and downregulated the tolerance of PCC7002 to polysulfide (H2Sn). The reporter system indicated that PerR sensed H2Sn. Cys121 of the Cys4:Zn2+ site, which contains four cysteines (Cys121, Cys124, Cys160, and Cys163) bound to one zinc atom, could be modified by H2Sn to Cys121-SSH, as a result of which the zinc atom was released from the site. Moreover, Cys19 could also be modified by polysulfide to Cys19-SSH. Thus, our results reveal that PerR, a representative of the Cys4 zinc finger proteins, senses H2Sn. Our findings provide a new perspective to explore the adaptation strategy of cyanobacteria in Proterozoic and contemporary sulfurization oceans

The Effect of Domestic Sewage Treatment on Islands Using Ecological Treatment Processes: A Case Study of Haimen Island, Fujian Province

Islands are characterized by a lack of land and freshwater resources, public finances, and technical personnel. As a result, domestic sewage may not be effectively treated, which can lead to major pollution on islands and in the surrounding sea areas. In this study, a pilot treatment of domestic sewage was conducted using an ecological treatment process (i.e., a constructed wetland and ecological pond) in an abandoned pond located on Haimen Island, Fujian Province, China. The pollutant indicators were monitored to analyze this treatment method at different treatment stages. The results showed that the combination of multiple ecological treatment processes had favorable treatment effects on various pollutants in the sewage. The treatment rates of the chemical oxygen demand (CODCr) and suspended solids (SS) surpassed 88%. The treatment rate of the biochemical oxygen demand (BOD5), ammonia nitrogen (NH3-N), total nitrogen (TN), total phosphorus (TP), and fecal coliform surpassed 93%, and all the indicators met or were close to the level I B emission standards for urban sewage treatment plants. Different treatment stages have different treatment effects on different pollutants. The constructed wetland played an important role in sewage treatment through plant absorption, substrate adsorption, sedimentation, and microbial decomposition, particularly for the TP, CODCr, and BOD5. In contrast, algal photosynthesis in the ecological pond produced a large amount of dissolved oxygen, and the treatment effect was highest for the TN and NH3-N. The treatment effects on the fecal coliform in the constructed wetland and ecological pond were very significant. Ecological treatment processes based on the combination of a constructed wetland and ecological pond have favorable treatment effects, low construction and maintenance costs, and pollution-free conditions, which are suitable for application in island areas

Synergistic CO2 Removal via Enhanced Olivine Weathering and Diatom Growth in the Ocean

Enhancing the alkalinity of the ocean is a promising approach for CO2 removal by promoting marine carbon sequestration. Olivine is a key candidate material for enhancing alkalinity owing to its release of silicates when dissolved in seawater. These released compounds serve as crucial nutrients for phytoplankton such as diatoms to foster their growth, which in turn accelerates olivine dissolution and further enhances carbon sequestration. In this study, we investigated the short-term synergistic CO2 removal effects of an olivine–diatom coculture system. Over a 6-day incubation period, the olivine dissolution was 92% to 144% higher in the olivine–diatom groups compared with the olivine-only groups. The olivine-only groups achieved a CO2 removal efficiency of 5.15% to 5.49%, while the olivine–diatom groups achieved a CO2 removal efficiency of 8.84% to 14.44%. Adding olivine was found to increase the total alkalinity by 70 to 100 μM and the diatom abundance by 26.4% to 58.4%. Diatom growth and the fixed carbon content were greatly enhanced, particularly during the later silicate-depleted stage when the Si:C ratio significantly exceeded that of groups without olivine. This mutually beneficial olivine–diatom coculture system offers a highly efficient CO2 removal strategy for addressing climate change. The results of this study contribute to our understanding of carbonate and biological carbon pump processes

Comparison of bacterioplankton communities in three mariculture ponds farming different commercial animals in subtropical Chinese coast

In order to explore the responses of the bacterioplankton community to different types of aquaculture environments, three mariculture ponds comprised of groupers (Epinephelus diacanthus, ED), prawns (Penaeus vannamei, PV), and abalone (Haliotis diversicolor supertexta, HDS) in southeast, coastal China were investigated. The free-living bacterial diversity was analyzed through the construction of 16S rDNA clone library. A total of 203 16S rDNA sequences from three clone libraries were classified into 118 operational taxonomic units (OTUs), of which 51, 31, and 42 OTUs were distributed in the ED, PV, and HDS pond, respectively, with Bacteroidetes (30.6%), Actinobacteria (55.2%), and Cyanobacteria (32.8%) as the dominant division in the respective ponds. Meanwhile, each pond occupied some unique OTUs that were affiliated with uncommon (sub-) phyla, such as candidate OP11 division, Acidobacteria, Deltaproteobacteria, Planctomycetes, and Verrucomicrobia. Bacterial diversity in the ED pond was the richest, followed by the HDS and the PV pond. OTUs of 61.9% and 94.9% have less than 90% and 97% similarity to their nearest neighbors in public databases, respectively. All OTUs were grouped into 67 clusters, covering 11 (sub-) phyla. The OTUs only from single pond distributed in 53 clusters (79.1%), the OTUs shared by two ponds were affiliated with 14 clusters (20.9%), and none of clusters was formed by the OTUs which commonly originated from the three pond libraries, suggesting that the composition of bacterial populations in these ponds were significantly different. These results indicate that the aquatic environment created by different mariculture animals may foster very special and complex bacterial communities.NSFC [40632013, 40521003]; MOST [200805068, 2006BAC11B04

A multicenter single‐arm trial of neoadjuvant pyrotinib and trastuzumab plus chemotherapy for HER2‐positive breast cancer

Abstract The objective of this multicenter, single‐arm trial (ChiCTR1900022293) was to explore the efficacy and safety of neoadjuvant therapy with epirubicin, cyclophosphamide, and pyrotinib followed by docetaxel, trastuzumab, and pyrotinib (ECPy‐THPy) in the treatment of patients with stage II–III HER2‐positive breast cancer. The present study enrolled patients with stage II–III HER2‐positive breast cancer. Epirubicin and cyclophosphamide were administrated for four 21‐day cycles, followed by four cycles of docetaxel and trastuzumab. Pyrotinib was taken orally once per day throughout the treatment period. The primary endpoint was total pathological complete response (tpCR, ypT0/is ypN0) rate in the modified intention‐to‐treat (mITT) population. In total, 175 patients were included. The tpCR rate was 68.6% (95% CI, 60.7–75.8%), while the objective response rate was 89.1%. In the post‐hoc subgroup analysis, no association between clinical characteristics and the tpCR rate was observed. The most common grade ≥3 adverse events were diarrhea (54.3%), followed by white blood cell count decreased (5.1%), and neutrophil count decreased (4.6%). In conclusion, the neoadjuvant regimen with ECPy‐THPy showed promising pathological response and clinical benefits with an acceptable safety profile in patients with stage II–III HER2‐positive breast cancer

Bacterial diversity in various coastal mariculture ponds in Southeast China and in diseased eels as revealed by culture and culture-independent molecular techniques

Mariculture ponds are widely distributed in Chinese coasts and have become a threat to the health of coastal ecosystems. In order to improve our understanding on the microbial composition in mariculture environments, we sampled a variety of ponds farming different animals or plants around the Dongshan Island and Xiamen Island in Southeast China and isolated cultures from the tissues of diseased eels. Analysis by polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE), clone library and direct culturing methods revealed highly diverse bacterial communities in these samples. Bacterial communities in the Dongshan samples were dominated by Alphaproteobacteria, Gammaproteobacteria and Bacteroidetes. The Gracilaria verrucosa pond harbours the most abundant species (20 DGGE bands), followed by Epinephelus diacanthus pond (18 bands), Haliotis diversicolor supertexta pond I (18 bands) and Penaeus vannamei pond (11 bands). In comparison with surface waters, Penacus orientalis pond sediment showed a much more complex bacterial community, from which only sequences affiliated with Deltaproteobacteria, Firmicutes, Acidobacteria and candidate phylum TM6 were found. Bacterial cultures in diseased eels were closely related to two pathogenic genera, Aeromonas in Gammaproteobacteria and Bacillus, in Firmicutes. Clones affiliated with another two genera, Escherichia and Vibrio, that have pathogenic potentials were also identified. Phylogenetic analysis of a total of 131 sequences showed that 48.9% of the sequences were clustered into Gammaproteobacteria and formed the most abundant group, followed by Alphaproteobacteria (19.1%), Firmicutes (7.6%), Bacteroidetes (5.3%), Deltaproteobacteria (5.3%), Actinobacteria (4.6%), Chloroplast (3.8%), Acidobacteria (2.3%), Cyanobacteria (1.5%), Betaproteobacteria (0.7%) and TM6 (0.7%). 43.7% (28/64) of the phylogenetic clusters cannot be classified into any known genus and 44.3% (58/131) of the sequences show < 95% similarity to public database records, suggesting that abundant novel species exist in mariculture ponds. Gathering bacterial diversity data in mariculture ponds and diseased fish is meaningful for the prevention and control of fish diseases and for the improvement of our understanding of microbial ecology in a pond environment.NSFC [40632013, 40521003, 30900045]; MOST [200805068]; State Key Laboratory of Marine Environmental Science (Xiamen University) [MEL0701]; Natural Science Foundation of Guangdong Province, China [B09292