Short Comments on the Application of Criteria for Identifying Ecologically or Biologically Significant Marine Areas (EBSAs)

In 2008, the Convention on Biological Diversity adopted seven criteria for identifying ecologically or biologically significant marine areas (EBSAs) for biodiversity conservation. Nine international workshops were held in which 209 areas and 38 potential areas were identified as meeting the EBSA criteria. This study analyzes the 209 identified areas and reveals that the use of the seven criteria in different workshops differed, so their scores are therefore not quantifiable. Furthermore, descriptions specific to criteria regarding areas having “special importance for the life-history stages of species” accounted for only 1.44% of the overall descriptions. Most descriptions regarding “vulnerability, fragility, sensitivity, or slow recovery” were almost contributed by the “importance of threatened, endangered, or declining species and/or habitats”. These three criteria were based on scientific evidences and have been widely accepted by the public. Therefore, we would suggest the criteria of “special importance for the life-history stages of species” and the criteria of “vulnerability, fragility, sensitivity, or slow recovery” need further investigation for biodiversity conservation

Simulation Experiment of Environmental Impact of Deep-Sea Mining: Response of Phytoplankton Community to Polymetallic Nodules and Sediment Enrichment in Surface Water

In this paper, simulation experiments were conducted to study the response of phytoplankton biomass and community composition to the influence of polymetallic nodules and sediment at four stations in the western Pacific in 2021. Chlorophyll a, pico-phytoplankton cell abundance, and metal concentration were measured before and after 24 h of deck incubation. The results show that there were three different patterns of response, namely, restrained, stimulated, and unaffected patterns. The restrained pattern appeared in the filtered treatments at station Incub.01, and the stimulated pattern appeared in the unfiltered treatments at station Incub.02. The response of the phytoplankton was not detectable at stations Incub.03 and 04. Regardless, positive and negative responses were found in the dominant pico-phytoplankton group—Prochlorococcus—and with slight variation in Synechococcus. The concentration of manganese varied among the treatments compared to that of iron and other metals. The factors affecting the growth of the phytoplankton in this study were metal concentrations and turbidity. The phytoplankton biomass baseline may also have played an important role: the lower the biomass, the higher the growth rate. This study proved that deep-sea polymetallic nodule mining will have a specific impact on surface phytoplankton biomass, but turbidity and particle retention time could be important factors in mitigating the extent of the impact

A Comprehensive Analysis of the <i>Fowleria variegata</i> (Valenciennes, 1832) Mitochondrial Genome and Its Phylogenetic Implications within the Family Apogonidae

Controversies surrounding the phylogenetic relationships within the family Apogonidae have persisted due to the limited molecular data, obscuring the evolution of these diverse tropical marine fishes. This study presents the first complete mitochondrial genome of Fowleria variegata, a previously unrepresented genus, using high-throughput Illumina sequencing. Through a comparative mitogenomic analysis, F. variegate was shown to exhibit a typical genome architecture and composition, including 13 protein-coding, 22 tRNA and 2 rRNA genes and a control region, consistent with studies of other Apogonidae species. Nearly all protein-coding genes started with ATG, while stop codons TAA/TAG/T were observed, along with evidence of strong functional constraints imposed via purifying selection. Phylogenetic reconstruction based on maximum likelihood and Bayesian approaches provided robust evidence that F. variegata forms a basal lineage closely related to P. trimaculatus within Apogonidae, offering novel perspectives into the molecular evolution of this family. By generating new mitogenomic resources and evolutionary insights, this study makes important headway in elucidating the phylogenetic relationships and mitogenomic characteristics of Apogonidae fishes. The findings provide critical groundwork for future investigations into the drivers of diversification, speciation patterns, and adaptive radiation underlying the extensive ecological diversity and biological success of these marine fishes using phylogenomics and population genomics approaches

Increased nitrous oxide emissions from intertidal soil receiving wastewater from dredging shrimp pond sediments

The quantities of greenhouse gas emissions and the activity of functional microbes in coastal soils receiving nutrient-rich wastewaters from mariculture activities have seldom been reported. We investigated the effects of wastewater discharge resulting from dredging shrimp pond sediment on the soil fluxes of methane (CH _4 ) and nitrous oxide (N _2 O) in intertidal areas and on the functional microorganisms and physio-chemical characteristics of soil. The temporal variations in gas fluxes and soil characteristics following wastewater discharge were also evaluated with the tidal regime on the day of discharge taken into account. The results showed that wastewater discharge immediately resulted in higher levels of ammonia (NH _4 ^+ -N) deposited and N _2 O emissions from the soil at the discharge site than at the non-discharge site, while the CH _4 flux was not affected. The increase in N _2 O flux lasted for a longer time when the discharge was performed during a neap tide day than when it was performed during a spring tide day. Wastewater discharge also increased the abundance of ammonia-oxidizing bacterial (AOB) amoA genes and nosZ genes in soil rather than increasing the abundance of narG and nirK genes. The pattern of temporal variations between the N _2 O flux and soil NH _4 ^+ –N content was similar to that between the flux and the AOB- amoA gene abundance, suggesting that bacterial nitrification was important for N _2 O production in soil receiving the dredging wastewater. The results suggest that the wastewater discharge impacts nitrogen metabolism processes and causes a significant N _2 O emission problem; therefore, pollutant management is essential in shrimp culturing activities to reduce greenhouse gas emissions into the atmosphere

Decline of Microcystis aeruginosa FACHB-905 under four stress conditions

The present study aimed to evaluate the contribution of stress factors to the decline of Microcystis bloom, also tried to develop some indicator of decline. Four stress conditions including nitrogen starvation, phophorus starvation, dark and low temperature (10 degrees C) were designed, Decrease of biomass and the concomitant change of antioxidant system, including superoxide dismutase (SOD) and catalase (CAT) activities were detected. The result indicated that growth was significantly inhibited under dark and low temperature. Microcystis population declined after 25 days tinder dark, while declined after only 7 days under low temperature. Compared with the physical stress, nutrition such as nitrogen and phosphorus did not limit the growth effectively in the early stage. Chlorophyll-a decreased as soon as being incubated into nitrogen free BG-11 medium. After being kept in phosphorus free medium for 20 days. chlorophyll-a reached peak, about the twice of the initial concentration, and then decreased at a rate of 0.1 mg/(L.d), which was the highest decaying rate among the four factors. It indicated its significance of available phosphorus for Microcystis survival and decline. According to the results, when phosphorus was limited, or water temperature was decreased to 10 degrees C, cautions should be taken into account for the decrease of dissolved oxygen and possible increase of toxins or odors substances from the declining bloom, In healthy Microcystis, SOD activity was about 0.06U/mg protein, while CAT activity was too low to be measured. In addition, SOD activity increased earlier than CAT activity when Microcystis was exposed to stress conditions. CAT activity increased only when the content of chlorophyll-a began to decline. Both of the increase of SOD and CAT activities correlated negatively with the decrease of the content of chlorophyll-a though there were some exceptions. Combination of the two parameters would be potential indicator of bloom decline

Applicability of the fluorescein diacetate assay for metabolic activity measurement of Microcystis aeruginosa (Chroococcales, Cyanobacteria)

The fluorescein diacetate (FDA) assay has been widely used to measure metabolic activity in phytoplankton. It was found that FDA fluorescence values did not decrease in some stressed cells, demonstrating that the applicability of the method needs to be assessed further in the context of growth-influencing conditions. In the present study, changes of FDA fluorescence values were studied in bloom-forming cyanobacterial Microcystis aeruginosa Kutz cells under stress conditions such as nitrogen (N) or phosphorus (P) deficiency, or darkness and low temperature (10 degrees C), respectively. The results demonstrated that esterase activity decreased immediately in dark-stressed cells, which correlated with the decline of biomass and photosynthetic activity. Under the other three stress conditions, however, especially at low temperature, the cells lost photosynthetic activity but had the highest esterase activity, which was five times higher than the control group. These findings contrast with the assay criteria that the expression of a stain should reflect the change of photosynthetic activity and that stressed cells should have a lower staining intensity than the control cells. According to these results, the esterase activity response was dependent on environmental factors. Furthermore, higher fluorescence intensity did not mean higher metabolic activity, but a discrepant value indicated a severe stress

Prospective observational cohort study on grading the severity of postoperative complications in global surgery research

Background The Clavien–Dindo classification is perhaps the most widely used approach for reporting postoperative complications in clinical trials. This system classifies complication severity by the treatment provided. However, it is unclear whether the Clavien–Dindo system can be used internationally in studies across differing healthcare systems in high- (HICs) and low- and middle-income countries (LMICs). Methods This was a secondary analysis of the International Surgical Outcomes Study (ISOS), a prospective observational cohort study of elective surgery in adults. Data collection occurred over a 7-day period. Severity of complications was graded using Clavien–Dindo and the simpler ISOS grading (mild, moderate or severe, based on guided investigator judgement). Severity grading was compared using the intraclass correlation coefficient (ICC). Data are presented as frequencies and ICC values (with 95 per cent c.i.). The analysis was stratified by income status of the country, comparing HICs with LMICs. Results A total of 44 814 patients were recruited from 474 hospitals in 27 countries (19 HICs and 8 LMICs). Some 7508 patients (16·8 per cent) experienced at least one postoperative complication, equivalent to 11 664 complications in total. Using the ISOS classification, 5504 of 11 664 complications (47·2 per cent) were graded as mild, 4244 (36·4 per cent) as moderate and 1916 (16·4 per cent) as severe. Using Clavien–Dindo, 6781 of 11 664 complications (58·1 per cent) were graded as I or II, 1740 (14·9 per cent) as III, 2408 (20·6 per cent) as IV and 735 (6·3 per cent) as V. Agreement between classification systems was poor overall (ICC 0·41, 95 per cent c.i. 0·20 to 0·55), and in LMICs (ICC 0·23, 0·05 to 0·38) and HICs (ICC 0·46, 0·25 to 0·59). Conclusion Caution is recommended when using a treatment approach to grade complications in global surgery studies, as this may introduce bias unintentionally

Critical care admission following elective surgery was not associated with survival benefit: prospective analysis of data from 27 countries

This was an investigator initiated study funded by Nestle Health Sciences through an unrestricted research grant, and by a National Institute for Health Research (UK) Professorship held by RP. The study was sponsored by Queen Mary University of London