Distribution and influencing factors of acoustic characteristics of seafloor sediment in the Sunda Shelf

To understand the acoustic and physical properties of piston core samples collected from the Sunda continental shelf and analyze their distribution patterns,the samples were analyzed in laboratory,from which three provinces were divided in sound speed,sound speed ratio,porosity,wet bulk density,and maximum shear strength.ProvinceⅠhad lower sound speed and sound speed ratio(<1.04),high porosity,and low wet bulk density.ProvinceⅡhad higher sound speed and sound speed ratio(>1.04),low porosity,and high wet bulk density.ProvinceⅢhad the lowest sound speed and sound speed ratio(0.99),highest porosity(81%),and lowest wet bulk density(1.34 g/cm^(3)).The distribution pattern indicates that sediment movement,sediment source,topography,and hydrodynamic conditions influenced the distribution of acoustic and physical properties.Furthermore,we investigated the relationship of the maximum shear strength to the porosity and wet bulk density,and found that the maximum shear strength was proportional to both the porosity and wet bulk density.This finding has significant implications for ocean engineering applications.

Carbon Storage Dynamics in Lower Shimentan Formation of the Qiantang Sag, East China Sea Shelf Basin: Stratigraphy, Reservoir ‒ Cap Analysis, and Source ‒ Sink Compatibility

Excessive carbon emissions have resulted in the greenhouse effect, causing considerable global climate change. Marine carbon storage has emerged as a crucial approach to addressing climate change. The Qiantang Sag(QTS) in the East China Sea Shelf Basin, characterized by its extensive area, thick sedimentary strata, and optimal depth, presents distinct geological advantages for carbon dioxide(CO_(2)) storage. Focusing on the lower section of the Shimentan Formation in the Upper Cretaceous of the QTS, this study integrates seismic interpretation and drilling data with core and thin-section analysis. We reveal the vertical variation characteristics of the strata by providing a detailed stratigraphic description. We use petrophysical data to reveal the development characteristics of high-quality carbon-storage layers and favorable reservoircaprock combinations, thereby evaluating the geological conditions for CO_(2) storage in various stratigraphic sections. We identify Layer B of the lower Shimentan Formation as the most advantageous stratum for marine CO_(2) storage. Furthermore, we analyze the carbon emission trends in the adjacent Yangtze River Delta region. Considering the characteristics of the source and sink areas, we suggest a strong correlation between the carbon emission sources of the Yangtze River Delta and the CO_(2) storage area of the QTS, making the latter a priority area for conducting experiments on marine CO_(2) storage.

A case study of continental shelf waves in the northwestern South China Sea induced by winter storms in 2021

This study aims to investigate characteristics of continental shelf wave(CSW)on the northwestern continental shelf of the South China Sea(SCS)induced by winter storms in 2021.Mooring and cruise observations,tidal gauge data at stations Hong Kong,Zhapo and Qinglan and sea surface wind data from January 1 to February 28,2021 are used to examine the relationship between along-shelf wind and sea level fluctuation.Two events of CSWs driven by the along-shelf sea surface wind are detected from wavelet spectra of tidal gauge data.The signals are triply peaked at periods of 56 h,94 h and 180 h,propagating along the coast with phase speed ranging from 6.9 m/s to18.9 m/s.The dispersion relation shows their property of the Kelvin mode of CSW.We develop a simple method to estimate amplitude of sea surface fluctuation by along-shelf wind.The results are comparable with the observation data,suggesting it is effective.The mode 2 CSWs fits very well with the mooring current velocity data.The results from rare current help to understand wave-current interaction in the northwestern SCS.

Sedimentary systems of the Oligocene Huagang Formation in the central anticline zone of the Xihu Depression,East China Sea Shelf Basin

The Xihu Depression is the largest hydrocarbon-bearing depression of the East China Sea Shelf Basin(also referred to as the ECSSB).However,the depositional systems and reservoir distribution of the Oligocene Huagang Formation in the Xihu Depression are still controversial.Under the guidance of sedimentology and stratigraphy,this study documented a marine-terrestrial transitional environment in the restricted bay setting of the Oligocene Huagang Formation through core description,well logging,and seismic data analysis.This study also revealed that the Oligocene Huagang Formation is dominated by tidal delta,estuary,and gravity flow deposits in the central anticline zone of the Xihu Depression.The new understanding of the sedimentary systems and the discovery of the transgressive gap in the eastern Diaoyu Islands uplift explain the origin of fine-grained sediments and the EW-trending sand bodies in the central depression and the sand bodies parallel to shoreline in the west slope belt,which cannot be explained by previous study results,such as southern transgression or fluvial deltas and even lacustrine deposition.Moreover,the tidal channels,tidal sand flats,and gravity flow sand bodies formed by the transgressive tides are high-quality reservoirs.The study will provide a basis for well placement and serve as guidance for the selection of favorable hydrocarbon exploration areas in the Xihu Depression.

Comparative Transcriptomic Analysis of Two Tomato Cultivars with Different Shelf-Life Traits

Tomato(Solanum lycopersicum)is a perishable fruit because of its fast water loss and susceptibility to pathogens in the post-harvest stage,which leads to huge economic losses every year.In this study,firstly from 19 tomato cultivars,we screened out two cultivars,Riogrand and SalarF1,having long and short shelf-life spans,respectively.Secondly,shelf-life analysis was carried out for both cultivars at room temperature.Results exhibited that Riogrand showed higher firmness and less weight loss than SalarF1.The ethylene production was higher in SalarF1,compared with Riogrand during post-harvest storages.We performed transcriptomic analysis of both cultivars in different storage stages.We discovered 2913,2188,and 11,119 differentially expressed genes(DEGs)for three post-harvest stages(0,20,and 40 Days Post-Harvest(DPH)),respectively.These genes are enriched in ethylene biosynthesis and response,as well as cell wall-related genes.Ethylene response factor(ERF)ERF2 and ERF4 were highly expressed in SalarF1 with a short shelf life in 40 DPH,and the ethylene biosynthetic genes ACO1,ACO4,ACS6,and ACS2 were significantly upregulated in SalarF1.Regarding cell wall loosening and cell wall-related genes XTH3,XTH7,XTH23,1,3;1,4-β-D-Gluc-like,pGlcT1,Cellulase,PGH1,PL5,PL-like 1,PL-like 2 exhibited the highest levels of significance,being notably upregulated in the last stage of SalarF1.The quantitative real-time polymerase chain reaction(qRT-PCR)analysis validated these gene expressions,which is in line with the transcriptome analysis.The findings suggested that the extension of tomato fruit shelf life is mostly dependent on ethylene biosynthesis,signaling pathway genes,cell wall loosening,and cell wall-associated genes.

The variation in basal channels and basal melt rates of Pine Island Ice Shelf

In recent years,there has been a significant acceleration in the thinning,calving and retreat of the Pine Island Ice Shelf(PIIS).The basal channels,results of enhanced basal melting,have the potential to significantly impact the stability of the PIIS.In this study,we used a variety of remote sensing data,including Landsat,REMA DEM,ICESat-1 and ICESat-2 satellite altimetry observations,and Ice Bridge airborne measurements,to study the spatiotemporal changes in the basal channels from 2003 to 2020 and basal melt rate from 2010 to 2017 of the PIIS under the Eulerian framework.We found that the basal channels are highly developed in the PIIS,with a total length exceeding 450 km.Most of the basal channels are ocean-sourced or groundingline-sourced basal channels,caused by the rapid melting under the ice shelf or near the groundingline.A raised seabed prevented warm water intrusion into the eastern branch of the PIIS,resulting in a lower basal melt rate in that area.In contrast,a deepsea trough facilitates warm seawater into the mainstream and the western branch of the PIIS,resulting in a higher basal melt rate in the main-stream,and the surface elevation changes above the basal channels of the mainstream and western branch are more significant.The El Ni?o event in 2015–2016 possibly slowed down the basal melting of the PIIS by modulating wind field,surface sea temperature and depth seawater temperature.Ocean and atmospheric changes were driven by El Ni?o,which can further explain and confirm the changes in the basal melting of the PIIS.

Contributors to tidal duration asymmetry with varied coastline configurations on western shelf of Yellow Sea

Coastal management in China is confronted with an urgent choice between natural restoration and maintenance of existing seawalls and reclaimed land for economic development.A key criterion for making this decision is the resilience to coastal flooding,which depends on the ability to predict tidal level.Tidal duration asymmetry(TDA)is a key parameter in determination of the arrival and duration of flood tides.This study selected the western inner shelf of the Yellow Sea(WYS)as the study area and investigated the responses of TDA to different shoreline configurations and relative sea level rise.The responses of TDA to shoreline reconstruction yielded spatial variability locally and remotely.In the nearshore area,the responses of TDA to the complex ocean environment mainly originated from the combined functions of reflection,bottom friction,and advection,which controlled the energy transfer from M2 or S2 constituents to their overtides or compound tides.The sensitivity of TDA to coastline typologies was not limited to coastal waters but could stretch over the entire inner shelf.The vulnerability of tidal responses was due to the displacement of the M2 amphidrome of the Kelvin wave on the WYS,which in turn changed tidal energy fluxes over the regime.The relative sea level rise could intensify the feedback of TDA to seawalls and land reclamation.

Deep Learning-Based Classification of Rotten Fruits and Identification of Shelf Life

The freshness of fruits is considered to be one of the essential characteristics for consumers in determining their quality,flavor and nutritional value.The primary need for identifying rotten fruits is to ensure that only fresh and high-quality fruits are sold to consumers.The impact of rotten fruits can foster harmful bacteria,molds and other microorganisms that can cause food poisoning and other illnesses to the consumers.The overall purpose of the study is to classify rotten fruits,which can affect the taste,texture,and appearance of other fresh fruits,thereby reducing their shelf life.The agriculture and food industries are increasingly adopting computer vision technology to detect rotten fruits and forecast their shelf life.Hence,this research work mainly focuses on the Convolutional Neural Network’s(CNN)deep learning model,which helps in the classification of rotten fruits.The proposed methodology involves real-time analysis of a dataset of various types of fruits,including apples,bananas,oranges,papayas and guavas.Similarly,machine learningmodels such as GaussianNaïve Bayes(GNB)and random forest are used to predict the fruit’s shelf life.The results obtained from the various pre-trained models for rotten fruit detection are analysed based on an accuracy score to determine the best model.In comparison to other pre-trained models,the visual geometry group16(VGG16)obtained a higher accuracy score of 95%.Likewise,the random forest model delivers a better accuracy score of 88% when compared with GNB in forecasting the fruit’s shelf life.By developing an accurate classification model,only fresh and safe fruits reach consumers,reducing the risks associated with contaminated produce.Thereby,the proposed approach will have a significant impact on the food industry for efficient fruit distribution and also benefit customers to purchase fresh fruits.

Exogenous melatonin improves the chilling tolerance and preharvest fruit shelf life in eggplant by affecting ROS-and senescence-related processes

Low temperature is the most common abiotic stress factors during the eggplant cultivation in solar greenhouses.Melatonin plays important roles in plant resistance to low temperature.However,the role of melatonin in regulating chilling tolerance and extending the preharvest shelf life of eggplant fruits is still unknown.In this study,we investigated the effects of exogenous melatonin on eggplant plants and fruits in response to low temperature.Under simulated low-temperature conditions,exogenous melatonin significantly relieved the chilling symptoms of seedlings by reducing reactive oxygen species (ROS) and malondialdehyde (MDA) levels and relative leakage rates.These reductions were caused by higher superoxide dismutase (SOD) and catalase (CAT) activities and increased endogenous polyamine and melatonin levels compared with those in untreated seedlings.Notably,the expression levels of SOD,CAT1/2,and polyamine synthesis genes (ADC and ODC) were also increased by 100μmol·L~(-1)melatonin,as well as those of genes involved in melatonin synthesis (TDC,T5H,SNAT,ASMT,and COMT) and cold regulation (COR1,CBFa/b,and ZAT2/6/12).To further investigate the effects of melatonin on eggplant leaves and fruits under natural low temperature conditions,100μmol·L~(-1)melatonin was sprayed on the functional leaves at three days before commodity maturation.Melatonin significantly alleviated chilling injury in the leaves and pericarp and extended the preharvest shelf life of the fruit by increasing the expression of COR1,CBF,ZAT2/6/12,and API5 and decreasing the expression of senescence-related genes (NCED1/2 and SAG12).Therefore,100μmol·L~(-1)melatonin improved chilling tolerance and fruit shelf life by upregulating ZAT2/6/12 to affect ROS-and senescence-related processes,which provides a reference for alleviating cold stress and extending the preharvest fruit shelf life in eggplant.

New interpretation on the provenance changes of the upper Pinghu–lower Huagang Formation within Xihu Depression,East China Sea Shelf Basin

Both Pinghu and Huagang formations are important hydrocarbon reservoirs of the Xihu Depression in the East China Sea Shelf Basin.Clarifying the source suppliers and restoring source-to-sink transport routes are of great significance to the future petroleum and gas undertakings.Previous researchers were largely confined by either limitation of geological records,highly dependence on a singular method or low-precision dating techniques.Our study integrated heavy mineral assemblages,geochemical analyses and detrital zircon U-Pb dating to reconstruct multiple source-to-sink pathways,and to provide a better understanding on the provenance evolution for the upper Pinghu–lower Huagang depositions of the Xihu Depression.At least three major provenances have been confirmed and systematically investigated for their separate compositional features.The Hupijiao Uplift(or even farther northern area)was dominated by a major Paleoproterozoic population peaked at ca.1830 Ma along with minor Mesozoic clusters.The Haijiao Uplift to the west and the Yushan Low Uplift to the southwest,on the other hand,generate opposite U-Pb age spectra with apparently larger peaks of Indosinian and Yanshanian-aged zircons.To be noted,both Indosinian and Paleoproterozoic peaks are almost identical in proportion for the Haijiao Uplift.The overall sedimentary pattern of late Eocene-early Oligocene was featured by both spatial and temporal distinction.The Hupijiao Uplift was likely to cast limited impact during the late Eocene,whereas the broad southern Xihu Depression was transported by a large abundance of materials from the nearby Haijiao and Yushan Low Uplifts.The northern source substantially extended its influence to the farther south during the early Oligocene by delivering plentiful sediments of higher-degree metamorphic parent rocks.Combined with the proximal western and southwestern suppliers,the overall Xihu Depression was under control from both distant and local provenances.

Application of seismic sedimentology in characterization of fluvial-deltaic reservoirs in Xihu sag, East China Sea shelf basin

The fluvial-deltaic reservoirs of the Oligocene Huagang Formation in the Xihu sag of the East China Sea shelf basin reflect rapid lateral change in sedimentary facies and poor morphology of conventional slice attributes,which bring difficulties to the reservoir prediction for subsequent exploration and development of lithologic reservoirs.The traditional seismic sedimentology technology is optimized by applying the characteristic technologies such as frequency-boosting interpretation,inversion-conventional–90°phase shift joint construction of seismic lithologic bodies,nonlinear slices,paleogeomorphology restoration,and multi-attribute fusion,to obtain typical slice attributes,which are conducive to geological form description and sedimentary interpretation.The Huagang Formation developed three types of sedimentary bodies:braided river,meandering river and shallow water delta,and the vertical sedimentary evolution was controlled by the mid-term base-level cycle and paleogeomorphology.In the early–middle stage of the mid-term base-level ascending cycle,braided channel deposits were dominant,and vertical superimposed sand bodies were developed.In the late stage of the ascending half-cycle and the early stage of the descending half-cycle,meandering river deposits were dominant,and isolated sand bodies were developed.In the middle–late stage of the descending half-cycle,shallow-water delta deposits were dominant,and migratory medium–thick sand bodies were developed.Restricted paleogeomorphology controlled the sand body distribution,while non-restricted paleogeomorphology had little effect on the sand body distribution.Based on reservoir characterization,the fault sealing type and reservoir updip pinch-out type structural lithological traps are proposed as the main directions for future exploration and development in the Xihu sag.

The Processes-Based Attributes of Four Major Surface Melting Events over the Antarctic Ross Ice Shelf

The Ross-Amundsen sector is experiencing an accelerating warming trend and a more intensive advective influx of marine air streams.As a result,massive surface melting events of the ice shelf are occurring more frequently,which puts the West Antarctica Ice Sheet at greater risk of degradation.This study shows the connection between surface melting and the prominent intrusion of warm and humid air flows from lower latitudes.By applying the Climate Feedback-Response Analysis Method(CFRAM),the temporal surge of the downward longwave(LW)fluxes over the surface of the Ross Ice Shelf(RIS)and adjacent regions are identified for four historically massive RIS surface melting events.The melting events are decomposed to identify which physical mechanisms are the main contributors.We found that intrusions of warm and humid airflow from lower latitudes are conducive to warm air temperature and water vapor anomalies,as well as cloud development.These changes exert a combined impact on the abnormal enhancement of the downward LW surface radiative fluxes,significantly contributing to surface warming and the resultant massive melting of ice.

Predicting impacts of climate change on the biogeographic patterns of representative species richness in Prydz Bay-Amery Ice Shelf

The research on the biological ecology of the Prydz Bay-Amery Ice Shelf in East Antarctica is inadequate under the increasing threat from climate change,especially for Antarctic fish and krill.The Dynamic Bioclimatic Envelope Model(DBEM)has been widely used in predicting the variation of species distribution and abundance in ocean and land under climate change;it can quantify the spatiotemporal changes of multi population under different climate emission scenarios by identifying the environmental preferences of species.The species richness and geographical pattern of six Antarctic representative species around Prydz Bay-Amery ice shelf were studied under RCP 8.5 and RCP 2.6 emission scenarios from 1970 to 2060 using Geophysical Fluid Dynamics Laboratory(GFDL),Institut Pierre Simon Laplace(IPSL),and Max Planck Institute(MPI)earth system models.The results showed that the species richness decreased as a whole,and the latitude gradient moved to the pole.The reason is that ocean warming,sea ice melting,and human activities accelerate the distribution changes of species biogeographical pattern,and the habitat range of krill,silverfish,and other organisms is gradually limited,which further leads to the change of species composition and the decrease of biomass.It is obvious that priority should be given to Prydz Bay-Amery ice shelf in the planning of Marine Protected Areas(MPAs)in East Antarctica.

Clay minerals and elemental composition of sediments on different sedimentary units in the northern East China Sea shelf:provenance tracing and genetic mechanism analysis

The composition,provenance,and genetic mechanism of sediment on different sedimentary units of the East China Sea(ECS)shelf are essential for understanding the depositional dynamics environment in the ECS.The sediments in the northern ECS shelf are distributed in a ring-shaped distribution centered on the southwestern Cheju Island Mud.From the inside to the outside,the grain size goes from fine to coarse.Aside from the“grain size effect”,hydrodynamic sorting and mineral composition are important restrictions on the content of rare earth elements(REEs).Based on the grain size,REEs,and clay mineral composition of 300 surface sediments,as well as the sedimentary genesis,the northern ECS shelf is divided into three geochemical zones:southwestern Cheju Island Mud Area(ZoneⅠ),Changjiang Shoal Sand Ridges(ZoneⅡ-1),Sand Ridges of the East China Sea shelf(ZoneⅡ-2).The northern ECS shelf is mostly impacted by Chinese mainland rivers(the Changjiang River and Huanghe River),and the provenance and transport mechanism of sediments of different grain sizes is diverse.The bulk sediments come primarily from the Changjiang River,with some material from the Huanghe River carried by the Yellow Sea Coastal Current and the North Jiangsu Coastal Current,and less from Korean rivers.Among them,surface sediments in the southwestern Cheju Island Mud Area(ZoneⅠ)come mostly from the Changjiang River and partly from the Huanghe River.It was formed by the counterclockwise rotating cold eddies in the northern ECS shelf,which caused the sedimentation and accumulation of the fine-grained sediments of the Changjiang River and the Huanghe River.The Changjiang Shoal Sand Ridges(ZoneⅡ-1)were developed during the early-middle Holocene sea-level highstand.It is the modern tidal sand ridge sediment formed by intense hydrodynamic action under the influence of the Yellow Sea Coastal Current,North Jiangsu Coastal Current,and Changjiang Diluted Water.The surface sediments mainly originate from the Changjiang River and Huanghe River,with the Changjiang River dominating,and the Korean River(Hanjiang River)influencing just a few stations.Sand Ridges of the East China Sea shelf(ZoneⅡ-2)are the relict sediments of the paleo-Changjiang River created by sea invasion at the end of the Last Deglaciation in the Epipleistocene.The clay mineral composition of the surface sediments in the study area is just dominated by the Changjiang River,with the North Jiangsu Coastal Current and the Changjiang Diluted Water as the main transporting currents.

The morphological changes of basal channels based on multisource remote sensing data at the Pine Island Ice Shelf

The basal channel is a detailed morphological feature of the ice shelf caused by uneven basal melting.This kind of specifically morphology is widely distributed in polar ice shelves.It is an important research object of sea-ice interaction and plays a vital role in studying the relationship between the ice sheet/ice shelf and global warming.In this paper,high-resolution remote sensing image and ice penetration data were combined to extract the basal channel of the Pine Island Ice Shelf.The depth variation of Pine Island Ice Shelf in the recent 20 years was analyzed and discussed by using ICESat-1,ICESat-2,and IceBridge data.Combined with relevant marine meteorological elements(sea surface temperature,surface melting days,circumpolar deep water and wind)to analyze the basal channel changes,the redistribution of ocean heat is considered to be the most important factor affecting the evolution and development of the basal channel.

Origin of hydrocarbon fluids and discussion of abnormal carbon isotopic compositions in the Lishui-Jiaojiang Sag,East China Sea Shelf Basin

The hydrocarbon gases in the L1 gas field of the Lishui-Jiaojiang Sag have been commonly interpreted to be an accumulation of pure sapropelic-type thermogenic gas.In this study,chemical components,stable isotopic compositions,and light hydrocarbons were utilized to shed light on the origins of the hydrocarbon fluids in the L1gas pool.The hydrocarbon fluids in the L1 gas pool are proposed to be a mixture of three unique components:mid-maturity oil from the middle Paleocene coastal marine Lingfeng source rock,oil-associated(late oil window)gas generated from the lower Paleocene lacustrine Yueguifeng source rock,and primary microbial gas from the paralic deposits of the upper Paleocene Mingyuefeng source rock.Here,for the first time,the hydrocarbon gases in the L1 gas pool are diagnosed as mixed oil-associated sapropelic-type gas and microbial gas via four pieces of principal evidence:(1)The abnormal carbon isotopic distributions of all methane homologues from C_(1)(CH_(4)or methane)to C_(5)(C_(5)H_(12)or pentane)shown in the Chung plot;(2)the diagnostic~(13)C-depleted C_(1)compared with the thermogenic sapropelic-type gas model,whileδ^(13)C_(2)(C_(2)H_(6)or ethane)andδ^(13)C_(3)(C_(3)H_(8)or propane)both fit perfectly;(3)the excellent agreement of the calculated carbon isotopic compositions of the pure thermogenic gas with the results of the thermal simulated gas from the type-II1 kerogen-rich Yueguifeng source rock;and(4)the oil-associated gas inferred from various binary genetic diagrams with an abnormally elevated gas oil ratio.Overall,the natural gases of the L1 gas pool were quantified in this study to comprise approximately 13%microbial gas,nearly 48%oil-associated sapropelic-type gas,and 39%of nonhydrocarbon gas.The microbial gas is interpreted to have been codeposited and entrained in the humic-kerogen-rich Mingyuefeng Formation under favorable lowtemperature conditions during the late Paleocene-middle Eocene.The microbial gas subsequently leaked into the structurally and stratigraphically complex L1 trap with oil-associated sapropelic-type gas from the Yueguifeng source rock during the late Eocene-Oligocene uplifting event.A small amount of humic-kerogen-generated oil in the L1 gas pool is most likely to be derived from the underlying Lingfeng source rock.The detailed geological and geochemical considerations of source rocks are discussed to explain the accumulation history of hydrocarbon fluids in the L1 gas pool.This paper,therefore,represents an effort to increase the awareness of the pitfalls of various genetic diagrams,and an integrated geochemical and geological approach is required for hydrocarbonsource correlation.

Mesozooplankton distribution and diversity from the Bering Sea shelf to the Chukchi Sea

In recent decades,environmental changes in the Arctic have aroused widespread concern around the world.To better understand ecology issues such as ecosystem dynamics,the Arctic and the subarctic regions were integrated as the“pan-Arctic”region.In this study,mesozooplankton were sampled from the Bering Sea shelf to the northern Chukchi Sea during the 10th Chinese National Arctic Research Expedition in 2019.Based on the species composition and abundance,three geographical communities were identified:the Bering Sea shelf community(BSS),the Bering Strait transitional community(BST),and the Chukchi Sea shelf community(CSS).The BSS was characterized by Bering Sea oceanic species such as Eucalanus bungii;the BST was mainly composed of the pan-Arctic distributed Calanus glacialis,meroplankton of benthos,and neritic species such as Centropages abdominalis;copepods,especially the copepodite of C.glacialis,were predominant in the CSS community.The BSS community structure was strongly affected by the inflow of Bering Shelf Water,while those of BST and CSS were determined by the recruitment of local species.The zooplankton community structure is influenced by both advection and environmental changes such as warming and a prolonged productivity period.Here,it was difficult to distinguish the changes induced by climate change from the effects of the Bering Sea Water.The key to solving this problem is the accumulation of comparable data,which requires continuous monitoring of key species such as C.glacialis and Calanus hyperboreus.

采前氯化钙和水杨酸处理对蟠枣采后贮藏品质的影响

为探究采前处理对蟠枣果实采后贮藏品质的影响,以新疆主栽鲜食品种蟠枣为研究对象,分别于果实花期、幼果期、膨大期、着色期采用清水(CK)、10 g/L氯化钙(CaCl_(2))、100 mmol/L水杨酸(SA)和10 g/L CaCl_(2)+100 mmol/L SA进行采前喷施处理,采收后置于常温货架贮藏,每天统计果实的转红率、转红指数、腐烂率和失重率,测定果实的可溶性固形物含量、硬度和色泽等指标。结果表明:采前喷施CaCl_(2)、SA和CaCl_(2)+SA均可一定程度上抑制蟠枣的转红和腐烂,使其保持较低的失重率,使果实维持较高的可溶性固形物含量和硬度,保持较好的色泽,其中,10 g/L CaCl_(2)+100 mmol/L SA采前处理效果最佳,常温货架8 d时,果实的转红率和腐烂率分别较对照低23.34个百分点和36.66个百分点,失重率仅为1.68%,果实可溶性固形物含量维持在21.47%,硬度为9.45 kg/cm^(2),保持较好的商品性。综上,采前喷施10 g/L CaCl_(2)+100 mmol/L SA能有效保持蟠枣采后贮藏品质。

新型包装材料对甜玉米贮藏品质的影响

甜玉米采后代谢旺盛,品质极易发生劣变,包装保鲜为最简单的解决方式。为明确包装材料对甜玉米贮藏品质的影响,以“BM380”甜玉米为试验材料,研究采用7种材料包装的甜玉米在2~5℃贮藏条件下的失重率、感官品质、可溶性糖含量和VC含量的变化,并以感官品质为最主要指标判断包装材料的保鲜效果。结果表明:在7种包装材料中,欧乐甜玉米保鲜袋在降低甜玉米失重率方面表现最优,在贮藏14 d时失重率仅0.746%;生物气调保鲜包装袋包装的甜玉米在超市冷链销售保鲜期最长,可达7d,比对照超市聚乙烯包装袋延长4d,贮藏16d时感官指数为3.01,仍具食用价值,其次是欧乐甜玉米保鲜袋包装,甜玉米超市冷链销售保鲜期为6 d,贮藏13 d时感官指数为4.33,仍具食用价值;复命锁鲜袋可以维持甜玉米的VC含量,贮藏12d的VC含量较对照显著提高46.8%,其次是欧乐甜玉米保鲜袋包装,贮藏12、15d分别较对照显著提高38.03%、11.32%;加厚(抗菌/保鲜)膜自制包装袋包装的甜玉米可溶性糖含量下降最缓慢,贮藏15 d的可溶性糖含量比对照显著提高73.11%,欧乐甜玉米保鲜袋包装较对照显著提高49.09%。可见,欧乐甜玉米保鲜袋可减缓甜玉米失重,生物气调保鲜包装袋的冷链保鲜期较长,复命锁鲜袋可维持甜玉米的VC含量,加厚(抗菌/保鲜)膜自制包装袋可保持甜玉米的可溶性糖含量。综合考虑失重率、感官指数及营养成分损失情况,建议选择欧乐甜玉米保鲜袋。

超高压处理对鲜榨复配果汁品质及货架期的影响

为使经杀菌处理后果汁的活性成分和风味物质更接近原鲜榨果汁,本研究以猕猴桃、菠萝、芒果为原料制备复配果汁,对比超高压处理与热处理(85℃、5 min)两种杀菌方式对鲜榨复配果汁品质及货架期的影响。结果表明:复配果汁比例V菠萝原浆:V猕猴桃原浆:V芒果原浆=4:2:4时,与传统热处理相比,在450 MPa、25℃、15 min超高压条件下处理,pH、b^(*)值、可溶性固形物无明显差异(P>0.05),维生素C含量损失减少12.1%、多酚含量损失减少17.5%,品质更接近于未处理果汁;通过对复配果汁主要挥发性成分进行分析,烯类、酯类、醇类、酮类、醛类等风味物质的损失显著小于(P<0.05)热处理,且蒸煮味物质糠醛没有生成,丙酮和1-辛烯-3-酮相对含量分别减少68.4%、41.4%;菌落总数、霉菌和酵母菌杀菌效果均符合饮料现行有效卫生标准;通过Q_(10)模型对货架期进行预测,在4℃条件下储藏,其货架期可达到103 d。综上,超高压处理鲜榨复配果汁在有效杀灭微生物的同时更利于复配果汁保持天然品质及其货架期。