The aim of this study was to investigate the effect of storage conditions on the sensory quality, colour and texture of fresh-cut cabbage during the addition of ascorbic acid, citric acid and calcium chloride. Ascorbi...The aim of this study was to investigate the effect of storage conditions on the sensory quality, colour and texture of fresh-cut cabbage during the addition of ascorbic acid, citric acid and calcium chloride. Ascorbic acid maintained the overall quality for 14 days at 0℃ and 7 days at 5℃;no difference, however, was observed regarding browning of cut surface compared to the control sample at both storage temperatures. Calcium chloride maintained the overall quality and cut surface browning for 14 days at both storage temperatures. It was also found that citric acid 1% can be used for minimally processed cabbage. Soaking with citric acid helped retain the color and increased the overall acceptance and organoleptic quality of fresh cut cabbage;it reduced browning of the cut surface and protected against formation of black specks. Citric acid treatment combined with low temperature storage (0℃) prolonged the shelf life of minimally processed cabbage for 22 days, time sufficient for acceptable marketing of the product. The lightness of minimally processed cabbage decreased linearly from 70.94 ± 6 to 63.8 ± 8.5 - 61.3 ± 8 units for the chemical treatments during 22 days of storage at 0℃. Hue angle values during storage time were also significantly influenced by chemical treatments mainly at 0℃.展开更多
[Objectives]This study was conducted to investigate the effect of compound fresh-keeping liquid on the browning and quality of fresh-cut yam during the cold chain process.[Methods]Under the simulated cold chain condit...[Objectives]This study was conducted to investigate the effect of compound fresh-keeping liquid on the browning and quality of fresh-cut yam during the cold chain process.[Methods]Under the simulated cold chain condition of 4℃,a uniform design(U6*(64))experiment was carried out to optimize the compound preservative formula,and a better compound preservative formula was obtained using the regression equation.[Results]The compound preservative formula was:AA 0.25%,CA 0.5%,Nisin 0.09%,GSH 0.15%.The compound fresh-keeping liquid effectively delayed the browning of fresh-cut yam and the accumulation of MDA,maintained the content of TSS,inhibited the activity of PAL and delayed the appearance of the maximum activity of POD and POD.[Conclusions]This study provides technical support for the actual extension of the shelf life of fresh-cut yam.展开更多
Over the last several decades,the Mediterranean region has been subjected to mountain abandonment and farming cessation,leading to changes in vegetation and coenological features of grasslands,contextually to the stro...Over the last several decades,the Mediterranean region has been subjected to mountain abandonment and farming cessation,leading to changes in vegetation and coenological features of grasslands,contextually to the strong decline of the rock partridge(Alectoris graeca).Our hypothesis was that the ongoing dynamic processes leading to the compositional changes of grasslands in central Apennines affect the habitat suitability for the singing male(territorial male defending its reproductive site).In 2015,we defined the presence/absence of spring territorial singing males in seven sites(1,250-2,400 m a.s.l.),by the census in 74 playback stations,distributed along 15 transects.We characterized the topography and the vegetation mosaic of such sites according to the collected topographic and vegetation cover data in 59 randomly selected plots(100 m×100 m)along the transects.To understand the relations among the environmental variables and the effect of the composition and dynamism of the vegetation mosaics on the presence/absence of the singing male,we used principal components analysis and generalized linear mixed-effect modelling.Our results emphasized the marked overlap between the general environmental conditions,which proved to define the habitat suitability for A.graeca,and the characteristics of the site chosen by the singing male for starting the reproductive activities.Moreover,we found that the site suitability for the singing male decreases when the vegetation recovery processes are ongoing,because of the spread of coarse tall grassesdominated communities and/or grassland types with dense turf.Tall grass-dominated communities and thick-turf grasslands exert their negative effect decreasing the habitat suitability for the singing male starting from low cover values.Therefore,it is conceivable that singing male’s suitable habitat will be dramatically restricted to the steepest south-facing slopes,where topographic and soil conditions do not allow the spread of grasslands with dense turf and of invasive/dominant tall grasses,increasing the threat to the species due to the effect of climate change on the vegetation features.展开更多
The problem of habitat fragmentation is recently an important issue in ecological research as well as in the practical approach of nature conservation. According to the most popular approaches, habitats are considered...The problem of habitat fragmentation is recently an important issue in ecological research as well as in the practical approach of nature conservation. According to the most popular approaches, habitats are considered as the homogenous parts of the landscape. Also the metapopulation concept problem of the inert habitat heterogenity is considered quite seldom. These approaches have some weak points resulting from the assumption that the border between habitat patches and the metapopulation matrix is fairly sharp. This paper presents a resource-based concept of habitats, based on mathematical theory of point processes, which can be easily applied to analysing the problem of uneven distribution of resources. The basic assumption is that the random distribution of resources may be mathematically described as the realisation of a certain point process. According to our method, it is possible to calculate the expected quantities of available resources as well as the minimum area of habitat that includes the expected abundance of the resource. This approach may be very useful to understand some crucial phenomena in landscape ecology, such as the patch size effect and its connection to habitat loss and fragmentation.展开更多
Background The provision of habitat for fishery species in estuaries is highly valued and represents one of the most challenging ecosystem service values to quantify.However,quantifying this value is challenging due t...Background The provision of habitat for fishery species in estuaries is highly valued and represents one of the most challenging ecosystem service values to quantify.However,quantifying this value is challenging due to complex relationships between habitat change,ecological processes,and environmental variations.This study aims to estimate estuarine habitat degradation and its impact on the reproduction process of the crab Eriocheir sinensis by characterizing the changes in breeding habitat and investigating relationships between the species and its habitat in the Yang-tze River Estuary.Methods A species distribution model recently developed was applied to estimate the extent and quality of breeding habitat changes from 2014-2021.The intrinsic(physiological)and external(structural)reproductive attributes of the breeding process were measured to assess the effects of habitat change.The relationships among habitat change,reproductive attributes and environmental factors were analyzed to understand the underlying driving forces of habitat degradation for breeding process by multivariate statistical analysis.Results About 34.24%of essential habitat was lost,mainly in highly suitable areas due to reclamation and waterway construction.Habitat degradation significantly affects female distribution and their reproductive processes,particularly gonad development during the pre-reproductive period and fecundity during the reproductive period,without altering population structure.These results indicated that the main ecological function served by the highly suitable breeding ground was the provision for development of gonad and improvement of fecundity.Increases of salinity and turbidity,caused by hydrodynamic changes from large-scale waterway construction,were identified as the environmental determinants contributing to cumulative habitat degradation.These influences ultimately led to a decrease in the fecundity of E.sinensis.Conclusions Our research sheds light on the quantification of habitat degradation in the Yangtze River Estuary and its implications for the reproduction process of E.sinensis,which can serve as a foundation for assessing and quantifying the ecosystem service values provided by these breeding grounds.This information is valuable for policymakers and resource managers in making informed decisions regarding habitat conservation and the sustainable utilization of fishery resources.展开更多
文摘The aim of this study was to investigate the effect of storage conditions on the sensory quality, colour and texture of fresh-cut cabbage during the addition of ascorbic acid, citric acid and calcium chloride. Ascorbic acid maintained the overall quality for 14 days at 0℃ and 7 days at 5℃;no difference, however, was observed regarding browning of cut surface compared to the control sample at both storage temperatures. Calcium chloride maintained the overall quality and cut surface browning for 14 days at both storage temperatures. It was also found that citric acid 1% can be used for minimally processed cabbage. Soaking with citric acid helped retain the color and increased the overall acceptance and organoleptic quality of fresh cut cabbage;it reduced browning of the cut surface and protected against formation of black specks. Citric acid treatment combined with low temperature storage (0℃) prolonged the shelf life of minimally processed cabbage for 22 days, time sufficient for acceptable marketing of the product. The lightness of minimally processed cabbage decreased linearly from 70.94 ± 6 to 63.8 ± 8.5 - 61.3 ± 8 units for the chemical treatments during 22 days of storage at 0℃. Hue angle values during storage time were also significantly influenced by chemical treatments mainly at 0℃.
基金Natural Science Foundation of Guangxi(2017GXNSFAA198082)Guangxi Aquatic Vegetable Fresh-keeping and Processing Engineering Research Center Project(GXSSSCBXYJGZX1912)。
文摘[Objectives]This study was conducted to investigate the effect of compound fresh-keeping liquid on the browning and quality of fresh-cut yam during the cold chain process.[Methods]Under the simulated cold chain condition of 4℃,a uniform design(U6*(64))experiment was carried out to optimize the compound preservative formula,and a better compound preservative formula was obtained using the regression equation.[Results]The compound preservative formula was:AA 0.25%,CA 0.5%,Nisin 0.09%,GSH 0.15%.The compound fresh-keeping liquid effectively delayed the browning of fresh-cut yam and the accumulation of MDA,maintained the content of TSS,inhibited the activity of PAL and delayed the appearance of the maximum activity of POD and POD.[Conclusions]This study provides technical support for the actual extension of the shelf life of fresh-cut yam.
基金the Monti Sibillini National Park for having funded this research, within the project “Censimento della coturnice (Alectoris graeca orlandoi) nel Parco Nazionale dei Monti Sibillini”
文摘Over the last several decades,the Mediterranean region has been subjected to mountain abandonment and farming cessation,leading to changes in vegetation and coenological features of grasslands,contextually to the strong decline of the rock partridge(Alectoris graeca).Our hypothesis was that the ongoing dynamic processes leading to the compositional changes of grasslands in central Apennines affect the habitat suitability for the singing male(territorial male defending its reproductive site).In 2015,we defined the presence/absence of spring territorial singing males in seven sites(1,250-2,400 m a.s.l.),by the census in 74 playback stations,distributed along 15 transects.We characterized the topography and the vegetation mosaic of such sites according to the collected topographic and vegetation cover data in 59 randomly selected plots(100 m×100 m)along the transects.To understand the relations among the environmental variables and the effect of the composition and dynamism of the vegetation mosaics on the presence/absence of the singing male,we used principal components analysis and generalized linear mixed-effect modelling.Our results emphasized the marked overlap between the general environmental conditions,which proved to define the habitat suitability for A.graeca,and the characteristics of the site chosen by the singing male for starting the reproductive activities.Moreover,we found that the site suitability for the singing male decreases when the vegetation recovery processes are ongoing,because of the spread of coarse tall grassesdominated communities and/or grassland types with dense turf.Tall grass-dominated communities and thick-turf grasslands exert their negative effect decreasing the habitat suitability for the singing male starting from low cover values.Therefore,it is conceivable that singing male’s suitable habitat will be dramatically restricted to the steepest south-facing slopes,where topographic and soil conditions do not allow the spread of grasslands with dense turf and of invasive/dominant tall grasses,increasing the threat to the species due to the effect of climate change on the vegetation features.
基金funded by Institute of Nature Conservation PASpartly by a Polish State Committee for Scientific Research/National Science Centre grant No.N N304 325836.
文摘The problem of habitat fragmentation is recently an important issue in ecological research as well as in the practical approach of nature conservation. According to the most popular approaches, habitats are considered as the homogenous parts of the landscape. Also the metapopulation concept problem of the inert habitat heterogenity is considered quite seldom. These approaches have some weak points resulting from the assumption that the border between habitat patches and the metapopulation matrix is fairly sharp. This paper presents a resource-based concept of habitats, based on mathematical theory of point processes, which can be easily applied to analysing the problem of uneven distribution of resources. The basic assumption is that the random distribution of resources may be mathematically described as the realisation of a certain point process. According to our method, it is possible to calculate the expected quantities of available resources as well as the minimum area of habitat that includes the expected abundance of the resource. This approach may be very useful to understand some crucial phenomena in landscape ecology, such as the patch size effect and its connection to habitat loss and fragmentation.
基金supported by grants from the National Key R&D Program of China(2019YFD0901202)the National Natural Science Foundation of China(grant Nos.32071584,32072982&32271658)the Program of Shanghai Academic Research Leader(21XD1405000).
文摘Background The provision of habitat for fishery species in estuaries is highly valued and represents one of the most challenging ecosystem service values to quantify.However,quantifying this value is challenging due to complex relationships between habitat change,ecological processes,and environmental variations.This study aims to estimate estuarine habitat degradation and its impact on the reproduction process of the crab Eriocheir sinensis by characterizing the changes in breeding habitat and investigating relationships between the species and its habitat in the Yang-tze River Estuary.Methods A species distribution model recently developed was applied to estimate the extent and quality of breeding habitat changes from 2014-2021.The intrinsic(physiological)and external(structural)reproductive attributes of the breeding process were measured to assess the effects of habitat change.The relationships among habitat change,reproductive attributes and environmental factors were analyzed to understand the underlying driving forces of habitat degradation for breeding process by multivariate statistical analysis.Results About 34.24%of essential habitat was lost,mainly in highly suitable areas due to reclamation and waterway construction.Habitat degradation significantly affects female distribution and their reproductive processes,particularly gonad development during the pre-reproductive period and fecundity during the reproductive period,without altering population structure.These results indicated that the main ecological function served by the highly suitable breeding ground was the provision for development of gonad and improvement of fecundity.Increases of salinity and turbidity,caused by hydrodynamic changes from large-scale waterway construction,were identified as the environmental determinants contributing to cumulative habitat degradation.These influences ultimately led to a decrease in the fecundity of E.sinensis.Conclusions Our research sheds light on the quantification of habitat degradation in the Yangtze River Estuary and its implications for the reproduction process of E.sinensis,which can serve as a foundation for assessing and quantifying the ecosystem service values provided by these breeding grounds.This information is valuable for policymakers and resource managers in making informed decisions regarding habitat conservation and the sustainable utilization of fishery resources.
