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Animals ◽  
2022 ◽  
Vol 12 (2) ◽  
pp. 198
Author(s):  
Beata Paszczyk ◽  
Magdalena Polak-Śliwińska ◽  
Anna E. Zielak-Steciwko

The aim of the study was to compare and demonstrate whether commercial rennet ripening cheeses available on the market in summer and winter differ in their chemical composition, fatty acid profile, content of cis9trans11 C18:2 (CLA) acid and other trans isomers of C18:1 and C18:2 acid and whether they are characterized by different values of lipid quality assessment indices. The experimental material consisted of rennet ripening of cheeses produced from cow’s milk available in the Polish market. The first batch contained cheeses produced in winter and purchased from the market between May and June. The second batch contained cheeses produced in summer and purchased between November and December. Chemical composition was analyzed by FoodScan apparatus. The gas chromatography (GC) method was used to determine the content of fatty acids. Results obtained in the presented study indicate that the chemical composition, content of fatty acids trans isomers, and lipid quality indices varied between summer and winter cheeses. The summer cheeses were richer sources of MUFA and PUFA compared to winter cheeses. Summer cheeses were also characterized by lower content of SFA, higher content n-3, lower n-6/n-3 ratio, and higher content of DFA. Higher contents of CLA and trans C18:1 and C18:2 were found in summer cheeses.


2022 ◽  
Vol 8 ◽  
Author(s):  
Yiquan Yuan ◽  
Xiuzhen Li ◽  
Zuolun Xie ◽  
Liming Xue ◽  
Bin Yang ◽  
...  

Blue carbon (C) ecosystems (mangroves, salt marshes, and seagrass beds) sequester high amounts of C, which can be respired back into the atmosphere, buried for long periods, or exported to adjacent ecosystems by tides. The lateral exchange of C between a salt marsh and adjacent water is a key factor that determines whether a salt marsh is a C source (i.e., outwelling) or sink in an estuary. We measured salinity, particulate organic carbon (POC), and dissolved organic carbon (DOC) seasonally over eight tidal cycles in a tidal creek at the Chongming Dongtan wetland from July 2017 to April 2018 to determine whether the marsh was a source or sink for estuarine C. POC and DOC fluxes were significantly correlated in the four seasons driven by water fluxes, but the concentration of DOC and POC were positively correlated only in autumn and winter. DOC and POC concentrations were the highest in autumn (3.54 mg/L and 4.19 mg/L, respectively) and the lowest in winter and spring (1.87 mg/L and 1.51 mg/L, respectively). The tidal creek system in different seasons showed organic carbon (OC) export, and the organic carbon fluxes during tidal cycles ranged from –12.65 to 4.04 g C/m2. The intensity showed significant seasonal differences, with the highest in summer, the second in autumn, and the lowest in spring. In different seasons, organic carbon fluxes during spring tides were significantly higher than that during neap tides. Due to the tidal asymmetry of the Yangtze River estuary and the relatively young stage, the salt marshes in the study area acted as a strong lateral carbon source.


Water ◽  
2022 ◽  
Vol 14 (2) ◽  
pp. 217
Author(s):  
Xiaomei Su ◽  
Alan D. Steinman ◽  
Yunlin Zhang ◽  
Hong Ling ◽  
Dan Wu

Sediment nutrients can be released to the surface water when hydraulic disturbance becomes strong in shallow lakes, which contributes to nutrient enrichment and subsequent lake eutrophication in the water column. To explore the seasonal variations and spatial distributions exhibited by nutrients in the water column, surface sediment, and pore water of Lake Yangcheng and its major tributaries, we determined the concentrations of nitrogen (N) and phosphorus (P) throughout the lake in different seasons of 2018. Total N (TN) and total P (TP) concentrations in the connected rivers were much greater than those in the lake, indicating that external loading greatly contributed to the nutrient enrichment. TN concentration in the water column was highest in the winter, whereas TP peaked in the summer. A similar temporal pattern was observed for TN and TP in the sediment with maxima in the winter and minima in the summer; however, nutrients in the pore water were highest in the summer, in contrast to the temporal variation in the sediment. Additionally, high TN values in the water column and high TP in the three compartments were distributed primarily in the west part of the lake, while high TN concentrations in the sediment and pore water were observed mainly in the east portion of the lake. According to the enrichment factor index (an indicator evaluating the nutrient enrichment by comparing the detected contents and standard values), nutrients in the lake sediment were severely enriched with TN and TP averaging 2195.8 mg/kg and 543.0 mg/kg, respectively. The vertical distribution of TN and TP generally exhibited similar decreasing patterns with an increase in sediment depth, suggesting mineralization of TN and TP by microbes and benthic organisms. More attention and research are needed to understand the seasonality of nutrient exchange across the sediment–water interface, especially in eutrophic lakes.


2022 ◽  
Vol 10 (1) ◽  
pp. 88
Author(s):  
José Enrique Gutiérrez-Romero ◽  
Jerónimo Esteve-Pérez

The reduction of ship pollutants is a key issue in the international agenda. Emissions estimation is usually based on standard calculations that consider the different scenarios of ships. This work presents research on the influence of added resistance on ship emissions and freight throughput. First, a methodology to assess the added resistance influence is shown. The procedure is applied to a roll on-roll off ship under two load conditions. Analyses are computed to value wind- and wave-added resistances for different seasons. An investigation on ship pollutant emissions for a whole route is performed. Moreover, the influence of added resistance on the ship freight throughput is analyzed. Finally, some relevant information is concluded. For instance, a difference of up to 53% in pollutant emission estimation is observed if added resistance is considered. Additionally, the navigation in added resistance conditions could lead to a freight loss of 18% per operational year.


Animals ◽  
2022 ◽  
Vol 12 (2) ◽  
pp. 142
Author(s):  
Gonzalo Medina-Vogel ◽  
Francisco Muñoz ◽  
Meredith Moeggenberg ◽  
Carlos Calvo-Mac ◽  
Macarena Barros-Lama ◽  
...  

Two main challenges when controlling alien American mink (Neovison vison) in Patagonia are to maximize campaign efficacy and cost-effectiveness and to avoid trapping native species. We designed and tested new variants of collapsible wire box traps, compared the efficacy of a food-based bait and a scent lure and compared catch rates in different seasons of the year. We used the data to model the efficiency rate of the trapping and to determine the trapping effort required to remove 70–90% of the estimated discrete mink population. Between January 2018 and March 2021, we operated 59 trapping transects over 103 three-day trapping periods in southern Chile. Traps were first baited with canned fish, and afterwards with mink anal gland lure. We compared the efficacy of mink capture with that of our previous study. We trapped 196 mink (125 males, 71 females), with most captures in summer. The medium-sized GMV-18 trap caught more male mink, but the more compact GMV-13 caught fewer non-target rodents and no native mammals. The scent lure was more successful than the canned fish when the previous campaign’s data were included in the analysis. There was also a significant improvement in the proportion of female mink trapped and reduced labour compared with our previous campaign that used larger traps, fish bait and 400–500 m trap spacings. We caught relatively more females than males after the third night of trapping on a transect. Our data analysis supports the use of the GMV-13 variant of wire cage trap as the best trap size: it is effective on female mink, small, cheap and easy to transport. Combined with mink anal scent lure, it reduces the possibility of trapping native species compared with other traps tested in Chile. As the most efficient method for removing at least 70% of the estimated discrete mink population within the area covered by each trap transect in southern Chile tested to date, we recommend trapping campaigns using GMV-13 during summer, with a 200-m trap spacing, for up to 6 days before moving traps to a new site, with a combination of three days with a female scent gland lure, followed by three days with a male scent gland lure.


2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Hamed Dadkhah-Aghdash ◽  
Hassan Zare-Maivan ◽  
Mehdi Heydari ◽  
Mohsen Sharifi ◽  
Manuel Esteban Lucas-Borja ◽  
...  

AbstractSoils and oak trees (Quercus brantii Lindl.) in Zagros forests are suffering from the air pollution caused by the Ilam Gas Refinery. Thus, for the first time, we investigated the contamination level of sulfur and trace elements in these ecosystems. Sampling of soil and tree leaves was carried out in different seasons of 2019 and at different distances from the gas refinery. The results showed that soils and leaves at the various distances compared with control distance (10,000 m) were more affected by the gas refinery. Distance from the pollution source and physicochemical properties of soils were the main factors affecting contamination of soil elements contents. The soils with pollution load indices (PLI) of 4.54 were in the highly polluted category. Sulfur was at highly polluted category in soils and were highly enriched in trees. The trees mainly absorbed studied elements via their aerial organs. Our findings indicated that oak trees with the highest value of metal accumulation index are influence tools for monitoring various elements in the polluted air produced by the gas refinery. It is recommended that the ecosystem components near the refinery be studied to accurately evaluate disorders in the food chain.


Water ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 108
Author(s):  
Marilena Sanfilippo ◽  
Marco Albano ◽  
Antonio Manganaro ◽  
Gioele Capillo ◽  
Nunziacarla Spanò ◽  
...  

Transitional water environments represent very ecologically interesting areas, which provide various ecosystem services, both concerning biodiversity protection and sustainable fruition of resources. In this way, the evaluation of total carbon and its components, chlorophyll, and chemical and physical parameters is of fundamental importance to deepen the dynamics of these peculiar natural areas. Commercial interests linked to the biological resources of these areas are often not well exploited in relation to their sustainability, due to lack of knowledge. In this study, we investigated the distribution of total organic carbon, chlorophyll, and other related physical and chemical parameters in the natural Lagoon of Capo Peloro (Eastern Sicily), to deepen the knowledge on the carbon equilibrium of these transitional basins. Collected data showed different trends for all parameters, mainly related to different seasons and water exchanges with sea. The influences of primary production sources and farmed molluscs were not negligible and deserve to be further investigated in the future. The results obtained reveal good margins for the possibility of environmentally sustainable exploitation of natural resources in both basins, but at the same time, there is a need for a more detailed knowledge of anthropogenic impacts on the area.


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