Changes In Nutrients Research Articles

Optimization and Detection of Freshness Biomarkers of Atlantic Salmon Subjected to Different Vacuum Packaging Conditions during Storage at 0 °C by Metabolomics and Molecular Docking.

The freshness of Atlantic salmon is influenced mainly by tissue metabolism, which in turn is affected by storage time and conditions. The alterations in taste profiles and nutritional values of salmon when packaged using vacuum methods have not been fully understood, and the factors contributing to these changes require further research. In this work, the extraction method for flavor nutrients from salmon was optimized via the Plackett-Burman (PB) test. A sensitive and rapid targeted metabolomics method for the simultaneous determination of 34 nutrients was successfully established via ultra-performance liquid chromatography-triple quadrupole/linear ion trap composite mass spectrometry (UHPLC-QTRAP/MS), and various nutritional compositions during storage at 0 °C under different vacuum conditions (0 kPa or -90 kPa) for 4 and 8 days were analyzed. Results showed that storage time had a significant effect on salmon metabolism. The total amino acids decreased by 62.95% and 65.89% at 0 kPa and -90 kPa, respectively. Notably, a marked reduction in histidine after 8 days at -90 kPa may have diminished bitterness, while decreased levels of umami-tasting amino acids like glutamine and aspartic acid affected the overall flavor profile. Overall, the packaging conditions at 0 °C and 0 kPa were more suitable for the preservation of most nutrients in salmon. Pathway enrichment analysis revealed that the reduction in substances was mainly related to the alanine, aspartate, and glutamate metabolism pathways. Alanine, inosine, and histidine, whose levels changed significantly, can bind to the typical umami taste receptor TIR1/TIR3 and can be biomarkers to monitor and determine the freshness or spoilage of salmon after 4-8 days of storage. This study revealed the changes in small-molecule nutrients in salmon during storage under different packaging conditions, which provides a reference for the packaging preservation technology of fresh salmon and new ideas for the evaluation of salmon quality and determination of freshness.

Manure-derived black soldier fly frass enhanced the growth of chilli plants (Capsicum annuum L.) and altered rhizosphere bacterial community

Sustainable manure management is crucial for minimising environmental impacts as the livestock industry expands to meet the increasing demand for protein. Black soldier fly (Hermetia illucens L.) larvae (BSFL) farming is an emerging waste management method that efficiently processes large volumes of organic waste, including manure, to produce valuable protein, oil and chitin products. Frass, a nutrient-rich by-product of black soldier fly farming, has potential as an organic fertiliser. However, research has primarily focused on frass derived from food waste, with little exploration of manure-derived BSFL frass. This study aimed to determine whether frass derived from manure could enhance the growth of chilli (Capsicum annuum L.) over 14 weeks under controlled glasshouse conditions. The impacts of manure-derived BSFL frass on soil properties and soil bacterial communities were characterised. The results indicated that a 0.6 % w/w application rate yielded the highest chilli plant biomass, with reduced growth observed at higher rates. The enhanced growth at optimal manure-derived BSFL frass application rates was due to increased nitrogen content, whereas reduced growth at higher rates was likely caused by phytotoxicity from not completely decomposed frass. Soil microbial biomass carbon and nitrogen also increased with manure-derived BSFL frass, implying microbial carbon and nitrogen immobilisation. Additionally, the changes in pH and nutrients due to manure-derived BSFL frass caused shifts in the bacterial community in the chilli plant rhizosphere, enriching the relative abundance of bacteria with potential growth-promoting properties. This study highlights the potential of integrating manure into black soldier fly waste management processes, demonstrating that manure-derived BSFL frass can be used as an organic fertiliser with circular economy benefits.

Balancing the nutrient needs: Optimising growth in Malus sieversii seedlings through tailored nitrogen and phosphorus effects.

The impact of nitrogen (N) and phosphorus (P) on the physiological and biochemical processes crucial for tree seedling growth is substantial. Although the study of plant hydraulic traits in response to N and P is growing, comprehensive research on their combined effects remains limited. Malus sieversii, a key ancestral species of modern apples and a dominant species in Xinjiang's Tianshan wild fruit forest, is witnessing a decline due to climate change, pests and diseases, compounded by challenges in seedling regeneration. Addressing this, a 4-year study was conducted to determine the optimal fertilisation method for it. The experiment explored varying levels of N (N10, N20 and N40) and P (P2, P4 and P8), and their combined effects (N20Px: N20P2, N20P4, N20P8; NxP4: N10P4, N20P4 and N40P4), assessing their impact on gas exchange, hydraulic traits, and the interplay among functional traits in Tianshan Mountains' M. sieversii seedlings. Our study revealed that All N-inclusive fertilisers slightly promoted the net photosynthetic rate. N10 significantly increasing leaf hydraulic conductivity. All P-inclusive fertilisers adversely affected hydraulic conductivity. P8, N20P4 and N20P8 notably increased seedlings' vulnerability to embolism. Seedlings can adaptively adjust multiple functional traits in response to nutrient changes. The research suggests N10 and N20 as the most effective fertilisation treatments for M. sieversii seedlings in this region, while fertilisation involving phosphorus is less suitable. This study contributes valuable insights into the specific nutrient needs of it, vital for conservation and cultivation efforts in the Tianshan region.

Effects of Fasting on THP1 Macrophage Metabolism and Inflammatory Profile.

Fasting can affect the body's inflammatory response, and this has been linked to potential health benefits, including improvements for people with rheumatic diseases. In this work, we evaluated, in vitro, how changes in nutrient availability alter the inflammatory response of macrophages. Macrophage-differentiated THP1 cells were cultured, deprived of FCS or subjected to cycles of FCS deprivation and restoration to mimic intermittent fasting. Changes in the macrophage phenotype, the cells' response to inflammatory stimuli and the level of mitochondrial alteration were assessed. The results indicate that while periods of serum starvation are associated with a decrease in IL1β and TNFα expression, consistent with an anti-inflammatory response, intermittent serum starvation cycles promote a pro-inflammatory phenotype. Rapid changes in reducing capacity and mitochondrial response were also observed. Of note, while some changes, such as the production of oxygen free radicals, were reversed with refeeding, others, such as a decrease in reducing capacity, were maintained and even increased. This study shows that different fasting protocols can have diverging effects and highlights that time-limited nutrient changes can significantly affect macrophage functions in cell cultures. These findings help elucidate some of the mechanisms by which specific fasting dietary interventions could help control inflammatory diseases.

Differential Strategies of Ectomycorrhizal Development between Suillus luteus and Pinus massoniana in Response to Nutrient Changes.

Ectomycorrhizal fungi employ different strategies for mycelial growth and host colonization under varying nutrient conditions. However, key genes associated with mycorrhizal interaction should be influenced solely by the inoculation treatment and not by nutrient variations. To utilize subtle nutrient differences and rapidly screen for key genes related to the interaction between Suillus luteus and Pinus massoniana, we performed an inoculation experiment using culture bottles containing high- and low-nutrient media. Interestingly, S. luteus LS88 promoted the growth of P. massoniana seedlings without mature ectomycorrhiza, and the impact of LS88 inoculation on P. massoniana roots was greater than that of nutrient changes. In this study, the resequenced genome of the LS88 strain was utilized for transcriptome analysis of the strain. The analysis indicated that a unique gene encoding glutathione S-transferase (GST) in LS88 is likely involved in colonizing P. massoniana roots. In this study, the GST gene expression was independent of nutrient levels. It was probably induced by P. massoniana and could be used as a marker for S. luteus colonization degree.

Effects of N, P and K fertilizations on bud nutrient concentrations and fruit set of sweet cherry trees

Factors such as pollinators, pollen quality, pollinator variety, high temperatures, and nutrients affect the fruit set in sweet cherry trees. In this study, the effects of different doses of N, P, and K applied from the soil on fruit set of sweet cherry were investigated. Flower bud minerals (N, P, K, Ca, Mg, Fe, Cu, Mn, Zn, and B), fruit set ratios (FSR), and yield values were determined to compare treatments for 3 years (2015–2017). FSR (%) and yield (kg/tree) values ​​ranged between 14.31–21.76 and 11.11–14.88 for N, 11.94–22.64 and 11.23–14.82 for P, 12.38–17.39 and 12.67–13.68 for K, respectively. N affected fruit bud N, Mg, Fe, Mn, and B concentrations, FSR and yield. Parameters other than FSR increased with increasing N doses and the highest values ​​were obtained from the highest N treatment. FSR of the highest N dose was the same as the control treatment, but lower in the other treatments. P affected fruit bud P and Mg concentrations, FSR and yield. Fruit bud P and Mg concentrations increased as compared to the control treatment. The change in FSR and yield values ​​could not be associated with the application dose, but showed linear changes with each other. K was effective only on FSR, the lowest values ​​were obtained at the highest dose, while it was similar at the other doses. Fruit set ratio of sweet cherry trees under present experimental conditions could not be associated with the change in fruit bud nutrients due to N, P and K fertilization.

Culinary evolution of cultured Takifugu Flavidus head soup: Nutrient dynamics and flavor profiles across cooking durations

This study aimed to examine the effects of different cooking durations on the nutrient composition and flavor profile of cultured Takifugu Flavidus head soup (CTHS). The dynamic changes of key nutrients and volatile organic compounds (VOCs) in CTHS during a 180-min cooking process were meticulously tracked using chemical analysis and headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). The results revealed a continuous increase in the content of proteins, lipids, sugars, amino acids (AAs), and fatty acids (FAs) in CTHS with extended cooking time, while the diversity and concentration of VOCs fluctuated. The unique flavor of CTHS was primarily attributed to the presence of key aldehyde compounds, such as (E,Z)-2,4-decadienal, (E,E)-2,4-decadienal, and decanal, with their levels declining after 120 min. Correlation analysis and principal component analysis (PCA) revealed a strong correlation between nutrients and VOCs. The increased levels of AAs and FAs exacerbated FA oxidation and Maillard reactions, thereby promoting the formation of key VOCs, especially after 90 min. In summary, controlling cooking duration is essential to establish a balance between nutrition and flavor in traditional cooking methods; the optimal quality CTHS can be achieved by cooking for 120 min. This study provided critical insights for enhancing the culinary quality and health benefits of traditional soups, while offering a scientific reference for gastronomy enthusiasts and the food industry.

Effects of the rice-mushroom rotation pattern on soil properties and microbial community succession in paddy fields.

Currently, straw biodegradation and soil improvement in rice-mushroom rotation systems have attracted much attention. However, there is still a lack of studies on the effects of rice-mushroom rotation on yield, soil properties and microbial succession. In this study, no treatment (CK), green manure return (GM) and rice straw return (RS) were used as controls to fully evaluate the effect of Stropharia rugosoannulata cultivation substrate return (SRS) on soil properties and microorganisms. The results indicated that rice yield, soil nutrient (organic matter, organic carbon, total nitrogen, available nitrogen and available potassium) and soil enzyme (urease, saccharase, lignin peroxidase and laccase) activities had positive responses to the rice-mushroom rotation. At the interannual level, microbial diversity varied significantly among treatments, with the rice-mushroom rotation significantly increasing the relative alpha diversity index of soil bacteria and enriching beneficial microbial communities such as Rhizobium, Bacillus and Trichoderma for rice growth. Soil nutrients and enzymatic activities were significantly correlated with microbial communities during rice-mushroom rotation. The fungal-bacterial co-occurrence networks were modular, and Latescibacterota, Chloroflexi, Gemmatimonadota and Patescibacteria were closely related to the accumulation of nutrients in the soil. The structural equation model (SEM) showed that fungal diversity responded more to changes in soil nutrients than did bacterial diversity. Overall, the rice-mushroom rotation model improved soil nutrients and rice yields, enriched beneficial microorganisms and maintained microbial diversity. This study provides new insights into the use of S. rugosoannulata cultivation substrates in the sustainable development of agroecosystems.

Something to talk about; crosstalk disruption at the neurovascular unit during HIV infection of the CNS

Abstract Although treatable with antiretroviral therapy, HIV infection persists in people living with HIV (PLWH). It is well known that the HIV virus finds refuge in places for which antiretroviral medications do not reach therapeutic levels, mainly the CNS. It is clear that as PLWH age, the likelihood of developing HIV-associated neurological deficits increases. At the biochemical level neurological dysfunction is the manifestation of altered cellular function and ineffective intercellular communication. In this review, we examine how intercellular signaling in the brain is disrupted in the context of HIV. Specifically, the concept of how the blood-brain barrier can be a convergence point for crosstalk, is explored. Crosstalk between the cells of the neurovascular unit (NVU) (endothelium, pericytes, astrocytes, microglia and neurons) is critical for maintaining proper brain function. In fact, the NVU allows for rapid matching of neuronal metabolic needs, regulation of blood-brain barrier (BBB) dynamics for nutrient transport and changes to the level of immunosurveillance. This review invites the reader to conceptually consider the BBB as a router or convergence point for NVU crosstalk, to facilitate a better understanding of the intricate signaling events that underpin the function of the NVU during HIV associated neuropathology.

Functional Nutrients and Jujube-Based Processed Products in Ziziphus jujuba.

Jujube (Ziziphus jujuba Mill.) is the first tree species in China, with a long history and abundant yield. However, fresh jujubes have a short shelf-life and are not resistant to storage. Therefore, more and more processed jujube products are being studied. These processed products can extend the shelf-life of jujubes and attract widespread attention for their rich functional nutrients. This review summarized changes in nutrients of fresh jujube and processed products and the research progress of different preparation methods of jujubes. Meanwhile, the pharmacological effects of bioactive components in jujube-based products were concluded. Jujube and its processed products contain rich polysaccharides, vitamin C, and other functional nutrients, which are beneficial to humans. As the initial processing method for jujubes, vacuum freezing or microwave drying have become the most commonly used and efficient drying methods. Additionally, processed jujube products cannot be separated from the maximum retention of nutrients and innovation of flavor. Fermentation is the main deep-processing method with broad development potential. In the future, chemical components and toxicological evaluation need to be combined with research to bring consumers higher quality functional jujube products and ensure the sustainable development of the jujube industry.

Comparison of different drying methods for Wushan Codonopsis pilosula: Changes in color, microstructure, nutrients, bioactive compounds, and volatile

This study evaluated the effects of different drying methods, namely hot air drying (HAD), heat pump drying (HPD), microwave drying (MD), vacuum freeze drying (VFD), and sun drying (SD) on the quality of Wushan Codonopsis pilosula (WCP). Results showed that HAD and HPD were effective in retaining the alcohol -soluble leachate content, with the retention rates of 91.76 % and 91.32 %, respectively. The most attractive appearance was observed in VFD-WCP. There was no significant difference between the polysaccharide content of VFD-WCP and HPD-WCP, which were 202.62 mg/g and 201.71 mg/g, respectively. MD and SD were detrimental to the retention of color, physicochemical indicators, and atractylenolide III. The content of lobetyolin was increased significantly (P < 0.05) after drying, following this trend: HPD > HAD > VFD > MD > SD > Fresh. The aroma characteristics of WCP were altered by the drying process. However, the principal component analysis (PCA) showed that HAD and HPD produce similar aromatic characteristics with traditional SD. Overall, HPD shows promise as a replacement for SD, not only for increasing drying efficiency but also for improving the quality of WCP.

Seed yield as a function of cytokinin-regulated gene expression in wild Kentucky bluegrass (Poa pratensis)

BackgroundKentucky bluegrass (Poa pratensis L.) panicle development is a coordinated process of cell proliferation and differentiation with distinctive phases and architectural changes that are pivotal to determine seed yield. Cytokinin (CK) is a key factor in determining seed yield that might underpin the second “Green Revolution”. However, whether there is a difference between endogenous CK content and seed yields of Kentucky bluegrass, and how CK-related genes are expressed to affect enzyme regulation and downstream seed yield in Kentucky bluegrass remains enigmatic.ResultsIn order to establish a potential link between CK regulation and seed yield, we dissected and characterized the Kentucky bluegrass young panicle, and determined the changes in nutrients, 6 types of endogenous CKs, and 16 genes involved in biosynthesis, activation, inactivation, re-activation and degradation of CKs during young panicle differentiation of Kentucky bluegrass. We found that high seed yield material had more meristems compared to low seed yield material. Additionally, it was found that seed-setting rate (SSR) and lipase activity at the stage of spikelet and floret primordium differentiation (S3), as well as 1000-grain weight (TGW) and zeatin-riboside (ZR) content at the stages of first bract primordium differentiation (S1) and branch primordium differentiation (S2) showed a significantly positive correlation in the two materials. And zeatin, ZR, dihydrozeatin riboside, isopentenyl adenosine and isopentenyl adenosine riboside contents were higher in seed high yield material than those in seed low yield material at S3 stage. Furthermore, the expressions of PpITP3, PpITP5, PpITP8 and PpLOG1 were positively correlated with seed yield, while the expressions of PpCKX2, PpCKX5 and PpCKX7 were negatively correlated with seed yield in Kentucky bluegrass.ConclusionsOverall, our study established a relationship between CK and seed yield in Kentucky bluegrass. Perhaps we can increase SSR and TGW by increasing lipase activity and ZR content. Of course, using modern gene editing techniques to manipulate CK related genes such as PpITP3/5/8, PpLOG1 and PpCKX2/5/7, will be a more direct and effective method in Kentucky bluegrass, which requires further trial validation.

CemR atypical response regulator impacts energy conversion in Campylobacteria.

C. jejuni and A. butzleri are closely related pathogens that infect the human gastrointestinal tract. In order to infect humans successfully, they need to change their metabolism as nutrient and respiratory conditions change. A regulator called CemR has been identified, which helps them adapt their metabolism to changing conditions, particularly oxygen availability in the gastrointestinal tract so that they can produce enough energy for survival and spread. Without CemR, these bacteria, as well as a related species, Helicobacter pylori, produce less energy, grow more slowly, or, in the case of C. jejuni, do not grow at all. Furthermore, CemR is a global regulator that controls the synthesis of many genes in each species, potentially allowing them to adapt to their ecological niches as well as establish infection. Therefore, the identification of CemR opens new possibilities for studying the pathogenicity of C. jejuni and A. butzleri.

Widely targeted metabolomics analysis of nutrient changes in a new black rice variety ‘Huamoxiang No.3’ (Oryza sativa L. var. Glutinosa Matsum) under different cooking modes

AbstractBackgroundBlack rice is rich in various nutrients, such as anthocyanins, which may undergo some changes during cooking. However, previous studies have been mainly focused on a single substance and paid less attention to the changes in overall nutrient components. Here, we performed widely targeted metabolomics analysis on the chemical compositional changes in a new black rice variety (‘Huamoxiang No.3’) under three cooking modes, including bottom heating (BH), induction heating (IH), and IH + pressure.ResultsAmong the detected 1458 metabolites, 276 and 108 metabolites were differential metabolites after cooking and in three cooking modes, respectively. Cooking increased the contents of most peptides, phenolic acids, and organic acid compounds but significantly decreased those of lipids and flavonoids, particularly anthocyanins. However, phenolic acids such as chlorogenic acid, erucic acid, and p‐coumaric acid increased significantly, possibly due to the release of bound phenols and degradation of flavonoids to phenolic acids, such as thermal degradation of C3G to protocatechuic acid and among the three heating modes, the IH + pressure mode resulted in the most significant changes.ConclusionAlthough cooking reduced the content of flavonoids and anthocyanins, the increase in phenolic acids and other substances contributed to the healthy effect of cooked black rice, and the content of these active substances increased more significantly in the IH + pressure mode.

Deciphering the therapeutic actions of Brenania brieyi (Rubiaceae) fractions on oxidoinflammatory anomalies

A decline in the antioxidant network during the inflammatory response plays a critical role in the pathogenesis of numerous diseases. We designed this study to decipher the therapeutic efficacy of Brenania brieyi in reducing oxidative stress caused by the inflammatory response to cotton pellets. Graded doses of methanol and chloroform fractions of B. brieyi (MFBB and CFBB) and indomethacin were administered to Wistar rats for seven days after implanting sterilised cotton pellets (20 mg). Thereafter, biochemical indices of oxidative stress were determined using blood samples taken through cardiac puncture. Furthermore, molecular interactions, drug-likeness, and toxicity features of B. brieyi phytochemicals were also assessed. Compared with the untreated group, the groups treated with MFBB and CFBB had a significant (p &amp;lt; 0.05) decrease in granuloma tissue weight and MDA levels while increasing glutathione levels, SOD, and CAT activities. In addition, a substantial increase in inflammatory-induced changes in antioxidant nutrients, together with a decline in liver enzymes, was obtained in the treated groups. The docking tests revealed that the top-scoring phytoconstituents of B. brieyi, n-hexadecanoic acid, and 9-octadecanoic acid interacted well with catalase, having docking scores of -6.19 and -7.58 kcal/mol, respectively. Moreover, the hits had good oral drug-likeness features and a safe toxicity profile. The findings of the study provide evidence that B. brieyi has antioxidant and anti-inflammatory properties, suggesting that it could be used as an alternative therapy to regulate oxidative stress-related diseases.

Changes in daily intake of nutrients and foods including confectionery after the initiation of empagliflozin in Japanese patients with type 2 diabetes: a pilot study

IntroductionIt is unclear how dietary intake changes after sodium-glucose cotransporter 2 inhibitor (SGLT2i) treatment is started in patients with type 2 diabetes.MethodsWe performed a non-controlled, open-label study that enrolled 51 patients with type 2 diabetes. The patients were newly administered empagliflozin, and their dietary habits were examined using a self-administered diet history questionnaire at the beginning of the study and after 24 weeks. We investigated the association of changes in HbA1c and body weight with changes in energy, nutrient, and food group intakes.ResultsAt 24 weeks after the start of the study, HbA1c improved significantly and body weight decreased. In the food group, only the intake of confectionery increased, and there were no significant differences in the association between changes in HbA1c and body weight and changes in energy, nutrient, and food group intakes after 24 weeks. However, a significant negative correlation was found between change in HbA1c after 4 weeks and change in energy intake after 24 weeks, and principal component analysis showed an association between change in HbA1c levels after 4 weeks and change in energy intake and some food group intakes including confectionery after 24 weeks.ConclusionIn this study, after 24 weeks of treatment with empagliflozin, only intake of confectionery increased. Early assessment by dietitians after initiation of SGLT2i treatment might be important because our data suggested that the reduction in blood glucose levels after the start of empagliflozin was associated with a subsequent increase in energy intake.Trial registrationUniversity Hospital Medical Information Network-Clinical Trials Registry (UMIN-CTR) on September 5, 2016 (registration ID, UMIN000002309|| http://www.umin.ac.jp/ctr/).

Response of soil fungal communities and their co-occurrence patterns to grazing exclusion in different grassland types.

Overgrazing and climate change are the main causes of grassland degradation, and grazing exclusion is one of the most common measures for restoring degraded grasslands worldwide. Soil fungi can respond rapidly to environmental stresses, but the response of different grassland types to grazing control has not been uniformly determined. Three grassland types (temperate desert, temperate steppe grassland, and mountain meadow) that were closed for grazing exclusion for 9 years were used to study the effects of grazing exclusion on soil nutrients as well as fungal community structure in the three grassland types. The results showed that (1) in the 0-5 cm soil layer, grazing exclusion significantly affected the soil water content of the three grassland types (P < 0.05), and the pH, total phosphorous (TP), and nitrogen-to-phosphorous ratio (N/P) changed significantly in all three grassland types (P < 0.05). Significant changes in soil nutrients in the 5-10 cm soil layer after grazing exclusion occurred in the mountain meadow grasslands (P < 0.05), but not in the temperate desert and temperate steppe grasslands. (2) For the different grassland types, Archaeorhizomycetes was most abundant in the montane meadows, and Dothideomycetes was most abundant in the temperate desert grasslands and was significantly more abundant than in the remaining two grassland types (P < 0.05). Grazing exclusion led to insignificant changes in the dominant soil fungal phyla and α diversity, but significant changes in the β diversity of soil fungi (P < 0.05). (3) Grazing exclusion areas have higher mean clustering coefficients and modularity classes than grazing areas. In particular, the highest modularity class is found in temperate steppe grassland grazing exclusion areas. (4) We also found that pH is the main driving factor affecting soil fungal community structure, that plant coverage is a key environmental factor affecting soil community composition, and that grazing exclusion indirectly affects soil fungal communities by affecting soil nutrients. The above results suggest that grazing exclusion may regulate microbial ecological processes by changing the soil fungal β diversity in the three grassland types. Grazing exclusion is not conducive to the recovery of soil nutrients in areas with mountain grassland but improves the stability of soil fungi in temperate steppe grassland. Therefore, the type of degraded grassland should be considered when formulating suitable restoration programmes when grazing exclusion measures are implemented. The results of this study provide new insights into the response of soil fungal communities to grazing exclusion, providing a theoretical basis for the management of degraded grassland restoration.

A dataset of monthly litter recovery from the desert grassland in Southern Tarim Basin during 2010–2020

The Cele National Field Science Observation and Research Station of Desert Grassland Ecosystem of Xinjiang of Chinese Academy of Science (Hereinafter referred to as "Cele Station"), is located on the southern margin of the Tarim Basin bordered to the south by the Kunlun Mountains and to the north by the largest desert in China, the Taklimakan Desert. As a result of simple vegetation community and slow accumulation of soil organic matter, litter serves as an important source of nutrients in this area. Based on the long-term observations of desert plant communities at Cele station, we gathered monthly dynamic data of litter recovery in the desert grassland from Southern Tarim Basin from 2010 to 2020. Based on plant organs (branches, leaves, and fruits), the monthly dynamic data of litter recovery at the observation sites and plots were sorted out, and the annual changes of community and soil nutrients were recorded. Data were compiled in strict accordance with CERN bio-observation specifications. The data has undergone review and quality control by the quality control personnel of the station and sub-center. The results would provide basic data for further study of litter dynamics in the desert grassland from Southern Tarim Basin, and theoretical support for better understanding and assessing nutrient cycling in hyper–arid desert ecosystems.

Morphological and Physiological Changes under NaCl Stress in Some Pyrus and Quince Rootstocks

In this study, the aim was to determine some morphological, physiological, and biochemical changes in non-grafted plants of OHxF 97, OHxF 333, Fox 11, and BA 29 rootstocks under NaCl stress. NaCl (0 mM, 20 mM, 40 mM, and 80 mM) was applied to the rootstocks planted in 18-liter pots with irrigation water repeated over two years. Under NaCl stress, plant height, plant diameter, and leaf area decreased in all rootstocks. Additionally, Fox 11 and BA 29 rootstocks were more adversely affected by NaCl stress to leaf necrosis. The amounts of chl a, chl b, and total chl decreased in Fox 11 rootstock with moderate and severe stress treatments. Carotenoid content in the leaves, especially under severe stress conditions, showed a decrease in Pyrus rootstocks. Under NaCl stress, the leaves of Fox 11 were rich in proline. MDA content generally increased with NaCl stress compared to the control in Fox 11 and BA 29. Although significant changes in plant nutrients were generally not observed with NaCl, a significant decrease in the amount of K+ in the leaves of Fox 11 was identified. Consequently, Fox 11 and BA 29 rootstocks exhibit sensitivity to NaCl stress, whereas OHxF rootstocks demonstrate greater tolerance.

Time since fire affects ecological stoichiometry of plant–soil–microbial systems of Betula platyphylla, a pioneer species in burnt areas of China’s boreal forest

Plant stoichiometry and nutrient allocation may reflect adaptation strategies to environmental nutrient changes. Fire, as a major disturbance in forests, mediates soil nutrient availability that may influence plant nutrient dynamics. However, plant–soil stoichiometric allocation strategies during different post-fire periods and the effects of soil, enzymes, and microbial biomass on plant stoichiometry are largely unknown. The pioneer tree species Betula platyphylla in burnt forests of northern China was the object of this study, and severely burned areas selected with different fire years. Nearby unburned areas acted as a control. Carbon (C), nitrogen (N), and phosphorus (P) contents in leaves, branches, and fine roots and rhizosphere soil, C-, N- and P-acquiring enzyme activities were examined. Microbial biomass C, N, and P were measured, and factors influencing C:N:P stoichiometry of plants during the burned area restoration were explored. Our results show that C and N contents in leaves increased with time since fire, while C and P in branches and C, N and P in fine roots decreased. Activities of C-, N-, and P-acquiring enzymes and microbial biomass N increased with time since fire. Redundancy analysis showed that changes in soil N-acquiring enzyme activity, microbial biomass C, and N had significant effects on plant ecological stoichiometry. These results show a significant flexibility in plant nutrient element allocation strategies and C:N:P stoichiometric characteristics. Soil extracellular enzyme activity drives the changes in stoichiometry during the process of post-fire restoration.