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1.
J Environ Manage ; 361: 121265, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38820788

ABSTRACT

Rapid urban expansion and economic development challenges to the sustainability of ecosystem services (ESs), a solid understanding of the mechanisms that drive ESs helps policymakers to respond. However, few existing studies on ES-driven mechanisms emphasize the integration of natural and cultural services, with most neglecting spatial non-stationarity at the geographic scale. Here, we improved the ROS model to quantify cultural ecosystem services (CES) and developed a comprehensive ecosystem services index (CESI) by coupling CES with 6 typical natural ESs (carbon storage (CS), water yield (WY), nitrogen export (NE), soil conservation (SC), habitat quality (HQ), food supply (FS)), subsequently, Spearman's correlation and MGWR were employed to reveal the CESI-driven mechanism considering geographic scales. The results showed that: (1) From 2000 to 2020, CS, WY, SC, and HQ exhibited decline, which contrasts with the significant increase in CES. (2) The CESI showed a decreasing trend (3.28-3.70) while the coefficient of variation was increasing over time (0.11-0.15). The overall spatial distribution of CESI shows higher northwest than southeast, with strong spatial autocorrelation. (3) The CESI exhibits synergistic associations with CS, SC, HQ, and CES (0.54-0.83), and forms trade-offs with WY, NE, and FS. (4) Climate, vegetation, landscape, human, and topography have significant effects on CES and CESI with a significantly geographic scale differences, especially areas closer to the sea exhibit heightened sensitivity. Besides, the combined effects of multiple factors are stronger than any individual driver. The results emphasize the necessity of introducing ecological land in coastal cities and establishing natural reserves in high CESI areas to maintain diversity. The study improves the CES assessment methodology and proposes an integrated analytical framework that combines natural and cultural ESs with geographic-scale drivers, providing a new perspective on the analysis of ESs mechanisms.


Subject(s)
Conservation of Natural Resources , Ecosystem , China , Cities , Soil/chemistry
3.
Heart Surg Forum ; 26(5): E478-E484, 2023 Oct 07.
Article in English | MEDLINE | ID: mdl-37920094

ABSTRACT

BACKGROUND: Ventricular septal rupture (VSR) following myocardial infarction (MI) is a rare but lethal complication. We analyzed the long-term results and risk factors for survival in the treatment of VSR. METHODS: From January 2012 to December 2021, 115 consecutive patients with post-MI VSR were admitted to our hospital. Depending on different treatment methods patients were divided into following three groups: medical, transcatheter intervention, and surgical repair. During the study, relevant clinical data, operation-related conditions, and follow-up data were analyzed. The Kaplan-Meier method and log-rank test were used to determine the cumulative incidence of mortality. The independent risk factors for patient mortality were evaluated by multivariate logistic regression. RESULTS: The mean follow-up time was 43.4 ± 34.7 months. The overall in-hospital, 30-day, and long-term mortality rates were 24.3%, 38.3%, and 51.3%, respectively. In the medical group, the in-hospital and 30-day mortality rates were 46.7 % (21/45) and 82.2 % (37/45), respectively, with only three patients alive at follow-up. In the transcatheter intervention group, 30-day and long-term mortality rates were 12% and 28%, respectively. In the surgical repair group, 30-day and long-term mortality rates were 8.9% and 22.2%, respectively. Compared with the surgery-group patients, patients with transcatheter intervention had a longer time from VSR to intervention. Logistic regression analysis revealed that age, previous infarction, Killip class, serum creatinine, Troponin T, N-terminal pro-B-type natriuretic peptide, and medical strategy were risk factors for all-cause mortality. CONCLUSIONS: The 30-day and long-term outcomes of patients treated with surgical repair and transcatheter intervention were significantly better than medically treated patients.


Subject(s)
Myocardial Infarction , Ventricular Septal Rupture , Humans , Follow-Up Studies , Ventricular Septal Rupture/diagnosis , Ventricular Septal Rupture/etiology , Ventricular Septal Rupture/surgery , Retrospective Studies , Myocardial Infarction/surgery , Risk Factors , Treatment Outcome
4.
J Environ Manage ; 345: 118904, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37659371

ABSTRACT

The negative impacts of conventional agriculture and the imperative to adopt conservation tillage garnered significant attention. However, the effects of conservation tillage on soil enzyme activities still lack comprehensive cognition. Here, we collected 14,308 pairwise observations from 369 publications worldwide to systematically evaluate the effects of different conservation tillage practices (reduced tillage (T), reduced tillage with straw return (TS), reduced tillage with straw mulch return (TSO), no-tillage (NT), no-tillage with straw return (NTS), and no-tillage with straw mulch return (NTSO)) on the activities of 35 enzymes in soil. The results showed that: (1) the effect of conservation tillage on soil enzyme activity varied by enzyme type, except for peroxidase (-12.34%), which showed an overall significant positive effect (10.28-89.76%); (2) the NTS and TS demonstrated strong potential to improve soil enzyme activities by increasing a wide variety of soil enzyme activities (12-15) and efficacy (9.76-75.56%) than other conservation tillage (8.60-68.68%); (3) in addition, the effect of conservation tillage on soil enzyme activity was regulated by soil depth, crop type, years of conservation tillage, climate (mean annual precipitation and temperature), and soil physicochemical properties (e.g., pH, bulk density, electrical conductivity, organic matter, ammonium nitrogen, total phosphorus, available phosphorus, total potassium, available potassium, etc.). Overall, our quantitative analysis clearly suggests that conservation tillage is an effective measure for improving soil enzyme activity on global croplands, where combination of reduced tillage or no-till with straw return are considered to have great potential and promise. The results contribute to better comprehend the effects of conservation tillage on soil activity and provide a valuable insight for agricultural management.


Subject(s)
Agriculture , Soil , Climate , Phosphorus , Potassium
5.
Sci Total Environ ; 903: 166177, 2023 Dec 10.
Article in English | MEDLINE | ID: mdl-37572896

ABSTRACT

The evergreen broad-leaf forest is subtropical zonal vegetation in China, and its species diversity and stability are crucial for maintaining forest ecosystem functions. The region is generally affected by global changes such as high levels of nitrogen deposition. Therefore, it is critical to determine the adaptation strategies of subtropical dominant species under nitrogen addition. Here, we conducted two-year field experiments with nitrogen addition levels as 0 kg N ha-1 yr-1 (CK), 50 kg N ha-1 yr-1 (LN) and 100 kg N ha-1 yr-1 (HN). We investigated the effects of nitrogen addition on leaf functional traits (including nutrition, structural and physiological characteristics) of five dominant species in subtropical evergreen broad-leaf forest. Results suggested that the effect of nitrogen addition on leaf functional traits was species-specific. Contrary to Rhododendron delavayi and Eurya muricata, Quercus glauca, Schima superba and Castanopsis eyrei all responded more to the HN treatment than LN treatment. Compared to other leaf functional traits, leaf anatomical structure traits had the highest average plasticity (0.246), and the relative effect of leaf photosynthetic property was highest (7.785) under N addition. Among the five species, S. superba was highest in terms of the index of plasticity for leaf functional traits under nitrogen addition, followed by Q. glauca, E. muricata, C. eyrei and R. delavayi. The major leaf functional traits representing the economic spectrum of leaves (LES) showed resource acquisitive strategy (high SLA, LNC, LPC, Pn) and conservative strategy (high LTD, LDMC, C/N) clustering on the opposite ends of the PCA axis. The PCA analysis indicated that species with high leaf plasticity adopt resource acquisitive strategy (S. superba and Q. glauca), whereas species with low leaf plasticity adopt resource conservative strategy (E. muricata, C. eyrei and R. delavayi). In aggregate, resource-acquisitive species benefit from nitrogen addition more than resource-conservative species, suggesting that S. superba and Q. glauca will occupy the dominant position in community succession under persistently elevated nitrogen deposition.

6.
Sci Rep ; 13(1): 8182, 2023 May 20.
Article in English | MEDLINE | ID: mdl-37210377

ABSTRACT

Soil erosion (SE) is one of the most serious disasters in the world, which directly damage the productivity of the land and affect human well-being. How to effectively mitigate soil erosion is a challenge faced by all countries in the world. In this study, soil erosion was quantitatively assessed base on the RULSE model in an ecologically fragile area [Xiushui watershed (XSW)], and the effects of three major categories of factors (land use/cover change, landscape fragmentation and climate) on soil erosion were investigated using correlation analysis and structural equation model. The results indicated that there was no continuous increase or decrease trend on the SE of XSW with impact of rainfall, the mean values of SE were 2205.27 t/ha, 3414.25 t/ha and 3319.44 t/ha from 2000 to 2020 and the hot areas of SE were mainly distributed around the Xiushui river channel, respectively. The expansion of urbanization (the area of impervious increased from 113.12 to 252.57 km2) aggravated landscape fragmentation, and the landscape fragmented area had some overlap with the hot zone of SE. Additionally, the LUCC factor dominated by NDVI, landscape fragmentation factor and climate factor dominated by rainfall had a directly driving effect on SE, where the path coefficient of landscape fragmentation was 0.61 (P < 0.01), respectively. We also found that except increasing forest area, improving forest quality (NDVI, canopy closure, structure) deserved emphasized in SE management, and the effect of landscape fragmentation on SE also should not be ignored. Moreover, soil erosion assessment at large scales over long time periods tends to underestimate the driving force of rainfall on SE, and it is a great challenge to evaluate the effect of extreme rainfall on soil erosion at short time scales in a downscale manner. This research provides insights for ecological sustainable management and soil erosion protection policies.

7.
J Inflamm Res ; 16: 1825-1836, 2023.
Article in English | MEDLINE | ID: mdl-37131410

ABSTRACT

Objective: The association between serum uric acid (sUA) and incident abdominal aortic calcification (AAC), and severe abdominal aortic calcification (SAAC) in the general population of the United States (US) is unclear. Therefore, this research aimed to investigate the association between sUA and the risk of AAC and SAAC. Methods: Individuals from National Health and Nutrition Examination Survey (NHANES) database were analyzed cross-sectionally between 2013 and 2014. The restricted cubic spline (RCS), multivariable logistic regression model and subgroup analysis were utilized to evaluate the correlation between sUA and incident AAC, and SAAC. In addition, generalized additive models with smooth functions were employed to survey the relationship between sUA and the degree of AAC. Results: This study included 3016 individuals from the NHANES database. According to the RCS plot, sUA levels were associated with the risk of AAC/SAAC in a U-shaped pattern in the US population. The degree of calcification decreased at first and then increased with the increase in the sUA level. Conclusion: Close monitoring and adequate control of sUA levels in the US general population may reduce the risk of AAC and SAAC.

8.
Sci Rep ; 13(1): 4585, 2023 03 20.
Article in English | MEDLINE | ID: mdl-36941404

ABSTRACT

The purpose of this study was to explore the use of aspirin in conjunction with various statins for cardiovascular disease (CVD) prevention in the general population of the United States (U.S.). A total of 3778 people from the National Health and Nutrition Examination Surveys from 2011 to 2018 were included in our analysis. After adjusting for sociodemographic and common cardiovascular risk factors, we used multivariable logistic regression analysis to determine aspirin should be combined with which type of statin for better CVD preventive effects. Subgroup analyses were carried out subsequently. In comparison to the aspirin use alone, the odds ratios with 95% confidence intervals for CVD were 0.43 (0.33, 0.57), 0.69 (0.42, 1.13), 0.44 (0.31, 0.62), 0.34 (0.23, 0.50) and 0.64 (0.49, 0.84) for the combination use of aspirin and atorvastatin, lovastatin, pravastatin, rosuvastatin as well as simvastatin, respectively, in the fully-adjusted model. Aspirin combined with rosuvastatin was more effective in the prevention of individual CVD, including congestive heart failure, coronary heart disease, angina pectoris and heart attack, than aspirin combined with other statins. In conclusion, statins combined with aspirin have a clear advantage over aspirin alone in preventing CVD. In addition, when various sex, age, and fitness levels were considered, as well as with and without diabetes mellitus, the combination usage of aspirin and rosuvastatin had the greatest CVD preventive effects than aspirin coupled with other statins.


Subject(s)
Cardiovascular Diseases , Hydroxymethylglutaryl-CoA Reductase Inhibitors , Humans , United States/epidemiology , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Rosuvastatin Calcium/therapeutic use , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/prevention & control , Cardiovascular Diseases/chemically induced , Aspirin/therapeutic use , Simvastatin/adverse effects
9.
Int J Clin Pract ; 2023: 1621873, 2023.
Article in English | MEDLINE | ID: mdl-36815008

ABSTRACT

In the American population, the relationship between the standardized serum 25-hydroxyvitamin D (25(OH)D) concentration and the risk of abdominal aortic calcification (AAC) is unclear. The purpose of our study was to investigate the relationship between serum 25(OH)D concentration and AAC risk. Participants from the National Health and Nutrition Examination Survey (NHANES) between 2013 and 2014 were analyzed cross sectionally. An analysis of the relationship between serum 25(OH)D concentration and incident AAC and severe AAC (SAAC) was based on the restricted cubic spline (RCS) and multivariable logistic regression model. In addition, generalized additive models with smooth functions were used to evaluate the relationship between serum 25(OH)D concentration and the degree of AAC. Finally, a subgroup analysis was conducted. There were a total of 3,040 individuals in our study. The serum 25(OH)D concentration was divided into quartiles (Q1: 9.37-50.5 nmol/L; Q2: 50.6-67.2 nmol/L; Q3: 67.3-85.8 nmol/L; and Q4: 85.9-318.0 nmol/L); the lowest quartile served as the reference group (Q1). After adjusting for known confounding variables, compared with the lowest quartile (Q1) of serum 25(OH)D concentration, the odds ratios with 95% confidence intervals for AAC and SAAC across the quartiles (Q2, Q3, and Q4) were (1.042 (0.812, 1.338), 0.863 (0.668, 1.115), and 1.022 (0.787, 1.327)) and (1.48 (0.87, 2.52), 1.70 (1.01, 2.92), and 2.13 (1.19, 3.86)), respectively. As shown by the RCS plot, the serum 25(OH)D concentration was associated with the risk of AAC/SAAC in a U-shaped pattern (P for nonlinearity <0.05). In addition, the degree of AAC decreased at first and then increased as the serum 25(OH)D concentration increased. In conclusion, a U-shaped relationship existed between serum 25(OH)D concentration and the risk of AAC and SAAC. Consequently, the risk of AAC and SAAC may be mitigated with regular monitoring and vitamin D supplementation.


Subject(s)
Vitamin D Deficiency , Vitamin D , Humans , United States , Nutrition Surveys , Cross-Sectional Studies , Risk Factors
10.
Postgrad Med ; 135(1): 50-57, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36154549

ABSTRACT

OBJECTIVE: Association between neutrophil-to-lymphocyte ratio (NLR) on admission and poor prognosis in patients with acute heart failure (AHF) has been well established. However, the relationship between dynamic changes in NLR and in-hospital mortality in AHF patients has not been studied. Our purpose was to determine if an early change in NLR within the first week after AHF patients was admitted to intensive care unit (ICU) was associated with in-hospital mortality. METHODS: Data from the medical information mart for intensive care IV (the MIMIC-IV) database was analyzed. The effect of baseline NLR on in-hospital mortality in critical patients with AHF was evaluated utilizing smooth curve fitting and multivariable logistic regression analysis. Moreover, comparison of the dynamic change in NLR among survivors and non-survivors was performed using the generalized additive mixed model (GAMM). RESULTS: There were 1169 participants who took part in the present study, 986 of whom were in-hospital survivors and 183 of whom were in-hospital non-survivors. The smooth curve fitting revealed a positive relationship between baseline NLR and in-hospital mortality, and multivariable logistic regression analysis indicated that baseline NLR was an independent risk factor for in-hospital mortality (OR 1.04, 95% CI 1.02,1.07, P-value = 0.001). After adjusting for confounders, GAMM showed that the difference in NLR between survivors and non-survivors grew gradually during the first week after ICU admission, and the difference grew by an average of 0.51 per day (ß = 0.51, 95% CI 0.45-0.56, P-value <0.001). CONCLUSIONS: Baseline NLR was associated with poor prognosis in critical patients with AHF. Early rises in NLR were linked to higher in-hospital mortality, which suggests that keeping track of how NLR early changes might help identify short-term prognosis of critical patients with AHF.


Subject(s)
Lymphocytes , Neutrophils , Humans , Hospital Mortality , Retrospective Studies , Prognosis
11.
Front Plant Sci ; 13: 1055721, 2022.
Article in English | MEDLINE | ID: mdl-36466239

ABSTRACT

Polygonatum cyrtonema is a medicinal and edible herb rich in polysaccharides, steroidal saponins, and flavonoids that has been widely used as a food, vegetable, and medicine over the years. Although previous studies have preliminarily explored the metabolic and transcriptional regulatory mechanisms of the main secondary metabolites in P. cyrtonema, the complex mechanism of microRNA (miRNA)-mediated posttranscriptional regulation remains unclear. Metabolome analysis showed that iso-ophiopogonanone B, (25S)-pratioside D1, disporopsin, and isodiosgenin-Glc-Glc, which are associated with intermediates in the flavonoids and saponins pathways, were significantly upregulated in the stem and leaf compared with the rhizome, and most saccharides, including arabinose, cellobiose, maltotetraose, and panose, showed the opposite trend, suggesting that they may contribute to the formation and accumulation of the main active ingredients in P. cyrtonema. We found that 4-hydroxymandelonitrile have a relatively good inhibitory effect on α-glucosidase, indicating that it may play a role in hypoglycemic functions. Transcriptome and weighted gene coexpression network analysis (WGCNA) were combined to reveal several candidate genes involved in the accumulation of polysaccharides, saponins, and flavonoids, including PcSQLE, PcCYP71A1, PcSUS, PcFK, and PcMYB102. Integrated analyses of miRNAs and messengerRNAs (mRNAs) showed that novel_miR14, novel_miR49, novel_miR75, and aof_miR164 were negatively correlated with alpha-linolenic acid metabolism and the mitogen activated protein kinase (MAPK) signaling pathway, including PcAOS, PcSPLA2, PcFRK1, and PcDELLA, indicating that these miRNAs may coordinately regulate the biosynthesis of other secondary metabolites in P. cyrtonema. These findings will facilitate in-depth research on the functions of these miRNAs and mRNAs related to the main active substances for pathological and biological regulation, which will be beneficial to provide theoretical guidance for the molecular breeding of P. cyrtonema.

12.
Am J Transl Res ; 14(7): 5024-5039, 2022.
Article in English | MEDLINE | ID: mdl-35958489

ABSTRACT

OBJECTIVE: Myocardial ischemia is the stoppage or insufficiency of blood flow to the myocardium, depriving cells of oxygen supply which leads to their apoptosis or death. Currently, the management of patients has improved, making it possible to reduce myocardial infarction injury with new strategies of reperfusion and pharmacologic treatment. METHODS: A rat model of myocardial ischemia and reperfusion injury (MIRI) was created and subjected to cryptotanshinone (CRY) with or without JAK1 inhibitor filgotinib (FILGO) treatment. H&E staining was used for histopathologic evaluation of heart injury, and TTC staining was employed for evaluation of the infarct size. Western blotting and immunofluorescence were used to measure the protein expression and qRT-PCR for determining mRNA expression. RESULTS: CRY significantly reduced the area of the infarct, the number of apoptotic cells, and the concentrations of lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) induced by ischemia/reperfusion (I/R). Subsequent analysis showed that CRY repressed the expression of caspase-12, CHOP, and GRP78, but enhanced the phosphorylation of JAK and STAT3. However, FILGO treatment markedly abolished the beneficial effect of CRY pretreatment on cardiomyocyte damage, apoptosis, cardiac function, and inhibition of endoplasmic reticulum stress (ERS)-dependent apoptosis marker proteins. CONCLUSION: CRY may alleviate MIRI by inhibiting ERS-dependent apoptosis by activating the JAK1/STAT3 signaling pathway.

13.
Front Cardiovasc Med ; 9: 933103, 2022.
Article in English | MEDLINE | ID: mdl-35928932

ABSTRACT

Objective: To analyze the survival and risk factors associated with the surgical treatment of ventricular septal rupture (VSR) after acute myocardial infarction (AMI). Methods: We retrospectively analyzed 45 consecutive patients with VSR after AMI whose procedures were performed in the Department of Cardiovascular Surgery at the General Hospital of Northern Theater Command between January 2012 and December 2021. Relevant clinical data, surgery-related conditions, and follow-up data of all patients were summarized. Patients were divided into the survival group and the death group. The Kaplan-Meier method and log-rank test were used to determine the cumulative incidence of all-cause mortality. Multivariate logistic regression was used to evaluate the independent risk factors for all-cause mortality. Results: The average postoperative follow-up time was 42.1 ± 34.1 months. The overall mortality rate was 20% (9/45 patients) and the operative mortality rate was 8.9% (4/45 patients). Logistic analysis showed that the death group had higher serum creatinine (127.32 ± 47.82 vs. 82.61 ± 27.80 µmol/L, respectively; P = 0.0238) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) [8,654.00 pg/mL (6,197.00-11,949.00 pg/mL) vs. 4,268.96 pg/mL (1,800.00-7,894.00 pg/mL), respectively; P = 0.0134] levels than the survival group. The cardiopulmonary bypass time (CPB) was longer in the death group than in the survival group [131.00 min (121.00-184.00 min) vs. 119.00 min (103.00-151.50 min), respectively; P = 0.0454]. Significantly more red blood cells were transfused in the death group than in the survival group [11.60 units (6.10-16.50) vs. 3.75 units (0.00-7.00 units), respectively; P = 0.0025]. Intra-aortic balloon pump (IABP) implantation (P = 0.016) and ventilation time (P = 0.0022) were risk factors for mortality. A 1-month landmark analysis showed that compared with patients with VSR to surgical time >14 days, patients who underwent surgery within 14 days had a higher rate of all-cause mortality (25.00 vs. 3.33%; log-rank P = 0.023). Patients with VSR within 14 days also had a higher rate of residual shunts that were higher than moderate. Multivariate analysis showed that transfusion of red blood cells and NT-proBNP level were risk factors for all-cause mortality, as well as major adverse cardiovascular and cerebrovascular events. Conclusions: Surgical repair resulted in good outcomes for patients with VSR after AMI. Patients with VSR to surgical time >14 days had a lower rate of all-cause mortality. Treatment strategies for VSR should be based on the patient's condition and comprehensively determined through real-time evaluation and monitoring.

14.
Ying Yong Sheng Tai Xue Bao ; 33(2): 337-343, 2022 Feb.
Article in Chinese | MEDLINE | ID: mdl-35229506

ABSTRACT

Both nitrogen (N) and phosphorus (P) are the main limiting elements for plant growth in terrestrial ecosystems. Fine roots play a critical role in plant growth. To reveal the effects of combined N and P addition on fine root traits of Machilus pauhoi, we performed a field N and P addition experiment in the midmonth from April to September in 2016 and 2017 in a 3-year M. pauhoi forest (N and P supply ratios were 8:1, 10:1, 12:1, 15:1). Both fine root morphological traits (specific root length, specific root area, average diameter, root tissue density) and stoichiometric traits (total carbon content, total nitogen content and carbon-nitrogen ratio) were analyzed. The results showed that the effects of combined application of N and P on fine root raits varied with seasons. In June, fertilization significantly increased specific root area, total nitrogen content and specific root length of 0-1 mm fine root, but decreased root tissuse density, carbon-nitrogen ratio and average diameter of 0-1 mm root. The most obvious change of fine root traits in June was found under the treatment with a N and P supply ratio of 12:1. In December, combined N and P addition significantly increased root tissue density, total nitrogen content, carbon-nitrogen ratio as well as fine root biomass with the diameter of 0-1 mm. The results of principal component analysis showed that different N and P supply ratios exerted different effects on the relationships among fine root traits. Fine root traits were distributed at both ends of Axis 1 when treated with 12:1 N:P, while distributed at Axis 1 and Axis 2 under other treaments. There was a significant negative correlation between fine root average diameter variation and the relative plant growh rate. The relationship among fine root traits, and between fine root traits and the relative growth rate of plant biomass were optimally coordinated at the treament with a N:P ratio of 12:1.


Subject(s)
Nitrogen , Phosphorus , Biomass , Ecosystem , Forests , Nitrogen/analysis , Plant Roots , Soil
15.
Ying Yong Sheng Tai Xue Bao ; 33(1): 25-32, 2022 Jan.
Article in Chinese | MEDLINE | ID: mdl-35224922

ABSTRACT

Trees are characterized with selective absorption of different forms of nitrogen. Ammonium nitrogen (NH4+-N) and nitrate nitrogen (NO3--N) are the main forms of nitrogen for plant absorption. We examined the differences of absorption between NH4+-N and NO3--N for 1-year-old Machilus pauhoi seedlings planted in local hilly red soil in a pot experiment. A controlled experiment with 7 different NH4+-N/NO3--N treatments was conducted, to study the effects of nitrogen forms and different NH4+-N/NO3--N ratios on the growth and leaf traits of M. pauhoi seedlings. The results showed that there were no significant differences in the relative growth rate of ground diameter (GD), plant height (TH), and biomass (RGR) of M. pauhoi seedlings with different NH4+-N/NO3--N ratios for four months, but these parameters were relatively high under the treatment of NH4+-N:NO3--N=5:5. The seedlings of M. pauhoi didn't show obvious preference for NH4+-N and NO3--N in short term. The extremely low NH4+-N/NO3--N ratio application was unsuitable for their growth. Different NH4+-N/NO3--N application had significant effects on leaf area (LA), specific leaf area (SLA), leaf dry matter content (LDMC), leaf relative water content (LRWC), net photosynthetic rate (Pn), intercellular CO2 concentration (Ci), water use efficiency (WUE), and photosynthetic nitrogen use efficiency (PNUE). M. pauhoi seedlings under the treatment of NH4+-N:NO3--N=1:9 had the highest LA, SLA, Pn, WUE and PNUE. However, the seedlings under the treatment of NH4+-N:NO3--N=9:1 had the lowest LDMC, leaf tissue density (LTD), LRWC and Ci. Different NH4+-N/NO3--N combined application did not affect leaf nitrogen content (LN) and leaf phosphorus content (LP), which were highest under the treatment of NH4+-N:NO3--N=5:5. Across different NH4+-N/NO3--N combined treatments, GD, TH, and RGR were significantly negatively correlated with SLA, while both GD and RGR were significantly negatively correlated with PNUE. Our results could provide theoretical basis for precise nutrient management and high-efficiency cultivation techniques during the seedling stage of the M. pauhoi.


Subject(s)
Ammonium Compounds , Lauraceae , Nitrates , Nitrogen , Plant Leaves , Seedlings
16.
Hortic Res ; 92022 Jan 05.
Article in English | MEDLINE | ID: mdl-35178562

ABSTRACT

Sapindus mukorossi is an environmentally friendly plant and renewable energy source whose fruit has been widely used for biomedicine, biodiesel, and biological chemicals due to its richness in saponin and oil contents. Here, we report the first chromosome-scale genome assembly of S. mukorossi (covering ~391 Mb with a scaffold N50 of 24.66 Mb) and characterize its genetic architecture and evolution by resequencing 104 S. mukorossi accessions. Population genetic analyses showed that genetic diversity in the southwestern distribution area was relatively higher than that in the northeastern distribution area. Gene flow events indicated that southwest species may be the donor population for the distribution areas in China. Genome-wide selective sweep analysis showed that a large number of genes are involved in defense responses, growth and development, including SmRPS2, SmRPS4, SmRPS7, SmNAC2, SmNAC23, SmNAC102, SmWRKY6, SmWRKY26, and SmWRKY33. We also identified several candidate genes controlling six agronomic traits by genome-wide association studies, including SmPCBP2, SmbHLH1, SmCSLD1, SmPP2C, SmLRR-RKs, and SmAHP. Our study not only provides a rich genomic resource for further basic research on Sapindaceae woody trees but also identifies several economically significant genes for genomics-enabled improvements in molecular breeding.

17.
Front Plant Sci ; 12: 692484, 2021.
Article in English | MEDLINE | ID: mdl-34367215

ABSTRACT

Sapindus mukorossi Gaertn., an important oleaginous woody plant, has garnered increasing research attention owing to its potential as a source of renewable energy (biodiesel). Leaf structural traits are closely related to plant size, and they affect the fruit yield and oil quality. However, plant size factors that predominantly contribute to leaf structural traits remain unknown. Therefore, the purpose of this study was to understand the associations between leaf structural traits and plant size factors in even-aged stands of S. mukorossi. Results showed that leaf length (LL) and leaf area (LA) markedly increased with the increasing diameter at breast height (DBH) and tree height (TH), although other leaf structural traits did not show noticeable changes. Difference in slopes also indicated that the degree of effect of plant size factors on leaf structural traits was in the order of TH > DBH. Leaf structural traits showed no systematic variation with crown width (CW). LA was significantly positively correlated with LL, leaf width (LW), LL/LW, and leaf thickness (LT) and was significantly but negatively correlated with leaf tissue density (LTD) and leaf dry mass content (LDMC). Specific leaf area showed a significantly negative correlation with LT, LDMC, and LTD. LTD showed a significantly positive correlation with LDMC, but a negative correlation with LT. The results were critical to understand the variability of leaf structural traits with plant size, can provide a theoretical foundation for further study in the relationship between leaf structural traits and fruit yield, and regulate leaf traits through artificial management measures to promote plant growth and fruit yield.

18.
J Environ Manage ; 281: 111849, 2021 Mar 01.
Article in English | MEDLINE | ID: mdl-33360924

ABSTRACT

Parks are a major public service infrastructure for urban residents. Due to the unbalance geographic distribution of public parks within an urban, residents may have uneven access to this service. Despite there has been an efflorescent literature references, there is no consensus on how to properly measure the accessibility of park. The traditional place-based or infrastructure-based approach is often criticized for inappropriately defining spatial units or threshold distances. Taking a fast urbanization region-Fuzhou City, China as a case, this study overcomes this deficiency by employing the method of two-step floating catchment area (2SFCA) to evaluate the park accessibility using mobile phone data (during December 10, 2018 to December 16, 2018), which is people-based information with actual park users' origin-destination trajectory of park users. The results indicate that the threshold distance is 2 km from the visitors' home to park regardless of level, and the total number of visitors is relative fewer in weekend than that in workdays. The spatial distribution of park effective area presents a notably decreasing trend from the urban center to its periphery; however, the spatial distribution of park accessibility is more scattered and irregular. Finally, different key factors of park accessibility are identified for different locations using Geographically weighted regression (GWR) technique. Our study has a good implication for urban park planner and manager to implement differentiated planning policies for parks with full consideration of holistic factors.


Subject(s)
Cell Phone , Parks, Recreational , China , Cities , Humans , Urbanization
19.
Ying Yong Sheng Tai Xue Bao ; 31(12): 4051-4057, 2020 Dec.
Article in Chinese | MEDLINE | ID: mdl-33393241

ABSTRACT

We analyzed the contents and stoichiometric ratios of carbon (C), nitrogen (N) and phosphorus (P) in leaves and fine roots of Machilus pauhoi (an evergreen broad-leaved species), Cerasus campanulata (a deciduous broad-leaved species) and Fokienia hodginsii (an evergreen coniferous species) to compare the leaf and root stoichiometry and allometric relationship between different functional groups of trees. There were significant difference in the contents and stoichiometry of C, N and P in the leaves and fine roots among different functional groups. C content, C/N and C/P of the leaves and roots were the highest in M. pauhoi. N content and N/P of the leaves and roots were the highest in C. campanulata, whereas P content of the leaves and roots was the highest in F. hodginsii. The allometric relationship of C, N and P contents as well as their stoichiometric ratios between the leaves and fine roots showed significant difference, which was affected by functional difference. The allometric relationship between C/P and N/P with significantly different allometric indexes in leaves in seedlings of those three tree species, while the isometric relationship between the contents of N and P was found in fine roots. There were significant difference in the C, N and P stoichiometry between the leaves and fine roots. The allometric relationship between leaf C content and root P content in M. pauhoi was detected. C and N contents and C/N, N/P in leaves generally had the allometric or isokinetic relationships with C/N, N/P of fine roots. There were allometric relationships between the leaf C content and the root C, N and P contents in F. hodginsii. It was concluded that nutrient allocation between leaves and fine roots of C. campanulata was more strongly coordinated. The investment strategy of P for leaves and fine roots across those three tree species was similar. The results provided scientific reference for accurate nutrient management at seedling stage and efficient cultivation technique.


Subject(s)
Nitrogen , Phosphorus , Carbon , Plant Leaves , Plant Roots , Seedlings , Trees
20.
Ying Yong Sheng Tai Xue Bao ; 30(11): 3627-3634, 2019 Nov.
Article in Chinese | MEDLINE | ID: mdl-31833674

ABSTRACT

Fine roots are sensitive to changes in the soil environment, and play an important role in plant growth and development. To clarify the relationship between fine root traits and rhizosphere soil nutrient characteristics, fine roots of trees belonging to different diameter classes in six-year-old Zenia insignis plantation were sampled. The results showed that root biomass, root length density and root volume density increased with the increases of diameter class. Specific root length and specific root area showed the trend of first rising and then falling and rising again with the increases of diameter class. Root tissue density did not change with diameter class. There were significant diffe-rences in soil pH, water content, total carbon, total phosphorus, ammonium nitrogen, nitrate nitrogen and total available nitrogen contents of rhizosphere soil belonging to different diameter classes. The concentrations of soil total carbon, total nitrogen, nitrate nitrogen and total available nitrogen in the rhizosphere soil of large diameter trees were relatively higher, while the soil water content, total phosphorus and ammonium nitrogen contents of small diameter trees were relatively higher. The concentrations of soil total nitrogen, total carbon, nitrate nitrogen and total available nitrogen were significantly positively correlated with root biomass, root length density and root volume density. The concentrations of soil total phosphorus was significantly positively correlated with root tissue density of fine roots, but negatively correlated with specific root length and specific root area. Soil water content was significantly positively correlated with root biomass and root volume density. Soil pH was significantly positively correlated with the specific root length and specific root area of fine roots, but negatively correlated with root tissue density. Our results provide scientific basis for the selection of excellent germplasm resources of Z. insignis.


Subject(s)
Rhizosphere , Soil , Biomass , Nitrogen , Nutrients , Plant Roots , Trees
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