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1.
Tob Induc Dis ; 21: 154, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026499

RESUMO

INTRODUCTION: Smoking cessation (SC) clinics are a professional SC services in China. However, studies comparing the characteristics and SC rates of smoking populations in SC clinics with those using mobile SC programs are limited. We compared smokers' characteristics, 3-month SC rates, and the factors influencing 3-month SC success, between a large hospital SC clinic and a WeChat SC mini-program. METHODS: Between January and November 2021, 384 participants voluntarily enrolled in either the hospital SC clinic (Group A: n=243) or the WeChat SC mini-program (Group B: n=141). Both groups underwent a 3-month SC intervention, and their SC status was monitored at 24 hours, 1 week, 1 month, and 3 months after quitting. SC rate was defined as the self-reported rate of continuous SC. RESULTS: The 3-month SC rate was higher in Group A (42.4%) than in Group B (24.8%). Participants with middle school education had a lower likelihood of SC success than those with primary school or lower (p=0.014). Employees in the enterprise/business/services industries were more likely to have SC success than farmers (p=0.013). Participants with SC difficulty scores of 0-60 were more successful than those with scores >60 (p=0.001, p=0.000, respectively). Participants who quit smoking due to their illness, or other reasons, had a higher likelihood of SC success than those who quit due to concerns about their own and their family's health (p=0.006, p=0.098, respectively). While the likelihood of SC success was lower in those who quit because of the influence of their environment than in those who quit due to concerns about their own and their family's health (p=0.057). CONCLUSIONS: Both SC clinics and WeChat SC mini-programs achieved satisfactory SC rates. The high accessibility of mobile SC platforms, which save time spent on transportation and medical visits, renders them worth promoting and publicizing as additional SC options for smokers, particularly young smokers.

2.
Front Endocrinol (Lausanne) ; 14: 1239903, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37859985

RESUMO

Introduction: The clinical impact of SARS-CoV-2 infection on human reproduction remains controversial. This prospective cohort study aimed to assess the effect of prior female SARS-CoV-2 infection on subsequent in vitro fertilization (IVF) outcomes. Materials and methods: A total of 451 women who underwent fresh IVF treatment between December 1, 2022 and April 30, 2023 were included from an academic fertility center. Participants were divided into the infected group if they had a prior COVID-19 history before cycle initiation (n = 252), while the control group were those uninfected (n = 199). The primary outcomes were the number of oocytes retrieved and clinical pregnancy rate after fresh embryo transfer. Multivariate linear and logistic regression analyses were conducted to control for potential confounders. Results: The number of oocytes retrieved (11.4 ± 8.3 vs. 11.6 ± 7.7; P = 0.457) and clinical pregnancy rate (70.3% vs. 73.7%; P = 0.590) were similar between infected and uninfected groups, with a fully adjusted ß coefficient of 0 (95% confidence interval [CI]: -0.14-0.13) and odds ratio of 0.64 (95% CI: 0.20-2.07), respectively. Consistently, the two groups were comparable in cycle characteristics as well as other laboratory and pregnancy parameters. In both subgroup analyses and restricted cubic splines, different post-infection time intervals to IVF cycle initiation showed no significant associations with treatment outcomes. Conclusion: Prior SARS-CoV-2 infection in females had no adverse influence on subsequent IVF treatment, regardless of the time interval following infection. Our findings provide reassurance for infected women planning for assisted reproduction. Additional prospective cohort studies with larger datasets and longer follow-up are required to confirm the conclusion.


Assuntos
Coeficiente de Natalidade , COVID-19 , Gravidez , Feminino , Humanos , Estudos Prospectivos , Indução da Ovulação , Estudos Retrospectivos , COVID-19/complicações , COVID-19/terapia , SARS-CoV-2 , Fertilização in vitro
3.
Tob Induc Dis ; 21: 49, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37057059

RESUMO

INTRODUCTION: Many smokers in China desire to quit, though the success rate among adults is low. This study evaluated the effects of QuitAction, a WeChat smoking cessation platform, summarized the intervention experience of the smoking cessation platform, identified aspects of the platform that necessitated improvement, and provided references for further optimization of the smoking cessation platform. METHODS: This single-arm study was conducted in Hunan, China, from September 2020 to October 2021. Regular smokers, who were aged ≥15 years and willing to quit smoking using QuitAction, were recruited. An in-application questionnaire evaluated participants' baseline smoking status and intention to quit smoking. The QuitAction program included questionnaires regarding the participants' ongoing smoking cessation status at 24 hours, one week, one month and three months after quitting. The smoking cessation procedure was discontinued if the participant had no intention of continuing. The smoking cessation rate, influencing success factors, frequency of use satisfaction, and helpfulness of QuitAction were recorded. RESULTS: A total of 303 participants registered and logged into the QuitAction program, including 59 with incomplete information and 64 with no intention of quitting. The study finally included 180 participants. The smoking cessation rate was 33.9% at 24 hours, 27.2% at one week, 26.1% at one month, and 25.0% at three months. QuitAction was reported as helpful by 94.9% of participants and 95.7% were satisfied with the program. Participants with a quitting difficulty score of 80-100 were less likely to quit smoking than participants with a difficulty score of 0-60 (OR=0.28; 95% CI: 0.10-0.78; p=0.015). Participants using the platform ≥5 times were more likely to quit smoking than those who used the platform <5 times (OR=3.59; 95% CI: 1.51-8.52; p=0.004). CONCLUSIONS: The QuitAction platform provides smoking cessation services that can improve smokers' success rate and improve user experience satisfaction.

4.
Tob Induc Dis ; 21: 43, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36969983

RESUMO

INTRODUCTION: Travel and living environment restrictions, which may have positive or negative effects on smoking-related behaviors, were implemented to limit the COVID-19 pandemic. This study aimed to compare the baseline clinical characteristics and smoking cessation (SC) rate at 3 months of patients in an SC clinic in Hunan Province, China before and during the COVID-19 pandemic and identify influencing factors of successful SC. METHODS: Healthy patients at the SC clinic aged ≥18 years before the COVID-19 pandemic and during the COVID-19 pandemic were divided into groups A and B, respectively. The two groups' demographic data and smoking characteristics were compared, and SC interventions were applied by the same medical staff team through telephone follow-up and counselling during the SC procedure. RESULTS: Groups A and B included 306 and 212 patients, respectively, with no significant differences in demographic data. The SC rates of group A (pre COVID-19) and group B (during the COVID-19 pandemic) at 3 months were 23.5% and 30.7%, respectively, after the first SC visit. Those who chose to quit immediately or within 7 days were more successful than those who did not choose a quit date (p=0.002, p=0.000). Patients who learned about the SC clinic via network resources and other methods were more likely to succeed than those who learned about the clinic from their doctor or hospital publications (p=0.064, p=0.050). CONCLUSIONS: Planning to quit smoking immediately or within 7 days of visiting the SC clinic and learning about the SC clinic via the network media or other methods improved the likelihood of successful SC. SC clinics and the harm of tobacco should be promoted via network media. During consultation, the smokers should be encouraged to quit smoking immediately and establish an SC plan, which would help them to quit smoking.

5.
Mol Biol Rep ; 50(4): 3045-3051, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36680622

RESUMO

BACKGROUND: The effect of a novel brain-derived peptide, hypoxic-ischemic brain damage associated peptide (HIBDAP), on apoptosis after oxygen-glucose deprivation (OGD) in PC12 cells was investigated. METHODS: The HIBDAP sequence (HSQFIGYPITLFVEKER) was coupled with the carrier peptide of the transactivator of transcription (TAT) sequence (YGRKKRRQRRR). FITC-labelled TAT-HIBDAP was observed by fluorescence microscopy. After TAT-HIBDAP treatment and OGD treatment, the PC12 cell apoptosis rate was analysed using lactate dehydrogenase (LDH) leakage and Annexin V-fluorescein isothiocyanate (FITC) assays. Mitochondrial membrane potential (ΔΨm) was examined by fluorescence microscopy. Protein expression of apoptotic factors was examined by Western blotting. RESULTS: FITC-labelled TAT-HIBDAP entered the PC12 cell nucleus. Compared with the OGD group, TAT-HIBDAP at low concentrations (1 µM, 5 µM, 10 µM) significantly reduced the apoptosis rate of PC12 cells (except at 20 µM); 5 µM TAT-HIBDAP had the most obvious effect. There were remarkable increases in ΔΨm at different concentrations (1 µM, 5 µM, 10 µM, 20 µM) of TAT-HIBDAP pretreatment, and 5 µM TAT-HIBDAP also had the most obvious effect. TAT-HIBDAP reversed the increased ratio of Bax/Bcl-2 and activation of Caspase-3 induced by OGD. CONCLUSION: TAT-HIBDAP is resistant to OGD-induced PC12 cell apoptosis by regulating the Bax/Bcl-2/Caspase-3 pathway, which may provide a novel therapeutic strategy for neonatal HIBD.


Assuntos
Fármacos Neuroprotetores , Oxigênio , Ratos , Animais , Oxigênio/metabolismo , Células PC12 , Glucose/metabolismo , Caspase 3/metabolismo , Proteína X Associada a bcl-2/metabolismo , Fármacos Neuroprotetores/farmacologia , Fluoresceína-5-Isotiocianato/farmacologia , Apoptose , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Encéfalo/metabolismo , Sobrevivência Celular
6.
Sci Total Environ ; 858(Pt 3): 159659, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36302416

RESUMO

Urban vegetation affects urban microclimate and maintains biodiversity, which is vital to the social-ecological system. However, there is a lack of research on quantitatively identifying urbanization stage impact on vegetation dynamics, and the stage difference in the response of vegetation dynamics to urbanization characteristics is not clear. In this study, taking Changsha City as an example, we explored the response of vegetation dynamics to urbanization, and identified the impact stages of urbanization on vegetation dynamics as well as their social-ecological characteristics. The results showed that the vegetation dynamics in Changsha City presented spatial pattern of "increase-decrease-increase" from downtown to outside in the past 20 years. The population density, GDP density and construction land proportion firstly inhibited vegetation growth, and then promoted it, with the turning points of 141.58 million yuan/km2, 1205 person/km2, and 19.80 %, respectively. Then, the urbanization impact on vegetation dynamics was quantitatively divided into three stages according to the vegetation change speed, and in different stages, urbanization impacts on vegetation dynamics were compared. This study illustrated the typical stage feature of the urbanization impact on vegetation dynamics.


Assuntos
Urbanização , Humanos , China
7.
Int Immunopharmacol ; 114: 109552, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36527882

RESUMO

OBJECTIVE: To investigate the effect of inactivated coronavirus disease 2019 (COVID-19) vaccination on frozen-thawed embryo transfer (FET) outcomes. METHODS: This retrospective cohort study enrolled 1,210 patients undergoing FET cycles in a single university-affiliated hospital between July 1, 2021, and May 1, 2022. Of them, 387 women with two full doses of inactivated SARS-CoV-2 vaccines (CoronaVac or BBIBP-CorV) after oocyte retrieval were assigned to the vaccinated group, while 823 were unvaccinated as controls. Propensity score matching and multiple regression analysis were applied to control for baseline and cycle characteristics (19 covariates in total). RESULTS: There were 265 patients in each group after matching. The rates of clinical pregnancy (58.5% vs. 60.8%; P = 0.595) and live birth (44.4% vs. 48.8%; P = 0.693) were similar between vaccinated and unvaccinated patients, with adjusted odds ratios of 0.89 (95% confidence interval [CI] 0.61-1.29) and 1.31 (95% CI 0.37-4.56), respectively. Consistently, no significant differences were found in serum human chorionic gonadotropin levels as well as biochemical pregnancy, biochemical pregnancy loss, and embryo implantation rates. Based on the time interval from vaccination to FET, vaccinated patients were further subdivided into two categories of ≤2 months and >2 months, and the outcomes remained comparable. CONCLUSION: Our study showed that inactivated COVID-19 vaccination in women did not have measurable detrimental impact on implantation performance and live birth outcome during FET treatment cycles. This finding denies the impairment of endometrial receptivity and trophoblast function by vaccine-induced antibodies at the clinical level.


Assuntos
COVID-19 , Complicações Infecciosas na Gravidez , Gravidez , Humanos , Feminino , Resultado da Gravidez , Vacinas contra COVID-19 , Taxa de Gravidez , Estudos Retrospectivos , COVID-19/prevenção & controle , SARS-CoV-2 , Transferência Embrionária , Criopreservação , Complicações Infecciosas na Gravidez/prevenção & controle
8.
Gastroenterol Res Pract ; 2022: 4498443, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36052377

RESUMO

Background: Liver transplantation (LT) is an effective treatment option for patients with end-stage liver disease; biliary complications are important cause of death in posttransplant patients. Endoscopic retrograde cholangiopancreatography (ERCP) has an irreplaceable role in the diagnosis and treatment of patients with biliary tract disease. Methods: The clinical data of patients with biliary strictures (BS) after LT treated with ERCP admitted to the Third Xiangya Hospital of Central South University from September 2016 to October 2021 were reviewed; the changes in temperature, bilirubin, and albumin before and after treatment and postoperative complications were analyzed. Results: A total of 41 patients were included in the study, and biliary stents were successfully placed in 37 cases (90.2%), while 4 cases (9.8%) were unsuccessful due to complete BS. Patients with ERCP guided biliary stenting had a significant improvement in bilirubin index compared to the preoperative period (P < 0.05). 27 patients (73.0%) had complete relief of symptoms after 1 ERCP-guided treatment, and 10 patients (27.0%) developed BS again at different times after the first ERCP treatment, among which 8 patients developed BS again within 1 year after the first treatment and 2 patients developed BS again after 1 year after the first treatment. The incidence of endoscopy-related adverse events was 35.14%, with no serious adverse events. Conclusion: ERCP-guided biliary stenting was an effective and safety treatment for BS after LT.

9.
Sci Total Environ ; 801: 149714, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34425438

RESUMO

The invasion of noxious weed species has long been associated with the degradation of alpine grasslands ecosystems. However, traditional in situ-based methods for surveying noxious weed species are generally time consuming and inefficient over large-scale areas. This paper investigates the possibility of applying multisource data to map the occurrence and spatial distribution of noxious weed species in degraded alpine grasslands in the Three-River Headwaters Region, China. Sentinel-2 image-related vegetation indices (VIs), field sample data and environmental variables were integrated to build a noxious weed species detection model based on the maximum entropy (MaxEnt) species modeling framework. The modeling results suggest that based on both training and testing AUC (area under the receiver operating characteristic (ROC) curve) values higher than 0.82, the VI-only variable model, the environmental-only variable model and the combined environmental and VI variables model, all yielded good simulation results. The spatial distributions of noxious weed species mapped by the VI-only variable model and the combined environmental and VI variable model were more concentrated, while the VI-only variable model yielded more scattered results. This analysis also explains why noxious weed species are mainly distributed in the low-elevation flat riverine zone in the study area. The model combining Sentinel-2 imagery-related VIs, environmental variables and in situ sample data proposed in this study can successfully map the occurrence and spatial distributions of noxious weed species. The method and results of this research can be used to help monitor noxious weed species invasions and better manage grassland ecosystems.


Assuntos
Ecossistema , Rios , China , Pradaria , Plantas Daninhas
10.
Front Public Health ; 9: 615817, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33816416

RESUMO

Background: More than 300 million smokers make China the largest cigarette consumer globally, which is a huge economic burden. Smoking cessation (SC) clinics can offer counseling and follow-up services. The operational experience of SC clinics in China needs to be summarized and improved based on research evidence. Purpose: The objectives of this study were to describe quit rates among attendees of SC clinics in Hunan and assess predictors of successful SC. Methods: The participants in this study were smokers who visited the SC clinic of Hunan Cancer Hospital from February 1, 2015 to September 30, 2018. Individuals who received individual counseling and assessment from the SC clinic staff and were willing to quit smoking were eligible for inclusion. Those with critical illness or cancer were excluded. Application of smoking cessation clinic registration form (unified by Chinese Center for Disease Control and Prevention) was used to assess participants at the consultation. Follow-ups and counseling were performed over telephone at 1 week, 1 month, and 3 months after the initial cessation consultation or in times of need. Successful SC was checked for at 3 months after the start of SC. Results: A total of 328 smokers (mean age 45.67 ± 12.38 years) had participated. The abstinence rate at 3 months was 28.4%. Binary regression analysis revealed significant independent predictors to be the total numbers of SC follow up sessions, previous SC attempts, and participants' decision on when to quit smoking (The relative to quit immediately group, quit within 30 days, quit after 30 days, and undecided quit were less likely to succeed in quitting. while quit within seven days had no statistical significance. Conclusion: SC clinics can achieve a desirably high quit rate. Participant's previous attempts at quitting, three or more follow-ups, and the decision to quit immediately or within seven days were factors helpful in predicting the success of SC.


Assuntos
Abandono do Hábito de Fumar , Adulto , China/epidemiologia , Aconselhamento , Humanos , Pessoa de Meia-Idade , Fumantes , Fumar
11.
Subst Use Misuse ; 55(9): 1501-1508, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32569534

RESUMO

Background: The high prevalence of betel quid chewing is associated with a serious burden of oral diseases. However, there is limitertd research on the effects of betel quid, smoking, and alcohol on oral cancer in the Hunan province, China. Objectives: We investigated the relationship between oral cancer and betel quid chewing, smoking, and alcohol consumption in the betel quid endemic area of Hunan province. Methods: A paired case-control study from January 2014 to September 2015 was conducted in the Hunan province, China. We recruited 304 oral cancer patients and 304 controls as subjects, and both groups were treated in the same provincial cancer hospital. Control subjects and cancer patients were matched by sex, age (3-year groups), education level, and residential district. Conditional logistic regression analyses were used to examine the associations between oral cancer and betel quid, smoking, and alcohol consumption. Results: A significantly increased risk of oral cancer was associated with smoking, alcohol consumption, and betel quid chewing (odds ratio [OR] of 1.49, 1.56, and 5.80, respectively; p < .05). The risk of cancer was significantly elevated at high levels of intake and prolonged duration of consumption of betel quid, smoking, and alcohol. After adjusting for confounders, betel quid chewers were found to have almost 5 times increased risk for oral cancer (OR = 5.41, 95% confidence interval: 3.32-8.80, p < .001). Conclusions: There was a positive correlation between betel quid chewing and risk of oral cancer in the Hunan Province.


Assuntos
Areca , Neoplasias Bucais , Consumo de Bebidas Alcoólicas/epidemiologia , Areca/efeitos adversos , Estudos de Casos e Controles , China/epidemiologia , Humanos , Neoplasias Bucais/epidemiologia , Neoplasias Bucais/etiologia , Fatores de Risco , Fumar
12.
Sci Total Environ ; 660: 765-775, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30743962

RESUMO

Multifunctional landscape has become a new discipline growth point in landscape ecology. Globally mountainous areas occupy about one fifth of Earth's surface. However, few studies focused on landscape multifunctionality in mountainous areas. Taking Dali Bai Autonomous Prefecture, China, as a case study area, five typical landscape functions (net primary productivity, soil retention, water yield, crop production, and residential support) were quantified and mapped. Hotspots of multiple landscape functions were identified using spatial overlap tools, interaction between each landscape function pair was discussed through Spearman's rank correlation analysis, and development zoning was conducted based on landscape function bundle. The results showed that, about 61% of the study area had at least one kind of landscape function hotspot, with only 2.7% covering three or more kinds of landscape function hotspots. Significant trade-offs or synergies existed between all pairs of landscape functions, except the pair of net primary productivity and residential support. With the application of Self-Organizing Feature Maps (SOFM) method, the study area was divided into four types of development zones (i.e. ecological shelter area, ecological transition area, suburban development area, and urban agglomeration area) which were all corresponding to different landscape function bundles. This study could provide spatial guidance for differentiated sustainable developing in mountainous areas according to local conditions of landscape multifunctionality.

13.
Sci Total Environ ; 644: 781-790, 2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-29990926

RESUMO

The rapid process of urbanization, accompanied by the sharp increase of urban population and expansion of artificial surface, has resulted in the loss of natural ecosystems and the degradation of ecosystem services. Identifying and protecting key places that have high importance for ecological sustainability are great challenges. Ecological security patterns are such an integrated approach to protecting regional ecological sustainability. In this study, taking Yunnan Province, China as a case study area, ecological sources were identified through ecosystem services, and circuit theory was used to model ecosystem processes in heterogeneous landscapes via calculating the 'resistance' or 'current', and thus to identify ecological corridors and key ecological nodes. The results showed that, ecological security patterns included 66 ecological sources, 186 ecological corridors, 24 pinch-points and 10 barriers. In details, the ecological sources were mainly distributed in the southwest and northwest of Yunnan Province, with the ecological corridors locating along the high mountains, and both ecological sources and corridors were mostly covered with forest land. Pinch-points covered by forest land and cultivated land, were distributed in the middle of Yunnan Province along the rivers. Approximately 75.9% nature reserves were located in the identified ecological sources, and the remainings were mainly distributed in eastern Yunnan Province with small area, showing the effectiveness in identifying ecological security patterns. Among 81 projects of low-slope hill development carried out in Yunnan Province, 46.9% showed potential human stress on regional ecological security. Based on ecosystem services and circuit theory, this study provides a new approach to identifying the spatial range of ecological corridors and the specific location of key nodes for effective ecological conservation and restoration.

14.
Sci Total Environ ; 635: 487-497, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29677674

RESUMO

As an important theme in global climate change and urban sustainable development, the changes of land surface temperature (LST) and surface urban heat island (SUHI) have been more and more focused by urban ecologists. This study used land-use data to identify the urban-rural areas in 285 cities in China and comparatively analyzed LST in urban-rural areas with the perspective of spatial-temporal dynamics heterogeneity. The results showed that, 98.9% of the cities exhibited SUHI effect in summer nighttime and the effect was stronger in northern cities than that in southern cities. In 2010, the mean SUHI intensity was the largest in summer daytime, with 4.6% of the cities having extreme SUHI of over 4°C. From 2001 to 2010, the nighttime LST of most cities increased more quickly in urban areas compared with rural areas, with an increasing tendency of the urban-rural LST difference. The difference in the urban- rural LST change rate was concentrated in the range of 0-0.1°C/year for 68.0% of cities in winter and 70.8% of cities in summer. For the higher LST increasing in urban areas compared with rural areas, there were more cities in summer than winter, indicating that the summer nighttime was the key temporal period for SUHI management. Based on the change slope of urban-rural LST, cities were clustered into four types and the vital and major zones for urban thermal environment management were identified in China. The vital zone included cities in Hunan, Hubei and other central rising provinces as well as the Beibu Gulf of Guangxi Province. The major zone included most of the cities in Central Plain Urban Agglomeration, Yangtze River Delta and Pearl River Delta. These results can provide scientific basis for SUHI adaptation in China.

15.
Sci Total Environ ; 625: 849-860, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29306828

RESUMO

Ecosystem services are the benefits people obtain from ecosystems, and ecosystem services trade-offs have been widely applied to the development of land-use policy. Although previous studies have focused on trade-offs of ecosystem services, a scenario approach has been seldom used. The scenario approach can reveal the changes of ecosystem services for different land-use patterns in the future, and is of great significance for land-use decisions and ecosystem management. Based on the actual situation of deteriorating water quality and dwindling water supply in the Erhai Lake Basin of southwest China, this study put forward to convert paddy land to dry land (PLDL) in the basin, and simulated its potential impact on ecosystem services. Taking environmental pollution, social impact, economic benefit and residential participation into consideration, four scenarios of PLDL were designed. Then, four ecosystem services (water purification, water yield, soil conservation and rice production) were calculated for each scenario. The optimal scenario of PLDL in the Erhai Lake Basin was identified by trade-offs of the four ecosystem services. The results showed that the total nitrogen export could be reduced by 42.07% and water yield can be increased by 5.61% after converting 100% of paddy lands to dry land, thereby greatly improving the water quality and increasing the water yield of Erhai Lake. However, PLDL involving 100% of paddy lands also increased the sediment export by 17.22%, and eliminated rice production in the region. By comparing the four PLDL scenarios for converting just 50% of paddy lands, the residential participation scenario was identified to be the best choice for PLDL implementation because it achieved the best level of water purification and had the smallest negative effect on other ecosystem services. The optimal scenario for each township showed spatial differentiation, and there were conflicts between the optimal scenarios at basin scale and township scale, suggesting that the object and the spatial-temporal scale should be taken into consideration in land-use decisions using ecosystem services trade-offs.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Oryza/crescimento & desenvolvimento , Qualidade da Água , China , Produtos Agrícolas/crescimento & desenvolvimento , Sedimentos Geológicos , Lagos
16.
Sci Total Environ ; 607-608: 706-714, 2017 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-28711000

RESUMO

Ecosystem service is the key comprehensive indicator for measuring the ecological effects of urbanization. Although various studies have found a causal relationship between urbanization and ecosystem services degradation, the linear or non-linear characteristics are still unclear, especially identifying the impact thresholds in this relationship. This study quantified four ecosystem services (i.e. soil conservation, carbon sequestration and oxygen production, water yield, and food production) and total ecosystem services (TES), and then identified multiple advantageous area of ecosystem services in the peri-urban area of Beijing City. Using piecewise linear regression, the response of TES to urbanization (i.e., population density, GDP density, and construction land proportion) and its thresholds were detected. The results showed that, the TES was high in the north and west and low in the southeast, and there were seven multiple advantageous areas (distributed in the new urban development zone and ecological conservation zone), one single advantageous area (distributed in the ecological conservation zone), and six disadvantageous areas (mainly distributed in the urban function extended zone). TES response to population and economic urbanization each had a threshold (229personkm-2 and 107.15millionyuankm-2, respectively), above which TES decreased rapidly with intensifying urbanization. However, there was a negative linear relationship between land urbanization and TES, which indicated that the impact of land urbanization on ecosystem services was more direct and effective than that of population and economic urbanization. It was also found that the negative impact of urbanization on TES was highest in the urban function extended zone, followed in descending order by that in the new urban development zone and ecological conservation zone. According to the detected relationships between urbanization and TES, the economic and population urbanization should be strengthened accompanied by slowing or even reducing land urbanization, so as to achieve urban ecological sustainability with less ecosystem services degradation.


Assuntos
Conservação dos Recursos Naturais , Urbanização , Agricultura , Pequim , Sequestro de Carbono , Cidades , Ecossistema , Oxigênio , Solo , Recursos Hídricos
17.
Environ Monit Assess ; 187(11): 722, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26514805

RESUMO

Quantifying the long-term trends of changes in terrestrial vegetation on a large scale is an effective method for detecting the effects of global environmental change. In view of the trend towards overall restoration and local degradation of terrestrial vegetation in China, it is necessary to pay attention to the spatial processes of vegetative restoration or degradation, as well as to clarify the temporal and spatial characteristics of vegetative growth in greater geographical detail. However, traditional linear regression analysis has some drawbacks when describing ecological processes. Combining nonparametric linear regression analysis with high-order nonlinear fitting, the temporal and spatial characteristics of terrestrial vegetative growth in China during 1982-2012 were detected using the third generation of Global Inventory Modeling and Mapping Studies (GIMMS3g) dataset. The results showed that high-order curves could be effective. The region joining Ordos City and Shaanxi Gansu Ningxia on the Loess Plateau may have experienced restoration-degradation-restoration processes of vegetative growth. In the Daloushan Mountains, degradation-restoration processes of vegetative growth may have occurred, and the occurrence of several hidden vegetative growth processes was located in different regions of eastern China. Changes in cultivated vegetation were inconsistent with changes in other vegetation types. In southern China and some high-altitude areas, temperature was the primary driver of vegetative growth on an interannual scale, while in the north, the effect of rainfall was more significant. Nevertheless, the influence of climate on vegetation activity in large urban areas was weak. The trend types of degradation-restoration processes in several regions were inconsistent with the implements of regional land development and protection strategy. Thus, the role of human activity cannot be ignored. In future studies, it will be still necessary to quantify the effects of human management on spatial patterns, develop trend-fitting methods, and explore more refined methods of analyzing the driving forces affecting large-scale changes in vegetative growth.


Assuntos
Monitoramento Ambiental/métodos , Plantas/classificação , China , Clima , Ecologia , Geografia , Humanos , Temperatura
18.
Environ Manage ; 53(3): 636-47, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24318403

RESUMO

A comparison of different transportation route types and their combined effects on landscape diversity was conducted within Tiaoxi watershed (China) between 1994 and 2005. Buffer analysis and Mann-Kendall's test were used to quantify the relationships between distance from transportation routes (railway, highway, national, and provincial road) and a family of landscape diversity parameters (Simpson's diversity index, Simpson's evenness index, Shannon's diversity index, and Shannon's evenness index). One-way ANOVA was further applied to compare influences from different route types and their combined effects. Five other landscape metrics (patch density, edge density, area-weighted mean shape index, connectance index, and Euclidean nearest neighbor distance) were also calculated to analyze the associations between landscape diversity and landscape pattern characteristics. Results showed that transportation routes exerted significant impacts on landscape diversity. Impact from railway was comparable to that from highway and national road but was more significant than that from provincial road. The spatial influential range of railway and national road was wider than that of highway and provincial road. Combined effects of routes were nonlinear, and impacts from different route types were more complex than those from the same type. The four landscape diversity metrics were comparably effective at the buffer zone scale. In addition, landscape diversity can be alternatively used to indicate fragmentation, connectivity, and isolation at route buffer scale. This study demonstrates an applicable approach to quantitatively characterize the impacts from transportation routes on landscape patterns and has potential to facilitate route network planning.


Assuntos
Biodiversidade , Ecossistema , Meios de Transporte/métodos , Urbanização , Análise de Variância , China , Monitoramento Ambiental/métodos , Humanos , Densidade Demográfica
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